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1.
Exp Parasitol ; 223: 108089, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33639135

RESUMO

The morphological, biological, and molecular characterisation of Cryptosporidium piscine genotype 7 from red-eye tetras (Moenkhausia sanctaefilomenae) are described, and the species name Cryptosporidium abrahamseni n. sp. is proposed. Histological analysis of intestinal tissue identified large numbers of Cryptosporidium organisms along the epithelial lining of the intestine. Sequence and phylogenetic analysis at 18S rRNA (18S) and actin loci conducted on intestinal scrapings revealed that C. abrahamseni n. sp. was genetically distinct from other Cryptosporidium species. At the 18S locus, it was most closely related to C. huwi (3.2% genetic distance) and exhibited genetic distances ranging from 5.9 to 6.5% (C. molnari) to 14.9% (C. scolpthalmi) from all other Cryptosporidium species. At the actin locus, the genetic distances were larger and C. abrahamseni n. sp. exhibited 10.3% genetic distance from C. huwi, and 17.6% (C. molnari) to 28% (C. canis) genetic distance from other Cryptosporidium spp. Phylogenetic analysis of concatenated 18S and actin sequences confirmed that C. abrahamseni n. sp. shares the closest genetic relationship with C. huwi (6.7% genetic distance), while the genetic distance between C. abrahamseni n. sp. and other Cryptosporidium spp. ranged from 12.1% (C. molnari) to 20.4% (C. canis). Based on genetic and histological data, C. abrahamseni n. sp. is validated as a separate species.


Assuntos
Characidae/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , Doenças dos Peixes/parasitologia , Enteropatias Parasitárias/veterinária , Actinas/genética , Animais , Evolução Biológica , Criptosporidiose/epidemiologia , Criptosporidiose/patologia , Cryptosporidium/genética , Cryptosporidium/ultraestrutura , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/patologia , Genótipo , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/patologia , Intestinos/parasitologia , Intestinos/patologia , Filogenia , Prevalência , RNA Ribossômico 18S/genética , Austrália Ocidental/epidemiologia
2.
J Parasitol ; 107(1): 1-15, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429430

RESUMO

The lecanicephalidean cestodes parasitizing the spiral intestine of the endangered giant freshwater whipray, Urogymnus polylepis (Bleeker), are investigated for the first time. Eight host specimens were collected between 2002 and 2008 at 2 collecting sites off the eastern coast of Borneo: 6 from the Kinabatangan River (Malaysia) and 2 from a fish market in Tarakan (Indonesia). Two of these individuals were found to be infected with a total of 3 new species of TetragonocephalumShipley and Hornell, 1905. Tetragonocephalum georgei n. sp. and Tetragonocephalum opimum n. sp. were recovered from a host specimen from the Kinabatangan River, and Tetragonocephalum levicorpum n. sp. was found parasitizing a host specimen purchased at a fish market in Tarakan. Specimens of each of the new species were prepared for light microscopy; specimens of 2 of the new species were prepared for scanning electron microscopy, and histological sections were prepared for 1 of the new species. The 3 new species are distinct from the 9 valid species of Tetragonocephalum and the 1 species inquirendum based on, for example, total length, number of proglottids and testes, and size of the scolex and acetabula. Tetragonocephalum georgei n. sp. and T. levicorpum n. sp. are unusual among their congeners in that they are euapolytic (i.e., gravid proglottids were not observed) rather than apolytic. They differ from one another in scolex and acetabula size. Tetragonocephalum opimum n. sp. is unusual among its congeners in its possession of vitelline follicles arranged in 2, rather than 3, regions in the proglottid. These new species increase the total number of valid species of Tetragonocephalum to 12 and the total number of known cestodes from U. polylepis to 13 species across 6 genera in 4 orders. This is the first account of lecanicephalideans reported from freshwater. The taxonomic status of each of the 32 nominal taxa historically associated with Tetragonocephalum is re-assessed. Type host identities of all valid species are revised and discussed in light of recent taxonomic efforts in the Dasyatidae Jordan and Gilbert.


Assuntos
Cestoides/isolamento & purificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Água Doce/parasitologia , Rajidae/parasitologia , Animais , Bornéu/epidemiologia , Cestoides/classificação , Cestoides/ultraestrutura , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Feminino , Doenças dos Peixes/epidemiologia , Indonésia/epidemiologia , Intestinos/parasitologia , Malásia/epidemiologia , Masculino , Microscopia Eletrônica de Varredura , Rios/parasitologia
3.
PLoS Pathog ; 16(12): e1009121, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351862

RESUMO

Parasitic helminths are sensed by the immune system via tissue-derived alarmins that promote the initiation of the appropriate type 2 immune responses. Here we establish the nuclear alarmin cytokine IL-33 as a non-redundant trigger of specifically IL-9-driven and mast cell-mediated immunity to the intestinal parasite Strongyloides ratti. Blockade of endogenous IL-33 using a helminth-derived IL-33 inhibitor elevated intestinal parasite burdens in the context of reduced mast cell activation while stabilization of endogenous IL-33 or application of recombinant IL-33 reciprocally reduced intestinal parasite burdens and increased mast cell activation. Using gene-deficient mice, we show that application of IL-33 triggered rapid mast cell-mediated expulsion of parasites directly in the intestine, independent of the adaptive immune system, basophils, eosinophils or Gr-1+ cells but dependent on functional IL-9 receptor and innate lymphoid cells (ILC). Thereby we connect the described axis of IL-33-mediated ILC2 expansion to the rapid initiation of IL-9-mediated and mast cell-driven intestinal anti-helminth immunity.


