Endoparasites in a wild boar population (Sus scrofa) from Bahía Samborombón, Buenos Aires, Argentina

En Argentina se sabe poco sobre la parasitofauna en cerdos silvestres. Aquí, se describe por primera vez la comunidad parasitaria de una población silvestre de Sus scrofa en el área protegida Bahía Samborombón. Se tomaron muestras de materia fecal y se revisaron las vísceras de 30 individuos. La prevalencia (P) total fue de 90%, registrándose Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%) y Trichuris sp. (P = 4%) (Nematoda) en el análisis coprológico y M. hirudinaceus (P = 33%) y A. suum (P = 23%); O. dentatum (P = 3%) y quistes hidatídicos de Echinococcus sp. (P = 20%) (Cestoda, Taeniidae) en la prospección helmintológica. Los valores de asociación del índice de Fager fueron no significativos con excepción del par Isospora sp.-Eimeria sp. El presente estudio muestra que la población de cerdos silvestres de Bahía Samborombón presenta una alta riqueza de especies parásitas, muchas de las cuales revisten importancia zoonótica como Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp. y Echinococcus sp.In Argentina little is known about the parasitofauna in wild pigs. This work discloses parasitic species in a wild population of Sus scrofa in the Bahía Samborombón protected area. Fecal samples were taken from 30 individuals and their viscera were prospected. The total prevalence (P) was 90%, with a specific richness of 11. In the coprological analysis were detected: Eimeria sp. (P = 18.5%), Isospora sp. (P = 22%) (Coccidia), Iodamoeba sp. (P = 52%) (Amoebidae), Macracanthorhynchus hirudinaceus (P = 33%) (Acanthocephala), Ascaris suum (P = 22%), Oesophagostomum dentatum (P = 4%), Globocephalus sp. (P = 7.5%), Metastrongylus sp. (P = 7.5%), Hyostrongylus sp. (P = 18.5%), and Trichuris sp. (P = 4%) (Nematoda). In the helminthological prospections were observed juveniles and adults of M. hirudinaceus (P = 33%) and A. suum (P = 23%); O. dentatum (P = 3%) and hydatid cysts of Echinococcus sp. (P = 20%) (Cestoda, Taeniidae). The association values of the Fager index were not significant except for the pair Isospora sp.-Eimeria sp. The present study shows that the population of wild pigs of Samborombón Bay presents a high richness of parasitic species, many of which have zoonotic importance such as Eimeria sp., Isospora sp., Macracanthorhynchus sp., Ascaris sp., and Echinococcus sp.Facultad de Ciencias Naturales y Muse

FIRST INSIGHTS INTO THE MIGRATION PATTERN OF AN UPLAND GOOSE (CHLOEPHAGA PICTA) BASED ON SATELLITE TRACKING

Detailed knowledge of the migratory strategies is important to understand the ecology and evolution of migration and the conservation of migratory birds The Argentinean federal government declared sheldgeese (Chloephaga spp.) pests in 1930, claiming that they reduce crop yield. Currently sheldgeese have suffered severe reductions in their populations and are the focus of serious conservation concern. From September to April they breed in southern Patagonia (Argentina and Chile) while from May to September they winter mainly in the southern Pampas (central east Argentina). The precise knowledge of their migratory routes is essential to ensure protection of necessary resources and sites needed on their annual journeys. Here, by using a satellite transmitter for the first time we unravel the migration route of an Upland Goose (Chloephaga picta), a species endemic to southern South America with an unknown migration strategy. We received data for 121 days (from September 2014 to January 2015). During this time, the bird migrated 1485 km from the wintering grounds in Buenos Aires Province to the breeding area in Santa Cruz province, Patagonia. Part of the migration route was over the sea. The largest displacement was 817 km in 19 hours, representing a minimum mean speed of 43 km h-1

Migration routes and non-breeding areas of Common Terns (Sterna hirundo) from the Azores

