Sarcocystis cymruensis: discovery in Western Hemisphere in the Brown rat (Rattus norvegicus) from Grenada, West Indies: redescription, molecular characterization, and transmission to IFN-γ gene knockout mice via sporocysts from experimentally infected domestic cat (Felis catus)

Rodents are intermediate hosts for many species of Sarcocystis. Little is known of Sarcocystis cymruensis that uses the Brown rat (Rattus norvegicus) as intermediate hosts and the domestic cat (Felis catus) as experimental definitive host. Here, we identified and described Sarcocystis cymruensis in naturally infected R. norvegicus from Grenada, West Indies. Rats (n = 167) were trapped in various locations in two parishes (St. George and St. David). Microscopic, thin (\u3c 1 μm) walled, slender sarcocysts were found in 11 of 156 (7.0%) rats skeletal muscles by squash examination. A laboratory-raised cat fed naturally infected rat tissues excreted sporocysts that were infectious for interferon gamma gene knockout (KO) mice, but not to Swiss Webster outbred albino mice. All inoculated mice remained asymptomatic, and microscopic S. cymruensis-like sarcocysts were found in the muscles of KO mice euthanized on day 70, 116, and 189 post inoculation (p.i.). Sarcocysts from infected KO mice were infective for cats at day 116 but not at 70 days p.i. By transmission electron microscopy, the sarcocyst wall was Btype 1a.^ Detailed morphological description of the cyst wall, metrocytes, and bradyzoites is given for the first time. Additionally, molecular data on S. cymruensis are presented also for the first time. Molecular characterization of sarcocysts 18S rDNA and 28S rDNA, ITS-1, and cox1 loci showed the highest similarity with S. rodentifelis and S. muris. In conclusion, the present study described the natural infection of S. cymruensis in Brown rat for the first time in a Caribbean country and provided its molecular characteristics

Histopathological, morphological, and molecular characterization of Sarcocystis species in elk (Cervus elaphus) from Pennsylvania, USA

Sarcocystis sarcocysts are common in many species of domestic and wild animals. Here, we report sarcocystosis in muscles from 91 free range elk (Cervus elaphus) from Pennsylvania, USA, tested by histopathology, transmission electron microscopy (TEM), and DNA sequencing. Sarcocysts were detected in hematoxylin and eosin (HE)-stained sections from 83 of 91 (91.2%) elk, including 83/91 (91.2%) tongues and 15/17 (88.2%) hearts. With respect to age, sarcocysts were found in 0/5 calves, 8/9 (88.8%) yearlings, and 75/77 (97.4%) adults. Sarcocysts were identified in 62/69 (89.4%) females and 21/22 (91.2%) males. Associated lesions were mild and consisted of inflammatory foci around degenerate sarcocysts. There were two morphologically distinct sarcocysts based on wall thickness, thin (\u3c 0.5 μm) and thick-walled (\u3e 4.0 μm). Thin-walled sarcocysts had a TEM Btype 2^ and villar protrusions (vps), identical to Sarcocystis wapiti previously described from elk in western USA. This species was present both in tongue and heart samples and was detected in all infected elk. Thick-walled sarcocysts consisted of three morphologic variants, referred to herein as subkinds A, B, C. Subkind A sarcocysts were rare; only four sarcocysts were found in three elk. Histologically, they had a 5–8-μm thick wall with tufted vp. By TEM, the sarcocyst wall was Btype 12^ and appeared similar to Sarcocystis sybillensis, previously described from elk in USA. Subkind B, Sarcocystis sp.1 sarcocysts were also rare, found in only 1 elk. These sarcocysts had 6.7–7.3-μm-thick wall with TEM Btype 15b^ vp. Subkind C Sarcocystis sp.2 sarcocysts were more common (22/91). Morphologically, the sarcocyst wall was 6.1–6.8 μm thick and contained Btype 10b^ vp. Comparisons of ribosomal DNA loci with published sequences indicated all sarcocysts were similar to what has previously been isolated from cervid hosts across the northern hemisphere. Phylogenetic analysis placed the thin-walled S. wapiti within a strongly supported clade with S. linearis and S. taeniata, while the thick-walled cysts were very closely related to S. truncata, S. elongata, S. silva, and S. tarandi. Further sequencing is needed to produce molecular diagnostics to distinguish among these species. North American elk are hosts to multiple Sarcocystis species with diverse morphology, deriving from two separate evolutionary lineages

Sarcocystis cymruensis: discovery in Western Hemisphere in the Brown rat (Rattus norvegicus) from Grenada, West Indies: redescription, molecular characterization, and transmission to IFN-γ gene knockout mice via sporocysts from experimentally infected domestic cat (Felis catus)