Assuntos
Interleucina-33/imunologia , Interleucina-9/imunologia , Enteropatias Parasitárias/imunologia , Linfócitos/imunologia , Mastócitos/imunologia , Estrongiloidíase/imunologia , Animais , Imunidade Inata/imunologia , Intestinos/imunologia , Intestinos/parasitologia , Camundongos , Strongyloides ratti/imunologia
4.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(6): 649-653, 2020 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-33325205

RESUMO

Human parasites may interact with the microbiome parasitizing in human and mammalian intestines. The interplay between intestinal parasites and gut microbiota and its potential impacts have been widely reported; however, some parasites that do not parasitize in intestines may also affect the characteristic of gut microbiota. Hereby, we review the advances in the research on the impacts of parasites inside and outside of human intestines on the gut microbiota.


Assuntos
Microbioma Gastrointestinal , Fatores Celulares Derivados do Hospedeiro , Enteropatias Parasitárias , Parasitos , Animais , Humanos , Intestinos/microbiologia , Intestinos/parasitologia
5.
J Parasitol ; 106(6): 809-817, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351948

RESUMO

Here we describe a new species of RhinebothriumLinton, 1890, from Hypanus guttatus (Bloch and Schneider). Rhinebothrium ramosi n. sp. can be differentiated from all 51 valid species of the genus by having 4-5 testes and uterus that extends throughout the entire length of the proglottid. Only 8 of the above species closely resemble R. ramosi in total length (Rhinebothrium bunburyense, Rhinebothrium chollaense, Rhinebothrium corbatai, Rhinebothrium dasyatidis, Rhinebothrium kruppi, Rhinebothrium lintoni, Rhinebothrium margaritense, and Rhinebothrium reydai). Despite the resemblance, R. bunburyense, R. corbatai, R. dasyatidis, R. lintoni, and R. margaritense can be distinguished from the new species by possessing a larger number of proglottids. The remaining 3 species (R. chollaense, R. kruppi, and R. reydai) overlap in total length and number of proglottids with R. ramosi. However, they can be distinguished from the new species by possessing a single posterior-most bothridial loculus instead of arranged as a pair, as found in the new species. This is the first report of the genus from the coastal waters of Brazil and brings to 52 the number of valid species for this genus. Additionally, we use the patterns of infection and distribution for species of Rhinebothrium to make predictions of expected diversity within the genus, especially for unsurveyed hosts in endemic marine ecoregions of the world.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Rajidae/parasitologia , Animais , Oceano Atlântico , Brasil/epidemiologia , Cestoides/isolamento & purificação , Cestoides/ultraestrutura , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Doenças dos Peixes/epidemiologia , Intestinos/parasitologia , Microscopia Eletrônica de Varredura/veterinária
6.
J Parasitol ; 106(6): 818-827, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351950

RESUMO

The cestode fauna of Squaliolus aliae was examined for the first time following the collection of elasmobranch specimens from Taiwan in 2005, 2013, and 2017. This small shark was found to host 2 tapeworm species. These consist of Acanthobothrium katherineae n. sp., which is new to science and is described herein, and a second species, in the genus Scyphophyllidium, which also appears to be new, but which is represented by insufficient material for formal description. Acanthobothrium katherineae is a category 5 species. It can be distinguished from 5 of the 19 other category 5 species in that it is apolytic, retaining proglottids on its strobila until they are gravid. This new species differs from the remaining 14 category 5 species in its combination of the following features: It is a smaller worm, has fewer than 100 proglottids, has a relatively short cephalic peduncle, and differs in bothridial size and loculus ratio. Sequence data for the D1-D3 region of the 28S rDNA gene were generated for one specimen of A. katherineae. This sequence, along with comparable sequence data for adults of 14 described and 2 undescribed species as well as specimens of 6 undescribed larval members of the genus, was included in a maximum likelihood phylogenetic analysis. The resulting tree places the shark-hosted A. katherineae within a clade of stingray-hosted species, with Acanthobothrium romanowi as its sister taxon. Acanthobothrium katherineae is 1 of only 19 Acanthobothrium species known to parasitize sharks. The tree resulting from this study, which is preliminary given the relatively poor taxon sampling of the diversity in the genus, included 3 of the shark-parasitizing Acanthobothrium species and suggests that all 3 represent host-switching events. This is the first report of an Acanthobothrium species from the family Dalatiidae and the first report of a Scyphophyllidium species from the order Squaliformes. These findings suggest that other members of the Squaliformes, many of which have not previously been examined for parasites, may host additional novel cestode taxa.


