Molecular characterization of Brazilian FeLV strains in São Luis, Maranhão Brazil.

The feline leukemia virus (FeLV) belongs to the Retroviridae family and Gammaretrovirus genus, and causes a variety of neoplastic and non-neoplastic diseases in domestic cats (Felis catus), such as thymic and multicentric lymphomas, myelodysplastic syndromes, acute myeloid leukemia, aplastic anemia, and immunodeficiency. The aim of the present study was to carry out the molecular characterization of FeLV-positive samples and determine the circulating viral subtype in the city of São Luís, Maranhão, Brazil, as well as identify its phylogenetic relationship and genetic diversity. The FIV Ac/FeLV Ag Test Kit (Alere™) and the commercial immunoenzymatic assay kit (Alere™) were used to detect the positive samples, which were subsequently confirmed by ELISA (ELISA - SNAP® Combo FeLV/FIV). To confirm the presence of proviral DNA, a polymerase chain reaction (PCR) was performed to amplify the target fragments of 450, 235, and 166 bp of the FeLV gag gene. For the detection of FeLV subtypes, nested PCR was performed for FeLV-A, B, and C, with amplification of 2350-, 1072-, 866-, and 1755-bp fragments for the FeLV env gene. The results obtained by nested PCR showed that the four positive samples amplified the A and B subtypes. The C subtype was not amplified. There was an AB combination but no ABC combination. Phylogenetic analysis revealed similarities (78% bootstrap) between the subtype circulating in Brazil and FeLV-AB and with the subtypes of Eastern Asia (Japan) and Southeast Asia (Malaysia), demonstrating that this subtype possesses high genetic variability and a differentiated genotype.

Diagnosis and phylogenetic analysis of bovine leukemia virus in dairy cattle in northeastern Brazil.

Enzootic bovine leukosis (EBL) is a chronic viral disease of wide distribution in cattle herds and may take several years for the first manifestation of clinical signs. Most animals do not present clinical signs. However, the economic losses are underestimated due to this disease. Thus, this work aimed to detect and characterize BLV in dairy cattle in the Maranhão state, northeastern Brazil. Blood samples were collected from 176 animals from 8 municipalities in the southeastern state of Maranhão. Bovine blood samples were subjected to DNA extraction and molecular diagnosis using nested PCR assays for BLV, targeting gp51 gene. Positive samples were then sequenced and then subjected to phylogenetic inferences. BLV DNA was detected in 16 cattle (16/176, 9.09%) in 4 municipalities. Phylogenetic analyzes showed that the sequence obtained clustered in a clade containing BLV sequences classified as genotype 6, with a high degree of support. Our data shows BLV occurrence in the Northeast of Brazil and the identification of genotype 6 in this region. These findings contribute to the molecular epidemiology of this agent in Brazil.

High genetic diversity of Anaplasma marginale infecting dairy cattle in northeastern Brazil.

Anaplasma marginale is an obligate intracellular Gram-negative bacterium found in ruminants' erythrocytes and is the etiological agent of bovine anaplasmosis. The bacterium's genetic diversity has been characterized based on sequences of major surface proteins (MSPs), such as MSP1α. The aim of the present study was to investigate the genetic diversity of A. marginale in cattle in the state of Maranhão, northeastern Brazil. To this end, 343 blood samples were harvested and subjected to iELISA assays using the recombinant surface protein MSP5. Out of 343 blood samples, 235 (68.5%) were randomly chosen and submitted to DNA extraction, qPCR and conventional PCR targeting the msp1α gene to determine amino acid sequences and classify the genotypes. The iELISA results showed 81.34% seropositivity (279/343), whereas qPCR revealed 224 positive samples (95.32%). Among these qPCR-positive samples, 67.4% (151/224) were also positive in the cPCR. Among the 50 obtained sequences, 21 strains had not been previously reported. Regarding the genotypes, H (26/50) and E (18/50) were identified most often, while genotypes F and C were only identified twice each and B and G once each. In conclusion, high prevalence and genetic diversity for A. marginale were observed in dairy cattle herds in the state of Maranhão.

