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1.
Parasite ; 31: 22, 2024.
Article in English | MEDLINE | ID: mdl-38602374

ABSTRACT

In the present study, we examined 30 individuals of introduced African cichlids, Oreochromis niloticus and Coptodon rendalli, collected in a river spring of the Pardo River, Paranapanema River basin, southeastern Brazil. Based on morphological and molecular analyses of the partial LSU rDNA gene, we identified four species of monogeneans, Cichlidogyrus tilapiae, C. thurstonae, C. mbirizei, and Scutogyrus longicornis on the gills of O. niloticus, whereas individuals of C. rendalli were infested only with C. papernastrema. This is the first record of C. mbirizei and C. papernastrema in tilapias from Brazil. The ecological consequences of the introduction of exotic species of tilapia such as O. niloticus and C. rendalli along with their monogenean parasites in a wild environment represented by a river spring are discussed. Our new molecular data on Cichlidogyrus and Scutogyrus contribute to the investigation of the phylogenetic interrelationships of these widely distributed genera of monogeneans since their species composition is still unsettled.


Title: Parasites (Monogenea) des tilapias Oreochromis niloticus et Coptodon rendalli (Cichlidae) dans une source au Brésil. Abstract: Dans la présente étude, nous avons examiné 30 individus de cichlidés africains introduits, Oreochromis niloticus et Coptodon rendalli, collectés dans une source fluviale du fleuve Pardo, bassin du fleuve Paranapanema, dans le sud-est du Brésil. Sur la base d'analyses morphologiques et moléculaires du gène partiel de l'ADNr LSU, nous avons identifié quatre espèces de monogènes, Cichlidogyrus tilapiae, C. thurstonae, C. mbirizei et Scutogyrus longicornis sur les branchies d'O. niloticus, alors que les individus de C. rendalli étaient infestés uniquement par C. papernastrema. Il s'agit du premier signalement de C. mbirizei et C. papernastrema chez des tilapias du Brésil. Les conséquences écologiques de l'introduction d'espèces exotiques de tilapia telles que O. niloticus et C. rendalli ainsi que leurs monogènes parasites dans un environnement sauvage représenté par une source fluviale sont discutées. Nos nouvelles données moléculaires sur Cichlidogyrus et Scutogyrus contribuent à l'étude des interrelations phylogénétiques de ces genres de monogènes largement distribués puisque leur composition spécifique est encore incertaine.


Subject(s)
Cichlids , Fish Diseases , Parasites , Tilapia , Trematoda , Humans , Animals , Tilapia/parasitology , Cichlids/parasitology , Rivers , Phylogeny , Brazil/epidemiology , Gills/parasitology , Fish Diseases/epidemiology , Fish Diseases/parasitology
2.
Syst Parasitol ; 100(5): 521-530, 2023 10.
Article in English | MEDLINE | ID: mdl-37338662

ABSTRACT

The dactylogyrid genus Rhinoxenus (Monogenea: Dactylogyridae) is composed of specialized monogeneans infecting the nasal cavities of freshwater fishes from the Neotropical region. This taxon currently comprises 11 species and is easily distinguished from other monogeneans by the absence of the dorsal bar, ventral anchor with inconspicuous roots covered by a sclerotized cap, dorsal anchor greatly modified into a needle-like shape, and hook pair 2 located into bilateral lobes of the trunk. Specimens of Rhinoxenus euryxenus and Rhinoxenus paranaensis were found infecting the nasal cavities of Serrasalmus marginatus and Serrasalmus maculatus, respectively, from the Paraná River basin in Brazil. For the first time, molecular data of Rhinoxenus spp. were obtained and used as a basis for phylogenetic analyses of the genus. Furthermore, our findings represent the first record of R. paranaensis in Brazil.


