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1.
Trop Anim Health Prod ; 54(2): 113, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35217986

RESUMEN

Rotavirus (RV) infections represent a significant cause of enteritis and diarrhea in avian species and pose a major concern for the poultry industry. However, the prevalence of rotavirus infections among birds is poorly understood. Stool samples were collected from laying and broiler hens from commercial poultry farms in the states of Rio de Janeiro and Espírito Santo, Southwest region of Brazil, for detection of rotavirus species F and G (RVF and RVG, respectively) by reverse transcription polymerase chain reaction. RV was detected in 11.7% (38/325) of samples: 35 samples were positive for RVF and 3 for RVG. RVF was detected in 15 samples from Rio de Janeiro and 23 samples from Espírito Santo. RVG was detected in 3 samples from Espírito Santo. All the positive samples were from asymptomatic broiler chickens. The prevalence of RV infection in these flocks was high, especially considering that the birds had no apparent clinical disease. Silent circulation in the herds signifies the need for a continuous surveillance program to guide measures to control and prevent this viral infection. Continuous monitoring of pathogens is crucial to ensure greater productivity on poultry farms.


Asunto(s)
Enfermedades de las Aves de Corral , Infecciones por Rotavirus , Rotavirus , Animales , Brasil/epidemiología , Pollos , Femenino , Enfermedades de las Aves de Corral/epidemiología , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria
2.
Eur J Clin Microbiol Infect Dis ; 38(1): 135-139, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30338464

RESUMEN

Despite the growing importance of infections caused by the human polyomaviruses (HPyVs), information about their transmission, pathogenesis, and epidemiology is scarce. The objective of this work was to evaluate the excretion and distribution of HPyV (HPyV1-HPyV4 [former BKPyV, JCPyV, KIPyV, and WUPyV, respectively]) among asymptomatic individuals from different geographic regions in Brazil, in order to verify the existence of distinct epidemiologic patterns among the Brazilian population. Saliva samples from 889 healthy volunteers living in nine locations in Brazil were analyzed by real-time polymerase chain reaction (PCR) to detect HPyV1-4. Among 889 participants, 346 (39%) had evidence of infection with one or more HPyV species: 127 (14.3%) had HPyV1 only; 70 (7.9%) had HPyV3 only; 60 (6.7%) had HPyV4 only, and 25 (2.8%) had HPyV2 only. Coinfections were detected in 64 participants (7.3%). Although HPyV excretion was detected in samples from all locations, the frequency and distribution of viral species varied significantly. The epidemiologic findings presented demonstrate that the four HPyV species studied are circulating in five geographic regions of Brazil. Salivary excretion of these viruses appears common among healthy Brazilians. The distribution of viral species varies considerably between regions as well as within regions.


Asunto(s)
Infecciones por Polyomavirus/epidemiología , Poliomavirus/genética , Adolescente , Adulto , Anciano , Infecciones Asintomáticas/epidemiología , Brasil/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Infecciones por Polyomavirus/virología , Saliva/virología , Adulto Joven
3.
Vet Res Commun ; 48(2): 743-748, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37878188

RESUMEN

Rotavirus (RV) outbreaks can cause significant economic losses in the livestock and poultry industries. Stool samples were collected from asymptomatic laying and broiler chickens from commercial poultry farms in the states of Rio de Janeiro and Espírito Santo in southeastern Brazil for detection of RV species A and D (RVA and RVD, respectively) by reverse transcription polymerase chain reaction. RV was detected in 10.5% (34/325) of samples: 22 (64.7%) were positive for RVA and nine (26.5%) for RVD, while three (8.8%) exhibited coinfections with both viruses. Sequence analysis of a VP6 fragment from seven RVA-positive samples identified the I11 genotype in all samples. Information regarding avian RV epidemiology is still scanty, despite the high prevalence of RV infections in several bird species and subsequent economic impact. Consequently, monitoring infections caused by avian RVs, especially in commercial birds, is essential not only to provide new and relevant information regarding the biology, epidemiology, and evolution of these viruses, but also to facilitate the implementation of preventive measures.


