Quantitative risk assessment of contact sensitization: clinical data to assess utility of the model.

Background: Contact hypersensitivity quantitative risk assessment (QRA) for fragrance ingredients is being used to establish new international standards for all fragrance ingredients that are potential skin sensitizers.

Objective: The objective was to evaluate the retrospective clinical data on three fragrance ingredients in order to provide a practical assessment of the predictive value of the QRA approach. It is important to have data to assess that the methodology provides a robust approach for primary prevention of contact sensitization induction for fragrance ingredients identified as potential sensitizers.

Raising gestational choline intake alters gene expression in DMBA-evoked mammary tumors and prolongs survival.

Choline is an essential nutrient that serves as a donor of metabolic methyl groups used during gestation to establish the epigenetic DNA methylation patterns that modulate tissue-specific gene expression. Because the mammary gland begins its development prenatally, we hypothesized that choline availability in utero may affect the gland's susceptibility to cancer. During gestational days 11-17, pregnant rats were fed a control, choline-supplemented, or choline-deficient diet (8, 36, and 0 mmol/kg of choline, respectively).

Green tea polyphenols reverse cooperation between c-Rel and CK2 that induces the aryl hydrocarbon receptor, slug, and an invasive phenotype.

Exposure to and bioaccumulation of lipophilic environmental pollutants, such as polycyclic aromatic hydrocarbons (PAHs), has been implicated in breast cancer. Treatment of female rats with the prototypic xenobiotic PAH 7,12-dimethylbenz(a)anthracene (DMBA) induces mammary tumors with an invasive phenotype. Here, we show that green tea prevents or reverses loss of the epithelial marker E-cadherin on the surface of DMBA-induced in situ cancers.

Medical hyperspectral imaging to facilitate residual tumor identification during surgery.

Introduction: Adequate evaluation of breast tumor resection at surgery continues to be an important issue in surgical care, as over 30% of postoperative tumors recur locally unless radiation is used to destroy remaining tumor cells in the field. Medical Hyperspectral Imaging (MHSI) delivers near-real time images of biomarkers in tissue, providing an assessment of pathophysiology and the potential to distinguish different tissues based on spectral characteristics.

Methods: We have used an experimental DMBA-induced rat breast tumor model to examine the intraoperative utility of MHSI, in distinguishing tumor from normal breast and other tissues.

Increased expression of MDM2, cyclin D1, and p27Kip1 in carcinogen-induced rat mammary tumors.

It is thought that environmental pollutants, such as polycyclic aromatic hydrocarbons (PAH), contribute to human breast tumorigenesis, yet their roles remain incompletely elucidated. The prototypical PAH 7,12-dimethylbenz(alpha)anthracene (DMBA) specifically and effectively induces mammary tumor formation in rodent models. In an attempt to explore the molecular mechanisms by which PAH initiates and promotes mammary tumorigenesis, we examined the expression of several cell cycle regulators in rat mammary tumors induced by DMBA.

What's in store for medical students? Awareness and utilization of expert nutrition guidelines among medical school preceptors.

Background: Instruction of physicians and other health professionals in medical nutrition sciences is among the expert recommendations to promote population health and reduce risks for cancer and other major causes of morbidity and mortality in the population. However, formal training in nutrition in United States medical schools is still lacking compared to the gains in basic and applied medical nutrition sciences. We sought to understand the awareness and current utilization of expert nutrition recommendations and practice guidelines among medical student faculty preceptors.

The safety assessment of fragrance materials.

Safety evaluation of the large number of diverse chemicals used as fragrance ingredients follows a systematic prioritization of data generation and analysis, consideration of exposure and critical analysis of the quality of the available information. In prior publications the research priorities used by the Research Institute for Fragrance Materials (RIFM), and the methods of exposure estimation used by industry have been summarized. This paper provides details of the approach used by the RIFM Expert Panel (REXPAN), to examine the dermal effects, systemic toxicity and environmental consequences of the use of and exposure to fragrance materials, which allow a reliable determination of safe use under intended conditions.