Obtención de lípidos bioactivos de Pleuroncodes monodon utilizando solventes orgánicos y CO2 supercrítico

A huge volume of Engraulis ringens (Peruvian anchoveta) is caught together with the species Pleuroncodes monodon (munida), whose potential bioactive lipids are not commercially exploited. In the present study, lipid with carotenoid pigment (astaxanthin) and essential fatty acids (EPA+DHA) were obtained from munida lipids extracted with hexane:isopropyl alcohol (He-I), acetone (Ac), ethanol (Et) and supercritical CO2 + ethanol (SC-CO2-Et). The functional quality of the fatty acids was determined by atherogenicity index (AI), thrombogenicity index (TI) and the hypocholesterolemia:hypercholesterolemia (H:H) ratio. The highest astaxanthin (ASTX) contents (4238.65 and 4086.71 µg/g lipid) corresponded to extractions using Ac and SC-CO2-Et. EPA+DHA ranged from 31.15 to 31.85% and the functional quality ranges were between 0.56-0.61 (AI), 0.19-0.21 (TI) and 1.73-1.81 (H:H). Consequently, SC-CO2-Et extraction would be advisable because of its low environmental impact. The IA and IT quality indexes suggest that the consumption of munida lipids would be healthy, although the H:H ratio shows the opposite.RESUMEN Las enormes capturas de Engraulis ringens (anchoveta Peruana) son acompañadas por la especie Pleuroncodes monodon (munida) cuyo potencial en lípidos bioactivos no es aprovechado comercialmente. En el presente estudio se obtuvo lípidos con pigmentos carotenoides (astaxantina) y ácidos grasos esenciales (EPA+DHA) a partir de lípidos de munida extraídos con hexano:alcohol isopropílico (He-I), acetona (Ac), etanol (Et) y CO2 supercrítico + etanol (SC-CO2-Et). La calidad funcional de los ácidos grasos fue evaluada mediante índices de aterogenicidad (AI), trombogenicidad (TI) y la relación hipocolesterolemia:hipercolesterolémica (H:H). Los mayores contenidos de astaxantina (ASTX) (4238.65 y 4086.71 µg/g de lípido) fueron obtenidos utilizando Ac y SC-CO2-Et. En todas las muestras EPA+DHA osciló entre 31.15 y 31.85% y los rangos de índices de calidad funcional fueron: 0.56-0.61 (AI), 0.19-0.21 (TI) y 1.73-1.81 (H:H). Se concluye que la extracción SC-CO2-Et sería recomendable por su bajo impacto al medio ambiente. Los índices de calidad AI y TI sugieren que el consumo de lípido de munida podría ser saludable, aunque la relación H:H muestra lo contrario

Spin-Glass State in CuGa2O4\rm CuGa_2O_4

Magnetic susceptibility, magnetization, specific heat and positive muon spin relaxation (\musr) measurements have been used to characterize the magnetic ground-state of the spinel compound $\rm CuGa_2O_4$. We observe a spin-glass transition of the S=1/2 $\rm Cu^{2+}$ spins below $\rm T_f=2.5K$ characterized by a cusp in the susceptibility curve which suppressed when a magnetic field is applied. We show that the magnetization of $\rm CuGa_2O_4$ depends on the magnetic histo Well below $\rm T_f$, the muon signal resembles the dynamical Kubo-Toyabe expression reflecting that the spin freezing process in $\rm CuGa_2O_4$ results Gaussian distribution of the magnetic moments. By means of Monte-Carlo simulati we obtain the relevant exchange integrals between the $\rm Cu^{2+}$ spins in this compound.Comment: 6 pages, 16 figure

Prevalence of drug resistance and newly recognised treatment-related substitutions in the HIV-1 reverse transcriptase and protease genes from HIV-positive patients naïve for anti-retrovirals

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Maternal anthropometry for prediction of pregnancy outcomes: Memorandum from a USAID/WHO/PAHO/MotherCare meeting

The meeting discussed two main areas concerning maternal anthropometry in developing countries: (1) how various anthropometric indicators can be best utilized for assessing and monitoring the nutritional status of women at different times in their reproductive lives, and (2) the predictive value of various anthropometric indicators for identifying benefit or risk for maternal and perinatal/neonatal health and nutritional outcomes of pregnancy. The indicators discussed were prepregnancy weight, height, weight gain in pregnancy, arm circumference, weight-for-height and body mass index (weight (kg)/height (m)2). Some 50 experts reached consensus on the tools for assessing maternal nutritional status for widespread field application in developing countries, and on priority research needs. This Memorandum summarizes the general recommendations which have important and immediate field applications, as well as priority research issues related to specific indicators

