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1.
Syst Parasitol ; 97(1): 107-118, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31912418

RESUMO

Macropsylla Rothschild, 1905 is an endemic Australian flea genus represented by two species: M. hercules Rothschild, 1905 and M. novaehollandiae Hastriter, 2002. However, their identification is challenging. To address this difficulty, an extensive differential diagnosis for the two species is provided along with a key to distinguish Macropsylla from other Australian flea genera. The first record of M. hercules from the domestic cat (Felis catus (L.)) is also presented. The taxonomy, distribution, host relationships, evolution, and ecology of the Macropsylla species are discussed, along with the conservation biology of the threatened New Holland flea M. novaehollandiae.


Assuntos
Aves/parasitologia , Mamíferos/parasitologia , Sifonápteros/classificação , Sifonápteros/fisiologia , Animais , Austrália , Conservação dos Recursos Naturais , Especificidade de Hospedeiro , Filogenia , Especificidade da Espécie
2.
BMC Genomics ; 20(1): 729, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606027

RESUMO

BACKGROUND: The tropical liver fluke, Fasciola gigantica causes fasciolosis, an important disease of humans and livestock. We characterized dynamic transcriptional changes associated with the development of the parasite in its two hosts, the snail intermediate host and the mammalian definitive host. RESULTS: Differential gene transcription analysis revealed 7445 unigenes transcribed by all F. gigantica lifecycle stages, while the majority (n = 50,977) exhibited stage-specific expression. Miracidia that hatch from eggs are highly transcriptionally active, expressing a myriad of genes involved in pheromone activity and metallopeptidase activity, consistent with snail host finding and invasion. Clonal expansion of rediae within the snail correlates with increased expression of genes associated with transcription, translation and repair. All intra-snail stages (miracidia, rediae and cercariae) require abundant cathepsin L peptidases for migration and feeding and, as indicated by their annotation, express genes putatively involved in the manipulation of snail innate immune responses. Cercariae emerge from the snail, settle on vegetation and become encysted metacercariae that are infectious to mammals; these remain metabolically active, transcribing genes involved in regulation of metabolism, synthesis of nucleotides, pH and endopeptidase activity to assure their longevity and survival on pasture. Dramatic growth and development following infection of the mammalian host are associated with high gene transcription of cell motility pathways, and transport and catabolism pathways. The intra-mammalian stages temporally regulate key families of genes including the cathepsin L and B proteases and their trans-activating peptidases, the legumains, during intense feeding and migration through the intestine, liver and bile ducts. While 70% of the F. gigantica transcripts share homology with genes expressed by the temperate liver fluke Fasciola hepatica, gene expression profiles of the most abundantly expressed transcripts within the comparable lifecycle stages implies significant species-specific gene regulation. CONCLUSIONS: Transcriptional profiling of the F. gigantica lifecycle identified key metabolic, growth and developmental processes the parasite undergoes as it encounters vastly different environments within two very different hosts. Comparative analysis with F. hepatica provides insight into the similarities and differences of these parasites that diverged > 20 million years ago, crucial for the future development of novel control strategies against both species.


Assuntos
Fasciola/crescimento & desenvolvimento , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Mamíferos/parasitologia , Caramujos/parasitologia , Animais , Evolução Molecular , Fasciola/genética , Regulação da Expressão Gênica , Especificidade de Hospedeiro , Humanos , Estágios do Ciclo de Vida , Família Multigênica , Proteínas de Protozoários/genética
3.
Acta Trop ; 199: 105098, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31356788

RESUMO

Distinct species of Trypanosoma have been documented sharing the same hosts in different environments in intricate transmission networks. Knowing this, this study investigated the role of different hosts in the transmission cycles of Trypanosoma species in the Pantanal biome. The mammals were sampled from November 2015 to October 2016. We sampled a total of 272 wild mammals from 27 species belonging to six orders and 15 families, and three species of triatomines (n = 7). We found high parasitemias by Hemoculture test for Trypanosoma cruzi (TcI), Trypanosoma rangeli, Trypanosoma cruzi marinkellei and Trypanosoma dionisii, and high parasitemias by Microhematocrit Centrifuge Technique for Trypanosoma evansi. The carnivore Nasua nasua is a key host in the transmission cycles since it displayed high parasitemias for T. cruzi, T. evansi and T. rangeli. This is the first report of high parasitemias in Tamandua tetradactyla and cryptic infection in Dasypus novemcinctus by T. cruzi; cryptic infection by T. evansi in Eira barbara, Euphractus sexcinctus and Dasyprocta azarae. The collection of Panstrongylus geniculatus increased the geographic distribution of this vector species in the South America. Our results indicate that Trypanosoma species circulate in a complex reservoir system including different host species with different infective competences.


