100 research outputs found
Feeding broiler chickens with arginine above recommended levels: effects on growth performance, metabolism, and intestinal microbiota
BackgroundArginine is an essential amino acid for chickens and feeding diets with arginine beyond the recommended levels has been shown to influence the growth performance of broiler chickens in a positive way. Nonetheless, further research is required to understand how arginine supplementation above the widely adopted dosages affects metabolism and intestinal health of broilers. Therefore, this study was designed to assess the effects of arginine supplementation (i.e., total arginine to total lysine ratio of 1.20 instead of 1.06-1.08 recommended by the breeding company) on growth performance of broiler chickens and to explore its impacts on the hepatic and blood metabolic profiles, as well as on the intestinal microbiota. For this purpose, 630 one-day-old male Ross 308 broiler chicks were assigned to 2 treatments (7 replicates each) fed a control diet or a crystalline L-arginine-supplemented diet for 49 d.ResultsCompared to control birds, those supplemented with arginine performed significantly better exhibiting greater final body weight at D49 (3778 vs. 3937 g; P < 0.001), higher growth rate (76.15 vs. 79.46 g of body weight gained daily; P < 0.001), and lower cumulative feed conversion ratio (1.808 vs. 1.732; P < 0.05). Plasma concentrations of arginine, betaine, histidine, and creatine were greater in supplemented birds than in their control counterparts, as were those of creatine, leucine and other essential amino acids at the hepatic level. In contrast, leucine concentration was lower in the caecal content of supplemented birds. Reduced alpha diversity and relative abundance of Firmicutes and Proteobacteria (specifically Escherichia coli), as well as increased abundance of Bacteroidetes and Lactobacillus salivarius were found in the caecal content of supplemented birds.ConclusionsThe improvement in growth performance corroborates the advantages of supplementing arginine in broiler nutrition. It can be hypothesized that the performance enhancement found in this study is associated with the increased availability of arginine, betaine, histidine, and creatine in plasma and the liver, as well as to the ability of extra dietary arginine to potentially ameliorate intestinal conditions and microbiota of supplemented birds. However, the latter promising property, along with other research questions raised by this study, deserve further investigations
Transcranial alternating current stimulation and sports performance: an explorative study of the association with the genetic background
Verbal Fluency in Mild Alzheimer's Disease: Transcranial Direct Current Stimulation over the Dorsolateral Prefrontal Cortex
Background: Recent studies showed that in healthy controls and in aphasic patients inhibitory trains of repetitive transcranial magnetic stimulation (rTMS) over the right prefrontal cortex can improve phonemic fluency performance, while anodal transcranial direct current stimulation (tDCS) over the left prefrontal cortex can improve performance in naming and semantic fluency tasks.
Objective: This study aimed at investigating the effects of cathodal tDCS over the left or the right dorsolateral prefrontal cortex (DLPFC) on verbal fluency tasks (VFT) in patients with mild Alzheimer’s Disease (AD).
Methods: Forty mild AD patients participated in the study (mean age 73.17 ± 5.61 years). All participants underwent cognitive baseline tasks and a VFT twice. Twenty patients randomly received cathodal tDCS to the left or the right DLPFC, and twenty patients were assigned to a control group in which only the two measures of VFT were taken, without the administration of the tDCS.
Results: A significant improvement of performance on the VFT in AD patients was present after tDCS over the right DLPFC (p=.001). Instead, no difference was detected between the two VFTs sessions after tDCS over the left DLPFC (p=.42). Furthermore, these results cannot be related to task learning effects, since no significant difference was found between the two VFT sessions in the control group (p= .73).
