Hosts have evolved a multiplicity of defensive responses against avian brood parasites. One of them is mobbing behaviour which often includes direct contact attacks. These aggressive strikes may not only distract the parasites but may also be fatal to them, as documented by cases of dead brood parasite females found near host nests. Here, we present the first video-recording of a great reed warbler (Acrocephalus arundinaceus) host whose vigorous nest defence appears to directly lead to the death of a female common cuckoo (Cuculus canorus). We suggest that the chance of parasite death probably rises with the presence of unfavourable factors, such as water below the nest. Our observation supports previous suggestions that hosts may pose a lethal danger to their parasites.
A new myxozoan, Ceratomyxa bohari sp. n., infecting the gall bladder of two-spot red snapper, Lutjanus bohar Forsskål, in the Red Sea off Saudi Arabia, is described using light microscopy and characterised genetically. The infection was recorded as mature spores floating free in the bile. The overall prevalence of infection of the type host was 19% (67 fish infected of 360 examined), with the highest prevalence in autumn (31%; 28/90) and the lowest in winter at 12% (11/90). Mature spores are slender and slightly crescent-shaped in the frontal view, with anterior and posterior margins tapered gradually to rounded valvular tips. Spore valves are unequal with a prominent sutural line. The spore dimensions are 3-4 μm (mean 3.5 μm) in length and 16-19 μm (mean 17 μm) in thickness. Two polar capsules are spherical, equal in size, 1.5 μm in diameter. Coils of the polar filament are indiscernible. The sporoplasm is binucleated and fills nearly one third of the extracapsular space restricted to the area below the capsules. The molecular analysis based on the small subunit rDNA (SSU rDNA) sequence revealed a close relationship with majority of species of Ceratomyxa Thélohan, 1892 and phylogenetic clustering with species from different geographical location. Thus, the shorter spore of the present Ceratomyxa species and the divergence of the SSU rDNA sequences were the distinctive features that separate it from all previously described species and identified this parasite as a new species of Ceratomyxa., Lamjed Mansour, Abdel-Azeem S. Abdel-Baki, Ahmad F. Tamihi, Saleh Al-Quraishy., and Obsahuje bibliografii
Polymorphic microsatellite loci were characterised for two louse species, the anopluran Polyplax serrata Burmeister, 1839, parasitising Eurasian field mice of the genus Apodemus Kaup, and the amblyceran Myrsidea nesomimi Palma et Price, 2010, found on mocking birds endemic to the Galápagos Islands. Evolutionary histories of the two parasites show complex patterns influenced both by their geographic distribution and through coevolution with their respective hosts, which renders them prospective evolutionary models. In P. serrata, 16 polymorphic loci were characterised and screened across 72 individuals from four European populations that belong to two sympatric mitochondrial lineages differing in their breadth of host-specificity. In M. nesomimi, 66 individuals from three island populations and two host species were genotyped for 15 polymorphic loci. The observed heterozygosity varied from 0.05 to 0.9 in P. serrata and from 0.0 to 0.96 in M. nesomimi. Deviations from the Hardy-Weinberg equilibrium were frequently observed in the populations of both parasites. Fst distances between tested populations correspond with previous phylogenetic data, suggesting the microsatellite loci are an informative resource for ecological and evolutionary studies of the two parasites., Jana Martinů, Veronika Roubová, Milena Nováková, Vincent S. Smith, Václav Hypša, Jan Štefka., and Obsahuje bibliografii
