BACKGROUND AND AIMS Many alpine plant species combine clonal and sexual reproduction to minimize the risks of flowering and seed production in high mountain regions. The spatial genetic structure and diversity of these alpine species is strongly affected by different clonal strategies (phalanx or guerrilla) and the proportion of generative and vegetative reproduction. METHODS The clonal struc...

The most commonly reported reason for errors is that a syringe containing a vinca alkaloid is mistaken for a syringe containing an intrathecal medication. Very few medications, including chemotherapeutic agents, can be administered safely into the intrathecal space. Most intrathecal chemotherapy errors involve the accidental injection of vincristine; however, all of the vinca alkaloids (vinblas...

Vinca alkaloids are used extensively in the treatment of childhood acute lymphoblastic leukemia (ALL) and despite their usefulness, drug resistance remains a serious clinical problem. Vinca alkaloids bind to the beta-tubulin subunit of the alpha/beta-tubulin heterodimer and inhibit polymerization of microtubules. Recent studies have implicated altered beta-tubulin isotype expression and mutatio...

In two hamster cell lines that differed 100-fold in their vinblastine sensitivity, dissolution of the mitotic spindle by vinblastine in living cells correlated with cytotoxicity from vinblastine expressed as suppression of colony formation. The effect on the spindle apparatus occurred in 30 sec or less and thus provides a rapid assay for determining the cytotoxic effects of the Vinca alkaloids,...

Naturally occurring vinca alkaloids, vincristine and vinblastine, at micromolar concentrations enhanced the ornithine decarboxylase activity in a dose-response manner in primary cultures of Ehrlich ascites carcinoma cells. After 8 h of culture in the presence or absence of vinblastine, cycloheximide was added to the medium, a 4.5-fold increase in the half-life of the ornithine decarboxylase act...

Vinflunine is a novel Vinca alkaloid presently in Phase I clinical trials. In preclinical studies, it exhibited superior antitumor activity to that of other Vinca alkaloids, including vinorelbine from which it was synthetically derived. Vinca alkaloids appear to inhibit cell proliferation by affecting the dynamics of spindle microtubules. Here we have analyzed the effects of vinflunine and vino...

Vinflunine is a novel Vinca alkaloid presently in Phase I clinical trials. In preclinical studies, it exhibited superior antitumor activity to that of other Vinca alkaloids, including vinorelbine from which it was synthetically derived. Vinca alkaloids appear to inhibit cell proliferation by affecting the dynamics of spindle microtubules. Here we have analyzed the effects of vinflunine and vino...

Variations in the inulin contents have been detected in rhizophores of Vernonia herbacea during the phenological cycle. These variations indicate the occurrence of active inulin synthesis and depolymerization throughout the cycle and a role for this carbohydrate as a reserve compound. 1-Fructan exohydrolase (1-FEH) is the enzyme responsible for inulin depolymerization, and its activity has been...