Subject(s)
Characiformes , Fish Diseases , Trematoda , Animals , Phylogeny , Brazil , Nasal Cavity , Species Specificity , Rivers , Gills
3.
Parasite ; 28: 69, 2021.
Article in English | MEDLINE | ID: mdl-34643505

ABSTRACT

Diversity of Creptotrema was investigated using morphological and molecular tools, including data for Creptotrema creptotrema (type-species). Three new species, parasites of Brazilian fishes, are described: Creptotrema conconae n. sp. (type-host, Imparfinis mirini Haseman), Creptotrema schubarti n. sp. (type-host, Characidium schubarti Travassos) and Creptotrema megacetabularis n. sp. (type-host, Auchenipterus osteomystax (Miranda Ribeiro)). The diagnosis of the genus was amended to include new features. The new species differ from each other mainly in terms of body shape, relative sucker size, and testes position. DNA sequences were obtained from Creptotrema spp. from Brazil, including 28S, ITS and COI. Genetic divergences among the new species and C. creptotrema varied from 2.1 to 5.2% (21-49 bp) for 28S, and 6.6 to 16.4% (21-45 bp) for COI. Phylogenetic analysis (28S) placed the newly generated DNA sequences of Creptotrema in a clade (Creptotrema clade sensu stricto) composed of C. creptotrema, the new species described herein, and all species previously described as Auriculostoma, revealing that Auriculostoma is best interpreted as a synonym of Creptotrema based on the principle of priority of zoological nomenclature. Creptotrema funduli, the single sequence of the genus previously available, was not grouped within the Creptotrema clade sensu stricto, suggesting the need for reevaluation of the taxonomic status of this species. Our results showed that Creptotrema represents a monophyletic genus of trematodes widely distributed across the Americas, which currently comprises 19 valid species of parasites of teleosts and anurans.


TITLE: Trois nouvelles espèces de Creptotrema (Trematoda, Allocreadiidae) avec diagnostic modifié du genre et une réattribution d'Auriculostoma (Allocreadiidae) sur la base de preuves morphologiques et moléculaires. ABSTRACT: La diversité de Creptotrema a été étudiée à l'aide d'outils morphologiques et moléculaires, incluant des données pour Creptotrema creptotrema (espèce-type). Trois nouvelles espèces, parasites de poissons brésiliens, sont décrites : Creptotrema conconae n. sp. (hôte-type, Imparfinis mirini Haseman), Creptotrema schubarti n. sp. (hôte-type, Characidium schubarti Travassos) et Creptotrema megacetabularis n. sp. (hôte-type, Auchenipterus osteomystax (Miranda Ribeiro)). Le diagnostic du genre a été modifié pour inclure de nouvelles caractéristiques. Les nouvelles espèces diffèrent les unes des autres principalement en termes de forme du corps, de taille relative des ventouses et de position des testicules. Des séquences d'ADN ont été obtenues de Creptotrema spp. du Brésil, y compris 28S, ITS et COI. Les divergences génétiques entre les nouvelles espèces et C. creptotrema variaient de 2,1 à 5,2 % (21 à 49 pb) pour les séquences 28S, et de 6,6 à 16,4 % (21 à 45 pb) pour le COI. L'analyse phylogénétique (28S) a placé les séquences d'ADN nouvellement générées de Creptotrema dans un clade (Creptotrema clade sensu stricto) composé de C. creptotrema, les nouvelles espèces décrites ici et toutes les espèces précédemment décrites comme Auriculostoma, révélant qu'Auriculostoma est mieux interprété comme un synonyme de Creptotrema sur la base du principe de priorité de la nomenclature zoologique. Creptotrema funduli, la seule séquence du genre précédemment disponible, n'a pas été regroupée au sein du clade Creptotrema sensu stricto, ce qui suggère la nécessité d'une réévaluation du statut taxonomique de cette espèce. Nos résultats montrent que Creptotrema est un genre monophylétique de trématodes largement distribué à travers les Amériques, qui comprend actuellement 19 espèces valides, parasites de téléostéens et d'anoures.


