4-hydroxy-2-nonenal as a marker of the oxidative stress in brains of dogs with canine distemper / 4-hidroxi-2-nonenal como marcador de estresse oxidativo no cérebro de cães com cinomose

Canine Distemper is a disease caused by Canine morbillivirus (CM), a pantropic virus that can affect the central nervous system (CNS), causing demyelination. However, the pathogenesis of this lesion remains to be clarified. Brain samples of 14 naturally infected dogs by CM were analyzed to evaluate the presence of oxidative stress and demyelination. RT-PCR assay was performed to confirm a diagnosis of canine distemper in the brain, immunohistochemistry anti-CM was used to localize the viral proteins in the tissue, and anti-4-hydroxy-2-nonenal (4-HNE) was a marker of a product of lipid peroxidation. The results showed the presence of viral proteins in the demyelinated area with the presence of 4-HNE. Our results suggest that the CM virus infection causes oxidative stress leading to lipid peroxidation, which causes tissue damage and demyelination. In conclusion, oxidative stress plays a significant role in canine distemper pathogenesis in the CNS.(AU)

A cinomose canina é uma doença causada pelo Morbilivírus canino (CM), um vírus pantrópico que pode afetar o sistema nervoso central (SNC), causando desmielinização. No entanto, a patogênese dessa lesão não está totalmente esclarecida. RT-PCR e imuno-histoquímica foram realizadas para confirmação do diagnóstico de cinomose em amostras de encéfalo de 14 cães naturalmente infectados. Após confirmação, foi realizada uma avaliação do estresse oxidativo por imuno-histoquímica com uso de anti-4-hidroxi-nonenal (4HNE) como marcador de produtos resultantes da peroxidação lipídica. Os resultados sugerem que a infecção pelo CM causa estresse oxidativo no tecido, levando a peroxidação lipídica, a qual causa danos ao tecido, culminando com desmielinização. Conclui-se que o estresse oxidativo tem papel importante na patogênese da cinomose canina no sistema nervoso central.(AU)

Schmallenberg virus: research on viral circulation in Brazil.

Schmallenberg virus (SBV-Orthobunyavirus serogroup Simbu) is an emerging RNA vector-borne virus which has an important impact in animal health within Europe, and some Asian and African countries. It is mainly reported in ruminants, causing congenital malformations and stillbirths. However, there are no studies regarding the occurrence, diagnosis, or surveillance of SBV in Brazil, due to the lack of diagnostic techniques available so far. This study aimed to implement a reliable diagnostic technique able to detect the SBV in Brazil and also to investigate occurrence of the virus in this country. A molecular technique, quantitative reverse transcription polymerase chain reaction (RT-qPCR), was used to analyze 1665 bovine blood samples and 313 aborted fetuses, as well as 596 serum samples were analyzed by serological analysis. None of the blood and fetus samples analyzed was positive for SBV, and neither serum samples were reactive for antibodies anti-SBV. Thus, although Brazil presents suitable conditions for the dissemination of the SBV, results of the present study suggest that SBV did not propagate in the analyzed bovine population.

A novel real-time PCR to detect Cetacean morbillivirus in Atlantic cetaceans.

Cetacean morbillivirus (CeMV, family Paramyxoviridae) is a re-emergent pathogen associated with severe epizootic outbreaks causing high mortality among cetaceans worldwide. Recently, CeMV caused an unusual mortality event of Guiana dolphins (Sotalia guianensis) in Brazil. Partial sequence of the viral phosphoprotein (P) gene showed that the Guiana dolphin morbillivirus (GDMV) might represent a new lineage of CeMV. This study aimed to develop a molecular technique to detect the most common CeMV strains known to circulate in the Atlantic Ocean: GDMV, Dolphin morbillivirus (DMV) and Pilot-whale morbillivirus (PWMV). A sensible real-time reverse transcription polymerase chain reaction (RT-qPCR) method based on intercalating dye, targeting the P gene was described. This assay successfully detected GDMV, PWMV and DMV from field samples. Its performance was compared to a RT-qPCR method that specifically detects GDMV. Both assays had high sensibility and excellent intra- and inter-assay reproducibility. A total of 109 field samples from 32 Guiana dolphins were screened for CeMV by conventional RT-PCR in parallel with the RT-qPCR assay. The detection rate increased from 32% to 60% by use of the novel RT-qPCR. The RT-qPCR assay described herein allows rapid and sensitive detection of Atlantic CeMV strains, and is potentially suitable for screening of CeMV globally.

