Phaidra - University of Veterinary Medicine Vienna
Not a member yet
3528 research outputs found
Sort by
Advancing Glycyrrhiza glabra L. Cultivation and Hairy Root Transformation and Elicitation for Future Metabolite Overexpression
No full textThe production of valuable bioactive compounds in the medicinal plant Glycyrrhiza glabra L. (G. glabra) would benefit from biotechnological approaches for the cultivation and induction of metabolite-producing hairy roots. Germination trials were tested to overcome seed dormancy, achieving high germination rates with sulfuric acid treatment. Hairy root cultures of cotyledons using Rhizobium rhizogenes strain 1724 showed the highest transformation efficiency. A fast-growing line, line S, was subsequently exposed to light treatments (red, blue, and blue and red combined) to evaluate their effects on growth, phenolic content, and Ferric Reducing Antioxidant Power (FRAP). Hairy root cultures grown in blue light and in blue and red light combined had higher growth rates than those grown in red light only or in control conditions (dark). FRAP increased over time under all light treatments, including the control, and those cultures exposed to blue and red light combined had higher FRAP than the control. These findings provide valuable insights into conditions for optimal seed germination and hairy root transformation. Treatment of the line S with different qualities of light induced changes in antioxidant capacity and phenolic content, indicating promise for its use in upregulating secondary metabolite production in G. glabra for future biotechnological applications
Residual Nitrite, Nitrate, and Volatile N-Nitrosamines in Organic and Conventional Ham and Salami Products
No full textNitrite and nitrate in meat products may be perceived negatively by consumers. These compounds can react to form carcinogenic volatile N-nitrosamines. "Nitrite-free" (i.e., uncured) organic meat products may contain nitrate from natural sources (e.g., spices and water). We studied the quality of ham and salami (conventional cured; organic cured; organic uncured). Residual nitrite and nitrate, volatile N-nitrosamines, microbial load, surface color, water activity, and pH were determined, considering one week of refrigerated storage in open or unopened packages. Residual nitrite and nitrate in organic, uncured salami were similar to cured salami, presumably from the addition of herbs and spices and nitrate reduction by nitrate reductase from microorganisms. For cooked ham, residual nitrite was significantly lower in the organic, uncured sample, while residual nitrate was not detected. N-nitrosodiphenylamine was detected in all samples at day 0, exceeding, in three out of five cured and both uncured products, the US legal limit of 10 µg/kg of volatile N-nitrosamines in foods. This finding warrants further investigation. The microbial load in salami products was dominated by bacteria from starter cultures. In ham, a slight increase in total aerobic count and lactic acid bacteria during storage was noted. Overall, the microbial quality of the products was as expected for the respective product types
Point-of-care ClotPro thromboelastography to determine bleeding risk in two cats with factor XII deficiency
No full textFactor XII (FXII) deficiency is a rare autosomal recessive genetic disorder in cats, leading to singular prolonged activated partial thromboplastin clotting time (aPTT) without increased bleeding risk. This case series describes two cats diagnosed with FXII deficiency using the ClotPro system, a point-of-care viscoelastic coagulation test. Both cats exhibited significantly prolonged aPTT and intrinsic pathway clotting time but maintained normal clot strength, as indicated by thromboelastography (TEG). FXII deficiency was confirmed through quantitative ELISA measurement. Despite prolonged clotting times, the cats did not demonstrate clinical bleeding, suggesting that FXII deficiency does not increase bleeding risk. However, larger controlled studies are necessary to further investigate the utility of TEG in cats with FXII deficiency or other coagulation disorders.This study addresses the diagnostic challenges associated with FXII deficiency, a condition that can lead to misinterpretation of coagulation results and unnecessary treatments. It highlights the application of the ClotPro system in feline medicine, providing deeper insights into coagulation dynamics and confirming that FXII deficiency does not inherently increase bleeding risk despite prolonged clotting times
Fibroblast growth factor 23 and fibroblast growth factor receptor 4 promote cardiac metabolic remodeling in chronic kidney disease
No full textChronic kidney disease (CKD) is a global health epidemic that greatly increases mortality due to cardiovascular disease. Left ventricular hypertrophy (LVH) is an important mechanism of cardiac injury in CKD. High serum levels of fibroblast growth factor (FGF) 23 in patients with CKD may contribute mechanistically to the pathogenesis of LVH by activating FGF receptor (FGFR) 4 signaling in cardiac myocytes. Mitochondrial dysfunction and cardiac metabolic remodeling are early features of cardiac injury that predate development of hypertrophy, but these mechanisms have been insufficiently studied in models of CKD. We found in wild-type mice with CKD induced by adenine diet, that morphological changes occurred in mitochondrial structure and cardiac mitochondrial and that metabolic dysfunction preceded the development of LVH. In bioengineered cardio-bundles and neonatal rat ventricular myocytes grown in vitro, FGF23-mediated activation of FGFR4 caused mitochondrial pathology, characterized by increased bioenergetic stress and increased glycolysis that preceded the development of cellular hypertrophy. The cardiac
metabolic changes and associated mitochondrial alterations in mice with CKD were prevented by global and cardiac-specific deletion of FGFR4. Our findings indicate that metabolic remodeling and mitochondrial dysfunction are early cardiac complications of CKD that precede structural remodeling of the heart. Mechanistically, FGF23-mediated activation of FGFR4 causes mitochondrial dysfunction, suggesting that early pharmacologic inhibition of FGFR4 might serve as novel therapeutic intervention to prevent development of LVH and heart failure in patients with CKD
Large-scale phenotypic and genomic analysis of Listeria monocytogenes reveals diversity in the sensitivity to quaternary ammonium compounds but not to peracetic acid.
