140 research outputs found
Different susceptibility of local Apulian and Calabrian grapevines to downy mildew and characterization of Plasmopara viticola populations
No full textDowny mildew, a severe grapevine disease worldwide, is caused by different cryptic species of Plasmopara viticola. Several approaches are under study to reduce the impact of chemicals in the disease management, including the selection of resistant genotypes for grapevine breeding. In this study, the susceptibility of six different local wine grape cultivars was assessed on leaves and bunches, in 2023, an year particularly favourable to the downy mildew epidemy. Based on McKinney's index (MKI: 37.3 to 52.6%), Marchione, Moscato reale, Maresco and Moscato di Terracina were more susceptible than Moscato di Trani, Trebbiano and Verdeca, classified as resistant ones (MKI: never exceeding 16.6%). Additionally, the genetic variability of P. viticola populations infecting grapevine in Apulia, Calabria and Lombardia was evaluated. Sporangia were collected from oil-spots in 26 vineyards (15 Apulia, 11 Calabria), during 2023 and 2024 years. The CAPS analysis was carried on restriction enzyme AseI profiles of the amplified DNA using the ITS1-O/ITS2, according to Rouxell et al. (2013). A total of 130 isolates and 20 DNA samples from oil spots sampled in Lombardia were analysed. All belong to the clade aestivalis, as also confirmed by BLASTn analysis of the ITS partial sequence of few representative isolate of Apulia and Calabria regions. These preliminary results suggest that the resistant behaviour of analysed grapevine genotypes is limited to P. viticola clade aestivalis and highlight the opportunity to preserve the local biodiversity for possible introduction of new P. viticola clades, currently absent
The role of selection pressure in shaping zoxamide resistance in Plasmopara viticola populations
No full textBACKGROUNDZ: oxamide, a beta-tubulin inhibitor, is widely used in vineyards to control downy mildew caused by the high-risk pathogen Plasmopara viticola. This study aimed to investigate the selection of zoxamide resistance and its characterization, providing practical insights for resistance management, through a twofold approach: a quantitative assessment of selection pressure effects on oospore populations and the molecular characterization of resistance-associated mutations in P. viticola strains. RESULTS: A total of 126 populations sampled from 57 vineyards mainly located in North-eastern Italy, were analyzed over a 6-year period (2017-2022). Based on toxicological parameters, 90% of the samples were fully sensitive to zoxamide (EC50 < 0.2 mg/L; EC95 and MIC<10 mg/L). Resistant individuals, able to germinate at 100 mg/L zoxamide, were detected in low frequency (<12%) within 13 samples. Only two samples showed a high frequency of resistant individuals (24-33%). Resistance was primarily found in vineyards treated more than four times per season with zoxamide. Partial sequencing of beta-tubulin gene revealed different polymorphisms at codon 239 associated with resistant isolates: the known C239S/G mutations, with the SG genotype being predominant, and a potential novel C239T mutation, not previously reported. CONCLUSION: This study highlighted a low risk of resistance under moderate fungicide application frequencies, indicating the importance of limiting fungicide applications to preserve sensitivity. The genetic diversity of resistance mechanisms, reflected in the various mutations in the beta-tubulin gene, underscores the need for a deeper investigation into the fitness of the different genotypes to evaluate resistance spread in P. viticola populations. (c) 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry
Oospore germination dynamics and disease forecasting model: an integrated approach for downy mildew management
No full textEvaluation of platelet function with the PFA-100 system in patients with congenital defects of platelet secretion
No full textThe template bleeding time is still the screening test for defects of platelet function, although it is an invasive and poorly reproducible technique. The PFA-100 measures platelet function at high shear. Whole blood is aspirated through a capillary to an aperture of a membrane coated with platelet agonists. The system measures the time required to obtain occlusion of the aperture by a platelet plug (closure time). We measured the closure times in the PFA-100 system and the bleeding time in seven patients with δ-storage pool deficiency, 10 patients with 'primary secretion defect' (not due to abnormalities of platelet granules or the arachidonate pathway), and 40 controls. Measurements were repeated 1 and 4 hours after intravenous infusion of desmopressin in six δ-storage pool deficiency and eight primary secretion defect patients. Baseline bleeding time and closure times with the collagen/epinephrine cartridge were longer in δ-storage pool deficiency and primary secretion defect patients than in controls. In contrast, closure times with the collagen/adenosine diphosphate cartridge were normal in both δ-storage pool deficiency and primary secretion defect patients. Treatment with desmopressin increased the plasma von Willebrand Factor levels, shortened the prolonged bleeding time, shortened the closure times with the collagen/adenosine diphosphate cartridge, and normalized the closure times with the collagen/epinephrine cartridge. Therefore, the PFA-100 test may be a less invasive alternative to the bleeding time in the diagnosis and therapeutic monitoring of patients with platelet secretion defects. The collagen/epinephrine cartridge is more sensitive than the collagen/adenosine diphosphate cartridge to defects of platelet secretion. Copyright (C) 1999 Elsevier Science Ltd
