Antimicrobial activity of Butyl acetate, Ethyl acetate and Isopropyl alcohol on undesirable microorganisms in cosmetic products.

OBJECTIVE: The microbiological contamination risk of a cosmetic product has to be assessed by the manufacturer, according to the composition, to determine whether microbiological testing is required. Certain ingredients in cosmetic formulations help to create an environment hostile towards microbial growth. In this study, the influence on microbial survival of some solvents used in nail varnishes was evaluated. The purpose of this study was two-fold. The first was to define the thresholds to be considered for the exemption of products from microbiological testing. The second was to assess the cross-contamination risk linked to the use on successive consumers of solvent-based products in beauty salons. METHODS: Strains of Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Candida albicans and Trichophyton rubrum were exposed to various concentrations of ethyl acetate, butyl acetate and isopropyl alcohol in culture medium to estimate their MIC (minimum inhibitory concentration). These strains are relevant to cosmetic products as they are associated with skin and nail infections. Mixtures of the three solvents, which are characteristic of nail varnish compositions, were also tested for their cidal activity. RESULTS: Ethyl and butyl acetates had a stronger impact than isopropyl alcohol: the MIC of ethyl and butyl acetate is ≤5% for all of the tested strains, whereas that of isopropyl alcohol is ≤10%. Various combinations of the three solvents tested showed a significant effect on both fungal and bacterial strains (greater than 3 log reduction in 15 min for the bacterial test strains and in 30 min for T. rubrum). CONCLUSION: Products containing more than 5% ethyl or butyl acetate or more than 10% isopropyl alcohol are hostile towards microbial growth. These products can therefore be considered as microbiologically low risk during both production and use, and so do not require microbiological testing (challenge test and end-product testing). Moreover, the nine tested mixtures of these three solvents - which are characteristic of nail varnish compositions - all have a high cidal activity on the tested strains within a short time. The risk of cross-contamination can therefore be considered as controlled when the nail varnishes are applied on successive clients in beauty salons.

Bactericidal activity of ammonia and monoethanolamine on Pseudomonas aeruginosa and Staphylococcus aureus strains of various origins.

OBJECTIVE: Microbiological risk of cosmetic products has to be assessed by the manufacturers to determine whether microbiological testing is required, according to the composition of a given product. The use of certain ingredients in cosmetic formulations will help to create a hostile environment towards microbial growth. In this study, the influence of some cosmetic ingredients on bacterial survival was evaluated. METHODS: Strains of Pseudomonas aeruginosa and Staphylococcus aureus, which are relevant to cosmetic products given their ability to cause skin infection, were exposed to various concentrations of ammonia or monoethanolamine in culture medium. Microbial strains obtained from collection, clinical or industrial sources were included to assess the possible influence of strain origin. RESULTS: Increased concentrations of ammonia or monoethanolamine led to faster and larger reductions in bacterial populations. Staphylococcus aureus proved being more resistant than P. aeruginosa, and ammonia had a stronger impact than monoethanolamine. Strain origin showed a marginal influence on survival. CONCLUSION: Concentrations higher than or equal to 0.5% (v/v) ammonia or 1% (v/v) monoethanolamine were able to completely inactivate bacterial populations (more than 5-log reduction) in just a few days.

Small molecule inhibitors of Apaf-1-related caspase- 3/-9 activation that control mitochondrial-dependent apoptosis.

Apoptosis is a biological process relevant to human disease states that is strongly regulated through protein-protein complex formation. These complexes represent interesting points of chemical intervention for the development of molecules that could modulate cellular apoptosis. The apoptosome is a holoenzyme multiprotein complex formed by cytochrome c-activated Apaf-1 (apoptotic protease-activating factor), dATP and procaspase-9 that link mitochondria disfunction with activation of the effector caspases and in turn is of interest for the development of apoptotic modulators. In the present study we describe the identification of compounds that inhibit the apoptosome-mediated activation of procaspase-9 from the screening of a diversity-oriented chemical library. The active compounds rescued from the library were chemically optimised to obtain molecules that bind to both recombinant and human endogenous Apaf-1 in a cytochrome c-noncompetitive mechanism that inhibits the recruitment of procaspase-9 by the apoptosome. These newly identified Apaf-1 ligands decrease the apoptotic phenotype in mitochondrial-mediated models of cellular apoptosis.

Antitumor effect of B16 melanoma cells genetically modified with the angiogenesis inhibitor rnasin.

The growth of new blood vessels is an essential condition for the development of tumors with a diameter greater than 1-2 mm and also for their metastatic dissemination. RNasin, the placental ribonuclease inhibitor, is known to have antiangiogenic activity through the inhibition of angiogenin and basic fibroblast growth factor. Nevertheless, the administration of the recombinant form of a protein poses several limitations; as a result, we have studied the antitumor effect of RNasin in a murine gene therapy model. RNasin cDNA was subcloned into the pcDNA3 expression vector, and the resulting recombinant plasmid was used to transfect the B16 murine melanoma cell line. An RNasin inverted construction was used as control. Mice intravenously injected with clones expressing RNasin showed a significant inhibition of tumor metastatic progression with respect to control groups (P<.001) and survived longer (P<.001). Tissue sections from RNasin-expressing cell tumors showed a lower number of blood vessels when compared to tissue sections from mice lungs that had been inoculated with control cell lines. The results of these experiments show that the genetic modification of tumor cells with RNasin cDNA yields a significant antitumor effect, and suggest that this effect is at least partially the result of angiogenesis inhibition.

A model for enhancing Internet medical document retrieval with "medical core metadata".

OBJECTIVE: Finding documents on the World Wide Web relevant to a specific medical information need can be difficult. The goal of this work is to define a set of document content description tags, or metadata encodings, that can be used to promote disciplined search access to Internet medical documents. DESIGN: The authors based their approach on a proposed metadata standard, the Dublin Core Metadata Element Set, which has recently been submitted to the Internet Engineering Task Force. Their model also incorporates the National Library of Medicine's Medical Subject Headings (MeSH) vocabulary and MEDLINE-type content descriptions. RESULTS: The model defines a medical core metadata set that can be used to describe the metadata for a wide variety of Internet documents. CONCLUSIONS: The authors propose that their medical core metadata set be used to assign metadata to medical documents to facilitate document retrieval by Internet search engines.