Expression of genes encoding resistance in Staphylococcus spp. isolated from bovine subclinical mastitis in Brazil.

INTRODUCTION: Staphylococci are the most important agents associated with bovine mastitis. This study aimed at characterizing resistance factors to antimicrobials in Staphylococcus spp. isolated from the milk of cows with subclinical mastitis. METHODOLOGY: In vitro resistance of 243 Staphylococcus spp. isolates to antimicrobials commonly used in clinical practice was evaluated. The detection and expression of genes encoding resistance mecA (gene encoding penicillin binding protein 2a) mecALGA251 (mecA homologue), blaZ (gene encoding penicillin resistance), femA and femB (genes encoding essential factors - A and B - for the expression of methicillin resistance) and aacA-aphD (gene encoding for a bifunctional enzyme that confers resistance to gentamicin) using PCR and RT-PCR was investigated. RESULTS: One or more genes encoding resistance to different antimicrobials were detected in 184 Staphylococcus spp. SAMPLES: The femA and femB genes were the most frequent. Regarding the variables' detection (N = number of strains) and expression (% of strains), the following results were obtained: blaZ (N = 40 - 82.5%), femA (N = 147 - 47.6%), aacAaphD (N = 30 - 43.3%), femB (N = 138 - 29.7%), mecA (N = 33 - 27.3%), mecALGA251 (N = 01 - 0.0%). There was a higher occurrence of phenotypic resistant strains for amoxicillin, ampicillin and penicillin in isolates positive for detection and/or expression of blaZ gene when compared with the other genes. CONCLUSIONS: The present study provides new information on genotypic traits of Staphylococcus isolates from bovine subclinical mastitis especially regarding the evaluation of expression of genes associated with antimicrobial resistance in Staphylococcus spp. using molecular tools.

Identification of Pathogenic Leptospira Species in the Urogenital Tract of Water Buffaloes (Bubalus bubalis) From the Amazon River Delta Region, Brazil.

In the current context of deforestation and fire in the Amazon, buffaloes could be a cost-effective and sustainable alternative for cattle production in the region, as they can convert low-quality foods and be raised in floodplain areas. However, little is known about the reproductive diseases that affect these animals; thus, the purpose of this study was to perform the molecular characterization of Leptospira spp. in the urogenital tract of water buffaloes (Bubalus bubalis) raised in the Amazon River Delta region in Brazil. Samples were collected from 114 kidneys, 204 ovaries, and 160 uterine swabs of slaughtered buffaloes in the Macapá microregion of Amapá State (Brazil) and were subjected to PCR to detect bacterial DNA. Positive amplicons were sequenced to identify Leptospira species. Among the total samples, 11/473 were PCR positive (2.3%), including 10 kidney samples and one uterine swab sample. DNA sequencing identified two pathogenic species from the kidney samples: L. interrogans, accounting for 60.0% (6/10) of these samples, and L. borgpetersenii, accounting for 20.0% (2/10), while 20.0% (2/10) were identified only at the genus level. The bacterium in the uterine swab sample was identified as L. interrogans with genetic proximity to strains belonging to the serovar Hardjo. This is the first report of leptospires species identified in buffaloes from the Amazon River Delta region and revealed that these animals may be carriers of different pathogenic Leptospira species, similar to bovines, including showing genital colonization.

Feline immunodeficiency virus in Northern Ceará, Brazil.

