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32. Soluble total antigen derived from Toxoplasma gondii RH strain prevents apoptosis, but induces anti-apoptosis in human monocyte cell line
- Creator:
- Rahimi, Hanieh Mohammad, Nemati, Sara, Alavifard, Helia, Baghaei, Kaveh, Mirjalali, Hamed, and Zali, Mohammad Reza
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Toxoplasma gondii, Soluble total antigen, Apoptosis, Mcl-1, and Bcl-2
- Language:
- English
- Description:
- Apoptosis plays crucial role in the pathogenesis of toxoplasmosis, as it limits further development of the disease. The current study aimed to investigate the effects of different concentrations of soluble total antigen (STAg) of Toxoplasma gondii (Nicolle et Manceaux, 1908) on the apoptotic and anti-apoptotic pathways. PMA-activated THP-1 cell line was sensed by T. gondii STAg and the expression patterns of caspase-3, -7, -8, -9, Bax, Bcl-2, and Mcl-1 genes were evaluated. The results showed statistically significant concentration-dependent overexpression of both Bcl-2 (P-value < 0.0001) and Mcl-1 (P-value = 0.0147). The cas-7 showed overexpression in all concentrations (P-value < 0.0001). The cas-3 was suppressed in concentrations 100, 80, and 40 µg, but statistically significant downregulated in concentrations 10 and 20 µg. The Bax was suppressed in concentrations 100 to 20 µg, while it slightly downregulated 1.42 fold (P-value = 0.0029) in concentration 10 µg. The expression of cas-8 and -9 was suppressed in all concentrations. Our results indicated that T. gondii STAg downregulated and suppressed apoptotic and upregulated anti-apoptotic pathways. The upregulation of cas-7 in this study may indicate the role of T. gondii STAg in activation of inflammatory responses.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
33. Some fixed point theorems in logarithmic convex structures
- Creator:
- Moazzen, Alireza, Cho, Yoel-Je, Park, Choonkil, and Eshaghi Gordji, Madjid
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- fixed point, logarithmic convex structure, and convex metric space
- Language:
- English
- Description:
- In this paper, we introduce the concept of a logarithmic convex structure. Let X be a set and D : X × X → [1, ∞) a function satisfying the following conditions: (i) For all x, y ∈ X, D(x, y) ≥ 1 and D(x, y) = 1 if and only if x = y. (ii) For all x, y ∈ X, D(x, y) = D(y, x). (iii) For all x, y, z ∈ X, D(x, y) ≤ D(x, z)D(z, y). (iv) For all x, y, z ∈ X, z ≠ x, y and λ ∈ (0, 1), D(z, W(x, y, λ)) ≤ D λ (x, z)D 1−λ (y, z), D(x, y) = D(x, W(x, y, λ))D(y, W(x, y, λ)), where W : X ×X ×[0, 1] → X is a continuous mapping. We name this the logarithmic convex structure. In this work we prove some fixed point theorems in the logarithmic convex structure.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
34. Stomatocystis goerresi, a new species of gregarine parasite (Apicomplexa, Monocystidae) from the invasive Japanese earthworm Amynthas tokioensis (Megascolecidae), with a description of the parasite's life cycle
- Creator:
- Schall, Joseph J.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- protist, standardised diagnostic morphology, introduced species, and host specificity
- Language:
- English
- Description:
- Stomatocystis goerresi sp. n., a gregarine (phylum Apicomplexa, Monocystidae) parasite of an important invasive earthworm in North America, Amynthas tokioensis (Beddard), is described. This is the second species placed into the genus, and details of its morphology and life cycle support Stomatocystis Bandyopadhyay, Mitra et Göçmen, 2006 as a valid taxon. The new species is described using standard nomenclature, measurements, shape descriptors, and photographs of living cells. The parasite was found only in A. tokioensis, and absent in sympatric earthworm species, suggesting it arrived when the earthworms were introduced from their origin from Japan. The species is distinctive from the type species in the genus, S. indica Bandyopadhyay, Mitra et Göçmen, 2006, in being substantially larger in all stages, found in only the host's seminal vesicles, and found in a different host species from East Asia. The distinctive trophozoites/gamonts develop a large funnel structure ringed with a collar of pronounced ridges, and the funnel appears even in the smallest cells. This funnel varies greatly in relative size (to the cell body) and shape, sometimes forming a large fan. The life cycle of S. goerresi is described including distinctive syzygy in which the funnels fuse and then produce a large cell with local centres of isogamete production (thus sex without gender). Gametes are large ( ~5 μm) spheres with complex tips. Oocyst production is large, > 1,000 per mature gametocyst. The genus Stomatocystis is placed into the Monocystidae, but the life cycle of the new species differs from those of other monocystid taxa, which may mean the Monocystidae are not monophyletic or life cycles are variable within the family. Prevalence of S. goerresi at the type locality was high (~ 90%). The parasites destroy the earthworm's organ of sperm self-storage thus eliminating the male function in the hermaphroditic host which may influence the ability of the earthworm to invade and be successful at new sites
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
35. Survey of Kudoa spp. (Myxozoa, Cnidaria) in fishes from the Madeira Archipelago and the Portuguese mainland coast: detection of Kudoa thyrsites in new hosts Scomber colias and Micromesistius poutassou
