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1.
J Vet Diagn Invest ; 32(4): 611-615, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32687008

RESUMO

The only Sarcocystis species currently known to inhabit the fibers of skeletal and cardiac muscles in horses are S. fayeri, S. bertrami, and S. asinus. We describe herein the invasion of myofibers in a horse by S. gigantea, a sheep-specific species with low virulence in the original host. A hunter gelding was referred to a veterinary surgeon in Newmarket (UK). The anamnestic data reported that the horse had an initial history of swelling of the right forelimb with fluid on the front of the carpus and edema spreading up the forearm. Subsequently, 2 firm lumps were found on the left pectoral muscle adjacent to the axilla of the left forelimb. Histologic examination of biopsies from the lumps revealed multifocal granulomatous eosinophilic myositis associated with intact and degenerate encysted parasites, consistent with Sarcocystis spp. Based on amplification and DNA sequencing of the 18S rRNA gene obtained from formalin-fixed, paraffin-embedded tissue blocks, S. gigantea was identified. The presence of sarcocysts in equine skeletal muscles has been considered an incidental finding, and there are only sporadic associated reports of myositis. Our finding suggests that some Sarcocystis spp. have a wider intermediate host range than believed previously, and that Sarcocystis of other species (not considered horse-associated) can invade the muscle fibers of equids, leading to myositis.


Assuntos
Doenças dos Cavalos/patologia , Miosite/veterinária , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , Cavalos , Masculino , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/parasitologia , Distrofia Muscular do Cíngulo dos Membros/patologia , Miosite/diagnóstico , Miosite/parasitologia , Miosite/patologia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Sarcocistose/patologia , Análise de Sequência de DNA/veterinária
2.
Folia Parasitol (Praha) ; 672020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32350156

RESUMO

Here we describe the new trypanosomatid, Phytomonas borealis sp. n., from the midgut of the spiked shieldbugs, Picromerus bidens (Linnaeus), collected in two locations, Novgorod and Pskov Oblasts of Russia. The phylogenetic analyses, based on the 18S rRNA gene, demonstrated that this flagellate is a sister species to the secondary monoxenous Phytomonas nordicus Frolov et Malysheva, 1993, which was concurrently documented in the same host species in Pskov Oblast. Unlike P. nordicus, which can complete its development (including exit to haemolymph and penetration into salivary glands) in Picromerus bidens, the new species did not form any extraintestinal stages in the host. It also did not produce endomastigotes, indispensable for transmission in other Phytomonas spp. These observations, along with the fact that P. bidens overwinters at the egg stage, led us to the conclusion that the examined infections with P. borealis were non-specific. Strikingly, the flagellates from the Novgorod population contained prokaryotic endosymbionts, whereas the parasites from the second locality were endosymbiont-free. This is a first case documenting presence of intracellular symbiotic bacteria in Phytomonas spp. We suggest that this novel endosymbiotic association arose very recently and did not become obligate yet. Further investigation of P. borealis and its intracellular bacteria may shed light on the origin and early evolution of endosymbiosis in trypanosomatids.


Assuntos
Fenômenos Fisiológicos Bacterianos , Heterópteros/parasitologia , Simbiose , Trypanosomatina/classificação , Animais , Heterópteros/crescimento & desenvolvimento , Ninfa/crescimento & desenvolvimento , Ninfa/parasitologia , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Federação Russa , Trypanosomatina/microbiologia
3.
Folia Parasitol (Praha) ; 672020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32075950

