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Light sensing has been extensively characterized in the human pathogen Acinetobacter baumannii at environmental temperatures. However, the influence of light on the physiology and pathogenicity of human bacterial pathogens at temperatures found in warm-blooded hosts is still poorly understand. In this work, we show that Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa (ESKAPE) priority pathogens, which have been recognized by the WHO and the CDC as critical, can also sense and respond to light at temperatures found in human hosts. Most interestingly, in these pathogens, light modulates important pathogenicity determinants as well as virulence in an epithelial infection model, which could have implications in human infections. In fact, we found that alpha-toxin-dependent hemolysis, motility, and growth under iron-deprived conditions are modulated by light in S. aureus Light also regulates persistence, metabolism, and the ability to kill competitors in some of these microorganisms. Finally, light exerts a profound effect on the virulence of these pathogens in an epithelial infection model, although the response is not the same in the different species; virulence was enhanced by light in A. baumannii and S. aureus, while in A. nosocomialis and P. aeruginosa it was reduced. Neither the BlsA photoreceptor nor the type VI secretion system (T6SS) is involved in virulence modulation by light in A. baumannii Overall, this fundamental knowledge highlights the potential use of light to control pathogen virulence, either directly or by manipulating the light regulatory switch toward the lowest virulence/persistence configuration.IMPORTANCE Pathogenic bacteria are microorganisms capable of producing disease. Dangerous bacterial pathogens, such as Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii, are responsible for serious intrahospital and community infections in humans. Therapeutics is often complicated due to resistance to multiple antibiotics, rendering them ineffective. In this work, we show that these pathogens sense natural light and respond to it by modulating aspects related to their ability to cause disease; in the presence of light, some of them become more aggressive, while others show an opposite response. Overall, we provide new understanding on the behavior of these pathogens, which could contribute to the control of infections caused by them. Since the response is distributed in diverse pathogens, this notion could prove a general concept.

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Free-ranging grey wolves (Canis lupus), which are presently recolonizing Italy, can be parasitized by a diversity of helminths, but have rarely been subject to studies of their parasites. Therefore, this study aims to determine the prevalence of gastrointestinal helminths of road-killed grey wolves from the Piedmont region of Italy. Forty-two wolves were collected and examined for the presence of helminths. We recorded 12 helminth species: nine Nematoda and three Cestoda. The nematodes were: Ancylostoma caninum (7.1%), Capillaria sp. (2.4%), Molineus sp. (2.4%), Pterygodermatites affinis (11.9%), Physaloptera sibirica (9.5%), Toxocara canis (9.5%), Toxascaris leonina (2.4%) and Uncinaria stenocephala (26.2%); the cestodes were: Dipylidium caninum (4.8%), Mesocestoides sp. (4.8%) and Taenia multiceps (76.2%). Physaloptera sibirica had the highest mean intensity and T. multiceps had the highest prevalence. Based on age and sex, no differences in the intensity or prevalence of helminth species were found among the hosts. Molineus sp. was recorded for the first time in wolves from the Palearctic region; P. affinis and P. sibirica are respectively reported for the first time in wolves from Europe and Italy.

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Non-diabetic individuals use hormones like insulin to improve muscle strength and performance. However, as insulin also leads the liver and the adipose tissue to an anabolic state, the purpose of this study was to investigate the effects of insulin on liver metabolism in trained non-diabetic Swiss mice. The mice were divided into four groups: sedentary treated with saline (SS) or insulin (SI) and trained treated with saline (TS) or insulin (TI). Training was made in a vertical stair, at 90% of the maximum load, three times per week. Insulin (0.3 U/kg body weight) or saline were given intraperitoneally five times per week. After eight weeks, tissue and blood were collected and in situ liver perfusion with glycerol+lactate or alanine+glutamine (4 mM each) was carried out. The trained animals increased their muscle strength (+100%) and decreased body weight gain (-11%), subcutaneous fat (-42%), mesenteric fat (-45%), and peritoneal adipocyte size (-33%) compared with the sedentary groups. Insulin prevented the adipose effects of training (TI). The gastrocnemius muscle had greater density of muscle fibers (+60%) and less connective tissue in the trained groups. Liver glycogen was increased by insulin (SI +40% and TI +117%), as well as liver basal glucose release (TI +40%). Lactate and pyruvate release were reduced to a half by training. The greater gluconeogenesis from alanine+glutamine induced by training (TS +50%) was reversed by insulin (TI). Insulin administration had no additional effect on muscle strength and reversed some of the lipolytic and gluconeogenic effects of the resistance training. Therefore, insulin administration does not complement training in improving liver glucose metabolism.