Assuntos
Reservatórios de Doenças/parasitologia , Trypanosoma/isolamento & purificação , Tripanossomíase/transmissão , Áreas Alagadas , Animais , Mamíferos/parasitologia , Parasitemia/epidemiologia , Parasitemia/veterinária , Triatoma/parasitologia
4.
J Helminthol ; 93(6): 649-676, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31232245

RESUMO

Marine mammals are long-lived top predators with vagile lifestyles, which often inhabit remote environments. This is especially relevant in the oceanic waters around New Zealand and Australia where cetaceans and pinnipeds are considered as vulnerable and often endangered due to anthropogenic impacts on their habitat. Parasitism is ubiquitous in wildlife, and prevalence of parasitic infections as well as emerging diseases can be valuable bioindicators of the ecology and health of marine mammals. Collecting information about parasite diversity in marine mammals will provide a crucial baseline for assessing their impact on host and ecosystem ecology. New studies on marine mammals in New Zealand and Australian waters have recently added to our knowledge of parasite prevalence, life cycles and taxonomic relationships in the Australasian region, and justify a first host-parasite checklist encompassing all available data. The present checklist comprises 36 species of marine mammals, and 114 species of parasites (helminths, arthropods and protozoans). Mammal species occurring in New Zealand and Australian waters but not included in the checklist represent gaps in our knowledge. The checklist thus serves both as a guide for what information is lacking, as well as a practical resource for scientists working on the ecology and conservation of marine mammals.


Assuntos
Mamíferos/parasitologia , Parasitos/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Animais , Austrália , Lista de Checagem , Ecossistema , Mamíferos/classificação , Nova Zelândia , Oceanos e Mares , Parasitos/classificação , Parasitos/genética
5.
Turkiye Parazitol Derg ; 43(2): 83-88, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31204461

RESUMO

In all major parasite groups, new and surprising evidence is emerging every day about the subtlety, complexity and diversity of avoidance mechanisms from host immune system. In the course of millions of years of evolutionary process, mammalian and sand fly hosts have developed defense systems against Leishmania, but Leishmania has not only escaped from their hosts' defense systems through complex counter-strategies, but has also managed to manipulate them to support their own survival and reproduction. In this study, Leishmania's survival strategies used in the sand fly and mammalian hosts and the mechanisms that underlie these strategies will be summarized.


Assuntos
Leishmania/fisiologia , Mamíferos/parasitologia , Psychodidae/parasitologia , Animais , Leishmania/imunologia , Mamíferos/imunologia , Phlebotomus/imunologia , Phlebotomus/parasitologia , Psychodidae/imunologia
6.
Exp Appl Acarol ; 78(3): 461-467, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31168752

RESUMO

Zoonotic diseases transmitted through ticks and other ectoparasites often travel across the globe with illegally traded wildlife parts and products. In this study, we analyzed a confiscated case of pangolin scales and observed a few dead ticks attached. On genetic analysis, the pangolin scales were identified to be originated from Chinese pangolin (Manis pentadactyla), an IUCN listed Critically Endangered species, and ticks were identified as Amblyomma javanense. Here, we provide the first authentic physical record of A. javanense from India as a parasite of Chinese pangolin and also generated its species DNA barcode that may be useful for biologists working on ticks in species validation and constructing phylogenies across the globe.


Assuntos
Conservação dos Recursos Naturais , Ciências Forenses , Ixodidae/genética , Animais , Código de Barras de DNA Taxonômico , Espécies em Perigo de Extinção , Ixodidae/classificação , Ixodidae/fisiologia , Mamíferos/parasitologia , Filogenia , Medição de Risco , Doenças Transmitidas por Carrapatos/transmissão
7.
Yale J Biol Med ; 92(2): 225-231, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31249483

RESUMO

From bacteria to mammals, nearly all organisms have adapted their physiology and behavior to a daily rhythm. These circadian (daily) rhythms influence virtually all aspects of physiological architecture (i.e., from gene expression to organismal behavior). Therefore, it is not surprising that several features of the immune response are regulated in a time-of-day dependent manner. The field of chrono-immunology has expanded tremendously over the past decade. In this abridged review, we present studies from the past five years that have revealed new parameters of the immune system that demonstrate daily variations in the control of pathogens and response to microbial components. These studies analyzed how the disruption of circadian rhythms impairs immune function, how microbial components alter the circadian clock, and how immune responses demonstrate daily variations in human subjects. Further elucidating the intricate connections between the circadian clock and the immune system will hopefully provide opportunities for chrono-immunotherapy in disease treatment and prevention.


