To examine the effect on biological activity of replacing D-Cys in the opioid peptide H-Tyr-c[D-Cys-Gly-Phe(pNO(2))-D-Cys]-NH(2) in position 2 or/and 5 with alpha-hydroxymethylcysteine (alpha-Hmc), three analogues were synthesized. These compounds exhibit agonist activity at both mu and delta receptors. However, the most active analogue, with (S)-alpha-Hmc residue in position 5, was 3360- and 2190-fold less active than the parent peptide in the GPI and MVD assays, respectively.
View Article and Find Full Text PDFIn order to evaluate the role and influence of the methionine residue on the biological activity of cyclolinopeptide B, an analogue with methionine residue in position 7 replaced by the amphiphilic (S)-alpha-hydroxymethylmethionine residue was synthesized. This peptide exhibits high immunosuppressive activity in the cellular, and to a lesser degree in the humoral immune response, comparable to that of CsA. In addition, the peptide was devoid of toxicity, even at high doses.
View Article and Find Full Text PDFThe two diastereomeric tripeptides f-(S)-HmMet-Leu-Phe-OMe and f-(R)-HmMet-Leu-Phe-OMe, analogues of the prototypical chemoattractant f-Met-Leu-Phe-OH, were synthesized in solution by classical methods and fully characterized. A conformational study was performed in solution by 1H-NMR. Concomitantly, the two peptides were tested for their ability to induce chemotaxis, superoxide anion production and lysozyme secretion from human neutrophils.
View Article and Find Full Text PDFCerebral circulation in 21 patients with subacute (SSH) and chronic subdural hematoma (CSH) were studied by computerized rheoencephalography before and after induction of general anesthesia. ECG and REG courses were sampled with a frequency of 62.5 Hz during a period of 15 minutes, and both sets of data points were fitted by an cubic polynomials.
View Article and Find Full Text PDFThe study group consisted of 17 patients after severe cranio-cerebral injuries-in GCS below 8. Saturation in both jugular bulbs was measured by using fiberoptic catheters, the concentration of lactate taken from jugular bulbs was measured too. These values were compared to concentration in peripheral arteries.
View Article and Find Full Text PDF