Assuntos
Cestoides/classificação , Infecções por Cestoides/veterinária , Doenças dos Peixes/parasitologia , Tubarões/parasitologia , Animais , Cestoides/genética , Cestoides/isolamento & purificação , Cestoides/ultraestrutura , Infecções por Cestoides/parasitologia , DNA de Helmintos/isolamento & purificação , Feminino , Intestinos/parasitologia , Masculino , Microscopia Eletrônica de Varredura/veterinária , Filogenia , Taiwan
7.
Nature ; 585(7826): 574-578, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939089

RESUMO

Epithelial organoids, such as those derived from stem cells of the intestine, have great potential for modelling tissue and disease biology1-4. However, the approaches that are used at present to derive these organoids in three-dimensional matrices5,6 result in stochastically developing tissues with a closed, cystic architecture that restricts lifespan and size, limits experimental manipulation and prohibits homeostasis. Here, by using tissue engineering and the intrinsic self-organization properties of cells, we induce intestinal stem cells to form tube-shaped epithelia with an accessible lumen and a similar spatial arrangement of crypt- and villus-like domains to that in vivo. When connected to an external pumping system, the mini-gut tubes are perfusable; this allows the continuous removal of dead cells to prolong tissue lifespan by several weeks, and also enables the tubes to be colonized with microorganisms for modelling host-microorganism interactions. The mini-intestines include rare, specialized cell types that are seldom found in conventional organoids. They retain key physiological hallmarks of the intestine and have a notable capacity to regenerate. Our concept for extrinsically guiding the self-organization of stem cells into functional organoids-on-a-chip is broadly applicable and will enable the attainment of more physiologically relevant organoid shapes, sizes and functions.


Assuntos
Homeostase , Intestinos/embriologia , Morfogênese , Organoides/embriologia , Tecidos Suporte , Animais , Padronização Corporal , Diferenciação Celular , Linhagem da Célula , Cryptosporidium parvum/patogenicidade , Células-Tronco Embrionárias Humanas/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Intestinos/citologia , Intestinos/parasitologia , Intestinos/patologia , Camundongos , Modelos Biológicos , Organoides/citologia , Organoides/parasitologia , Organoides/patologia , Regeneração , Medicina Regenerativa , Células-Tronco , Técnicas de Cultura de Tecidos/métodos , Engenharia Tecidual
8.
PLoS Negl Trop Dis ; 14(9): e0008619, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32966290

RESUMO

BACKGROUND: Despite the reported success in reducing morbidity, praziquantel alone is insufficient for the control and elimination of schistosomiasis, partly due to its poor efficacy against the juvenile worms. Artemisinin derivatives are effective against juvenile worms but are less effective against adult worms. We compared the safety and efficacy of praziquantel and Dihydroartemisinin-piperaquine combination against the standard praziquantel alone for treatment of intestinal schistosomiasis. METHODS: In this randomized, open-label, non-inferiority trial, 639 Schistosoma mansoni infected children were enrolled and randomized to receive either praziquantel alone or praziquantel plus Dihydroartemisinin-piperaquine combination. Two stool samples were collected on consecutive days at baseline, 3 and 8 weeks post-treatment and analyzed using thick smear Kato Katz method. Efficacy was assessed by cure and egg reduction rates at 3 and 8 weeks post-treatment. Adverse events were assessed within four hours of drugs intake. The primary outcome was cure rates at 8 weeks of post-treatment. Secondary outcomes were egg reduction rates at 8 weeks of post-treatment and treatment-associated adverse events. RESULTS: At 3 weeks of post-treatment, cure rates were 88.3% (263/298, 95% CI = 84.1%- 91.4%) and 81.2% (277/341, 95% CI = 76.7%- 85.0%) for the combination therapy and praziquantel alone, respectively (p < 0.01, odds ratio (OR) = 1.74, 95% CI of OR = 1.11 to 2.69). At 8 weeks, there was a significant drop in the cure rates in praziquantel alone group to 63.9% (218/341, 95% CI = 58.7%- 68.8%) compared to 81.9% (244/298, 95% CI = 77.1%- 85.8%) in the combination therapy group (p < 0.0001, OR = 2.55, 95%CI of OR = 1.75 to 3.69). Egg reduction rates at 8 weeks post-treatment were significantly higher in the combination therapy group 93.6% (95% CI = 90.8%- 96.4%) compared to 87.9% (95% CI = 84.4%- 91.4%) in the praziquantel only group (p = 0.01). On both Univariate and Multivariate regression analysis, type of treatment received was a significant predictor of cure at week 8 post-treatment. Overall, 30.8% (95% CI = 27.2%- 34.4%) of the study participants experienced mild and transient treatment-associated adverse events, post-treatment abdominal pain (27.1%) being the most common adverse event observed. There was no significant difference in the overall occurrence of adverse events between the two treatment groups. CONCLUSION: Praziquantel and Dihydroartemisinin piperaquine combination therapy is safe, and more efficacious compared to praziquantel alone for the treatment of intestinal schistosomiasis. Further studies are needed to explore if the combination therapy can be considered as an option for mass drug administration to control and eventually eliminate schistosomiasis.


Assuntos
Anti-Helmínticos/uso terapêutico , Artemisininas/uso terapêutico , Praziquantel/uso terapêutico , Quinolinas/uso terapêutico , Esquistossomose mansoni/tratamento farmacológico , Adolescente , Animais , Anti-Helmínticos/efeitos adversos , Artemisininas/efeitos adversos , Criança , Quimioterapia Combinada , Fezes/parasitologia , Feminino , Humanos , Intestinos/parasitologia , Masculino , Praziquantel/efeitos adversos , Quinolinas/efeitos adversos , Schistosoma mansoni/efeitos dos fármacos , Tanzânia , Resultado do Tratamento
9.
Salud(i)ciencia (Impresa) ; 24(3): 124-130, sept. 2020. tab.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1146404

