Razporejanje mikrotubulov v celicah V-79 po delovanju citohalazina B

Background. The aim of this work was to study the configuration of the microtubules in the cytochalasin B treated V-79 cells in connection to the cell shape and to see whether there are any similarities to the phenomena taking place in phospholipid vesicles. Subjects and methods. An experiment wasperformed where cytochalasin B was added to the V-79 cells (lung fibroblasts of Chinese hamster). Results. The cell shape changed from an elongated one into the shape with a profile resembling the Greek letter phi. The microtubules were found to be organized into a rod within the symmetry axis of the cell. Conclusion. As similar shapes were previously observed also in the phospholipid vesicles with entrapped microtubule rods, our results support the hypothesis that similar physical mechanisms may pertain in simple systems as well as in living cells.Izhodišča. V tej raziskavi smo proučevali razporeditev mikrotubulov celicah V-79 po delovanju citohalazina B. Poleg njihove oblike smo poskušali ugotoviti, ali je ta pojav v čemer koli podoben dogajanjem v fosfolipidnih mehurčkih. Material in metode. Opravili smo preiskus s citohalazinom B, ki smoga dodali celicam V 79 (pljučni fibroblasti kitajskega hrčka). Rezultati. Oblika celice se je spremenila iz podolgovate v obliko, katere profil je podoben grški črki fi. Mikrotubuli so se uredili v palico v simetrijski osi celice. Zaključek. Ker so podobne oblike pred tem opazili tudi pri fosfolipidnih mehurčkih, ki so vsebovali paličasto strukturo iz mikrotubulov, prikazani rezultati podpirajo hipotezo, da so podobni fizikalni mehanizmi prisotni v preprostih sistemih kot tudi v živih celicah

Biological activities of ethanolic extracts from deep-sea antarctic marine sponges

We report on the screening of ethanolic extracts from 33 deep-sea Antarctic marine sponges for different biological activities. We monitored hemolysis, inhibition of acetylcholinesterase, cytotoxicity towards normal and transformed cells and growth inhibition of laboratory, commensal and clinically and ecologically relevant bacteria. The most prominent activities were associated with the extracts from sponges belonging to the genus Latrunculia, which show all of these activities. While most of these activities are associated to already known secondary metabolites, the extremely strong acetylcholinesterase inhibitory potential appears to be related to a compound unknown to date. Extracts from Tetilla leptoderma, Bathydorus cf. spinosus, Xestospongia sp., Rossella sp., Rossella cf. racovitzae and Halichondria osculum were hemolytic, with the last two also showing moderate cytotoxic potential. The antibacterial tests showed significantly greater activities of the extracts of these Antarctic sponges towards ecologically relevant bacteria from sea water and from Arctic ice. This indicates their ecological relevance for inhibition of bacterial microfouling

Effects of periodontal dressings on fibroblasts and gingival wound healing in dogs

In the present study the effects of different commercially available periodontal dressings (Peripac, Barricaid, Fittydent, Reso-Pack and Myzotect-tincture) on fibroblast (V-79-379A) proliferation and survival were tested in vitro. Barricaid, Fittydent and Reso-Pack periodontal dressings have only small inhibitory effects on cell proliferation (83.3 ± 9%, 71.6 ± 8.7% and 87.3 ± 4.5% of control after 48 h, respectively) in comparison with the great inhibitory effect of Myzotect-tincture (2.9 ± 0.1%) and Peripac (33.7 ± 11.4%) (p < 0.001). Barricaid was the only dressing where 41% of cells survived after exposure, while the other four dressings killed all the cells in 6 days. In addition, the healing of artificially created gingival wounds covered by Barricaid and Reso-Pack was followed for 7 days in 12 Beagle dogs. Histological evaluation of gingival tissue demonstrated that wounds covered by Reso-Pack showed the best epithelisation and vascularity and the least inflammatory reaction in first 4days. Later the observed parameters were similar with those of wounds covered by Barricaid or without pack. The present results indicate that Peripac periodontal dressing and Myzotect-tincture showed the highest cytotoxicity to fibroblasts in vitro. From the histological observations in Beagle dogs Reso-Pack has been found to be the most suitable dressing, followed by Barricaid

Biological activities of ethanolic extracts from deep-sea Antarctic marine sponges

We report on the screening of ethanolic extracts from 33 deep-sea Antarctic marine sponges for different biological activities. We monitored hemolysis, inhibition of acetylcholinesterase, cytotoxicity towards normal and transformed cells and growth inhibition of laboratory, commensal and clinically and ecologically relevant bacteria. The most prominent activities were associated with the extracts from sponges belonging to the genus Latrunculia, which show all of these activities. While most of these activities are associated to already known secondary metabolites, the extremely strong acetylcholinesterase inhibitory potential appears to be related to a compound unknown to date. Extracts from Tetilla leptoderma, Bathydorus cf. spinosus, Xestospongia sp., Rossella sp., Rossella cf. racovitzae and Halichondria osculum were hemolytic, with the last two also showing moderate cytotoxic potential. The antibacterial tests showed significantly greater activities of the extracts of these Antarctic sponges towards ecologically relevant bacteria from sea water and from Arctic ice. This indicates their ecological relevance for inhibition of bacterial microfouling

Biological activities of organic extracts of four <i>Aureobasidium pullulans</i> varieties isolated from extreme marine and terrestrial habitats

<div><p>We report on the screening for biological activities of organic extracts from seven strains that represent four varieties of the fungus <i>Aureobasidium pullulans</i>, that is <i>A. pullu</i><i>l</i><i>ans</i> var. <i>melanogenum</i>, <i>A. pullulans</i> var. <i>pullulans</i>, <i>A. pullulans</i> var. <i>subglaciale</i> and <i>A. pullulans</i> var. <i>namibiae</i>. We monitored haemolysis, cytotoxicity, antioxidant capacity and growth inhibition against three bacterial species. The haemolytic activity of <i>A. pullulans</i> var. <i>pullulans</i> EXF-150 strain was due to five different haemolytically active fractions. Extracts from all of the other varieties contained at least one haemolytically active fraction. Short-term exposure of cell lines to these haemolytically active organic extracts resulted in more than 95% cytotoxicity. Strong antioxidant capacity, corresponding to 163.88 μg ascorbic acid equivalent per gram of total solid, was measured in the organic extract of the strain EXF-3382, obtained from <i>A. pullulans</i> var. <i>melanogenum</i>, isolated from the deep sea. Organic extracts from selected varieties of <i>A. pullulans</i> exhibited weak antibacterial activities.</p></div