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1.
Med Vet Entomol ; 33(4): 530-535, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31280502

RESUMO

Hippobosca longipennis (Diptera: Hippoboscidae), the dog fly or dog louse fly, is an obligate blood-feeding ectoparasite of wild and domestic carnivores in Africa and the Middle East. Outside its typically known geographic range, H. longipennis has been reported occasionally on mainly domestic dogs in Asia and southern Europe, and infrequently in other areas (central Europe and the U.S.A.). This paper presents the first report of H. longipennis in Romania and the second record of Lipoptena fortisetosa (Diptera: Hippoboscidae), a potentially invasive species. Hippobosca longipennis was found on domestic dogs in two regions of the country (northern Romania in Maramures and southwestern Romania in Dobrogea) and on two road-killed wildcats in Maramures. Lipoptena fortisetosa was found on domestic dogs in Maramures. In both species identification was based on morphology and confirmed by barcoding of the cytochrome c oxidase subunit 1 gene. It is not clear for how long H. longipennis has been present in central Europe, nor if it was introduced (via the movement of domestic dogs or import of exotic carnivores) or present historically (Holocene remnants). This paper discusses the possible origins of H. longipennis in central Europe as its current distribution in the area is sparse and patchy.


Assuntos
Distribuição Animal , Dípteros/fisiologia , Doenças do Cão/parasitologia , Ectoparasitoses/veterinária , Animais , Cães , Ectoparasitoses/parasitologia
2.
BMC Evol Biol ; 19(1): 69, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832573

RESUMO

BACKGROUND: Spiny mice of the genus Acomys are distributed mainly in dry open habitats in Africa and the Middle East, and they are widely used as model taxa for various biological disciplines (e.g. ecology, physiology and evolutionary biology). Despite their importance, large distribution and abundance in local communities, the phylogeny and the species limits in the genus are poorly resolved, and this is especially true for sub-Saharan taxa. The main aims of this study are (1) to reconstruct phylogenetic relationships of Acomys based on the largest available multilocus dataset (700 genotyped individuals from 282 localities), (2) to identify the main biogeographical divides in the distribution of Acomys diversity in dry open habitats in Afro-Arabia, (3) to reconstruct the historical biogeography of the genus, and finally (4) to estimate the species richness of the genus by application of the phylogenetic species concept. RESULTS: The multilocus phylogeny based on four genetic markers shows presence of five major groups of Acomys called here subspinosus, spinosissimus, russatus, wilsoni and cahirinus groups. Three of these major groups (spinosissimus, wilsoni and cahirinus) are further sub-structured to phylogenetic lineages with predominantly parapatric distributions. Combination of alternative species delimitation methods suggests the existence of 26 molecular operational taxonomic units (MOTUs), potentially corresponding to separate species. The highest genetic diversity was found in Eastern Africa. The origin of the genus Acomys is dated to late Miocene (ca. 8.7 Ma), when the first split occurred between spiny mice of eastern (Somali-Masai) and south-eastern (Zambezian) savannas. Further diversification, mostly in Plio-Pleistocene, and the current distribution of Acomys were influenced by the interplay of global climatic factors (e.g., Messinian salinity crisis, intensification of Northern Hemisphere glaciation) with local geomorphology (mountain chains, aridity belts, water bodies). Combination of divergence dating, species distribution modelling and historical biogeography analysis suggests repeated "out-of-East-Africa" dispersal events into western Africa, the Mediterranean region and Arabia. CONCLUSIONS: The genus Acomys is very suitable model for historical phylogeographic and biogeographic reconstructions of dry non-forested environments in Afro-Arabia. We provide the most thorough phylogenetic reconstruction of the genus and identify major factors that influenced its evolutionary history since the late Miocene. We also highlight the urgent need of integrative taxonomic revision of east African taxa.


Assuntos
Ecossistema , Murinae/genética , Filogeografia , África , África Oriental , África do Norte , África Ocidental , Animais , Arábia , Evolução Biológica , DNA Mitocondrial/química , DNA Mitocondrial/genética , Oriente Médio , Murinae/classificação , Filogenia
3.
Med Vet Entomol ; 29(4): 444-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26211924