We describe the migration routes and non-breeding areas of Common Terns (Sterna hirundo) from the Azores Archipelago, based on ringing (banding) recoveries and tracking of three birds using geolocators. Over 20 years, there have been 55 transatlantic recoveries of Common Terns from the Azores population: six from Argentina and 49 from Brazil. The three tracked birds migrated south in different months (August, September, November), but the northern migration was more synchronous, with all leaving in April. The birds were tracked to three areas of the South American coast: the male spent November–April on the northern Brazilian coast (13°N–2°S), whereas the two females first spent some time off central-eastern Brazil (4–16°S; one for 1 week, the other for 3 months) and then moved south to the coast of south-eastern Brazil, Uruguay and northern Argentina (24–39°S). Although caution is needed given the small sample size and errors associated with geolocation, the three tracked terns potentially travelled a total of ~23 200 km to and returning from their non-breeding areas, representing an average movement of ~500 km day–1. With the exception of Belém, in northern Brazil, and Lagoa do Peixe, in southern Brazil, the coastal areas used by the tracked birds were also those with concentrations of ringing recoveries, confirming their importance as non-breeding areas for birds from the Azores

Surveillance of avian malaria and related haemoparasites in common terns (Sterna hirundo) on the Atlantic coast of South America

Haemosporidia (Apicomplexa, Haemosporida) are protozoa that infect vertebrate blood cells and are transmitted by vectors. Among vertebrates, birds possess the greatest diversity of haemosporidia, historically placed in 3 genera: Haemoproteus, Leucocytozoon and Plasmodium, the causative agent of avian malaria. In South America, existing data on haemosporidia are spatially and temporally dispersed, so increased surveillance is needed to improve the determination and diagnosis of these parasites. During the non-breeding season in 2020 and 2021, 60 common terns (Sterna hirundo) were captured and bled as part of ongoing research on the population health of migratory birds on the Argentinian Atlantic coast. Blood samples and blood smears were obtained. Fifty-eight samples were screened for Plasmodium, Haemoproteus and Leucocytozoon, as well as for Babesia parasites by nested polymerase chain reaction and by microscopic examination of smears. Two positive samples for Plasmodium were found. The cytochrome b lineages detected in the present study are found for the first time, and are close to Plasmodium lineages found in other bird orders. The low prevalence (3.6%) of haemoparasites found in this research was similar to those reported for previous studies on seabirds, including Charadriiformes. Our findings provide new information about the distribution and prevalence of haemosporidian parasites from charadriiforms in the southernmost part of South America, which remains understudied

Sonic hedgehog inhibition reduces in vitro tumorigenesis and alters expression of GLI1-target genes in a desmoplastic medulloblastoma cell line

Medulloblastoma is one of the most frequent and aggressive tumors of childhood. The Sonic hedgehog (Shh) pathway, related to human development, is altered in most medulloblastomas: genes like Ptch, Smo, or Sufu suffer mutations in 15% to 25% of these tumors. We tested Shh inhibition in the Daoy medulloblastoma cell line by two methods: a molecular one, direct Gli1 siRNA inhibition; and a pharmacological inhibition of Smo, upstream of Gli1, by cyclopamine. Afterwards, a comparison of cellular and molecular responses was done. In general, we proved that cell viability, cell migration and cell colony formation decreased after Shh inhibition, which might confer a less tumorigenic status to Daoy cells. Moreover, we assessed the expression of different Gli1 target genes and other genes and found that Shh shows a crosstalk with oncogenes and tumor suppressor genes that have been described in numerous tumors. All these experiments give an overview of the Shh pathway in medulloblastoma, together with the demonstration of the efficacy of cyclopamine and Gli1 siRNA Shh inhibition in vitro

Novel insights into the genomic basis of citrus canker based on the genome sequences of two strains of Xanthomonas fuscans subsp. aurantifolii

Background: Citrus canker is a disease that has severe economic impact on the citrus industry worldwide. There are three types of canker, called A, B, and C. The three types have different phenotypes and affect different citrus species. The causative agent for type A is Xanthomonas citri subsp. citri, whose genome sequence was made available in 2002. Xanthomonas fuscans subsp. aurantifolii strain B causes canker B and Xanthomonas fuscans subsp. aurantifolii strain C causes canker C. Results: We have sequenced the genomes of strains B and C to draft status. We have compared their genomic content to X. citri subsp. citri and to other Xanthomonas genomes, with special emphasis on type III secreted effector repertoires. In addition to pthA, already known to be present in all three citrus canker strains, two additional effector genes, xopE3 and xopAI, are also present in all three strains and are both located on the same putative genomic island. These two effector genes, along with one other effector-like gene in the same region, are thus good candidates for being pathogenicity factors on citrus. Numerous gene content differences also exist between the three cankers strains, which can be correlated with their different virulence and host range. Particular attention was placed on the analysis of genes involved in biofilm formation and quorum sensing, type IV secretion, flagellum synthesis and motility, lipopolysacharide synthesis, and on the gene xacPNP, which codes for a natriuretic protein. Conclusion: We have uncovered numerous commonalities and differences in gene content between the genomes of the pathogenic agents causing citrus canker A, B, and C and other Xanthomonas genomes. Molecular genetics can now be employed to determine the role of these genes in plant-microbe interactions. The gained knowledge will be instrumental for improving citrus canker control.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientIfico e Tecnologico (CNPq)Coordenacao para Aperfeicoamento de Pessoal de Ensino Superior (CAPES)Fundo de Defesa da Citricultura (FUNDECITRUS

