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Detection of Sarcocystis parasites in environmental samples from Lithuanian farms /
No full textMost studies on apicomplexan Sarcocystis spp. in domestic animals have primarily focused on examining animal carcasses using both morphological and molecular methods. However, to accurately assess the risk of Sarcocystis infections in livestock and to develop effective prevention strategies, it is essential to investigate the environmental reservoirs of these parasites. The aim of this study was to identify Sarcocystis species with domestic animals as intermediate hosts by analysing environmental samples (water, hay, and soil) collected from Lithuanian farms and to compare their occurrence across different sample types. In total, 90 environmental samples were collected over 3 years and analysed for the presence of Sarcocystis spp. using nested polymerase chain reactions targeting the cox1 gene. The results indicated that livestock are most likely to acquire infections via the ingestion of contaminated water or feed, while soil posed a lower risk of transmission. An assessment of species distribution across sampled farms revealed that the type of livestock raised did not influence the diversity of Sarcocystis spp. Notably, at least six of seven target species (S. arieticanis, S. bertrami, S. bovifelis, S. capracanis, S. cruzi, S. miescheriana, S. tenella) were detected at least once on eight of 10 farms. Additionally, two zoonotic Sarcocystis species, S. hominis and S. suihominis, were identified in environmental samples. This study emphasises the potential risk of livestock infection through contaminated environmental and feed sources and highlights the critical role of environmental monitoring in preventing the transmission of Sarcocystis spp. to farm animals
Changes in carbon isotope distribution in sediments of Lake Plateliai, Lithuania, over the last 130 years /
No full textThe radiocarbon (14C) dating of lake sediments is widely used to estimate the so-called reservoir age (RA), i.e. the 14C age difference between the atmospheric and lake ecosystem carbon reservoirs. However, lake sediments are a mixture of autochthonous and various allochthonous carbon sources having distinct 14C specific activities. The RA depends on the catchment bedrock, CO2 exchange rates between water and the atmosphere, which are affected by organic carbon production and decomposition rates, inflow/outflow of organic and inorganic mater, water residence time, water level fluctuations, climate change, and other environmental factors impacting the lake’s catchment area. Every disturbance affecting carbon exchange between the water ecosystem, the terrestrial environment, and the atmosphere impacts carbon isotope distribution in the lake ecosystem.Lake Plateliai is the largest lake in the north-western part of Lithuania (Samogitia). It is located on the territory of Samogitia National Park. The absence of cultivated fields on the park’s territory conditioned the lake to remain one of the cleanest in Lithuania. The present study focusses on sediment records from Lake Plateliai over the last 130 years. This time period is related to dam-induced lake’s water level fluctuations, increase/decrease in primary productivity due to intensive agricultural development since the 1960s, and its decline in the 1990s.The aim of this work was to estimate how environmental factors have influenced the carbon cycle within the lake and how these impacts are recorded in sediments, i.e., changes in sedimentation rate, carbon isotope distribution among organic sediment fractions.During the last 130 years, the radiocarbon reservoir age of the of the alkali soluble and alkali insoluble fractions of lake sediments has been reduced by 872.4 ±80 years, and a decreasing trend of 14C concentration values is recorded/observed in the upper layers. The14C specific activity values in both sediment organic fractions coincided during the last ten years and 1885-1932. However, changes in the water level during the period 1963-1976 and unknown events in 1939-1940 led to the introduction of allochthonous origin matter into the lake ecosystem, resulting lower 14C concentrations in the alkali soluble fraction compared to the alkali insoluble fraction
Haemoproteus tartakovskyi and Plasmodium relictum (Haemosporida, Apicomplexa) differentially express distinct 18S rRNA gene variants in bird hosts and dipteran vectors /
No full textMost mammalian Plasmodium species possess distinct 18S ribosomal RNA (rRNA) gene copies, which are differentially expressed in vertebrate hosts and mosquito vectors. Although similar sequence patterns were found in avian haemosporidian parasites, expression patterns have not been studied yet. This study aimed to test whether 18S variants of Plasmodium relictum SGS1 and Haemoproteus tartakovskyi SISKIN1 are expressed differentially in bird hosts and dipteran vectors using real-time quantitative polymerase chain reaction (qPCR) and chromogenic in situ hybridization (CISH)
Leucocytozoon infections in tits (Aves, Paridae): blood and tissue stages investigated using an integrative approach /
