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Background Acute kidney injury (AKI) induced by renal ischemia/reperfusion (IR) is associated with enhanced production of reactive oxygen species in renal tissues. D-005, a lipid extract obtained from Acrocomia crispa fruit, has previously shown antioxidant effects. The aim of this work was to evaluate the effects of D-005 on renal IR-induced AKI in rats. Methods Rats were randomized into seven groups including a negative control group (vehicle) without AKI and six groups with renal IR-induced AKI as follows: a positive control (vehicle); D-005 treatment at 25, 100, 200, or 400 mg/kg; and dexamethasone at 3 mg/kg. All treatments were orally administered as single doses 1 hour before AKI induction. Biomarkers (serum creatinine, urea, and uric acid concentrations), oxidative variables, and histopathological AKI changes were evaluated in blood and kidney tissues. Results All D-005 doses protected against IR-induced AKI in rats by significantly decreasing biomarkers and histopathological AKI changes as assessed by reduced serum concentrations of creatinine, urea, and uric acid. In addition, all D-005 doses decreased tubular damage, as shown by fewer detached cells and casts in the tubular lumen. D-005 reversed oxidation disturbance markers by decreasing malondialdehyde and sulfhydryl group concentrations in plasma and in kidney homogenates and by increasing kidney catalase activity. Dexamethasone, the reference substance, protected against IR-induced AKI in rats by reducing biochemical and histological variables of renal damage in a similar manner. Conclusion Administration of single oral doses of D-005 markedly and significantly protected against renal IR-induced AKI, possibly due to its known antioxidant effects.

We show that the phase space of three-dimensional gravity contains two layers of dualities: between diffeomorphisms and a notion of "dual diffeomorphisms" on the one hand, and between first order curvature and torsion on the other hand. This is most elegantly revealed and understood when studying the most general Lorentz-invariant first order theory in connection and triad variables, described by the so-called Mielke-Baekler Lagrangian. By analyzing the quasi-local symmetries of this theory in the covariant phase space formalism, we show that in each sector of the torsion/curvature duality there exists a well-defined notion of dual diffeomorphism, which furthermore follows uniquely from the Sugawara construction. Together with the usual diffeomorphisms, these duals form at finite distance, without any boundary conditions, and for any sign of the cosmological constant, a centreless double Virasoro algebra which in the flat case reduces to the BMS$_3$ algebra. These algebras can then be centrally-extended via the twisted Sugawara construction. This shows that the celebrated results about asymptotic symmetry algebras are actually generic features of three-dimensional gravity at any finite distance. They are however only revealed when working in first order connection and triad variables, and a priori inaccessible from Chern-Simons theory. As a bonus, we study the second order equations of motion of the Mielke-Baekler model, as well as the on-shell Lagrangian. This reveals the duality between Riemannian metric and teleparallel gravity, and a new candidate theory for three-dimensional massive gravity which we call teleparallel topologically massive gravity., 41+25 pages; v2: appendix D on Kosmann derivative and symplectic symmetries added, references added

In this paper we show how to translate into tensorial language the Chern-Weil theorem for the Lorentz symmetry, which equates the difference of the Euler densities of two manifolds to the exterior derivative of a transgression form. For doing so we need to introduce an auxiliary, hybrid, manifold whose geometry we construct explicitely. This allows us to find the vector density, constructed out of spacetime quantities only, whose divergence is the exterior derivative of the transgression form. As a consequence we can show how the Einstein-Hilbert, Gauss-Bonnet and, in general, the Euler scalar densities can be written as the divergences of genuine vector densities in the critical dimensions $D=2,4$, etc. As Lovelock gravity is a dimensional continuation of Euler densities, these results are of relevance for Gauss-Bonnet and, in general, Lovelock gravity. Indeed, these vectors which can be called generalized Katz vectors ensure, in particular, a well-posed Dirichlet variational principle., 15 pages