RESUMO

Faecal samples from the rock hyrax (Procavia capensis jayakari Thomas) were collected from the Ibex Reserve in central Saudi Arabia. Eimerian oocysts, which are believed to represent a new species described here as Eimeria tamimi sp. n., were detected in 40 out of 93 samples. Oocysts were fully sporulated in 24-48 hours at 25 ± 2 °C. Sporulated oocysts of E. tamimi sp. n. were ovoid, measuring 35-42 × 19-25 µm (39 × 23 µm), a length/width ratio 1.5-2 (1.7). Oocyst wall was bilayered and measured 1.5 µm in thickness. Micropyle, oocyst residuum and polar granules were not present. Sporocysts are elongate, measuring 12-18 × 9-12 µm (15 × 10 µm), with a length/width ratio 1.1-1.8 (1.5) prominent Stieda bodies and sporocyst residuum. Experimental infection of two clinically healthy rock hyraxes with sporulated oocysts of E. tamimi sp. n. resulted in shedding unsporulated oocysts 5-10 days post infection. Partial sequences of 18S ribosomal RNA (18S rDNA) and cytochrome C oxidase subunit 1 (COI) regions were amplified using the polymerase chain reaction (PCR) and sequenced. Phylogenetic analysis based on 18S rDNA using maximum likelihood (ML) and Bayesian inference (BI) methods revealed that E. tamimi sp. n. grouped with Eimeria quokka Barker, O'Callaghan et Beveridge, 1988, E. mundayi Barker, O´Callaghan et Beveridge, 1988, E. potoroi Barker, O'Callaghan et Beveridge, 1988 and E. gaimardi Barker, O'Callaghan et Beveridge, 1988 marsupials. Eimerian species have been regarded as a paraphyletic group and the present investigation confirmed the conflict between phenotypic traits, used widely in the classification of this group of parasites.


Assuntos
Coccidiose/veterinária , Eimeria/fisiologia , Procaviídeos , Animais , Coccidiose/parasitologia , Eimeria/classificação , Eimeria/genética , Complexo IV da Cadeia de Transporte de Elétrons/análise , Oocistos/fisiologia , Filogenia , Proteínas de Protozoários/análise , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Arábia Saudita
4.
Parasitol Int ; 75: 102048, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31891767

RESUMO

Kudoa hexapunctata was taxonomically separated from Kudoa neothunni, but their main host is tuna. K. hexapunctata has been identified as causative agent of foodborne diseases associated with the ingestion of raw Pacific bluefin tuna (PBT) in Japan, but K. neothunni has not. Therefore, it is clinically and epidemiologically important to detect and distinguish these two species. In the present study, we developed a novel duplex polymerase chain reaction (dPCR) targeting the 28S rRNA gene sequences of K. hexapunctata and K. neothunni. The dPCR amplified the desired genetic regions of each species, and the detection limit was 10 copies/reaction. A total of 36 retail tuna samples from different fishing ports were purchased and tested by dPCR. Thirty-one tested positive for K. hexapunctata and four tested positive for K. neothunni. Several retail PBT samples were examined in some of the fishing ports, and among these samples, the detection rates of K. hexapunctata was higher than 85%, and the rates were similar between wild and farmed PBT. The detection rates of K. hexapunctata in wild and farmed retail PBT were 75% and 71%, respectively, in May. However, the rates in June and July were 100% for both. K. hexapunctata and K. neothunni myxospores were not observed in the dPCR-positive samples, except in juvenile PBT, suggesting that the number of parasites was insufficient to cause foodborne disease. Thus, dPCR is a useful method for detecting and distinguishing K. hexapunctata and K. neothunni, and can be used in epidemiological studies of these parasites.


Assuntos
Doenças dos Peixes/diagnóstico , Parasitologia de Alimentos/métodos , Myxozoa/isolamento & purificação , Doenças Parasitárias em Animais/diagnóstico , Reação em Cadeia da Polimerase/veterinária , Alimentos Marinhos/parasitologia , Atum , Animais , Doenças dos Peixes/parasitologia , Japão , Myxozoa/classificação , Doenças Parasitárias em Animais/parasitologia , Reação em Cadeia da Polimerase/métodos , RNA de Protozoário/análise , RNA Ribossômico 28S/análise , Especificidade da Espécie , Atum/parasitologia
5.
Transbound Emerg Dis ; 67(3): 1213-1221, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31845493

RESUMO

Theileria equi, one of the primary pathogens causing equine piroplasmosis, has previously been sub-classified into a number of clades on the basis of 18S SSU rRNA gene sequence diversity. This partitioning of the parasite population has potential implications for host immunity, treatment and vaccine development. To detect and identify different clade genotypes among and within individual equine blood samples, a novel PCR-based technique was designed and optimized. Theileria equi has only recently been described in The Gambia, and the developed genotyping technique was used to analyse blood samples taken from 42 piroplasmosis-positive horses and donkeys within the country. Three different T. equi genotypes were detected within the population, including the same genotype as the recently described Theileria haneyi, with 61.9% of individuals found to be infected with more than one genotype. Overall, there was a trend that males were more likely to have a multiple genotype infection. Thus, the novel genotyping technique has been shown to be effective in analysis of field populations and offers researchers a rapid method of identifying multiple T. equi genotypes both within individuals and equine populations in epidemiological studies.


