11 research outputs found
In vitro antitumor actions of extracts from endemic plant Helichrysum zivojinii
Background: The aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Cernjavski & Soska (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC). Methods: The aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors. Results: The investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways. Conclusion: Extracts obtained from the endemic plant Helichrysum zivojinii may represent an important source of novel potential antitumor agents due to their pronounced and selective cytotoxic actions towards malignant cells
Analysis of International Mergers and Acquisitions in the Pharmaceutical Industry
Brojna su istraživanja koja analiziraju spajanja i preuzimanja, no veÄina ih se ne fokusira na neku odreÄenu
industriju, veÄ uzorak obuhvaÄa poduzeÄa iz razliÄitih industrija. Ovaj se rad fokusira na spajanja i
preuzimanja u farmaceutskoj industriji. Pretpostavke su da farmaceutska poduzeÄa neiskusna u spajanju
i preuzimanju postižu bolje rezultate u relativno malim, domaÄim spajanjima i preuzimanjima, dok su
farmaceutska poduzeÄa s veÄim iskustvom u spajanjima i preuzimanjima uspjeÅ”na i u veÄim i u meÄunarodnim
spajanjima i preuzimanjima. VeÄa spajanja i preuzimanja te meÄunarodna spajanja i preuzimanja
sama po sebi sadrže veÄi rizik za preuzimatelja, pa neiskustvo u spajanju i preuzimanju dodatno poveÄava
rizik prilikom provedbe posla. Takvo poveÄavanje rizika u prosjeku rezultira loÅ”ijim povratima za dioniÄare
farmaceutskih poduzeÄa.There are numerous researches which analyze mergers and acquisitions, but most of them do not
focus on a certain industry, but their sample considers companies from different industries. This paper
focuses on mergers and acquisitions in the pharmaceutical industry. It is assumed that pharmaceutical
companies with no experience in mergers and acquisitions achieve better results in relatively small and
domestic mergers and acquisitions while pharmaceutical companies with greater experience in mergers
and acquisitions are successful even in bigger and international mergers and acquisitions. Bigger mergers
and acquisitions and international mergers and acquisitions are more risky for the companies so lack of
experience in mergers and acquisitions additionally increases risks during the process of mergers and
acquisitions. On average, such increase of the risk results in lower returns for stock owners of pharmaceutical
companies
<it>In vitro</it> antitumor actions of extracts from endemic plant <it>Helichrysum zivojinii</it>
Abstract Background The aim of this research was to determine the intensity and mechanisms of the cytotoxic actions of five extracts isolated from the endemic plant species Helichrysum zivojinii Äernjavski & SoÅ”ka (family Asteraceae) against specific cancer cell lines. In order to evaluate the sensitivity of normal immunocompetent cells implicated in the antitumor immune response, the cytotoxicity of extracts was also tested against healthy peripheral blood mononuclear cells (PBMC). Methods The aerial parts of the plants were air-dried, powdered, and successively extracted with solvents of increasing polarity to obtain hexane, dichloromethane, ethyl-acetate, n-butanol and methanol extracts. The cytotoxic activities of the extracts against human cervix adenocarcinoma HeLa, human melanoma Fem-x, human myelogenous leukemia K562, human breast adenocarcinoma MDA-MB-361 cells and PBMC were evaluated by the MTT test. The mode of HeLa cell death was investigated by morphological analysis. Changes in the cell cycle of HeLa cells treated with the extracts were analyzed by flow cytometry. The apoptotic mechanisms induced by the tested extracts were determined using specific caspase inhibitors. Results The investigated Helichrysum zivojinii extracts exerted selective dose-dependent cytotoxic actions against selected cancer cell lines and healthy immunocompetent PBMC stimulated to proliferate, while the cytotoxic actions exerted on unstimulated PBMC were less pronounced. The tested extracts exhibited considerably stronger cytotoxic activities towards HeLa, Fem-x and K562 cells in comparison to resting and stimulated PBMC. It is worth noting that the cytotoxicity of the extracts was weaker against unstimulated PBMC in comparison to stimulated PBMC. Furthermore, each of the five extracts induced apoptosis in HeLa cells, through the activation of both intrinsic and extrinsic signaling pathways. Conclusion Extracts obtained from the endemic plant Helichrysum zivojinii may represent an important source of novel potential antitumor agents due to their pronounced and selective cytotoxic actions towards malignant cells.</p
Cancer-Suppressive Potential of Extracts of Endemic Plant Helichrysum zivojinii: Effects on Cell Migration, Invasion and Angiogenesis
Helichrysum zivojinii Cernjavski & Soska is an endemic plant species that grows in the National Park Galicica in Macedonia. Five extracts were isolated as fractions from the aerial parts of the plant: a n-hexane extract (1), a dichloromethane extract (2), an ethyl-acetate extract (3), a n-butanol extract (4) and a methanol extract (5). A dose-dependent cytotoxic activity of the extracts on MDA-MB-231 and EA.hy926 cells was observed. Extracts exhibited more pronounced cytotoxic actions on MDA-MB-231 cells than on EA.hy926 cells. The n-hexane extract (1), at a non-toxic concentration, exhibited an inhibitory effect on the migration as well the invasiveness of MDA-MB-231 cells. The dichloromethane extract (2), at a non-toxic concentration, demonstrated inhibition of MDA-MB-231 cells invasion. Each of the five extracts applied at non-toxic concentrations inhibited migration of EA.hy926 cells. The prominent inhibitory effect of the n-hexane extract on EA.hy926 cells migration was associated with a notable anti-angiogenic action of this extract. The other four tested extracts demonstrated mild anti-angiogenic activity. Our data highlight the prominent anticancer potential of n-hexane (1) and dichloromethane (2) extracts, which could be attributed to their very pronounced and selective cytotoxic activities as well as their anti-invasive and anti-angiogenic properties