We study a three-dimensional Chern-Simons gravity theory based on the Maxwell algebra. We find that the boundary dynamics is described by an enlargement and deformation of the $\mathfrak{bms}_3$ algebra with three independent central charges. This symmetry arises from a gravity action invariant under the local Maxwell group and is characterized by presence of Abelian generators which modify the commutation relations of the super-translations in the standard $\mathfrak{bms}_3$ algebra. Our analysis is based on the charge algebra of the theory in the BMS gauge, which includes the known solutions of standard asymptotically flat case. The field content of the theory is different than the one of General Relativity, but it includes all its geometries as particular solutions. In this line, we also study the stationary solutions of the theory in ADM form and we show that the vacuum energy and the vacuum angular momentum of the stationary configuration are influenced by the presence of the gravitational Maxwell field., Comment: v3, 23 pages, introduction extended, minor correction, references added, Published version

The S-expansion method is a generalization of the In\"{o}n\"{u}-Wigner (IW) contraction that allows to study new non-trivial relations between different Lie algebras. Basically, this method combines a Lie algebra $\mathcal{G}$ with a finite abelian semigroup $S$ in such a way that a new S-expanded algebra $\mathcal{G}_{S}$ can be defined. When the semigroup has a zero-element and/or a specific decomposition, which is said to be resonant with the subspace structure of the original algebra, then it is possible to extract smaller algebras from $\mathcal{G}_{S}$ which have interesting properties. Here we give a brief description of the S-expansion, its applications and the main motivations that lead us to elaborate a Java library, which automatizes this method and allows us to represent and to classify all possible S-expansions of a given Lie algebra., Comment: 7 pages, 1 figure, Talk at ACAT 2017, Seattle, USA, to appear in Proceedings of ACAT 2017

In this article we describe the Java library that we have recently constructed to automatize the S-expansion method, a powerful mathematical technique allowing to relate different Lie algebras. An important input in this procedure is the use of abelian semigroups and thus, we start with a brief review about the classification of non-isomorphic semigroups made in the literature during the last decades, and explain how the lists of non-isomorphic semigroups up to order 6 can be used as inputs in many of the methods of our library. After describing the main features of the classes that compose our library we present a new method called fillTemplate which tuns out to be very useful to answer whether two given algebras can be S-related., Comment: 6 pages, Talk at ACAT 2017, Seattle, USA, to appear in Proceedings of ACAT 2017

El Factor de Transferencia es un agente natural que aumenta la capacidad para combatir las enfermedades y mejorar la calidad de vida, ha sido usado éxitosamente para tratar enfermedades virales, parasitarias, neurológicas, micóticas y autoinmunes y también utilizado en pacientes que no responden a prescripciones convencionales o que desarrollan reacciones de toxicidad severas a estas. Este producto obtenido a partir de células sin inducir (por el virus Sendai) constituye una nueva y muy apropiada formulación teniendo en cuenta el método de obtención. La dosis terapéutica en humanos es de 1 mg/mL y su frecuencia de administración está asociada a la patología del paciente. Por su gran importancia para su uso en humanos, se realizó un ensayo toxicológico (toxicología aguda), para determinar la seguridad del producto. Se utilizaron tres dosis superiores a la terapéutica. Se realizaron observaciones clínicas diarias y determinaciones del peso corporal de forma semanal. Transcurrida la fase experimental (14 d), se realizó el sacrificio de los animales, todo lo cual se llevó a cabo cumpliendo las normas éticas, con análisis macroscópicos y microscópicos de órganos relacionados con el sistema hemolinfopoyético y el hígado. Al comparar los resultados de los grupos tratados con el placebo, no se observaron diferencias significativas en el peso corporal ni se reportaron efectos adversos en los órganos estudiados, lo que permitió concluir que la nueva formulación no resulta tóxica.