Assuntos
Relógios Circadianos/imunologia , Ritmo Circadiano/imunologia , Sistema Imunitário/imunologia , Mamíferos/imunologia , Animais , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/imunologia , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Regulação da Expressão Gênica/imunologia , Humanos , Sistema Imunitário/microbiologia , Sistema Imunitário/parasitologia , /parasitologia , Mamíferos/microbiologia , Mamíferos/parasitologia
8.
Parasit Vectors ; 12(1): 230, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088533

RESUMO

BACKGROUND: Peritoneal larval cestodiasis induced by Mesocestoides Vaillant, 1863 (Cyclophyllidea: Mesocestoididae) is a common cause of severe infections in domestic dogs and cats, reported also from other mammals and less frequently from birds. However, there is a limited knowledge on the taxonomy of causative agents of this disease. RESULTS: In the present study, we investigated a massive, likely lethal, infection of a song thrush Turdus philomelos (Passeriformes: Turdidae) by Mesocestoides sp. tetrathyridia. We performed combined morphological and phylogenetic analysis of the tetrathyridia and compared them with the materials obtained previously from other birds and mammals. The metrical data fitted within the wide range reported by previous authors but confirmed the limited value of morphological data for species identification of tetrathyridia of Mesocestoides spp. The molecular analyses suggested that the isolates represented an unidentified Mesocestoides sp. that was previously repeatedly isolated and sequenced in larval and adult forms from domestic dogs and cats in Europe, the Middle East and North Africa. In contrast to the present study, which found encysted tetrathyridia, four of the five previous studies that identified the same species described infections by acephalic metacestodes only. CONCLUSIONS: The tetrathyridia of the examined Mesocestoides sp. are described in the present study for the first time. However, the possible match with the species that were previously reported to infect birds remains uncertain. The phylogenetic analyses also suggested the rejection of two cases that were previously identified as Mesocestoides corti as they were likely caused by the same species as in the presently reported infection case. The newly provided DNA sequences should allow the assignment to species in the future, when adults of the genus Mesocestoides are more thoroughly sequenced.


Assuntos
Cisticercose/veterinária , Mamíferos/parasitologia , Mesocestoides/genética , Animais de Estimação/parasitologia , Aves Canoras/parasitologia , Animais , Sequência de Bases , Doenças do Gato/parasitologia , Doenças do Gato/transmissão , Gatos , Cisticercose/transmissão , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Evolução Fatal , Feminino , Mesocestoides/patogenicidade , Filogenia
9.
Ticks Tick Borne Dis ; 10(4): 830-837, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30981671

RESUMO

Hard tick diversity was determined along the Oleoducto trail (OT), Soberania National Park, from February 2013 to September 2014. Ticks were surveyed at four sites of 500 m2 each and with increasing forest cover gradient and decreasing disturbance. Tick collections were made by dragging and flagging vegetation, and traps and mist nets were used to capture mammals and birds. Animals confiscated from poachers were also examined. To obtain information about potential hosts along the trail, 20 camera traps were used. 1536 ticks were collected, representing 20 species; of these, 1089 were questing ticks (10 species) collected on flags. We examined 143 birds (30 species) and 59 mammals (10 species), of which 40 birds and 36 mammals had ticks. Site 1 presented the lowest number of species and also the lowest number of potential hosts. Artiodactyls were the most frequent mammals photographed in camera traps, and ticks that parasitize these animals were among the most abundant in sites 2-4. Of these, Haemaphysalis juxtakochi was the most abundant species. Differences among sites were consistent with the gradient of forest cover, disturbance along OT and distribution of potential hosts.


