Mycobacterium tuberculosis mutT1 (Rv2985) and ADPRase (Rv1700) proteins constitute a two-stage mechanism of 8-Oxo-dGTP and 8-Oxo-GTP detoxification and adenosine to cytidine mutation avoidance

Approximately one third of the world population is infected with Mycobacterium tuberculosis, the causative agent of tuberculosis. A better understanding of the pathogen biology is crucial to develop new tools/strategies to tackle its spread and treatment. In the host macrophages, the pathogen is exposed to reactive oxygen species, known to damage dGTP and GTP to 8-oxo-dGTP and 8-oxo-GTP, respectively. Incorporation of the damaged nucleotides in nucleic acids is detrimental to organisms. MutT proteins, belonging to a class of Nudix hydrolases, hydrolyze 8-oxo-G nucleoside triphosphates/diphosphates to the corresponding nucleoside monophosphates and sanitize the nucleotide pool. Mycobacteria possess several MutT proteins. However, a functional homolog of Escherichia coli MutT has not been identified. Here, we characterized MtuMutT1 and Rv1700 proteins of M. tuberculosis. Unlike other MutT proteins, MtuMutT1 converts 8-oxo-dGTP to 8-oxo-dGDP, and 8-oxo-GTP to 8-oxo-GDP. Rv1700 then converts them to the corresponding nucleoside monophosphates. This observation suggests the presence of a two-stage mechanism of 8-oxo-dGTP/8-oxo-GTP detoxification in mycobacteria. MtuMutT1 converts 8-oxo-dGTP to 8-oxo-dGDP with a K-m of similar to 50 mu M and V-max of similar to 0.9 pmol/min per ng of protein, and Rv1700 converts 8-oxo-dGDP to 8-oxo-dGMP with a K-m of similar to 9.5 mu M and V-max of similar to 0.04 pmol/min per ng of protein. Together, MtuMutT1 and Rv1700 offer maximal rescue to E. coli for its MutT deficiency by decreasing A to C mutations (a hallmark of MutT deficiency). We suggest that the concerted action of MtuMutT1 and Rv1700 plays a crucial role in survival of bacteria against oxidative stress.

A Note on Risk Acceptance, Bankruptcy Avoidance and Riskiness Measures

In this work we clarify the relationships between riskiness, risk acceptance and bankruptcy avoidance. We distinguish between the restriction on the current wealth required to make a gamble acceptable to the decision maker and the restriction on the current wealth required to guarantee no bankruptcy if a gamble is accepted. We focus on the measure of riskiness proposed by Foster and Hart.

Marketing experiencial aplicado a los establecimientos comerciales: Shopping experience

El presente trabajo expone el marco en el que cabe el desarrollo de las decisiones de Marketing en el comercio detallista actualmente, considerando los cambios en el comportamiento y hábitos de compra del cliente, condicionados por los avances tecnológicos y la crisis económica, entre otros. Se analizan algunos de los diferentes factores que deben ser gestionados para la creación de experiencias, y donde el marketing sensorial será protagonista, así como la necesidad de orientar las políticas hacia un comprador que aun siendo sensible al precio, cada vez valora más el factor emocional. Se profundiza en la gestión de la experiencia de compra, y en los factores que han de tenerse en cuenta para realizarla de forma eficiente. Finalmente, se estudia un caso exitoso de marketing experiencial donde puede observarse el uso de las variables analizadas previamente.

Marketing experiencial: El caso de la empresa Flow.

El objetivo fundamental de este estudio se basa en el análisis de una nueva tendencia que incorpora un enfoque diferente a la disciplina del marketing. Hablamos de marketing experiencial, un concepto innovador en el que los clientes se convierten en principales protagonistas. Se trata de conocer tanto las implicaciones como los beneficios que esta práctica supone en el entorno empresarial actual. El concepto del marketing de hoy en día va más allá de la simple combinación de variables tales como publicidad y precio, ya que vemos cómo las experiencias que el cliente percibe pueden afectar su comportamiento de compra de una forma más relevante. Experiencias y, al fin y al cabo, vivencias, sensaciones y emociones pasan a ser punto de partida en la economía actual.

Marketing experiencial aplicado a los establecimientos comerciales: Shopping experience

En el presente trabajo, se analiza el concepto de Marketing experiencial, aplicado a los establecimientos comerciales, lo que denominamos como Shopping Experience. Para ello, en primer lugar se explica el término teórico de Shopping Experience. A continuación se analiza el comportamiento del consumidor a lo largo de los últimos años, cómo han ido cambiando nuestros hábitos de compra y qué es lo que hacen los establecimientos comerciales para adaptarse a estas nuevas exigencias de los consumidores. Veremos nuevos modelos de establecimientos comerciales, donde se ofrece al cliente una experiencia memorable de compra y lo contrastaremos con ejemplos reales. Contamos con el testimonio de un ex – trabajador de Purificación García, donde hace una comparativa con la tienda de Carolina Herrera, y nos explica cuáles son las diferencias más significativas entre ambas, cómo son los diseños de las tiendas y qué papel juegan los sentidos a la hora de generar una experiencia de compra memorable. Finalmente veremos cómo los establecimientos comerciales pueden medir el impacto de estas experiencias en sus clientes y tras realizar un análisis teórico – práctico, se exponen las conclusiones del presente trabajo. Idioma: Castellano

Is inbreeding avoidance driving female mate choice in Verreaux's sifaka lemurs?

