Venturia inaequalis-inhibiting Diels-Alder adducts from Morus root bark

In organic apple orcharding there is a continuous need for natural fungicides effective against Venturia inaequalis (Cooke) Winter, the causal agent of apple scab. In this study an in vitro assay is presented for determining the germination inhibitory potential of extracts and pure compounds. From a screening of plant extracts, the methanol extract of Morus root bark revealed distinct V. inaequalis inhibiting qualities, which were subjected to a bioguided fractionation. Among the isolated metabolites [moracins M (1), O/P (2), kuwanon L (3), and sanggenons D (4), B (5), G (6), O (7), E (8), and C (9)] all the Diels-Alder adducts (3-9) showed an antifungal activity with IC50 values between 10 and 123 microM. The in vitro activity of the most active fraction (A5, IC50 39.0 +/- 4.2 microg/mL) was evaluated in vivo, confirming a distinct antifungal activity against V. inaequalis for the tested natural material.     

Long-range-projecting GABAergic neurons modulate inhibition in hippocampus and entorhinal cortex

The hippocampus and entorhinal cortex play a pivotal role in spatial learning and memory. The two forebrain regions are highly interconnected via excitatory pathways. Using optogenetic tools, we identified and characterized long-range γ-aminobutyric acid-releasing (GABAergic) neurons that provide a bidirectional hippocampal-entorhinal inhibitory connectivity and preferentially target GABAergic interneurons. Activation of long-range GABAergic axons enhances sub- and suprathreshold rhythmic theta activity of postsynaptic neurons in the target areas.     

Plasmid DNA immunization with Trypanosoma cruzi genes induces cardiac and clinical protection against Chagas disease in the canine model

The only existing preventive measure against American trypanosomosis, or Chagas disease, is the control of the transmitting insect, which has only been effective in a few South American regions. Currently, there is no vaccine available to prevent this disease. Here, we present the clinical and cardiac levels of protection induced by expression to Trypanosoma cruzi genes encoding the TcSP and TcSSP4 proteins in the canine model. Physical examination, diagnostic chagasic serology, and serial electrocardiograms were performed before and after immunization, as well as after experimental infection. We found that immunization with recombinant plasmids prevented hyperthermia in the acute phase of experimental infection and produced lymphadenomegaly as an immunological response against the parasite and additionally prevented heart rate elevation (tachycardia) in the acute and/or chronic stages of infection. Immunization with T. cruzi genes encoding the TcSP and TcSSP4 antigens diminished the quality and quantity of the electrocardiographic abnormalities, thereby avoiding progression to more severe developments such as right bundle branch block or ventricular premature complexes in a greater number of dogs.     

Kinetics of single and dual infection of calves with an Asian atypical bovine pestivirus and a highly virulent strain of bovine viral diarrhoea virus 1

Atypical bovine pestiviruses related to bovine viral diarrhoea virus (BVDV) have recently been detected in cattle from South America, Asia and Europe. The purpose of this study was to compare the clinical and virological aspects of dual infection with BVDV-1 (Horton 916) and an Asian atypical bovine pestivirus (Th/04_KhonKaen) in na?ve calves, in comparison to single infections. Milder clinical signs were observed in the animals infected with single Th/04_KhonKaen strain. Leukocytopenia and lymphocytopenia were observed in all infected groups at a similar level which correlated with the onset of viraemia. Co-infection with both viruses led to prolonged fever in comparison to single strain inoculated groups and simultaneous replication of concurrent viruses in blood and in the upper respiratory tract. Following the infections all the calves seroconverted against homologous strains. Atypical pestiviruses pose a serious threat to livestock health and BVDV eradication, since they may have the potential to be widely spread in cattle populations without being detected and differentiated from other BVDV infections.     

Ixodes eldaricus Djaparidze, 1950 (Ixodidae) on migrating birds--reported first time in Poland

During the ornithological "Operation Baltic" on the Hel Peninsula (the Baltic Sea coast in Poland) the first case of transfer to Poland of ticks of the species Ixodes eldaricus Djaparidze, 1950, on Prunella modularis (one female tick) and Erithacus rubecula (two males and one female tick). P. modularis and E. rubecula have not previously been recorded among the hosts of this tick species. Although the natural populations of I. eldaricus are very distant from Poland, it should be taken into account that this and other species of ticks may be transferred every year on migratory birds in the southern part of Central Europe and further north. Each case requires faunistic observation and epidemiological and morphological studies to exclude diagnostic confusion between very similar morphology in specimens of the genus Ixodes.     

Impact of individual training parameters and manner of taking breath odor samples on the reliability of canines as cancer screeners