Assuntos
Ixodidae/classificação , Mamíferos/parasitologia , Parques Recreativos , Infestações por Carrapato/veterinária , Animais , Aves/parasitologia , Larva , Panamá , Densidade Demográfica , Floresta Úmida , Inquéritos e Questionários , Infestações por Carrapato/epidemiologia
10.
Med Vet Entomol ; 33(3): 360-366, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30883848

RESUMO

Determination of the ratios of natural stable isotopes (13 C/12 C and 15 N/14 N) in unfed Ixodes ricinus nymphs and adults, which, in their previous stage, fed on captive wild rodents (Apodemus sylvaticus and Myodes glareolus), wild birds (Parus major and Cyanistes caeruleus) or domestic ruminants (Ovis aries and Bos taurus), demonstrated that it is possible to identify each host category with confidence. First, the tick-blood spacing, which is the difference between values obtained from ticks and the blood of hosts that they had fed on in the previous stage, was consistent (152 spacings investigated from 15 host individuals in total). Second, potential confounding factors (tick age and sex) did not affect the discriminatory power of the isotope patterns, nor did different rearing conditions (room temperature vs. 4 °C) or the duration of development (maximum of 430 days). The findings that the tick-blood isotope spacings, across a diverse range of hosts, were similar and predictable, and that confounders had little or no effect on this, strongly support the usage of the isotope approach. Because each of the host categories has a different role in the population dynamics of I. ricinus and in tick-borne pathogen ecology, the method described here has great potential for the clarification of tick and tick-borne pathogen ecology in the field.


Assuntos
Aves/parasitologia , Isótopos de Carbono/análise , Interações Hospedeiro-Parasita , Ixodes/fisiologia , Mamíferos/parasitologia , Isótopos de Nitrogênio/análise , Animais , Diapausa , Feminino , Ixodes/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/fisiologia , Masculino , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Especificidade da Espécie , Temperatura
11.
Arch Insect Biochem Physiol ; 102(3): e21544, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30859631

RESUMO

Ticks are obligate blood-sucking ectoparasites, which not only directly damage through bites but also transmit many pathogens. China has a high diversity of tick species, 125 species have been reported, including 111 hard tick and 14 soft tick species. Many of the ticks are important vectors of pathogens, resulting in zoonoses. The dynamics of ticks are affected by both the host and habitat environment. However, systematic studies on the geographical distribution, host diversity, and specificity of ticks are limited in China. To achieve this goal, the relevant available data were summarized and analyzed in this study. Ticks are distributed in all parts of China and Xinjiang has the most records of ticks. The distribution of ticks in adjacent areas is similar, indicating that the habitat environment affects their distribution. Most ticks are widely distributed, whereas some species are endemic to their distributed regions. Ticks are parasitic on mammals, birds, and reptiles, of which mammals are the main host species. Overall, most ticks parasitize different hosts, only a few ticks have strict host specificity, such as ticks that are specifically parasitic on reptiles and bats. In addition, environmental changes and control efforts also influence the dynamics of ticks. These results can better reveal tick biological traits and are valuable for tick control.


Assuntos
Interações Hospedeiro-Parasita , Carrapatos/classificação , Animais , Aves/parasitologia , China , Ecossistema , Geografia , Mamíferos/parasitologia , Répteis/parasitologia
12.
PLoS Negl Trop Dis ; 13(2): e0007170, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30768613

RESUMO

BACKGROUND: Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is maintained in non-domestic foci. The aim of this study was to describe T. cruzi infection and DTU composition in mammals and triatomines from several non-domestic populations of North-Central Chile and to evaluate their spatio-temporal variations. METHODOLOGY/PRINCIPAL FINDINGS: A total of 710 small mammals and 1140 triatomines captured in six localities during two study periods (summer/winter) of the same year were analyzed by conventional PCR to detect kDNA of T. cruzi. Positive samples were DNA blotted and hybridized with specific probes for detection of DTUs TcI, TcII, TcV, and TcVI. Infection status was modeled, and cluster analysis was performed in each locality. We detected 30.1% of overall infection in small mammals and 34.1% in triatomines, with higher rates in synanthropic mammals and in M. spinolai. We identified infecting DTUs in 45 mammals and 110 triatomines, present more commonly as single infections; the most frequent DTU detected was TcI. Differences in infection rates among species, localities and study periods were detected in small mammals, and between triatomine species; temporally, infection presented opposite patterns between mammals and triatomines. Infection clustering was frequent in vectors, and one locality exhibited half of the 21 clusters found. CONCLUSIONS/SIGNIFICANCE: We determined T. cruzi infection in natural host and vector populations simultaneously in a spatially widespread manner during two study periods. All captured species presented T. cruzi infection, showing spatial and temporal variations. Trypanosoma cruzi distribution can be clustered in space and time. These clusters may represent different spatial and temporal risks of transmission.


