34 research outputs found
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
Food handling in the domestic environment: an online questionnaire study with respondents from 24 of 26 Brazilian states
Este estudo teve como objetivo avaliar o perfil das práticas de manipulação de alimentos no ambiente domiciliar no Brasil utilizando um questionário online. Um questionário contendo perguntas sobre comportamento doméstico em nível de higiene e manipulação de alimentos foi construído e disponibilizado por redes sociais. O questionário continha informações sobre o perfil dos participantes, suas práticas de pré preparo, preparo e pós-preparo de alimentos e a ocorrência de doenças transmitidas por alimentos (DTA). Obteve-se 701 respostas, os entrevistados foram 78,31% do sexo feminino e 21,68% do sexo masculino, com média de idade de 31,2 anos. A maioria (94,3%) possuia ensino superior completo ou incompleto. Na etapa de pré-preparo, os participantes avaliam o prazo de validade (97,28%) e a temperatura de armazenamento (44,79%) dos produtos no momento da compra. Em relação às práticas de manipulação dos alimentos, apenas alguns participantes lavavam as embalagens dos alimentos antes de armazená-los (31,95%) ou retiravam adornos ao lavar os alimentos (61,48%). A maioria dos participantes lavam as mãos (91,58%) e os vegetais (99,28%); entretanto, um grupo de entrevistados relatou lavar carne crua (27,81%) antes de prepará-la. Superfícies de corte como tábuas de plástico (50,36%) e de vidro (49,36%) foram os mais prevalentes no estudo. A maioria dos entrevistados não sabe há quanto tempo usa as tábuas de corte (67,62%) e utilizam a mesma superfície para manusear produtos crus e prontos para o consumo (84,17%). Quanto ao preparo, a maioria dos entrevistados declarou não verificar a temperatura dos alimentos durante o preparo (86,31%), ignorando a temperatura ideal de cozimento (88,26%). Em relação à ocorrência de DVA, 79,17% dos entrevistados relataram que já apresentaram sinais clínicos suspeitos associados a alimentos contaminados e 65,59% não procuraram atendimento médico. Nesse sentido, os participantes demonstraram desconhecimento sobre as práticas adequadas para a segurança dos alimentos no ambiente domiciliar, evidenciando a necessidade de realização de programas de educação em saúde com a população brasileira.Using an online questionnaire, this study evaluated the profile of a Brazilian population’s food handling practices in the home environment. The questionnaire, containing questions about domestic behavior in terms of hygiene and food handling, was built and available through social media sites. Information about the participants’ profiles, their food pre-preparation, food preparation, and food post-preparation practices, and the occurrence of foodborne diseases (FBDs) was included in the questionnaire. A total of 701 responses were obtained. The interviewees included 78.31% female participants and 21.68% male participants, with an average age of 31.2 years. Nearly all (94.3%) had a complete or incomplete higher education. In the pre preparation stage, the participants evaluated the shelf life (97.28%) and storage temperature (44.79%) of the products while purchasing them. Regarding food handling practices, only a few participants washed the food packages before storing them (31.95%) or removed hand jewelry or other adornments when washing food (61.48%). Most participants washed their hands (91.58%) and washed vegetables (99.28%). But a group of interviewees reported washing raw meat (27.81%) before preparing it. Cutting surfaces such as plastic (50.36%) and glass (49.36%) tops were the most prevalent in the study. Most respondents did not know how long they had been using their cutting boards (67.62%) and mentioned using the same surface to handle both raw and ready-to-eat products (84.17%). As for the preparation, most interviewees declared they did not check the food temperature during preparation (86.31%), ignoring the ideal cooking temperature (88.26%). Regarding the occurrence of FBDs, 79.17% of the interviewees reported having suspicious clinical signs associated with contaminated foods and 65.59% did not seek medical help. Thus, the participants demonstrated ignorance about adequate practices for food safety in the home environment, highlighting the need to conduct health education programs within the Brazilian population
Embriogênese somática e regeneração in vitro de clones elite de Theobroma cacao
The objective of this work was to evaluated a procedure for somatic embryogenesis and regeneration of cacao (Theobroma cacao L.) elite clones. Petal explants from cacao clones TSH 565 and TSH 1188 were cultured on PCG and SCG-2 media, for calli growth. Somatic embryos were formed on the surface of embryogenic calli after transfer to embryo development (ED) medium. Clone TSH 565 showed a higher embryogenic potential than TSH 1188. The best combination of carbon source for embryo induction in ED medium was genotype-specifi c. Embryogenic callus formations increased in micropore tape-sealed Petri dishes, irrespective of cacao genotype. Mature somatic embryos were successfully converted into plantlets.O objetivo deste trabalho foi avaliar um procedimento para embriogênese somática e regeneração de clones elite de cacau. Pétalas dos clones de cacau TSH 565 e TSH 1188 foram cultivadas em meios PCG e SCG-2para o crescimento de calos. Embriões somáticos desenvolveram-se na superfície dos calos embriogênicos, após a transferência para o meio ED. O clone TSH 565 apresentou maior potencial embriogênico do que oTSH 1188. A melhor combinação de fonte de carbono quanto à indução de embriões em meio ED foi específi ca do genótipo. A formação de calos embriogênicos foi superior em placas de Petri seladas com fi ta hipoalergênica,independentemente do genótipo. Embriões maduros de ambos os genótipos foram convertidos em plântulas
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
El Eco de Santiago : diario independiente: Año VI Número 1918 - 1901 Agosto 05
Raman scattering from polaritons was studied near resonance in ZnSe. Detailed dispersion curves were determined experimentally for different incident frequencies and compared with theoretical results. Measurements of linewidth and relative scattered intensities were also performed. The observed polariton dispersion curves showed a deviation from theory near the same frequencies for which line broadening occurred, indicating the necessity of including relaxation effects depending on polariton frequency. Structure in the polariton intensity as a function of frequency, not observed before, may also be related to damping
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
Congenital toxoplasmosis in humans: an update of worldwide rate of congenital infections
International audienceAbstrac
All about neosporosis in Brazil
Abstract Neospora caninum is protozoan parasite with domestic and wild dogs, coyotes and grey wolves as the definitive hosts and many warm-blooded animals as intermediate hosts. It was cultivated and named in 1988. Neosporosis is a major disease of cattle and has no public health significance. Since 1990’s N. caninum has emerged as a major cause of abortion in cattle worldwide, including in Brazil. N. caninum also causes clinical infections in several other animal species. Considerable progress has been made in understanding the biology of N. caninum and there are more than 200 papers on this subject from Brazil. However, most of the reports on neosporosis from Brazil are serological surveys. Overall, little is known of clinical neosporosis in Brazil, particularly cattle. The few reports pertain to sporadic cases of abortion with no information on epidemics or storms of abortion. The objective of the present review is to summarize all reports from Brazil and suggest topic for further research, including prevalence of N. caninum oocysts in soil or in canine feces, and determining if there are additional definitive hosts, other than the domestic dog. There is need for a national survey in cattle using defined parameters. Future researches should focus on molecular characterization of N. caninum strains, possibility of vaccine production and relationship between wildlife and livestock epidemiology