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Non-diabetic individuals use hormones like insulin to improve muscle strength and performance. However, as insulin also leads the liver and the adipose tissue to an anabolic state, the purpose of this study was to investigate the effects of insulin on liver metabolism in trained non-diabetic Swiss mice. The mice were divided into four groups: sedentary treated with saline (SS) or insulin (SI) and trained treated with saline (TS) or insulin (TI). Training was made in a vertical stair, at 90% of the maximum load, three times per week. Insulin (0.3 U/kg body weight) or saline were given intraperitoneally five times per week. After eight weeks, tissue and blood were collected and in situ liver perfusion with glycerol+lactate or alanine+glutamine (4 mM each) was carried out. The trained animals increased their muscle strength (+100%) and decreased body weight gain (-11%), subcutaneous fat (-42%), mesenteric fat (-45%), and peritoneal adipocyte size (-33%) compared with the sedentary groups. Insulin prevented the adipose effects of training (TI). The gastrocnemius muscle had greater density of muscle fibers (+60%) and less connective tissue in the trained groups. Liver glycogen was increased by insulin (SI +40% and TI +117%), as well as liver basal glucose release (TI +40%). Lactate and pyruvate release were reduced to a half by training. The greater gluconeogenesis from alanine+glutamine induced by training (TS +50%) was reversed by insulin (TI). Insulin administration had no additional effect on muscle strength and reversed some of the lipolytic and gluconeogenic effects of the resistance training. Therefore, insulin administration does not complement training in improving liver glucose metabolism.

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Abstract Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.

Resumo O período crepuscular é um dos fatores que pode influenciar na atividade hematofágica dos mosquitos. Muitos desses insetos iniciam ou terminam suas atividades nesse período. O objetivo deste trabalho foi estudar os Culicidae que ocorrem no crepúsculo vespertino em uma área de Floresta Atlântica no oeste de Santa Catarina, sul do Brasil. Além disso, foi analisada a possível influência de fatores abióticos, bem como abundância e riqueza de espécies. Para melhor avaliar a influência do período crepuscular na composição das espécies e na abundância destas, o crepúsculo foi dividido em três períodos: pré-crepúsculo, crepúsculo e pós-crepúsculo. Ao final do estudo foram coletados 984 exemplares distribuídos em 12 gêneros e 23 espécies. Trichoprosopon pallidiventer (Lutz, 1905) (59,76%), Aedes crinifer (Theobald, 1903) (8,13%) e Ae. scapularis (Rondani, 1848) (5,89%) foram as espécies mais abundantes. A maior abundância e riqueza de espécies se deram na primavera. Dentre os três períodos estudados, o pré-crepúsculo apresentou a maior abundância de mosquitos, em contrapartida, o pós-crepúsculo apresentou a menor abundância. Os períodos pré-crepuscular e crepuscular apresentaram maior similaridade entre si com relação à composição das espécies. Relacionando os fatores abióticos e as três espécies mais abundantes, não foi observada correlação significativa nos dados avaliados nos sete e 15 dias anteriores às coletas. Entretanto, a temperatura apresentou uma correlação positiva para estas três espécies. A relação entre as espécies coletadas e a potencial transmissão de agentes etiológicos causadores de doenças foi comentada.