OBJECTIVES: The objectives of this study were to confirm the prevalence of feline immunodeficiency virus (FIV) infection in domestic cats in the region north of Ceará, Brazil, and to determine the factors associated with infection and the major circulating subtypes of the virus in this area. METHODS: Samples from 148 cats were collected and tested using anti-FIV antibody screening, with confirmation of positive results by PCR. Univariate analysis was performed considering the epidemiological characteristics and FIV status. Sequencing and phylogenetic analysis of the gag and pol genes were performed to confirm the FIV subtype. RESULTS: Nine cats (6.1%) tested positive for FIV - one female (0.7%) and eight males (5.4%). Male cats were significantly more likely to be infected (P <0.05). Phylogenetic analysis of gag and pol gene sequences indicated that the FIV isolates circulating in the study area belonged to subtype B. CONCLUSIONS AND RELEVANCE: In this study, we demonstrated a low prevalence for FIV in the northwest of Ceará, north-eastern Brazil. Male sex is a significant risk factor for FIV infection and the best predictive factor for FIV status. All isolates examined in this study clustered within subtype B, which is the predominant subtype in Brazil. This is the first report of genetic characterization of FIV in the state of Ceará, Brazil.

Gonadal pathogenicity of an infectious bronchitis virus strain from the Massachusetts genotype.

An outbreak of infectious bronchitis caused by the IBVPR03 strain of the Massachusetts genotype affected H-120 vaccinated laying hens in South Brazil. We investigated the cross protection of the vaccine by assessing the traqueal ciliostasis, virus recovery, and histopathological changes typically observed in the respiratory tract. Although the IBVPR03 strain is S1-genotyped as Massachusetts with a high genomic similarity to the H-120 vaccine strains, surprisingly, we found no tropism or pathogenicity to the trachea in birds infected with this strain. On the other hand, we observed ovarian and testicle lesions. Here, we show that, despite belonging in the Massachusetts genotype, the IBVPR03 pathotype differs from the expected respiratory pattern, causing instead marked histopathological changes in the gonads, so far not associated with this group.

Circulating Leptospira species identified in cattle of the Brazilian Amazon.

The present study aimed to detect the most prevalent serogroups and circulating Leptospira species in cows from Brazilian Amazon. Samples of blood serum, urine and kidney of 208 animals were collected at a municipal slaughterhouse in the Baixo Tocantins region of Pará State, Northern Brazil. The tests used were microscopic agglutination test (MAT), bacteriological isolation, polymerase chain reaction (PCR) and DNA sequencing. The frequency of MAT-reactive cows was 46.6% (97/208) with titers ranging from 100 to 3200, being Sejroe serogroup the most prevalent. There was no Leptospira isolation, but the DNA of bacterium was detected in 5.8% (12/208) of the kidney and in 14.9% (31/208) of the urine samples. DNA sequencing was performed directly from PCR products of 30 samples (3 kidneys and 27 urines), with identification of four different species: L. borgpetersenii with 56.7% (17/30), followed by L. kirschneri with 13.3% (4/30), L. interrogans with 6.7% (2/30), L. santarosai with 3.3% (1/30), and 20.0% (6/30) of samples were identified only at the genus level. These results reveal a diversity and peculiarity for bovine leptospirosis in the Amazon region, mainly due to the low frequency of L. santarosai and more surprising, the presence of L. kirschneri, differently of what is observed in other regions of Brazil.

Gonadal pathogenicity of an infectious bronchitis virus strain from the Massachusetts genotype

An outbreak of infectious bronchitis caused by the IBVPR03 strain of the Massachusetts genotype affected H-120 vaccinated laying hens in South Brazil. We investigated the cross protection of the vaccine by assessing the traqueal ciliostasis, virus recovery, and histopathological changes typically observed in the respiratory tract. Although the IBVPR03 strain is S1-genotyped as Massachusetts with a high genomic similarity to the H-120 vaccine strains, surprisingly, we found no tropism or pathogenicity to the trachea in birds infected with this strain. On the other hand, we observed ovarian and testicle lesions. Here, we show that, despite belonging in the Massachusetts genotype, the IBVPR03 pathotype differs from the expected respiratory pattern, causing instead marked histopathological changes in the gonads, so far not associated with this group.