Low plasma levels of vitamin B-6 are independently associated with a heightened risk of deep-vein thrombosis
No full textBackground - Elevated plasma levels of total homocysteine (tHcy) before and after an oral methionine load (PML) are associated with an elevated risk of deep-vein thrombosis (DVT). We investigated whether plasma levels of B vitamins that are involved in Hcy metabolism are associated with an elevated risk of DVT. Methods and Results - We compared 397 cases with previous DVT with 585 matched healthy controls. The plasma levels of folate, vitamin B12, vitamin B6, and fasting and PML tHcy were measured. The ORs for DVT associated with high (>95th percentile) fasting levels and PML increases of tHcy were 2.1 (95% CI, 1.2 to 3.4) and 2.4 (95% CI, 1.5 to 3.9) after adjustment for established risk factors for DVT. Fasting plasma levels and PML increases in tHcy correlated negatively with vitamin levels. The crude OR for folate levels in the lowest quartile compared with the highest was 1.5 (95% CI, 1.1 to 2.1), and that for B6 levels in the lowest and second quartiles compared with the highest was 1.5 (95% CI, 1.0 to 2.1). However, after adjustment for established risk factors and fasting and PML tHcy, the ORs for B6 levels in the lowest and second quartiles only remained statistically significant (lowest quartile: OR, 1.8; 95% CI, 1.2 to 2.8; second quartile, OR, 1.9; 95% CI, 1.3 to 2.9). Conclusions - High fasting and PML tHcy and low vitamin B6 plasma levels are associated with an elevated risk for DVT independently of established risk factors for DVT. The association of low vitamin B6 levels with the risk for DVT is independent of fasting and PML tHcy levels
Enniatin B alters bovine polymorphonuclear leukocytes phagocytosis and extracellular reactive oxygen species production in vitro
No full textEnniatins (ENNs) affect human and animal health. Different ENN analogs have been identified, but Enniatin B (ENN B) is the most detected in foods and feeds. This study investigated the effect of ENN B on bovine polymorphonuclear leukocytes (PMNs) challenged with increasing ENN B concentrations (0.625, 1.25, 2.5, 5, and 10 μM). Bovine PMNs were isolated from the peripheral blood of dairy cows to evaluate the cell viability, chemotactic function, ability to phagocyte Gram+ and Gram– microorganisms, and extracellular Reactive Oxygens Species (ROS), with or without phorbol 12-myristate-13-acetate (PMA) as a pro-inflammatory challenge. Results demonstrated that ENN B did not affect bovine PMN viability and chemotactic activity at all concentrations (p = 0.952; p = 0.218, respectively). E. coli and S. aureus phagocytosis ability were reduced by ENN B at the highest concentrations (5 and 10 μM) compared to the negative control (p ≤ 0.001; p = 0.001, respectively). Extracellular ROS production was increased by ENN B challenge under physiological and pro-inflammatory conditions (p = 0.014; p < 0.001, respectively). In conclusion, ENN B did not exert cytotoxic effects on bovine PMNs, while reduced phagocytic ability and increased the production of extracellular ROS, highlighting its potential role as an immunomodulator of the bovine innate immune response in vitro. Implications: Emerging mycotoxin Enniatin B is a common grain contaminant worldwide that can exert cytotoxic and immunotoxic effects in animal cells. We hypothesized that Enniatin B could in vitro affect the bovine immune response. In our study, Enniatin B did not affect bovine polymorphonuclear cell viability and chemotaxis, while a reduction of phagocytosis and a modulation of extracellular reactive oxygen species were observed. The present study shows that Enniatin B in vitro exerts a potential role as an immunomodulator of the bovine innate immune response putting animals at an increased risk of infection diseases
Changes in the intestinal mucosal proteome of turkeys (Meleagris gallopavo) infected with haemorrhagic enteritis virus
