In response to a Hazard Notice by the Medical Devices Agency of the UK in 2000 regarding the Tril... more In response to a Hazard Notice by the Medical Devices Agency of the UK in 2000 regarding the Trilucent breast implant (TBI), an expert panel was convened to implement a research program to determine whether genotoxic compounds were formed in the soybean oil filler (SOF) of TBIs and whether these could be released to produce local or systemic genotoxicity. The panel established a research program involving six laboratories. The program recruited 47 patients who had received TBIs (9 patients had received silicone implants previously). A reference group (REBI) of 34 patients who had exchanged either silicone (17 patients) implants (REBI-E) or patients (17) who were to receive primary implantation augmentation with silicone (REBI-PIA), and who were included as needed to increase either the pre- or post-explantation sample number. Of the 17 REBI-E patients, 5 had silicone implants and 12 had saline implants previously (prior to the last exchange). Investigation was undertaken before and after replacement surgery in the TBI patients and before and after replacement or augmentation surgery in the REBI patients. The pre- to post-operative sample interval was 8-12 weeks. Pre-operative samples were collected within 7 days prior to the operation. Information on a variety of demographic and behavioral features was collected. Biochemical and biological endpoints relating to genotoxic lipid peroxidation (LPO) products potentially formed in the SOF, and released locally or distributed systemically, were measured. The SOF of explanted TBIs was found to have substantial levels of LPO products, particularly malondialdehyde (MDA), and low levels of trans-4-hydroxy-2-nonenal (HNE) not found in unused implants. Mutagenicity of the SOF was related to the levels of MDA. Capsules that formed around TBIs were microscopically similar to those of reference implants, but MDA-DNA adducts were observed in capsular macrophages and fibroblasts of only TBI capsules. These cell types are not progenitors of breast carcinoma (BCa) and the location of the implants precludes LPO products reaching the mammary epithelial cells which are progenitors of BCa. Blood levels of LPO products were not increased in TBI patients compared to REBI patients and did not change with explantation. In TBI patients, white blood cells did not show evidence of increased levels of LPO-related aldehyde DNA adducts. In conclusion, based on a number of measured parameters, there was no evident effect that would contribute to breast or systemic cancer risk in the TBI patients, and the recommended treatment of TBI patients involving explantation was judged appropriate.
Page 1. INTRODUCTION During inflammation, many cell types release reactive oxygen species (ROS) v... more Page 1. INTRODUCTION During inflammation, many cell types release reactive oxygen species (ROS) via the respiratory burst.1 These ROS are potent oxidants of LDL and its major protein, apolipoprotein B. Whilst native LDL ...
Vascular monocyte retention in the subintima is pivotal to the development of cardiovascular dise... more Vascular monocyte retention in the subintima is pivotal to the development of cardiovascular disease and is facilitated by up-regulation of adhesion molecules on monocytes/endothelial cells during oxidative stress. Epidemiological studies have shown that cardiovascular disease risk is inversely proportional to plasma levels of the dietary micronutrients, vitamin C and vitamin E (alpha-tocopherol). We have tested the hypothesis that alpha-tocopherol supplementation may alter endothelial/monocyte function and interaction in subjects with normal ascorbate levels (> 50 microM), as ascorbate has been shown to regenerate tocopherol from its oxidised tocopheroxyl radical form in vitro. Healthy male subjects received alpha-tocopherol supplements (400 IU RRR-alpha-tocopherol/day for 6 weeks) in a placebo-controlled, double-blind intervention study. There were no significant differences in monocyte CD11b expression, monocyte adhesion to endothelial cells, plasma C-reactive protein or sICAM-1 concentrations post-supplementation. There was no evidence for nuclear translocation of NF-kappaB in isolated resting monocytes, nor any effect of alpha-tocopherol supplementation. However, post-supplementation, sVCAM-1 levels were decreased in all subjects and sE-selectin levels were increased in the vitamin C-replete group only; a weak positive correlation was observed between sE-selectin and alpha-tocopherol concentration. In conclusion, alpha-tocopherol supplementation had little effect on cardiovascular disease risk factors in healthy subjects and the effects of tocopherol were not consistently affected by plasma vitamin C concentration.
ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the ... more ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the German Greens from 1979 to 1990. A prominent theoretician of the Greens, she broke ranks with the party on the issue of joining the Social Democrats in a governing coalition. She proposed, instead, that the Greens remain a radical parliamentary opposition force. Defeated in the All German parliamentary election of 1990, the Greens rejected Kelly's position and ultimately, in 1998, became the governing partner of the SPD. Ostracized and devastated by the 1990 defeat, Kelly spoke of "moving beyond the Greens." In 1992 she died under tragic circumstances. Her name sank into obscurity. Within our globalized era, however, Petra Kelly's ideas have particular salience. She represents the other Green who laid the foundations for a global political theory and for global political action.
ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the ... more ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the German Greens from 1979 to 1990. A prominent theoretician of the Greens, she broke ranks with the party on the issue of joining the Social Democrats in a governing coalition. She proposed, instead, that the Greens remain a radical parliamentary opposition force. Defeated in the All German parliamentary election of 1990, the Greens rejected Kelly's position and ultimately, in 1998, became the governing partner of the SPD. Ostracized and devastated by the 1990 defeat, Kelly spoke of "moving beyond the Greens." In 1992 she died under tragic circumstances. Her name sank into obscurity. Within our globalized era, however, Petra Kelly's ideas have particular salience. She represents the other Green who laid the foundations for a global political theory and for global political action.