Subject(s)
Characiformes , Fish Diseases , Trematoda , Trematode Infections , Animals , Fish Diseases/diagnosis , Phylogeny , RNA, Ribosomal, 28S , Trematoda/genetics , Trematode Infections/diagnosis , Trematode Infections/veterinary
4.
Blood Cells Mol Dis ; 89: 102570, 2021 07.
Article in English | MEDLINE | ID: mdl-33962291

ABSTRACT

Hemophilia A and hemophilia B are X-linked inherited bleeding disorders caused by a deficiency of coagulation factor VIII and IX, respectively. Standard of care is prophylactic factor replacement therapy; however, the development of neutralizing antibodies against these factors represents serious complications underlining the need for alternative treatment approaches. Human coagulation factor X has a central role within the blood coagulation system making it an attractive target for the development of alternative treatment strategies for patients with hemophilia. This study focuses on a modified variant of the human coagulation factor X with enhanced hemostatic bypass activity due to insertion of a factor IX derived activation sequence. This molecule design leads to the direct activation of the modified factor X protein by factor XIa allowing it to bypass the need for coagulation factor VIIIa/factor IXa. The modified variant was able to correct in-vitro activated partial prothrombin time of human and murine factor VIII/factor IX deficient plasma. Furthermore, reduced blood loss in factor VIII knock-out mice was observed after intravenous application of the modified factor X variant. In conclusion, these data suggest that the factor X variant described here could potentially serve as a bypassing agent independent of the inhibitor status of hemophilia patients. However, more research is needed to further investigate the potential of this molecule.


Subject(s)
Blood Coagulation/drug effects , Factor X/pharmacology , Hemostatics/pharmacology , Animals , Factor X/therapeutic use , Female , Hemophilia A/blood , Hemophilia A/drug therapy , Hemorrhage/blood , Hemorrhage/drug therapy , Hemostatics/therapeutic use , Humans , Male , Mice , Partial Thromboplastin Time , Recombinant Proteins/pharmacology , Recombinant Proteins/therapeutic use
5.
Parasitol Res ; 120(3): 971-977, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33409642

ABSTRACT

Two digenean species, Infidum infidum Faria, 1910 (Dicrocoeliidae) and Travtrema stenocotyle Cohn, 1902 (Plagiorchiidae), were collected in the large pit viper Bothrops moojeni Hoge, 1966 from Reserva Particular do Patrimônio Natural Cisalpina, municipality of Brasilândia, Mato Grosso do Sul State, Brazil. In this study, we provide the first molecular characterisation using the 28S rDNA and phylogenetic position data of these two common digeneans from B. moojeni. The molecular framework revealed topologies with strongly supported clades using maximum likelihood and Bayesian inference methods, positioned I. infidum among Plagiorchiidae and not among Dicrocoeliidae as expected and T. stenocotyle (Plagiorchiidae) surprisingly grouped as a sister group to Allassogonoporidae, Microphallidae, Pleurogenidae, and Prosthogonimidae, not related to plagiorchids. Our molecular phylogenetic data showed that these species may not correspond to their assigned families and encourage future studies on the systematic of these understudied groups.


Subject(s)
Bothrops/parasitology , Phylogeny , Trematoda/classification , Trematode Infections/veterinary , Animals , Brazil , DNA, Helminth/genetics , DNA, Ribosomal/genetics , RNA, Ribosomal, 28S/genetics , Trematoda/genetics , Trematoda/isolation & purification , Trematode Infections/parasitology
6.
Parasitol Res ; 120(1): 347-353, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33169307

ABSTRACT

We report for the first time the infection of dolphins with Ascocotyle longa found in the intestines of three different species, Sotalia guianensis, Steno bredanensis, and Tursiops truncatus gephyreus, which were found washed ashore along the southeastern and southern Brazilian coast. The worms were identified based on morphological and molecular data using the 28S rDNA gene and the COI gene. Specimens of A. longa from the pinniped Otaria flavescens were also analyzed. As the first isolation of A. longa from cetaceans, the present study increases the distribution area and range of definitive hosts of this trematode, and provides new molecular data to complement the phylogeny of the group in future studies, thus contributing to the scientific knowledge of this potentially zoonotic parasite.


