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The present paper reports for the first time on the occurrence of the parasite Maritrema subdolum in the amphipod Gammarus tigrinus, a non-native species in the Gulf of Gdańsk.
Parasitic weeds especially Phelipanche aegyptiaca decrease severely the production of canola. This study evaluated the effect of intercropping different wheat genotypes with canola on Phelipanche aegyptiaca growth. Ten wild wheat genotypes with different ploidy levels including TRI11712, TRI19322, TRI18664, TRI19652, TRI565, TRI15593, TRI12911, TRI11554, TRI17606, TRI7259P and seven cultivated bread wheats, namely: Falat, Chamran, Alamut, Baiat, Kavir, Sepahan, Alvand in addition to a canola cultivar called Zarfam were studied. The results revealed that intercropping of canola with wheat could significantly reduce broomrape growth depending on the type of wheat genotype. A significant genetic variation of allelopathic activity in wheat was observed, indicating the contribution of multiple genes conferring the allelopathic trait. TRI565 and TRI12911, TRI15593, TRI18664, TRI19652, TRI17606, TRI19322, and TRI7259 genotypes showed strong inhibitory effects and can be considered as potential allelopathic genotypes to suppress broomrape. The inhibitory potential of wild wheat genotypes was stronger than cultivated wheat genotypes. Alamut, Baiat, Alvand, Sepahan, and TRI11712 possessed strong stimulatory effects on broomrape germination. Such genotypes may be valuable as trap crops for depleting the Egyptian broomrape seed bank.
The objective of the study was to compare the usefulness of FLOTAC and centrifugal fecal flotation (CFF) techniques. More specifically, the taxonomic classes (Nematoda and Cestoda) of endoparasites present in fecal samples of buffaloes are identified, the sensitivity and specificity of FLOTAC relative to CFF are calculated, and the agreement of both techniques is evaluated using Kappa statistics. Fresh fecal samples from 220 buffaloes in 10 municipalities were collected. Sheather’s sugar was used as a flotation solution for both the FLOTAC and CFF techniques. Of the 220 animals, 109 samples were nematode positive and 111 samples were nematode negative according to the FLOTAC technique, while 74 were found to be positive and 146 negative according to the CFF technique. No cestodes were detected by either technique. The calculated sensitivity for FLOTAC is 89.19% and its specificity is 70.55%. Kappa statistics revealed moderate agreement (k=0.535) between the two techniques in detecting nematodes. The prevalence observed based on FLOTAC and CFF test were 49.54% (109/220; 95% CI: 47.75–56.34) and 33.64% (72/220; 95% CI: 27.42–40.3), respectively.
In this work we record the highest number of bat flies species among those already performed in the Brazilian cerrado and discuss the associations and patterns of parasitism of these species and their hosts. A total of 1,390 ectoparasitic flies were collected, belonging to 24 species of Streblidae and one of Nycteribiidae, parasitizing 227 bats of 15 species. Among the species found, the presence of Trichobius sp. on Lonchophylla mordax and the first occurrence of Hershkovitzia sp. on Thyroptera devivoi are highlighted. Lophostoma species presented the highest proportion of individuals with infracommunities and the highest values of parasitological indexes. The high number of bat fly species and hosts, as well as the high values for rates of parasitism and infracommunities, suggests that this area of cerrado has good shelter conditions for these species. The abundance of species and high rates of parasitism detracts from the hypothesis that a higher mean intensity of ectoparasites results from lower competition among flies for hosts in areas with lower ectoparasite species richness. Biogeographical and historical factors of host populations, besides the number of host species and individuals sampled, may contribute to species number and intensity of parasitism.
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Are all red algal parasites cut from the same cloth?

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Parasitism is a common life strategy throughout the eukaryotic tree of life. Many devastating human pathogens, including the causative agents of malaria and toxoplasmosis, have evolved from a photosynthetic ancestor. However, how an organism transitions from a photosynthetic to a parasitic life history strategy remains mostly unknown. This is largely because few systems present the opportunity to make meaningful comparisons between a parasite and a close free-living relative. Parasites have independently evolved dozens of times throughout the Florideophyceae (Rhodophyta), and often infect close relatives. The accepted evolutionary paradigm proposes that red algal parasites arise by first infecting a close relative and over time diversify and infect more distantly related species. This provides a natural evolutionary gradient of relationships between hosts and parasites that share a photosynthetic common ancestor. Elegant microscopic work in the late 20th century provided detailed insight into the infection cycle of red algal parasites and the cellular interactions between parasites and their hosts. Those studies led to the use of molecular work to further investigate the origins of the parasite organelles and reveal the evolutionary relationships between hosts and their parasites. Here we synthesize the research detailing the infection methods and cellular interactions between red algal parasites and their hosts. We offer an alternative hypothesis to the current dogma of red algal parasite evolution and propose that red algae can adopt a parasitic life strategy through multiple evolutionary pathways, including direct infection of distant relatives. Furthermore, we highlight potential directions for future research to further evaluate parasite evolution in red algae.