Assuntos
Variação Genética , Doenças dos Cavalos/epidemiologia , Theileria/genética , Theileriose/epidemiologia , Animais , Gâmbia/epidemiologia , Técnicas de Genotipagem/veterinária , Doenças dos Cavalos/virologia , Cavalos , Prevalência , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Theileriose/virologia
6.
J Eukaryot Microbiol ; 67(1): 76-85, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419341

RESUMO

We report the morphology and morphogenesis of Urosoma caudata (Ehrenberg, 1833) Berger, 1999 based on in vivo observation and protargol impregnation and provide an improved diagnosis of U. caudata based on previous and current work. Urosoma caudata differs from its congeners mainly by the combination of the following features: tail-like posterior end, colorless cortical granules, and two macronuclear nodules. Urosoma caudata shares most of the ontogenetic features with its congeners: the oral primordium of the opisthe develops apokinetally, and the frontal-ventral-transverse cirral anlagen develop in five streaks. However, a unique morphogenetic characteristic is recognizable: the anlagen of three dorsal kineties occur de novo to the left of the parental structures differing from their intrakinetal origin in other Urosoma species. The first record of the 18S rRNA gene sequence for the species is also provided. Phylogenetic analyses based on 18S rRNA gene sequence data suggest that the genus Urosoma is a nonmonophyletic group.


Assuntos
Sporadotrichina/classificação , Sporadotrichina/citologia , Sequência de Aminoácidos , China , Morfogênese , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Alinhamento de Sequência , Sporadotrichina/crescimento & desenvolvimento
7.
Microb Ecol ; 79(3): 631-643, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31664477

RESUMO

Marine phytomyxids represent often overlooked obligate biotrophic parasites colonizing diatoms, brown algae, and seagrasses. An illustrative example of their enigmatic nature is the phytomyxid infecting the seagrass Halophila stipulacea (a well-known Lessepsian migrant from the Indo-Pacific to the Mediterranean Sea). In the Mediterranean, the occurrence of this phytomyxid was first described in 1995 in the Strait of Messina (southern Italy) and the second time in 2017 in the Aegean coast of Turkey. Here we investigated, using scuba diving, stereomicroscopy, light and scanning electron microscopy, and molecular methods, whether the symbiosis is still present in southern Italy, its distribution in this region and its relation to the previous reports. From the total of 16 localities investigated, the symbiosis has only been found at one site. A seasonal pattern was observed with exceptionally high abundance (> 40% of the leaf petioles colonized) in September 2017, absence of the symbiosis in May/June 2018, and then again high infection rates (~ 30%) in September 2018. In terms of anatomy and morphology as well as resting spore dimensions and arrangement, the symbiosis seems to be identical to the preceding observations in the Mediterranean. According to the phylogenetic analyses of the 18S rRNA gene, the phytomyxid represents the first characterized member of the environmental clade "TAGIRI-5". Our results provide new clues about its on-site ecology (incl. possible dispersal mechanisms), hint that it is rare but established in the Mediterranean, and encourage further research into its distribution, ecophysiology, and taxonomy.


Assuntos
Cercozoários/fisiologia , Hydrocharitaceae/parasitologia , Folhas de Planta/parasitologia , Simbiose , Cercozoários/classificação , Cercozoários/genética , Espécies Introduzidas , Itália , Mar Mediterrâneo , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
8.
Vet Parasitol Reg Stud Reports ; 18: 100327, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31796195

