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1.
To determine additional reservoirs for Bartonella rochalimae, we examined samples from several wildlife species. We isolated B. rochalimae from 1 red fox near Paris, France, and from 11 raccoons and 2 coyotes from California, USA. Co-infection with B. vinsonii subsp. berkhoffii was documented in 1 of the coyotes.  相似文献   

2.
Bartonella spp. infect humans and many animal species. Mainly because PCR studies have demonstrated Bartonella DNA in ticks, some healthcare providers believe that these microorganisms are transmitted by ticks. B. henselae, in particular, is regarded as being present in and transmissible by the Ixodes scapularis tick. The presence of a microbial agent within a tick, however, does not imply that the tick might transmit it during the course of blood feeding and does not confer epidemiologic importance. After a critical review of the evidence for and against tick transmission, we conclude that transmission of any Bartonella spp. by ticks, to animals or humans, has not been established. We are unaware of any well-documented case of B. henselae transmission by I. scapularis ticks.  相似文献   

3.
We report the case of a 55 year-old man presenting with a double aortic and mitral endocarditis for which resected valve culture was repeatedly negative. Specific PCR made on valves because of highly positive blood tests for Bartonella henselae remained negative. A molecular approach was made with 16S rDNA PCR, followed by sequencing. Bartonella quintana was identified as the etiology of endocarditis. B. quintana, “fastidious” bacteria, even if hard to identify in a laboratory, is often reported as a blood culture negative endocarditis (BCNE) agent. Molecular biology methods have strongly improved the diagnosis of BCNE. We propose a review of the literature focusing on the interest of broad-spectrum PCR on valve for the etiological diagnosis of BCNE.  相似文献   

4.
To evaluate the risk for emerging human infections caused by zoonotic Bartonella spp. from exotic small mammals, we investigated the prevalence of Bartonella spp. in 546 small mammals (28 species) that had been imported into Japan as pets from Asia, North America, Europe, and the Middle and Near East. We obtained 407 Bartonella isolates and characterized them by molecular phylogenetic analysis of the citrate synthase gene, gltA. The animals examined carried 4 zoonotic Bartonella spp. that cause human endocarditis and neuroretinitis and 6 novel Bartonella spp. at a high prevalence (26.0%, 142/546). We conclude that exotic small mammals potentially serve as reservoirs of several zoonotic Bartonella spp.  相似文献   

5.
Since 1966 the triatomines were grouped in complexes and specific subcomplexes. Although the complex and subcomplexes not have taxonomic importance, should be monophyletic groups and cytogenetic tools have proved to be of great importance to characterize these species groupings. Based on this, this paper aims to describe the chromosomal characteristics and heterochromatic pattern of Matogrossensis and Rubrovaria subcomplexes, in order to contribute to the taxonomic and evolutionary relationships of these vectors. In this study, at least three males from each species (Triatoma baratai, Triatoma costalimai, Triatoma guazu, Triatoma jurbergi, Triatoma matogrossensis, Triatoma vandae, Triatoma williami, Triatoma carcavalloi, Triatoma circummaculata, Triatoma klugi, Triatoma pintodiasi and Triatoma rubrovaria) were analyzed by means analyzed by means of cytogenetic techniques of C-banding. All species showed the same cytogenetic characteristics: 22 chromosomes, low variation in the size of autosomes, sex chromosome Y larger than X, initial prophase composed of only one heterochromatic chromocenter formed by the sex chromosomes X and Y (except for T. pintodiasi that presented the sex chromosomes individualized during all stages of prophase) and presence of constitutive heterochromatin restricted to sex chromosome Y. These characteristics, although common to Matogrossensis and Rubrovaria subcomplexes allow to distinguish these species of species grouped in most of South America subcomplexes, as Brasiliensis, Maculata, Sordida and Insfestans. Thus, the cytogenetic analysis was of extreme importance to differentiate both subcomplexes of the other subcomplexes of South America. However, probably due to evolutionary proximity existing between these subcomplexes was not possible to observar species differences that make up the Matogrossensis subcomplex of the Rubrovaria subcomplex. Therefore, we emphasize that new comparative analyzes, as experimental hybrid crosses and molecular cytogenetic analysis are necessary to clarify the evolutionary relationship between these important subcomplexes of vectors.  相似文献   

