85 research outputs found
Brazilian vaccinia virus strains are genetically divergent and differ from the lister vaccine strain.
Vaccinia virus is responsible for an important zoonotic disease affecting dairy cattle and humans in Brazil, but little is known about the origin, epidemiology and evolution of these Brazilian Vaccinia virus strains. In this work, seven Brazilian Vaccinia virus strains and the Lister-derived Brazilian vaccine strain, named Lister-Butantan, were compared based on the sequences of ten host range and virulence related genes. Comparison of Brazilian Vaccinia virus strains with Lister-Butantan revealed several differences. Phylogenetic analyses confirmed the existence of genetically distinct Brazilian Vaccinia virus groups and has not thus far demonstrated a close relationship between Brazilian strains and Lister-Butantan. In this study, the BeAn58058 and SPAn232 strains were grouped together with the Belo Horizonte and Guarani P1 strains. Additionally, genetic polymorphisms in host range and virulence genes as well as differences in the deduced amino acid sequences were detected among Brazilian Vaccinia virus. This genetic diversity may result in a plethora of different biological properties presented by Brazilian Vaccinia virus, including differences in adaptation to the host as well as pathogenic properties. Furthermore, co-circulation of these divergent strains could increase the possibility of recombination events in nature, leading to the formation of new variants with unpredictable pathogenic potential
Brazilian vaccinia virus strains show genetic polymorphism at the ati gene.
Nucleotide sequence comparison of the internal region of the ati gene of members of the Orthopoxvirus genera revealed that this gene is variable among different species, although within members of the same species it is considered to be well conserved. Previous studies indicated that there is genetic variability in the ati gene among some Brazilian Vaccinia virus strains. To further investigate this variability, we performed molecular analysis of the internal region of the ati gene of eight Brazilian Vaccinia virus strains. While the internal region of this gene in one strain was similar to the Western Reserve strain, four strains presented two blocks of deletions in the analyzed region, and the ati gene was almost entirely deleted from three other strains. These findings demonstrate that there is genetic polymorphism within the ati gene among different Brazilian Vaccinia virus strains
Spread of vaccinia virus to cattle herds, Argentina, 2011
To the Editor: Since 1999, several zoonotic outbreaks of vaccinia virus (VACV) infection have been reported in cattle and humans in rural areas of Brazil. The infections have caused exanthematous lesions on cows and persons who milk them, and thus are detrimental to the milk industry and public health services (1,2). In Brazil during the last decade, VACV outbreaks have been detected from the north to the extreme south of the country (1–4). Because Brazil shares extensive boundaries with other South American countries, humans and cattle on dairy and beef-producing farms in those countries may be at risk of exposure to VACV. To determine if VACV has spread from Brazil to Argentina, we investigated the presence of VACV in serum samples from cattle in Argentina.Facultad de Ciencias VeterinariasComisión de Investigaciones Científicas de la provincia de Buenos Aire
Spread of vaccinia virus to cattle herds, Argentina, 2011
To the Editor: Since 1999, several zoonotic outbreaks of vaccinia virus (VACV) infection have been reported in cattle and humans in rural areas of Brazil. The infections have caused exanthematous lesions on cows and persons who milk them, and thus are detrimental to the milk industry and public health services (1,2). In Brazil during the last decade, VACV outbreaks have been detected from the north to the extreme south of the country (1–4). Because Brazil shares extensive boundaries with other South American countries, humans and cattle on dairy and beef-producing farms in those countries may be at risk of exposure to VACV. To determine if VACV has spread from Brazil to Argentina, we investigated the presence of VACV in serum samples from cattle in Argentina.Facultad de Ciencias VeterinariasComisión de Investigaciones Científicas de la provincia de Buenos Aire
A study of the MAYV replication cycle: correlation between the kinetics of viral multiplication and viral morphogenesis
Mayaro virus (MAYV) is mainly found in Central and South America and causes a febrile illness followed by debilitating arthritis and arthralgia similar to chikungunya virus (CHIKV). Infection leads to long-term sequelae with a direct impact on the patient's productive capacity, resulting in economic losses. Mayaro fever is a neglected disease due to the limited epidemiological data. In Brazil, it is considered a potential public health risk with the number of cases increasing every year. Most of our knowledge about MAYV biology is inferred from data obtained from other alphaviruses as well as more recent studies on MAYV. Here, we analyzed the kinetics of viral replication through standard growth curves, quantification of intracellular and extracellular particles, and RNA quantification. We compared transmission electron microscopy data during different stages of infection. This approach allowed us to establish a chronological order of events during MAYV replication and its respective timepoints including cell entry through clathrin-mediated endocytosis occurring at 15-30 min, genome replication at 2-3 h, morphogenesis at 4 hpi, and release at 4-6 hpi. We also present evidence of uncharacterized events such as ribosome reorganization as well as clusters of early viral precursors and release through exocytosis in giant forms. Our work sheds new and specific light on the MAYV replication cycle and may contribute to future studies on the field
Collagen-Based Films Containing Liposome-Loaded Usnic Acid as Dressing for Dermal Burn Healing
The aim of this study was assess the effect of collagen-based
films containing usnic acid as a wound dressing for dermal burn
healing. Second-degree burn wounds were performed in forty-five
Wistar rats, assigned into nine groups: COL—animals treated
with collagen-based films; PHO—animals treated with collagen
films containing empty liposomes; UAL—animals treated with
collagen-based films containing usnic acid incorporated into
liposomes. After 7, 14, and 21 days the animals were euthanized.
