Química y actividad biológica en Huperzia saururus. Chemistry and biological activity in Huperzia saururus.

El presente proyecto apunta a buscar una posible solución a dos problemáticas de salud que afectan a un importante grupo de la población mundial y son los asociados a la enfermedad de Alzheimer (EA) y a la disfunción eréctil. La EA es una enfermedad neurodegenerativa progresiva caracterizada por la pérdida de memoria a corto plazo, entre otras manifestaciones. En la actualidad la terapia más utilizada son los inhibidores de la acetilcolinesterasa (AChE), ya que acetilcolina es el principal neurotransmisor afectado. No obstante, los agentes terapéuticos utilizados presentan efectos no deseados a nivel gastrointestinal, lo que motiva la búsqueda de nuevos agentes. A partir del estudio de la especie autóctona Huperzia saururus aislamos hasta el presente 10 alcaloides, algunos de los cuales resultaron activos sobre la retención de memoria, investigación realizada mediante ensayos tanto in vitro como in vivo. A partir de los promisorios resultados obtenidos se continuarán profundizando estos estudios y también se buscará el farmacóforo, la parte de la estructura responsable de la actividad. Para ello, se realizarán modificaciones químicas de los grupos funcionales y los productos obtenidos serán igualmente evaluados por su actividad sobre memoria. Los que resulten activos serán investigados en relación a su toxicidad, en la búsqueda de potenciales agentes terapéuticos. Paralelamente se estudiarán las diferentes familias de compuestos presentes en la especie, dado que el uso popular proclama su efecto afrodisíaco. La búsqueda de un afrodisíaco perfecto que incremente el deseo sexual, el placer y el desempeño, ha sido una constante desde los tiempos remotos. En todos los casos, se ha buscado mejorar el rendimiento sexual o combatir la disfunción eréctil (DE). Este término se describe como “la incapacidad constante para alcanzar o mantener una erección que es satisfactoria para el rendimiento sexual”. Para investigar la actividad biológica de H. saururus, los extractos y compuestos aislados serán evaluados por la generación de NO que produzcan, la que será estimada mediante la acumulación de nitrito, metabolito estable del NO, en sobrenadantes de cultivo de células endoteliales (HUVEC). Los que resulten efectivos serán evaluados mediante ensayos in vivo tales como, el de conducta sexual en machos y de comportamiento de monta. Del mismo modo que para los alcaloides, se estudiará la toxicidad de los compuestos que resulten activos a los fines de proseguir la metodología en la investigación preclínica de potenciales medicamentos. The present Project aims to look for a possible solution for two health problems that affect an important group of world population and they are those associated to Alzheimer Disease (AD) and Erectile Dysfunction. AD is a neurodegenerative progressive disease characterized by short term memory loss, among other signs. Nowadays the most used therapy are the acethylcholinesterase inhibitors (AChE), in view that the acethylcholine is the main neurotransmitter affected. Nevertheless, the therapeutic agents used present collateral effects at gastrointestinal level, so it motivates the search for new agents. From the autochthonous species Huperzia saururus we have isolated 10 alkaloids until the present, some of which were active on memory retention, investigation developed in vitro and in vivo. After these promising results, these studies will be continued, as well as the search for the pharmacophore. For this reason, chemical modifications on functional groups will be done and the obtained products will be evaluated on their activity on memory as well. In line with this, the different families of compounds present in H. saururus will be studied in view that the popular use claims its aphrodisiac effect. The search for a perfect aphrodisiac that increase the sexual desire, the pleasure and performance was a constant since the old times. In all the cases it was looked a better sexual performance or fight against the erectile dysfunction (DE). For investigate the biological activity of H. saururus, the extracts and the isolated compounds will be evaluated on the NO generation, which will be estimated by means of nitrite accumulation, stable metabolite of NO, in supernatants of endothelial cell cultures (HUVEC). The compounds that appear effectives will be evaluated by in vivo assays such as sexual male behavior, and mount behavior. As for alkaloids, toxicity of active compounds will be studied to follow the pre-clinic methodology research of potential medicines.

Coordination chemistry of acrylamide and N-pyrazolylpropanamide : syntheses and structures

Magdeburg, Univ., Fak. für Verfahrens- und Systemtechnik, Diss., 2006

Journal of Natural Philosophy, Chemistry & the Arts.

v. 2 (1799)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 5 (1802)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 28 (1811)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 9 (1804)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 3 (1800)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 15 (1806)

Journal of Natural Philosophy, Chemistry & the Arts.

v. 4 (1801)

Multimarket contact in pharmaceutical markets

The purpose of this paper is to analyze the effect of multimarket contact on the behavior of pharmaceutical firms controlling for different levels of regulatory constraints using IMS MIDAS database. Theoretically, firms that meet in several markets are expected to be capable of sustaining implicitly more profitable out- comes, even if perfect monitoring is not possible. Firms may find it profitable to redistribute their market power among markets where they are operating. We present evidence for nine OECD countries with different degrees of regulation and show that regulation affects the importance of economic forces on firms' price setting behavior. Furthermore, our results confirms the presence of the predictions of the multimarket theory for more market friendly countries (U.S. and Canada) and less regulated ones (U.K., Germany, Netherlands), in contrast, for highly regulated countries (Japan, France, Italy and Spain) the results are less clear with some countries being

Anti-doping testing at the 2008 European football championship.

Big sports events like the 2008 European Football Championship are a challenge for anti-doping activities, particularly when the sports event is hosted by two different countries and there are two laboratories accredited by the World Anti-Doping Agency. This challenges the logistics of sample collection as well as the chemical analyses, which must be carried out timeously. The following paper discusses the handling of whereabouts information for each athlete and the therapeutic use exemption system, experiences in sample collection and transportation of blood and urine samples, and the results of the chemical analysis in two different accredited laboratories. An overview of the analytical results of blood profiling and growth hormone testing in comparison with the distribution of the normal population is also presented.