Assuntos
Doença de Chagas/parasitologia , Insetos Vetores/parasitologia , Mamíferos/parasitologia , Triatoma/parasitologia , Trypanosoma cruzi/genética , Animais , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Chile/epidemiologia , Análise por Conglomerados , Genótipo , Humanos
13.
Acta Parasitol ; 64(2): 406-410, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30762224

RESUMO

BACKGROUND: Despite being a significant element of biodiversity and playing an important role in their hosts' physiology, ecology and evolution, parasites remain understudied and are often neglected during biotic surveys and other collection efforts. More often than not, it is due to the perception that parasitological examination requires specialized expertise and substantial additional time to perform. RESULTS: Herein, we provide an express method for recovery and fixation of endoparasites from the gastrointestinal tract of small mammals that can be used by both parasitologists and vertebrate biologists in either field or laboratory conditions. The method does not require special training beyond minimal practice and does not need optics or other special equipment. DISCUSSION: Our goal is to encourage collection of endoparasites as part of biotic surveys by vertebrate biologists to provide valuable additional biodiversity information in cases when a traditional complete parasitological examination of hosts is not feasible. We believe that this technique will also be useful for professional parasitologists.


Assuntos
Trato Gastrointestinal/parasitologia , Helmintos/isolamento & purificação , Técnicas de Preparação Histocitológica , Mamíferos/parasitologia , Manejo de Espécimes/métodos , Animais , Musaranhos/parasitologia
14.
Parasitol Res ; 118(4): 1113-1125, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30778750

RESUMO

We tested whether biogeographic patterns characteristic of species diversity and composition may also apply to community assembly by investigating geographic variation in the pattern (PSA) (aggregation versus segregation) and strength of species associations (SSA) in flea and mite communities harbored by small mammalian hosts in Western Siberia. We asked whether (a) there is a relationship between latitude and PSA or SSA and (b) similarities in PSA or SSA follow a distance decay pattern or if they are better explained by variation in environmental factors (altitude, amount of vegetation, precipitation, and air temperature). We used a sign of a co-occurrence metric (the C-score) as an indicator of PSA and its absolute standardized value as a measure of SSA. We analyzed data using logistic and linear models, generalized dissimilarity modeling (GDM), and a logistic version of the multiple regression on distance matrices (MRM). The majority of the C-scores of the observed presence/absence matrices indicated a tendency to species aggregation rather than segregation. No effect of latitude on PSA or SSA was found. The dissimilarity in PSA was affected by environmental dissimilarity in mite compound communities only. A relatively large proportion of the deviance of spatial variation in SSA was explained by the GDMs in infracommunities, but not component communities, and in only three (of seven) and two (of eight) host species of fleas and mites, respectively. The best predictors of dissimilarity in SSA in fleas differed between host species, whereas the same factor (precipitation) was the best predictor of dissimilarity in SSA in mites. We conclude that PSA and SSA in parasite communities rarely conform to biogeographic rules. However, when a biogeographic pattern is detected, its manifestation differs among hosts and between ectoparasite taxa.


Assuntos
Meio Ambiente , Geografia , Mamíferos/parasitologia , Ácaros/crescimento & desenvolvimento , Parasitos/crescimento & desenvolvimento , Sifonápteros/crescimento & desenvolvimento , Animais , Infestações por Pulgas , Interações Hospedeiro-Parasita , Sibéria
15.
Rev Bras Parasitol Vet ; 28(1): 168-171, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30785552

RESUMO

Animals reared in restricted environments are highly susceptible to gastrointestinal infection by helminths and protozoa and therefore zoos are characterized as being parasite-rich environments. Successful implementation of control programs of these parasites in zoo environment depends upon precise and rapid diagnosing of gastrointestinal infections. The aim of this study was to demonstrate the role of the Mini-FLOTAC technique in combination with Fill-FLOTAC for rapidly diagnosing parasitic infections in zoo mammals. Fecal samples were collected from 70 animals in four different zoos located in central and southern Italy. All the samples were analyzed using Mini-FLOTAC in combination with Fill-FLOTAC. Out of the 70 pooled samples examined, 80% (24/30) were positive for at least one parasite. Among the gastrointestinal nematodes, Strongyles were the most frequent (40%), followed by Trichuris spp. (23.3%), Parascaris spp. (13.3%) and Capillaria spp. (3.3%). Among the protozoa, Blastocystis spp., Giardia spp. and Eimeria spp. were detected in 6.6%, 3.3% and 3.3%, respectively. These results show that Mini-FLOTAC in combination with Fill-FLOTAC can be used, not only for rapidly diagnosing parasitic infections in zoo mammals, but also for monitoring control programs in which large numbers of fecal samples need to be examined rapidly and reliably.


