Cause of withering of staghorn sumach [Rhus typhina L.] in selected localities in Slovakia

Health state of Rhus typhina was evaluated in 59 localities and 74 sites over the years 2001-2003 with scope (1) to identify the parasitic mycoflora of R. typhina in Slovakia and (2) to identify the occurrence of Cryphonectria parasitica, declared as an quarantine pest by the EPPO, besides the chestnut (Castanea sativa Mill.) and oak (Quercus sp.) also on R. typhina. The fungus Botryosphaeria ribis (Gross.) Dugg. (pycnidial state Dothiorella mali (Ell.) Ev) caused damage to the R. typhina. Damage to R. typhina caused by B. ribis was only recorded in 15 localities. Mean growth rate of hyphae of the fungus ranged from 25.7 to 48.3 mm after 96 hours of cultivation. The most appropriate medium for cultivation was 3% potato dextrose agar. The occurrence of the fungus Fusarium oxysporum Schlecht and mainly of quarantine fungus C. parasitica has not been recorded in the evaluated sites

Population structure of Cryphonectria parasitica in the Modry Kamen region

The European chestnut was evaluated for Chestnut blight disease in the Modrý Kameň region, in 2010. A total of 1321 trees and sprouts were selected. There were 140 healthy trees, without any symptoms of Cryphonectria parasitica infection. Nearly 90% of the evaluated trees and sprouts were diseased. The health condition index (IHC) on 11 experimental plots varied from 2.31 to 4.03. Every collected sample was identified as having C. parasitica. All isolates had the orange culture morphology; all isolates were virulent. Among the isolates, 8 vc types were detected. Vc type EU-2 was dominant, it comprised 37.14% of the tested isolates. Two other vc types: EU 1 and EU 12 were frequently detected

Positive impact of dynamic seeding of mesenchymal stem cells on bone-like biodegradable scaffolds with increased content of calcium phosphate nanoparticles

One of the main aims of bone tissue engineering, regenerative medicine and cell therapy is development of an optimal artificial environment (scaffold) that can trigger a favorable response within the host tissue, it is well colonized by resident cells of organism and ideally, it can be in vitro pre-colonized by cells of interest to intensify the process of tissue regeneration. The aim of this study was to develop an effective tool for regenerative medicine, which combines the optimal bone-like scaffold and colonization technique suitable for cell application. Accordingly, this study includes material (physical, chemical and structural) and in vitro biological evaluation of scaffolds prior to in vivo study. Thus, porosity, permeability or elasticity of two types of bone-like scaffolds differing in the ratio of collagen type I and natural calcium phosphate nanoparticles (bCaP) were determined, then analyzes of scaffold interaction with mesenchymal stem cells (MSCs) were performed. Simultaneously, dynamic seeding using a perfusion bioreactor followed by static cultivation was compared with standard static cultivation for the whole period of cultivation. In summary, cell colonization ability was estimated by determination of cell distribution within the scaffold (number, depth and homogeneity), matrix metalloproteinase activity and gene expression analysis of signaling molecules and differentiation markers. Results showed, the used dynamic colonization technique together with the newly-developed collagen-based scaffold with high content of bCaP to be an effective combined tool for producing bone grafts for bone implantology and regenerative medicine