RESUMO

Trypanosomes are known as widespread blood parasites of birds; however, knowledge of their prevalences in vectors and their overall biodiversity is rather limited. To assess the prevalences in potential vectors, we have microscopically examined ornithophilic bloodsucking Diptera (Culicidae, Simuliidae and Hippoboscidae) for the presence of trypanosomatids in their guts. In total, 3270 specimens were dissected, namely Culex pipiens Linnaeus, 1758 (n = 898), C. modestus Ficalbi, 1890 (136), Simulium vernum (Macquart, 1838) (1455), S. angustipes Edwards, 1915 (221) and Ornithomyia avicularia (Linnaeus, 1758) (560). All insect species were found to be infected with trypanosomatids, and the prevalence ranged from 4 to 8% but reached 60% in S. vernum. Blackflies and hippoboscids exclusively harboured trypanosomes (both T. cf. avium s.s. Danilewsky, 1885; T. corvi/culicavium group in hippoboscids). Mosquitoes were infected with T. culicavium Votypka, 2012 and T. avium s. l. but also with monoxenous parasites, namely Crithidia brevicula Frolov and Malysheva, 1989, and Paratrypanosoma confusum Votypka and Lukes, 2013. Only 4% of the isolated parasite strains were monoxenous whereas the majority were avian trypanosomes, confirming the vectorial status of the studied insects.


Assuntos
Dípteros/parasitologia , Insetos Vetores/parasitologia , Trypanosomatina/isolamento & purificação , Animais , Culicidae/parasitologia , República Tcheca , Aves Predatórias/parasitologia , Simuliidae/parasitologia
4.
Med Vet Entomol ; 29(4): 355-60, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26171684

RESUMO

Phlebotomine sandflies, vectors of Leishmania (Kinetoplastida: Trypanosomatidae) parasites that affect millions of people worldwide, breed in terrestrial biotopes. As immature stages are rarely accessible, the detection of their natural breeding sites is primarily based on findings of juvenile males with unrotated external genitalia. In males, permanent 180° rotation on the longitudinal body axis occurs soon after eclosion; however, no study has as yet addressed this aspect in detail. The present study describes the timing and duration of the rotation of male external genitalia in eight highly medically important sandfly species belonging to the genera Sergentomyia, Lutzomyia and Phlebotomus (all: Diptera: Psychodidae), kept under controlled laboratory conditions. The average duration of rotation was species-specific and varied from 12 h in Sergentomyia schwetzi to 33 h in Phlebotomus sergenti. Significant differences in rotation times were found among species, even between two closely related species of the subgenus Larroussius, Phlebotomus orientalis and Phlebotomus tobbi. The rotation of genitalia in all three studied genera was randomly oriented and similar numbers of clockwise and counter-clockwise events were observed. The study also addresses the effects of some external factors. In all species studied, rotation was not affected by the time of day of eclosion. Similarly, no differences in total rotation time were found between Phlebotomus papatasi males maintained at 25 and 20 °C, respectively. The present findings will assist in the search for natural breeding sites and in studies aimed at elucidating strategies for integrated sandfly and leishmaniasis control.


Assuntos
Psychodidae/crescimento & desenvolvimento , Animais , Genitália Masculina/anatomia & histologia , Genitália Masculina/crescimento & desenvolvimento , Masculino , Phlebotomus/anatomia & histologia , Phlebotomus/crescimento & desenvolvimento , Psychodidae/anatomia & histologia , Pupa/anatomia & histologia , Pupa/crescimento & desenvolvimento
5.
Bratisl Lek Listy ; 116(3): 203-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25869571

RESUMO

We present a case of imported leishmaniasis in a 31-year-old woman from Slovakia, who visited the countries of South America for three months in 2011. On 29 and 31 August 2011, she was probably infected with Leishmania parasites in the jungles of Ecuador. Approximately one week after returning to Slovakia, a small papules appeared on patient's left leg. Another wound was found after two weeks. Both ulcers were enlarging. We proved amastigote forms of Leishmania spp. only in repeated dermal scrapings from the edge of the ulcer by Giemsa staining after negative results from examination of a wound scrape and biopsy specimen. We identified the species Leishmania (Viannia) panamensis as a causative agent by using the polymerase chain reaction (PCR) method and subsequent sequencing of the ITS region. Closure of wounds and scab formation were observed after 20 days of treatment with sodium stibogluconate. In the control microscopic examination after the end of the treatment, parasites were not present, and the PCR confirmed the negative result (Fig. 2, Ref. 31).


