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Premature infants who receive supplemental oxygen at a pressure higher than 80 millimeters of mercury (mm Hg) may have a greater risk of developing retinopathy of prematurity than those who are exposed to lower pressures of oxygen. Retinopathy of prematurity is a disease that affects the retina of the developing eye, and can cause visual impairment and blindness. Of 101 premature infants weighing between 500 and 1,300 grams (g) who received supplemental oxygen during the first four weeks after birth, 52 (51%) developed retinopathy of prematurity. Nineteen of 22 infants who weighed less than 900 g (86%) and 33 of 79 infants who weighed 900 g or more (42%) developed retinopathy of prematurity. Seventy-five percent of the infants who were exposed to an oxygen pressure higher than 80 mm Hg for more than 12 hours developed retinopathy of prematurity, compared to 26% of those who were exposed to this pressure for less than 12 hours. The length of time infants were exposed to oxygen at more than 80 mm Hg was associated with the severity of the disease, especially during the second to fourth week of life.

Abstract Background While increased urokinase-type plasminogen activator (uPA) expression in breast cancer tissue is directly associated with poor prognosis, recent evidence suggests that uPA overexpression may suppress tumor growth and prolong survival. Celecoxib has been shown to have antiangiogenic and antiproliferative properties. We sought to determine if uPA, PA inhibitor (PAI)-1 and prostaglandin (PG)E2 expression in nipple aspirate fluid (NAF) and uPA and PGE2 expression in plasma were altered by celecoxib dose and concentration in women at increased breast cancer risk. Methods NAF and plasma samples were collected in women at increased breast cancer risk before and 2 weeks after taking celecoxib 200 or 400 mg twice daily (bid). uPA, PAI-1 and PGE2 were measured before and after intervention. Results Celecoxib concentrations trended higher in women taking 400 mg (median 1025.0 ng/mL) compared to 200 mg bid (median 227.3 ng/mL), and in post- (534.6 ng/mL) compared to premenopausal (227.3 ng/mL) women. In postmenopausal women treated with the higher (400 mg bid) celecoxib dose, uPA concentrations increased, while PAI-1 and PGE2 decreased. In women taking the higher dose, both PAI-1 (r = -.97, p = .0048) and PGE2 (r = -.69, p = .019) in NAF and uPA in plasma (r = .45, p = .023) were correlated with celecoxib concentrations. Conclusion Celecoxib concentrations after treatment correlate inversely with the change in PAI-1 and PGE2 in the breast and directly with the change in uPA in the circulation. uPA upregulation, in concert with PAI-1 and PGE2 downregulation, may have a cancer preventive effect.

Abstract Background Epidemiologic studies suggest that long term low dose celecoxib use significantly lowers breast cancer risk. We previously demonstrated that 400 mg celecoxib taken twice daily for 2 weeks lowered circulating plasma and breast nipple aspirate fluid (NAF) prostaglandin (PG)E2 concentrations in post- but not premenopausal high risk women. We hypothesized that circulating concentrations of celecoxib influenced PGE2 response, and that plasma levels of the drug are influenced by menopausal status. To address these hypotheses, the aims of the study were to determine: 1) if circulating plasma concentrations of celecoxib correlated with the change in plasma or NAF PGE2 concentrations from baseline to end of treatment, and 2) whether menopausal status influenced circulating levels of celecoxib. Methods Matched NAF and plasma were collected from 46 high risk women who were administered celecoxib twice daily for two weeks, 20 subjects receiving 200 mg and 26 subjects 400 mg of the agent. NAF and plasma samples were collected before and 2 weeks after taking celecoxib. Results In women taking 400 mg bid celecoxib, plasma concentrations of the agent correlated inversely with the change in NAF PGE2 levels from pre- to posttreatment. Nonsignificant trends toward higher celecoxib levels were observed in post- compared to premenopausal women. There was a significant decrease in NAF but not plasma PGE2 concentrations in postmenopausal women who took 400 mg celecoxib (p = 0.03). Conclusion In high risk women taking 400 mg celecoxib twice daily, plasma concentrations of celecoxib correlated with downregulation of PGE2 production by breast tissue. Strategies synergistic with celecoxib to downregulate PGE2 are of interest, in order to minimize the celecoxib dose required to have an effect.