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There is a great interest in the relationship between Mild Cognitive Impairment (MCI) and the progression to Alzheimer's disease (AD). Several studies show the importance of oxidative stress in the pathogenesis of AD. The purpose of this study was the link between oxidative damage, MCI and AD. It analysed protein carbonyls and erythrocyte glutathione system plasma levels of 34 subjects with MCI, 45 subjects with AD and 28 age-matched control subjects. The results showed an increase in protein modification, a decrease in GSH levels and GSH/GSSG ratio in AD and MCI patients compared to age-matched control subjects (p<0.05). The present study shows that some peripheral markers of oxidative stress appear in MCI with a similar pattern to that observed in AD, which suggests that oxidative stress might represent a signal of the AD pathology. AD and MCI are biochemically equivalent. MCI does not necessarily need to progress to AD on a biochemical level.

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The spread of multidrug-resistant strains of fungus and the reduced number of drugs available, makes it necessary to discover new classes of antifungals and compounds that inhibit these resistant mechanisms. This has led to a search for therapeutic alternatives, particularly among medicinal plants and compounds isolated from them used for their empirically antifungal properties. In these natural sources, a series of molecules with antifungal activity against different strains of fungus have been found, which are of great importance to humans and plants. In this article, we review the main sources of molecules with antimycotic activity obtained from the natural environment.

The Baccharis genus is an important source of natural medicinal products. The information collected here is an attempt to cover the most recent developments in the ethnopharmacology, pharmacology and phytochemistry of this genus. This review describes its traditional and folkloric uses, phyto-constituents and pharmacological and toxicological reports of the prominent species of the genus Baccharis. Flavonoids and other phenolic compounds, diterpenoids and volatile constituents have been reported as the major phyto-constituents of the Baccharis species. Pharmacological studies are mainly based on the anti-inflammatory, antioxidant, antimicrobial and antifungal properties. The potential for development of leads from Baccharis genus continues to grow. The information summarized here is intended to serve as a reference tool to practitioners in the fields of ethnopharmacology and chemistry of natural products.

1H-NMR spectrometry was applied to the quantitative analysis of the bilobalide, ginkgolides A, B, and C in Ginkgo biloba leaves and six kinds of commercial Ginkgo products without any chromatographic purification. The experiment was performed by the analysis of each singlet H-12, which were well separated in the range of delta 6.0-7.0 in the (1)H-NMR spectrum. However, the H-12 protons of bilobalide and ginkgolides may have overlapped with H-6 or H-8 protons of the Ginkgo flavonoids. Therefore, the optimum (1)H-NMR solvent for the analysis of the compound was selected through the evaluation of solvent effects on the resolution of these signals from the compounds. Acetone-d(6)-benzene-d(6) (50 : 50) was found to be the best one among the solvents evaluated. The quantity of the compounds was calculated by the relative ratio of the intensity of each compound to the known amount of internal standard (25 microgram), phloroglucinol. This method allows rapid and simple quantitation of underivatized bilobalide and ginkgolides in 5 min without any pre-purification steps.

1 Andalusol, ent-6a,8a,18-trihydroxy-13(16),14-labdadiene, is a naturally occurring diterpene, isolated from Sideritis foetens (Lamiaceae). This compound exhibited therapeutic activity when evaluated in in vivo models of paw and ear in¯ammation (Navarro et al., 1997: Z. Naturforsch., 52, 844-849). The pharmacological eects of this diterpene have been analysed on the activation of the macrophage cell line J774 with lipopolysaccharide (LPS) and interferon-g (IFN-g). 2 Incubation of J774 macrophages with andalusol (0.1 ± 100 mM) inhibited the synthesis of nitrite caused by LPS (1 mg ml 71 ) in concentration and time-dependent manners. The maximal inhibition was observed when andalusol was added 30 min before LPS stimulation and decreased progressively as the interval between andalusol and LPS challenge increased up to 14 h. 3 Incubation of J774 cells with LPS resulted in the expression of NOS-2 protein (130 kDa) as identi®ed by Western blot analysis. The levels of this enzyme decreased signi®cantly in the presence of andalusol (IC 50 =10.5 mM), suggesting that this diterpene inhibited NOS-2 expression. 4 Andalusol inhibited nuclear factor kB activation, a transcription factor necessary for NOS-2 expression in response to LPS and IFN-g. This compound also inhibited the degradation of IkBa favouring the retention of the inactive NF-kB complexes in the cytosol. 5 Related compounds to andalusol but lacking the polyol groups were less eective inhibiting NOS-2 expression in LPS-activated macrophages. The present ®ndings provide a mechanism by which the anti-in¯ammatory properties of this diterpene could be mediated.

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