No full textLeucocytozoon species are cosmopolitan and prevalent avian parasites, with some infections being lethal, mainly due to the exo-erythrocytic development of the parasite in bird tissues. The patterns of exo-erythrocytic development in Leucocytozoon spp. infections in wild birds remain poorly studied. This study investigated the development of Leucocytozoon spp. tissue stages in tits (Paridae). Great tits (Parus major), Blue tits (Cyanistes caeruleus), and Coal tits (Periparus ater) were screened for infections using an integrative approach that consisted of microscopic analysis of thin blood smears, histological techniques, chromogenic in situ hybridization (CISH), PCR-based methods, and phylogenetic analysis. In total, 41 individuals were analyzed (eight naturally infected that were selected and euthanized, and 33 found dead in the wild and opportunistically sampled). Among the naturally infected birds, all individuals that were microscopically positive for Leucocytozoon species were also PCR-positive for these parasites. Co-infections with Plasmodium spp. and Haemoproteus spp. were commonly found, mainly among the opportunistically sampled birds. Two morphotypes were identified, Leucocytozoon majoris (Laveran, 1902) and Leucocytozoon fringillinarum Woodcock, 1910. Tissue stages were present in three birds sampled exclusively during the non-breeding season, two of them with meronts developing in the kidneys and liver, and one individual with a megalomeront in the heart. All the exo-erythrocytic stages were confirmed to be Leucocytozoon spp. by CISH using a Leucocytozoon genus-specific probe. Phylogenetic analysis placed parasite lineages with different morphotypes in separate clades. The developmental patterns of exo-erythrocytic stages of Leucocytozoon spp. in naturally infected passerines are poorly understood, requiring further research
The phenology of Epilobium hirsutum L.: assessing marker compounds variability of a pharmaceutically important plant remedy /
No full textBackground: Epilobium hirsutum L. (Onagraceae), a perennial medicinal plant, has considerable pharmaceutical value due to its phenolic acids, flavonoids, and ellagitannins, including oenothein A and B. The plant is reported to have therapeutic benefits for several conditions, such as prostate gland, bladder, and hormonal disorders. This study aimed to provide evidence-based data on the chemical composition of the species over a 1-year cycle and define the optimal harvesting period, which is essential to ensure consistency and efficacy in plant-derived products. Methods: The phytochemical variability of E. hirsutum across habitats (mesic grassland, wet grassland, and lake shore), plant parts (leaves and stems), and phenological stages (from April to October) was investigated. Using HPLC and HPTLC methods, 11 pharmacologically active marker compounds were quantified in 78 samples collected every 2 weeks during 2023. Results: Among the hydroxycinnamic acids, chlorogenic acid was dominant in samples from shaded habitats, with maximum accumulation in samples from leaves during the vegetative phase (up to 2.25 mg/g DW). Flavonoids such as isoquercitrin and hyperoside peaked in leaves from the lake shore and wet grassland habitats during flowering. Oenothein B, a major ellagitannin, showed the highest concentrations in wet grassland leaves during flowering (73.97 mg/g DW). Conclusion: This study is the first to integrate habitat, phenology, and plant part data to characterise seasonal dynamics of key marker compounds in E. hirsutum under natural east-part of the United Kingdom conditions. Shaded, moist habitats were found to promote higher biosynthesis of secondary metabolites, whereas open, dry conditions favoured biomass yield. Distinct seasonal patterns in the accumulation of β-hydroxycinnamic acids and ellagitannins provide insight into their physiological functions and potential pharmacological significance. By identifying the dynamics of marker compounds and optimal harvesting periods, the study provides a framework for sustainable industrial practices for pharmaceutical raw material production and supports standardisation in herbal production
A literature review on the role of Culicoides in the transmission of avian blood parasites in Europe /
No full textCulicoides (Diptera: Ceratopogonidae) biting midges are a diverse group of insect vectors that transmit pathogens affecting humans, livestock, and wild animals. Among them, Oropouche virus, African Horse sickness virus, and bluetongue virus are the most notable pathogens. However, comparatively little is known about which Culicoides species serve as vectors of wildlife parasites affecting wild birds globally, including the malaria-like parasite of the genus Haemoproteus (Haemosporida: Haemoproteidae) and kinetoplastid Trypanosoma (Trypanosomatida: Trypanosomatidae). Beyond the direct impact of their bites, infections by these parasites negatively affect wild birds from early developmental stages, significantly influencing their ecology and evolution. Here, we present a comprehensive review of the role of Culicoides species in the transmission of these two genera of avian parasites in Europe: Haemoproteus and Trypanosoma. We identify key information and methods used to study Culicoides–bird–parasite interactions, from insect sampling to vector competence assessment. Additionally, we highlight key knowledge gaps and propose future research directions in this area
How tropical biodiversity gets multiplied: Documentation of entomological proofs from the family Nepticulidae, tiny lepidopteran leaf miners ** /
