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181.
Variation among Puccinia triticina isolates collected from triticale in Poland between 2012 and 2015 was studied based on virulence and simple sequence repeat (SSR) markers. Two hundred and forty-two single-uredinial isolates from four geographically separated locations were tested for virulence against 33 near-isogenic Thatcher lines containing known Lr resistance genes, and their molecular genotypes were characterized with 34 SSR markers. Structure and relationships of the regional and annual populations of P. triticina were analysed using an assignment-based approach for both the virulence and SSR data. The molecular marker analysis was based on two different models of SSR evolution: the stepwise mutation model with a variable mutation rate (SMMv) and the infinite alleles model (IAM). A highly significant deviation from Hardy–Weinberg equilibrium among SSR genotypes, a high proportion of heterozygotes, and a moderate association of relationships between virulence phenotypes and SSR genotypes were consistent with the occurrence of clonal lineages of related races within the population. While the results suggest that genetic drift and mutation affect variation within the pathogen population, it seems that migration has the most significant role in shaping the population structure of P. triticina occurring on triticale in Poland.  相似文献   
182.
Wounds on trees provide entrance for many members of the Ophiostomatales (Ascomycota), including economically damaging tree pathogens. Because very little is known regarding wound-associated fungi on hardwoods in Europe or their potential nitidulid beetle vectors (Coleoptera), the aim of this survey was to explore the diversity of these fungi in Poland. Wound samples associated with 26 tree species were collected from 18 stands in Poland. Fungi belonging to the Ophiostomatales were isolated and identified based on morphology and DNA sequence comparisons of five gene regions, combined with phylogenetic analyses. In total, 32 taxa were identified, including 20 known and 12 currently undescribed species. In addition, Grosmannia cainii, Ophiostoma cf. ponderosae, O. sparsiannulatum and Sporothrix aurorae were reported for the first time outside of the USA. The wound-associated members of the Ophiostomatales recovered from hardwoods showed high diversity and specificity. Among the species recovered, 16 belonged to Sporothrix, 11 represented Ophiostoma s. l., five could be assigned to Leptographium s. l., and one Graphilbum species was detected. Among the studied tree species, wounds on Quercus robur appeared to be the most vulnerable to infection by members of the Ophiostomatales. All the nitidulid beetle species were found in association with species assignable to Ophiostoma and Sporothrix. This study detected a significant association between the occurrence of species belonging to the Ophiostomatales and the health status of the wounded trees. Some of the isolated species were host specific although Ophiostoma quercus, the most frequently encountered species, had a broad host range.  相似文献   
183.
BackgroundThe endocannabinoid system (ECS) is composed of cannabinoid receptors type 1 (CBR1) and type 2 (CBR2), cannabinoid‐based ligands (endogenous chemically synthesized phytocannabinoids), and endogenous enzymes controlling their concentrations. Cannabinoid receptors (CBRs) have been identified in invertebrates and in almost all vertebrate species in the central and peripheral nervous system as well as in immune cells, where they control neuroimmune homeostasis. In humans, rodents, dogs, and cats, CBRs expression has been confirmed in the skin, and their expression and tissue distribution become disordered in pathological conditions. Cannabinoid receptors may be a possible therapeutic target in skin diseases.ObjectivesTo characterize the distribution and cellular expression of CBRs in the skin of horses under normal conditions.AnimalsFifteen healthy horses.MethodsUsing full‐thickness skin punch biopsy samples, skin‐derived primary epidermal keratinocytes and dermal‐derived cells, we performed analysis of Cnr1 and Cnr2 genes using real‐time PCR and CBR1 and CBR2 protein expression by confocal microscopy and Western blotting.ResultsNormal equine skin, including equine epidermal keratinocytes and dermal fibroblast‐like cells, all exhibited constant gene and protein expression of CBRs.Conclusions and Clinical ImportanceOur results represent a starting point for developing and translating new veterinary medicine‐based pharmacotherapies using ECS as a possible target.  相似文献   
184.
Zebrafish (Danio rerio) is a laboratory model organism used in different areas of biological research including studies of immune response and host–pathogen interactions. Thanks to many biological tools available, zebrafish becomes also an important model in aquaculture research since several fish viral infection models have been developed for zebrafish. Here, we have evaluated the possible use of zebrafish to study infections with fish viruses that have not yet been tested on this model organism. In vitro studies demonstrated that chum salmon reovirus (CSV; aquareovirus A) and two alloherpesviruses cyprinid herpesvirus 1 (CyHV‐1) and cyprinid herpesvirus 3 (CyHV‐3) are able to replicate in zebrafish cell lines ZF4 and SJD.1. Moreover, CSV induced a clear cytopathic effect and up‐regulated the expression of antiviral genes vig‐1 and mxa in both cell lines. In vivo studies demonstrated that both CSV and CyHV‐3 induce up‐regulation of vig‐1 and mxa expression in kidney and spleen of adult zebrafish after infection by i.p. injection but not in larvae after infection by immersion. CyHV‐3 is eliminated quickly from fish; therefore, virus clearing process could be evaluated, and in CSV‐infected fish, a prolonged confrontation of the host with the pathogen could be studied.  相似文献   
185.
The yield potential of 60 spring barley varieties was examined under controlled drought and natural conditions in the years 2011–2013. The studied varieties were genotyped with the 1536‐SNP barley oligonucleotide assay. In experiments with controlled drought conditions, the grain yield, 1,000‐grain weight, number of productive tillers and length of the main stem were measured. Physicochemical properties such as the specific surface area, water adsorption energy, fractal dimension and nanopore radius of the plant leaves were determined and correlated with yield‐forming traits. Field trials were conducted over 3 years at 14 locations, where along with the yield‐related traits, monthly rainfall and average temperature were monitored. Five varieties of high yield and five varieties relatively stable under both semi‐controlled and natural conditions were distinguished. The yield‐related traits observed in various locations were related to environmental variables relevant to water availability. The sum of the rainfall in April and May was negatively correlated with the 1,000‐grain weight and positively with the plant height. Positive relationships were found between plant height and temperatures in June and July. Five markers detected earlier as linked to the quantitative trait loci in the mapping populations were identified to have a coherent effect among varieties of various pedigree.  相似文献   
186.
Purpose

The objective of this study was to determine the long-term environmental changes induced by ancient landslide in the mountain fen. Attempts were made to demonstrate the progress of the soil cover restoration process about 200 years after the landslides and associated with changes in vegetation and soil microarthropod biodiversity and occurrence pattern associated with the restoration of soil cover.