RESUMO

Introduction: The decreasing prevalence of parasitosis from north to south in Argentina has led the scientific community to focus the epidemiological studies on the most vulnerable areas and, consequently, neglect the populations of Patagonia (South Argentina). The objectives of the present study were (i) to determine the prevalence of intestinal parasites in children and youth of Puerto Madryn (Chubut province, Patagonia), and (ii) to evaluate the parasitic infections found concerning socio-environmental factors and hygiene practices of the population. Materials and methods: Serial stool samples were processed using modified Ritchie and FLOTAC dual pellet techniques, and samples of anal swabs were examined by sedimentation. Socio-environmental variables and hygiene practices of the participants were surveyed using a semi-structured questionnaire. Results: Of all examined participants, 39.1% (68/174) were parasitized. A total of 6 parasite species were found and the most prevalent were Blastocystis sp (19.0%), Enterobius vermicularis (17.8%), and Giardia lamblia (6.3%). The risk of parasitosis and infection for Blastocystis sp was greater in participants who lived in houses without piped water (OR = 2.9 and OR = 3.2, respectively). The risk of infection for G. lamblia was positively associated with the lack of public waste collection service (OR = 5.6). Infection for E. vermicularis was higher in participants whose parents had a basic level of education (OR = 5.0). Conclusion: The parasitic infections observed reflect the environmental conditions of Patagonia and the need to focus studies on populations from peripheral areas to urban centers that are exposed to greater socio-economic vulnerability.


Introducción: La prevalencia de parasitosis decreciente de norte a sur en la Argentina, ha llevado a la comunidad científica a enfocar sus estudios epidemiológicos hacia las zonas más vulnerables y desatender a las poblaciones de la Patagonia (sur de Argentina). Los objetivos del presente estudio fueron: determinar la prevalencia de parásitos intestinales en niños y jóvenes de Puerto Madryn (Chubut, Patagonia), y evaluar las infecciones parasitarias en relación con los factores socioambientales y las prácticas de higiene de la población. Materiales y métodos: Se procesaron muestras seriadas de materia fecal mediante las técnicas Ritchie modificada y FLOTAC dual pellet, y muestras de escobillado anal por sedimentación. Se relevaron las variables socioambientales y las prácticas de higiene de los participantes mediante cuestionarios semiestructurados. Resultados: El 39.1% (68/174) de la población analizada estuvo parasitado. Se halló un total de 6 especies parásitas, las más prevalentes de las cuales fueron Blastocystis sp (19.0%), Enterobius vermicularis (17.8%) y Giardia lamblia (6.3%). El riesgo de parasitosis y de infección por Blastocystis sp fue mayor en los participantes que no poseían agua de red (odds ratio [OR] = 2.9 y OR = 3.2, respectivamente). La infección por G. lamblia se asoció de manera positiva con la falta de recolección pública de residuos (OR = 5.6). La infección por E. vermicularis fue superior en los participantes con padres que tenían un nivel de estudios primario (OR = 5.0). Conclusión: Las infecciones parasitarias observadas reflejan las condiciones ambientales de la Patagonia y la necesidad de orientar los estudios a poblaciones periféricas de los centros urbanos, las cuales están expuestas a mayor vulnerabilidad socioeconómica


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Parasitos , Argentina , Saneamento , Higiene , Giardia lamblia , Blastocystis , Educação , Enterobius , Intestinos/parasitologia
10.
Rev Bras Parasitol Vet ; 29(3): e009420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785526

RESUMO

The broad-headed spiny rat, Clyomys laticeps, is an echimyid rodent found in open areas of Cerrado and Pantanal biomes in central Brazil and Paraguay. Little is known about the parasites associated with this semi-fossorial species, as no previous studies have been conducted on their helminth fauna. The aim of this study was to report the helminth community structure of C. laticeps inhabiting Serra de Caldas Novas State Park, a Cerrado area in central Brazil. Trappings were carried out in dry grasslands from January to October 2016, and the large and small intestines of 14 C. laticeps individuals were examined for the presence of helminths. Three nematode species were found: Fuellebornema almeidai, Pterygodermatites (Paucipectines) sp., and Subulura forcipata, and 85.7% of the studied species were infected with at least one of these helminths. F. almeidai was the most prevalent species among hosts, and S. forcipata was the most abundant. This study is the first report on helminth community structure in C. laticeps. We report a new host species and increase the known geographical range of F. almeidai, and provide the first record of Pterygodermatites (Paucipectines) sp. infecting echimyids. This is also the first report of S. forcipata in a mammal host.


Assuntos
Helmintíase Animal , Helmintos , Roedores , Animais , Brasil , Ecossistema , Helmintíase Animal/parasitologia , Helmintos/classificação , Helmintos/fisiologia , Intestinos/parasitologia , Ratos , Roedores/parasitologia
11.
PLoS Negl Trop Dis ; 14(8): e0008600, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32853225