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Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.(AU)

O período crepuscular é um dos fatores que pode influenciar na atividade hematofágica dos mosquitos. Muitos desses insetos iniciam ou terminam suas atividades nesse período. O objetivo deste trabalho foi estudar os Culicidae que ocorrem no crepúsculo vespertino em uma área de Floresta Atlântica no oeste de Santa Catarina, sul do Brasil. Além disso, foi analisada a possível influência de fatores abióticos, bem como abundância e riqueza de espécies. Para melhor avaliar a influência do período crepuscular na composição das espécies e na abundância destas, o crepúsculo foi dividido em três períodos: pré-crepúsculo, crepúsculo e pós-crepúsculo. Ao final do estudo foram coletados 984 exemplares distribuídos em 12 gêneros e 23 espécies. Trichoprosopon pallidiventer (Lutz, 1905) (59,76%), Aedes crinifer (Theobald, 1903) (8,13%) e Ae. scapularis (Rondani, 1848) (5,89%) foram as espécies mais abundantes. A maior abundância e riqueza de espécies se deram na primavera. Dentre os três períodos estudados, o pré-crepúsculo apresentou a maior abundância de mosquitos, em contrapartida, o pós-crepúsculo apresentou a menor abundância. Os períodos pré-crepuscular e crepuscular apresentaram maior similaridade entre si com relação à composição das espécies. Relacionando os fatores abióticos e as três espécies mais abundantes, não foi observada correlação significativa nos dados avaliados nos sete e 15 dias anteriores às coletas. Entretanto, a temperatura apresentou uma correlação positiva para estas três espécies. A relação entre as espécies coletadas e a potencial transmissão de agentes etiológicos causadores de doenças foi comentada.(AU)

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Crepuscular period is one of the factors that may influence the biting activity of mosquitoes. Many of these insects have a peak activity in this period. The purpose of this study was to investigate the afternoon crepuscular activity of Culicidae in a remaining area of Atlantic Forest in western Santa Catarina, southern Brazil. Moreover, the possible influence of abiotic factors, the abundance and species richness were verified. In order to better analyze the influence of crepuscular period in specific composition and abundance of mosquitoes, the dusk was divided into three periods: pre-sunset, sunset and post-sunset. At the end of the study, nine hundred and eight four specimens distributed in 12 genera and 23 species were collected. Trichoprosopon pallidiventer (Lutz, 1905) (59.76%), Aedes crinifer (Theobald, 1903) (8.13%), Ae. scapularis (Rondani, 1848) (5.89%) were the most abundant species. Spring time presented the greatest abundance and species richness. During the study, among the three periods evaluated, pre-sunset had the greatest abundance and post-sunset the lowest. Pre-sunset and sunset had the greatest similarity between species. Regarding to the abiotic factors evaluated seven and 15 days before sampling, they did not present significant correlation for the three most abundant species. However, temperature had a positive correlation to these species. Moreover, the correlation between collected species and its possible role as vectors of etiological agents of diseases was discussed.

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Recently, the number of Aedes aegypti foci has increased in west of Santa Catarina, south Brazil, which has increased concern regarding mosquito-borne disease outbreaks such as dengue fever, Zika virus, and chikungunya. Therefore, it is important to monitor genetic resistance to insecticides through "knockdown resistance". Homozygosity (Ile/Ile) at position 1016 in the coding region of a voltage-dependent sodium channel gene (Nav) may induce resistance to pyrethroid insecticides. We evaluated the frequency of these alleles in A. aegypti in west Santa Catarina. In total, 349 specimens were obtained from the microregions of Joaçaba (31), Concórdia (35), Chapecó (154), and São Miguel do Oeste (129). We found that 109 individuals (31.0%) were homozygous for Val/Val, 102 (29.0%) were heterozygous for Val/Ile, and 138 (40.0%) were homozygous for Ile/Ile. The allele frequencies were similar for Val (0.455) and Ile (0.545). Joaçaba and Concórdia had the highest mutant allele frequencies (0.825 and 0.685, respectively). Therefore, these populations should be monitored for increases in pyrethroid resistance. The São Miguel do Oeste and Chapecó populations had similar frequencies of Val and Ile and were not in Hardy-Weinberg equilibrium, suggesting that a selection pressure or other evolutionary force has occurred. In conclusion, the observed frequency of Ile/Ile homozygous individuals in the region studied requires attention, because the implementation of controls using pyrethroid may increase the frequency of the mutant allele through the selection of resistant populations.