Assuntos
Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Úlcera Cutânea/parasitologia , Viagem , Adulto , Animais , Gluconato de Antimônio e Sódio/uso terapêutico , Antiprotozoários/uso terapêutico , Transmissão de Doença Infecciosa , Equador , Feminino , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Reação em Cadeia da Polimerase , Eslováquia , Resultado do Tratamento , Cicatrização
6.
J Med Entomol ; 50(5): 955-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24180098

RESUMO

The spread of leishmaniasis to areas where it was previously considered nonendemic has been recently found in the New and Old Worlds, and climate changes are suspected as a crucial factor responsible for this spread. Ambient temperature is known to significantly affect the metabolism of sand flies and their developmental times, but little is known about the effect of temperature on the Leishmania life cycle in vectors. This study assesses the effect of temperature on the development of two closely related New World Viannia species, Leishmania braziliensis and Leishmania peruviana, in the permissive vector Lutzomyia longipalpis, and on the development of New and Old World Leishmania infantum in its natural vectors Lu. longipalpis and Phlebotomus perniciosus, respectively. The mountain species L. peruviana developed well in sand fly females kept at 20 degrees C, whereas at 26 degrees C, most infections were lost during the defecation ofbloodmeal remains; this suggests an adaptation to the slower metabolism of sand flies living at lower ambient temperature. On the contrary, L. infantum and L. braziliensis developed well at both temperatures tested; heavy late-stage infections were observed in a majority of sand fly females maintained at 20 degrees C as well 26 degrees C. Frequent fully developed infections of L. infantum and L. braziliensis at 20 degrees C suggest a certain risk of the spread of these two Leishmania species to higher latitudes and altitudes.


Assuntos
Leishmania/fisiologia , Psychodidae/parasitologia , Animais , Mudança Climática , Feminino , Leishmania/crescimento & desenvolvimento , Leishmania braziliensis/crescimento & desenvolvimento , Leishmania braziliensis/fisiologia , Leishmania infantum/crescimento & desenvolvimento , Leishmania infantum/fisiologia , Phlebotomus/parasitologia , Especificidade da Espécie , Temperatura
7.
Parasitol Res ; 112(4): 1667-77, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23385972

RESUMO

We studied haemosporidian parasites in the scarlet rosefinch Carpodacus erythrinus in a small isolated semicolony during an eight-year period using molecular methods of parasite detection. The scarlet rosefinch is an interesting model of parasite host species. It winters in South Asia which represents a rare exception among European passerines. Males express yellow to red carotenoid-based plumage ornament which is a good predictor of male reproductive success. In 240 blood samples originating from 199 adult individuals, the total parasite prevalence reached 60%. Prevalence varied among years from 36 to 81% in Haemoproteus, 8 to 22% in Plasmodium, and 0 to 14% in Leucocytozoon. Twenty parasite lineages were detected (Haemoproteus: 5 lineages, Plasmodium: 10 lineages, and Leucocytozoon: 5 lineages). Among them, the Haemoproteus ROFI2 lineage, which is a host-specific parasite lineage of the scarlet rosefinch, was the most frequently found. Parasite lineages showed varying degree of lineage specificity. While Haemoproteus lineages detected in the scarlet rosefinch have relatively narrow host breadth restricted mainly to Fringillidae family, Leucocytozoon and Plasmodium lineages generally showed wider host range. The presence of some parasite lineages hitherto detected in sedentary European passerines (SISKIN1, CCF3, BT2) or in Culicoides biting midges at the same locality (ROFI1) suggest local transmission. On the contrary, lineages LK05 and FANTAIL1 that were previously reported exclusively from Asian hosts imply parasite transmission at the scarlet rosefinch wintering sites in South Asia. Mixed infections were found in 17% of infected samples and comprised mainly the most frequent lineages. The pattern of concomitant infections seemed to be rather random and matched expected levels based on lineage frequencies. Between-year comparisons revealed that in a majority of the repeatedly captured individual hosts the infection status remained unchanged (individuals stayed uninfected or possessed the same parasite lineages). However, 16 gains and 8 losses of lineages were also reported. We have not found any effect of haemosporidians on male carotenoid ornament expression or host body mass.


Assuntos
Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Ásia , Sangue/parasitologia , Coinfecção/epidemiologia , Coinfecção/parasitologia , Coinfecção/veterinária , Europa (Continente) , Masculino , Passeriformes , Prevalência
8.
Microbes Infect ; 13(7): 691-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21382502

RESUMO

Since 2005, an outbreak of human cutaneous leishmaniasis (CL) in Ghardaïa, south Algeria, was studied and one output of these investigations was the identification of two Leishmania species, Leishmania major and Leishmania killicki, as the CL causative agents. In the present study, we were curious to focus on sand fly fauna present in this area and detection of Leishmania-positive sand fly females. Sand flies (3717) were collected during two seasons using sticky papers and CDC light traps in urban, rural and sylvatic sites. Twelve Phlebotomus species were identified. Phlebotomus papatasi was dominant in the urban site while Phlebotomus sergenti and Phlebotomus riouxi/chabaudi were dominant in the sylvatic site. Out of 74 P. sergenti females captured by CDC light traps in the sylvatic site populated by Ghardaïas' Gundi (Massoutiera mzabi), three ones were hosting Leishmania promastigotes. PCR-RFLP and sequencing of seven single-copy coding DNA sequences identified the promastigotes as L. killicki. Furthermore, laboratory experiments revealed that L. killicki isolate sampled from a CL patient inhabiting the studied region develop well in P. sergenti females. Our findings strongly suggest that the human cutaneous leishmaniases caused by L. killicki is a zoonotic disease with P. sergenti sand flies acting as hosts and vectors and gundi rodents as reservoirs.