RESUMO

Helminth infections are among the World Health Organization's top neglected diseases with significant impact in many Less Economically Developed Countries. Despite no longer being endemic in Europe, the widespread presence of helminth eggs in archaeological deposits indicates that helminths represented a considerable burden in past European populations. Prevalence of infection is a key epidemiological feature that would influence the elimination of endemic intestinal helminths, for example, low prevalence rates may have made it easier to eliminate these infections in Europe without the use of modern anthelminthic drugs. To determine historical prevalence rates we analysed 589 grave samples from 7 European sites dated between 680 and 1700 CE, identifying two soil transmitted nematodes (Ascaris spp. and Trichuris trichiura) at all locations, and two food derived cestodes (Diphyllobothrium latum and Taenia spp.) at 4 sites. The rates of nematode infection in the medieval populations (1.5 to 25.6% for T. trichiura; 9.3-42.9% for Ascaris spp.) were comparable to those reported within modern endemically infected populations. There was some evidence of higher levels of nematode infection in younger individuals but not at all sites. The genetic diversity of T. trichiura ITS-1 in single graves was variable but much lower than with communal medieval latrine deposits. The prevalence of food derived cestodes was much lower (1.0-9.9%) than the prevalence of nematodes. Interestingly, sites that contained Taenia spp. eggs also contained D. latum which may reflect local culinary practices. These data demonstrate the importance of helminth infections in Medieval Europe and provide a baseline for studies on the epidemiology of infection in historical and modern contexts. Since the prevalence of medieval STH infections mirror those in modern endemic countries the factors affecting STH decline in Europe may also inform modern intervention campaigns.


Assuntos
Helmintíase/epidemiologia , Intestinos/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anti-Helmínticos/uso terapêutico , Ascaríase/epidemiologia , Ascaríase/transmissão , Ascaris , Criança , Pré-Escolar , Europa (Continente)/epidemiologia , Feminino , Variação Genética , Helmintíase/tratamento farmacológico , Helmintíase/transmissão , Helmintos/genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Doenças Negligenciadas/epidemiologia , Nematoides , Prevalência , Solo/parasitologia , Toaletes , Tricuríase/epidemiologia , Tricuríase/transmissão , Trichuris , Adulto Jovem
12.
Exp Parasitol ; 218: 107978, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32853633

RESUMO

One hundred and twenty one-day-old chukar partridges were randomly divided into eight groups which received diets with different supplementations. There were four unchallenged groups. One group received salinomycin (50 ppm), two groups received cinnamaldehyde (CINN) (100 and 200 mg/kg of diet), and another one received only the basal diet from the 1st to the 31st day. There were also four corresponding groups orally challenged by 3 × 105Eimeria kofoidi sporulated oocysts at the 21st day. Three samplings were done at the 24th, 26th, and 31st days of rearing for pathological and biochemical assessments. Fecal samples were daily taken to check the pattern of oocyst shedding from the 26th to 31st day. The body weight of birds was measured at 21st and 31st days. Along with the in vivo experiment, an in vitro sporulation inhibition test was carried out. The in vitro results showed that CINN decreased sporulation rate at 1 and 0.5 mg/ml. In vivo, it was found that CINN did not prevent the oocyst shedding. Furthermore, the histopathological findings revealed that CINN and salinomycin had no effect on infection establishment. However, our findings showed that CINN (200 mg/kg of diet) could enhance the body weight and improve antioxidant status. Although our results did not support the in vivo anticoccidial activity of CINN, it had a promising potential to improve antioxidant status and body weight in the chukar partridge.


Assuntos
Acroleína/análogos & derivados , Doenças das Aves/parasitologia , Coccidiose/veterinária , Eimeria/efeitos dos fármacos , Galliformes/parasitologia , Acroleína/farmacologia , Acroleína/uso terapêutico , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Doenças das Aves/tratamento farmacológico , Peso Corporal , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , Coccidiostáticos/farmacologia , Coccidiostáticos/uso terapêutico , Fezes/parasitologia , Galliformes/crescimento & desenvolvimento , Intestinos/parasitologia , Intestinos/patologia , Contagem de Ovos de Parasitas/veterinária , Piranos/farmacologia , Piranos/uso terapêutico , Distribuição Aleatória , Esporos de Protozoários/efeitos dos fármacos , Esporos de Protozoários/fisiologia , Ganho de Peso/efeitos dos fármacos
13.
Parasitol Res ; 119(9): 3053-3059, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32638102

RESUMO

Intestinal parasitic infections (IPIs) can be a severe threat to immunocompromised patients. This is particularly true for those undergoing chemotherapy and hemodialysis. The present research is aimed at identifying intestinal parasites that might be present in immunocompromised patients. In this cross-sectional study 1040 stool samples were collected from March to September 2017. Six hundred and forty-one stool samples from immunocompromised patients (279 samples from hemodialysis patients and 362 samples from chemotherapy patients) and 399 samples from the control group were collected in Guilan province, Iran. The samples were tested by direct, formalin-ether methods for protozoa and ova of intestinal parasites and Ziehl-Neelsen staining methods for coccidian parasites such as Cryptosporidium species. The overall parasitic infection rate was highest (15%) in hemodialysis patients and 11.3% in chemotherapy patients, whereas the lowest rate was observed (7.3%) in the control group. The infectivity rates were statistically significant (P = 0.008) when compared with the control group. The parasites found were Blastocystis hominis (8.9% of the cases), Entamoeba coli (1.6%), Iodamoeba butschlii (0.8%), Endolimax nana (0.6%), Chilomastix mesnili (0.5%), Strongyloides stercoralis (0.5%), and Taenia species (0.15%), whereas Giardia lamblia was detected only in the control group. There was not a correlation between prevalence of parasites with age or education levels of the infected individuals. Results of the present study suggest that periodic stool examinations in special parasitological laboratories should be included as part of routine and general medical care.