Anti-Ehrlichia properties of the dichloromethane fraction of Ageratum conyzoides associated with doxycycline: In vitro study / Propriedades anti-Ehrlichia da fração diclorometânica de Ageratum conyzoides associada com doxiciclina: estudo in vitro

ABSTRACT: The increasing number of cases of canine ehrlichiosis caused by Ehrlichia canis in hospitals and veterinary clinics has demonstrated the need for a new drug protocol for this disease. Doxycycline is used to treat ehrlichiosis, but the resistance of the microorganism to this treatment protocol, as well as the various side effects to the animals, has become a concern. Several studies have shown a positive interaction with extracts of plants and drugs, which allow for the reduction of the concentration necessary to produce the desired effect, minimizing adverse effects. This study determined the efficiency of the combination of the dichloromethane (DCM) fraction of Ageratum conyzoides L. with anti-Ehrlichia activity and doxycycline by using the checkerboard assay. Plant material was collected in São Luís, northeastern Brazil, followed by extraction in MeOH: H2O (8:2) and partitioning of the DCM fraction. After determining the Minimum Inhibitory Concentration (MIC) of the fraction under study against DH82 cells infected with Ehrlichia canis, it was combined with doxycycline to derive the Fractional Inhibitory Concentration Index (CIF Index). A reduction of 5.83 times the doxycycline minimum inhibitory concentration was observed, showing that this fraction of A. conyzoides composed predominantly by the class of lignans, identified by mass spectrometry notably intensified the activity of doxycycline against E. canis, resulting in a synergistic effect.

RESUMO: O crescente número de casos de erliquiose canina por Ehrlichia canis em hospitais e clínicas veterinárias tem demonstrado a necessidade de um novo protocolo de medicamentos para essa doença. A doxiciclina é usada para tratar a erliquiose, mas a resistência do microrganismo a esse protocolo de tratamento, bem como os diversos efeitos colaterais para os animais, tornou-se uma preocupação. Vários estudos têm demonstrado interação positiva com extratos de plantas e fármacos, que permitem a redução da concentração necessária para produzir o efeito desejado, minimizando os efeitos adversos. Este estudo determinou a eficiência da combinação da fração diclorometânica (DCM) de Ageratum conyzoides L. com atividade anti-Ehrlichia canis associada com doxiciclina por meio do ensaio de Checkerboard. O material vegetal foi coletado em São Luís, Maranhão, nordeste do Brasil, seguido pela extração em MeOH:H2O (8:2) e partição da fração diclorometânica. Após a determinação da Concentração Inibitória Mínima (CIM) da fração em estudo frente às células DH82 infectadas com Ehrlichia canis, a mesma foi combinada com a doxiciclina para derivação do Índice de Concentração Inibitória da Fração (Índice CIF). Observou-se uma redução de 5,83 vezes a concentração inibitória mínima da doxiciclina mostrando que esta fração de A. conyzoides, composta predominantemente por lignanas identificadas por espectrometria de massas, notavelmente intensificou a atividade desse fármaco contra E. canis, resultando em um efeito sinérgico.

High genetic diversity of Anaplasma marginale infecting dairy cattle in northeastern Brazil / Alta diversidade genética de Anaplasma marginale em bovinos de leite no nordeste do Brasil

Abstract Anaplasma marginale is an obligate intracellular Gram-negative bacterium found in ruminants' erythrocytes and is the etiological agent of bovine anaplasmosis. The bacterium's genetic diversity has been characterized based on sequences of major surface proteins (MSPs), such as MSP1α. The aim of the present study was to investigate the genetic diversity of A. marginale in cattle in the state of Maranhão, northeastern Brazil. To this end, 343 blood samples were harvested and subjected to iELISA assays using the recombinant surface protein MSP5. Out of 343 blood samples, 235 (68.5%) were randomly chosen and submitted to DNA extraction, qPCR and conventional PCR targeting the msp1α gene to determine amino acid sequences and classify the genotypes. The iELISA results showed 81.34% seropositivity (279/343), whereas qPCR revealed 224 positive samples (95.32%). Among these qPCR-positive samples, 67.4% (151/224) were also positive in the cPCR. Among the 50 obtained sequences, 21 strains had not been previously reported. Regarding the genotypes, H (26/50) and E (18/50) were identified most often, while genotypes F and C were only identified twice each and B and G once each. In conclusion, high prevalence and genetic diversity for A. marginale were observed in dairy cattle herds in the state of Maranhão.