In response to a Hazard Notice by the Medical Devices Agency of the UK in 2000 regarding the Tril... more In response to a Hazard Notice by the Medical Devices Agency of the UK in 2000 regarding the Trilucent breast implant (TBI), an expert panel was convened to implement a research program to determine whether genotoxic compounds were formed in the soybean oil filler (SOF) of TBIs and whether these could be released to produce local or systemic genotoxicity. The panel established a research program involving six laboratories. The program recruited 47 patients who had received TBIs (9 patients had received silicone implants previously). A reference group (REBI) of 34 patients who had exchanged either silicone (17 patients) implants (REBI-E) or patients (17) who were to receive primary implantation augmentation with silicone (REBI-PIA), and who were included as needed to increase either the pre- or post-explantation sample number. Of the 17 REBI-E patients, 5 had silicone implants and 12 had saline implants previously (prior to the last exchange). Investigation was undertaken before and after replacement surgery in the TBI patients and before and after replacement or augmentation surgery in the REBI patients. The pre- to post-operative sample interval was 8-12 weeks. Pre-operative samples were collected within 7 days prior to the operation. Information on a variety of demographic and behavioral features was collected. Biochemical and biological endpoints relating to genotoxic lipid peroxidation (LPO) products potentially formed in the SOF, and released locally or distributed systemically, were measured. The SOF of explanted TBIs was found to have substantial levels of LPO products, particularly malondialdehyde (MDA), and low levels of trans-4-hydroxy-2-nonenal (HNE) not found in unused implants. Mutagenicity of the SOF was related to the levels of MDA. Capsules that formed around TBIs were microscopically similar to those of reference implants, but MDA-DNA adducts were observed in capsular macrophages and fibroblasts of only TBI capsules. These cell types are not progenitors of breast carcinoma (BCa) and the location of the implants precludes LPO products reaching the mammary epithelial cells which are progenitors of BCa. Blood levels of LPO products were not increased in TBI patients compared to REBI patients and did not change with explantation. In TBI patients, white blood cells did not show evidence of increased levels of LPO-related aldehyde DNA adducts. In conclusion, based on a number of measured parameters, there was no evident effect that would contribute to breast or systemic cancer risk in the TBI patients, and the recommended treatment of TBI patients involving explantation was judged appropriate.
Page 1. INTRODUCTION During inflammation, many cell types release reactive oxygen species (ROS) v... more Page 1. INTRODUCTION During inflammation, many cell types release reactive oxygen species (ROS) via the respiratory burst.1 These ROS are potent oxidants of LDL and its major protein, apolipoprotein B. Whilst native LDL ...
Vascular monocyte retention in the subintima is pivotal to the development of cardiovascular dise... more Vascular monocyte retention in the subintima is pivotal to the development of cardiovascular disease and is facilitated by up-regulation of adhesion molecules on monocytes/endothelial cells during oxidative stress. Epidemiological studies have shown that cardiovascular disease risk is inversely proportional to plasma levels of the dietary micronutrients, vitamin C and vitamin E (alpha-tocopherol). We have tested the hypothesis that alpha-tocopherol supplementation may alter endothelial/monocyte function and interaction in subjects with normal ascorbate levels (> 50 microM), as ascorbate has been shown to regenerate tocopherol from its oxidised tocopheroxyl radical form in vitro. Healthy male subjects received alpha-tocopherol supplements (400 IU RRR-alpha-tocopherol/day for 6 weeks) in a placebo-controlled, double-blind intervention study. There were no significant differences in monocyte CD11b expression, monocyte adhesion to endothelial cells, plasma C-reactive protein or sICAM-1 concentrations post-supplementation. There was no evidence for nuclear translocation of NF-kappaB in isolated resting monocytes, nor any effect of alpha-tocopherol supplementation. However, post-supplementation, sVCAM-1 levels were decreased in all subjects and sE-selectin levels were increased in the vitamin C-replete group only; a weak positive correlation was observed between sE-selectin and alpha-tocopherol concentration. In conclusion, alpha-tocopherol supplementation had little effect on cardiovascular disease risk factors in healthy subjects and the effects of tocopherol were not consistently affected by plasma vitamin C concentration.
ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the ... more ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the German Greens from 1979 to 1990. A prominent theoretician of the Greens, she broke ranks with the party on the issue of joining the Social Democrats in a governing coalition. She proposed, instead, that the Greens remain a radical parliamentary opposition force. Defeated in the All German parliamentary election of 1990, the Greens rejected Kelly's position and ultimately, in 1998, became the governing partner of the SPD. Ostracized and devastated by the 1990 defeat, Kelly spoke of "moving beyond the Greens." In 1992 she died under tragic circumstances. Her name sank into obscurity. Within our globalized era, however, Petra Kelly's ideas have particular salience. She represents the other Green who laid the foundations for a global political theory and for global political action.
ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the ... more ABSTRACT Petra Kelly enjoyed celebrity status as cofounder and "leader" of the German Greens from 1979 to 1990. A prominent theoretician of the Greens, she broke ranks with the party on the issue of joining the Social Democrats in a governing coalition. She proposed, instead, that the Greens remain a radical parliamentary opposition force. Defeated in the All German parliamentary election of 1990, the Greens rejected Kelly's position and ultimately, in 1998, became the governing partner of the SPD. Ostracized and devastated by the 1990 defeat, Kelly spoke of "moving beyond the Greens." In 1992 she died under tragic circumstances. Her name sank into obscurity. Within our globalized era, however, Petra Kelly's ideas have particular salience. She represents the other Green who laid the foundations for a global political theory and for global political action.
Uploads
Papers by Ruth Bevan