Females of different species might exert female mate choice for different reasons, one of them the aim of avoiding inbreeding. In this study I examine the implication of inbreeding avoidance as a mechanism driving female mate choice in Verreaux’s sifaka lemurs (Propithecus verreauxi). In fact, in this species females are dominant and appear to be able to choose certain males to mate with, while observations indicate that rank, body size, canine size and proportions of fights won are not factors influencing female mate choice. So I hypothesized that females mate choice is driven by inbreeding avoidance in Verreaux’s sifaka lemurs. Tissue and fecal samples were collected in the Kirindy Mitea National Park in western Madagascar as a source of DNA. Parentage was assigned for a sample of the population and relatedness coefficients between dams and sires were estimated and compared to those of between random female and male pairs, dams and other candidate sires within the population and within the groups were the offspring were conceived. I found that there were no significant differences in none of the comparisons which means that Verreaux’s sifaka females do not mate more with males that are more distantly related to them. I concluded that inbreeding avoidance does not appear to be the main force driving female mate choice in Verreaux’s sifaka lemurs and I addressed explanations for these findings. With this study I contribute to our knowledge of female mate choice in lemurs.

Marketing Experiencial en el sector de la gastronomía

El presente trabajo expone la adaptación del marketing experiencial al sector de la gastronomía. Veremos que el marketing ha sufrido una evolución, donde ya no es suficiente con satisfacer al cliente, sino que para diferenciarse es necesaria la búsqueda de cómo emocionarle, a través de experiencias únicas y memorables. Se explican los autores más relevantes de esta nueva tendencia denominada marketing experiencial, además del marketing sensorial, que alude a los estímulos generados por cada uno de los cinco sentidos. Se profundiza en el mundo gastronómico, en el cual cada vez se innova más, y en el que los chefs, abren las puertas de sus establecimientos, para ofrecer recuerdos inolvidables mediante una cocina creativa. Finalmente, se estudiarán cuatro restaurantes exitosos, en los cuales se aplica este tipo de marketing.

Avoidance of common problems on ponds and lakes.

This report looks at the events that results in fish deaths on ponds and lakes, and how to control and avoid them. Problems include de-oxygenation of the water, algal growth, water temperature, excessive fish stocks, excessive weed growth and excessive zooplankton

Effect of paradoxical sleep deprivation and stress on passive avoidance behavior

Previous studies have shown that several types of stress can induce memory impairment. However, the memory effects of paradoxical sleep deprivation (PSD), a stressor in itself, are unclear. We therefore compared passive avoidance behavior of rats undergoing PSD and PSD stress yoked-control (PSC) using the "reversed flowerpot method." When rats were kept isolated on a PSC platform for 24 It immediately after criterion training, retention trials showed impaired aversive memory storage. When delayed for 24 h after criterion training, PSC stress did not disrupt retention performance. In rats subjected to PSD, either immediately or 24 It after criterion training, there was no disruption of aversive memory consolidation. These results suggest that, during stress, paradoxical sleep plays a role in erasing aversive memory traces, in line with the theory that we "dream in order to forget." (C) 2003 Elsevier Inc. All rights reserved.

Ketamine affects memory consolidation: Differential effects in T-maze and passive avoidance paradigms in mice

The effects of ketamine, an N-methyl-D-aspartate (NMDA) antagonist, on memory in animals have been limited to the sub-anesthetic dose given prior to training in previous studies. We evaluated the effects of post-training anesthetic doses of ketamine to se

Effects of Prenatal Exposure to a 50-Hz Magnetic Field on One-Trial Passive Avoidance Learning in 1-Day-Old Chicks

We investigated memory impairment in newly hatched chicks following in ovo exposure to a 50-Hz magnetic field (MF) of 2 mT (60 min/day) on embryonic days 12-18. Isolated and paired chicks were used to test the effect of stress during training, and memory retention was tested at 10, 30, and 120 min, following exposure to a bitter-tasting bead (100% methylanthranilate). Results showed that memory was intact at 10 min in both isolated and paired chicks with or without MF exposure. However, while isolated chicks had good memory retention levels at 30 and 120 min, those exposed to MF did not. The results suggest a potential disruption of memory formation following in ovo exposure to MF, with this effect only evident in the more stressed, isolated chicks. Bioelectromagnetics 31:150-155, 2010. (C) 2009 Wiley-Liss. Inc.

Reversible disconnection of the hippocampal-prelimbic cortical circuit impairs spatial learning but not passive avoidance learning in rats

Wistar rats, treated with the GABA(A) receptor agonist muscimol, were used to investigate the role of the hippocampal-prelimbic cortical (Hip-PLC) circuit in spatial learning in the Morris water maze task, and in passive avoidance learning in the step-thr