Se estudió la respuesta del tejido óseo a implantes de carbonato de calcio aragonito (CCA). Se utilizaron implantes de Hidroxiapatita Coralina (HA) en la misma forma y proceder quirúrgico como biomaterial de control comparativo. Se investigó el efecto de la composición química sobre la capacidad de curación y la velocidad de reabsorción de ambos biomateriales implantados en el fémur de ratas. Los animales fueron sacrificados a los 3, 7, 15, 21 y 60 d y los implantes fueron recuperados para los análisis posteriores. La evaluación se realiz ó mediante técnicas de microscopia óptica, estudios histológicos y radiográficos, análisis químico cuantitativo de calcio y fósforo y espectroscopia IR de Transformada de Fourier (FT-IR). Se encontró que ambos biomateriales fueron bien asimilados y se integraron al tejido óseo circundante. En el caso de la Hidroxiapatita se observó que a los 60 d el defecto óseo fue reparado, pero el biomaterial mantuvo la misma apariencia inicial. Por el contrario, en ese mismo período, el implante de coral (CCA) disminuyó su tamaño y su apariencia resultó más parecida a la del tejido circundante. Los estudios histológicos mostraron la misma capacidad osteogénica en ambos biomateriales en los primeros 7 d de implantados, pero a los 15 d se aprecia una mayor velocidad de sustitución del tejido fibrovascular por hueso en el caso del CCA. La cinética de biodegradación calculada a partir de los análisis químicos (relación Ca/P) y de los espectros IR coincide con las observaciones histológicas y muestra una mayor velocidad de reabsorción de los implantes de carbonato de calcio (CCA). Se encontró que la transformación del CCA produce una fase similar a la del hueso debido a la pérdida paulatina del anión carbonato y la incorporación del fosfato correspondiente. El CCA también presentó una mayor capacidad osteogénica en comparación con la HA. A los 60 d el (42,5 ± 3,2) % del CCA originalmente implantado se transformó en fosfato de calcio y la velocidad de este proceso se incrementó de (0,22 ± 0,08) %/d a los 7 d hasta (0,7 ± 0,1) %/d a los 60 d de implantado. Los implantes de HA no experimentaron cambios en el período analizado (60 d). En conclusión, igual que la hidroxiapatita porosa, el biomaterial de aragonito estimula la proliferación de tejido vivo hacia el interior de los poros, pero con una mayor velocidad de reabsorción y de generación de nuevo hueso. Estos resultados sugieren que la velocidad de reabsorción de este tipo de biomaterial de implante puede ser controlada en dependencia de la relación fosfato/carbonato en su composición química inicial.

The anti-inflammatory effect of microalgae Spirulina was studied in zymosan-induced arthritis in mice. Four days after the intra-articular injection of zymosan (15 mg/ml), Spirulina (100 and 400 mg/kg per-orally) was administered to animals for 8 days. The mice were than killed and β-glucuronidase was measured in the synovial fluid. Each knee joint was totally removed for histopathological studies. Spirulina significantly reduced the levels of β-glucuronidase that had been increased by zymosan. Histopathological and ultrastructural studies showed inhibition of the inflammatory reaction, whereas no destruction of cartilage, well-preserved chondrocytes, and normal rough endoplasmic reticulum and mitochondria were seen. The anti-arthritic effect exerted by Spirulina as shown in this model may be at least partly due to the previously reported anti-inflammatory and antioxidative properties of its constituent, phycocyanin. To our knowledge, this is the first report on the anti-inflammatory effect of Spirulina in an experimental model of arthritis.

We study charged AdS black hole solutions in five-dimensional Chern-Simons supergravity. The minimal supergroup containing such AdSxU(1) configurations is the superunitary group SU(2,2|N). For this model, we find analytic black hole solutions that asymptote to locally AdS spacetime at the boundary. A solution can carry U(1) charge provided the spacetime torsion is non-vanishing. Thus, we analyze the most general configuration consistent with the local AdS isometries in Riemann-Cartan space. The coupling of torsion in the action resembles that of the universal axion of string theory, and it is ultimately due to this field that the theory acquires propagating degrees of freedom. Through a careful analysis of the canonical structure the local degrees of freedom of the theory are identified in the static symmetric sector of phase space., Comment: 45 pages, no figures