Assuntos
Interações Hospedeiro-Parasita , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/transmissão , Phlebotomus/parasitologia , Argélia/epidemiologia , Animais , DNA de Protozoário/genética , Surtos de Doenças , Feminino , Humanos , Insetos Vetores/classificação , Insetos Vetores/parasitologia , Leishmania/classificação , Leishmania/genética , Leishmania/isolamento & purificação , Masculino , Phlebotomus/classificação , Polimorfismo de Fragmento de Restrição , Roedores/parasitologia , Estações do Ano , Análise de Sequência de DNA , População Urbana
9.
J Vector Ecol ; 36 Suppl 1: S49-57, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21366780

RESUMO

An intraspecific study of Phlebotomus sergenti was performed on populations from Turkey, Syria, Israel, and Uzbekistan by four different approaches: geometric morphometrics, RAPD analysis, internal transcribed spacer 2 (ITS2) sequencing (nuclear marker), and cytochrome B sequencing (mitochondrial marker). In RAPD analysis, distinct clades were formed in accordance with the geographical origin of the specimens. There was no distinct grouping according to place of origin within the Turkish samples from various localities in south-eastern Anatolia, which suggests a gene flow between populations separated spatially by the Amanos mountains, a mountain range of a considerable altitude. The results of ITS2 rDNA sequencing complied with the previously published intraspecific division of P. sergenti into two branches, northeastern and southwestern. However, mtDNA haplotypes formed three lineages with specimens from Turkey and Israel, sharing a common clade. A previously postulated hypothesis about a complex of sibling species within P. sergenti is therefore questionable. Cytochrome B seems to be a more discriminative marker for intraspecific variability assessment.


Assuntos
Insetos Vetores/classificação , Insetos Vetores/genética , Leishmania tropica/patogenicidade , Phlebotomus/classificação , Phlebotomus/genética , Animais , Citocromos b/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Variação Genética/genética , Haplótipos/genética , Israel , Phlebotomus/parasitologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Síria , Turquia , Uzbequistão
10.
Med Vet Entomol ; 25(1): 104-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20497315

RESUMO

The section of habitat used by particular bloodsucking insects when seeking bloodmeals may influence the spectrum of hosts to which they have access and consequently the diseases they transmit. The vertical distribution of ornithophilic bloodsucking Diptera (Culicidae, Simuliidae and Ceratopogonidae) was studied using bird-baited traps set at both ground and tree canopy levels. In total, 1240 mosquito females of eight species, 1201 biting midge females of 11 species, and 218 blackfly females of two species were captured during 2003-2005. Culex pipiens (L.) (Diptera: Culicidae) was found to prefer ground-level habitats, whereas Anopheles plumbeus (Stephens) (Diptera: Culicidae), biting midges [Culicoides spp. (Diptera: Ceratopogonidae)] and Eusimulium angustipes (Edwards) (Diptera: Simuliidae) preferred the canopy. The results of this study with regard to Cx. pipiens behaviour differ from those of most previous studies and may indicate different spatial feeding preferences in geographically separate populations. The occurrence of E. angustipes in the canopy is concordant with its role in the transmission of avian trypanosomes. These findings may be important for surveillance programmes focusing on ornithophilic Diptera which transmit various pathogenic agents.


Assuntos
Ceratopogonidae/fisiologia , Culicidae/fisiologia , Simuliidae/fisiologia , Animais , Comportamento Animal , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Aves/parasitologia , Ceratopogonidae/parasitologia , Culicidae/parasitologia , República Tcheca , Ecossistema , Comportamento Alimentar , Feminino , Insetos Vetores/parasitologia , Insetos Vetores/fisiologia , Simuliidae/parasitologia , Trypanosoma/fisiologia , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia , Tripanossomíase/transmissão
11.
Folia Microbiol (Praha) ; 54(3): 246-56, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19649743

