Preliminary molecular identification of drug resistant cyathostomes in Italy

Veterinary Research Communications -     

Differential impact of chronic ozone exposure on expanding and fully expanded poplar leaves

Populus tremula L. × Populus alba L. (Populus ×c anescens (Aiton) Smith) - clone INRA 717-1-B4 saplings (50 cm apex to base and carrying 19 leaves on average) - were followed for 28 days. Half of the trees were grown in charcoal-filtered air while the other half were exposed to 120 ppb ozone for 11 h a day during the light period. The expanding leaf number 4 was tagged at the beginning of the experiment and finished expansion between 7 and 14 days. These leaves were harvested weekly for biochemical and proteome analyses using quantitative bidimensional electrophoresis (DiGE). Independent of the ozone treatment, all the analyses allowed a distinction between expanding and adult leaves. The results indicate that during the expansion phase (Days 0-7) the enzymatic machinery of the leaves is set up, and remains dynamically stable in the adult leaves (Days 14-28). Although ozone had no apparent effect on expanding leaves, the metabolic stability in fully expanded leaves observed in ozone-free plants was disturbed after 2 weeks of exposure and a stress-induced response became apparent.     

Sex chromosomes and quantitative sex expression in monoecious hemp (Cannabis sativa L.)

Hemp (Cannabis sativa) has a highly variable sexual phenotype. In dioecious hemp, the sex is controlled by heteromorphic sex chromosomes according to an X-to-autosomes equilibrium. However, in monoecious hemp, the sex determinism remains widely unknown and has never been related to a quantitative approach of sex expression. The present paper aims to contribute to the comprehension of the sex determinism in monoecious hemp by assessing the genotypic variability of its sex expression and establishing its sex chromosomes. Five monoecious and one dioecious cultivars were grown in controlled conditions under several photoperiods. The monoecy degree of 194 monoecious plants was recorded at each node by a figure ranging from 0 (male flowers only) to 6 (female flowers only). The genome size of 55 plants was determined by flow cytometry. The DNA of 115 monoecious plants was screened with the male-associated marker MADC2. The monoecy degree varied significantly among monoecious cultivars from 3.36 ± 2.28 in ‘Uso 31’ to 5.70 ± 0.81 in the most feminised ‘Epsilon 68’. The variation of monoecy degree among cultivars remained consistent across trials despite a significant “cultivar × trial” interaction and partly agreed with their earliness. The genome size of monoecious plants (1.791 ± 0.017 pg) was not different from that of females (1.789 ± 0.019 pg) but significantly lower than that of males (1.835 ± 0.019 pg). MADC2 was absent from all monoecious plants. These results strongly support that cultivars of monoecious hemp have the XX constitution and that their sex expression has a genetic basis.     

Metabolic diversity in apple germplasm

We analysed metabolic diversity in apples from wild species, elite material and a F₁ population, using liquid chromatography–mass spectrometry (LC‐QTOF‐MS). The evaluated elite material appeared to have strongly reduced levels of phenolic compounds, down to 1% of the concentrations in the investigated wild germplasm. In one quarter of the F₁ population, the concentrations of phenolic compounds such as quercetin derivatives, procyanidin, catechin and epicatechin were further significantly reduced, due to accumulation of recessive alleles of putatively leucoanthocyanidin reductase, a structural gene that is located at the top of LG16. In another part of F₁ progeny, putatively glycosylated forms of β‐glycols were up to 50 times more abundant compared to both parents. These metabolites were mapped with high logarithm of odds (LOD) scores at the top of LG8, and progeny that was homozygous recessive for the candidate gene showed the elevated levels. We hypothesize that this was caused by inheritance of non‐functional alleles of enoyl‐CoA hydratase gene. Both examples of transgressive segregation, where some progeny significantly deviated from both parents, were caused by accumulation of recessive alleles.     

Characterization of pentraxin 3 in the horse and its expression in airways

The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses’ airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immuno-histochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cells. An alternative splicing of the second exon of PTX3 occurred, resulting in two forms of the protein: “spliced” (32 kDa) and “full length” (42 kDa). PTX3 was detected in BALF macrophages, neutrophils and bronchial epithelial cells. It was over-expressed in the BALF supernatant from R.A.O.-affected horses in crisis. However, dust was unable to induce PTX3 in BALF cells ex vivo, indicating that dust is an indirect inducer of PTX3. Dust exposure in-vivo induced PTX3 in BALF macrophages but there was no significant difference between healthy and R.A.O.-affected horses. Conversely, PTX3 was over-expressed in the bronchial epithelial cells from R.A.O.-affected horses in crisis. These data indicate a differential regulatory mechanism in inflammatory and bronchial epithelial cells and offer therapeutically interesting perspectives.