RESUMO

Diaphragm samples from 65 hunted sika deer (Cervus nippon yesoensis) from Hokkaido, Japan were examined for the presence of sarcocysts based on histological sections. Morphologically, the detected sarcocysts grouped into three types: (Type 1) 108.0-305.0 µm in width, thick-walled (4.3-7.0 µm) with tombstone-like protrusions; (Type 2) 25.0-69.5 µm in width, thick-walled (3.8-8.0 µm) with finger-like protrusions; and (Type 3) 22.5-55.0 µm in width, thin-walled (under 1 µm) with no visible protrusions under light microscopy. All samples contained at least one sarcocyst type, and multiparasitism was apparent in 58 samples. Morphologically, Type 1 sarcocysts were found in 19 (29.2%) samples, Type 2 in 62 (95.4%) samples, and Type 3 in 60 (92.3%) samples. The sarcocysts were collected using laser microdissection, the DNA extracted from them was PCR-amplified, and their 18S ribosomal RNA and cytochrome c oxidase subunit 1 genes were sequenced. Phylogenetic analysis showed that, for both genes, each morphological sarcocyst type (Types 1, 2, and 3) aligned most closely with S. silva/S. truncata, S. tarandi/S. elongata, and S. pilosa, respectively. Based on the sequence identities between taxa and the molecular information for sarcocysts in C. nippon centralis, the sarcocyst types were presumed to be S. truncata-like (Type 1), S. tarandi-like (Type 2), and S. pilosa (Type 3). The phylogenetic analyses based on the present comprehensive molecular characterization of three Sarcocystis spp. from C. nippon yesoensis in Hokkaido suggest that canids (e.g., wild foxes) may be the definitive hosts for S. pilosa, and felids (or unknown species) the definitive hosts for the other two species.


Assuntos
Cervos , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Sarcocystis/isolamento & purificação , Sarcocistose/veterinária , Animais , Diafragma/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/análise , Japão/epidemiologia , Filogenia , Prevalência , Proteínas de Protozoários/análise , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Sarcocystis/classificação , Sarcocystis/genética , Sarcocistose/epidemiologia , Sarcocistose/parasitologia
9.
Vet Parasitol Reg Stud Reports ; 18: 100323, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31796198

RESUMO

Cryptosporidium is an obligate intracellular protist parasite infecting a wide range of vertebrate hosts and causes significant intestinal disease in both animals and humans, as some species are zoonotic. Cattle and especially calves have been identified as one of the most common reservoirs of this protist. However, little is known about the genetics of Cryptosporidium in calves in some regions of France. The aim of this study was to detect and isolate Cryptosporidium spp. in faecal samples from naturally infected pre-weaned calves (≤45 days-old) in France. A total of 35 diarrhoeic pre-weaned calf faecal samples were collected from 26 dairy cattle farms in six departments (French administrative provinces). Cryptosporidium presence was established by microscopically screening samples for oocystes with an immunofluorescent (DFA) staining method. DFA-positive samples were then analysed by PCR-RFLP and 18S rRNA gene sequencing to determine species. Cryptosporidium parvum-positive samples were subtyped via nested PCR analysis of a partial fragment of the 60 kDa glycoprotein (gp60) gene product. Data were then integrated into phylogenetic tree analysis. DFA revealed the presence of Cryptosporidium oocysts in 31 out of 35 (88%) samples. Combined with 18S rRNA gene analysis results, C. parvum was detected in 30 samples. Subtyping analysis in 27/30 samples (90%) of the C. parvum isolates revealed two zoonotic subtype families, IIa (24/27) and IId (3/27). Four subtypes were recognised within the subtype family IIa, including the hypertransmissible IIaA15G2R1 subtype that is the most frequently reported worldwide (21/27), IIaA17G3R1 (1/27), IIaA17G1R1 (1/27), and IIaA19G1R1 (1/27). Two subtypes were recognised within the IId subtype family including IIdA22G1 (2/27) and IIdA27G1 (1/27). These findings illustrate the high occurrence of Cryptosporidium in calves in dairy herds and increase the diversity of molecularly characterised C. parvum isolates with the first description of IIaA17G3R1, IIaA19G1R1, and IId subtypes in France. The presence of zoonotic C. parvum subtype families (IIa, IId) in this study suggests that pre-weaned calves are likely to be a significant reservoir of zoonotic C. parvum, and highlights the importance of animal to human cryptosporidiosis transmission risk. Further molecular studies in calves and small ruminants from other French regions are required to better understand the epidemiology of cryptosporidiosis in France.


