Bioactivity in vitro

Possibly relevant to be added to data base in vitro bioassay general toxicity (extract) in vitro bioassay thyroid hormone disruption (extract) (incl. bioactivation) in vitro estrogenicity or androgenicity (extract) Chemicals that only are toxic in high concentration (narcotics, nanoparticles) Chemical analysis of lipophillic POPs in water... 

Park, J. E., Chen, H. H., Winer, J., Houck, K. A., and Ferrara, N. 1994. Placenta growth factor. Potentiation of vascular endothelial growth factor bioactivity, in vitro and in vivo, and high affinity binding to Flt-1 but not to Flk-l/KDR. J. Biol. Chem. 269 25646-25654. 

In addition to the size, also the shape of NMs was shown to play a role in induction of toxicity. NMs made of the same material but in different shapes can be differently internalized into the cells, react with cell membranes, and produce different oxidative effects [6, 14]. Carbon nanomaterials with different geometric structures (single-walled carbon nanotubes [SWCNTs], MWCNTs, and fullerenes) were shown to exhibit quite different cytotoxicity and bioactivity in vitro [15]. The uptake of Au nanospheres and nanorods was also significantly different, illustrating the role of the shape on NM internalization [6, 48],... 

Early discovery also makes extensive use of in vitro and cell-culture activity models. Activity measurements can be inconsistent when the compound has low aqueous solubility. Thus, the solubility assay, can assist with the interpretation of biological activity tests. Another cause of poor bioactivity in vitro is poor stability in the assay medium. Also, there can be discrepancies with activity when compounds are moved from biological models in 96-384-well format to living-cell models. Differences in activity can often be traced to permeability of the compound through the cellular lipid membrane and correlate with results of the permeability assay. 

The quaternary pteleatinium chloride (CieH2o04N Cl mp 267-270°) isolated from this plant was shown to he bioactive in vitro against Mycobacterium smegmatis and Candida albicans. When heated with pyridine it generates compound 185 (R = H) which on treatment with diazomethane yields (+ )-balfouridine (185, R = Me) of known structure. Consequently the structure of the new base is 184 which exhaustive spectral data confirm (216). 

Pearce RE, Uetrecht JP, Leeder JS. Pathways of carbamazepine bioactivation in vitro II. The role of human cytochrome P450 enzymes in the formation of 2-hydroxyiminostlibene. Drug Metab Dispos 2005 33 1819-1826. 

G. Lutisanova, M. T. Palou, and J. Kozankova, Comparison of Bioactivity in vitro of Glass and Glass Ceramic Materials during Soaking in SBF and DMEM Medium, Ceramics-Silikaty, 55, 199-207 (2011). 

Synthesis of stmctural analogues or peptide mimetics to validate bioactivity In vitro and in vivo... 

There have been notable successes in the replacement of individual peptide residues by peptoid monomers with retention of in vitro activity and enhancement of specificity. Unfortunately, attempts to completely transform those bioactive peptides that function via specific peptide-protein binding events into entirely pep-toid-based ohgomers have so far proven successful only at short chain lengths (e.g. [23]). It remains to be seen whether any general strategy can be developed in... 

It has been demonstrated that a variety of different polyphosphazenes can be developed as biomaterials, membranes or hydrogels, bioactive polymers, and bioerodible polymers. As with most new areas of polymer chemistry and biomaterials science, molecular design forms the basis of most new advances, but the rate-controlling step is the testing and evaluation of the materials in both in vitro and in vivo environments. This is particularly true for polyphosphazenes where the availability of research quantities only has limited the... 

Carmen Socaciu was bom in Cluj-Napoca, Romania and earned a BSc in chemistry in 1976, an MSc in 1977, and a PhD in 1986 from the University Babes-Bolyai in Cluj-Napoca, an important academic centre located in the Transylvania region. Dr. Socaciu worked as a researcher in medical and cellular biochemistry for more than 10 years, and became a lecturer in 1990 and full professor in 1998 in the Department of Chemistry and Biochemistry of the University of Agricultural Sciences and Veterinary Medicine (USAMV) in Cluj-Napoca. She extended her academic background in pure chemistry (synthesis and instrumental analysis) to the life sciences (agrifood chemistry and cellular biochemistry). Her fields of competence are directed especially toward natural bioactive phytochemicals (carotenoids, phenolics, flavonoids), looking to advanced methods of extraction and analysis and to their in vitro actions on cellular metabolism, their effects as functional food ingredients, and their impacts on health. 

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