Resumo Anaplasma marginale é uma bactéria Gram-negativa intracelular obrigatória de eritrócitos de ruminantes e responsável pela anaplasmose bovina. A diversidade genética de A. marginale tem sido caracterizada com base nas sequências das principais proteínas de superfície (MSPs), como a MSP1α. O objetivo deste estudo foi investigar a diversidade genética de A. marginale em bovinos no estado do Maranhão, Nordeste do Brasil. Dessa forma, 343 amostras de sangue foram submetidas ao ensaio iELISA, utilizando-se a proteína recombinante MSP5. Das 343 amostras de sangue, 235 (68,5%) foram escolhidas aleatoriamente e submetidas à extração de DNA, qPCR e PCR convencional para gene msp1α, para determinação das sequências de aminoácidos e classificação dos genótipos. Os resultados do iELISA mostraram 81,34% de soropositividade (279/343), enquanto qPCR revelou 224 amostras positivas (95,32%). Dentre estas na qPCR, 67,4% (151/224) mostraram-se positivas no PCR convencional. Das 50 sequências obtidas, 21 cepas não haviam sido relatadas anteriormente. Em relação aos genótipos, H (26/50) e E (18/50) foram os mais frequentes, enquanto os genótipos F e C foram identificados apenas duas vezes cada, e B e G uma vez cada. Em conclusão, alta prevalência e marcante diversidade genética de A. marginale foram observadas em rebanhos leiteiros no estado do Maranhão.

Occurrence of Bartonella genotypes in bats and associated Streblidae flies from Maranhão state, northeastern Brazil.

Bartonella is a genus of emerging zoonotic bacteria that are mainly associated with mammalian erythrocytes and endothelial cells. Bats are natural reservoirs for a variety of important pathogens that impact human and animal health. Recent reports have highlighted the role of bats and bat flies in the maintenance of Bartonella. Here, we showed that none of the 29 bat DNA blood samples obtained from five bat species in São Luís Island, state of Maranhão, northeastern Brazil, were positive for Bartonella in qPCR assays targeting nuoG. On the other hand, three out of 15 DNA samples (20%) from flies in the family Streblidae were positive for Bartonella. The BLASTn results showed that the gltA and rpoB sequences shared identities ranging from 97.2% to 100%, with Bartonella sequences amplified from bats or bat flies from Costa Rica and Brazil. These findings were supported by phylogenetic analyses based on Bayesian inferences. The present study showed that Bartonella genotypes are present in bat flies, thus shedding some light on the distribution of bat fly-related Bartonella genotypes in South America.

Occurrence of Bartonella genotypes in bats and associated Streblidae flies from Maranhão state, northeastern Brazil / Ocorrência de genótipos de Bartonella em morcegos e moscas Streblidae no Estado do Maranhão, Nordeste do Brasil

Abstract Bartonella is a genus of emerging zoonotic bacteria that are mainly associated with mammalian erythrocytes and endothelial cells. Bats are natural reservoirs for a variety of important pathogens that impact human and animal health. Recent reports have highlighted the role of bats and bat flies in the maintenance of Bartonella. Here, we showed that none of the 29 bat DNA blood samples obtained from five bat species in São Luís Island, state of Maranhão, northeastern Brazil, were positive for Bartonella in qPCR assays targeting nuoG. On the other hand, three out of 15 DNA samples (20%) from flies in the family Streblidae were positive for Bartonella. The BLASTn results showed that the gltA and rpoB sequences shared identities ranging from 97.2% to 100%, with Bartonella sequences amplified from bats or bat flies from Costa Rica and Brazil. These findings were supported by phylogenetic analyses based on Bayesian inferences. The present study showed that Bartonella genotypes are present in bat flies, thus shedding some light on the distribution of bat fly-related Bartonella genotypes in South America.