Assuntos
Infecção Hospitalar/parasitologia , Helmintíase/parasitologia , Helmintos/isolamento & purificação , Intestinos/parasitologia , Neoplasias/parasitologia , Parasitos/isolamento & purificação , Diálise Renal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos Transversais , Fezes/parasitologia , Feminino , Helmintíase/imunologia , Helmintos/classificação , Humanos , Hospedeiro Imunocomprometido , Enteropatias Parasitárias/parasitologia , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Parasitos/classificação , Parasitos/genética , Prevalência , Adulto Jovem
14.
Exp Parasitol ; 216: 107945, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32615133

RESUMO

Despite decades of investigation to clarify protective mechanisms of anticoccidial responses, one crucial field is neglected, that is, protective memory responses in primed birds. Protective memory immunity is critical for host resistance to reinfection and is the basis of modern vaccinology, especially in developing successful subunit vaccines. There are important differences between the immune responses induced by infections and antigens delivered either as killed, recombinant proteins or as live, replicating vector vaccines or as DNA vaccines. Animals immunized with these vaccines may fail to develop protective memory immunity, and is still naïve to Eimeria infection. This may explain why limited success is achieved in developing next-generation anticoccidial vaccines. In this review, we try to decipher the protective memory responses against Eimeria infection, assess immune responses elicited by various anticoccidial vaccine candidates, and propose possible approaches to develop rational vaccines that can induce a protective memory response to chicken coccidiosis.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/imunologia , Memória Imunológica/fisiologia , Doenças das Aves Domésticas/imunologia , Vacinas Protozoárias , Animais , Galinhas/imunologia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Intestinos/imunologia , Intestinos/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Recidiva , Vacinação/veterinária , Vacinas de Subunidades/imunologia
15.
Parasitol Res ; 119(10): 3221-3231, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32671541

RESUMO

Members of the genus Lueheia Travassos, 1919, are endoparasites of birds, particularly passerines, throughout the Americas. Adults of Lueheia sp., (Plagiorhynchidae Golvan, 1960; Porrorchinae Golvan, 1956) were recovered from the intestine of the American robin (Turdus migratorius phillipsi Bangs) in Mexico City, and two other species of acanthocephalans identified as Porrorchis nickoli, (Plagiorhynchidae: Porrorchinae) Salgado-Maldonado and Cruz-Reyes, 2002 and Centrorhynchus microcephalus (Bravo-Hollis, 1947) Golvan, 1956 (Centrorhynchidae Van Cleave, 1916), were recovered from the Virginia opossum (Didelphis virginiana Allen) and groove-billed ani (Crotophaga sulcirostris Swainson), respectively in southeastern Mexico. Specimens of three species were sequenced at two molecular markers, the small subunit (SSU) and large subunit (LSU) of the nuclear rDNA and compared with other sequences available in GenBank. Maximum likelihood and Bayesian inference analyses of the combined (LSU + SSU) dataset and each individual dataset revealed that the specimens of Lueheia sp. formed an independent lineage, which is recognized herein as a new species, Lueheia aztecae n. sp., representing the fifth species of the genus in the Americas, and the second in the Nearctic region. The new species can be morphologically distinguished from the other five species in the genus by having a cylindrical proboscis, armed with 24-26 longitudinal rows with 9-10 hooks each. Phylogenetic inference performed with the combined dataset consisting of two genes (LSU + SSU) revealed that Lueheia aztecae n. sp. and P. nickoli belonging to subfamily Porrorchinae, formed two independent lineages, indicating that the subfamily is paraphyletic. Porrorchis nickoli and C. microcephalus formed a clade with other species of the genus Centrorhynchus, suggesting that P. nickoli should be transferred to genus Centrorhynchus, to form C. nickoli n. comb. In addition, we briefly discuss the ecological associations between the members of the families Plagiorhynchidae and Centrorhynchidae.


Assuntos
Acantocéfalos/anatomia & histologia , Acantocéfalos/classificação , Helmintíase Animal/parasitologia , Aves Canoras/parasitologia , Acantocéfalos/genética , Animais , Sequência de Bases , Teorema de Bayes , DNA Ribossômico/genética , Marcadores Genéticos/genética , Intestinos/parasitologia , México , Filogenia
16.
Parasitol Res ; 119(7): 2237-2244, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451718

RESUMO

Ecological data on marine mammal parasites represent an excellent opportunity to expand our understanding of host-parasite systems. In this study, we used a dataset of intestinal helminth parasites on 167 long-finned pilot whales Globicephala melas (Traill, 1809) from seven localities in the Faroe Islands to evaluate the extent to which the host's age and sex influence the occurrence, richness, and nested pattern of helminth parasites and the importance of individual hosts to the helminth community. We found positive effects of age on both the occurrence and richness of helminths. Older host individuals showed an ordered accumulation of parasites, as evidenced by the nested pattern in their composition. Males had a higher occurrence of parasites than females, but the richness of helminths did not differ between sexes. Our findings suggest that differences in host-parasite interactions in long-finned pilot whales result mainly from age-structured variations in biological and behavioral characteristics.