Asunto(s)
Infecciones por Rotavirus , Rotavirus , Animales , Rotavirus/genética , Pollos , Brasil/epidemiología , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria , Filogenia , Genotipo
4.
J Med Virol ; 85(1): 144-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23154878

RESUMEN

The aim of this study was to investigate and compare the frequency of BKV, JCV, WUV, and KIV in the saliva of healthy individuals. Samples were analyzed for the presence of polyomaviruses (BKV, JCV, WUV, and KIV) DNA by real-time PCR. Of the 291 samples tested, 71 (24.3%) were positive for at least one of the screened polyomaviruses. Specifically, 12.7% (37/291) were positive for WUV, 7.2% (21/291) positive for BKV, 2.4% (7/291) positive for KIV, and 0.3% (1/291) positive for JCV. BKV and WUV co-infections were detected in 1.7% (5/291) of individuals. No other co-infection combinations were found. The mean number of DNA copies was high, particularly for WUV and BKV, indicating active replication of these viruses. Polyomavirus detection was higher among individuals 15-19 years of age (46.0%; 23/50) and ≥50 years of age (33.3%; 9/27). However, the detection rate in the first group was almost 1.7× greater than the latter. WUV infections were more frequent in individuals between the ages of 15 and 19 years and the incidence decreased with age. By contrast, BKV excretion peaked and persisted during the third decade of life and KIV infections were detected more commonly in subjects ≥50 years old. These findings reinforced the previous hypotheses that saliva may be a route for BKV transmission, and that the oral cavity could be a site of virus replication. These data also demonstrated that JCV, WUV, and KIV may be transmitted in a similar fashion.


Asunto(s)
Infecciones por Polyomavirus/virología , Poliomavirus/aislamiento & purificación , Saliva/virología , Esparcimiento de Virus , Adolescente , Adulto , Factores de Edad , Anciano , Portador Sano/epidemiología , Portador Sano/virología , Coinfección/epidemiología , Coinfección/virología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Poliomavirus/genética , Infecciones por Polyomavirus/epidemiología , Prevalencia , Carga Viral , Adulto Joven
5.
Viruses ; 15(5)2023 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-37243175

RESUMEN

Avian rotaviruses (RVs) are important etiologic agents of gastroenteritis in birds. In general, avian RVs are understudied; consequently, there is a paucity of information regarding these viruses. Therefore, the characterization of these viral species is highly relevant because more robust information on genetic, epidemiologic, and evolutionary characteristics can clarify the importance of these infections, and inform efficient prevention and control measures. In this study, we describe partial genome characterizations of two avian RV species, RVF and RVG, detected in asymptomatic poultry flocks in Brazil. Complete or partial sequences of at least one of the genomic segments encoding VP1, VP2, VP4, VP6, VP7, NSP1, NSP4, NSP4, or NSP5 of 23 RVF and 3 RVG strains were obtained, and demonstrated that multiple variants of both RVF and RVG circulate among Brazilian poultry. In this study, new and important information regarding the genomic characteristics of RVF and RVG is described. In addition, the circulation of these viruses in the study region and the genetic variability of the strains detected are demonstrated. Thus, the data generated in this work should help in understanding the genetics and ecology of these viruses. Nonetheless, the availability of a greater number of sequences is necessary to advance the understanding of the evolution and zoonotic potential of these viruses.


Asunto(s)
Infecciones por Rotavirus , Rotavirus , Animales , Rotavirus/genética , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/genética , Brasil/epidemiología , Aves de Corral , Pollos , Filogenia , Genoma Viral , Genotipo
6.
Top Companion Anim Med ; 49: 100667, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35417783

RESUMEN

Rotaviruses species A (RVA) are etiological agents of diarrhoea and are considered zoonotic viruses; yet the epidemiology of RVA among pet animals is largely unknown. RVA was detected in 38 of 308 faecal samples (12.3%) from pet, sheltered, or stray dogs and cats in 2 municipalities of Rio de Janeiro state, Brazil. The results indicated that these viruses are common in canine and feline populations and underscore the importance of improved monitoring of common pathogens in companion animals, with increased awareness of the potential for interspecies transmission events.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Infecciones por Rotavirus , Animales , Brasil/epidemiología , Enfermedades de los Gatos/epidemiología , Gatos , Enfermedades de los Perros/epidemiología , Perros , Genotipo , Filogenia , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria
7.
J Vet Diagn Invest ; 33(1): 129-135, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33090086

RESUMEN

Rotaviruses (RVs) have been identified as one of the main infectious causes of diarrhea in young pigs. We determined the prevalence of rotavirus A (RVA), C (RVC), and H (RVH) in pigs on a Brazilian farm. Samples were screened by reverse-transcription (RT)-PCR, and samples positive for RVA were genotyped by PCR amplification and sequencing analysis. Of the 329 fecal samples analyzed, 102 (30.9%) were positive for RV, 25 (7.6%) contained RVA only, 32 (9.7%) contained RVC only, and 31 (9.4%) contained RVH only. Co-circulation, the presence of ≥ 2 RVs in a sample, was detected in 14 (4.2%) samples. Of the 15 animals with diarrhea, 6 (40%) were positive for RV, and of the 314 asymptomatic animals, 96 (30.6%) were positive for RV; there was no statistically significant difference between the 2 groups (p = 0.441). Genotyping of RVA strains showed co-circulation of genotypes G1, G3, G9-P[8]-I1, and I2-E1. Phylogenetic analysis showed that some of the RVA genotypes found in pigs had high percentages of identity when compared with reference strains from humans, which suggests interspecies transmission. Because RVs may be zoonotic, excretion of RVs into the environment can result in transmission to agricultural workers causing interspecies infections and allowing the emergence of new reassorted viruses.