The aim of the present study was to estimate the genetic diversity of the cestode Echinococcus multilocularis Leuckart, 1863 in Poland based on sequence analysis of the mitochondrial genes of worms isolated from red foxes, Vulpes vulpes (Linnaeus). Overall, 83 adults of E. multilocularis from the same number of foxes in different parts of Poland were used for analysis. Sequences of the three mitochondrial genes, cytochrome b (cob), NADH dehydrogenase subunit 2 (nad2) and cytochrome c oxidase subunit 1 (cox1), were analysed. Seventy-four individual biological samples were successfully sequenced. Combined sequence analysis of these three genes exhibited fifteen Polish haplotypes (EmPL1-EmPL15). Most isolates (n = 29; 39%) were classified to the EmPL1 haplotype, which occurred mainly in the east, north and centre of Poland. Haplotype EmPL4 (n = 14; 19%) and other haplotypes appeared predominantly in the south and west area. Fourteen haplotypes were grouped in the European clade. One Polish haplotype (EmPL9) (n = 7, 10%) was assigned to the Asian clade with haplotypes from Japan and Kazakhstan. This haplotype was found only in northeast Poland and this is the westernmost report of haplotype of E. multilocularis belonging to the Asian clade in Europe. The investigation demonstrated that populations of E. multilocularis in Poland (and probably also in eastern Europe) included not only different European haplotypes but also those of the Asian origin., Jacek Karamon, Krzysztof Stojecki, Małgorzata Samorek-Pieróg, Ewa Bilska-Zajac, Mirosław Rózycki, Ewa Chmurzyńska, Jacek Sroka, Jolanta Zdybel, Tomasz Cencek., and Obsahuje bibliografii
Knowledge of blood parasites in Brazilian chelonians is limited, since they have been recorded in only six species. Mesoclemmys vanderhaegei (Bour) is a freshwater turtle with a wide geographic distribution in Brazil, but there is little information about its natural history. This paper reports on a study of the prevalence and infection intensity of a haemogregarine in two subpopulations of M. vanderhaegei. The study was conducted in two areas of Cerrado in the Upper Paraguay River basin in the state of Mato Grosso, Brazil, between November 2010 and August 2013. Ninety-five (53%) of the 179 turtles captured were positive for haemogregarine parasites. The parasitic forms observed were two morphotypes of intraerythrocytic gametocytes. The prevalence differed between size classes, increasing significantly according to the animals' body size. There was no significant difference between prevalence and sex, or between sampling periods. The mean parasite intensity was 9 parasites/2,000 erythrocytes (0.45%) and the parasite population presented an aggregated distribution, with an aggregation index of 19 and discrepancy of 0.772. This is the first record of a hemoparasite in the freshwater turtle M. vanderhaegei., Vinícius C. Goes, Elizângela S. Brito, Rafael M. Valadão, Camila O. Gutierrez, Amanda M. Picelli, Lúcio A. Viana., and Obsahuje bibliografii
Hereditary haemorrhagic telangiectasia (HHT) exhibits considerable phenotypic heterogeneity. Therefore, precise mutation screening and evaluation of patient risk must be determined in every HHT family. We present an HHT-2 case with an initial life-threatening bleeding episode that led to identification of a relatively large HHT family. Exome sequencing of the family members determined HHT-associated ACVRL1C1120T variant resulting in Arg374Trp substitution at the Ser/Thr-kinase domain region. The affected members display typical epistaxis symptomatology from early childhood resulting in sideropoenia. In addition, the HHT patients also displayed dermatology findings such as facial teleangiectasias and trunk/limb white spots representing post-inflammatory hypopigmentation. Interestingly, co-segregating with modifying cytochrome P450 (CYP2C) variant in the HHT patients led to NSAID intolerance marked by increased frequency of bleeding episodes. No arterial-venous malformation of the visceral organs and brain or association with cancer were observed. The heterogeneity of clinical presentation and the role of other variants support the need of regular patient monitoring and development of a nation-wide patient registry.