RESUMO

Anaplasma phagocytophilum has been first isolated from the blood of two Czech patients simultaneously with a cultivation of Borrelia burgdorferi sensu lato from their erythema migrans lesions. Cultivation of different Borrelia spp. from 12 erythema migrans biopsies, from 2 blood, one liquor and one placenta sample in BSK-H medium was successful. Adapted conventional methods targeting 16S rRNA and OspA genes for real-time polymerase chain reaction (PCR) and partial sequencing of these genes together with microscopical examinations of the blood smears provided a direct detection of the B. afzelii, B. burgdorferi, B. garinii, B. valaisiana and B. bissettii in the skin, B. garinii in the blood, placenta and liquor in 24 (36.3 %) patients, and A. phagocytophilum in 10 (15 %) patients with erythema migrans. Positive indirect IgM immunofluorescence against Anaplasma sp. was obtained in 7 cases, specific IgG antibodies were detected in 12 patients. Three women suffering from erythema migrans in the first trimester had positive PCR for Anaplasma and/or for Borrelia in the blood and two of them, later, in the placenta. Interpretation of laboratory data can bring important contribution to establishing the role of Anaplasma sp. in erythema migrans and forming the principle of precaution with laboratory diagnosis during pregnancy which always should be reflected in the resistance of Anaplasma sp. toward penicillins.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Borrelia burgdorferi/isolamento & purificação , Eritema Migrans Crônico/microbiologia , Complicações Infecciosas na Gravidez/microbiologia , Adolescente , Adulto , Idoso , Anaplasma phagocytophilum/imunologia , Anticorpos Antibacterianos/sangue , Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/genética , Borrelia burgdorferi/genética , Borrelia burgdorferi/imunologia , Diagnóstico Diferencial , Ehrlichiose/sangue , Ehrlichiose/diagnóstico , Ehrlichiose/microbiologia , Eritema Migrans Crônico/sangue , Eritema Migrans Crônico/diagnóstico , Feminino , Células HL-60 , Humanos , Lipoproteínas/genética , Doença de Lyme/sangue , Doença de Lyme/diagnóstico , Doença de Lyme/microbiologia , Masculino , Pessoa de Meia-Idade , Placenta/microbiologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico
12.
Med Vet Entomol ; 23(3): 277-80, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19531067

RESUMO

Feeding behaviour, host preferences and the spectrum of available hosts determine the role of vectors in pathogen transmission. Feeding preferences of blood-feeding Diptera depend on, among others factors, the willingness of flies to attack their hosts either in the open (exophagy) or in enclosed places (endophagy). As far as ornithophilic blood-feeding Diptera are concerned, the biting midges (Diptera: Ceratopogonidae) and blackflies (Diptera: Simuliidae) are generally considered to be strictly exophagous. We determined which blood-sucking Diptera enter nest cavities and feed on birds by placing sticky foil traps inside artificial nest boxes. A total of 667 females of eight species of biting midges of the genus Culicoides (Latreille, 1809) were captured on traps during 2006-2007, with Culicoides truncorum (Edwards, 1939) being the dominant species. DNA blood analyses of blood-engorged females proved that midges actually fed on birds nesting in the boxes. Three species were identified as endophagous: Culicoides truncorum, Culicoides pictipennis (Staeger, 1839), and Culicoides minutissimus (Zetterstedt, 1855). Our study represents the first evidence that ornithophilic biting midges are endophagous. The fact that we caught no blackflies in the bird boxes supports the exophagy of blackflies. We believe that our findings are important for surveillance programmes focusing on Diptera that transmit various bird pathogens.


Assuntos
Aves/parasitologia , Ceratopogonidae/fisiologia , Mordeduras e Picadas de Insetos , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Bluetongue/epidemiologia , Ceratopogonidae/patogenicidade , Feminino , Comportamento de Nidação
13.
Folia Microbiol (Praha) ; 52(4): 315-24, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18062179

RESUMO

The genotype of Borrelia burgdorferi sensu lato was detected in 371 out of 1244 ticks. Borrelia determination was based on partial sequencing of the 16S rRNA gene and real-time polymerase chain reactions for identification and quantitation of ospA and recA genes. Different Borrelia spp. were identified; B. garinii in 40% ticks followed by B. afzelii (36.3%), B. burgdorferi sensu stricto (12.9%), B. valaisiana (3.5%), B. lusitaniae (0.8%), B. bissettii (0.5%) and B. miyamotoi-like (0.5%). Cultivation of 30 borrelia strains in BSK-H medium, among them B. valaisiana, B. bissettii-like and B. miyamotoi-like strains was unique in Czechia. Calibrated microfluidic-based quantification showed differences in the concentration of the nucleic acids and molar mass of the outer surface proteins of different Borrelia spp. with standard sensitivity and specificity and was helpful for their identification. The outer surface protein OspA was absent in B. miyamotoi-like and the OspB protein in B. valaisiana, B. lusitaniae and in three subtypes of B. garinii.