Asunto(s)
Infecciones por Rotavirus/veterinaria , Rotavirus/aislamiento & purificación , Enfermedades de los Porcinos/epidemiología , Zoonosis/epidemiología , Animales , Brasil/epidemiología , Diarrea/veterinaria , Heces/virología , Genotipo , Prevalencia , Rotavirus/clasificación , Rotavirus/genética , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/transmisión , Infecciones por Rotavirus/virología , Sus scrofa , Porcinos , Enfermedades de los Porcinos/transmisión , Enfermedades de los Porcinos/virología , Zoonosis/transmisión , Zoonosis/virología
8.
Braz J Microbiol ; 51(2): 585-591, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31667802

RESUMEN

The human polyomaviruses (HPyVs) 10 and 11 have been detected in faecal material and are tentatively associated with diarrhoeal disease. However, to date, there are insufficient data to confirm or rule out this association, or even to provide basic information about these viruses, such as how they are distributed in the population, the persistence sites and their pathogenesis. In this study, we analysed stool specimens from Brazilian children with and without acute diarrhoea to investigate the excretion of HPyV10 and HPyV11 as well as their possible associations with diarrhoea. A total of 460 stool specimens were obtained from children with acute diarrhoea of unknown aetiology, and 106 stool specimens were obtained from healthy asymptomatic children under 10 years old. Samples were collected during the periods of 1999-2006, 2010-2012 and 2016-2017, and found previously to be negative for other enteric viruses and bacteria. The specimens were screened for HPyV10 and HPyV11 DNA by the polymerase chain reaction (PCR). Randomly selected positive samples were sequenced to confirm the presence of HPyV10 and HPyV11. The sequenced strains showed a percent of nucleotide identity of 93.4-99.6% and 85.5-98.9% with the reference HPyV10 and HPyV11 strains, respectively, confirming the PCR results. HPyV10 and HPyV11 were detected in 7.2% and 4.7% of the stool specimens from children with and without diarrhoea, respectively. The prevalence of both viruses was the same among children with diarrhoea and healthy children. There was also no difference between boys and girls or the degree of disease (severe, moderate or mild) among groups. Phylogenetic analysis showed that all of the genotypes described so far for HPyV10 and HPyV11 circulate in Rio de Janeiro. Our results do not support an association between HPyV10 and HPyV11 in stool samples and paediatric gastroenteritis. Nevertheless, the excretion of HPyV10 and HPyV11 in faeces indicates that faecal-oral transmission is possible.


Asunto(s)
Diarrea/virología , Heces/virología , Infecciones por Polyomavirus/virología , Poliomavirus/genética , Poliomavirus/aislamiento & purificación , Brasil/epidemiología , Niño , Preescolar , ADN Viral/genética , Diarrea/epidemiología , Femenino , Gastroenteritis/virología , Humanos , Lactante , Recién Nacido , Masculino , Filogenia , Poliomavirus/clasificación , Infecciones por Polyomavirus/epidemiología
10.
J Infect Dev Ctries ; 10(3): 269-74, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-27031459

RESUMEN

INTRODUCTION: Infections, particularly diarrheal infections, are a major cause of neonatal death in South American camelids. The aim of this study was to identify the pathogens that could have caused the recent diarrhea outbreak among the alpacas in Silli, Cusco, located in the southern Peruvian highland. METHODOLOGY: Spleen, kidney, and intestine tissue along with fecal and intestinal lavage samples were obtained from 50 one- to five-week-old alpacas and analyzed for the presence of parasites, bacteria, and viruses. RESULTS: Laboratory testing of the 50 crias included in this study revealed that 80% were infected with Eimeria spp., 40% with coronavirus, 34% with E. coli, 32% with rotavirus, 22% with Clostridium spp., and 20% with Cryptosporidium spp. Of these 50 alpaca crias, 20 presented with a single infection (19 positive for Eimeria spp. and 1 positive for rotavirus). Co-infections with up to four pathogens occurred in 60% of the samples. The significance of such infections is not clear, but it is noteworthy that the animals suffering from necrotic and/or hemorrhagic enteritis presented with quadruple infections. It is likely that co-infections increase the severity of the disease. CONCLUSIONS: These data show that multiple pathogens circulate among young alpaca crias and could be associated with diarrheal disease in these animals. The findings from this study warrant the provision of subsidies for future assessment of the potential economic impact of these infections on the productivity of the Peruvian alpaca industry.


