Combinatorial approach for improving the outcome of angiogenic therapy in ischemic tissues.

Two major populations of endothelial progenitor cells (EPC), namely endothelial colony forming cells (ECFC, or late outgrowth EPC) and circulating angiogenic cells (CAC, or early outgrowth EPC) have been reported to play important roles in vasculogenesis in numerous pathological conditions. However, the poor retention of cells into the ischemic tissue and neovessel fragility are two major flaws that need to be overcome for successful angiogenic therapy. The objective of this study was to explore and exploit the functional properties of EPC populations in order to increase the effectiveness of post-ischemic cell therapy. The results indicate different, still complementary, effects of the two EPC populations on adherence and proliferation of vascular endothelial cells. Matrigel plug assay and mouse hind limb ischemia model showed that concomitant administration of CAC-secreted factors and ECFC resulted in three-fold increase in local cell retention and improved muscle perfusion, vessel maturation and hind limb regeneration, in comparison to either treatment alone. By concluding, factors secreted by CAC co-administered at the time of ECFC transplantation improve tissue regeneration and vascular repair through stabilization of newly-derived blood vessels.

Characterization of microcapsules: recommended methods based on round-robin testing.

Alginate beads, as well as microcapsules based on alginate, cellulose sulphate and polymethylene-co-guanidine, were produced at diameters of 0.4, 1.0 and 1.5 mm. These standard materials were tested, by independent laboratories, in regards to water activity, bead or capsule size, mechanical resistance and transport behaviour. The water activity and mechanical resistance were observed to increase with bead and capsule size. Transport properties (ingress) were assessed using a variety of low molar mass and macromolecular probes. It was observed that the penetration of Vitamin B12 increased with bead diameter, as did dextran penetration. However, for the membrane-containing microcapsules, larger membrane thickness, observed for the larger capsules, retarded ingress. The authors, who are part of a European working group, recommend that permeability be assessed either using a large range of probes or a broad molar mass standard, with measurements at one or two molar masses insufficient to simulate the behaviour in application. Mechanical compression is seen as a good means to estimate elasticity and rupture of beads and capsules, with the sensitivity of the force transducer, which can vary from microN to tens of N, required to be tuned to the anticipated bead or capsule strength. Overall, with the exception of the mechanical properties, the precision in the inter-laboratory testing was good. Furthermore, the various methods of assessing transport properties agreed, in ranking, for the beads and capsules characterized, with gels having smaller radii being less permeable. For microcapsules, the permeation across the membrane dominates the ingress, and thicker membranes have lower permeability.

Polyvinylamine hydrochloride-based microcapsules: polymer synthesis, permeability and mechanical properties.

Mechanically stable microcapsules, with sizes of 0.4-1.5 mm, have been produced with permeabilities appropriate for applications involving living cells and controlled delivery. Polyvinylamine hydrochloride was employed alone, in miXtures with poly(methylene-co-guanidine) hydrochloride, or as a coating material for pre-formed capsules. The influence of polymer molar mass, the ratio between the two polycations, the coating time, and the capsule size on the properties of the capsules were analysed. The competitive displacement of one polycation with another in the polysaccharide matrix was also documented. The properties of the capsules vary remarkably, depending of the polyelectrolyte combinations used for their preparation. Specifically, capsules could withstand compressive loads of between 0.09-1.67 N, while the permeability varied from 10-120 kDa. Both are within the ranges required for clinical immunosuppressive therapies.

[A study of the microelements in the dental plaque]. / Studiul microelementelor din placa dentara.

In a total of 49 patients, of which 7 were controls, and the other had chronic superficial parodonthopathies, deep chronic mixed parodontopathies and gingivitis, a quantitative analysis was done of microelements from the dental plaque. Neutron activation analysis, chemical and chromatographic methods were used for evidencing the presence of Fe, Mn, Zn, Mg, Co, Ca, Na, and K ions in the dental plaque. Significant changes were noted with regard to the Fe, Zn, and Ca contents of the dental plaque in patients with deep and mixed parodonthopathies. In the patients with gingivitis high Mn and Na concentrations were found and low Mg and K ion contents. Cobalt in the dental plaque was within normal limits in all the patients. Changes of the microelements in the dental plaque are useful for clinical laboratories in view of detecting at an early stage the development of pathological processes which occur in the buccal cavity.

[Unusual aspects of a case of rhinophyma]. / Aspecte inedite ale unui caz de rinofima.

The present paper reports on a case of rhinophyma associated with pendulous fibroma, operated in the same surgical sequence, with grafting the decortication surface of the pyramid with graft of free skin taken from the arm. The clinical and histological characteristics of the case presented and the conclusions to be drawn from it are outlined, as the disease is a nosologic entity rarely met.