The evergreen, semi-parasitic pine mistletoe, Viscum album ssp. austriacum (Wiesb.) Volmann, is one of the four subspecies of European mistletoe, Viscum album L. It is frequently encountered on Scots pine communities in Poland. Distribution of pine mistletoe in representative P. sylvestris stand from the central Poland was investigated. The host density and host size to the frequency of Viscum was verified. Within the studied area 46% out of 313 individuals of P. sylvestris trees were infected by mistletoe, among them 78% in low mistletoe infection, 17% in medium and 3% in high infection. Of 1171 infections recorded on pines, 97% were on branches, 4% on the host trunk. The mistletoe individuals had an aggregated pattern of spatial distribution which was mainly explained by the host size. Infected trees are larger than uninfected ones, on average, and within the infected tree population, trees with mistletoe had higher number of dead branches than trees with none infection. Parasitized trees were more prevalent in low-density stands than in high-density stands. Mistletoes occurred mainly on the outer brunches within trees crowns.
This study describes the assemblage of ectoparasitic bat flies, their hosts, and parasitism rates in an Atlantic Forest area in southern Brazil. Bats were captured monthly for one year at two sites. We captured 95 bats belonging to nine species, but only Artibeus lituratus, Artibeus fimbriatus, Sturnira lilium (Phyllostomidae) and Myotis nigricans (Vespertilionidae) were found to be parasitized. The bat flies collected were: Streblidae — Paratrichobius longicrus (on A. lituratus) and Megistopoda aranea (on A. lituratus and A. fimbriatus), Megistopoda proxima (on S. lilium); Nycteribiidae — Basilia andersoni (on M. nigricans). Artibeus fimbriatus and S. lilium showed the highest values of parasite prevalence (60 and 35.7%, respectively) and mean intensities (1.9 and 2.1, respectively). Only two parasitized individuals of A. lituratus were found, resulting in the lowest local rate of parasite prevalence (2.6%) and mean intensity (1.0). This low rate may result from the use of ephemeral roosts in the area. The high values of frequency and number of flies per host on A. fimbriatus and S. lilium in relation to other studies could be explained by the low richness of bat flies here, and in turn, by low competition among fly species per host.
Helicosporidia are gut parasites of invertebrates. These achlorophyllous, non-photosynthetic green algae are the first reported to infect insects. Helicosporidia are members of the green algal class Trebouxiophyceae and are further related to the photosynthetic and non-photosynthetic genera Auxenochlorella and Prototheca, respectively, the latter of which can also turn to parasitism under opportunistic conditions. Molecular analyses suggest that Helicosporidia diverged from other photosynthetic trebouxiophytes less than 200 million years ago and that its adaptation to parasitism is therefore recent. In this minireview, we summarize the current knowledge of helicosporidian genomics. Unlike many well-known parasitic lineages, the Helicosporidium sp. organelle and nuclear genomes have lost surprisingly little in terms of coding content aside from photosynthesis-related genes. While the small size of its nuclear genome compared to other sequenced trebouxiophycean representatives suggests that Helicosporidium is going through a streamlining process, this scenario cannot be ascertained at this stage. Genome expansions and contractions have occurred independently multiple times in the green algae, and the small size of the Helicosporidium genome may reflect a lack of expansion from a lean ancestor state rather than a tendency towards reduction.
Ancylostoma ceylanicum belongs to a group of soil-transmitted helminths, which infect almost 576 mln people worldwide and are a major cause of anaemia and malnutrition. Upon contact with a permissive host, third-stage larvae (L3) residing in the environment become activated larvae (ssL3), a process associated with changes in the profile of gene expression. Ancylostoma secreted proteins (ASPs) are the major proteins secreted during larvae activation and play a crucial role in hookworm adaptation to parasitism. Here we report the cloning using RACE-PCR technique of three novel ASPs from the hookworm A. ceylanicum (Ace-asp-3, Ace-asp-4, and Ace-asp-5) and computational analysis of the protein sequences. All three proteins contain SCP (Sperm Coating Protein) domain characteristic for previously described ASP proteins. Real-time PCR analysis shows significant up-regulation of Ace-asp-3 and Ace-asp-5 expression in adult worms and correlated down-regulation in ssL3 larvae. On the other hand, expression of Ace-asp-4 was increased in ssL3 stages and decreased in adult parasites.
A high infestation of the monogenean Gussevia tucunarense in a cultivation of bujurqui-tucunare was reported. The prevalence was 100%. The mean intensity and abundance of the parasite was 164.4 of parasites per individual. This is the first report of a high infestation by G. tucunarense in C. semifasciatus cultured from the Peruvian Amazon.
Classification and identification of muscle-parasitizing didymozoids found in marine fish is difficult because of their novel parasitism and morphology. Recent sequence analysis has helped, but only seven sequences are available. Therefore, the usefulness of molecular methods for differentiation of muscle-parasitizing didymozoids, as well as genetic differences between the muscle and the other site-parasitizing didymozoids are quite unclear. In the present study, six unidentified didymozoid isolates from the trunk muscles of four marine fish species (Diagramma pictum, Plectorhinchus cinctus, Pagrus major and Cypselurus heterurus) were examined genetically using sequence analysis (18S rDNA, 28S rDNA, ITS-2 and coxI). All isolates were placed phylogenetically as a lineage independent of other site-parasitizing didymozoids at 18S rDNA, ITS-2 and coxI. They were grouped into three distinct lineages. The present and the previous unidentified or identified didymozoids from trunk muscles were found to differ clearly for every host species by sequence analysis, suggesting that muscle-parasitizing didymozoids are host-specific. This report is the first describing the molecular characteristics of muscle-parasitizing didymozoids by sequence analysis targeting the nuclear and mitochondrial DNA loci, which is proposed as a superior method for didymozoid differentiation.
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