No full textListeria monocytogenes presents a significant concern for the food industry due to its ability to persist in the food processing environment. One of the factors contributing to its persistence is decreased sensitivity to disinfectants. Our objective was to assess the diversity of L. monocytogenes sensitivity to food industry disinfectants by testing the response of 1,671 L. monocytogenes isolates to quaternary ammonium compounds (QACs) and 414 isolates to peracetic acid (PAA) using broth microdilution and growth curve analysis assays, respectively, and to categorize the isolates into sensitive and tolerant. A high phenotype-genotype concordance (95%) regarding tolerance to QACs was obtained by screening the genomes for the presence of QAC tolerance-associated genes bcrABC, emrE, emrC, and qacH. Based on this high concordance, we assessed the QAC genes\u27 dissemination among publicly available L. monocytogenes genomes (n = 39,196). Overall, QAC genes were found in 23% and 28% of the L. monocytogenes collection in this study and in the global data set, respectively. bcrABC and qacH were the most prevalent genes, with bcrABC being the most detected QAC gene in the USA, while qacH dominated in Europe. No significant differences (P> 0.05) in the PAA tolerance were detected among isolates belonging to different lineages, serogroups, clonal complexes, or isolation sources, highlighting limited variation in the L. monocytogenes sensitivity to this disinfectant. The present work represents the largest testing of L. monocytogenes sensitivity to important food industry disinfectants at the phenotypic and genomic level, revealing diversity in the tolerance to QACs while all isolates showed similar sensitivity to PAA.Contamination of Listeria monocytogenes within food processing environments is of great concern to the food industry due to challenges in eradicating the isolates once they become established and persistent in the environment. Genetic markers associated with increased tolerance to certain disinfectants have been identified, which alongside other biotic and abiotic factors can favor the persistence of L. monocytogenes in the food production environment. By employing a comprehensive large-scale phenotypic testing and genomic analysis, this study significantly enhances the understanding of the L. monocytogenes tolerance to quaternary ammonium compounds (QACs) and the genetic determinants associated with the increased tolerance. We provide a global overview of the QAC genes prevalence among public L. monocytogenes sequences and their distribution among clonal complexes, isolation sources, and geographical locations. Additionally, our comprehensive screening of the peracetic acid (PAA) sensitivity shows that this disinfectant can be used in the food industry as the lack of variation in sensitivity indicates reliable effect and no apparent possibility for the emergence of tolerance
tRNA binding to Kti12 is crucial for wobble uridine modification by Elongator
No full textIn yeast, tRNA modifications that are introduced by the Elongator complex are recognized by zymocin, a fungal tRNase killer toxin that cleaves the anticodon. Based on zymocin resistance conferred by mutations in KTI12, a gene coding for an Elongator interactor, we further examined the yet vaguely defined cellular role of Kti12. Guided by structural similarities between Kti12 and PSTK, a tRNA kinase involved in selenocysteine synthesis, we identified conserved basic residues in the C-terminus of Kti12, which upon site-directed mutagenesis caused progressive loss of tRNA binding in vitro. The inability of Kti12 to bind tRNA led to similar phenotypes caused by Elongator inactivation in vivo. Consistently, tRNA binding deficient kti12 mutants drastically suppressed Elongator dependent tRNA anticodon modifications and reduced the capacity of Kti12 to interact with Elongator. We further could distinguish Elongator unbound pools of Kti12 in a tRNA dependent manner from bound ones. In summary, the C-terminal domain of Kti12 is crucial for tRNA binding and Kti12 recruitment to Elongator, which are both requirements for Elongator function suggesting Kti12 is a tRNA carrier that interacts with Elongator for modification of the tRNA anticodon
Testosterone dynamics of migratory birds during stopover
No full textBirds migrating in the spring must balance energy with hormonal preparations in anticipation of the forthcoming breeding season. We investigated the relationships between testosterone, body condition, sociality, territoriality and fueling rates in Western Subalpine Warbler (Curruca iberiae) males during a trans-Saharan stopover. Baseline testosterone was highly variable in correspondence with the transitional nature of spring stopover. Some individuals reached breeding testosterone levels while others had undetectable levels. Testosterone varied with body condition suggesting an endocrine-energy link during migration. Simulated territory intrusions induced an increase of testosterone up to physiological maxima- a similar pattern to breeding contexts. Testosterone was negatively associated with territorial male density, suggesting a \u27dear enemy\u27 effect related to the daily variation in social stability. In repeatedly-sampled individuals, stopover duration and fueling rate were not correlated with baseline testosterone. However, as testosterone decreased, body condition increased. This suggests that stopover territoriality may reduce the reported negative effects of chronically high testosterone. Our data supports the hypothesis that hormonal preparation for breeding may already occur during stopover, and that this is largely linked to body condition. In this system, the endocrine-energy relationship is likely maintained by stopover territoriality. We conclude that male-male social contexts are modulated in similar ways during spring migration as during the breeding life history stage
