Tattooing breast cancers treated with neoadjuvant chemotherapy.

BACKGROUND: In breast carcinomas treated with neoadjuvant chemotherapy, intraoperative identification of residual tumors may be difficult. A well-tolerated, low-diffusion charcoal suspension has been designed to tattoo breast tumors. In this study, we investigated whether this tattooing technique is efficient for localizing the tumor after treatment with chemotherapy. METHODS: In a series of 109 patients with large breast tumors, a 4% or 10% charcoal suspension was injected at the time of the initial biopsy before preoperative chemotherapy. RESULTS: Tolerance was good. After three or four cycles of chemotherapy, 91 patients underwent conservative treatment, and the surgical specimen was examined intraoperatively. The charcoal was detected in 94% of the cases. The charcoal was seen in the nodule or at the periphery in the surgical specimen without any acute inflammatory reaction or diffusion. CONCLUSIONS: On the basis of these results, this micronized charcoal suspension at a defined granulometry and a concentration of 10% seems to be ideal for tattooing breast carcinomas over a period of 3 months in patients in whom neoadjuvant chemotherapy is planned.

Insulin-loaded W/O/W multiple emulsions: comparison of the performances of systems prepared with medium-chain-triglycerides and fish oil.

Insulin-loaded W/O/W multiple emulsions (ME) composed of medium-chain triglycerides have been shown to decrease the blood glucose level after oral administration to diabetic rats. Fish oil (very long-chain triglycerides) could be an alternative to medium-chain triglycerides because its chronic consumption has beneficial therapeutic effects. The aim of this work was twofold: to obtain stable fish oil containing ME, based on a formulation optimized in a previous work with low medium-chain triglycerides content, and to compare their characteristics to those of ME composed of medium-chain triglycerides. Due to the higher viscosity and surface tension of fish oil compared to medium-chain triglycerides, preparation of ME appeared difficult to achieve. However, a stable unloaded-ME with low fish oil content was formed, by adapting the emulsification process. The characteristics of unloaded fish oil ME were almost similar to those of medium-chain triglycerides ME. In contrast to medium-chain triglycerides ME, the introduction of insulin did not improve the elasticity and consequently the characteristics and stability of fish oil ME. Nevertheless, the insulin-loaded fish oil containing ME was shown to be stable for 6 weeks at 4 degrees C.

Cyclodextrins and emulsions.

This paper synthesises the literature on interactions between cyclodextrins (CD) and fatty acids and glycerides, and explains how these interactions allow the use of cyclodextrins to stabilise emulsions. An example of formulation with cyclodextrins is given which discusses the preparation of simple o/w emulsions, the addition of a model active ingredient, and the preparation of multiple emulsions in the absence of preformed surface active agents.

Effect of camphor/cyclodextrin complexation on the stability of O/W/O multiple emulsions.

Camphor (CA) encapsulation in oil/water/oil multiple emulsions prepared with cyclodextrin disturbs the emulsifier potential of alpha- and beta-natural cyclodextrins (CD). It was suggested that the size and geometrical fit between the CD cavity and CA could induce CD/CA complex formation in place of emulsifier formation leading to perturbation of emulsion stability. The complexation between CA and alpha-, beta- or gamma-CD in solution in the presence of oil phase are confirmed by phase-solubility diagrams, circular dichroism and 1H NMR. Furthermore, in order to mimic the emulsion system, CD/CA/soybean oil ternary dispersions were prepared to observe the complexation behavior of alpha-, beta- or gamma-CD/CA by circular dichroism. X-ray diffraction on emulsion samples prepared with alpha- and beta-CD confirms that the precipitates observed in emulsions are probably composed of crystals of CD/CA complexes. A preliminary study of the interaction between drug and CD before the formulation seems indispensable to prevent the risk of incompatibility.

Optimization of a thermally reversible W/O/W multiple emulsion for shear-induced drug release.

PURPOSE: The present work aimed at improvement of the formulation of a previously developed thermo-reversible W/O/W multiple emulsion by increasing the emulsion stability and reaching a higher fraction of an encapsulated drug released under shear. The emulsion was based on high molecular weight graft-copolymers of poly(acrylic acid) and Pluronic F127 as stabilizing agents. METHODS: Once a stable W/O/W thermo-reversible multiple emulsion was obtained via a fine-tuning of the formulation, rheological, granulometric and conductometric tests were performed to assess the thermo-reversible behavior and the fragmentation-release characteristics of the new W/O/W multiple emulsion. RESULTS: The emulsion exhibited a 10(3) fold increase in viscosity over a range of temperatures from 20 to 40 degrees C. At moderate shearing, a complete release of the marker encapsulated in the internal aqueous phase was observed (99.6%) at 35 degrees C, whereas only 30% was released at 20 degrees C. Under similar conditions at 35 degrees C, slightly more than 50% was released for the initial formula. CONCLUSION: Additionally, the ease of fabrication of the thermo-reversible W/O/W multiple emulsion combined with the complete release under shear at body temperature and the superior emulsion stability suggest numerous applications in the controlled release of drugs.