Resumo Bartonella é um gênero de bactérias zoonóticas emergentes associadas principalmente a eritrócitos e células endoteliais de mamíferos. Morcegos são reservatórios naturais para uma variedade de patógenos importantes que afetam a saúde humana e animal. Além disso, estudos recentes destacaram o papel dos morcegos e de moscas associadas a morcegos na manutenção de Bartonella. No presente estudo, nenhuma das 29 amostras de DNA obtidas a partir do sangue de cinco espécies de morcegos amostrados na ilha de São Luís, estado do Maranhão, Nordeste do Brasil, foi positiva para Bartonella nos ensaios de qPCR direcionados ao gene nuoG. Por outro lado, três das 15 (20%) amostras de DNA de moscas da família Streblidae foram positivas para Bartonella. Os resultados do BLASTn mostraram que as sequências dos genes gltA e rpoB compartilharam identidade, variando de 97,2% a 100%, com as sequências de Bartonella amplificadas em morcegos ou moscas amostrados na Costa Rica ou Brasil. Tais resultados corroboraram as análises filogenéticas realizadas por Inferência Bayesiana. O presente estudo mostrou a ocorrência de Bartonella em moscas de morcegos, auxiliando a esclarecer a distribuição dos genótipos de Bartonella relacionadas a moscas Streblidae na América do Sul.

Anti-Ehrlichia properties of the essential oil of Ageratum conyzoides L. and its interaction with doxycycline.

Canine Monocytic Ehrlichiosis (CME) is an infectious disease caused by the rickettsia organism Ehrlichia canis which is transmitted mainly the ixodid brown dog tick Rhipicephalus sanguineus. The prevalence of E. canis infection has been increasing in recent years. The World Health Organization has been warned about antibiotics resistance and one of the way to prevent this situation is found new compound with this property. Doxycycline is the treatment of choice for this tick-borne disease. Adverse effects are noted in dogs that are sensitive to this drug. Antibiotic resistance may also occur. The present study aimed to evaluate the anti-Ehrlichia properties of the essential oil of the aerial parts of Ageratum conyzoides L. in infected DH82 cells, as well as its anti-Ehrlichia activity associated with doxycycline using the checkerboard assay. A. conyzoides is a native plant from northeast Brazil with many reports of ethnopharmacological applications. The essential oil of A. conyzoides was extracted from the aerial parts of the plant using the hydrodistillation method. E. canis-infected DH82 cells were cultured in DMEM (Dulbecco's Modified Eagle Medium), maintained at 37 °C and 5% CO2, and standardized at a 70% infection rate for the initiation of treatment protocols. The tests were first carried out with the aim of defining the IC50. The combined effect of doxycycline and A. conyzoides essential oil was then determined using the checkerboard dilution technique (checkerboard method) in which the IC50 was 200 µg/mL. The doxycycline reduction index from the combined effect was 4.90 times resulting in a synergistic effect. To the authors' knowledge, this is the first alternative treatment (alternative therapy) based on bioactive molecules that have antibacterial activity against E. canis.

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil / Detecção molecular de Mycoplasma suis em suínos de criações extensivas no estado do Maranhão, nordeste do Brasil

Abstract Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.

Resumo Mycoplasma suis é uma bactéria que causa a hemoplasmose em suínos. Este agente é capaz de se aderir à superfície dos eritrócitos de suínos, ocasionando deformações estruturais nestas células. No Brasil, poucos são os relatos acerca do parasita, da infecção e de seus impactos econômicos nas esferas produtiva e sanitária. O objetivo deste estudo foi investigar, por meio da PCR em tempo real quantitativa (qPCR) baseada no gene 16S rRNA, a ocorrência de M. suis em 64 amostras de sangue de suínos de criações extensivas dos municípios de Itapecuru Mirim, Santa Rita e Rosário, localizados no estado do Maranhão. Foram obtidos um percentual de 82,3%, 65,2% e 25% de amostras positivas na qPCR para M. suis nos municípios de Itapecuru Mirim, Santa Rita e Rosário, respectivamente. Este estudo mostra que M. suis circula entre os suínos de criações extensivas no estado do Maranhão.

