Search results for "ship"
showing 10 items of 6731 documents
Saponins-mediated potentiation of cisplatin accumulation and cytotoxicity in human colon cancer cells.
2002
The triterpene saponins jenisseensosides A, B, C, D were found to increase the accumulation and cytotoxicity of the anticancer agent cisplatin in human colon tumor cells. These compounds are glycosides of quillaic acid whose fucose residue was acylated by a trans- or cis-p methoxycinnamic acid. In contrarst, other saponins derivatives without this acyl moiety were not found to potentiate the accumulation and cytotoxicity of cisplatin. These results suggested the importance of the acyl moiety for activity.
Cyclic heptapeptides from the soil-derived fungus Clonostachys rosea
2019
Abstract Three new cyclic heptapeptides (1–3) together with three known compounds (4–6) were isolated from a solid rice culture of the soil-derived fungus Clonostachys rosea. Fermentation of the fungus on white beans instead of rice afforded a new γ-lactam (7) and a known γ-lactone (8) that were not detected in the former extracts. The structures of the new compounds were elucidated on the basis of 1D and 2D NMR spectra as well as by HRESIMS data. Compounds 1 and 4 exhibited significant cytotoxicity against the L5178Y mouse lymphoma cell line with IC50 values of 4.1 and 0.1 µM, respectively. Compound 4 also displayed cytotoxicity against the A2780 human ovarian cancer cell line with an IC50…
Zinc overload mediated by zinc oxide nanoparticles as innovative anti-tumor agent
2017
The predicted global cancer burden is expected to surpass 20 million new cancer cases by 2025. Despite recent advancement in tumor therapy, a successful cancer treatment remains challenging. The emerging field of nanotechnology offers great opportunities for diagnosis, imaging, as well as treatment of cancer. Zinc oxide nanoparticles (ZnO NP) were shown to exert selective cytotoxicity against tumor cells via a yet unknown mechanism, most likely involving the generation of reactive oxygen species (ROS). These nanoparticles are a promising therapeutic opportunity as zinc is a nontoxic trace element and its application in medically-related products is considered to be safe. We could show that …
Multiparametric evaluation of the cytoprotective effect of the Mangifera indica L. stem bark extract and mangiferin in HepG2 cells.
2012
Abstract Objective Mango (Mangifera indica L.) stem bark extract (MSBE) is a natural product with biological properties and mangiferin is the major component. This paper reported the evaluation of the protective effects of MSBE and mangiferin against the toxicity induced in HepG2 cells by tert-butyl hydroperoxide or amiodarone. Method Nuclear morphology, cell viability, intracellular calcium concentration and reactive oxygen species (ROS) production were measured by using a high-content screening multiparametric assay. Key findings MSBE and mangiferin produced no toxicity below 500 mg/ml doses. A marked recovery in cell viability, which was reduced by the toxicants, was observed in cells pr…
Comparison of viability assays for Cryptosporidium parvum oocysts after disinfection.
2003
Abstract In order to test various viability assays for Cryptosporidium parvum oocysts were used to infect HCT-8 cells in vitro or baby mice. Infected cells were either stained with fluorescent anti- Cryptosporidium -antibody or lysed and subjected to C. parvum- specific PCR after 48 h. Titrations with infective oocysts were performed and compared to oocysts disinfected with Neopredisan © for 2 h at varying concentrations. Caecal smears and histological sections from infected animals were examined in parallel. The number of foci of parasite development in vitro after immunofluorescent staining correlated well with the infection dose. PCR was less quantifiable and the results were not always …
An organogold compound as potential antimicrobial agent against drug resistant bacteria: Initial mechanistic insights
2021
Abstract The rise of antimicrobial resistance has necessitated novel strategies to efficiently combat pathogenic bacteria. Metal‐based compounds have been proven as a possible alternative to classical organic drugs. Here, we have assessed the antibacterial activity of seven gold complexes of different families. One compound, a cyclometalated Au(III) C^N complex, showed activity against Gram‐positive bacteria, including multi‐drug resistant clinical strains. The mechanism of action of this compound was studied in Bacillus subtilis. Overall, the studies point towards a complex mode of antibacterial action, which does not include induction of oxidative stress or cell membrane damage. A number …
mRNA-induction and cytokine release during in vitro exposure of human nasal respiratory epithelia to methyl methacrylate
2007
Abstract Background Methyl methacrylate (MMA) has been reported to cause histopathological changes in rodent nasal epithelium after inhalation challenges. Data in humans are lacking. Methods In this in vitro design 22 primary cell cultures taken from inferior turbinate tissue of healthy individuals were exposed to MMA concentrations of 50 ppm (German MAK-value) and 200 ppm. mRNA expression and cytokine release of inflammatory mediators were quantified after 4 h and after 24 h. Controls were exposed to synthetic air. Q-PCR analysis was performed for TNF-α, IL-1β, IL-6, IL-8, MCP-1, GMCSF, Cox-1 and Cox-2. ELISA assays were performed from culture supernatants for TNF-α, IL-1β, IL-6, IL-8, MCP…
Synthesis and antiproliferative activity of substituted 3[2-(1H-indol-3-yl)-1,3-thiazol-4-yl]-1H-pyrrolo[3,2-b]pyridines, marine alkaloid nortopsenti…
2014
A large number of indolyl-4-azaindolyl thiazoles, nortopsentin analogues, were conveniently synthesized. The antiproliferative activity of the new derivatives was examined against four human tumor cell lines with different histologic origin. Seven derivatives consistently reduced the growth of the experimental models independently of TP53 gene status and exhibited the highest activity against the malignant peritoneal mesothelioma (STO) cell line. The most active compound of this series acts as a CDK1 inhibitor, and was found to cause cell cycle arrest at G 2 /M phase, to induce apoptosis by preventing the phosphorylation of survivin in Thr 34 and to increase the cytotoxic activity of paclit…
Antitumoural properties of benzannelated seven-membered 5-fluorouracil derivatives and related open analogues. Molecular markers for apoptosis and ce…
2005
Attention is increasingly being focussed on the cell cycle and apoptosis as potential targets for therapeutic intervention in cancer. We prepared a series of bioisosteric benzannelated seven-membered 5-FU O,N-acetals to test them against the MCF-7 human breast cancer cell line. Benzo-fused seven-membered O,O-acetals or their acyclic analogues led to the expected 5-FU O,N-acetals (or aminals), in addition to six- and 14-membered aminal structures and acyclic compounds. All the cyclic aminals provoked a G0/G1-phase cell cycle arrest, whereas Ftorafur, a known prodrug of 5-FU, and 1-[2-(2-hydroxymethyl-4-nitrophenoxy)-1-methoxyethyl]-5-fluorouracil (11) induced an S-phase cell cycle arrest. Al…
Differentiation of herpes simplex virus-induced fusion from without and fusion from within by cyclosporin A and compound 48/80.
1991
Treating strains of herpes simplex virus (HSV) in culture with either cyclosporin A or compound 48/80, allowed the strains to be divided into two groups. Group 1 contains the strains ANG and HFEM of HSV-1 and Lux syn (HSV-2) producing fusion from within (FFWI) and fusion from without (FFWO). Cyclosporin A fails to inhibit both types of fusion at concentrations up to 100 microM. Strains ANG and HFEM belong to the syn 3 marker locus group identified for HSV-1. Group 2 contains all other fusion-producing strains of HSV tested so far. Cyclosporin A inhibits FFWI at concentrations as low as 10 to 20 microM. These strains belong to the syn locus marker groups 1, 2, 4 and 5. From the fact that mut…