Asunto(s)
Bacterias/aislamiento & purificación , Camélidos del Nuevo Mundo , Diarrea/veterinaria , Brotes de Enfermedades , Parásitos/aislamiento & purificación , Virus/aislamiento & purificación , Animales , Diarrea/epidemiología , Diarrea/etiología , Perú/epidemiología
11.
Carbohydr Polym ; 101: 313-23, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24299779

RESUMEN

The anti-HMPV (human metapneumovirus) activity was determined for sulfated dl-hybrid galactans obtained from the red seaweed Cryptonemia seminervis and their depolymerized products obtained by reductive partial hydrolysis. Structural studies carried out in three homogeneous depolymerized fractions DS-1, DS-2e and DS-3 (Mw of 51.6-63.8 kDa) showed that these galactans present different chemical characteristics, as monosaccharide composition, content of sulfate groups (14.1-29.9%) and agaran:carrageenan molar ratio diads, 2.7:1 for DS-1 and DS-2e and 1:1 for DS-3. The sulfate groups are located principally on C-2 of ß-d-galactopyranose and 4,6-O-(1'-carboxyethylidene)-ß-d-galactopyranose residues and on C-6 of α-galactose residues. Sulfated dl-galactans and their depolymerized products exhibited antiviral activity at a very early stage of the viral infection cycle. All fractions, except DS-2e inhibited HMPV replication by binding to the viral particle. Besides depolymerized galactans DS-2e and DS-3 inhibited the recognition of cell receptor by HMPV and penetration to the host cell, respectively.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Galactanos/química , Galactanos/farmacología , Metapneumovirus/efectos de los fármacos , Rhodophyta/química , Sulfatos/química , Animales , Antivirales/toxicidad , Línea Celular , Galactanos/toxicidad , Humanos , Polimerizacion
12.
Nat Prod Commun ; 4(12): 1693-6, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20120109

RESUMEN

Verbascoside has been isolated form L. speciosa after several different chromatographic methods. After its purification, the structure has been unequivocally established using modern spectroscopic techniques. As for the antiviral activity, the maximum non toxic concentration has been established and this concentration has been used in the anti herpes assay, in vitro. Mechanism of action for this molecule regarding the anti-herpes activity has been studied encompassing the following assays: virucidal activity, cellular receptor assay, penetration assay and intracellular assay, in order to understand the activity for this natural product.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Glucósidos/química , Glucósidos/farmacología , Herpesvirus Humano 1/efectos de los fármacos , Herpesvirus Humano 2/efectos de los fármacos , Lamiaceae/química , Fenoles/química , Fenoles/farmacología , Animales , Antivirales/aislamiento & purificación , Membrana Celular/metabolismo , Chlorocebus aethiops , Glucósidos/aislamiento & purificación , Fenoles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/farmacología , Células Vero
13.
Rev. bras. farmacogn ; 22(4): 714-723, jul.-ago. 2012. tab
Artículo en Inglés | LILACS | ID: lil-640341

RESUMEN

Organic extracts of 36 species of marine algae (sixteen species of Rhodophyta, eight species of Ochrophyta and twelve species of Chlorophyta) from seven locations on the Brazilian coast were evaluated for their anti-HSV-1 and anti-HSV-2 activity resistant to Acyclovir (ACV). Activity tests in crude extracts, followed by the identification of the major compounds present, were performed for all species. The chemical profiles of all crude extracts were obtained by ¹H-NMR and 13C-NMR spectroscopy. The percentage of extracts with antiviral activity was higher for HSV-1 (86.1%) than for HSV-2 (55.5%). The green algae Ulva fasciata and Codium decorticatum both showed the highest activity (99.9%) against HSV-1, with triacylglycerols and fatty acids as the major components. The red alga Laurencia dendroidea showed good activity against HSV-1 (97.5%) and the halogenated sesquiterpenes obtusol and (-)-elatol were identified as the major components in the extract. Against HSV-2, the green alga Penicillus capitatus (Chlorophyta) and Stypopodium zonale (Ochrophyta) were the most active (96.0 and 95.8%). Atomaric acid, a meroditerpene, was identified as the major secondary metabolite in the S. zonale extract. These results reinforce the role of seaweeds as important sources of compounds with the potential to enter into the pipeline for development of new drugs against herpes simplex.

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