6.
The term “complex” emerged in the literature at the beginning of the genomic era associated to taxonomy and grouping organisms that belong to different species but exhibited similar patterns according to their morphological, physiological and/or other phenotypic features. DNA–DNA hybridization values ⩾70% and high identity on 16S rRNA gene sequences were recommended for species delineation. Electrophoretic methods showed in some cases to be useful for species identification and population structure but the reproducibility was questionable. Later, the implementation of polyphasic approaches involving phenotypic and molecular methods brought new insights into the analysis of population structure and phylogeny of several “species complexes”, allowing the identification of new closely related species. Likewise, the introduction of multilocus sequence typing and sequencing analysis of several genes offered an evolutionary perspective to the term “species complex”. Several centres worldwide have recently released increasing genetic information on distinct microbial species. A brief review will be presented to highlight the definition of “species complex” for selected microorganisms, mainly the prokaryotic Acinetobacter calcoaceticusAcinetobacter baumannii, Borrelia burgdorferi sensu lato, Burkholderia cepacia, Mycobacterium tuberculosis and Nocardia asteroides complexes, and the eukaryotic Aspergillus fumigatus, Leishmania donovani and Saccharomyces sensu stricto complexes. The members of these complexes may show distinct epidemiology, pathogenicity and susceptibility, turning critical their correct identification. Dynamics of prokaryotic and eukaryotic genomes can be very distinct and the term “species complex” should be carefully extended.  相似文献   

7.
ObjectivesA multiplex real-time polymerase chain reaction (RT-PCR) method was developed for the identification of three Vibrio species: Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus.MethodsSpecific primers and probes targeting the hlyA, tlh, and vvhA genes were selected and used for multiplex real-time PCR to confirm the identification of V. cholerae, V. parahaemolyticus, and V. vulnificus, respectively. This method was applied to screen Vibrio species from environmental samples and combining it with a culture-based method, its effectiveness was evaluated in comparison with culture-based methods alone.ResultsSpecific PCR fragments were obtained from isolates belonging to the target species, indicating a high specificity of this multiplex real-time PCR. No cross-reactivity with the assay was observed between the tested bacteria. The sensitivity of the multiplex real-time PCR was found to have a lower limit of 104 colony-forming units/reaction for all three Vibrio species. The combination strategy raised the isolation ratio of all three Vibrio species 1.26- to 2.75-fold.ConclusionThis assay provides a rapid, sensitive, and specific technique to detect these three Vibrio species in the environment.  相似文献   

8.
In the present work, we carried out a morphological, biometrical and molecular study of whipworms Trichuris Roederer, 1761 (Nematoda: Trichuridae) parasitizing Papio ursinus Keer 1792 (Chacma baboon). Biometrical and molecular data suggest a new species of Trichuris parasitizing baboons. In addition of main morphological features (spicule, spicule sheath, spicule tube, proximal cloacal tube, distal cloacal tube, vulva, vagina), the mean values of individual variables between Trichuris colobae, Trichuris suis, Trichuris trichiura examined by Student's t tests suggest that T. ursinus n. sp. constitutes a new species. The combined analysis of three markers (cox1, cob and ITS2) revealed a sister relationships between T. colobae and T. ursinus n. sp. Mitochondrial sequences revealed a higher inter-specific similarity between T. ursinus n. sp., T. suis and T. colobae. Phylogenetic hypotheses for both mitochondrial genes strongly supported distinct genetic lineages corresponding to different species of the genus Trichuris associated with certain hosts. Thus, T. suis, T. colobae and T. ursinus n. sp. appeared as a sister group and separated from Trichuris spp. from humans and other species of primates.  相似文献   

9.
The subgenus Transphlebotomus comprises sand fly species with distribution markedly restricted to the Mediterranean basin and suspected of Leishmania transmission. Only three species, Phlebotomus mascittii, Phlebotomus canaaniticus and Phlebotomus economidesi, have been described up to the present. Due to their similar morphology, proper identification remains difficult and relies mainly on molecular markers. We studied sand fly species of this subgenus from Crete and south-western coast of Anatolia. Based on the sequencing analysis of mitochondrial genes (cytochrome b, NADH dehydrogenase subunit 4, cytochrome oxidase I), two new Transphlebotomus species were identified and subsequently distinguished also by morphological characters: Phlebotomus anatolicus n. sp. and Phlebotomus killicki n. sp. Moreover, Ph. economidesi, previously only recorded from Cyprus, was found in Turkey sympatrically with these two new species. Based on the divergence time estimates, the first split has occurred in the subgenus Transphlebotomus ∼10 million years ago and the paleogeographic events took place around the Aegean and Mediterranean regions were suggested as the main drivers of the diversification of the subgenus. Our findings indicate that for Transphlebotomus species, morphological identification should be confirmed by molecular approaches, especially for investigations concerning their possible vectorial role in Leishmania transmission.  相似文献   

