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Microemulsions (MEs) were designed by an innovative rational development, characterized, and used to load up to 20mM of Tamoxifen citrate (TMX). They were made with acceptable and well-characterized excipients for all the routes of administration. Some of their properties, such as nanometric mean size and long stability shelf life, make them interesting drug delivery systems. The results obtained after the in vitro inhibition of estradiol-induced proliferation in MCF-7 breast cancer cells demonstrated a significant effect in cell growth. A decreasing of at least 90% in viable cells was shown after the incubation with MEs containing 20mM of TMX. Besides, two compositions which loaded 10mMof drug showed a cytotoxic effect higher than 70%. These results encourage the evaluation of alternative protocols for this drug administration, not only for estrogen receptor (ER) positive tumors, but also for ER negative. [ABSTRACT FROM AUTHOR]

Microspheres of Bacillus subtilis were prepared using sodium alginate. Some typical properties of microencapsulated systems, such as microorganism content, particle size, and germination time, were studied. Calcium alginate microspheres were obtained by the emulsification method, dripping into a solution of calcium salt. The conditions of the preparation steps were very seft to produce calcium alginate microspheres containing cells with no apparent changes in general biological properties. The hydrogel matrix provides protection without preventing communication with the surrounding medium. [ABSTRACT FROM AUTHOR]

Seminal hyperviscosity is generally thought to reveal genitourinary infection. The aim of the present work was to study this hypothesis. A total of 65 semen samples were obtained from males presenting for infertility screening. The samples were evaluated according to WHO criteria and microbiologically investigated, including culturing for Mycoplasma hominis and Ureaplasma urealyticum, and microscopic observation of Chlamydia trachomatis by a direct fluorescence assay. Determination of local antisperm antibodies was performed. Semen was categorized according to consistency: normal (n = 31) and high (n = 34). No difference was recorded either in the number of positive cultures, or in the number of species found in each sample. The number of white blood cells and the percentage of antibody-bound sperm showed no difference in the groups under study. There was no association between seminal hyperviscosity, positivity in semen cultures, number of species isolated in semen cultures, leukospermia, or presence of sperm antibodies. Further studies should be performed considering the evolution of the genital-infected patients to clarify the etiology of the hyperviscosity. [ABSTRACT FROM AUTHOR]

The effectiveness of any cosmetic product containing a functional ingredient is determined by the skin delivery of the active molecule, which is influenced by the type of carrier and the molecule itself. Furthermore, the functional ingredient should be stable in the formulation. The purpose of this paper is to study the stability of lipoic acid in the presence of vitamins A (as palmitate) and E (as acetate) in semisolids for cosmetic use. The systems formulated were studied in regard to their aspect, pH, stability under centrifugation and rheological behavior. The chemical analyses of lipoic acid and vitamins A and E were carried out by HPLC after studying the specificity of the method employed in each case. The quantitation of the active principles was performed by HPLC with C18 (5 μm) columns. The mobile phase was methanol for the vitamins, with spectrophotometric detection at 325 nm for vitamin A and 230 nm for vitamin E. The mobile phase for lipoic acid was methanol : water (80 : 20) and phosphoric acid at pH 3.0, with spectrophotometric detection at 332 nm. All systems were stable to centrifugation, and no significant modification of rheological behavior was observed in relation to the base emulsion used as control. The chemical studies performed indicated that although lipoic acid is not very stable in these formulations, the presence of vitamin A favors its chemical stability. [ABSTRACT FROM AUTHOR]