Some biological effects of a new alkaloid, Vincaleukoblastine (VLB), are described. In mice bearing the t ransplantable leukemias LI~10, P1534, and AKr or Ehrlieh ascites tumor, t rea tment with VLB effectively prolonged survival. The effectiveness of t r ea tment depended on the amount and spacing of dosage and the time of the institution of t rea tment after t ransplantat ion. A single inject...

1 Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America, 2 Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil, 3 Fundação Oswaldo Cruz – Fiocruz, Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Rio de Janeiro, Brazil, 4 Department of Physiology and Biophysi...

The wide range of different effects induced by electric fields in biological macromolecules is clearly due to the unusual quality and quantity of their electric parameters. A general concept for a quantitative description of the polarizability of macromolecules remains to be established. In the case of DNA, experimental data indicate the existence of an effective polarization length N(p); at ch...

Biological materials, such as isolated protein networks, tissues and living cells are extremely heterogeneous and contain structures on length scales from nanometers to hundreds of microns. Their complex geometries and sensitivity to environmental conditions make traditional measurements of structure and mechanics difficult, challenging experimenters to develop new techniques. In this work, we ...

We formally characterize a set of causality-based properties of metabolic networks. This set of properties aims at making precise several notions on the production of metabolites, which are familiar in the biologists’ terminology. From a theoretical point of view, biochemical reactions are abstractly represented as causal implications and the produced metabolites as causal consequences of the i...

We propose an approach to falsification of oscillation properties of parametric biological models, based on the recently developed techniques for testing continuous and hybrid systems. In this approach, an oscillation property can be specified using a hybrid automaton, which is then used to guide the exploration in the state and input spaces to search for the behaviors that do not satisfy the p...

A review of reported tissue optical properties summarizes the wavelength-dependent behavior of scattering and absorption. Formulae are presented for generating the optical properties of a generic tissue with variable amounts of absorbing chromophores (blood, water, melanin, fat, yellow pigments) and a variable balance between small-scale scatterers and large-scale scatterers in the ultrastructu...

This overview is focused on the bilirubin molecule and its important biological properties. For a long time, bilirubin has been considered a waste product of heme catabolism with potential toxic effects especially on the central nervous system. However, bilirubin has attracted the attention of scientists because of its protective effects. Mildly elevated plasma bilirubin levels are associated w...

The demonstration by Hamilton et al. (1948) and Werko et al. (1949) that the analysis of timeconcentration curves of intravenously injected Evans Blue (T-1824) gave estimates of the cardiac output in man that corresponded closely with those obtained by the direct Fick method stimulated a widespread use of the dye method. However, those properties of Evans Blue that led Dawson et al. (1920) to s...

Proteins present in the seminal plasma of mammals are known to influence functions associated with ejaculated spermatozoa such as motility, capacitation, acrosome reaction and fertilising ability. The proteins isolated and characterised so far influence only one of the above functions of spermatozoa. Seminalplasmin, a protein isolated from the seminal plasma of bull is exceptional in that it in...