10.
The genus Anaplasma (family Anaplasmataceae, order Rickettsiales) includes obligate intracellular alphaproteobacteria that multiply within membrane-bound vacuoles and are transmitted by Ixodidae ticks to vertebrate hosts. Since the last reclassification of Anaplasmataceae twenty years ago, two new Anaplasma species have been identified. To date, the genus includes eight Anaplasma species (A. phagocytophilum, A. marginale, A. centrale, A. ovis, A. bovis, A. platys, A. odocoilei, and A. capra) and a large number of unclassified genovariants that cannot be assigned to known species. Members of the genus can cause infection in humans and a wide range of domestic animals with different degrees of severity. Long-term persistence which, in some cases, is manifested as cyclic bacteremia has been demonstrated for several Anaplasma species. Zoonotic potential has been shown for A. phagocytophilum, the agent of human granulocytic anaplasmosis, and for some other Anaplasma spp. that suggests a broader medical relevance of this genus. Genetic diversity of Anaplasma spp. has been intensively studied in recent years, and it has been shown that some Anaplasma spp. can be considered as a complex of genetically distinct lineages differing by geography, vectors, and host tropism. The aim of this review was to summarize the current knowledge concerning the natural history, pathogenic properties, and genetic diversity of Anaplasma spp. and some unclassified genovariants with particular attention to their genetic characteristics. The high genetic variability of Anaplasma spp. prompted us to conduct a detailed phylogenetic analysis for different Anaplasma species and unclassified genovariants, which were included in this review. The genotyping of unclassified genovariants has led to the identification of at least four distinct clades that might be considered in future as new candidate species.  相似文献   

11.
We describe a PCR-RFLP-based method that allows reliable identification of four species of nematode parasites presenting similar infective third-stage larvae (L3) with a flagelliform tail and more than 16 intestinal cells, commonly observed in gastrointestinal tract of ruminants in France. Molecular analysis of the second internal transcribed spacer (ITS2) of ribosomal DNA, considered as a specific marker for Strongylida, revealed four robust monophyletic clades corresponding to species Chabertia ovina, Oesophagostomum sikae, Oesophagostomum radiatum and Oesophagostomum venulosum. One restriction enzyme (DdeI) was used to digest this domain, and we observed four different and clear digestion patterns according to these species (adults or larvae). Hence, this new method is a good tool easy to use for veterinary laboratories to characterize the different species, and allows considering possible cross transmission between domestic and wild ruminants, especially cervids often incriminated as potential reservoir of parasites for cattle. Moreover, thanks to this new tool, necroscopic analyses could be substituted by coprological methods, a non-invasive approach.  相似文献   

12.
Beilong virus (BeiV), a member of the newly recognized genus Jeilongvirus of family Paramyxoviridae, has been reported with limited geographic and host scopes, only in Hongkong, China and from two rat species. Here, by next-generation sequencing (NGS) on dominant wild small animal species in 4 provinces in China, we obtained a complete sequence of BeiV strain from Rattus norvegicus in Guangdong, neighboring HongKong, China. We then made an expanded epidemiological investigation in 11 provinces to obtain the geographic distribution and genetic features of this virus. Altogether 7168 samples from 2005 animals (1903 rodents, 100 shrews, 2 mustelidaes) that belonged to 33 species of Cricetidae, Muridae, Sciuridae and Dipodidae family of Rodentia, 3 species of Soricidae family of Soricomorpha, 2 species of Mustelidae family of Carnivora were examined by RT-PCR and sequencing. A positive rate of 3.7% (266/7168) was obtained that was detected from 22 animal species, including 5 species of Cricetidae family, 12 species of Muridae family, 2 species of Sciuridae family and 3 species of Soricidae family. Phylogenetic analyses based on 154 partial Large gene sequences grouped the current BeiV into two lineages, that were related to their geographic regions and animal hosts. Our study showed the wide distribution of BeiV in common species of wild rodents and shrews in China, highlighting the necessity of epidemiological study in wider regions.  相似文献   