Parasite life history traits influence the rate of gene flow between populations and the effective population size, both of which determine the levels of genetic variability and the geographic distribution of such variability. In this short review targeted to parasitologists, we summarise how life history traits influence the population genetic structure of parasitic helminths. These organisms are characterised by a wide variety of life cycles and are ecologically different from microparasites, which have been studied in more detail. In order to provide the reader a concise review that illustrates key aspects of the subject matter, we have limited ourselves to studying examples selected for their clarity and relevance., Severo Vázquez-Prieto, Román Vilas, Esperanza Paniagua, Florencio M. Ubeira., and Obsahuje bibliografii
The K13 propeller domain mutation and pfmdr1 amplification have been proposed as useful molecular markers for detection and monitoring of artemisinin resistant Plasmodium falciparum Welch, 1897. Genomic DNA isolates of P. falciparum was extracted from 235 dried blood spot or whole blood samples collected from patients with uncomplicated falciparum malaria residing in areas along the Thai-Myanmar border during 2006-2010. Nested polymerase chain reaction (PCR) and sequencing were performed to detect mutations in K13 propeller domain of P. falciparum at codon 427-709. Pfmdr1 gene copy number was determined by SYBR Green I real-time PCR. High prevalence of pfmdr1 multiple copies was observed (42.5% of isolates). The presence of K13 mutations was low (40/235, 17.2%). Seventeen mutations had previously been reported and six mutations were newly detected. The C580Y was found in two isolates (0.9%). The F446I, N458Y and P574L mutations were commonly detected. Seven isolates had both K13 mutation and pfmdr1 multiple copies. It needs to be confirmed whether parasites harbouring both K13 mutation and pfmdr1 multiple copies and/or the observed new mutations of K13 propeller domain are associated with clinical artemisinin resistance., Papichaya Phompradit, Wanna Chaijaroenkul, Phunuch Muhamad, Kesara Na-Bangchang., and Obsahuje bibliografii
Toxoplasmosis is a potentially fatal complication after hematopoietic cell transplantation (HCT). Pre-transplant seropositivity of graft recipient to Toxoplasma gondii (Nicolle et Manceaux, 1908) is an important factor for disease reactivation after HCT. As toxoplasmosis epidemiology varies all over the world, we performed a Polish nationwide retrospective cohort study to determine the seroprevalence of toxoplasmosis in donors and pediatric allogeneic and autologous HCT recipients and the incidence of clinically evident toxoplasmosis in this patient group. Polish adult donors had higher anti-T. gondii seroprevalence than Polish pediatric donors (28% vs 8%; OR = 4.4; p = 0.02) and allo-HCT recipients (28% vs 17%; OR = 1.9; p = 0.01). Clinically apparent disease occurred in 1% of allo-HCT recipients: it was diagnosed by PCR as cerebral and/or ocular toxoplasmosis and successfully treated with antiprotozoal therapy. Regarding current practice, no prospective screening for infection of T. gondii in pediatric HCT centres is being performed, but, vast majority of HCT pediatric patients are receiving anti-T. gondii active prophylaxis. Since pre-HCT T. gondii serology was not assessed in all HCT; recipients, we propose this test should be a standard practice. Standardisation of management with infection of T. gondii in children after HCT is needed.
Microcercous cercariae possess a very short tail and are produced by digenean species of several families including medically important species, such as members of the genera Paragonimus Braun, 1899, Nanophyetus Chapin, 1927 and Troglotrema Odhner, 1914. During our survey of cercariae of Paragonimus spp. in Vietnam, we found microcercous cercariae from ten (0.29%) out of 3,400 snails of Triculinae gen. sp. 2. They were morphologically and molecularly analysed for species identification. The molecular analysis, based on ITS2 sequences, revealed two distinct species: four specimens were identical to Paragonimus proliferus Hsia et Chen, 1964 (Paragonimidae Dollfus, 1939), and the other six specimens were closest to members of the family Troglotrematidae Odhner, 1914 and were temporarily named Troglotrematidae gen. sp. Morphologically, cercariae of the two species found in this study are similar to each other in their gross characteristics but can be distinguished from one another by subtle morphological details. The cercaria of P. proliferus has an I-shaped excretory bladder and does not have mucous gland cells. In contrast, that of Troglotrematidae gen. sp. has a Y-shaped excretory bladder and mucous gland cells. Besides, the redia of P. proliferus is elongate with a short intestine and contains 5-6 cercariae whereas that of Troglotrematidae gen. sp. is more round with a longer intestine and harbours 3-4 cercariae. Our results have shown the importance of the shape of the excretory bladder and the presence/absence of mucous gland cells of the cercaria as well as the shape and size of the redia, and its intestinal length as valuable taxonomic characters of intramolluscan trematode larvae. In addition, the finding of similar microcercous cercariae of different species in the same snail species suggests that careful attention to morphological details is required in the differentiation of Paragonimus cercariae and those of closely related species., Pham Ngoc Doanh, Hoang Van Hien and Bui Thi Dung., and Obsahuje bibliografii