No full textHaemorrhagic enteritis (HE) is a viral disease affecting intestinal integrity and barrier function in turkey (Meleagris gallopavo) and resulting in a significant economic loss. Sequential Windowed Acquisition of All Theoretical Fragment Ion Mass Spectra (SWATH-MS) was applied to identify crucial proteins involved in HE infection. A total of 938 proteins were identified and used to generate a reference library for SWATH-MS analysis. In total, 523 proteins were reliably quantified, and 64 proteins were found to be differentially expressed, including 49 up-regulated and 15 down-regulated proteins between healthy and HE-affected intestinal mucosa. Functional analysis suggested that these proteins were involved in the following categories of cellular pathways and metabolisms: 1) energy pathways; 2) intestine lipid and amino acid metabolism; 3) oxidative stress; 4) intestinal immune response. Major findings of this study demonstrated that natural HE infection is related to the changes in abundance of several proteins involved in cell-intrinsic immune defense against viral invasion, systemic inflammation, modulation of excessive inflammation, B and T cell development and function and antigen presentation. mRNA quantitative expression demonstrated that most of the proteins involved in innate immunity that were found to be differentially abundant were produced by intestinal mucosa, suggesting its direct involvement in immune defences against HE infection
Effects of milk extracellular vesicles from Holstein Friesian and Brown Swiss heat-stressed dairy cows on bovine mammary epithelial cells
No full textThe increase in ambient temperature is responsible for a behavioral, physiological and metabolic responses known as heat stress, which affects dairy cows' general well-being, health, reproduction, and productivity. Focusing on the functioning of the mammary gland, attention has been recently paid to a new method of cell-cell communication mediated by extracellular vesicles, which with their cargo can affect the target cells' phenotypic traits, behavior, and biological functions. This study investigated whether the small extracellular vesicles (sEVs) isolated from milk of heat-stressed Holstein Friesian (H) and Brown Swiss (B) cows affect the cellular response of a bovine mammary epithelial cell line (BME-UV1). To this purpose, 8 mid-lactating cows, 4 of each breed fed the same diet and kept in the same barn, which experienced the same hyperthermia during a natural heat wave, were chosen to collect 2 milk different samples: under thermoneutrality (TN 1st day) and under heat stress (HS 8th day) conditions. The sEVs were isolated from skim milk samples through differential centrifugations, characterized for size and concentration by nanoparticle tracking analysis. Integrity of the milk sEVs membranes was evaluated by transmission electron microscopy and presence of EV markers through Western blotting. Then BME-UV1 cells were incubated for 24 h with different pooled milk sEVs (H-TN, H-HS, B-TN, B-HS). Cell viability and apoptosis assay, reactive oxygen species production, and mRNA expression of heat shock proteins and antioxidant genes by RT-qPCR were determined. In vivo results showed an increase in rectal temperature and respiration rate, a reduction in milk yield both for H and B dairy cows, with a lowest decrease observed in B cows compared with H cows. In vitro results of BME-UV1 cells treated with milk sEVs H-HS and B-HS showed an alteration of the cell viability and metabolic activity, by reducing or increasing ROS accumulation, and suppressing or increasing the expression of stress-associated genes thereby modulating the response of BME-UV1 according to the animals' thermal condition and the breed. These findings indicated that the small vesicles of Brown milk triggered cellular defense against heat stress, supporting the Brown Swiss breed's thermotolerance
Evaluation of the PFA-100 (R) system in the diagnosis and therapeutic monitoring of patients with von Willebrand disease
No full textWe have evaluated platelet function at high shear with the PFA-100® system in different subtypes of von Willebrand disease (vWD), before and after the intravenous infusions of desmopressin or a factorVIII/von Willebrand factor (vWF) concentrate. Closure times with the PFA-100® system were determined for both the collagen/ADP and the collagen/epinephrine cartridges in 52 patients with vWD (9 type 1 'platelet normal', 5 type 1 'platelet-discordant', 8 type 1 'platelet-low', 6 type 2A, 9 type 2B, 6 type 2M Vicenza, 6 type 3 and 3 acquired vWD) and 40 controls. Measurements were repeated 1 and 4 h after the i.v. infusion of desmopressin (0.3 μg/Kg) in 26 patients with types 1, type 2M Vicenza or type 2A vWD, or of a factorVIII/vWF concentrate (Alphanate HT, 60 U/Kg) in 4 patients with type 3 vWD. At all time points, vWF plasma levels and the bleeding time (Symplate II) were also determined. Baseline closure times were longer in vWD patients than in controls with both the collagen/ADP and the collagen/ epinephrine cartridges. The sensitivity of the PFA-100® system (88% and 87% with the two cartridges) was higher than that of the bleeding time (65%). Treatment with desmopressin normalized the closure times in patients with type 1 'platelet-normal' or type 2M Vicenza vWD, had no significant effects in patients with type 1 'platelet-low', type 1 'platelet-discordant' or type 2A vWD. Infusion of a factorVII/vWF concentrate in patients with type 3 vWD slightly shortened their prolonged closure rimes, In general changes in PFA-100® were paralleled by shortenings of the bleeding times and increases in plasma vWF levels. The PFA-100® test reflects vWF-dependent platelet function under high shear stress and could be useful in the diagnosis and therapeutic monitoring of patients with vWD
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