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During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25%). This is the first report of feather mites on Calidris fuscicollis in Brazil.

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Abstract During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25%). This is the first report of feather mites on Calidris fuscicollis in Brazil.

Resumo Durante o período de 2010-2012, oitenta espécimes de Calidris fuscicollis (Vieillot, 1819) foram coletados na costa sul do Estado do Rio Grande do Sul, com o objetivo de determinar a presença de ácaros de pena. Das 80 aves examinadas, 32,5% estavam infestadas por ácaros, os quais foram identificados como Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31,25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22,5%) e Alloptes limosae (Dubinin, 1951) (Alloptidae) (6,25%). Este é o primeiro relato de ácaros de pena em Calidris fuscicollis no Brasil.

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During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25%). This is the first report of feather mites on Calidris fuscicollis in Brazil.(AU)

Durante o período de 2010-2012, oitenta espécimes de Calidris fuscicollis (Vieillot, 1819) foram coletados na costa sul do Estado do Rio Grande do Sul, com o objetivo de determinar a presença de ácaros de pena. Das 80 aves examinadas, 32,5% estavam infestadas por ácaros, os quais foram identificados como Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31,25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22,5%) e Alloptes limosae (Dubinin, 1951) (Alloptidae) (6,25%). Este é o primeiro relato de ácaros de pena em Calidris fuscicollis no Brasil.(AU)

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The giant kidney worm Dioctophyme renale is normally found in wild carnivores and domestic dogs, with aquatic oligochaetes acting as intermediate hosts. In the present study a prevalence of 50% of third-stage larvae of D. renale was recorded in 60 specimens of the freshwater turtle Trachemys dorbigni from southern Brazil. Larvae were encysted in muscles, the coelomic cavity and mesentery, the serous lining of the stomach and on the surfaces of the lung, heart, liver, pancreas, spleen and intestines. There are no previous records of reptiles being part of the life cycle of D. renale, although fish and amphibians normally act as paratenic hosts. This is the first report of third-stage D. renale larvae in the freshwater turtle, T. dorbigni.

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A total of 81 Tyraniidae birds were examined, 80 Pitangus sulphuratus (Linnaeus, 1766) (Great kiscadee), and one Machetornis rixosa (Vieilot, 1819) (Cattle tyrant), for collection of nasal mites, which were identified as Ptilonyssus spinosus (Brooks & Strandtmann, 1960) and Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). This finding characterises the first report of P. spinosus and S. longisetosae in P. sulphuratus, and the first record of P. spinosus in M. rixosa, and expands the geographic distribution of these species. It is the first occurrence of S. longisetosae in the Neotropics, and the first citation of P. spinosus in the state of Rio Grande do Sul, Brazil.

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A total of 81 Tyraniidae birds were examined, 80 Pitangus sulphuratus (Linnaeus, 1766) (Great kiscadee), and one Machetornis rixosa (Vieilot, 1819) (Cattle tyrant), for collection of nasal mites, which were identified as Ptilonyssus spinosus (Brooks & Strandtmann, 1960) and Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). This finding characterises the first report of P. spinosus and S. longisetosae in P. sulphuratus, and the first record of P. spinosus in M. rixosa, and expands the geographic distribution of these species. It is the first occurrence of S. longisetosae in the Neotropics, and the first citation of P. spinosus in the state of Rio Grande do Sul, Brazil.

Foram examinadas 81 aves Tyraniidae, 80 Pitangus sulphuratus (Linnaeus, 1766) (Bem-te-vi) e um Machetornis rixosa (Vieilot, 1819) (Suiriri-cavaleiro) para coleta de ácaros nasais, os quais foram identificados como Ptilonyssus spinosus (Brooks & Strandtmann, 1960) e Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). Este achado caracteriza o primeiro relato de P. spinosus e S. longisetosae em P. sulphuratus e o primeiro registro de P. spinosus em M. rixosa, e amplia a distribuição geográfica destas espécies, sendo a primeira ocorrência de S. longisetosae na região neotropical e primeira citação de P. spinosus no Rio Grande do Sul, Brasil.