13.
This is the first study to explore the potential of various geometric morphometrics methods to help the morphological diagnostic of tsetse species, vectors of human and animal trypanosomiases in sub-Saharan Africa. We compared landmarks, semilandmarks and outlines techniques on male and female samples of species, and suggested adapted strategies according to the countries and their own Glossina fauna. We could compare up to 7 taxa belonging to the three main subgenera of the Glossina genus: Nemorhina (5 species), Glossina (1 species) and Austenina (1 species). Our sample included the major vectors of sleeping sickness: G. palpalis palpalis, G. p. gambiensis, G. fuscipes fuscipes and G. f. quanzensis, as well as two important vectors of African animal trypanosomoses: G. tachinoides and Glossina morsitans submorsitans. The average level of correct species recognition by the wing shape was satisfactory, and slightly higher for females than for males. The best scores of correct assignment, in both sexes, were obtained by the contour technique (96% of correct attribution in females, 92% in males), slightly higher than for semilandmarks (95% and 91%) or landmarks (94% and 89%) techniques. We made our images of wings freely available to be used as reference images (http://mome-clic.com), and we describe the conditions and the analytical steps to be followed to identify unknown specimens using external reference images. Under adequate conditions, such use of reference images obtained from a free access server could help species identification of new samples anywhere in Africa.  相似文献   

14.

Background

Knowledge about the amphistomid fauna in Iranian domestic ruminants depends on the studies conducted almost 30 years ago. The last situation in cattle is introduced here in the provinces in south coast of Caspian Sea.

Methods

Amphistomid species were collected from cattle at slaughter houses of the provinces Gilan and Mazanderan in 2010. Median sagittal sections were prepared by the conventional method. Species were identified by the histomorphological pecularities of the muscular argans.

Results

Five amphistomid species, Paramphistomum cevri, P. gotoi, Calicophoron calicophorum, Carmyerius spatiosus and Gastrothylax compressus, recovered. Calicophoron calicophorum is a new species for Iran. Criteria used in identification of the species were illustrated.

Conclusion

Iran has a rich amphistomid fauna and mostly under the influence of oriental conditions.  相似文献   

15.
《Ticks and Tick》2020,11(6):101534
Ticks of the family Ixodidae are vectors of important pathogens in human and animal health. Birds are involved in long-distance transport and dispersion of hard ticks. Tick infestations on wild birds mostly involve species within the genera Amblyomma, Ixodes, and Haemaphysalis. In Colombia, tick research is scarce and there are no studies to date about the associations between wild birds and ticks. We aimed to contribute to the knowledge of the associations between wild birds and hard ticks based on the collection of 2314 wild birds belonging to 29 families in Caldas – Colombia between 2015 and 2019. In total, we collected 133 hard ticks that were found parasitizing 78 birds representing 45 species and 14 wild bird families. We report at least seven tick species on birds confirmed by morphological and molecular methods: Amblyomma longirostre, Amblyomma varium, Amblyomma dissimile, Amblyomma ovale, Amblyomma nodosum, Amblyomma calcaratum and Haemaphysalis leporispalustris. In addition, we recorded three Ixodes species, which yielded DNA sequences that did not have high identity (≤ 95 %) to any species in GenBank. Ticks were found infesting resident and migratory boreal birds. This is the first study addressing the associations between wild birds and hard ticks in Colombia. We describe new associations between birds and ticks in the Americas.  相似文献   

16.

Background

Genus Acanthocolpus (Trematoda: Acanthocolpiidae) is one of the most important zoonotic digenean with wide geographic distribution in the world. The purpose of the present study was to describe morphological and morphometrical characteristics of Acanthocolpus species, currently prevalent in marine fish fauna of Puri coast, Orissa, India.

Methods

Gastro-intestinal organs of Leiognathus daura (Cuvier) in Puri coast, Orissa, India, were examined for infectivity with digenean trematode species. For examination and measurements of helminthes, acetoalum carmine staining was performed, followed by camera Lucida drawings of morphological characters and measurements of morphometrical criteria with a calibrated microscope. Using valid trematode systematic keys, almost all the parasites were identified at the level of species.

