In-vivo evaluation of the “hia-vad” : a new German ventricular assist device

Helmholtz Ventricular Assist Devices (VAD) are pneumatically driven polyurethane membrane pumps with various volumes. The pumps are placed paracorporeally and connected with commercially available cannulas between the left atrium and aorta (left ventricular assist device) and/or right atrium and pulmonary artery (right ventricular assist device, bi-ventricular assist device). The pumps can be driven with a stand-alone driving system or with a Helmholtz IABP-console interface. Seventeen animal experiments (on calves) with Helmholtz VAD's were performed to evaluate experimental protocols, to optimize surgical techniques, and to improve design and manufacturing techniques. Blood chemistry and cell counts demonstrated that the tested HIA-70 produces low mechanical blood damage. In the course of the animal experiments the Helmholtz VAD's were made totally transparent, whereby they became easy to de-air, efficient, and affordable

Potent nor-triterpenoid blockers of the voltage-gated potassium channel Kv1.3 from Spachea correae

The isolation and structure elucidation of two novel nor-triterpenoid KV1.3 potassium channel blockers correolide and dehydrocorreolide from the Costa Rican tree Spachea correae are reported. The first potent and selective small molecule blockers of KV 1.3, cprreolide (1) and its dehydro derivative 2 have been identified from extracts of Spachea correoe. Agents that inhibit the opening of this voltage-gated potassium channel can be expected to have immunosuppressive properties.Instituto Nacional de Biodiversidad//INBio/Costa RicaUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Químic