Pemetrexed and cisplatin with concurrent radiotherapy for locally advanced non-small cell and limited disease small cell lung cancer: results from 2 phase I studies.

Background: The objectives were to determine the maximum tolerated dose (MTD) of pemetrexed and cisplatin with concurrent radiotherapy. Secondary objectives include incidence and nature of acute and late toxicities, tumor response and overall survival.

Patients And Methods: Treatment naïve patients received 1 cycle of cisplatin 80 mg/m(2) in study I (stage III NSCLC), 75 mg/m(2) in study II (LD-SCLC) and pemetrexed 500 mg/m(2) before the phase I part.

Specific binding of nisin to the peptidoglycan precursor lipid II combines pore formation and inhibition of cell wall biosynthesis for potent antibiotic activity.

Unlike numerous pore-forming amphiphilic peptide antibiotics, the lantibiotic nisin is active in nanomolar concentrations, which results from its ability to use the lipid-bound cell wall precursor lipid II as a docking molecule for subsequent pore formation. Here we use genetically engineered nisin variants to identify the structural requirements for the interaction of the peptide with lipid II. Mutations affecting the conformation of the N-terminal part of nisin comprising rings A through C, e.

Engineering a disulfide bond and free thiols in the lantibiotic nisin Z.

The antimicrobial peptide nisin contains the uncommon amino acid residues lanthionine and methyl-lanthionine, which are post-translationally formed from Ser, Thr and Cys residues. To investigate the importance of these uncommon residues for nisin activity, a mutant was designed in which Thr13 was replaced by a Cys residue, which prevents the formation of the thioether bond of ring C. Instead, Cys13 couples with Cys19 via an intramolecular disulfide bridge, a bond that is very unusual in lantibiotics.

Use of the cell wall precursor lipid II by a pore-forming peptide antibiotic.

Resistance to antibiotics is increasing in some groups of clinically important pathogens. For instance, high vancomycin resistance has emerged in enterococci. Promising alternative antibiotics are the peptide antibiotics, abundant in host defense systems, which kill their targets by permeabilizing the plasma membrane.