A new seco-tremulane, 11,12-epoxy-5,6-secotremula-1,6(13)-dien-5,12-olide (1), was isolated together with the known compounds, conocenolides A (2) and B (3), tremulenediol A (4), tremulenolide A ...(5), and two lanostane triterpenoids, trametenolic acid B (6), and pinicolic acid A (7), from cultures of the basidiomycete Flavodon flavusBCC 17421. Interconversion of conocenolides A/B was demonstrated. Compound 1 exhibited weak cytotoxic activities, whereas tremulenediol A showed antiplasmodial activity (IC50 8.6 µg/ml). Pinicolic acid A exhibited activity against herpes simplex virus type-1 (IC50 15 µg/ml) as well as cytotoxic activities.
BackgroundOur production unit realises more than 35 000 cytotoxic drug preparations per year in an isolator chamber (IC). The control method is done by in-process gravimetric analysis coupled with ...scan identification, led by software with interactive instructions. The balances are certified once a year, yet outside the IC. Indeed, turbulent airflow could impact the scales’ measurements. The accepted errors percentages are a function of the volumes weighted.PurposeAfter software development and setup, we need to validate this control method with the two components: the weighing scales and the software.Material and methodsFor the weighting scales, a qualification was made inside and outside the IC with standard weights. For the validation the tests performed were fidelity, accuracy and eccentricity. Then, a comparison to visual control was performed to evaluate the bias of the balance. Six syringes with different volumes were made and then verified by a third person. Next, they were weighed 15 times to obtain the total error. For the software, a method is being developed to analyse the specificity and the sensitivity. For the specificity, an extraction of the software was done to study the forced steps (the steps refused by the software but accepted by the pharmacist because of the correct volume read) over a period of 6 months.ResultsThe metrological tests enable to qualify the balances. The bias of the weighing scales fluctuates between 0.94% and 4.40%. Over 6 months, 15 227 preparations were realised with a total of 1 89 334 steps including 49 180 weighing steps. Among those, there were 2023 forced steps (4.1%). The most forced cytotoxic molecules were identified. The two most forced stages were the weighing of the syringe with cytotoxic (41%) and of the final pouch (23%). The 50 ml syringe is responsible for 41% of this forced stage and, in 85% of the cases, it is because the volume to collect has a decimal value.ConclusionConcerning the sensitivity, a method is elaborated to determine the rate of the false negatives with a fake cytotoxic preparations plan and calculated weighing errors. Our method validation plan is complete with the validation of the two components: precision scale and software.References and/or acknowledgementsNo conflict of interest.
NK cells use a variety of receptors to detect abnormal cells, including tumors and their metastases. However, in the case of melanoma, it remains to be determined what specific molecular interactions ...are involved and whether NK cells control metastatic progression and/or the route of dissemination. Here we show that human melanoma cell lines derived from LN metastases express ligands for natural cytotoxicity receptors (NCRs) and DNAX accessory molecule-1 (DNAM-1), two emerging NK cell receptors key for cancer cell recognition, but not NK group 2 member D (NKG2D). Compared with cell lines derived from metastases taken from other anatomical sites, LN metastases were more susceptible to NK cell lysis and preferentially targeted by adoptively transferred NK cells in a xenogeneic model of cell therapy. In mice, DNAM-1 and NCR ligands were also found on spontaneous melanomas and melanoma cell lines. Interference with DNAM-1 and NCRs by antibody blockade or genetic disruption reduced killing of melanoma cells. Taken together, these results show that DNAM-1 and NCRs are critical for NK cell-mediated innate immunity to melanoma cells and provide a background to design NK cell-based immunotherapeutic strategies against melanoma and possibly other tumors.
Increased levels of nicotinamide/nicotinic acid mononucleotide adenylyltransferase (NMNAT) act as a powerful suppressor of Wallerian degeneration and ataxin- and tau-induced neurodegeneration in ...flies and mice. However, the nature of the suppression mechanism/s remains controversial. Here, we show that in yeast models of proteinopathies, overexpression of the NMNAT yeast homologs, NMA1 and NMA2, suppresses polyglutamine (PolyQ) and alpha -synuclein-induced cytotoxicities. Unexpectedly, overexpression of other genes in the salvage pathway for NAD super(+) biosynthesis, including QNS1, NPT1 and PNC1 also protected against proteotoxicity. Our data revealed that in all cases, this mechanism involves extensive clearance of the non-native protein. Importantly, we demonstrate that suppression by NMA1 does not require the presence of a functional salvage pathway for NAD super(+) biosynthesis, SIR2 or an active mitochondrial oxidative phosphorylation (OXPHOS) system. Our results imply the existence of histone deacetylase- and OXPHOS-independent crosstalk between the proteins in the salvage pathway for NAD super(+) biosynthesis and the proteasome that can be manipulated to achieve cellular protection against proteotoxic stress.
Four series of nucleolipids with either uridine, 5-methyluridine, 5-fluorouridine, and 6-azauridine as beta-D-ribonucleoside component have been prepared in a combinatorial (not parallel!) manner ...(see Formulae). All compounds have been characterized by elemental analyses, ESI mass spectrometry as well as by 1H-, and 13C-NMR, and UV spectroscopy. A selection of eight nucleolipids with different lipophilizing moieties, based on earlier findings, as well as of 5-fluorouridine as control were first tested on their cytotoxic effect towards PMA-differentiated human THP-1 macrophages. Those compounds which did not exhibit a significant inhibitory effect on the survival of the macrophages were next tested on their cytostatic/cytotoxic effect towards the human astrocytoma/oligodendroglioma GOS-3 cells as well as against the rat malignant neuroectodermal BT4Ca cell line. Additionally, induction of apoptosis of the cell lines was evaluated. It turned out that particularly a combined lipophilization of the nucleosides by an 2',3'-O-ethyl levulinate residue plus a farnesyl moiety at N(3) of the pyrimidine moiety of the corresponding nucleolipids leads to an active compound with the highest probability.
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