48 research outputs found

    Branched-Chain Amino Acids

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    Our study is focused on evaluation and use of the most effective and correct nutrients. In particular, our attention is directed to the role of certain amino acids in cachectic patients.During parenteral nutrition in humans, physician already associates in the PN-bags different formulations including amino acids, lipids and glucose solutions or essential amino acids solution alone or exclusively branched-chain amino acids (BCAA). Studies investigated the effects of dietary BCAA ingestion on different diseases and conditions such as obesity and metabolic disorders, liver disease, muscle atrophy, cancer, impaired immunity or injuries (surgery, trauma, burns, and sepsis). BCAAs have been shown to affect gene expression, protein metabolism, apoptosis and regeneration of hepatocytes, and insulin resistance. They have also been shown to inhibit the proliferation of liver cancer cells in vitro, and are essential for lymphocyte proliferation and dendritic cell maturation. Oral or parenteral administration of these three amino acids will allow us to evaluate the real efficacy of these compounds during a therapy to treat malnutrition in subjects unable to feed themselves

    The saponification of lauric acid with calcium soaps as an alternative to in-feed antibiotics in post-weaning piglets

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    In the search for the reduction of antibiotics in farm animals, a concept was developed based on studies with medium-chain fatty acid with 6-12 atoms (MCFA). In particular, they have been shown to exhibit against Gram+ bacteria in piglets at relatively high concentrations. However they can be hardly used as such because of their repellent odour and taste and for their rapid absorption in upper gastrointestinal tract. These problems could be overcome by the generation of monoacylglycerol, but esterification is usually carried out on a silica base, which reduces the concentration of FA, therefore limiting the antibacterial effects. Our hypothesis is that the saponification with calcium salts might positively affect their concentration in the GIT. The aim of the present study was to examine the effects of Laurate calcium soap (C12-Ca soap) on growth performance and health of post-weaning piglets. At weaning, 192 crossbreed Topics piglets were assigned to 3 experimental groups consisting of 16 pens (4 pigs/pen each): CTR (negative control), T1 (basal diet plus Amoxycillin at 400 mg/kg), and T2 (basal diet plus C12-Ca soap at 1 kg/ton). Gain and feed consumption did not differ among groups. Feed efficiency was higher in T1 (0,61) and T2 (0,58) than CTR (0,51) (P<0,01). Mortality was 0 in T1, and reduced in T2 (4,7%) compared to CTR (10,9%). These preliminary results suggest that saponification of MCFA may be a valuable alternative to in-feed antibiotics, used for growth promotion, and even for enhancing health in post-weaning piglets

    Sheep head frame validation for CT and MRI studies

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    Abstract IntroductionsAim of EDEN 2020 project’s Milestone 5 is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model.Materials and methodsIn this part of the study two fresh sheep’s head from the local slaughter were used.The heads were located into an ad hoc Frame system based on anatomical measures and CT images, producted by Renishaw plc partner in this project. The frame was adapted and every components were checked for the ex vivo validation tests.CT imaging was taken in Lodi at Università degli studi di Milano, Facoltà di Medicina Veterinaria, with CT scanner and MRI imaging was taken in La Cittadina, CremonaResultsSystem validation was approved by the ex vivo trial.The frame system doesn’t compromise the imaging acquisition in MRI and CT systems.Every system components are functional to their aims.DiscussionThe Frame system is adapted to the sheep head. It is composed by elements able to lock the head during the imaging acquisition. Frame system is characterized by a support base helpings the animals to keep the head straight forward during imaging time, under general anesthesia. The design of these device support the airways anatomy, avoiding damaging or obstruction of airflows during anesthesia period.The role of elements like mouth bar and ovine head pins is to lock the head in a stable position during imaging acquisition; fixing is guaranteed by V shape head pins, that are arranged against the zygomatic arches. Lateral compression forces to the cranium, and the V shape pins avoid the vertical shifting of the head and any kind of rotations. (fig. 1

    Experimental Determination of Momentum-Resolved Electron-Phonon Coupling

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    We provide a novel experimental method to quantitatively estimate the electron-phonon coupling and its momentum dependence from resonant inelastic x-ray scattering (RIXS) spectra based on the detuning of the incident photon energy away from an absorption resonance. We apply it to the cuprate parent compound NdBa2_2Cu3_3O6_6 and find that the electronic coupling to the oxygen half-breathing phonon mode is strongest at the Brillouin zone boundary, where it amounts to ∼0.17\sim 0.17 eV, in agreement with previous studies. In principle, this method is applicable to any absorption resonance suitable for RIXS measurements and will help to define the contribution of lattice vibrations to the peculiar properties of quantum materials.Comment: 6 pages, 3 figure

    Derivation of canine hepatocyte in vitro models to study Branched-Chain Amino Acid effects on liver functions.

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    Branched chain amino acids (BCAA), have been shown to affect human gene expression, proteinmetabolism, apoptosis, and regeneration of hepatocytes. Furthermore, they have been demonstratedto inhibit proliferation of liver cancer cells in vitro, and to be essential for lymphocyte proliferation.In veterinary medicine, the use of BCAAs as integration of a normal dietary plan, is likely to be a validchoice for the same benefit found in human clinical nutrition, although this aspect is still debated.Indeed, long-term oral supplementation with BCAAs in the prevention of liver fibrosis and injury in thedog's liver is still unclear. Aim of the present study will be to determine how BCAAs preserve liverfunctions in vitro. To this purpose we have selected and set up three different in vitro models: hepaticdog cells and canine hepatocellular carcinoma cells plated in 2D monolayer and hepatic dog cellscultured onto 3D scaffolds, obtained from decellularized rabbit liver. All cells adhered and proliferatedonce plated. Cells grown in monolayer quickly entered G0 end arrested growth, ELISA test confirmedtheir ability to produce albumin. Cells grown on scaffold vigorously replicated and showed theircapability to recellularize ECM rabbit liver. These results, although preliminary, demonstrate that theculture conditions used well preserved the original phenotype and function and further support thepossibility to use in vitro models to successfully study BCAA efficacy in dog

