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The aim of the study was to determine the existence and co-existence patterns of VIP and NPY in neurons and nerve fibers of porcine lumbar-sacral sympathetic chain ganglia. The studied ganglia were fixed with 4% buffered paraformaldehyde (perfusion) and then labeled by means of double-immunofluorescence using a mixture of antibodies cultivated in different species. The highest number of NPY-positive cells was observed in the lumbar ganglia and diminished in the direction of the caudal, where only single neurons were observed. In contrast, a different pattern of distribution was observed for VIP-positive neurons, whose number was higher in the more caudally located ganglia. Two populations of VIP-positive neurons could be distinguished: single, showing strong immunofluorescence and often with visible processes, located in the central part of the ganglia and a second population, composed of clusters of 4-8 cells and often co-localizing NPY. VIP-positive nerve fibers surrounded both NPY+ neurons and neurons lacking either NPY and/or VIP. The presence of a small number of NPY-positive neurons exhibiting very weak immunofluorescence in more caudally located SChG could suggest a "switch" of neuromediators produced there. An increase in the percentage of non-noradrenergic sympathetic neurons in more caudally located SChG may thus be implicative for a specific innervation pattern of target tissues of these ganglia.
Repeating outbreaks of the Scots pine pests, effecting in stands damages, are the most important problems of forest protection. In extreme cases they pose a real threat to the stability of stands. Naturally occurring entomopathogenic nematodes are important regulatory factors in insect populations. Many species are employed as biological agents to control the insect pests. The objectives of this research was to describe the influence of potential forest pests on occurrence and abundance of entomopathogenic nematodes. Entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) were studied in woodland soils in northern Poland. Soil samples were collected from 2010 to 2015 from coniferous forests with abundant suitable insect hosts: the beetle grubs of Melolontha melolontha L. living in the soil (Coleoptera: Scarabaeidae) and foliage feeders Diprionidae spp. (Hymenoptera) and the caterpillar of Dendrolimus pini L., Panolis flammea Den. et Schiff. and Bupalus piniarius L. butterflies. Nematodes occurred in all type of forest and 171 soil samples were taken from 40 localities. Each study plot was approximately 100 m² and 20 cm deep; 50 individual samples were taken using Egner’s stick, making the bulk sample approximately 600 cm 3 in volume. The presence of entomopathogenic nematodes in the soil samples were determined using a standard Galleria mellonella baiting technique. Entomopathogenic nematodes were isolated from 52 soil samples (30,4%). Three species of the genus Steinernema (Steinernema feltiae, S. affine, S. silvaticum) and anyone of the genus Heterorhabditis were recorded. S. feltiae was the most common species and distinguished by the largest ecological flexibility especially to hosts. The largest number of S. feltiae samples was isolated in the places of butterfly outbreak P. flammea and also in the places of mass occurrence of beetle grubs of M. melolontha. In the feeding places of beetle of Scarabaeidae a high share of S. affine was noted too. The more rarely noted was S. silvaticum especially in outbreak of Diprionidae spp. The most abundance of entomopathogenic nematodes community was 140 000 ind./m² in sites with M. melolontha grubs.
The authors showed the frequency of occurrence of trichomonadosis and candidosis in 31 842 women living in the Upper Silesia territory. The most extensive invasion of T. vaginalis and C. albicans was found in autumn, and in women 24-34 years old.
The diversity and sustainability of species composition are important topic of forest research. The possibility to observe the coexistence of tree species in a given forest patch and their succession in the next generation is limited because there are few forests unaffected by management activities. For this reason, the study was conducted in the oldest part of the Białowieża National Park, called Strict Reserve. The purpose of the research was to determine the relationship between the quantity of individual tree species in the overstorey (the standing volume of trees with the diameter at breast height d≥8 cm) and regeneration layer (the total height of trees with the diameter at breast height d<8 cm or height h≤1.3 m) as well as the relationships between those stand layers. Multiple regression and canonical analysis were used to determine the relationships between 12 tree species (tab. 1). The research material was the results of measurements of 920 concentric sample plots conducted in 1995 and 2005. In the overstorey, the correlation coefficient between the standing volume of a given tree species on sample plots and the standing volume of other tree species assumed for each species both significant positive values (species ‘co−occurrence’), significant negative values (species ‘avoidance’) and close to zero values (fig. 1). The same was true for the regeneration layer (fig. 2). In eight cases the correlation between the total height of trees of a given species in the regeneration layer and the standing volume of trees from the overstorey showed the highest positive values when referred to the ‘regeneration−overstorey’ relationship of the same species (fig. 3). The same referred to the ‘overstorey−regeneration’ relationship (fig. 4). Eight of the canonical variables turned out to be significant (tab. 2). For the first canonical variable, standing volume of hornbeam in the overstorey (Gb_m) showed the highest absolute value of the loading factor in the first dataset, while the variable the total height of hornbeam trees in the regeneration layer (Gb_o) – in the other dataset (fig. 5). The total redundancy was 20.7%, which means that such part of the variance of the total height of individual tree species in the regeneration layer could be explained by their standing volume in the overstorey. The sequence of tree generations understood as the relationship between species composition of the regeneration and overstorey layers was associated with life strategies of tree species.
The maintenance of Borrelia burgdorferi s.1. in the environment is dependent on the zoonotic cycle involving tick vectors and certain reservoir hosts. It is well known, that the same species of wild rodents, as well as the vector Ixodes ricinus, are often co-infected with at least two genomospecies of B. burgdorferi s.1.: B. afzelii and B. garinii. The ticks collected from two rodent species: Clethrionomys glareolus and Apodemus flavicollis were examined for the presence of B. burgdorferi s.1., as well as for B. garinii and B. afzelii. In this study, an immunofluorescent antibody assay (lFA) and polymerase chain reaction (PCR) protocols were used. The high level of infestation in rodents (90% for C. glareolus and nearly 100% for A. flavicollis) shows that wild rodents are important hosts of the immature stages of I. ricinus. A high percent of Borrelia positive ticks collected from bank voles and yellow necked mice; above 7% determined by 1FA and 2% determined by PCR, elearly revealed that these species of animals are competent zoonotic reservoirs of B. burgdorferi s.l.
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