Conclusions: These data suggest that tDCS over DLPFC can improve VFT performance in AD patients. A hypothesis is that tDCS enhances adaptive patterns of brain activity between functionally connected areas
Synthesis and study of novel multifunctional cyclodextrin‐deferasirox hybrids
Metal dyshomeostasis is central to a number of disorders that result from, inter alia, oxidative stress protein misfolding, and cholesterol dyshomeostasis. In this respect, metal deficiencies are usually readily corrected by treatment with supplements, whereas metal overload can be overcome by the use of metal‐selective chelation therapy. Deferasirox, 4‐[(3Z,5E)‐3,5‐bis(6‐oxo‐1‐cyclohexa‐2,4‐dienylidene)‐1,2,4‐triazolidin‐1‐yl]benzoic acid, Exjade, or ICL670, is used clinically to treat hemosiderosis (iron overload), which often results from multiple blood transfusions. Cyclodextrins are cyclic glucose units that are extensively used in the pharmaceutical industry as formulating agents as well as for encapsulating hydrophobic molecules such as in the treatment of Niemann Pick C or for hypervitaminosis. We have conjugated deferasirox, via an amide coupling reaction, to both 6A‐amino‐6A‐deoxy‐β‐cyclodextrin and 3A‐amino‐3A‐deoxy‐2A(S),3A(R)‐β‐cyclodextrin, at the upper and lower rim respectively creating hybrid molecules with dual properties, capable of both metal chelation and cholesterol encapsulation. Our findings emphasize the importance of the conjugation of β‐cyclodextrin with deferasirox to significantly improve the biological properties and reduce the cytotoxicity of this drug
Desorption Electrospray Ionization Mass Spectrometry Reveals Lipid Metabolism of Individual Oocytes and Embryos.
Alteration of maternal lipid metabolism early in development has been shown to trigger obesity, insulin resistance, type 2 diabetes and cardiovascular diseases later in life in humans and animal models. Here, we set out to determine (i) lipid composition dynamics in single oocytes and preimplantation embryos by high mass resolution desorption electrospray ionization mass spectrometry (DESI-MS), using the bovine species as biological model, (ii) the metabolically most relevant lipid compounds by multivariate data analysis and (iii) lipid upstream metabolism by quantitative real-time PCR (qRT-PCR) analysis of several target genes (ACAT1, CPT 1b, FASN, SREBP1 and SCAP). Bovine oocytes and blastocysts were individually analyzed by DESI-MS in both positive and negative ion modes, without lipid extraction and under ambient conditions, and were profiled for free fatty acids (FFA), phospholipids (PL), cholesterol-related molecules, and triacylglycerols (TAG). Principal component analysis (PCA) and linear discriminant analysis (LDA), performed for the first time on DESI-MS fused data, allowed unequivocal discrimination between oocytes and blastocysts based on specific lipid profiles. This analytical approach resulted in broad and detailed lipid annotation of single oocytes and blastocysts. Results of DESI-MS and transcript regulation analysis demonstrate that blastocysts produced in vitro and their in vivo counterparts differed significantly in the homeostasis of cholesterol and FFA metabolism. These results should assist in the production of viable and healthy embryos by elucidating in vivo embryonic lipid metabolism
Metabolic and microbiota response to arginine supplementation and cyclic heat stress in broiler chickens
Little attention has been paid to the biological role of arginine and its dietary supplementation in broilers under heat stress (HS) conditions. Therefore, the main aim of this study was to assess the response of broilers to arginine supplementation and cyclic HS, with a focus on liver, pectoral muscle, and blood metabolic profiles and the cecal microbiota. Day-old male Ross 308 broilers (n = 240) were placed in 2 rooms with 12 pens each for a 44-day trial. Pens were assigned to one of two groups (6 pens/group/room): the control group (CON) was given a basal diet in mash form and the treated group (ARG) was fed CON diet supplemented with crystalline L-arginine. The total arginine:lysine ratio of CON diet ranged between 1.02 and 1.07, while that of ARG diet was 1.20. One room was constantly kept at thermoneutral (TN) conditions, while the birds in the other room were kept at TN conditions until D34 and subjected to cyclic HS from D35 onwards (∼34°C; 9:00 A.M.–6:00 P.M.). Blood, liver, Pectoralis major muscle, and cecal content were taken from 2 birds per pen (12 birds/group/room) for metabolomics and microbiota analysis. Growth performance data were also collected on a pen basis. Arginine supplementation failed to reduce the adverse effects of HS on growth performance. Supplemented birds showed increased levels of arginine and creatine in plasma, liver, and P. major and methionine in liver, and reduced levels of glutamine in plasma, liver, and P. major. HS altered bioenergetic processes (increased levels of AMP and reduced levels of fumarate, succinate, and UDP), protein metabolism (increased protein breakdown to supply the liver with amino acids for energy production), and promoted the accumulation of antioxidant and protective molecules (histidine-containing dipeptides, beta-alanine, and choline), especially in P. major. Arginine supplementation may have partially counterbalanced the effects of HS on energy homeostasis by increasing creatine levels and attenuating the increase in AMP levels, particularly in P. major. It also significantly reduced cecal observed diversity, while HS increased alpha diversity indices and affected beta diversity. Results of taxonomic analysis at the phylum and family level are also provided
Rapporto tecnico e delle attività Campagna Oceanografica SAFE 2022
Le attività scientifiche realizzate nell’ambito della Campagna Oceanografica SAFE 2022 si inseriscono all’interno dell’Obiettivo Realizzativo 1 (OR1) del progetto PON_03 ‘Marine Hazard’ suddiviso in quattro Work Packages (WPs) articolati nel seguente modo:
WP1 Studio dei potenziali giacimenti da sistemi idrotermali (GSI) sottomarini presenti nel Mar Tirreno sud-orientale e nello Stretto di Sicilia;
WP2 Progetto Pilota di caratterizzazione geochimica ed ecologica dei GSI sul Palinuro Seamount;
WP3 Sistema Acustico per la Rivelazione di Fenomeni di Idrotermalismo Sottomarino;
WP4 Analisi di possibili impatti nell’ambiente marino e sottomarino.