New hadrons as ultra-high energy cosmic rays

Ultra-high energy cosmic ray (UHECR) protons produced by uniformly distributed astrophysical sources contradict the energy spectrum measured by both the AGASA and HiRes experiments, assuming the small scale clustering of UHECR observed by AGASA is caused by point-like sources. In that case, the small number of sources leads to a sharp exponential cutoff at the energy E<10^{20} eV in the UHECR spectrum. New hadrons with mass 1.5-3 GeV can solve this cutoff problem. For the first time we discuss the production of such hadrons in proton collisions with infrared/optical photons in astrophysical sources. This production mechanism, in contrast to proton-proton collisions, requires the acceleration of protons only to energies E<10^{21} eV. The diffuse gamma-ray and neutrino fluxes in this model obey all existing experimental limits. We predict large UHE neutrino fluxes well above the sensitivity of the next generation of high-energy neutrino experiments. As an example we study hadrons containing a light bottom squark. These models can be tested by accelerator experiments, UHECR observatories and neutrino telescopes.Comment: 17 pages, revtex style; v2: shortened, as to appear in PR

Perturbative Effects in the Form Factor \gamma\gamma^*\to \pi and Extraction of the Pion Wave Function from CLEO Data

We study the pion form factor F^{\pi \gamma\gamma^*}(Q^2) in the light-cone sum rule approach, accounting for radiative corrections and higher twist effects. Comparing the results to the CLEO experimental data on F^{\pi \gamma\gamma^*}(Q^2), we extract the the pion distribution amplitude of twist-2. The deviation of the distribution amplitude from the asymptotic one is small and is estimated to be a_2(\mu) = 0.12 \pm 0.03 at \mu=2.4 GeV, in the model with one non-asymptotic term. The ansatz with two non-asymptotic terms gives some region of a_2 and a_4, which is consistent with the asymptotic distribution amplitude, but does not agree with some old models.Comment: 21 pages, LaTeX, 7 eps figures; (v2): Phys. Rev. D versio

Fibroblast Growth Factor 7 Releasing Particles Enhance Islet Engraftment and Improve Metabolic Control Following Islet Transplantation in Mice with Diabetes

open access articleTransplantation of islets in Type 1 diabetes is limited by poor islet engraftment into the liver, with 2-3 donor pancreases required per recipient. We aimed to condition the liver to enhance islet engraftment to improve long-term graft function. Diabetic mice received a non-curative islet transplant (n=400 islets) via the hepatic portal vein (HPV) with Fibroblast Growth Factor 7 loaded galactoslyated poly(DL-lactide-co-glycolic acid) (FGF7-GAL-PLGA) particles; 26μm diameter particles specifically targeted the liver, promoting hepatocyte proliferation in short-term experiments: in mice receiving 0.1mg FGF7-GAL-PLGA particles (60ng FGF7) versus vehicle, cell proliferation was induced specifically in the liver with greater efficacy and specificity than subcutaneous FGF7 (1.25mg/kg ×2 doses; ~75μg FGF7). Numbers of engrafted islets and vascularisation were greater in liver sections of mice receiving islets and FGF7-GAL-PLGA particles versus mice receiving islets alone, 72 hours post-transplant. More mice (6 out of 8) that received islets and FGF7-GAL-PLGA particles normalised blood glucose concentrations by 30- days post-transplantation, versus 0 of 8 mice receiving islets alone with no evidence of increased proliferation of cells within the liver at this stage and normal liver function tests. This work shows liver targeted FGF7-GAL-PLGA particles achieve selective FGF7 delivery to the liver promoting islet engraftment to help normalise blood glucose levels with a good safety profile

Polarized Parton Distributions in the Nucleon

The distribution of the spin of the nucleon among its constituents can be parametrized in the form of polarized parton distribution functions for quarks and gluons. Using all available data on the polarized structure function $g_1(x,Q^2)$, we determine these distributions both at leading and next-to-leading order in perturbation theory. We suggest three different, equally possible scenarios for the polarized gluon distribution, which is found to be only loosely constrained by current experimental data. We examine various possibilities of measuring polarized parton distributions at future experiments.Comment: 18 pages, LATEX, 6 figures available as .uu fil