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Radical scavenging activity is involved in aging processes, antiinflammatory, anticancer and wound healing activity. Hence, in the present study the DPPH radical scavenging activity of a natural product that possesses biological properties, an extract of Crocus sativus L. (saffron), grown in Crocos, Kozani (Greece), and some of its bioactive constituents (crocin, safranal) was studied. It was shown that a methanol extract of Crocus sativus exhibited high antioxidant activity, although it contains several active and inactive constituents. In trying to approximate a structure-activity relationship, two bioactive constituents of saffron extract were tested, namely crocin and safranal. Crocin showed high radical scavenging activity (50% and 65% for 500 and 1,000 ppm solution in methanol, respectively), followed by safranal (34% for 500 ppm solution). All the tested samples showed high radical scavenging activity, probably due to the ability to donate a hydrogen atom to the DPPH radical.Thus, saffron grown in Greece can be used promisingly in functional foods, drinks with antioxidant activity, in pharmaceutical and cosmetic preparations for their antioxidant activity and probably for their antiaging activity. Saffron can also be used internally in the form of powder or other pharmacotechnical formulae as a food supplement with antioxidant properties.

Alkannin and shikonin (A[sol ]S) are pharmaceutical substances with a wide spectrum of biological properties. Radical scavenging activity is involved in aging processes, antiinssammatory, anticancer and wound healing activities. Hence, in the present study the DPPH radical scavenging activity of alkannin and shikonin, both monomeric and oligomeric, and extracts of Alkanna tinctoria roots were studied and a structure-activity relationship was approximated. It was shown that both monomeric and oligomeric alkannin and shikonin and also A[sol ]S esters exhibited extremely high radical scavenging activity. The presence of the naphthoquinone moiety seems to be essential for that activity, while the side chain of A[sol ]S possibly plays a minor role. Esterification of A[sol ]S on the side chain hydroxyl group does not affect radical scavenging activity. Organic solvents and olive oil (extracted at room temperature) extracts of Alkanna tinctoria roots, which contain as active ingredients A[sol ]S esters, exhibited very good antiradical activity. Alkannin and shikonin and their esters and also extracts of Alkanna tinctoria roots could be used promisingly in pharmaceutical and cosmetic preparations for their radical scavenging activity and probably for their antiaging activity., (Copyright 2005 John Wiley & Sons, Ltd.)

Microcapsules, containing the pharmaceutical substance shikonin, were prepared by the solvent evaporation method in order to enhance shikonin stability (reduce photo-oxidation, polymerization), decrease its hydrophobicity and control its release rate. The effect of various parameters, such as type of polymer, type and concentration of surfactant, solvent volume and mastic gum (Pistacia lentiscus resin) content/concentration as core additive, on the characteristics of the produced microcapsules and the release rate of shikonin, were experimentally investigated. Among the polymers tested for matrix, ethylcellulose (EC) of viscosity 10 cp was the most successful; EC 100 cp and mastic gum result in larger/compact particles with no pores and much slower release. Sodium dodecyl sulphate (SDS) results in microcapsules with desirable morphological and physicochemical characteristics, while polyethylene glycol (PEG) and polyvinyl alcohol (PVA) are not indicated as surfactants in shikonin microencapsulation. Decreasing the solvent volume (dichloromethane) results in increased mean particle size and, thus, in slower release rate of shikonin, while the incorporation of mastic gum in the capsule core results in better control of shikonin release. Finally, the combination of EC 10 cp as matrix, mastic gum as core additive, low dichloromethane (DCM) volume and low SDS concentration results in microcapsules with the best characteristics in terms of efficiency, loading, release and particle size distribution.

Semantic or vocabulary errors were measured among children with autism and mild learning disability and children with mild learning disability only (six children of 7.9-8.7 years in each group), testing the hypothesis that these were common in both groups. Different variables were investigated such as breadth of vocabulary and number of vocabulary errors, type of paraphasias, and mechanisms used to name the meanings that children were not aware of or could not recall, and the particular meanings that were difficult for each group. Preliminary findings showed that vocabulary errors were similar in both groups, except under-extension, which was not used by the autism group. Children with autism tended to use all mechanisms in order to name something they did not know and to focus on parts of the object in order to name it, while unknown words were similar in both groups.

Quinones are of significant interest due to their important role in specific cellular functions. Quinoproteins are a big class of oxyreductive agents occurring in bacteria and other organisms. In this investigation derivatives of 2-amino-1,4-benzoquinone, 2-amino-1,4-naphthoquinone and 2-amino-5,8-dihydroxy-1,4-naphthoquinone with a di- and a tripeptide were prepared for first time. The effect of the synthesized compounds on sister chomatid exchange (SCE) rates and human lymphocyte proliferation kinetics on a molar basis was studied. Among these coupled products the most effective in inducing SCEs and depressing proliferation rate indices is the coupling product of 2-amino-1,4-naphthoquinone with the tripeptide GHK (10). Next in order of magnitude in inducing cytogenetic effects is 2-amino-1,4-naphthoquinone (2) and its coupling products with glycine and serine (4 and 5), while the rest displayed marginal activity.

This paper describes the pattern of psychopathology in a sample of 95 children of 8-13 years, who had experienced war in Bosnia. The children were assessed with a battery of standardised measures during a psychosocial support programme in Northern Greece. They either came from refugee families (44%) or had suffered significant family loss (a parent had been killed in 28% and the father was injured or absent in 27% of cases). Children recalled a substantial number of war traumatic experiences. According to previously established cut-off scores on self-report measures, 45 children (47%) scored within the clinical range on the Depression Self-Rating Scale for Children, 28 (23%) on the Revised Children's Manifest Anxiety Scale, and 65 (28%) on the Impact of Event Scale (IES) measuring PTSD reactions. There was a significant association between the number of war traumatic experiences and the intrusion and avoidance scores on the IES. The findings are discussed in relation to setting up intervention programmes for children victims of war and their families.

The essential oils of the hybrid MENTHA X ROTUNDIFOLIA (L.) Huds. growing wild in Greece were investigated by means of GLC and GLC-MS. Two chemotypes have been found, which are characterized by the main components piperitone oxide and menthyl acetate, respectively. The latter is a new chemotype of M. X ROTUNDIFOLIA.

The essential oils from 9 populations of MENTHA LONGIFOLIA (L.) L., ssp. LONGIFOLIA and ssp. PETIOLATA (Boiss.) Kokkini, growing wild in Greece, were investigated by means of GLC and GLC-MS. Piperitone oxide has been found as the main component in the essential oils of both subspecies while carvone only in some individuals of ssp. PETIOLATA (chemotype 2).