I dati ottenuti dalla Campagna Oceanografica SAFE 2022 contribuiranno ad arricchire le conoscenze sulla caratterizzazione chimico-fisica, biologica e microbiologica dei depositi e dei sistemi idrotermali. Le attività di ricerca si prospettano di fornire un quadro di conoscenze dettagliato e completo di ambienti che rappresentano oltre che possibili geositi e habitat prioritari anche un laboratorio per la ricerca e la scoperta di nuove biomolecole di interesse biotecnologico e l’individuazione di bioindicatori di attività geotermali e di marine hazard
Interactive hyperspectral approach for exploring and interpreting DESI-MS images of cancerous and normal tissue sections
Azole-Resistance in Aspergillus terreus and Related Species: An Emerging Problem or a Rare Phenomenon?
Raquel Sabino was not included as an author in the published article. It was corrected a posteriori.Erratum in - Corrigendum: Azole-Resistance in Aspergillus terreus and Related Species: An Emerging Problem or a Rare Phenomenon? [Front Microbiol. 2018] Front Microbiol. 2019 Jan 14;9:3245. doi: 10.3389/fmicb.2018.03245. eCollection 2018.Disponível em: https://www.frontiersin.org/articles/10.3389/fmicb.2018.03245/fullFree PMC Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5882871/ | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6340063/Objectives: Invasive mold infections associated with Aspergillus species are a significant cause of mortality in immunocompromised patients. The most frequently occurring aetiological pathogens are members of the Aspergillus section Fumigati followed by members of the section Terrei. The frequency of Aspergillus terreus and related (cryptic) species in clinical specimens, as well as the percentage of azole-resistant strains remains to be studied. Methods: A global set (n = 498) of A. terreus and phenotypically related isolates was molecularly identified (beta-tubulin), tested for antifungal susceptibility against posaconazole, voriconazole, and itraconazole, and resistant phenotypes were correlated with point mutations in the cyp51A gene. Results: The majority of isolates was identified as A. terreus (86.8%), followed by A. citrinoterreus (8.4%), A. hortai (2.6%), A. alabamensis (1.6%), A. neoafricanus (0.2%), and A. floccosus (0.2%). One isolate failed to match a known Aspergillus sp., but was found most closely related to A. alabamensis. According to EUCAST clinical breakpoints azole resistance was detected in 5.4% of all tested isolates, 6.2% of A. terreus sensu stricto (s.s.) were posaconazole-resistant. Posaconazole resistance differed geographically and ranged from 0% in the Czech Republic, Greece, and Turkey to 13.7% in Germany. In contrast, azole resistance among cryptic species was rare 2 out of 66 isolates and was observed only in one A. citrinoterreus and one A. alabamensis isolate. The most affected amino acid position of the Cyp51A gene correlating with the posaconazole resistant phenotype was M217, which was found in the variation M217T and M217V. Conclusions:Aspergillus terreus was most prevalent, followed by A. citrinoterreus. Posaconazole was the most potent drug against A. terreus, but 5.4% of A. terreus sensu stricto showed resistance against this azole. In Austria, Germany, and the United Kingdom posaconazole-resistance in all A. terreus isolates was higher than 10%, resistance against voriconazole was rare and absent for itraconazole.This work was supported by ECMM, ISHAM, and EFISG and in
part by an unrestricted research grant through the Investigator
Initiated Studies Programof Astellas, MSD, and Pfizer. This study
was fundet by the Christian Doppler Laboratory for invasive
fungal infections.info:eu-repo/semantics/publishedVersio
Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star
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