No full textThe factors that generate the extraordinary biodiversity of tropical regions are likely multifaceted. In this study, we tested our working hypothesis that a mosaic of contrasting habitats plays a key role in shaping the diversity of tropical pygmy moths (Lepidoptera: Nepticulidae). To explore this, we selected four ecologically distinct localities in Honduras and investigated whether closely related but distinct Nepticulidae species occur in different habitats. Collected specimens were dissected, and their genital structures photographed and analyzed. Molecular divergence was assessed using DnaSP, with Maximum Likelihood phylogenetic trees constructed in MEGA. Bayesian phylogenetic analyses and mitotype networks construction (TCS algorithm) were also performed. Our findings are presented in two case studies. In Case Study 1, three closely related yet distinct species were discovered in separate localities; in Case Study 2, four other closely related species were found in environmentally different sites. Comparative material from Colombia and Peru was also examined. Based on integrated morphological and molecular analyses, eight new species were identified and formally described. We conclude that contrasting environmental conditions exert selective pressures, and that morphologically and genetically similar species—likely derived from a common ancestor—have diverged, exemplifying the process of adaptive radiation
Thermal maturity of the Silurian “hot” shales and correlation with the present geothermal variations in West Lithuania, Baltic Basin /
No full textThe most organic-rich shales are defined in the Dobele Fm. of the Aeronian Stage of about 10 m thick in west Lithuania. This particular layer is documented in the whole Baltic Basin. Compatible shales are widely distributed in other basins referred to as similar Silurian “hot” shales. The average TOC was estimated at 6.67 wt.% (good and excellent source rock). The thermal maturity of shales was evaluated through organic geochemical techniques, including TOC determination, Rock–Eval pyrolysis, and organic petrography studies. The thermal maturity varies from Tmax = 431 °C and eq.VRo = 0.65% (early oil) to Tmax = 468 °C and VRo = 1.38% (locally up to 1.94%) (late oil and wet to dry gas generation). It is notable, most of the study area is confined to regional-scale West Lithuanian Geothermal Anomaly. Most of the geothermal features, both palaeo- and recent, recorded in lateral variation in thermal maturity of shales unravel persistence of heat flow. Locally, the Variscan tectonic activity was imprinted in thermal maturity of organic matter-rich shales (Žemaičių Naumiestis anomaly)
Oomycete diversity and ecology in declining alder stands in Switzerland /
No full textIn this study, we assessed the occurrence and diversity of four oomycete genera ( Phytophthora , Phytopythium , Pythium , and Globisporangium ) in 13 declining alder ( Alnus glutinosa and A. incana ) stands in Switzerland. For this, we sampled and analyzed soil from tree rhizosphere, water from streams and rivers along which the stands were located, and symptomatic alder bark. The overall isolation rate was 47.2%, with a total of 400 oomycete isolates recovered at all 13 sites. The highest incidence of oomycete isolates was in soil samples (baiting, 82.5% isolation rate), followed by water (baiting, 14.7%), and bark (direct isolation, 2.7%). Of all recovered oomycete isolates, 90.3% could be successfully assigned to a known species, for a total of 23 species identified, including both preferential saprotrophs and pathogens. Among all genera, Phytophthora was the most abundant with 273 isolates (75.6%), followed by Phytopythium , Pythium , and Globisporangium . Oomycete species diversity showed a significant variation among substrates. Only one species— Phytophthora lacustris —was abundant in all substrates, while 16 species were restricted to a specific substrate, mainly soil. The rhizosphere of symptomatic alder trees harbored the most diverse oomycete community, highlighting once again the importance of soil as a reservoir for these microorganisms. Only two Phytophthora species were isolated from alder bark lesions, namely, P. × alni , the known causal agent of alder decline, and P. lacustris . The low recovery rate of P. × alni might be due to attempts to isolate it from old, inactive lesions, but may also suggest that alder decline might be caused by other oomycetes infecting the root system of the trees
Antimicrobial vitrimers synthesized from dipentaerythritol pentaacrylate and 2-hydroxy-3-phenoxypropyl acrylate for LCD 3D printing /
No full textIn this study, two monomers, dipentaerythritol pentaacrylate and 2-hydroxy-3-phenoxypropyl acrylate, were used to synthesize antimicrobial vitrimers with and without a transesterification catalyst and investigate their properties. The addition of the comonomer 2-hydroxy-3-phenoxypropyl acrylate to the photocurable resin reduced its viscosity and shrinkage but increased the gel point and reduced the brittleness and increased flexibility of the resulting polymers. All vitrimers exhibited self-welding and reprocessability properties and thermoresponsive shape memory, maintaining two permanent shapes. All vitrimers showed high antimicrobial activity against widely spread bacteria and fungal strains, including medically important ones. The resin, composed of dipentaerythritol pentaacrylate (1 mol) and 2-hydroxy-3-phenoxypropyl acrylate (10 mol), was applied to LCD 3D printing technology, and the Y-shaped connector was printed. In addition, the antimicrobial activity makes these vitrimers particularly important for use in areas with high microbial concentrations, such as medical facilities