Assuntos
Animais de Zoológico/parasitologia , Gastroenteropatias/veterinária , Helmintíase Animal/diagnóstico , Mamíferos/parasitologia , Doenças Parasitárias em Animais/diagnóstico , Infecções por Protozoários/diagnóstico , Animais , Fezes/parasitologia , Gastroenteropatias/diagnóstico , Gastroenteropatias/parasitologia , Helmintíase Animal/parasitologia , Doenças Parasitárias em Animais/parasitologia , Infecções por Protozoários/parasitologia , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
16.
RNA Biol ; 16(5): 639-660, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30689499

RESUMO

Leishmaniasis is a worldwide public health problem caused by protozoan parasites of the genus Leishmania. Leishmania braziliensis is the most important species responsible for tegumentary leishmaniases in Brazil. An understanding of the molecular mechanisms underlying the success of this parasite is urgently needed. An in-depth study on the modulation of gene expression across the life cycle stages of L. braziliensis covering coding and noncoding RNAs (ncRNAs) was missing and is presented herein. Analyses of differentially expressed (DE) genes revealed that most prominent differences were observed between the transcriptomes of insect and mammalian proliferative forms (6,576 genes). Gene ontology (GO) analysis indicated stage-specific enriched biological processes. A computational pipeline and 5 ncRNA predictors allowed the identification of 11,372 putative ncRNAs. Most of the DE ncRNAs were found between the transcriptomes of insect and mammalian proliferative stages (38%). Of the DE ncRNAs, 295 were DE in all three stages and displayed a wide range of lengths, chromosomal distributions and locations; many of them had a distinct expression profile compared to that of their protein-coding neighbors. Thirty-five putative ncRNAs were submitted to northern blotting analysis, and one or more hybridization-positive signals were observed in 22 of these ncRNAs. This work presents an overview of the L. braziliensis transcriptome and its adjustments throughout development. In addition to determining the general features of the transcriptome at each life stage and the profile of protein-coding transcripts, we identified and characterized a variety of noncoding transcripts. The novel putative ncRNAs uncovered in L. braziliensis might be regulatory elements to be further investigated.


Assuntos
Perfilação da Expressão Gênica/métodos , Leishmania braziliensis/crescimento & desenvolvimento , RNA de Protozoário/genética , Análise de Sequência de RNA/métodos , Animais , Brasil , Biologia Computacional/métodos , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Humanos , Insetos/parasitologia , Leishmania braziliensis/genética , Mamíferos/parasitologia , RNA não Traduzido/genética
17.
Parasit Vectors ; 12(1): 32, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30642380

RESUMO

BACKGROUND: Toxocara canis is quite closely related to Ascaris suum but its biology is more complex, involving a phase of arrested development (diapause or hypobiosis) in tissues as well as transplacental and transmammary transmission routes. In the present study, we explored and compared dauer-like signalling pathways of T. canis and A. suum to infer which components in these pathways might associate with, or regulate, this added complexity in T. canis. METHODS: Guided by information for Caenorhabditis elegans, we bioinformatically inferred and compared components of dauer-like signalling pathways in T. canis and A. suum using genomic and transcriptomic data sets. In these two ascaridoids, we also explored endogenous dafachronic acids (DAs), which are known to be critical in regulating larval developmental processes in C. elegans and other nematodes, by liquid chromatography-mass spectrometry (LC-MS). RESULTS: Orthologues of C. elegans dauer signalling genes were identified in T. canis (n = 55) and A. suum (n = 51), inferring the presence of a dauer-like signalling pathway in both species. Comparisons showed clear differences between C. elegans and these ascaridoids as well as between T. canis and A. suum, particularly in the transforming growth factor-ß (TGF-ß) and insulin-like signalling pathways. Specifically, in both A. suum and T. canis, there was a paucity of genes encoding SMAD transcription factor-related protein (daf-3, daf-5, daf-8 and daf-14) and insulin/insulin-like peptide (daf-28, ins-4, ins-6 and ins-7) homologues, suggesting an evolution and adaptation of the signalling pathway in these parasites. In T. canis, there were more orthologues coding for homologues of antagonist insulin-like peptides (Tc-ins-1 and Tc-ins-18), an insulin receptor substrate (Tc-ist-1) and a serine/threonine kinase (Tc-akt-1) than in A. suum, suggesting potentiated functional roles for these molecules in regulating larval diapause and reactivation. A relatively conserved machinery was proposed for DA synthesis in the two ascaridoids, and endogenous Δ4- and Δ7-DAs were detected in them by LC-MS analysis. Differential transcription analysis between T. canis and A. suum suggests that ins-17 and ins-18 homologues are specifically involved in regulating development and migration in T. canis larvae in host tissues. CONCLUSION: The findings of this study provide a basis for functional explorations of insulin-like peptides, signalling hormones (i.e. DAs) and related nuclear receptors, proposed to link to development and/or parasite-host interactions in T. canis. Elucidating the functional roles of these molecules might contribute to the discovery of novel anthelmintic targets in ascaridoids.