    Mobile orbitons in Ca2_2CuO3_3: crucial role of the Hund's exchange

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    We investigate the Cu L3L_3 edge resonant inelastic x-ray scattering (RIXS) spectra of a quasi-1D antiferromagnet Ca2_2CuO3_3. In addition to the magnetic excitations, which are well-described by the two-spinon continuum, we observe two dispersive orbital excitations, the 3dxy3d_{xy} and the 3dyz3d_{yz} orbitons. We carry out a quantitative comparison of the RIXS spectra, obtained with two distinct incident polarizations, with a theoretical model. We show that any realistic spin-orbital model needs to include a finite, but realistic, Hund's exchange JH≈0.5J_H \approx 0.5 eV. Its main effect is an increase in orbiton velocities, so that their theoretically calculated values match those observed experimentally. Even though Hund's exchange also mediates some interaction between spinon and orbiton, the picture of spin-orbit separation remains intact and describes orbiton motion in this compound.Comment: 13 pages, 10 figure

    Isolated slaughterhouse liver as model for normothermic perfusion after warm and cold ischemia: single case report

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    AbstractLiver transplantation is an ultimate procedure in patients suffering end-stage liver diseases. In these last years the donation after cardiac death (DCD) has increased the pool of potential liver donors. Different studies and procedures are involved in the prevention of the main ischemic problems during the reconditioning and resuscitation of the marginal livers. Normothermic extracorporeal liver perfusion (NELP) avoids prolonged cold storage damage that is the main cause of steatosis and biliary tract ischemia in transplanted patiens. Different porcine models have been studied and developed to understand the ischemia mechanism and to select the better technique for NELP.We conducted our study using a DCD pig liver model collected from slaughterhouse. Using extracorporeal membrane oxygenation, 2000 ml of total fluid containing autologous blood, lidocaine, heparin, antibiotics, glucose 10 % solution and flunixin, the NELP was achieved. The liver was perfused over 7 hours after 48 hours of cold storage (4C°), using Eurocollins solution. During the liver withdrawal in the slaughterhouse 20 minutes were waited to simulate the warm ischemia (WI) time. Histological samples, swab for bacterial grow, blood sample, temperature and pulse oximetry saturation were collected to assess the liver viability and function. These analyses revealed stable metabolism throughout perfusion identifying a cycles 2 hours length, coinciding with recovery of oxygen uptake rates to fresh liver, as described in literature.In summary the preliminary established model of isolated hemoperfused slatherhouse liver reveals the important role of the relation between cold storage and normothermic perfusion. Moreover this preliminary study justifies further investigation of the optimization of the treatment protocols and perfusion media

    Structural, Electronic and Magnetic Properties of a Few Nanometer-Thick Superconducting NdBa₂Cu₃O₇ Films

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    Abstract: Epitaxial films of high critical temperature (Tc) cuprate superconductors preserve their transport properties even when their thickness is reduced to a few nanometers. However, when approaching the single crystalline unit cell (u.c.) of thickness, Tc decreases and eventually, superconductivity is lost. Strain originating from the mismatch with the substrate, electronic reconstruction at the interface and alteration of the chemical composition and of doping can be the cause of such changes. Here, we use resonant inelastic x-ray scattering at the Cu L3 edge to study the crystal field and spin excitations of NdBa2Cu3O7x ultrathin films grown on SrTiO3, comparing 1, 2 and 80 u.c.-thick samples. We find that even at extremely low thicknesses, the strength of the in-plane superexchange interaction is mostly preserved, with just a slight decrease in the 1 u.c. with respect to the 80 u.c.-thick sample. We also observe spectroscopic signatures for a decrease of the hole-doping at low thickness, consistent with the expansion of the c-axis lattice parameter and oxygen deficiency in the chains of the first unit cell, determined by high-resolution transmission microscopy and x-ray diffraction

    Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds

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    Thanks to high resolution and polarization analysis, resonant inelastic x-ray scattering (RIXS) magnetic spectra of La2CuO4, Sr2CuO2Cl2 and CaCuO2 reveal a rich set of properties of the spin 1/2 antiferromagnetic square lattice of cuprates. The leading single-magnon peak energy dispersion is in excellent agreement with the corresponding inelastic neutron scattering measurements. However, the RIXS data unveil an asymmetric lineshape possibly due to odd higher order terms. Moreover, a sharp bimagnon feature emerges from the continuum at (1/2,0), coincident in energy with the bimagnon peak detected in optical spectroscopy. These findings show that the inherently complex spin spectra of cuprates, an exquisite manifestation of quantum magnetism, can be effectively explored by exploiting the richness of RIXS cross sections.Comment: 7 pages, 3 figure

    High Tc superconductivity in superlattices of insulating oxides

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    We report the occurrence of superconductivity, with maximum Tc = 40 K, in superlattices (SLs) based on two insulating oxides, namely CaCuO2 and SrTiO3. In these (CaCuO2)n/(SrTiO3)m SLs, the CuO2 planes belong only to CaCuO2 block, which is an antiferromagnetic insulator. Superconductivity, confined within few unit cells at the CaCuO2/SrTiO3 interface, shows up only when the SLs are grown in a highly oxidizing atmosphere, because of extra oxygen ions entering at the interfaces. Evidence is reported that the hole doping of the CuO2 planes is obtained by charge transfer from the interface layers, which act as charge reservoir.Comment: 18 pages, 8 figure
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