Assuntos
Doenças dos Bovinos/epidemiologia , Cryptosporidium/genética , Reservatórios de Doenças/veterinária , Zoonoses/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , Reservatórios de Doenças/parasitologia , Fezes/parasitologia , França/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Prevalência , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Zoonoses/parasitologia
10.
Sci Rep ; 9(1): 16360, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704993

RESUMO

The ciliate genus Spirostomum comprises eight morphospecies, inhabiting diverse aquatic environments worldwide, where they can be used as water quality indicators. Although Spirostomum species are relatively easily identified using morphological methods, the previous nuclear rDNA-based phylogenies indicated several conflicts in morphospecies delineation. Moreover, the single locus phylogenies and previous analytical approaches could not unambiguously resolve phylogenetic relationships among Spirostomum morphospecies. Here, we attempt to investigate species boundaries and evolutionary history of Spirostomum taxa, using 166 new sequences from multiple populations employing one mitochondrial locus (CO1 gene) and two nuclear loci (rRNA operon and alpha-tubulin gene). In accordance with previous studies, relationships among the eight Spirostomum morphospecies were poorly supported statistically in individual gene trees. To overcome this problem, we utilised for the first time in ciliates the Bayesian coalescent approach, which accounts for ancestral polymorphisms, incomplete lineage sorting, and recombination. This strategy enabled us to robustly resolve deep relationships between Spirostomum species and to support the hypothesis that taxa with compact macronucleus and taxa with moniliform macronucleus each form a distinct lineage. Bayesian coalescent-based delimitation analyses strongly statistically supported the traditional morphospecies concept but also indicated that there are two S. minus-like cryptic species and S. teres is non-monophyletic. Spirostomum teres was very likely defined by a set of ancestral features of lineages that also gave rise to S. yagiui and S. dharwarensis. However, molecular data from type populations of the morphospecies S. minus and S. teres are required to unambiguously resolve the taxonomic problems.


Assuntos
Cilióforos/classificação , Cilióforos/genética , DNA Ribossômico/análise , Macronúcleo/genética , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Animais , Teorema de Bayes , Análise de Sequência de DNA , Especificidade da Espécie
11.
Malar J ; 18(1): 350, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619258

RESUMO

BACKGROUND: Malaria elimination requires diagnostic methods able to detect parasite levels well below what is currently possible with microscopy and rapid diagnostic tests. This is particularly true in surveillance of malaria at the population level that includes so-called "asymptomatic" individuals. METHODS: The development of the first ultrasensitive loop mediated amplification method capable of detecting malaria from both whole blood and dried blood spots (DBS) is described. The 18S rRNA and corresponding genes that remain stable on DBS for up to 5 months are targeted. RESULTS: In the case of Plasmodium falciparum, lower limits of detection of 25 parasite/mL and 50-100 parasite/mL from whole blood and DBS were obtained, respectively. A sensitivity of 97.0% (95% CI 82.5-99.8) and specificity of 99.1% (95% CI 97.6-99.7) was obtained for the detection of all species in asymptomatic individuals from Africa and Asia (n = 494). CONCLUSION: This tool is ideally suited for low middle-income countries where malaria is endemic and ultrasensitive surveillance of malaria is highly desirable for elimination.


Assuntos
Teste em Amostras de Sangue Seco , Técnicas de Amplificação de Ácido Nucleico/métodos , Plasmodium falciparum/isolamento & purificação , Testes Diagnósticos de Rotina , Malária Falciparum/prevenção & controle , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Fatores de Tempo
12.
Parasitol Int ; 73: 101975, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31421267

RESUMO

This work reports the occurrence of coccidia of the genus Calyptospora in fishes from the eastern Amazon. Fish were collected on flood plains in the municipality of Macapá, State of Amapá, Brazil. Fresh squash preparations of liver, heart and gallbladder were examined under light microscope. Positive samples of Geophagus proximus and Hoplias malabaricus were used to detect parasites by PCR with Calyptospora-specific primers mRF and mrR, which amplify a region of the 18S rRNA gene. Oocysts were observed in 55% of 130 fishes examined. Parasite prevalence varied according to feeding habits, and was 100% in carnivores, 74% in omnivores (invertivores and detritivores) and 0% in herbivores. Variation in the frequency of parasitized organs showed 100% in the liver, 30% in the gallbladder, and 9% in the heart. The sequences obtained from G. proximus and H. malabaricus were identical and showed 99% similarity to Calyptospora serrasalmi. To our knowledge, this is the first report of the occurrence of Calyptospora in 10 new species of fish from the region of the eastern Brazilian Amazon. The results demonstrate the occurrence of C. serrasalmi in the region and the research provides new primers for the diagnosis of Calyptospora spp.