El estudio de adhesivos con base cianoacrílica con fines quirúrgicos para uso oftálmico requiere tanto de la evaluación clínica como histológica debido a que la recuperación del tejido puede inducir cicatrices peregnes que solo son apreciables al microscopio. En el presente trabajo se aplicaron ambas metodolog ías a la evaluación de dos adhesivos con base cianoacrílica de producción nacional. El Tisuacryl®, diseñado para uso dérmico y el Gliciacryl, diseñado para uso en cirugía de la córnea, pues no existe ningún producto disponible en el mercado para uso ocular que sea totalmente tolerado. Se midieron los indicadores convencionales para el ensayo de irritación ocular para evaluar la conjuntiva (aparición de edema, eritema o secreción). Se incorporó la evaluación histológica con la cual, se evaluaron la hiperplasia epitelial, inflamación y fibrosis subcorneal para evaluar la cúrnea y el iris. Ambos indicadores se cuantificaron mediante el uso de escalas confeccionadas tipo Draize. Se encontró una respuesta adecuada para el Gliciacryl en la evaluación clínica, pero la inclusión de la histología demostr ó que ninguno de los dos adhesivos era apropiado para esta aplicación debido a que la fibrosis subcorneal fue progresiva para ambos. Su aplicación se ve limitada solo al caso que se sospeche la pérdida del órgano. A diferencia de la norma, se utilizaron los dos ojos de cada animal, lo que permitió ampliar la muestra con el empleo de un mínimo de animales de experimentación y de recursos materiales. El método desarrollado demostró ser sensible para evidenciar los objetivos planteados, ofreció mayor seguridad en la evaluación de los resultados y estimula a buscar nuevas formulaciones que salven la actual barrera. No obstante, se recomienda completar los estudios biológicos crónicos de estos adhesivos antes de continuar evaluando nuevas formulaciones.

In this paper we show that certain three-dimensional isometry algebras, specifically those of type I, II, III and V (according to Bianchi's classification), can be obtained as expansions of the isometries in two dimensions. In particular, we use the so-called S-expansionmethod, which makes use of the finite Abelian semigroups, because it is the most general procedure known until now. Also, it is explicitly shown why it is impossible to obtain the algebras of type IV, VI-IX as expansions from the isometry algebras in two dimensions. All the results are checked with computer programs. This procedure shows that the problem of how to relate, by an expansion, two Lie algebras of different dimensions can be entirely solved. In particular, the procedure can be generalized to higher dimensions, which could be useful for diverse physical applications, as we discuss in our conclusions., We are grateful to Patricio Salgado for many valuable discussions and for establishing the task. IK was supported by Fondecyt (Chile) grants 1040368, 1050512 and by DIUBB grant (UBB, Chile) 102609. NM and FN wish to thank L Andrianopoli, R D'Auria and M Trigiante for their kind hospitality at Dipartimento di Scienza Applicata e Tecnologia (DISAT) of Politecnico di Torino (POLITO), where part of this work was done. NM is grateful to Pontificia Universidad Catolica de Valparaiso (PUCV) for financial support through a Postdoctoral grant and to Fondecyt (Chile) for financial support through grant 3130445. FN wishes to thank CSIC for a JAE-Predoc grant, co-funded by the European Social Fund.

We show that the so-called semi-simple extended Poincare (SSEP) algebra in $D$ dimensions can be obtained from the anti-de~Sitter algebra $\mathfrak{so} \left( D-1,2 \right)$ by means of the $S$-expansion procedure with an appropriate semigroup $S$. A general prescription is given for computing Casimir operators for $S$-expanded algebras, and the method is exemplified for the SSEP algebra. The $S$-expansion method also allows us to extract the corresponding invariant tensor for the SSEP algebra, which is a key ingredient in the construction of a generalized action for Chern--Simons gravity in $2+1$ dimensions.

It is shown that the expansion methods developed in de Azcarraga et al.[Nucl. Phys. B 662, 185 (2003); Class. Quantum Grav. 21, S1375 (2004)]; can be generalized so that they permit to study the expansion of algebras of loops, both when the compact finite-dimensional algebra and the algebra of loops have a decomposition into two subspaces.

By means of a generalization of the Maurer-Cartan expansion method we construct a procedure to obtain expanded higher-order Lie algebras. The expanded higher order Maurer-Cartan equations for the case $\mathcal{G}=V_{0}\oplus V_{1}$ are found. A dual formulation for the S-expansion multialgebra procedure is also considered. The expanded higher order Maurer Cartan equations are recovered from S-expansion formalism by choosing a special semigroup. This dual method could be useful in finding a generalization to the case of a generalized free differential algebra, which may be relevant for physical applications in, e.g., higher-spin gauge theories.