Results

Overall, 36 marine fishes were found infected with at least one species of Acanthocolpus. Considering morphological characteristics of Acanthocolpus, two species were identified as new species including Acanthocolpus durghai sp.nov. and Acanthocolpus amrawatai sp.nov.

Conclusion

During the survey of helminth parasites, collected six different species of the genus Acanthocolpus, out of these two are new species, another is redescribed to show certain variation, the new parasite was obtain from the intestine of marine fish Leiognathus daura (Cuvier)  相似文献   

17.
We detected Bartonella quintana in 48.6% of captive rhesus macaques from an animal facility in Beijing, China. Prevalence of infection increased over the period of observation. Our findings suggest that macaques may serve as reservoir hosts for B. quintana and that Pedicinus obtusus lice might act as efficient vectors.  相似文献   

18.
《Ticks and Tick》2020,11(5):101456
In Slovakia, little knowledge is available on the occurrence, hosts and vectors of Borrelia miyamotoi of the relapsing fever group. In the current study, 2160 questing and rodent-attached ticks of six species (Ixodes ricinus, Ixodes trianguliceps, Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna and Haemaphysalis inermis), 279 fleas belonging to 9 species (Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus assimilis, Megabothris turbidus, Amalareus penicilliger, Hystrichopsylla orientalis, Ctenophthalmus uncinatus, Doratopsylla dasycnema and Nosopsyllus fasciatus) and skin biopsies from 245 small mammals belonging to eight species (Apodemus agrarius, Apodemus flavicollis, Apodemus uralensis, Myodes glareolus, Crocidura leucodon, Micromys minutus, Microtus arvalis, Microtus subterraneus) were screened for the presence of B. miyamotoi DNA. The overall prevalence of B. miyamotoi found in questing and rodent-attached ticks was 1.8% (23 positive/1260 examined) and 3.4% (31 positive/900 examined), respectively. Borrelia miyamotoi was detected in questing I. ricinus, rodent-attached I. ricinus and H. inermis ticks, and in one male of the common vole (M. arvalis) in different habitats (mainly rural) in eastern Slovakia. However, B. miyamotoi was not found in any of the tested fleas. Our findings indicate that rural habitats with different species of tick vectors and hosts are appropriate for the occurrence of B. miyamotoi.  相似文献   

19.
As a result of the research carried out in Lakes Duszatyńskie and the Olchowaty stream, a new European site with Geissleria declivis (Hust.) Lange-Bert. was found — a new species for Poland. The highest abundance of G. declivis has been observed on sandy substrate and small stones in the littoral zone of the Upper Lake during the spring season. The species occurred together with Achnanthidium minutissimum (Kütz.) Czarn. var. minutissimum, A. catenatum (Bily & Marvan), Fragilaria leptostauron (Ehrenb.) Hust. var. leptostauron and F. pinnata Ehrenb. var. pinnata. Our observations revealed that G. declivis develops in lentic water bodies with medium organic matter content and neutral pH. The species seems to prefer mesotrophic waters with low to medium electrolyte content and oligosaprobous. The species morphology and identity is documented in a series of light microscopic (LM) images and for the first time under a scanning electron microscope (SEM).  相似文献   

20.
Toxicity of cadmium, copper and zinc was tested on four green algal species (Ankistrodesmus fusiformis, Chlorella ellipsoidea, Monoraphidium contortum and Scenedesmus acuminatus) isolated from a highly polluted river (Matanza–Riachuelo River, Buenos Aires, Argentina). The relative abundance of these species in river waters showed that C. ellipsoidea was the most abundant species (mean 4,540 ind mL?1), whereas the less abundant species was S. acuminatus (mean 220 ind mL?1). The most sensitive species was A. fusiformis, which EC50 were Cd = 141 μg L?1, Cu = 72 μg L?1, and Zn = 199 μg L?1, whereas C. ellipsoidea was the most resistant species to copper (EC50 = 489 μg L?1) and cadmium (EC50 = 429 μg L?1), and M. contortum and S. acuminatus were the most resistant species to zinc (EC50 = 381 and 394 μg L?1, respectively).  相似文献   

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