Assuntos
Coccidiose/veterinária , Eucoccidiida/isolamento & purificação , Doenças dos Peixes/epidemiologia , Peixes , Animais , Brasil , Caraciformes , Ciclídeos , Coccidiose/epidemiologia , Coccidiose/parasitologia , Dieta , Doenças dos Peixes/parasitologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
13.
Ticks Tick Borne Dis ; 10(6): 101262, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31327745

RESUMO

We report a case of severe babesiosis caused by the bovine pathogen Babesia divergens with the development of multisystem failure in a splenic host. Immunosuppression other than splenectomy can also predispose people to B. divergens. There was heavy multiple invasion of up to 14 parasites inside the erythrocyte, which had not been previously observed even in asplenic hosts. The piroplasm 18S rRNA sequence from our patient was identical B. divergens EU lineage with identity 99.5-100%.


Assuntos
Babesia/isolamento & purificação , Babesiose/diagnóstico , Baço/parasitologia , Idoso , Babesia/classificação , Babesiose/fisiopatologia , Eritrócitos/parasitologia , Evolução Fatal , Feminino , Humanos , Moscou , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
14.
PLoS Negl Trop Dis ; 13(6): e0007398, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31206518

RESUMO

BACKGROUND: Giardia lamblia is a very common cause of gastrointestinal symptoms worldwide. There are several methods for the diagnosis of Giardia infection, however none are ideal. We aim to find a new, microRNA-based method that will improve the currently available diagnostic methods for giardiasis. METHODS: Deep-sequence profiling of Giardia small-RNA revealed that miR5 and miR6 are highly expressed in Giardia. These miRNAs were tested by qRT-PCR in duodenal biopsies of patients with giardiasis who were positive by microscopic pathological evaluation. The gastric biopsies of the same patients served as negative control tissues. Additionally, these miRNAs were evaluated in stool samples of patients with proven giardiasis. RESULTS: All histologically proven duodenal biopsies of patients with Giardia infection were positive for Giardia miR5, with a mean threshold cycle (Ct) of 23.7, as well as for Giardia DNA qPCR (16S-like gene, mean Ct 26.3). Gastric biopsies which were tested as a control all were negative. Stool evaluation of miR6 in patients with giardiasis showed 90% specificity but only 66% sensitivity, and a lower accuracy rate was obtained with miR5. CONCLUSION: Giardia miR5 testing in duodenal biopsies may be a new method for the diagnosis of giardiasis. It seems to be more sensitive when compared with testing for Giardia DNA by qPCR in duodenal biopsies. It will be important to investigate the contribution of routine Giardia miRNA testing in duodenal biopsies from patients with persistent abdominal symptoms.


Assuntos
Duodeno/parasitologia , Fezes/parasitologia , Giardia lamblia/genética , Giardíase/diagnóstico , MicroRNAs/análise , RNA de Protozoário/análise , Biópsia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Sensibilidade e Especificidade
15.
J Eukaryot Microbiol ; 66(6): 869-881, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30977159

RESUMO

The biodiversity of peritrich ciliates from brackish biotopes is rarely investigated, especially members of the genus Pseudovorticella. Here, the morphology of three species of Pseudovorticella, i.e. P. cf. vestita (Stokes, 1883) Jankowski, 1976, P. spathulata sp. n., and P. qinghaiensis sp. n. isolated from brackish waters were studied. Pseudovorticella cf. vestita is characterized by inverted bell-shaped cell; a J-shaped macronucleus; a single contractile vacuole ventrally located; P3 three-rowed; pellicle striated with highly developed pellicular vesicles; 18-22 transverse silverlines between peristome and aboral trochal band, and 9-13 between aboral trochal band and scopula. Pseudovorticella spathulata sp. n. differs from its congeners by the following combination of characters: elongate-elliptical cell; a single contractile vacuole near ventral wall of infundibulum; a J-shaped macronucleus; P3 three-rowed; 24-34 silverlines between oral area and aboral trochal band and 6-10 between aboral trochal band and scopula. Pseudovorticella qinghaiensis sp. n. is characterized by: cell with an oval outline; a single contractile vacuole near ventral wall of infundibulum; a C-shaped macronucleus; P3 three-rowed; 30-35 and 9-11 transverse silverlines above and below the trochal band, respectively. The SSU rDNA sequences of five Pseudovorticella species, namely P. annulata, P. monilata, P. parakenti, P. spathulata sp. n., and P. cf. vestita, plus that of Zoothamnium hartwigi, are reported for the first time and their evolutionary relationships are investigated. Five undefined Pseudovorticella forms are considered might be conspecific with P. monilata. Two congeners are conspecific with P. spathulata sp. n. Phylogenetic analyses based on SSU rDNA sequences reveal that Pseudovorticella is not monophyletic and Z. hartwigi clusters with its congeners as expected.