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A total of 81 Tyraniidae birds were examined, 80 Pitangus sulphuratus (Linnaeus, 1766) (Great kiscadee), and one Machetornis rixosa (Vieilot, 1819) (Cattle tyrant), for collection of nasal mites, which were identified as Ptilonyssus spinosus (Brooks & Strandtmann, 1960) and Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). This finding characterises the first report of P. spinosus and S. longisetosae in P. sulphuratus, and the first record of P. spinosus in M. rixosa, and expands the geographic distribution of these species. It is the first occurrence of S. longisetosae in the Neotropics, and the first citation of P. spinosus in the state of Rio Grande do Sul, Brazil.(AU)

Foram examinadas 81 aves Tyraniidae, 80 Pitangus sulphuratus (Linnaeus, 1766) (Bem-te-vi) e um Machetornis rixosa (Vieilot, 1819) (Suiriri-cavaleiro) para coleta de ácaros nasais, os quais foram identificados como Ptilonyssus spinosus (Brooks & Strandtmann, 1960) e Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). Este achado caracteriza o primeiro relato de P. spinosus e S. longisetosae em P. sulphuratus e o primeiro registro de P. spinosus em M. rixosa, e amplia a distribuição geográfica destas espécies, sendo a primeira ocorrência de S. longisetosae na região neotropical e primeira citação de P. spinosus no Rio Grande do Sul, Brasil.(AU)

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Sarcocystis neurona and Sarcocystis falcatula are very similar species of Apicomplexan protozoa that use marsupials of the genus Didelphis as definitive hosts. These mammals can serve as definitive hosts not only for these two parasites, but for other Sarcocystis such as Sarcocystis speeri and Sarcocystis lindsayi. Sarcocystis shed by opossums (with the exception of S. neurona) can cause disease in a great variety of birds, being commonly associated with acute pulmonary sarcocystosis in zoos. S. neurona is the most commonly associated parasite with the equine protozoal myeloencephalitis in horses. Herein we assessed the variability of Sarcocystis spp. isolated from opossums of the state of Rio Grande do Sul, Brazil, by sequencing fragments of genes coding for glycosylphosphatidylinositol-anchored surface antigens (termed surface antigen or SAG), SAG2, SAG3 and SAG4. Two genetic groups were identified, one of them related to S. falcatula and the other related to S. neurona. Various allelic combinations of SAG2, SAG3 and SAG4 occur among S. falcatula related isolates and strong evidences suggest that such isolates may exchange high divergent alleles in possible sexual recombination processes. Regarding the group S. neurona-like (isolates G37 and G38), none of the individuals in this group share alleles with individuals of the other group. Comparing G37 and G38 strains and North American strains of S. neurona, four polymorphisms were identified at SAG-3, five at SAG-2 and three at SAG-4. Gene sequences of locus SAG-3 from isolates G37 and G38 differed from the other sequences by an insertion 81bp long. This insertion contains several dinucleotide repeats of AT, resembling a microsatellite locus and has already been detected in SAG3 sequences of S. neurona from North America. When aligned against North American strains of S. neurona, G37 and G38 isolates have a deletion of 8 nucleotides within this intron which indicate that S. neurona strains of South America are divergent from that of North America. From the results obtained so far, we have shown extensive variability in surface antigens coding sequences among Sarcocystis eliminated by mammals of the genus Didelphis spp. In addition, such divergent alleles may be exchanged in possible sexual recombination processes between different isolates of S. falcatula related isolate. The evolutionary relationships within S. falcatula related isolates will be best clarified after markers less subjected to selection pressures are analyzed in conjunction with surface antigen genes. These results may have a striking impact on the knowledge of the Sarcocystis species that infect opossums in Brazil and also in the epidemiology of the infections caused by these protozoans.

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