Human skin penetration of a copper tripeptide in vitro as a function of skin layer

We study a set of 28 GRB light-curves detected between 15 December 2002 and 9 June 2003 by the anti-coincidence shield of the spectrometer (SPI) of INTEGRAL. During this period it has detected 50 bursts, that have been confirmed by other instruments, with a time resolution of 50 ms. First, we derive the basic characteristics of the bursts: various duration measures, the count peak flux and the count fluence. Second, a sub-sample of 11 bursts with 12 individual, well-separated pulses is studied. We fit the pulse shape with a model by Kocevski et al. (2003) and find that the pulses are quite self-similar in shape. There is also a weak tendency for the pulses with steep power-law decays to be more asymmetric. Third, the variability of the complex light-curves is studied by analyzing their power-density-spectra (PDS) and their RMS variability.
The averaged PDS, of the whole sample, is a power-law with index of $1.60\pm0.05$ and a break between 1–2 Hz. Fourth, we also discuss the background and noise levels. We found that the background noise has a Gaussian distribution and its power is independent of frequency, i.e., it is white noise. However, it does not follow a Poisson statistic since on average the variance is ~1.6 larger than the mean. We discuss our results in context of the current theoretical picture in which GRBs are created in an anisotropic, highly relativistic outflow from collapsing massive stars. Finally, we note that the exact behaviour of the instrument is not yet known and therefore the above results should be treated as preliminary.

Human skin penetration of a copper tripeptide in vitro as a function of skin layer

Objective and designSkin retention and penetration by copper applied as glycyl-L-histidyl-L-lysine cuprate diacetate was evaluated in vitro in order to assess its potential for its transdermal delivery as an anti-inflammatory agent.Materials and methodsFlow-through diffusion cells with 1 cm(2) exposure area were used under infinite dose conditions. 0.68% aq. copper tripeptide as permeant was applied on isolated stratum corneum, heat-separated epidermis and dermatomed skin and receptor fluid collected over 48 h in 4 h intervals using inductively coupled plasma mass spectrometry to analyze for copper in tissues and receptor fluid.ResultsThe permeability coefficient of the compound through dermatomed skin was 2.43 ± 0.51 × 10(-4) cm/h; 136.2 ± 17.5 μg/cm(2) copper permeated 1 cm(2) of that tissue over 48 h, while 97 ± 6.6 μg/cm(2) were retained as depot.ConclusionsCopper as tripeptide was delivered in potentially therapeutically effective amounts for inflammatory disease

Tecnica SdFFF ed estrazione selettiva

La Sedimentation Field Flow Fractionation (SdFFF) è una tecnica separativa ad alta risoluzione di ampia applicazione nella caratterizzazione dei sistemi dispersi. Campioni di materiale particolato sospeso nel fiume Po e di particolato atmosferico, raccolto nell’area urbana di Ferrara ed opportunamente trattato, sono esempi di possibili applicazioni della tecnica SdFFF, accoppiata a tecniche spettroscopiche, per la separazione dimensionale di colloidi ambientali e della determinazione di alcuni metalli

Chiral Ligand-Exchange Chromatography on a RP-HPLC Column Coated with a New Chiral Selector Derived from L-Spinacine

A commercial reversed-phase (RP) C18 HPLC column has been dynamically coated with the chiral selector N<n-decyI-L-spinacine and then loaded with copper(ll) ions. Several racemic mixtures of underivatized amino acids and oligopeptides were resolved on the column by chiral ligand-exchange chromatography. The most important experimental conditions affecting column efficiency, retention, and selectivity (temperature and mobile phase flow rate and composition) were extensively investigated

Separation and Elemental Characterization of water born particles

Current methods by Field Flow Fractionation of river colloids are reviwed

CARATTERIZZAZIONE DIMENSIONALE ED ELEMENTALE DEL PARTICOLATO ATMOSFERICO MEDIANTE APPROCCIO INTEGRATO SDFFF/AAS/ICP-AES

L’inquinamento atmosferico è un fenomeno dinamico molto complesso determinato dalla presenza di sostanze indesiderate che, per qualità o quantità o lunga permanenza, compromettono la salubrità dell’aria, risultando pericolose per la salute dell’uomo e dannose per i materiali esposti. Il materiale particolato sospeso è una importante componente dell’atmosfera che viene studiata e controllata come indicatore di inquinamento, principalmente a causa dell’impatto negativo che ha sulla salute dell’uomo, dato che il materiale più fine di cui si compone, penetrando nelle vie respiratorie, può indurre alterazioni gravi delle mucose bronchiali, anche in virtù della sua capacità di veicolazione e di diffusione dei metalli pesanti ad esso associati, inquinanti prioritari conclamati. In questo contesto risulta interessante la caratterizzazione dimensionale ed elementale del particolato atmosferico per valutarne l’impatto ambientale. Si riportano qui alcuni risultati di uno studio di caratterizzazione dimensionale ed elementale di questa matrice ambientale, condotto attraverso un approccio metodologico di tecniche separative, la tecnica di Field Flow Fractionation (FFF), accoppiate con tecniche identificative di tipo spettroscopico (AAS e ICP-AES)1,2,3. La metodologia è applicata a campioni di PTS e PM10, prendendo in considerazione alcuni metalli di maggior interesse ambientale, quali Cd, Cr, Cu, Mn, Pb, Ni e Fe. Viene sottolineata la possibilità della metodologia sviluppata di fornire informazioni sul carico inquinante di metalli pesanti in funzione delle dimensioni delle particelle considerate, in maniera integrata

Synthesis of glycil-L-spinacine and study of its protonation and Cu(II) complex-formation equilibria, in aqueous solution

A new dipeptide, glycil-L-spinacine, has been synthesised and fully characterised. Protonation constants have been determined and binary Cu(II) complex formation equilibria investigated in an aqueous solution (25 °C, I = 0.1 mol dm-3, KNO3) using the potentiometric and spectrophotometric techniques. Mononuclear and binuclear complex species have been found to form. Binding sites and structure hypotheses are discussed on the basis of available experimental and literature data