By means of a generalization of the S-expansion method we construct a procedure to obtain expanded higher-order Lie algebras. It is shown that the direct product between an Abelian semigroup S and a higher-order Lie algebra ($\mathcal{G},[,...,])$ is also a higher-order Lie algebra. From this S-expanded Lie algebra are obtained resonant submultialgebras and reduced multialgebras of a resonant submultialgebra.

Several studies suggest that cyclooxygenase-2 contributes to the delayed progression of ischemic brain damage. In this study we examined whether the highly selective cyclooxygenase-2 inhibitor DFU reduces neuronal damage when administered several hours after 5 min of transient forebrain ischemia in gerbils. The extent of ischemic injury was assessed behaviorally by measuring the increases in locomotor activity and by histopathological evaluation of the extent of CA1 hippocampal pyramidal cell injury 7 days after ischemia. DFU treatment (10 mg/kg, p.o.) significantly reduced hippocampal neuronal damage even if the treatment is delayed until 12 h after ischemia. These results suggest that selective cyclooxygenase-2 inhibitors may be a valuable therapeutic strategy for ischemic brain injury.

Cyclooxygenase-2 is involved in the inflammatory component of the ischemic cascade, playing an important role in the delayed progression of the brain damage. The present study evaluated the pharmacological effects of the selective cyclooxygenase-2 inhibitor nimesulide on delayed neuronal death of hippocampal CA1 neurons following transient global cerebral ischemia in gerbils. Administration of therapeutically relevant doses of nimesulide (3, 6 and 12 mg/kg; i.p.) 30 min before ischemia and at 6, 12, 24, 48 and 72 h after ischemia significantly (P

This research was performed in order to determine the potential protective effects of ozonized sunflower oil (OSO) in the injury of rat gastric mucosa induced by absolute ethanol and as well as to elucidate the role of reactive oxygen species (ROS), lipid peroxidation, and some important constituents of antioxidant defense such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in these effects. OSO was administered to rats intragastrically by a cannula and it was applied during four days to animals. The doses of OSO administered daily to each group of rats were 4, 12, and 24 mg/kg, respectively, and one hour after the last treatment, absolute ethanol (1 mL/200 mg body weight) was administered. Our results showed that gastric ulcer index was significantly reduced in rats pretreated with OSO as compared with ethanol-treated controls. However, in rats pretreated with OSO, no significant reduction of TBARS content in gastric mucosa was found as compared to those rats treated with ethanol alone. In contrast, SOD and GSH-Px activities were significantly increased in gastric mucosa of OSO-pretreated rats with respect to those treated with ethanol alone. In summary, our results demonstrate that OSO pretreatment exerts protective effects in ethanol-induced gastric ulcers in rats. Furthermore, these results provide evidence that these protective effects of OSO are mediated at least partially by stimulation of some important antioxidant enzymes such as SOD and GSH-Px, which are scavengers of ROS and therefore prevent gastric injury induced by them.

Haemophilus influenzae type b (Hib) is a Gram-negative bacterium causing diseases such as meningitis, pneumonia, epiglottis, cellulitis, septicemia and arthritis, among others. Hib-caused meningitis / Hib meningitis is a very serious disease with a death rate of more than 50 % throughout the world; therefore obtaining a vaccine against this bacterium is a goal of the highest priority. The present report presents the results of preclinical safety testing of the Quimi-Hib(r) vaccine (synthetic Hib antigen conjugated to tetanus toxoid) adjuvanted with aluminum phosphate. The battery of toxicological tests included acute toxicity (15 days), local tolerance (15 days) and repeated-dose toxicity (30 days), all of them evaluating the therapeutic dose of the vaccine as part of the studied experimental treatments. Three vaccine dose levels and a placebo (excipients plus adjuvant) were examined, administering the vaccine intramuscularly to Sprague Dawley rats of both sexes. After examining the data obtained from the administration of this wide range of doses to Sprague Dawley rats, it was concluded that the synthetic conjugate vaccine Quimi-Hib(r) adjuvanted in aluminum phosphate is not toxic and does not cause systemic adverse effects. No macroscopic alterations were observed in the studied organs, and the evaluation of the inoculation site only detected indurations caused by macrophage granulomas, resulting from the mechanism of action of the adjuvant included in the formulation.