Gonadal pathogenicity of an infectious bronchitis virus strain from the Massachusetts genotype

An outbreak of infectious bronchitis caused by the IBVPR03 strain of the Massachusetts genotype affected H-120 vaccinated laying hens in South Brazil. We investigated the cross protection of the vaccine by assessing the traqueal ciliostasis, virus recovery, and histopathological changes typically observed in the respiratory tract. Although the IBVPR03 strain is S1-genotyped as Massachusetts with a high genomic similarity to the H-120 vaccine strains, surprisingly, we found no tropism or pathogenicity to the trachea in birds infected with this strain. On the other hand, we observed ovarian and testicle lesions. Here, we show that, despite belonging in the Massachusetts genotype, the IBVPR03 pathotype differs from the expected respiratory pattern, causing instead marked histopathological changes in the gonads, so far not associated with this group.

Development and validation of a modified TaqMan based real-time PCR assay targeting the lipl32 gene for detection of pathogenic Leptospira in canine urine samples

Abstract A modified TaqMan real-time polymerase chain reaction targeting a 138 bp fragment within the lipl32 gene was developed to identify exclusively pathogenic Leptospira spp. in dog urine samples. Thirty-five samples from dogs with suspected clinical leptospirosis and 116 samples from apparently healthy dogs were tested for presence of leptospiral DNA using the TaqMan-based assay. The results were compared with those from a well-established conventional PCR targeting the 16S RNA encoding gene associated with nucleotide sequencing analysis. The overall agreement between the assays was 94.8% (confidence interval [CI] 95% 88-100%). The newly developed assay presented 91.6% (CI 95% 71.5-98.5%) relative sensitivity (22[+] lipl32 PCR/24[+] 16S RNA and sequencing), 100% (CI 95% 96.3-100%) relative specificity and 98.7% accuracy (CI 95% 94.8-100%). The lipl32 assay was able to detect and quantify at least 10 genome equivalents/reaction. DNA extracted from 17 pathogenic Leptospira spp., 8 intermediate/saprophytic strains and 21 different pathogenic microorganisms were also tested using the lipl32 assay, resulting in amplification exclusively for pathogenic leptospiral strains. The results also demonstrated high intra and inter-assay reproducibility (coefficient of variation 1.50 and 1.12, respectively), thereby qualifying the newly developed assay as a highly sensitive, specific and reliable diagnostic tool for leptospiral infection in dogs using urine specimens.

First detection of feline hemoplasmas in free-ranging jaguars (Panthera onca).

Species of hemoplasmas have been described worldwide, but little information is available for wild felids. Between February 2000 and January 2010, blood samples were collected from 30 jaguars (Panthera onca) and 22 domestic cats (Felis catus) from the Cerrado, Pantanal and Amazon biomes of Brazil. In all samples molecular tests were performed for Mycoplasma haemofelis/Mycoplasma haemocanis (Mhf/Mhc), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus Mycoplasma turicensis' (CMt). Twenty-two (73.4%) jaguars and four domestic cats (18.2%) tested positive for infection with at least one feline hemoplasma: 73.4% jaguars from the three areas were positive for CMhm, 13.6% jaguars from the Pantanal and 50.0% from the Amazon were positive for Mhf/Mhc, and 9.1% of individuals from the Pantanal tested positive for CMt. Domestic cats from the Cerrado (28.6%) and the Pantanal (30.0%) were positive for feline hemoplasma. All but one jaguar from the three sites are healthy. One female adult jaguar showed low body weight and dehydration. This is the first record of feline hemoplasmas in free-ranging jaguars. The high prevalence of CMhm suggest the participation of jaguars in the maintenance of this hemoplasma in nature. Although susceptible to Mhf/Mhc and CMt, jaguars did not appear to participate in the maintenance of these agents in the environment. The involvement of domestic cats in the transmission of any of these hemoplasmas cannot be excluded.

Development and validation of a modified TaqMan based real-time PCR assay targeting the lipl32 gene for detection of pathogenic Leptospira in canine urine samples.