Material and methods

The study covered mountain fen of the Caltho-Alnetum in the Babiogórski National Park in Outer Flysch Carpathians, Poland, where ancient landslide deposits are causing disturbance in fen hydrologic regime and over time related to various rate of fen area natural restoration processes. The drill test has been used to assess changes in layering and thickness of the fen soils. The following soil parameters, such as pH and total organic carbon content, were determined at each distinguish layer. The diversity and distribution pattern of soil microarthropods, represented by Collembola, was examined in two parts of the fen: restored and not-restored. The soil parameters, such as pH, electrical conductivity, total exchangeable base, total organic carbon, and nitrogen content, were determined in the soil samples simultaneously. The assessment of the vegetation structure recovery within studied mountain fen after landslide was referred to average parameters of the community completed for other natural mountain fens under the Caltho-Alnetum community. The research results were statistically verified.

Results and discussion

The test drillings showed that landslides change soil layering, site-specific soil properties of mountain fen such as chemistry (the statistically significant differences were noted only in the case of total organic carbon content), vegetation structure, and soil microarthropod communities. By changing site-specific conditions, landslides influence on the biodiversity and peatland ecosystems functioning.

Conclusion

Our results clearly demonstrate that the landslide itself initiated a complex and lengthy process of changes in biological aspects of peatlands including the biodiversity of the underground fauna and plant community. Soil microarthropod communities represented by Collembola can be used as a good indicator of mountain fen restoration process.

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187.
Climate change is expected to affect the flow regime, cause loss of habitat, change community composition and behavioural habits of fish. This study assessed the impact of climate change on ecologically relevant streamflow conditions for fish migration and spawning in the Vistula and the Odra river basins. Streamflow simulations obtained with the Soil and Water Assessment Tool (SWAT) for the historical period and two future horizons were driven by nine bias‐corrected EURO‐CORDEX Regional Climate Models under two greenhouse gas concentration trajectories. This study identified a subset of Indicators of Hydrological Alteration (IHA) that are relevant for pike, Esox lucius L., chub, Squalius cephalus (L.), and Atlantic salmon, Salmo salar L. IHA indicators were calculated and compared for different scenarios. An index‐based framework identified that all considered species will be impacted by climate change, with Atlantic salmon facing the largest impact. The model's uncertainty was addressed through an aggregation method that assessed inconsistencies in the model's response.  相似文献   
188.
Heavy metals in surface soils of the Warta river valley in an urban area In the urban area of the city of Poznan the contamination with heavy metals was investigated. From the top soil layers of five cross-sections of the valley of the Warta river 87 samples were collected. Beside common soil characteristics the contents of arsenic, barium, cadmium, chromium, copper, iron, lead, manganese, phosphorus and zinc were analyzed. Predominantly the level of contamination with heavy metals is low in the valley soils. A higher level was found in the area of the old city centre. Especially the contents of lead, copper and zinc were raised. Downstream of the sewage plant discharge into the river Warta increased contents of lead and cadmium were found. The distribution of heavy metals in the river Warta sediments indicates that the reason of the local increase of heavy metal contents is the sewage water discharge, Correlations between the content of different heavy metals and other soil properties (pH, clay and P-content, C/N-ratio) were calculated.  相似文献   
189.
190.

Background

The aim of the study was to demonstrate the immunohistochemical expression of proteins that affect the metastatic potential of a tumour, including matrix metalloproteinase 2 (MMP-2) and E-cadherin. Another objective was to determine their correlation with the expression of the Ki-67 antigen in metastasizing and non-metastasizing mammary carcinomas in female dogs. The study was conducted on 32 canine mammary carcinomas (12 metastatic and 20 non-metastatic), classified as simple tubular and tubulopapillary carcinomas. Immunohistochemistry was performed to evaluate the expression of MMP-2, E-cadherin and Ki-67 antigen.

Results

MMP-2 was expressed in 85 % of the non-metastatic tumours and in all the metastatic tumours, while E-cadherin was expressed in 85 % of the non-metastatic tumours and in 66 % of the metastatic tumours. The Ki-67 antigen was expressed in 65 % of the non-metastatic tumours and in 91 % of the metastatic tumours. The mean Ki-67 expression was slightly higher in tumours that had metastasized (1.5?±?0.90 vs 1.1?±?0.94; p?=?0.22). A similar relationship was found in terms of the intensity of the MMP-2 expression (2.9?±?1.9 vs 2.7?±?2.4; p?=?0.50). A decrease in the expression of E-cadherin (2.8?±?2.5) was found in metastatic tumours compared to the expression in non-metastatic tumours (3.2?±?2.3). However, these differences were not statistically significant (p?=?0.63).

Conclusion

We did not show significant differences in MMP-2, E-cadherin and Ki-67 expression between metastatic and non-metastatic tumours due to low number of cases studied, however further experiments are necessary to assess the role of these antigens in the process of canine mammary tumours metastasis.
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