Assuntos
Lagos/parasitologia , Oligoimenóforos/classificação , Água do Mar/parasitologia , China , Oligoimenóforos/citologia , Oligoimenóforos/genética , Filogenia , RNA de Protozoário/análise , Águas Salinas , Áreas Alagadas
16.
J Eukaryot Microbiol ; 66(6): 882-891, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31033101

RESUMO

Holomastigotes is a protist genus (Parabasalia: Spirotrichonymphea) that resides in the hindguts of "lower" termites. It can be distinguished from other parabasalids by spiral flagellar bands that run along the entire length of the cell, an anterior nucleus, a reduced or absent axostyle, the presence of spherical vesicles inside the cells, and the absence of ingested wood particles. Eight species have been described based on their morphology so far, although no molecular data were available prior to this study. We determined the 18S rRNA gene sequences of Holomastigotes from the hindguts of Hodotermopsis sjostedti, Reticulitermes flavipes, Reticulitermes lucifugus, and Reticulitermes tibialis. Phylogenetic analyses placed all sequences in an exclusive and well-supported clade with the type species, Holomastigotes elongatum from R. lucifugus. However, the phylogenetic position of Holomastigotes within the Spirotrichonymphea was not resolved. We describe two new species, Holomastigotes flavipes n. sp. and Holomastigotes tibialis n. sp., inhabiting the hindguts of R. flavipes and R. tibialis, respectively.


Assuntos
Isópteros/parasitologia , Parabasalídeos/classificação , Animais , Sistema Digestório/parasitologia , Parabasalídeos/citologia , Parabasalídeos/genética , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Simbiose
17.
Protist ; 170(1): 82-103, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30797136

RESUMO

Perkinsozoa is an exclusively parasitic group within the alveolates and infections have been reported from various organisms, including marine shellfish, marine dinoflagellates, freshwater cryptophytes, and tadpoles. Despite its high abundance and great genetic diversity revealed by recent environmental rDNA sequencing studies, Perkinsozoa biodiversity remains poorly understood. During the intensive samplings in Korean coastal waters during June 2017, a new parasitoid of dinoflagellates was detected and was successfully established in culture. The new parasitoid was most characterized by the presence of two to four dome-shaped, short germ tubes in the sporangium. The opened germ tubes were biconvex lens-shaped in the top view and were characterized by numerous wrinkles around their openings. Phylogenetic analyses based on the concatenated SSU and LSU rDNA sequences revealed that the new parasitoid was included in the family Parviluciferaceae, in which all members were comprised of two separate clades, one containing Parvilucifera species (P. infectans, P. corolla, and P. rostrata), and the other containing Dinovorax pyriformis, Snorkelia spp., and the new parasitoid from this study. Based on morphological, ultrastructural, and molecular data, we propose to erect a new genus and species, Tuberlatum coatsi gen. n., sp. n., from the new parasitoid found in this study. Further, we examined and discussed the validity of some diagnostic characteristics reported for parasitoids in the family Parviluciferaceae at both the genus and species levels.


Assuntos
Alveolados/classificação , Alveolados/fisiologia , Dinoflagelados/parasitologia , Alveolados/citologia , Alveolados/ultraestrutura , Dinoflagelados/citologia , Dinoflagelados/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Filogenia , RNA de Algas/análise , RNA de Protozoário/análise , República da Coreia , Análise de Sequência de RNA
18.
J Eukaryot Microbiol ; 66(4): 637-653, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30620427

