1,3 Butadiene (BD) is an industrial intermediate used primarily in product manufacturing with the greatest exposure potential via inhalation. BD was evaluated for reproductive and developmental effects in a Good Laboratory Practice (GLP)-compliant, extended OECD 421 guideline study (completed 2003). Twelve-week old rats (12/sex/dose) were exposed via whole-body inhalation to BD vapor (0, 300, 1500, 6000 ppm) for 6 h/day, 7 days/week, starting 14 days prior to mating through the day prior to euthanasia (total exposures: 83-84 days for F0 males 60-70 days for F0 females).
View Article and Find Full Text PDFAirway hyperreactivity (AHR) measurements and bronchoalveolar lavage (BAL) fluid sampling are essential to experimental asthma models, but repeated procedures to obtain such measurements in the same animal are generally not feasible. Here, we demonstrate protocols for obtaining from mice repeated measurements of AHR and bronchoalveolar lavage fluid samples. Mice were challenged intranasally seven times over 14 days with a potent allergen or sham treated.
View Article and Find Full Text PDFThe innate immune response of airway epithelial cells to airborne allergens initiates the development of T cell responses that are central to allergic inflammation. Although proteinase allergens induce the expression of interleukin 25, we show here that epithelial matrix metalloproteinase 7 (MMP7) was expressed during asthma and was required for the maximum activity of interleukin 25 in promoting the differentiation of T helper type 2 cells. Allergen-challenged Mmp7(-/-) mice had less airway hyper-reactivity and production of allergic inflammatory cytokines and higher expression of retinal dehydrogenase 1.
View Article and Find Full Text PDFCell Biol Toxicol
August 2009
Boron (B) is a developmental and reproductive toxin. It is also essential for some organisms. Plants use uptake and efflux transport proteins to maintain homeostasis, and in humans, boron has been reported to reduce prostate cancer.
View Article and Find Full Text PDFCancer Causes Control
February 2007
Objective: To determine: (1) the correlation of prostate cancer incidence and mortality with groundwater boron and selenium concentrations; and (2) the impact of boron on prostate cancer cell proliferation during co-treatment with alternative chemo-preventative agents, along with boron pre-treatment effects on cell sensitivity to ionizing radiation.
Methods: For regression analysis, data on prostate cancer incidence and mortality were obtained from the Texas Cancer Registry, while groundwater boron and selenium concentrations were derived from the Texas Water Development Board. Cultured DU-145 prostate cancer cells were used to assess the impact of boric acid on cell proliferation when applied in combination with selenomethionine and genistein, or preceding radiation exposure.
The role of boron in biology includes coordinated regulation of gene expression in mixed bacterial populations and the growth and proliferation of higher plants and lower animals. Here we report that boric acid, the dominant form of boron in plasma, inhibits the proliferation of prostate cancer cell lines, DU-145 and LNCaP, in a dose-dependent manner. Non-tumorigenic prostate cell lines, PWR-1E and RWPE-1, and the cancer line PC-3 were also inhibited, but required concentrations higher than observed human blood levels.
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