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil.

Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.

Molecular detection of Mycoplasma suis in extensive pig production systems in the State of Maranhão, northeast Brazil / Detecção molecular de Mycoplasma suis em suínos de criações extensivas no estado do Maranhão, nordeste do Brasil

Mycoplasma suis is a bacterium that causes hemoplasmosis in pigs. This agent is capable of adhering to the surface of porcine erythrocytes, inducing structural changes on these cells. In Brazil, there are few reports about the disease, its causal agent, and the economic impact of this pathogen on pig production systems and farm sanitation. The present study aimed to investigate the occurrence of M. suis in extensive swine farms located in the counties of Itapecuru Mirim, Santa Rita and Rosario, State of Maranhão, northeast Brazil. For such purpose, 64 blood samples of pigs from these facilities were tested for M. suis using a 16S rRNA gene-based quantitative real-time PCR (qPCR); 82.3%, 65.2% and 25% of blood samples of swine from farms in the cities of Itapecuru Mirim, Santa Rita and Rosario were positive for M. suis by qPCR, respectively. This study shows, for the first time, that M. suis circulates in pig populations from the state of Maranhão, Northeast Brazil.

Mycoplasma suis é uma bactéria que causa a hemoplasmose em suínos. Este agente é capaz de se aderir à superfície dos eritrócitos de suínos, ocasionando deformações estruturais nestas células. No Brasil, poucos são os relatos acerca do parasita, da infecção e de seus impactos econômicos nas esferas produtiva e sanitária. O objetivo deste estudo foi investigar, por meio da PCR em tempo real quantitativa (qPCR) baseada no gene 16S rRNA, a ocorrência de M. suis em 64 amostras de sangue de suínos de criações extensivas dos municípios de Itapecuru Mirim, Santa Rita e Rosário, localizados no estado do Maranhão. Foram obtidos um percentual de 82,3%, 65,2% e 25% de amostras positivas na qPCR para M. suis nos municípios de Itapecuru Mirim, Santa Rita e Rosário, respectivamente. Este estudo mostra que M. suis circula entre os suínos de criações extensivas no estado do Maranhão.

Hepatic extracellular matrix alterations in dogs naturally infected with Leishmania (Leishmania) chagasi.

Summary The aim of this work was to study alterations in the extracellular matrix of liver in dogs naturally infected with Leishmania (Leishmania) chagasi that are correlated with clinical aspects and with histological, parasitological and immunological findings. The study was carried out on 30 dogs, 10 uninfected (control group) and 20 infected. The infected animals were further divided into two groups: an asymptomatic group of 10 dogs without clinical signs of the disease; and a symptomatic group of 10 dogs with classical clinical signs. All thirty animals were mongrel dogs of undefined age, obtained from the municipality of Belo Horizonte, MG, metropolitan area. During necropsy, liver fragments were collected and fixed in 10% buffered formaldehyde for histological examination. Paraffined sections of the tissues were stained with haematoxylin-eosin, Gomori's ammoniacal silver stain for reticular fibres and strepto-avidin peroxidase for immunohistochemical detection of Leishmania amastigotes. Frozen tissue sections were stained by immunofluorescence for fibronectin (FN) and laminin (LN). Liver collagen deposition was significantly greater in the infected than the control animals and differed significantly between the symptomatic and asymptomatic dogs. There was a positive correlation between the parasite load and liver collagen deposition. The increased collagen deposition in infected animal livers may be associated with the parasite burden. Adhesive FN and LN fibres were significantly more highly expressed in the livers of symptomatic than of asymptomatic dogs. Our results demonstrate that canine visceral leishmaniasis causes fibrogenesis in liver, associated with the parasite load and degenerative processes.