Assuntos
Grupo Borrelia Burgdorferi/genética , Ixodes/microbiologia , Animais , Antígenos de Superfície/química , Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/química , Vacinas Bacterianas/genética , Sequência de Bases , Grupo Borrelia Burgdorferi/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/genética , Feminino , Variação Genética , Lipoproteínas/química , Lipoproteínas/genética , Masculino , Técnicas Analíticas Microfluídicas , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Recombinases Rec A/química , Recombinases Rec A/genética , Alinhamento de Sequência
14.
J Vector Ecol ; 31(2): 229-38, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17249339

RESUMO

Phlebotomus sergenti populations from different areas of the Mediterranean basin are known to exhibit high intraspecific variability. Previous studies of ITS2 revealed the presence of two branches that may represent sibling species. To corroborate this finding by other tools, two colonies of P. sergenti originating from Turkey and Israel, each belonging to a different ITS2 branch, were compared by three different methods: geometric morphometric analysis of wing shape, RAPD (random amplified polymorphic DNA), and cross-mating study. For geometric morphometric analysis, two-dimensional Cartesian coordinates of 16 landmarks from the wings were digitized and analyzed. Significant shape differences were found between colonies but not between sexes within each colony. RAPD results formed two distinctive clades corresponding to the origin of the colony but also showed heterogenity among members of both colonies. In cross-mating studies, viable hybrid F1 and F2 progeny were obtained when both Turkish males/Israeli females and Israeli males/Turkish females were crossed. F1 progeny was included in RAPD analysis and these hybrids formed a distinctive clade with an intermediate position between the two parental clades. No significant differences were found in egg production of crossed sand flies. The cross-mating study showed that there is no reproductive barrier between P. sergenti from different geographical areas. On the other hand, RAPD and geometric morphometric analysis revealed a significant difference between colonies and confirmed the suitability of previous ITS2 analysis for discrimination among sand fly populations. Further development of molecular markers should resolve a possible existence of sibling species within Phlebotomus sergenti.


Assuntos
Especiação Genética , Hibridização Genética , Phlebotomus/genética , Animais , Feminino , Variação Genética , Masculino , Phlebotomus/anatomia & histologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
15.
Int J Parasitol ; 34(11): 1221-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15491584

RESUMO

The regurgitation of metacyclic stages from the sand fly cardia is thought to be the prevailing mechanism of Leishmania transmission. This regurgitation may result through damage of the stomodeal valve and its mechanical block by the parasites. We found this phenomenon in three sand fly-Leishmania models and also in avian trypanosomes transmitted by Culex mosquitoes. Phlebotomus duboscqi, Phlebotomus papatasi, Lutzomyia longipalpis, and Culex pipiens were membrane-fed on blood containing Leishmania major, Leishmania chagasi (syn. infantum) and an unidentified avian Trypanosoma from Trypanosoma corvi clade, respectively. Females with the late-stage infections were processed for the optical and transmission electron microscopy. Localization of the parasites and changes to the stomodeal valve were in some aspects similar in all vector-parasite pairs studied: (i) a large plug of flagellates was observed in cardia region, (ii) parasites were attached to the chitin lining of the stomodeal valve by the formation of zonal hemidesmosome-like plaques. Leishmania promastigotes were found both attached to the valve as well as unattached in the lumen of midgut. The stomodeal valve of infected sand flies was opened, its chitin lining was destroyed and the unique filamentous structures on the apical end of cylindrical cells were degraded. In the Culex-Trypanosoma model, the whole population of epimastigotes was found in close contact with the chitin lining, and degenerative changes of the valve were less pronounced. We suggest that the phenomenon involving a blocked valve facilitating the regurgitation of parasites into the vertebrate host may occur generally in heteroxenous trypanosomatids transmitted by the bite of nematoceran Diptera.