A modified TaqMan real-time polymerase chain reaction targeting a 138bp fragment within the lipl32 gene was developed to identify exclusively pathogenic Leptospira spp. in dog urine samples. Thirty-five samples from dogs with suspected clinical leptospirosis and 116 samples from apparently healthy dogs were tested for presence of leptospiral DNA using the TaqMan-based assay. The results were compared with those from a well-established conventional PCR targeting the 16S RNA encoding gene associated with nucleotide sequencing analysis. The overall agreement between the assays was 94.8% (confidence interval [CI] 95% 88-100%). The newly developed assay presented 91.6% (CI 95% 71.5-98.5%) relative sensitivity (22[+] lipl32 PCR/24[+] 16S RNA and sequencing), 100% (CI 95% 96.3-100%) relative specificity and 98.7% accuracy (CI 95% 94.8-100%). The lipl32 assay was able to detect and quantify at least 10 genome equivalents/reaction. DNA extracted from 17 pathogenic Leptospira spp., 8 intermediate/saprophytic strains and 21 different pathogenic microorganisms were also tested using the lipl32 assay, resulting in amplification exclusively for pathogenic leptospiral strains. The results also demonstrated high intra and inter-assay reproducibility (coefficient of variation 1.50 and 1.12, respectively), thereby qualifying the newly developed assay as a highly sensitive, specific and reliable diagnostic tool for leptospiral infection in dogs using urine specimens.

Felis catus gammaherpesvirus 1 (FcaGHV1) and coinfections with feline viral pathogens in domestic cats in Brazil / Ocorrência de Felis catus gammaherpesvirus 1 (FcaGHV1) e coinfecções com patógenos virais felinos em gatos domésticos no Brasil

ABSTRACT: Felis catus gammaherpesvirus 1 (FcaGHV1) may causes an asymptomatic infection that result in an efficient transmission and subsequently dissemination of the virus in feline population. This study used molecular detection by qPCR (quantitative PCR) based on DNA polymerase gene fragment amplification to evaluate the occurrence of FcaGHV1 and its correlation with other feline viral pathogens, such as Carnivore protoparvovirus 1 (CPPV-1), Felid alphaherpesvirus 1 (FeHV-1), and feline retroviruses such as feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). Of the 182 blood samples evaluated 23.6% (43/182) were positives for FcaGHV1. Approximately 37.9% (33/87) of the samples that tested positive for retrovirus were also were positive for FcaGHV1 infection (P<0.0001). Among FIV-infected samples, 49% (24/49) were positive for FcaGHV1 (P<0.0001). FcaGHV1 infection was not associated with FeLV (P>0.66) or CPPV-1 (P>0.46) coinfection. All samples were negative for FeHV-1. Male felines were significantly associated to FcaGHV1 (P<0.0001) and their risk of infection with FcaGHV1 was about of 7.74 times greater compared to females. Kittens (≤ 1year) were the least affected by FcaGHV1 infection, being verified a rate of 7.7% (4/52). Therefore, male cats over one year old and infected with FIV were considerably more likely to be infected with FcaGHV1. To our knowledge, this is the first study to report the occurrence and molecular detection of FcaGHV1 infection in domestic cats in Brazil and in South America.