Assuntos
Helmintíase/epidemiologia , Helmintos/isolamento & purificação , Interações Hospedeiro-Parasita/fisiologia , Baleias Piloto/parasitologia , Distribuição por Idade , Fatores Etários , Animais , Dinamarca/epidemiologia , Feminino , Humanos , Intestinos/parasitologia , Masculino , Fatores Sexuais
17.
BMC Infect Dis ; 20(1): 379, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460777

RESUMO

BACKGROUND: Intestinal parasitic infections (IPIs) and anaemia are major health problems. This study assessed the prevalence of intestinal parasitic infections, anaemia and associated factors among pre-school children in rural areas of the Tigray region, northern Ethiopia. METHODS: A community based cross-sectional study was conducted among 610 pre-school children in rural communities of Northern Ethiopia from June 2017 to August 2017. Stool specimens were examined for the presence of trophozoites, cysts, oocysts, and ova using direct, formal-ethyl acetate concentration, Kato-Katz, and Ziehl-Neelsen techniques. Haemoglobin was measured using a HemoCue spectrometer. RESULTS: Among the 610 participating pre-school children in the study, the prevalence of IPIs and anaemia were 58% (95% conference interval (CI): 54.1-61.9%) and 21.6% (95% CI: 18.5-25.1%), respectively. Single, double, and triple parasitic infections were seen in 249 (41, 95% CI: 37-45%), 83 (14, 95% CI: 11-17%), and 22 (3.6, 95% CI: 2.4-5.4%) children, respectively. Of the seven intestinal parasitic organisms recorded from the participants, Entamoeba histolytica/dispar was the most prevalent 220 (36.1%) followed by Giardia lamblia 128 (20.1%), and Hymenolepis nana 102 (16.7%). Mixed infections were common among G. lamblia, E. histolytica/dispar and Cryptosporidium spp. oocyst. Intestinal parasitic infection prevalence increased from 47% in children aged 6-11 months to 66% in those aged 48-59 months; the prevalence ratio (PR) associated with a one-year increase in age was 1.08 (95% CI: 1.02-1.14, p = 0.009). Age-adjusted prevalence was higher in children who had been dewormed (PR = 1.2; 95% CI: 1.00-1.4, p = 0.045), and lower in households having two or more children aged under five (PR = 0.76, 95% CI: 0.61-0.95, p = 0.015). Anaemia rose from 28% in children aged 6-11 months to 43% in those aged 12-23 months, then fell continuously with age, reaching 7% in those aged 48-59 months. Age adjusted, anaemia was more prevalent in households using proper disposal of solid waste (PR = 1.5, 95% CI: 0.1-2.10, p = 0.009) while eating raw meat (PR = 0.49, 95% CI: 0.45-0.54, p = 0.000), any maternal education (PR = 0.64 95% CI: 0.52-0.79, p = 0.000), and household water treatment (PR = 0.75, 95% CI: 0.56-1.0, p = 0.044) were associated with lower prevalence of anaemia. CONCLUSIONS: More than half of the children were infected with intestinal parasites, while anaemia prevalence was concentrated in the 12-23 month age group. This study has identified a number of potentially modifiable risk factors to address the significant prevalence of IPIs and anaemia in these children. Improvements in sanitation, clean water, hand hygiene, maternal education could address both short and long-term consequences of these conditions in this vulnerable population.


Assuntos
Anemia/epidemiologia , Enteropatias Parasitárias/epidemiologia , Anemia/parasitologia , Animais , Criança , Pré-Escolar , Estudos Transversais , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Entamoeba histolytica/genética , Entamoeba histolytica/isolamento & purificação , Etiópia/epidemiologia , Fezes/parasitologia , Feminino , Giardia lamblia/genética , Giardia lamblia/isolamento & purificação , Higiene das Mãos , Humanos , Hymenolepis nana/genética , Hymenolepis nana/isolamento & purificação , Lactente , Enteropatias Parasitárias/parasitologia , Intestinos/parasitologia , Masculino , Prevalência , Fatores de Risco , População Rural/estatística & dados numéricos , Saneamento
18.
Parasit Vectors ; 13(1): 200, 2020 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-32306993

RESUMO

BACKGROUND: Approximately 30% of children worldwide are infected with gastrointestinal parasites. Depending on the species, parasites can disrupt intestinal bacterial microbiota affecting essential vitamin biosynthesis. METHODS: Stool samples were collected from 37 asymptomatic children from a previous cross-sectional Argentinian study. A multi-parallel real-time quantitative PCR was implemented for Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, Cryptosporidium spp., Entamoeba histolytica and Giardia duodenalis. In addition, whole-genome sequencing analysis was conducted for bacterial microbiota on all samples and analyzed using Livermore Metagenomic Analysis Toolkit and DIAMOND software. Separate analyses were carried out for uninfected, Giardia-only, Giardia + helminth co-infections, and helminth-only groups. RESULTS: For Giardia-only infected children compared to uninfected children, DNA sequencing data showed a decrease in microbiota biodiversity that correlated with increasing Giardia burden and was statistically significant using Shannon's alpha diversity (Giardia-only > 1 fg/µl 2.346; non-infected group 3.253, P = 0.0317). An increase in diversity was observed for helminth-only infections with a decrease in diversity for Giardia + helminth co-infections (P = 0.00178). In Giardia-only infections, microbiome taxonomy changed from Firmicutes towards increasing proportions of Prevotella, with the degree of change related to the intensity of infection compared to uninfected (P = 0.0317). The abundance of Prevotella bacteria was decreased in the helminths-only group but increased for Giardia + helminth co-infections (P = 0.0262). Metagenomic analysis determined cobalamin synthesis was decreased in the Giardia > 1 fg/µl group compared to both the Giardia < 1 fg/µl and the uninfected group (P = 0.0369). Giardia + helminth group also had a decrease in cobalamin CbiM genes from helminth-only infections (P = 0.000754). CONCLUSION: The study results may provide evidence for an effect of parasitic infections enabling the permissive growth of anaerobic bacteria such as Prevotella, suggesting an altered capacity of vitamin B12 (cobalamin) biosynthesis and potential impact on growth and development in children .


