Peptides of synthesis are a very new strategy in cosmetic science and technology for at least two reasons: (1) they are small molecules, easily penetrable in the skin and (2) they are able to induce a very specific action, because all skin cells (keratinocytes, fibroblasts, nervous cells) have membrane receptors for peptides. This group of cosmeceutics includes the botox-like peptides, represented by acetyl hexapeptide 3 (Argireline) and pentapeptid-3 (Leuphasyl). The latter is less known and has been less studied. This substance inhibits the neuromuscular synapses in the mimic muscles, acting as enkephalins. It links the enkephalin receptor to nervous cells, thereby modulating the release of acetylcholine in synaptic space. This cellular activity will be translated in vivo in a relaxation of the muscle and a reduction of expression wrinkles. The aim of our study is to evaluate the optimal concentration of Leuphasyl for skin application at the mimic muscle level, the efficiency and the safety of this peptide. We formulated three emulsions of different concentrations (0.5%, 1%, 2%) which were applied to the skin, at the level of mimic muscles (1) at the eyebrows zone (above the corrugator supercilii muscle) and (2) at the periorbital zone (above the orbicularis oculi muscle). We evaluated the regression of the wrinkles between the eyebrows using an imagistic method: pro-derm Analyser. The study is of interest to discussions concerning how to apply these kinds of cosmetic products at the mimic muscle skin level and not at the level of the wrinkles.
This paper presents an experimental work regarding the optimal conditions of pH for removing mercury from a contaminated soil sample using 0,1M solution of KI. A test stand with a column packed with contaminated soil has been done. A KI solution with neutral pH passes through the column, then a KI solution with acidic pH passes through another similar column and a KI solution with basic pH through the third column. It was collected periodically 10 mL fraction volume. The extracted mercury concentration from the solution is determined by atomic absorption spetrophotometry The results shows that the optimal conditions for cleaning the soil are using an acidic KI solution with a pH = 1, 5 � 2 and 150 mL of KI solution meaning 15 fractions of 10 mL each.
The redox electrode potential of cyanidin was determined both by experimental (cyclic voltammetry) and theoretical methods, at the HF/6--311G(d) level of theory. An isodesmic reaction scheme, involving 1,2-benzoquinone as reference molecules, was proposed for the computation of the electrode potential of cyanidin. The results of the ab initio computations were in reasonable agreement with the available experimental measurements; the differences between experiment and theory were within the range of 0.02-0.05 V. Geometric parameters of the six more stable conformers of cyanidin were computed, as well as the properties, such as atomic charges and contribution to the HOMO (highest occupied molecular orbital) energies, of each hydroxyl group of cyanidin.
Arterial endothelium produces a large ramge of active factors which are indispensable for modulation of vasomotor tone and maintenance of vascular wall integrity. From these factors, nitric oxide (NO), wich is released by the endothelial cells as a response to acetylcholine or adenosine action on specific receptors, plays an important role.NO is the result of oxidation process of L-arginine into L-citrulline, under the action of endothelial nitric oxide synthase (NOSe), wich is activated by intracelluar Ca2+ - calmodulin complex . Our study, performed in isolated organ bath, analyzed vascular reactivity of 12 guinea pigs� thoracic aorta rings. After phenylephrine -PHE 10-5 mol/L precontraction, the dose-effect curves for acetylcoline � ACH, adenosine 5� phosphate - 5�ADP and sodium nitroprusside � SNP were determined, before and after incubation of preparation, for 1 hour, with 5% hydrosoluble cigarettes smoke extract (CSE). Statistic analysis, performed with the use of t pair test and ANOVA parametric test, showed that incubation of vascular preparation with 5% CSE has increased the contractile response to PHE 10-5 mol/L (p[0.05), has reduced the endothelium-dependent relaxing response to ATP 10-5 mol/L (p[0.001) and 5�ADP 10-5 molo/L (p[0.001), but has not significantly modified the endothelium-independent relaxing response to SNP 10-5 mol/L (p=0.05). As a conclusion, vascular rings incubation with 5% CSE induced a decrease of endothelium NO synthesis under the action of AXH and 5�ADP, but did not change the smooth muscle fiber respomse in the presence of NO released by SNP.
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