RESUMO: Felis catus gammaherpesvirus 1 (FcaGHV1) pode causar uma infecção assintomática, que resulta em uma transmissão eficiente e consequente disseminação do virus na população felina. Este estudo utilizou a detecção molecular por qPCR (PCR quantitativa) baseado na amplificação de um fragmento do gene da DNA polimerase para avaliar a ocorrência de FcaGHV1, sendo correlacionado a outros patógenos virais felinos como Carnivore protoparvovirus 1 (CPPV-1), Felid alphaherpesvirus 1 (FeHV-1) e aos retrovírus felinos como vírus da imunodeficiência felina (FIV) e vírus da leucemia felina (FeLV). Das 182 amostras de sangue avaliadas, 23,6% (43/182) foram positivas para FcaGHV1. Aproximadamente 37,9% (33/87) das amostras positivas para retrovirus também foram positivas para FcaGHV1 (P<0,0001). Entre as amostras FIV-infectadas, 49% (24/49) foram positivas para FcaGHV1 (P<0,0001). A infecção por FcaGHV1 não foi associada à coinfecção por FeLV (P>0,66) e CPPV-1 (P>0,46). Todas as amostras foram negativas para FeHV-1. Felinos machos foram significativativamente associados à infecção por FcaHV1 (P <0,0001) e o risco de infecção com FcaGHV1 foi aproximadamente 7,74 vezes maior comparados às femeas. Os filhotes (≤1 ano) foram os menos acometidos pela infecção por FcaGHV1 sendo verificado uma proporção de 7.7% (4/52). Assim, gatos machos com mais de um ano de idade e infectados por FIV foram, consideravelmente, mais susceptíveis a serem infectados com FcaGHV1. Para nosso conhecimento, este é o primeiro estudo que relata a ocorrência de infecção e detecção molecular de FcaGHV1 em gatos domésticos no Brasil e na América do Sul.

Short interfering RNAs targeting a vampire-bat related rabies virus phosphoprotein mRNA

Abstract The aim of this study was to assess the in vitro and in vivo effects of short-interfering RNAs (siRNAs) against rabies virus phosphoprotein (P) mRNA in a post-infection treatment for rabies as an extension of a previous report (Braz J Microbiol. 2013 Nov 15;44(3):879-82). To this end, rabies virus strain RABV-4005 (related to the Desmodus rotundus vampire bat) were used to inoculate BHK-21 cells and mice, and the transfection with each of the siRNAs was made with Lipofectamine-2000™. In vitro results showed that siRNA 360 was able to inhibit the replication of strain RABV-4005 with a 1 log decrease in virus titter and 5.16-fold reduction in P mRNA, 24 h post-inoculation when compared to non-treated cells. In vivo, siRNA 360 was able to induce partial protection, but with no significant difference when compared to non-treated mice. These results indicate that, despite the need for improvement for in vivo applications, P mRNA might be a target for an RNAi-based treatment for rabies.

Hepatozoon SPP. Infect Free-Ranging Jaguars (Panthera onca) in Brazil.

This study investigated the presence of Hepatozoon spp. in jaguars ( Panthera onca ) and domestic animals in the Cerrado, Amazon, and Pantanal biomes of Brazil. Between February 2000 and January 2010, blood samples were collected from 30 jaguars, 129 domestic dogs ( Canis lupus familiaris), and 22 domestic cats ( Felis catus ) for molecular tests. All of the jaguars from the Pantanal (n = 22) and Cerrado (n = 4) and 3 of 4 jaguars from the Amazon were positive for Hepatozoon spp. Domestic dogs (62.8%) and cats (31.8%) were also positive for the agent. Hepatozoon nucleotide sequences from jaguars and domestic cats grouped with other Hepatozoon felis, whereas Hepatozoon from domestic dogs showed high similarity to Hepatozoon canis. Different species of Amblyomma were identified as parasitizing the jaguars and may act as vectors for Hepatozoon spp. Jaguars from the 3 sites were healthy and did not seem to be threatened by the hemoparasite within its population or environments. Most likely, jaguars play an important role in the maintenance of Hepatozoon spp. in nature.

Is the free-ranging jaguar (Panthera onca) a reservoir for Cytauxzoon felis in Brazil?

This study investigated the occurrence of Cytauxzoon felis and Babesia spp. in free-ranging jaguars (Panthera onca), domestic dogs (Canis lupus familiaris) and domestic cats (Felis catus) from the Cerrado, Amazon and Pantanal biomes of Brazil. Blood samples were collected from 30 jaguars, 129 dogs and 22 cats for detection of the 18S rRNA genes of piroplasmids. All of the jaguars from the Pantanal (n=22) and Cerrado (n=4) and three of four jaguars from the Amazon were positive for C. felis, but no dogs or cats were positive for the agent. All of the jaguars and domestic cats were negative for Babesia spp., while dogs from the Cerrado (7.9%; 5/63) and Amazon (10.6%; 5/47) biomes tested positive for the hemoparasite. Cytauxzoon nucleotide sequences detected were closely related to C. felis; and Babesia nucleotide sequences showed 100% of identity with Babesia vogeli. Although the pathogenicity of Cytauxzoon spp. genotypes that circulate in Brazil is still unknown, free-ranging jaguars probably play an important role in the maintenance of C. felis in nature. In addition, even though there is no evidence of the circulation of Babesia spp. between jaguars and dogs, the presence of this hemoparasite should be monitored in jaguar populations.