Assuntos
Biologia Computacional , Mamíferos/parasitologia , Transdução de Sinais/fisiologia , Toxocara canis/fisiologia , Sequência de Aminoácidos , Animais , Ascaris suum/fisiologia , Caenorhabditis elegans , Sequência Conservada , Regulação da Expressão Gênica , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Interações Hospedeiro-Parasita , Modelos Biológicos , Toxocara canis/genética
18.
Ticks Tick Borne Dis ; 10(2): 442-453, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30611725

RESUMO

This study evaluated the species richness and seasonal dynamics of ticks and rickettsial agents infecting ticks in the largest natural Reserve of the Cerrado biome of Brazil, the Grande Sertão Veredas National Park. During 2012-2014, a total of 9531 host-seeking ticks were collected by dry ice traps and dragging, whereas 1563 ticks were collected from small mammals, and 1186 ticks from domestic animals. Overall, the following 12 tick species were identified: Amblyomma auricularium, Amblyomma dubitatum, Amblyomma naponense, Amblyomma ovale, Amblyomma parvum, Amblyomma sculptum, Amblyomma tigrinum, Amblyomma triste, Dermacentor nitens, Rhipicephalus microplus, Rhipicephalus sanguineus sensu lato, and Ornithodoros mimon. The three most abundant tick species, A. sculptum, A. parvum, and A. triste, are likely to develop one generation per year, with adults predominating between spring and autumn, and immature ticks during autumn-winter. Small mammals seem to be important hosts for immature stages of A. parvum, and A. triste, but not for A. sculptum. Molecular analyses revealed the presence of the human pathogen Rickettsia parkeri in 10% of the A. triste ticks, whereas two agents of unknown pathogenicity, Rickettsia bellii and 'Candidatus Rickettsia andeanae' were found in 7 and 5%, respectively, of the A. parvum ticks. A fourth rickettsial agent, Rickettsia amblyommatis, was found in a single A. sculptum tick. Several Vero cell-established isolates of R. parkeri and R. bellii were obtained from A. triste and A. parvum, respectively. Serological analyses of small mammals suggest that they have been infected by R. parkeri and R. bellii, possibly via natural infestations by A. triste and A. parvum, respectively. Because the Park has suffered low anthropic alterations, our results should provide baseline data that shall be used for future comparisons with other Cerrado areas with higher degree of anthropic changes.


Assuntos
Infecções por Rickettsia/veterinária , Estações do Ano , Infestações por Carrapato/veterinária , Carrapatos/microbiologia , Animais , Animais Domésticos/microbiologia , Animais Domésticos/parasitologia , Animais Selvagens/microbiologia , Animais Selvagens/parasitologia , Brasil/epidemiologia , Bovinos , Cães , Ecossistema , Cavalos , Larva/microbiologia , Mamíferos/parasitologia , Ninfa/microbiologia , Parques Recreativos , Rickettsia/isolamento & purificação , Infecções por Rickettsia/epidemiologia , Infestações por Carrapato/epidemiologia
19.
Korean J Parasitol ; 57(6): 647-656, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31914518