Rodents are intermediate hosts for many species of Sarcocystis. Little is known of Sarcocystis cymruensis that uses the Brown rat (Rattus norvegicus) as intermediate hosts and the domestic cat (Felis catus) as experimental definitive host. Here, we identified and described Sarcocystis cymruensis in naturally infected R. norvegicus from Grenada, West Indies. Rats (n = 167) were trapped in various locations in two parishes (St. George and St. David). Microscopic, thin (\u3c 1 μm) walled, slender sarcocysts were found in 11 of 156 (7.0%) rats skeletal muscles by squash examination. A laboratory-raised cat fed naturally infected rat tissues excreted sporocysts that were infectious for interferon gamma gene knockout (KO) mice, but not to Swiss Webster outbred albino mice. All inoculated mice remained asymptomatic, and microscopic S. cymruensis-like sarcocysts were found in the muscles of KO mice euthanized on day 70, 116, and 189 post inoculation (p.i.). Sarcocysts from infected KO mice were infective for cats at day 116 but not at 70 days p.i. By transmission electron microscopy, the sarcocyst wall was Btype 1a.^ Detailed morphological description of the cyst wall, metrocytes, and bradyzoites is given for the first time. Additionally, molecular data on S. cymruensis are presented also for the first time. Molecular characterization of sarcocysts 18S rDNA and 28S rDNA, ITS-1, and cox1 loci showed the highest similarity with S. rodentifelis and S. muris. In conclusion, the present study described the natural infection of S. cymruensis in Brown rat for the first time in a Caribbean country and provided its molecular characteristics

Epidemiological and Public Health Significance of Toxoplasma gondii Infection in Wild Rabbits and Hares: 2010–2020

Toxoplasmosis is a zoonosis of global distribution, and Toxoplasma gondii infections are common in humans and animals worldwide. Hares and rabbits are important small game species, and their meat is consumed by humans in many countries. Demand for rabbit meat for human consumption is increasing; therefore, toxoplasmosis in rabbits and hares is of epidemiological significance. Viable T. gondii has been isolated from rabbits. The present review summarizes worldwide information on the seroprevalence, parasitological investigations, clinical cases, isolation, and genetic diversity of T. gondii in wild rabbits, free domestic rabbits, hares, and other rabbits from 2010 to 2020. Differences in prevalence, susceptibility, genetic variants, and clinical implications of T. gondii infection in rabbits and hares are discussed. This review will be of interest to biologists, parasitologists, veterinarians, and public health workers. Additional studies are needed to increase our knowledge of genetic variants and the population structure of T. gondii in rabbits and hares and to understand the differences in susceptibility to T. gondii in hares in different areas

Infrastructure for the development of context aware applications in pervasive environments.

O desenvolvimento tecnológico tem proporcionado que os computadores se tornem cada vez mais compactos e mais poderosos, levando a computação a um novo paradigma: o de Computação Pervasiva. Neste paradigma, os computadores estão embutidos em objetos comuns ao cotidiano das pessoas (e.g.,roupas, telefones, automóveis, canetas, óculos e eletrodomésticos em geral), permitindo-os estar acessíveis em qualquer lugar e a qualquer momento, integrando-se à vida das pessoas, agindo em benefício delas. Tornar estes dispositivos integrados aos seres humanos, requer que as aplicações se adaptem em tempo de execução às alterações no ambiente e às necessidades dos usuários. Isto exige que o desenvolvedor de aplicações voltadas a ambientes pervasivos lide com questões que fogem à lógica de negócio de sua aplicação, principalmente no que diz respeito à obtenção de contexto,que é fundamental para obtenção desta adaptabilidade desejada. Neste trabalho, aborda-se a problemática supra mencionada, propondo-se uma infraestrutura capaz de fornecer mecanismos para a obtenção, representação e inferência sobre a informação contextual, tornando-as disponíveis a qualquer aplicação que possa fazer uso delas. Mais especificamente, esta infra-estrutura denominada Lotus, contempla em uma abordagem integrada todos os aspectos relacionados com a provisão de informação contextual. A viabilidade da infra-estrutura foi demonstrada por meio do desenvolvimento de duas aplicações, uma no domínio de comunidades virtuais móveis e outra no domínio de ambientes pervasivos, onde foi possível constatar que a Lotus torna a informação contextual disponível para as aplicações, permitindo que o desenvolvedor foque na lógica de negócio da aplicação.Enabling applications to use any contextual information available in pervasive environment is a hard task from the perspective of the developers. In this work is described an approach to make that an easier task: The Lotus, which consists of an infra-structure for developing context-aware applications, providing mechanisms for acquiring, modeling, and delivering contextual information, enabling it to be shared by different applications. The feasibility of this infra-structure was established through development of a case study where was possible verify that Lotus made the contextual information available to the applications, enabling the developer to focuses on application business logi