On 7th day there was a moderate infiltration of neutrophils, in
UAL, distributed throughout the burn wounds, whereas in COL and
PHO, the severity of the reaction was slighter and still limited
to the margins of the burn wounds. On the 14th day, the
inflammatory reaction was less intense in UAL, with remarkable
plasma cells infiltration. On the 21st day, there was reduction of
the inflammation, which was predominantly composed of plasma cells
in all groups, particularly in UAL. The use of the usnic acid
provided more rapid substitution of type-III for type-I collagen
on the 14th day, and improved the collagenization density on the
21st day. It was concluded that the use of reconstituted bovine
type-I collagen-based films containing usnic acid improved burn
healing process in rats
Oral Health, Temporomandibular Disorder, and Masticatory Performance in Patients with Charcot-Marie-Tooth Type 2
Background. The aim of this study was to evaluate the oral health status of temporomandibular disorders (TMD) and bruxism, as well as to measure masticatory performance of subjects with Charcot-Marie-Tooth type 2 (CMT2). Methods and Results. The average number of decayed, missing, and filled teeth (DMFT) for both groups, control (CG) and CMT2, was considered low (CG = 2.46; CMT2 = 1.85, P=0.227). The OHIP-14 score was considered low (CG = 2.86, CMT2 = 5.83, P=0.899). The prevalence of self-reported TMD was 33.3% and 38.9% (P=0.718) in CG and CMT2 respectively and for self-reported bruxism was 4.8% (CG) and 22.2% (CMT2), without significant difference between groups (P=0.162). The most common clinical sign of TMD was masseter (CG = 38.1%; CMT2 = 66.7%) and temporalis (CG = 19.0%; GCMT2 = 33.3%) muscle pain. The geometric mean diameter (GMD) was not significantly different between groups (CG = 4369; CMT2 = 4627, P=0.157). Conclusion. We conclude that the CMT2 disease did not negatively have influence either on oral health status in the presence and severity of TMD and bruxism or on masticatory performance
Bioassay-Guided Evaluation of Antinociceptive Effect of N-Salicyloyltryptamine: A Behavioral and Electrophysiological Approach
We investigated the antinociceptive and nerve excitability effects of the N-salicyloyltryptamine (NST) NST-treated mice exhibited a significant decrease in the number of writhes when 100 and 200 mg/kg (i.p.) were administered (i.p.). This effect was not antagonized by naloxone (1.5 mg/kg, i.p.). NST inhibited the licking response of the injected paw when 100 and 200 mg/kg were administered (i.p.) to mice in the first and second phases of the formalin test. Because the antinociceptive effects could be associated with neuronal excitability inhibition, we performed the single sucrose gap technique and showed that NST (3.57 mM) significantly reduced (29.2%) amplitude of the compound action potential (CAP) suggesting a sodium channel effect induced by NST. Our results demonstrated an antinociceptive activity of the NST that could be, at least in part, associated to the reduction of the action potential amplitude. NST might represent an important tool for pain management
Passatempo Virus, a Vaccinia Virus Strain, Brazil
Passatempo virus was isolated during a zoonotic outbreak. Biologic features and molecular characterization of hemagglutinin, thymidine kinase, and vaccinia growth factor genes suggested a vaccinia virus infection, which strengthens the idea of the reemergence and circulation of vaccinia virus in Brazil. Molecular polymorphisms indicated that Passatempo virus is a different isolate
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