Strain improvement of Claviceps purpurea by protoplast fusion without introducing auxotrophic markers

Protoplasts of morphologically and biochemically different Claviceps purpurea strains producing ergotoxins were fused without introducing selective auxotrophic markers. Fused strains thus obtained differed significantly in biosynthetic activity and morphology from the prototrophic isolates obtained after fusion of the same parent strains marked by auxotrophy. Comparison of the two types of fused strains showed about tenfold higher alkaloid production in fusants obtained from prototrophic strains. Selected stable prototrophic isolates also showed a significant productivity improvement in comparison with the original parent strains. Correspondence to: M. Didek-Brumec     

Epidemiology of dermatomycosis in the eastern Croatia--today and yesterday

The aim of our investigation was to compare the distribution of dermatomycosis species in Eastern Croatia between two different periods: first period from 1997-2001 year, and second period from 1986-88 year. The outpatients from Department of Dermatovenerology University Hospital "Osijek" with confirmed diagnosis infection. Tinea, were selected on the basis o age, gender, localization and dermatomycosis species. During the first period (1997-2001) among 75,691 outpatients Tinea infection was confirmed in 558 (0.73%), while in the second period among 47,832 outpatients there were 126 (0.26%) cases with Tinea, what showed significant increase of fungal infections among population this region. According the age and gender in both periods predominant population were under of the age 16(40.14%: 41.26%), and female population was predominant (58.60% and 57.14%) in comparison to males (41.39% and 42.85%). The most frequent localization of lesions in period I were cutis glabrae (47.31%), palms and soles (31.36%), capitis (17.38%) and unguis (9.31%) and isolated species were as followed: Trichophyton (39.06%), Microsporum (31.72%) and Candida (28.13%) species. In period II the most frequent localization were palms and soles (40.47%), cutis glabrae (36.50%), capitis (12.69%) and unguis (10.31%). The isolated species in this period were: Trichophyton (80.15%), Candida (12.69%) and Microsporum (4.76%) species. From the data collected during two different periods we can observe 1) increase of fungal infection generally in our region; 2) significant changes in causative species (increase of Microsporum and Candida species infection, but Trichophyton spp still remain the first causative agent); and 3) changes in the localization of lesions.     

Hydroponic systems: exploring the balance between co-cultivation of Chlorella vulgaris and Swiss chard (Beta vulgaris L. subsp. cicla)

Journal of Applied Phycology - Co-cultivation of plants and microalgae represents an optimized production method which is less resource intense and it is ecologically correct and clean....     

Selective BRAFV600E inhibitor PLX4720, requires TRAIL assistance to overcome oncogenic PIK3CA resistance

Documented sensitivity of melanoma cells to PLX4720, a selective BRAFV600E inhibitor, is based on the presence of mutant BRAF(V600E) alone, while wt-BRAF or mutated KRAS result in cell proliferation. In colon cancer appearance of oncogenic alterations is complex , since BRAF, like KRAS mutations, tend to co-exist with those in PIK3CA and mutated PI3K has been shown to interfere with the successful application of MEK inhibitors. When PLX4720 was used to treat colon tumours, results were not encouraging and herein we attempt to understand the cause of this recorded resistance and discover rational therapeutic combinations to resensitize oncogene driven tumours to apoptosis. Treatment of two genetically different BRAF(V600E) mutant colon cancer cell lines with PLX4720 conferred complete resistance to cell death. Even though p-MAPK/ ERK kinase (MEK) suppression was achieved, TRAIL, an apoptosis inducing agent, was used synergistically in order to achieve cell death by apoptosis in RKO(BRAFV600E/PIK3CAH1047) cells. In contrast, for the same level of apoptosis in HT29(BRAFV600E/PIK3CAP449T) cells, TRAIL was combined with 17-AAG, an Hsp90 inhibitor. For cells where PLX4720 was completely ineffective, 17-AAG was alternatively used to target mutant BRAF(V600E). TRAIL dependence on the constitutive activation of BRAF(V600E) is emphasised through the overexpression of BRAF(V600E) in the permissive genetic background of colon adenocarcinoma Caco-2 cells. Pharmacological suppression of the PI3K pathway further enhances the synergistic effect between TRAIL and PLX4720 in RKO cells, indicating the presence of PIK3CA(MT) as the inhibitory factor. Another rational combination includes 17-AAG synergism with TRAIL in a BRAF(V600E) mutant dependent manner to commit cells to apoptosis, through DR5 and the amplification of the apoptotic pathway. We have successfully utilised combinations of two chemically unrelated BRAF(V600E) inhibitors in combination with TRAIL in a BRAF(V600E) mutated background and provided insight for new anti-cancer strategies where the activated PI3KCA mutation oncogene should be suppressed.