RESUMO

Isthmiophora hortensis (Digenea: Echinostomatidae) is a dominant echinostome in animal reservoir hosts and humans in the Republic of Korea (Korea). We intended to investigate the infection status with this echinostome species in the several species of wild animals and describe the morphological characteristics in the faunistic view point. A total of 175 animal carcasses belonging to 3 families, i.e., Canidae, Felidae and Mustelidae, were collected from the southern regions of Korea from March 2010 to July 2017. Isthmiophora spp. worms were recovered from the small intestines of each animal under a stereomicroscope after washing of intestinal contents. Isthmiophora hortensis was recovered from 4 species of wild carnivores, i.e., Nyctereutes procyonoides (3/107: 2.8%), Mustela sibirica (11/31: 35.5%), Meles lucurus (2/3: 33.3%) and Martes flavigula (1/2: 50%). The other 3 carnivores comprising stray dogs, cat and leopard cat were negative for I. hortensis infection (0/2, 0/10 and 0/12, respectively). Specimens obtained from the Lutra lutra (6/8: 75%) were identified as a distinct species, I. inermis, by morphological comparison. Isthmiophora inermis has thinner body, elongate testes and different anterior limits of vitelline fields. Detailed morphological descriptions and comparisons with the morphological characteristics are provided. Conclusively, it was confirmed for the first time that 3 species of mustelid mammals, i.e., M. sibirica, M. lucurus, and M. flavigula, are to be the new definitive hosts of I. hortensis in Korea. Additionally, I. inermis is to be newly added in the Korean echinostome fauna.


Assuntos
Animais Selvagens/parasitologia , Echinostomatidae/isolamento & purificação , Mamíferos/parasitologia , Infecções por Trematódeos/veterinária , Animais , Carnivoridade , Echinostomatidae/classificação , Echinostomatidae/genética , Echinostomatidae/crescimento & desenvolvimento , Mamíferos/classificação , República da Coreia , Infecções por Trematódeos/parasitologia
20.
Parasit Vectors ; 11(1): 633, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30545426

RESUMO

BACKGROUND: Functional inference on the attachment of acanthocephalans has generally been drawn directly from morphology. However, performance of structures is often non-intuitive and context-dependent, thus performance analysis should be included whenever possible to improve functional interpretation. In acanthocephalans, performance analysis of attachment is available only for Acanthocephalus ranae, a species that solely relies on the proboscis to attach. Here we compare body morphology and muscle arrangement in 13 species of Corynosoma, which use their spiny body as a fundamental holdfast. A basic performance analysis using live cystacanths of two representative species is also provided. METHODS: Adults of 13 Corynosoma spp. were obtained from 11 marine mammal species. Specimens were cut and carefully cleaned to examine muscle arrangement through light and scanning electron microscopy. Live cystacanths of C. australe and C. cetaceum were selected for performance analysis. Video records of evagination-invagination cycles of the proboscis were obtained and analysed with a video editor. RESULTS: The basic arrangement of proboscis retractors, trunk circular and longitudinal muscles, neck retractors and receptacle retractors, was conserved in all Corynosoma species. Interspecific variability was found in the relative development of disk muscles: minimum in C. enhydri, maximum in C. cetaceum; the distal insertion of the ventral neck retractor: ventro-lateral in C. cetaceum, C. hamannni and C. pseudohamanni and ventral in the other species; and the distal insertion of the receptacle retractors: more proximal in species with a longer hindtrunk. Performance analysis indicated striking similarities to that described for A. ranae except that (i) the foretrunk bends ventrally during the evagination-invagination cycles of the proboscis; (ii) disk muscles can flatten the tip of the foretrunk regardless of these cycles; and (iii) the receptacle bends ventrally and is driven to the hindtrunk by coordinated action of receptacle retractors. CONCLUSIONS: Species of Corynosoma are able to use up to six holfast mechanisms. Attachment relies on a similar performance to that described for A. ranae. However, structural ventral bending of an inflated, spiny foretrunk, with a parallel re-arrangement of foretrunk muscles, have generated unexpected novel functions that make attachment extremely effective in species of Corynosoma. Interspecific variability in trunk shape and muscle arrangement grossly correlates with the rheological conditions each species experiences in their microhabitats within the gut of marine mammals.


Assuntos
Acantocéfalos/anatomia & histologia , Acantocéfalos/fisiologia , Acantocéfalos/ultraestrutura , Animais , Feminino , Helmintíase Animal/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Masculino , Mamíferos/parasitologia , Microscopia Eletrônica de Varredura , Músculos/anatomia & histologia , Músculos/fisiologia , Músculos/ultraestrutura , Água do Mar/parasitologia , Gravação em Vídeo
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