398 research outputs found
Nutritional composition and antioxidant and cancer chemopreventive activites of fruits of Psdium myrtoides (O. Berg)
Psidium myrtoides fruits food industries produce by-products such as liqueurs, ice cream, jellies, and juices. However, there needs to be more information about the nutritional composition of fruits, as well as the biological potential, mainly of seed flour. Therefore, the present study aimed to evaluate the nutritional composition and antioxidant and cancer chemopreventive activities of pulp and seed of fruits ofPsidium myrtoides. Moisture content, total minerals and mineral profile, total lipids and fatty acids profile, total proteins, dietary fiber (soluble and insoluble) and total carbohydrates were analyzed. Vitamins C and complex B, organic acids and the profile of phenolic compounds were also determined. DPPH and ABTS methods evaluated the antioxidant activity, and cancer chemopreventive activity was evaluated by quinonereductase induction and NF-κB inhibitory activity. The fruits are a good source of thiamine, iron, phosphorus, potassium, fiber, and protein.Linoleic acid was the major fatty acid in both pulp and seed. Quercetin (1600 μg/100g) and pyrogallol (819 μg/100g) were the major phenolic compounds pulp and seed, respectively. The fruits showed strong antioxidant capacity, mainly the seeds, and the ability to induce quinone reductase activity, highlighting a cancer chemopreventive activity. Seed flour has a high potential to enrich food, in addition to valuing agroindustrial by-products, where we can highlight 25%, 13% and 37% of the recommended daily intake for iron (1.6 mg/100g), phosphorus (58 mg/100g) and vitamin B1 (450 μg/100g), respectively, in addition to antioxidant and cancer chemopreventive activities
Caloric restriction is more efficient than physical exercise to protect from cisplatin nephrotoxicity via PPAR-alpha activation
The antineoplastic drug cisplatin promotes renal injury, which limits its use. Protocols that reduce renal cisplatin toxicity will allow higher doses to be used in cisplatin treatment. Here, we compare physical exercise and caloric restriction (CR) as protocols to reduce cisplatin renal injury in mice. Male C57BL/6 were divided into four groups: Control, cisplatin, exercise + cisplatin, and 30% CR + cisplatin. Animals were injected with a single dose of cisplatin (20 mg/kg i.p.) and sacrificed 96 h after injection. Quantitative real time PCR, histological analyses, immunohistochemistry, and biochemical measurements were performed to investigate renal injury, necrosis, apoptosis, and inflammatory mechanisms. Both protocols protected against cisplatin renal injury, but CR was more effective in reducing uraemia and renal necrosis. The CR + Cisplatin group exhibited reduced serum IL-1{beta} and TNF-{alpha} levels. No differences were noted in the renal mRNA expression of cytokines. Both interventions reduced apoptosis, but only the CR + Cisplatin group decreased TNFR2 protein expression. PPAR-{alpha} was activated in mice after CR. An antagonist of PPAR-{alpha} blocked the protective effect of CR. Both interventions attenuated the nephrotoxicity caused by cisplatin injection, but CR + Cisplatin showed a better response by modulating TNFR2. Moreover, part of the CR benefit depends on PPAR-{alpha} activation
Spectral functions of the Falicov-Kimball model with electronic ferroelectricity
We calculate the angular resolved photoemission spectrum of the
Falicov-Kimball model with electronic ferroelectricity where - and
-electrons have different hoppings. In mix-valence regimes, the presence of
strong scattering processes between - excitons and a hole, created by
emission of an electron, leads to the formation of pseudospin polarons and
novel electronic structures with bandwidth scaling with that of -
excitons. Especially, in the two-dimensional case, we find that flat regions
exist near the bottom of the quasiparticle band in a wide range of the - and
-level energy difference.Comment: 5 pages, 5 figure
Quasiparticle Interactions in Fractional Quantum Hall Systems: Justification of Different Hierarchy Schemes
The pseudopotentials describing the interactions of quasiparticles in
fractional quantum Hall (FQH) states are studied. Rules for the identification
of incompressible quantum fluid ground states are found, based upon the form of
the pseudopotentials. States belonging to the Jain sequence nu=n/(1+2pn), where
n and p are integers, appear to be the only incompressible states in the
thermodynamic limit, although other FQH hierarchy states occur for finite size
systems. This explains the success of the composite Fermion picture.Comment: RevTeX, 10 pages, 7 EPS figures, submitted fo Phys.Rev.
Colossal dielectric constants in transition-metal oxides
Many transition-metal oxides show very large ("colossal") magnitudes of the
dielectric constant and thus have immense potential for applications in modern
microelectronics and for the development of new capacitance-based
energy-storage devices. In the present work, we thoroughly discuss the
mechanisms that can lead to colossal values of the dielectric constant,
especially emphasising effects generated by external and internal interfaces,
including electronic phase separation. In addition, we provide a detailed
overview and discussion of the dielectric properties of CaCu3Ti4O12 and related
systems, which is today's most investigated material with colossal dielectric
constant. Also a variety of further transition-metal oxides with large
dielectric constants are treated in detail, among them the system La2-xSrxNiO4
where electronic phase separation may play a role in the generation of a
colossal dielectric constant.Comment: 31 pages, 18 figures, submitted to Eur. Phys. J. for publication in
the Special Topics volume "Cooperative Phenomena in Solids: Metal-Insulator
Transitions and Ordering of Microscopic Degrees of Freedom
Search for the Flavor-Changing Neutral Current Decay with the HERA-B Detector
We report on a search for the flavor-changing neutral current decay using events recorded with a dimuon trigger in
interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find
no evidence for such decays and set a 90% confidence level upper limit on the
branching fraction .Comment: 17 pages, 4 figures (of which 1 double), paper to be submitted to
Physics Letters
Measurement of the J/Psi Production Cross Section in 920 GeV/c Fixed-Target Proton-Nucleus Interactions
The mid-rapidity (dsigma_(pN)/dy at y=0) and total sigma_(pN) production
cross sections of J/Psi mesons are measured in proton-nucleus interactions.
Data collected by the HERA-B experiment in interactions of 920 GeV/c protons
with carbon, titanium and tungsten targets are used for this analysis. The
J/Psi mesons are reconstructed by their decay into lepton pairs. The total
production cross section obtained is sigma_(pN)(J/Psi) = 663 +- 74 +- 46
nb/nucleon. In addition, our result is compared with previous measurements
Magnetization and dimerization profiles of the cut two-leg spin ladder and spin-1 chain
The physical properties of the edge states of the cut two-leg spin ladder are
investigated by means of the bosonization approach. By carefully treating
boundary conditions, we derive the existence of spin-1/2 edge states in the
spin ladder with a ferromagnetic rung exchange and for the open spin-1
Heisenberg chain. In contrast, such states are absent in the antiferromagnetic
rung coupling case. The approach, based on a mapping onto decoupled
semi-infinite off-critical Ising models, allows us to compute several physical
quantities of interest. In particular, we determine the magnetization and
dimerization profiles of the cut two-leg spin ladder and of the open
biquadratic spin-1 chain in the vicinity of the SU(2) WZNW critical point.Comment: RevTeX 4, no figure, 26 page
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