The aim of this study was to assess the progress in operant conditioning of dogs during 3 training phases up to a level where the dogs performed a minimum of 40 correct indications without false alerts and hesitations in at least 100 trials in each phase, and to compare the training results with the working phase. Breath samples from 57, 45, and 118 patients with breast cancer, melanoma, and lung cancer, respectively, were used as patterns, with samples from 305 healthy volunteers as controls. Six dogs in 2 age-groups (20 months vs. 6 months old) were used for the training. In phase I, the dogs were trained to indicate by sitting or lying down before the breath samples taken from cancer patients (pattern odor) coupled with food odor and placed among 4 blank samples (a lineup of 5 samples). In phase II, a pattern sample without food odor was placed among blank samples. In phase III as well as in the working phase, a pattern sample was placed among control samples. Significant individual differences were found in dogs’ performance during the training. The percentage of trials with prompts to achieve self-dependent work decreased in older dogs in consecutive training phases, but increased in phase II in the younger dogs. The increasing level of challenge in consecutive training phases resulted in a higher percentage of false alerts and misses, and in younger dogs, decreased motivation for sniffing the odor samples was observed in training phase III. Nonsignificant and negative correlations between the training phases and working phase in the percentage of correct indications and false alerts show that it is difficult to predict the performance of fully trained dogs on the basis of the results achieved during the training. Fully trained dogs discriminated pattern breath samples (cancer) from healthy controls with 79% sensitivity and 78% specificity, or with 50% sensitivity at the probability of correct response by chance of 50% and 20%, respectively. The sensitivity decreased to 68% and 37%, respectively, when each sample was tested only once, although being better than by chance (P < 0.05). The percentage of false alerts and misses is difficult to reduce during the training; thus, the percentage of correct indications tended to decrease in the course of training phases II and III. Odor samples taken in hospitals may contain components of “hospital odors,” which may be a confounding factor for dogs’ indications. Using trained dogs for cancer screening on the basis of detection of odor markers still requires further study.     

Detection of runs of homozygosity in conserved and commercial pig breeds in Poland

Runs of homozygosity (ROH) are continuous segments of the genome that arose as a result of inbreeding, resulting in the inheritance of identical haplotypes from both parents who shared a common ancestor. In the present study, we performed a detailed characterization and comparison of ROH in four pig breeds, including intensively selected Polish Landrace as well as native unselected animals of Puławska and two Złotnicka breeds (White and Spotted). We used a medium-density PorcineSNP60 BeadChip assay (Illumina) and cgaTOH software to detect ROH covering a minimum of 30 adjacent SNPs and maintaining a size over 1 Mb. By analysing ROH distribution and frequency across the genome, we also identified genomic regions with high ROH frequency (so-called “ROH hotspots”). The obtained results showed that the analysed conserved breeds were characterized by a higher ROH span and higher ROH-based inbreeding coefficients (F_ROH), which likely result from past population bottlenecks, increasing the overall inbreeding level within these populations. The analysis of ROH distribution across the genomes revealed the presence of both shared and breed-specific ROH hotspots. These hotspots, presumably representing genome regions under selection, overlapped with a variety of genes associated with processes connected with immune system functioning, reproduction, glucose homeostasis and metabolism. The genome regions with ROH hotspots overlapping in all analysed populations, located on SSC4 (51.9–55.9 Mb) and 13 (92.6–97.8 Mb), covered thirty-one different genes, including MMP16, SLC7A13, ATP6V0D2, CNGB3, WWiP1, RiMDN1 and CPNE3. These genes are primarily associated with biological regulation and metabolism, processes that could be responsible for the variety of the selected production and functional features.     

Ant-induced soil modification and its effect on plant below-ground biomass

Lasius flavus is a dominant mound-building ant species of temperate grasslands that significantly modifies soil parameters. These modifications are usually the result of workers’ activities such as food accumulation and nest construction. An alternative hypothesis that could explain changes in soil is colony founding in areas of higher soil fertility.In our study we investigated several soil parameters sampled in 10 ant nests and adjacent (control) plots in mountain grassland in Slovakia. The alternative hypothesis was tested by comparing occupied and abandoned mounds. While we found increased concentrations of available P and K in the nests, concentrations of total C, total N, Ca²⁺ and Mg²⁺ were lower there. We propose that differences found between the soil of nests and control plots are entirely a product of ant activity during mound occupancy and not due to initial soil differences during nest establishment. This was confirmed by the comparison of occupied and abandoned nests in which the soil fertility of abandoned nests was similar to conditions in the surrounding soil.Along with the modification of soil chemistry, we recorded changes in soil physical properties and the vertical distribution of nutrients. Ant nests were characterized by the dominance of 0.02–0.1 mm particles and lower bulk density. In the same habitat, nutrient concentrations did not change along the vertical gradient in contrast to control plots where soil nutrients decreased and bulk density increased with depth. Root biomass followed the vertical pattern observed with nutrients: in control plots, most roots were concentrated in the uppermost layer (0–3 cm), whereas they were evenly distributed along the vertical gradient in the nests. We also found that rhizome internodes of Agrostis capillaris were thinner and longer in plants from the mounds. Changes in soil physical properties, vertical distribution of nutrients and root biomass in the nests are most probably a consequence of mounding and soil mixing (bioturbation), which has been less reported on in ant-soil studies.     

Cover cropping influences physico-chemical soil properties under direct drilling soybean

In seeking effective methods to prevent soil degradation, conservation tillage plays an important protective role. Apart from significantly reducing production costs, cover crops contributes to beneficial changes in the soil environment. A three-year field experiment included three cover crops (winter rye, winter oilseed rape, and white mustard) subjected to mulching or desiccation and to the action of a herbicide at three rates (100%, 75%, and 50%). The study evaluated soil moisture and the content of organic matter, phosphorus, potassium, and magnesium in two soil layers (0–15?cm and 15–30?cm). Cover cropping had a positive effect on soil organic matter content. More organic matter (by 4.7%) was recorded in the topsoil layer (0–15?cm). Among the cover crops most favorable effect on the content of organic matter in the soil had white mustard (an increase of 14.2%) compared to the control. Moreover, rye and white mustard mulch increased the soil content of phosphorus and magnesium, while oilseed rape mulch increased the potassium content. At the critical growth stages (the flowering/pod set) of soybean (Glycine max (L.) Merril), soil moisture was dependent on mulching treatment and soil layers.