Multiple Nuclear Gene Phylogenetic Analysis of the Evolution of Dioecy and Sex Chromosomes in the Genus Silene

In the plant genus Silene, separate sexes and sex chromosomes are believed to have evolved twice. Silene species that are wholly or largely hermaphroditic are assumed to represent the ancestral state from which dioecy evolved. This assumption is important for choice of outgroup species for inferring the genetic and chromosomal changes involved in the evolution of dioecy, but is mainly based on data from a single locus (ITS). To establish the order of events more clearly, and inform outgroup choice, we therefore carried out (i) multi-nuclear-gene phylogenetic analyses of 14 Silene species (including 7 hermaphrodite or gynodioecious species), representing species from both Silene clades with dioecious members, plus a more distantly related outgroup, and (ii) a BayesTraits character analysis of the evolution of dioecy. We confirm two origins of dioecy within this genus in agreement with recent work on comparing sex chromosomes from both clades with dioecious species. We conclude that sex chromosomes evolved after the origin of Silene and within a clade that includes only S. latifolia and its closest relatives. We estimate that sex chromosomes emerged soon after the split with the ancestor of S. viscosa, the probable closest non-dioecious S. latifolia relative among the species included in our study

Characterization of cellular and molecular responses of human glioblastoma to Transforming Growth Factor-β signalling pathway inhibition

Glioblastoma Multiforme (GBM) is the most prevalent malignant brain tumour accounting for 60-70% of all gliomas. Improvements in survival over the past 100 years can be measured only in weeks, and current achieved median survival ranges only 12-15 months. A hallmark of this malignancy is the intrinsic resistance to current therapies. Numerous efforts using molecularly targeted therapeutics have not significantly changed the near uniform lethality of this disease. The TGF-β signalling pathway plays a key role in GBM. It is implicated in progression, infiltration, and chemo/radioresistance as well as in the maintenance of stem-like phenotype of GBM CSC. Several inhibitors of different elements and regulators of the TGF-β pathway have entered to clinical trials. Among them, P17 and P144 inhibitory peptides of the TGF-β pathway have been tested for the treatment of different diseases including tumours. We decided to analyse the therapeutic potential of P144 for the treatment of GBM. We found that P144 impaired in vitro cellular processes as proliferation, migration, invasiveness and tumorigenicity. Apoptosis and anoikis were significantly increased by P144. Additionally, P144 blocked the TGF-β protective effect against apoptosis. The inhibition of TGF-β signalling by P144 affected the self-renewal capacity of a putative CSC subpopulation in vitro. These results were confirmed by the analysis on Brain Tumour Initiating Cells (BTIC) isolated from human GBM biopsies. P144 decreased in vitro proliferation, migration, and self-renewal capacity of this subpopulation. The effect of P144 was impaired by hypoxia. However, the precise underlying mechanism of hypoxia on P144 must be elucidated. We confirm the inhibition of TGF-β signalling by P144 through SMAD2 phosphorylation blockade, the pivotal initiation event of the pathway, which was translated to a reduction of P-SMAD2 nuclear translocation. Both results suggested an in vitro regulation on the transcriptional target genes of the TGF-β pathway in GBM cell lines. Furthermore, we confirmed in vitro and in vivo, the upregulation of SMAD7 and the downregulation of SKI by P144 at transcriptional and translational levels. This observation strongly suggests the implication of these factors in the molecular mechanism triggered by P144. The therapeutic potential of P144 was analysed in a mouse subcutaneous tumour model. Despite that P144 impaired tumour growth and leaded to an increase in survival, negative contradictory results were obtained in the in vivo intracranial model. We can conclude that the therapeutic potential of P144 as a treatment of GBM is clear. However, previous to potential clinical development, further studies are required in order to confirm P144 effect over GBM in the brain environment, as well as to explore P144 therapeutic potential in combination with current (TMZ and/or radiation) and emerging molecular based therapies