Short interfering RNAs targeting a vampire-bat related rabies virus phosphoprotein mRNA.

The aim of this study was to assess the in vitro and in vivo effects of short-interfering RNAs (siRNAs) against rabies virus phosphoprotein (P) mRNA in a post-infection treatment for rabies as an extension of a previous report (Braz J Microbiol. 2013 Nov 15;44(3):879-82). To this end, rabies virus strain RABV-4005 (related to the Desmodus rotundus vampire bat) were used to inoculate BHK-21 cells and mice, and the transfection with each of the siRNAs was made with Lipofectamine-2000™. In vitro results showed that siRNA 360 was able to inhibit the replication of strain RABV-4005 with a 1log decrease in virus titter and 5.16-fold reduction in P mRNA, 24h post-inoculation when compared to non-treated cells. In vivo, siRNA 360 was able to induce partial protection, but with no significant difference when compared to non-treated mice. These results indicate that, despite the need for improvement for in vivo applications, P mRNA might be a target for an RNAi-based treatment for rabies.

Molecular stability of a vaccine strain of Canine coronavirus after serial passages in A72 cells / Estabilidade molecular de uma amostras vacinal de Coronavírus canino após passagens seriadas em células A72

Canine coronavirus (CCoV) exists in types I and II and infects dogs leading mainly to enteritis, though type II has already been associated with generalized and highly lethal infection. A CCoV-type II inactivated vaccine produced in A72 canine cells is available worldwide and largely used, though the molecular stability after serial passages of vaccine seeds is unknown. This article reports the evolution of the CCoV-II vaccine strain 1-71 in A72 cells based on partial S gene sequencing, showing the predominance of neutral evolution and the occurrence of four sites under purifying selection. Thus, cell-adapted strains of CCoV-II may be genetically stable after serial passages in a same cell line due to a stable virus-host relationship.(AU)

O Coronavírus canino (CCoV) ocorre como tipos I e II e infecta cães, levando principalmente a enterite, apesar do tipo II já ter sido associado à infecção generalizada e altamente letal. Uma vacina de CCoV-II inativada produzida em células caninas A72 é disponível mundialmente e largamente utilizada, apesar da sua estabilidade molecular após passagens seriadas de sementes vacinais ser desconhecida. Este artigo relata a evolução da amostra vacinal CCoC-II 1-71 em células A-72 com base em sequenciamento parcial do gene S, demonstrando predomínio de evolução neutra e a ocorrência de quaro sítios sob seleção purificante. Portanto, amostras de CCoV-II adaptadas a cultivos celulares podem ser estáveis geneticamente após passagens seriadas em uma mesma linhagem celular devido à existência de uma relação estável vírus-hospedeiro.(AU)

Group A rotavirus in Brazilian bats: description of novel T15 and H15 genotypes.

This study aimed to survey for group A rotaviruses (RVA) in bats from Brazil and to perform phylogenetic inferences for VP4, VP7, NSP3, NSP4 and NSP5 genes. RVA was found in 9.18 % (28/305) of tested samples. The partial genotype constellation of a Molossus molossus RVA strain was G3-P[3]-Ix-Rx-Cx-Mx-Ax-Nx-T3-E3-H6, and that of a Glossophaga soricina RVA strain was G20-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-T15-Ex-H15. These findings demonstrate an important role of bats in RVA epidemiology and provide evidence of participation of bat RVA strains in interspecies transmission and reassortment events.