Subject(s)
Bottle-Nosed Dolphin/parasitology , Heterophyidae , Trematode Infections/veterinary , Animals , Atlantic Ocean , Brazil , Electron Transport Complex IV/genetics , Heterophyidae/classification , Heterophyidae/genetics , Heterophyidae/isolation & purification , Intestines/parasitology , RNA, Ribosomal, 28S/genetics , Trematode Infections/parasitology
7.
BMC Vet Res ; 16(1): 153, 2020 May 24.
Article in English | MEDLINE | ID: mdl-32448250

ABSTRACT

BACKGROUND: Penguin interaction with gillnets has been extensively reported in the Atlantic and Pacific Oceans, and is considered a major conservation threat. Among penguin species, Magellanic penguins (Spheniscus magellanicus) are currently considered of great concern, particularly in Brazil, where they are highly susceptible to gillnet bycatch. Nevertheless, information about drowning-associated microscopic findings in penguins is limited. RESULTS: We describe the anatomopathological findings of 20 Magellanic penguins that drowned after getting entangled in a drift gillnet while wintering along the Brazilian shelf and washed ashore still enmeshed in Santa Catarina, Brazil. All 20 birds (19 juveniles and 1 adult; 18 females and 2 males) were in good body condition. Major gross findings were abrasion, bruising, and local erythema and edema of the wings, multiorgan congestion, jugular vein engorgement, pulmonary edema and hemorrhage, splenomegaly and hepatomegaly, fluid in the trachea, serous bloody fluid in the lungs, gastrointestinal parasites (nematodes, cestodes and trematodes), and debris in the stomach. The most common histopathological findings were cerebral and pulmonary congestion, pulmonary edema, splenic histiocytosis, lymphoid splenic hyperplasia, acute splenitis, extramedullary hepatic hematopoiesis, and parasitic enteritis. Although unspecific, the observed multiorgan congestion and pulmonary edema are consistent with previous reports of drowning in birds and may be indicative of this process. CONCLUSIONS: Drowning may be a challenging diagnosis (e.g., carcass decomposition, predation), but must be considered as a differential in all beach-cast seabird postmortem examinations. To the authors' knowledge this is the largest anatomopathological study based on microscopic examination in drowned penguins.


Subject(s)
Bird Diseases/pathology , Drowning/veterinary , Spheniscidae , Animals , Autopsy/veterinary , Bird Diseases/etiology , Bird Diseases/parasitology , Brazil , Drowning/pathology , Female , Fisheries , Male , Pulmonary Edema/veterinary
8.
Parasitol Res ; 116(5): 1443-1452, 2017 May.
Article in English | MEDLINE | ID: mdl-28293739

ABSTRACT

A new species of Synthesium from the bottlenose dolphin Tursiops truncatus in South Brazilian waters is described. Morphological and molecular identification was performed, and phylogenetic analyses were carried out using the ribosomal small subunit and internal transcribed spacer 1 and the mitochondrial NDH dehydrogenase subunit 3 and cytochrome c oxidase subunit 1 genes. The main characteristics of the new species are the subterminal round-shaped oral sucker, the anterior distribution of vitellaria reaching the level of the ovary and the oval-shaped testes. The results obtained with the molecular markers supported the inclusion of the specimens into the genus Synthesium. The nucleotide divergence detected for the mitochondrial genes among the new species and others of the same genus supported the erection of a new species. This is the ninth species assigned to the genus and the third Synthesium species recorded in the South Atlantic Ocean.


Subject(s)
Bottle-Nosed Dolphin/parasitology , Trematoda/classification , Trematoda/isolation & purification , Trematode Infections/veterinary , Animals , Atlantic Ocean , Brazil , Carbohydrate Dehydrogenases/genetics , DNA, Intergenic/genetics , Electron Transport Complex IV/genetics , Female , Male , Phylogeny , Ribosome Subunits, Small/genetics , Trematoda/genetics , Trematode Infections/parasitology
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