RESUMO

Microbial eukaryotes have important roles in marine food webs, but their diversity and activities in hydrothermal vent ecosystems are poorly characterized. In this study, we analyzed microbial eukaryotic communities associated with bacterial (Beggiatoa) mats in the 2,000 m deep-sea Guaymas Basin hydrothermal vent system using 18S rRNA gene high-throughput sequencing of the V4 region. We detected 6,954 distinct Operational Taxonomic Units (OTUs) across various mat systems. Of the sequences that aligned with known protistan phylotypes, most were affiliated with alveolates (especially dinoflagellates and ciliates) and cercozoans. OTU richness and community structure differed among sediment habitats (e.g. different mat types and cold sediments away from mats). Additionally, full-length 18S rRNA genes amplified and cloned from single cells revealed the identities of some of the most commonly encountered, active ciliates in this hydrothermal vent ecosystem. Observations and experiments were also conducted to demonstrate that ciliates were trophically active and ingesting fluorescent bacteria or Beggiatoa trichomes. Our work suggests that the active and diverse protistan community at the Guaymas Basin hydrothermal vent ecosystem likely consumes substantial amounts of bacterial biomass, and that the different habitats, often defined by distances of just a few 10s of cm, select for particular assemblages and levels of diversity.


Assuntos
Alveolados/isolamento & purificação , Cercozoários/isolamento & purificação , Fontes Hidrotermais/microbiologia , Microbiota , Água do Mar/microbiologia , Alveolados/genética , Beggiatoa/fisiologia , Cercozoários/genética , México , RNA de Protozoário/análise , RNA Ribossômico 18S/análise
19.
Malar J ; 18(1): 26, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683099

RESUMO

BACKGROUND: The transcriptional regulation that occurs in malaria parasites during the erythrocytic stages of infection can be studied in vivo with rodent malaria parasites propagated in mice. Time-series transcriptome profiling commonly involves the euthanasia of groups of mice at specific time points followed by the extraction of parasite RNA from whole blood samples. Current methodologies for parasite RNA extraction involve several steps and when multiple time points are profiled, these protocols are laborious, time-consuming, and require the euthanization of large cohorts of mice. RESULTS: A simplified protocol has been designed for parasite RNA extraction from blood volumes as low as 20 µL (microsamples), serially bled from mice via tail snips and directly lysed with TRIzol reagent. Gene expression data derived from microsampling using RNA-seq were closely matched to those derived from larger volumes of leucocyte-depleted and saponin-treated blood obtained from euthanized mice with high reproducibility between biological replicates. Transcriptome profiling of microsamples taken at different time points during the intra-erythrocytic developmental cycle of the rodent malaria parasite Plasmodium vinckei revealed the transcriptional cascade commonly observed in malaria parasites. CONCLUSIONS: Microsampling is a quick, robust and cost-efficient approach to sample collection for in vivo time-series transcriptomic studies in rodent malaria parasites.


Assuntos
Sangue/parasitologia , Eritrócitos/parasitologia , Perfilação da Expressão Gênica/métodos , Plasmodium/isolamento & purificação , RNA de Protozoário/análise , Animais , Feminino , Perfilação da Expressão Gênica/economia , Perfilação da Expressão Gênica/instrumentação , Malária/sangue , Malária/parasitologia , Camundongos , Camundongos Endogâmicos CBA , Plasmodium chabaudi/isolamento & purificação , Reprodutibilidade dos Testes
20.
J Eukaryot Microbiol ; 66(1): 120-139, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29791056

RESUMO

We report the discovery of a new genus of heterolobosean flagellates, Dactylomonas gen. nov., with two species, D. venusta sp. nov. and D. crassa sp. nov. Phylogenetic analysis of the SSU rRNA gene showed that Dactylomonas is closely related to the amoeba Selenaion, the deepest-branching lineage of Tetramitia. Dactylomonads possess two flagella, and ultrastructural studies revealed an unexpected organization of the flagellar apparatus, which resembled Pharyngomonada (the second lineage of Heterolobosea) instead of Tetramitia: basal bodies were orthogonal to each other and a putative root R1 was present in the mastigont. On the other hand, Dactylomonas displayed several features uncommon in Heterolobosea: a microtubular corset, a distinctive rostrum supported by the main part of the right microtubular root, a finger-like projection on the proximal part of the recurrent flagellum, and absence of a ventral groove. In addition, Dactylomonas is anaerobic and seems to have lost mitochondrial cristae. Dactylomonas and Selenaion are accommodated in the family Selenaionidae fam. nov. and order Selenionida ord. nov. The taxonomy of Tetramitia is partially revised, and the family Neovahlkampfiidae fam. nov. is established.


Assuntos
Classificação , Lobosea/classificação , RNA de Protozoário/análise , Lobosea/citologia , Lobosea/genética , Lobosea/ultraestrutura , Filogenia
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