Assuntos
Coinfecção , Microbioma Gastrointestinal/genética , Intestinos , Parasitos/genética , Vitamina B 12/genética , Animais , Criança , Pré-Escolar , Coinfecção/microbiologia , Coinfecção/parasitologia , Estudos Transversais , DNA de Helmintos , DNA de Protozoário , Feminino , Genes Bacterianos , Giardia lamblia/classificação , Giardia lamblia/genética , Giardia lamblia/isolamento & purificação , Helmintos/classificação , Helmintos/genética , Helmintos/isolamento & purificação , Humanos , Intestinos/microbiologia , Intestinos/parasitologia , Masculino , Metagenômica , Parasitos/classificação , Parasitos/isolamento & purificação , Projetos Piloto , Reação em Cadeia da Polimerase em Tempo Real , Vitamina B 12/metabolismo , Sequenciamento Completo do Genoma
19.
BMC Evol Biol ; 20(1): 43, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32299345

RESUMO

BACKGROUND: Parasites may mediate the success of biological invasions through their effect on host fitness and thus, on host population growth and stability. However, a release from the pressure of parasites is strongly related to the genetic differentiation of the host. In invasive host populations, the number of available genetic variants, allowing them to 'fight' the infection, are likely to be influenced by founder events and genetic drift. The level standing genetic variation of invasive populations may be crucial in successfully adapting to new environments and resisting diseases. We studied invasive populations of raccoon that experienced a random reduction in genetic diversity during the establishment and evaluated the relationship between host immune genetic diversity and intestinal parasites infection. RESULTS: We distinguished two different genetic clusters that are characterized by different sets of functionally relevant MHC-DRB alleles. Both clusters were characterized by considerably different allele-parasite associations and different levels of parasite infection. The specific resistance MHC-DRB alleles explained the lower prevalence of Digenea parasites. An increased infection intensity was related to the presence of two MHC-DRB alleles. One of these alleles significantly decreased in frequency over time, causing a decrease of Digenea abundance in raccoons in consecutive years. CONCLUSIONS: Our findings suggest that intestinal parasites can exert selective pressure on an invasive host with lowered levels of immune genetic diversity and contribute to promoting local adaptation over time. The random genetic drift that created the two different genetic clusters in the invasive raccoon range imposed completely different MHC-parasite associations, strongly associated with the infection status of populations. Our findings underline the role of standing genetic variation in shaping host-parasite relationships and provide empirical support that functional genetic variation may be, at least partly, responsible for differences in the success of invasive populations.


Assuntos
Variação Genética , Interações Hospedeiro-Parasita , Espécies Introduzidas , Guaxinins/genética , Guaxinins/imunologia , Alelos , Animais , Interações Hospedeiro-Parasita/imunologia , Intestinos/parasitologia , Família Multigênica , Parasitos/fisiologia , Seleção Genética
20.
Parasit Vectors ; 13(1): 186, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272968

RESUMO

BACKGROUND: From a veterinary-medical point of view, the stable fly, Stomoxys calcitrans, is perhaps the economically most important blood-sucking muscoid fly species (Diptera: Muscidae), owing to its worldwide occurrence, frequently high local abundance, direct harm caused to livestock, pet animals and humans, as well as its vector role. Considering the latter in the context of protozoan parasites, the stable fly is a mechanical vector of trypanosomes and Besnoitia besnoiti. However, its role as a vector of piroplasms appears to be seldom studied, despite old data suggesting mechanical transmission of babesiae by dipteran flies. METHODS: In this study 395 stable flies (and one Haematobia stimulans) were collected at a cattle farm with known history of bovine theileriosis, and at further nine, randomly chosen locations in Hungary. These flies were separated according to sex (30 of them also cut into two parts: the head with mouthparts and the thorax-abdomen), followed by individual DNA extraction, then screening for piroplasms by PCR and sequencing. RESULTS: In stable flies, Theileria orientalis and T. capreoli were identified at the cattle farm and T. equi was identified in three other locations. At the cattle farm, significantly more male stable flies carried piroplasm DNA than females. There was no significant difference between the ratio of PCR-positive flies between the stable (void of cattle for at least two hours) and the pen on the pasture with cattle at the time of sampling. Among dissected flies (29 S. calcitrans and 1 H. stimulans), exclusively the thoracic-abdominal parts were PCR-positive, whereas the head and mouthparts remained negative. CONCLUSIONS: Theileria DNA is detectable in stable flies, in the case of T. orientalis at least for two hours after blood-feeding, and in the case of T. capreoli also in the absence of infected hosts (i.e. roe deer). Male flies rather than females, and thoracic-abdominal (most likely crop) contents rather than mouthparts may pose a risk of mechanical transmission. These data suggest that it is worth to study further the vector role of stable flies in the epidemiology of theilerioses, in which not the immediate, but rather the delayed type transmission seems possible.


Assuntos
Insetos Vetores/parasitologia , Muscidae/parasitologia , Theileria/isolamento & purificação , Theileriose/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , DNA de Protozoário , Cervos/parasitologia , Feminino , Hungria , Intestinos/parasitologia , Masculino , Patologia Molecular/métodos , RNA Ribossômico 18S
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