Assuntos
Culex/parasitologia , Insetos Vetores/parasitologia , Leishmaniose/transmissão , Psychodidae/parasitologia , Tripanossomíase/transmissão , Animais , Quitina/metabolismo , Culex/ultraestrutura , Feminino , Insetos Vetores/ultraestrutura , Leishmaniose Cutânea/transmissão , Microscopia Eletrônica , Phlebotomus/parasitologia , Phlebotomus/ultraestrutura , Psychodidae/ultraestrutura
16.
Parasitol Res ; 92(2): 147-51, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14652745

RESUMO

Trypanosomes identified as Trypanosoma avium were found in the ornithophilic black flies ( Eusimulium latipes) attacking buzzard nestlings ( Buteo buteo). Parasites formed plugs and rosettes in the hindgut of the vector and were attached on the cuticular lining of the black fly anterior intestine (ileum) by hemidesmosome-like plaques. Hindgut stages from infected black flies were experimentally transmitted into canaries ( Serinus canaria) by ingestion of vectors and by contamination of host conjunctiva. This is the first clear evidence of such transmission in avian trypanosomes. Parasites survived in peripheral blood of birds at the least 10 months. In contrast to the direct inoculation of insect stages, parasites from culture failed to produce infection in experimental birds; this has consequences for laboratory studies of host susceptibility and transmission.


Assuntos
Doenças das Aves/transmissão , Canários/parasitologia , Insetos Vetores/parasitologia , Simuliidae/parasitologia , Tripanossomíase/veterinária , Animais , Doenças das Aves/parasitologia , Trypanosoma/isolamento & purificação , Tripanossomíase/transmissão
17.
Epidemiol Mikrobiol Imunol ; 53(4): 183-91, 2004 Nov.
Artigo em Tcheco | MEDLINE | ID: mdl-15633539

RESUMO

The spread of borreliosis depends on geographical, environmental and climatic factors as well as on the pathogenesis of the causative agent of the group of Borrelia burgdorferi sensu lato. The rise in the incidence of the disease and emergence of new symptoms are of concern. Relationships between genospecies and symptoms, their geographical spread and possible interference of other pathogens are the subject of the present study. Eighty-seven patients with borreliosis from Central and Eastern Bohemia and Moravia were enrolled in the study. Forty-nine patients of group 1 showed clinical positivity, 21 patients of group 2 tested positive at PCR screening and 17 patients of group 3 were culture positive. Forty-eight patients and 17 isolated strains showed positivity for plasmids and the Borrelia burgdorferi sensu lato genome in conventional nested PCR. Borrelial genotypes and subtypes were detected by direct sequencing of OspA and OspC products. Quantitative data were determined from specific product melting temperature curves for real time PCR. Based on sequencing of the OspA gene, B. garinii (subtypes 6, 5, 4 and 3), B. burgdorferi s.s. and B. afzelii were detected in 14 (51.8%), 8 (29.6%) and 5 (18.5%) out of 27 Central Bohemian patients, respectively. Eastern Bohemian patients showed predominance of B. garinii subtype 5 and co-infection with Anaplasmaphagocytophilum in 7.6%. The predominant causative agent in 25 Moravian patients was B. afzelii (11 patients, i.e. 44%), followed by B. burgdorferi s.s. (9 patients, 36%) and B. garinii 5 patients, i.e. 20%). Sequences of two hypervariable regions of the OspA and OspC genes and distances in phylogenetic trees showed differences not only between genospecies and subtypes but also between wild strains detected by direct sequencing from patient specimens and in vitro cultured strains. The greatest differences were found for patients with long-term borrelial infection.


Assuntos
Grupo Borrelia Burgdorferi/genética , Doença de Lyme/microbiologia , Antígenos de Bactérias/genética , Antígenos de Superfície/genética , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas , Grupo Borrelia Burgdorferi/classificação , República Tcheca/epidemiologia , Humanos , Incidência , Lipoproteínas/genética , Doença de Lyme/epidemiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
18.
New Microbiol ; 25(4): 437-48, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12437223

RESUMO

We report moderately severe cases of human ehrlichiosis and a lethal one caused by human granulocytic Ehrlichia, the HGE agent, closely related to Ehrlichia phagocytophila and Ehrlichia equi. Their vector is the Ixodes ricinus tick, which also transmits Borrelia burgorferi sensu lato in central, west and east regions of the Czech Republic. The diagnosis was established by PCR with sequence analysis of the genes encoding 16S rRNA of Ehrlichia and with reverse hybridization by using enzyme linked immunosorbent assay with different covalently coupled probes to the activated plate. Ten out of 47 patients and 10 huntsmen were PCR positive and 7 of them seroconverted to the HGE. Coinfection of Ehrlichia phagocytophila with Borrelia burgdorferi sensu lato was detected in 3 patients. Ehrlichia spp., the HGE agent, was isolated and propagated only from one patient in the HL-60 promyelocytic cell line. The maintenance of Ehrlichia in culture and in patients was assayed also by immunocytological staining and electron microscopy. Sequence or hybridization analysis of PCR results in different wild mammals and birds showed significant sources of Ehrlichia fagocytophila in nature. Three variants of E. phagocytophila in wild roe deer and boars, as well as for the first time in birds, have been described. Cultures from the blood of horses, and from the spleen and kidney specimens of roes and boars, PCR positive for Ehrlichia spp., displayed a disappearing level of the pathogen or contamination with other bacteria.