- Creator:
- Cavaleiro, Bárbara, Serrão, Joana, Nogueira, Sara, Ribeiro, Liliana, Hermida, Margarida, Cruz, Cristina, Lisnerová, Martina, Fiala, Ivan, and Saraiva, Aurélia
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Atlantic, food safety, parasites, Portugal, scombrid, tuna, Atlantic chub mackerel, and blue whiting
- Language:
- English
- Description:
- Myxozoan parasites of the genus Kudoa Meglitsch, 1947 are associated with post-mortem tissue degradation that causes great financial losses to commercial fisheries. Kudoa thyrsites (Gilchrist, 1924) is a species with a very wide host range including commercial tunas, mackerels, salmonids and flatfishes. A sample of 190 fishes of 18 species from the Madeira Archipelago and 30 Atlantic chub mackerel, Scomber colias Gmelin, and 30 blue whiting, Micromesistius poutassou (Risso), from the Portuguese mainland coast were examined for the presence of species of Kudoa. The prevalence of Kudoa spp. was 80% in M. poutassou and 60% in S. colias. No spore was detected in S. colias from Madeira, which was confirmed by specific PCR screening of the muscle from all individuals of S. colias. SSU rDNA analysis revealed that M. poutassou and S. colias from the Portuguese mainland coast were infected with K. thyrsites, an economically important myxozoan parasite. Both sequences were identical with sequences of the eastern Atlantic K. thyrsites genotype, including that from the type host of this parasite. This is the first report of K. thyrsites from M. poutassou and S. colias. The fact that spores of species of Kudoa were not detected in fishes screened in the Madeira Archipelago may be explained by various ecological factors, such as the absence of a continental shelf, a short insular shelf, and oceanic waters with low productivity, all resulting in reduced abundance of benthic organisms. Consequently, it is possible that as yet unknown annelid definitive hosts of Kudoa spp. are absent or very rare near Madeiran coasts.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
36. Tadpoles in the diet of otters - an overlooked prey item in the diet of a riparian predator?
- Creator:
- Zalewska, Karolina , Zalewski, Andrzej , Wajrak, Adam , and Selva, Nuria
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- predator diet composition, Lutra lutra, and amphibians
- Language:
- English
- Description:
- Understanding the diets of predators, prey selection and their impact on prey populations is pivotal to investigations on the ecology of predator and prey species. In this study, we observed a hand-reared European otter (Lutra lutra) foraging in the wild, in order to identify the type of prey captured by the predator. The study was carried out between March and June 2001 in a diverse range of natural otter habitats in Białowieża Forest (NE Poland). We found that tadpoles represented an important part of the otter's diet in June, when their frequency of occurrence and biomass reached 38% and 11%, respectively. During spring, tadpoles were less common than other types of prey, such as adult amphibians, fish, or aquatic Coleoptera. Otter diet varied among months and there were differences in the main prey type captured among water body types. Our results highlight the need to develop methods that enable the identification of tadpoles and other cryptic seasonal food items in riparian predator diets.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
37. The Crimean population of the lesser grey shrike (Lanius minor) has low behavioural flexibility in its response to approaching humans
- Creator:
- Mikula, Peter, Kwieciński, Zbigniew, Kaługa, Ireneusz, and Tryjanowski, Piotr
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- antipredator behaviour, charismatic species, escape distance, species conservation, and urbanisation
- Language:
- English
- Description:
- The ongoing growth of the human population will increase the rate of wildlife-human interactions. High levels of animal tolerance and flexible responses towards human presence seem to be among the key mechanisms behind successful wildlife-human coexistence, but this behaviour remains unexplored for most populations and species of animals. Here, we investigate the escape behaviour (measured as flight initiation distance) of the Crimean population of a charismatic and declining bird species, the lesser grey shrike (Lanius minor). We examined its relationship with starting distance of the approaching human, directness of that approach (direct or tangential), habitat type (rural or suburban), and height of the perch used by shrikes. We found that the starting distance was significantly associated with escape responses of shrikes to approaching humans. In contrast, we found no significant association between escape responses and directness of approach, habitat type, or height of perch. Our results indicate that the lesser grey shrike may exhibit low flexibility in their escape responses towards humans which may have implications for their conservation management. Our results also indicate that the widely used 30 m threshold for minimum starting distance may be insufficient for rural populations, even of small passerines.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
38. The First United Workshop on Microsporidia from Invertebrate and Vertebrate Hosts
- Creator:
- Weiss, Louis M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Microsporidia, taxonomy, phylogeny, meetings, differentiation, genome, insect pathogens, fish pathogens, and microsporidiosis
- Language:
- English
- Description:
- The phylum Microsporidia is a large group of parasitic unicellular eukaryotes that infect a wide range of invertebrate and vertebrate taxa. These organisms are significant human and veterinary pathogens with impacts on medicine, agriculture and aquaculture. Scientists working on these pathogens represent diverse disciplines that have had limited opportunities for detailed interactions. A NATO Advanced Research Workshop 'Emergent Pathogens in the 21st Century: First United Workshop on Microsporidia from Invertebrate and Vertebrate Hosts' was held July 12-15, 2004 at the Institute of Parasitology of the Academy of Sciences of the Czech Republic to bring together experts in insect, fish, veterinary and human microsporidiosis for the exchange of information on these pathogens. At this meeting, discussions were held on issues related to taxonomy and phylogeny. It was recognized that microsporidia are related to fungi, but the strong opinion of the participants was that the International Code of Zoological Nomenclature should continue to be applied for taxonomic descriptions of the Microsporidia and that they be treated as an independent group emerging from a paraphyletic fungi. There continues to be exponential growth in the pace and volume of research on these ubiquitous intracellular protists. The small genomes of these organisms and the reduction in the size of many of their genes are of interest to many disciplines. Many microsporidia are dimorphic and the mechanisms underlying these morphologic changes remain to be elucidated. Epidemiologic studies to clarify the source of human microsporidiosis and ecologic studies to understand the multifaceted relationship of the Microsporidia and their hosts are important avenues of investigation. Studies on the Microsporidia should prove useful to many fields of biologic investigation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
39. The occurrence of metacercariae of Petasiger (Digenea: Echinostomatidae) in an unusual site, within the lateral line scales of cyprinid fishes
- Creator:
- Kálmán Molnár, Gibson, David I, Cech, Gábor, Papp, Melitta, Deák-Paulus, Petra, Juhász, Lajos, Tóth, Norbert, and Székely, Csaba
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- kaprovití, Cyprinidae, Balaton (Maďarsko : jezero), Balaton Lake (Hungary), metacercaria, molecular identification, Kis-Balaton Reservoir, 2, and 59
- Language:
- English
- Description:
- During a regular veterinary inspection of fishes from Lake Balaton, Hungary, echinostomatid metacercariae (Digenea), with collar spines characteristic of species of the genera Petasiger Dietz, 1909 and Paryphostomum Dietz, 1909, were found in the lateral line scales of a roach Rutilus rutilus (Linnaeus), an apparently unique site. In a subsequent examination of 586 fishes from 20 different species, similar infections were found in 11 species. The infection was virtually restricted to the lateral line scales, other scales being infected only incidentally. These encysted metacercariae had 27 collar spines, including eight larger angle spines and 19 smaller dorsal spines arranged in two rows. Two types of metacercarial cyst were found. One type had a cyst diameter of 138-171 µm × 105-120 µm and three central dorsal spines that were larger than the remainder and tended to resemble the angle spines. The second type of metacercarial cyst had a diameter of 128-157 µm × 105-115 µm and all 19 dorsal spines of the metacercaria were of a similar size. ITS sequences of the second type of metacercaria exhibited a 100% similarity to sequences of two adult Petasiger phalacrocoracis (Yamaguti, 1939) specimens collected from the gut of Phalacrocorax carbo (Linnaeus) in Hungary and to P. phalacrocoracis deposited in the GenBank database. Sequences obtained from two metacercariae of the first type showed a 2.8-2.9 % difference from sequences of the second type of metacercaria and from those of adult specimens of P. phalacrocoracis from cormorants. Based on these results, the second type metacercaria is considered to be a larval stage of P. phalacrocoracis, but the identity of the first type is uncertain. The unusual location of these metacercariae in the lateral line scales is discussed in relation to their transmission., Kálmán Molnár, David I. Gibson, Gábor Cech, Melitta Papp, Petra Deák-Paulus, Lajos Juhász, Norbert Tóth, Csaba Székely., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
40. The PsbH protein of photosystem 2
- Creator:
- Komenda, J., Štys, D., and Lupínková, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chloroplast, cyanobacterium, D1 protein, phosphorylation, and photosynthesis
- Language:
- Multiple languages
- Description:
- The PsbH protein belongs to a group of small protein subunits of the photosystem 2 (PS2) complex and genes encoding PsbH homologues have been so far found in all studied oxygenic phototrophs. This single helix membrane protein is important for the proper function of the PS2 acceptor side and for stable assembly of PS2. Its hypothetical function as an analogue of the H subunit of the bacterial reaction centre as well as a putative role of its phosphorylation is evaluated. and J. Komenda, D. Štys, L. Lupínková.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public