Novel Vanadium-Loaded Ordered Collagen Scaffold Promotes Osteochondral Differentiation of Bone Marrow Progenitor Cells.

Bone and cartilage regeneration can be improved by designing a functionalized biomaterial that includes bioactive drugs in a biocompatible and biodegradable scaffold. Based on our previous studies, we designed a vanadium-loaded collagen scaffold for osteochondral tissue engineering. Collagen-vanadium loaded scaffolds were characterized by SEM, FTIR, and permeability studies.

Ordered collagen membranes: production and characterization.

A collagen membrane with microscopic order is presented. The membranes were produced with acid-soluble collagen, using two different methods to obtain orientation. The product was characterized by mean of UV and IR spectra, scanning electronic microscopy, optical microscopy and laser diffractometry.

Evoked potentials in the rabbit visual cortex reflect changes in line orientation and intensity.

Changes in the amplitudes of evoked potentials in the visual cortex of conscious rabbits in response to substitution of flashing lines of different orientations (0-90 degrees ) but constant intensity were studied, along with interneurons of different intensities but constant orientation, and complex stimuli with simultaneous changes in flash orientation and intensity. Factor analysis of the results showed that analysis of the N85 peak of evoked potentials produced by substitution of stimuli with different orientations but constant intensity identified a two-dimensional sensory space for orientations. An achromatic sensory space was also detected using substitution of lines of different intensities but constant orientation.

[Visual evoked potentials in rabbit's visual cortex reflect variations in orientation and intensity of lines].

Amplitude variations of visual evoked potentials (VEP) in rabbit were studied using changes of three types of stimuli: lines with different orientations (0-90 degree) but constant in intensity, lines with different intensities but constant in orientation, and complex stimuli with different intensities and different orientations. Factor analysis of component N85 of VEP to stimuli with varying orientation and constant intensity revealed two-dimensional sensorial space of orientations. Also, the two-dimensional achromatic sensorial space was revealed for stimuli different only in intensities.

[Electrodynamics of interactions in electrolyte solutions and their biological significance].

Attention is drawn to the fact that the interaction of charges in aqueous solutions of electrolytes, such as media having physiological characteristics, depends not only on the distance between interacting charges but also on the frequency that determines their dynamics. This fact has significant consequences for some biological processes and their kinetics. The analysis of reasons for charge shielding, including the dynamic effects, shows that, even at distances exceeding the Debye length, electric interactions in systems similar to physiological are effective provided that charges move with frequencies higher than 250 MHz.