Cold aortic flush after ventricular fibrillation cardiac arrest reduces inflammatory reaction but not neuronal loss in the pig cerebral cortex
No full textThis study aims to retrospectively compare two resuscitation methods (extracorporeal cardiopulmonary resuscitation (ECPR) vs. emergency preservation and resuscitation (EPR)) by pathohistologically assessing pig brains in a ventricular fibrillation cardiac arrest (VFCA) model. In prospective studies from 2004 to 2006, swine underwent VFCA for 13 (n = 6), 15 (n = 14) or 17 (n = 6) minutes with ECPR (ECPR13, ECPR15 and ECPR17). Another 15 min VFCA group (n = 8) was resuscitated with EPR and chest compressions (EPR15 + CC). Brains of animals surviving for nine days (ECPR13 n = 4, ECPR15 n = 2, ECPR17 n = 1, EPR15 + CC n = 7) were harvested. Eight different brain regions were analyzed with the image analysis software QuPath using HE-staining, GFAP- and Iba1-immunohistochemistry. Only ECPR13 and EPR15 + CC animals were included in statistical analysis, due to low survival rates in the other groups. All VFCA samples showed significantly fewer viable neurons compared to shams, but no significant differences between ECPR13 and EPR15 + CC animals were observed. ECPR13 animals showed significantly more glial activation in all cerebral cortex regions compared to shams and in occipital, temporal and parietal cortex compared to EPR15 + CC. In conclusion, EPR + CC resulted in a significantly reduced inflammatory reaction in cerebral cortex compared to ECPR but did not influence the extent of neuronal death after VFCA
Antimicrobial and Metal Resistance Genes in Bacteria Isolated from Mine Water in Austria
No full textBackground/Objectives: Microbiomes surrounding mining sites have been found to harbor both antibiotic resistance genes and metal resistance genes. Within the "One Health" framework, which spans human, veterinary and environmental health, it is crucial to determine whether bacterial metal resistance (MR) genes can independently trigger antimicrobial resistance (AMR) or if they are linked to AMR genes and co-transferred horizontally. Methods and Results: Bacteria were isolated from an active and an inactive mining site in the alpine region of Austria. Most of the isolated bacteria harbored antimicrobial and metal resistance genes (88%). MALDI-TOF and whole genome sequencing (WGS) revealed that species from the Pseudomonadaceae family were the most identified, accounting for 32.5%. All Pseudomonas spp. carried AMR genes from the mex family, which encode multidrug efflux pumps. ?-lactamase production encoded by bla genes were detected as the second most common (26%). The same AMR genes have often been detected within a particular bacterial genus. No tetracycline resistance gene has been identified. Among metal resistance genes, rufB (tellurium resistance) was the most prevalent (33%), followed by recGM (selenium resistance, 30%), copA (copper resistance, 26%), and mgtA (magnesium and cobalt resistance, 26%). Notably, the mer gene family (mercury resistance) was found exclusively in isolates from the inactive mining site (n = 6). In addition, genes associated with both antimicrobial and metal resistance, including arsBM, acrD, and the mer operon, were identified in 19 out of the 43 isolates. Conclusions: Bacteria isolated from mine water harbored both MR and AMR genes. Given the exceptional diversity of bacterial species in these settings, 16S rRNA gene sequence analysis is the recommended method for accurate species identification. Moreover, the presence of multi-drug transporters and transferable resistance genes against critically important antimicrobials such as fluoroquinolones and colistin identified in these environmental bacteria emphasizes the importance of retrieving environmental data within the "One Health" framework
Relative telomere length in dairy calves and dams undergoing two different methods of weaning and separation after three months of contact
No full textTelomere length (i.e., the length of the repeated sequences of DNA at the end of chromosomes) is a promising indicator of overall stress. Our study aimed to compare the effects of a stress-inducing separation process between dams and their calves, with either a gradual or a nose-flap separation method after a three-months dam-calf contact since calving, on relative telomere length (RTL). Due to their nature, the nose-flap and gradual separation method have different effects on behaviour, stress hormone levels and physical development during and after dam-calf separation, which requires an overall measure of the weaning and separation stress during both procedures. We also investigated correlations between behavioural and other physiological stress indicators on RTL. We found no significant effect of the weaning and separation method on RTL in dairy calves after weaning and separation from their dams, but a tendency for shorter RTL in gradually separated dams compared to nose-flap separated dams. No correlations between behavioural and other physiological stress indicators and RTL were found, which may be due to a short interval between the two RTL measurement points. Future studies should aim to analyse the effect of various separation methods over a longer period and preferably include a non-separation group as reference