Assuntos
Bartonella/isolamento & purificação , Grupo Borrelia Burgdorferi/isolamento & purificação , Ehrlichia/isolamento & purificação , Ixodes/microbiologia , Animais , Bartonella/classificação , Bartonella/genética , Grupo Borrelia Burgdorferi/classificação , Grupo Borrelia Burgdorferi/genética , República Tcheca , Ehrlichia/classificação , Ehrlichia/genética , Ehrlichiose/microbiologia , Ensaio de Imunoadsorção Enzimática , Humanos , Ixodes/genética , Microscopia Eletrônica , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Parasitology ; 125(Pt 3): 253-63, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12358422

RESUMO

Avian trypanosomes are widespread parasites of birds, the transmission of which remains mostly unclear, with various blood-sucking insects mentioned as possible vectors. A search for vectors of trypanosomes of sparrowhawk (Accipiter nisus), buzzard (Buteo buteo), lesser-spotted eagle (Aquila pomarina) and kestrel (Falco tinnunculus) was performed in Czech and Slovak Republics. Black flies (Eusimulium spp.), hippoboscid flies (Ornithomyia avicularia), mosquitoes (Culex pipiens pipiens) and biting midges (Culicoides spp.), trapped while attempting to feed on raptor nestlings, were found to contain trypanosomatids in their intestine. Trypanosomes from the raptors and blood-sucking insects were isolated, and their 18S rRNA sequences were used for species identification and for the inference of intra- and interspecific relationships. Together with the trypanosome isolated from a black fly, the bird trypanosomes formed a well-supported Trypanosoma avium clade. The isolates derived from hippoboscid flies and mosquitoes are most likely also avian trypanosomes infecting birds other than the studied raptors. Analysis of the kinetoplast, that has features characteristic for the avian trypanosomes (minicircle size; dimensions of the kinetoplast disc), provided further evidence for the identification of vectors. It is suggested that all trypanosomes isolated from raptors included in this study belong to the T. avium complex and are transmitted by the ornithophilic simuliids such as Eusimulium securiforme.


Assuntos
Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Insetos Vetores/parasitologia , Aves Predatórias/parasitologia , Trypanosoma/isolamento & purificação , Animais , Animais Selvagens , Sequência de Bases , DNA de Cinetoplasto/genética , Insetos/parasitologia , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Trypanosoma/classificação , Trypanosoma/genética , Trypanosoma/ultraestrutura
20.
Vet J ; 163(2): 147-54, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12093189

RESUMO

Hammondia heydorni is thought to be a non-pathogenic coccidian parasite of dogs that is closely related to Neospora caninum, an important parasite of cattle and dogs. Oocysts of these two species are morphologically indistinguishable from each other. A population of 2240 dogs in the Czech Republic was screened for the presence of H. heydorni/N. caninum oocysts and five (0.22%), represented by five of 3135 faecal samples (0.16%), were positive. The internal transcribed spacer 1 region of the rRNA gene (ITS1) from two isolates were cloned and the DNA sequences were identical with those of the ITS1 of H. heydorni. Based on the rRNA sequences available for H. heydorni and related coccidia, the primer pair JS4-JS5 was designed to amplify the 3' end of the small subunit (SSU) rRNA gene and ITS1 of H. heydorni. When tested on DNA extracted from a variety of parasites, the primers amplified a specific 267 bp fragment in our isolates only. The presence of DNA equivalent to 10 oocysts was sufficient for the amplification of the ITS1. We present a PCR-based diagnostic method as the only fast and reliable method for the diagnosis of H. heydorni in dogs.


Assuntos
Coccidiose/veterinária , DNA Espaçador Ribossômico/genética , Doenças do Cão/parasitologia , Fezes/parasitologia , Genes de RNAr/genética , Neospora/genética , Neospora/isolamento & purificação , Animais , Sequência de Bases , Clonagem Molecular , Coccidiose/diagnóstico , Coccidiose/parasitologia , DNA de Protozoário/análise , Diagnóstico Diferencial , Doenças do Cão/diagnóstico , Cães , Dados de Sequência Molecular , Neospora/classificação , Reação em Cadeia da Polimerase , RNA de Protozoário/análise , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Zigoto/química , Zigoto/citologia
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