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Barbara Mcknight - One of the best experts on this subject based on the ideXlab platform.
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risk of endometrial cancer in relation to use of oestrogen combined with cyclic Progestagen therapy in postmenopausal women
The Lancet, 1997Co-Authors: Shirley A A Beresford, Lynda F Voigt, Barbara Mcknight, Noel S WeissAbstract:Summary Background Postmenopausal oestrogen therapy reduces the risk of osteoporosis and cardiovascular diseases but is associated with an increased risk of endometrial cancer. We have assessed the impact of a regimen of oestrogen with cyclic Progestagen on risk of endometrial cancer for postmenopausal women. Methods We did a population-based case-control study of women aged 45–74 years in western Washington State, USA Cases were identified from a regional cancer registry as having histologically confirmed endometrial cancer during 1985–91. 832 (72%) of 1154 eligible cases completed interviews. Controls were identified by random digit dialling, screened for intact uterus, frequency matched for age and county, and randomly assigned a reference date within 1985–91. Interviews with 1114 (73%) of 1526 eligible controls were done. The women provided information about use of hormone replacement therapy, and reproductive and medical history before diagnosis date (cases) orreference date (controls). Findings Relative to women who had never used hormones (for >6 months), women who had taken unopposed oestrogen had a four-fold increase (95% CI 3·1–5·1) in risk of endometrial cancer. Women who used a combined therapy of oestrogen with cyclic Progestagen (eg, medroxyprogesterone acetate) had a relative risk of 1·4 (1·0–1·9). Among women with fewer than 10 days of added Progestagen per month, the relative risk was 3·1 (1·7–5·7), whereas that for women with 10–21 days of added Progestagen was 1·3 (0·8–2·2). The use of these combined regimens for 5 or more years was associated with risks of 3·7 (1·7–8·2) and 2·5 (1·1–5·5), respectively, relative to non-users of hormones. Interpretation Postmenopausal women who use combined therapy of oestrogen with cyclic Progestagen on a long-term basis have an increased risk of endometrial cancer compared with those who are not on hormone replacement, even when Progestagen is added for 10 or more days per month. This increase is much smaller than that associated with unopposed oestrogen, but needs to be confirmed.
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Progestagen supplementation of exogenous oestrogens and risk of endometrial cancer
The Lancet, 1991Co-Authors: Lynda F Voigt, N S Weiss, Janet R Daling, Barbara Mcknight, G Van BelleAbstract:Abstract The favourable effects of exogenous Progestagen on the endometrium are well known, but have not been adequately quantified with respect to endometrial cancer. The benefits of Progestagen need to be weighted against its possible untoward effects on the risk of breast cancer and cardiovascular disease. A population-based case-control study of endometrial cancer was undertaken to evaluate the benefits of Progestagen use. 158 incident cases were identified between 1985 and 1987 among women aged 40-64 years who were residents of King County, Washington. Detailed interviews were conducted and the responses were compared with those of 182 controls selected by random telephone digit dialling. The risk of endometrial cancer among women who had used unopposed oestrogen for more than 3 years was over five times that of women who had used no hormones (relative risk [RR] 5·7, 95% confidence interval [Cl] 2·5-12·8), whereas those who had also used a Progestagen for at least six months of that time had an RR of only 1·6 (95% Cl 0·6-3·9). The RR differed according to days per month that Progestagen was used: 2·4 (0·6-9·3) for Progestagen use of less than 10 days per month versus 1·1 (0·4-3·6) for use of 10 or more days per month. These results provide additional evidence that the use of Progestagen for 10 or more days per cycle can reduce the excess risk of endometrial cancer associated with long-term postmenopausal oestrogen use.
Sebastien Sauve - One of the best experts on this subject based on the ideXlab platform.
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Degradation of Progestagens by oxidation with potassium permanganate in wastewater effluents
Chemistry Central Journal, 2013Co-Authors: Paul B Fayad, Romain Broseus, Arash Zamyadi, Michele Prevost, Sebastien SauveAbstract:BackgroundThis study investigated the oxidation of selected Progestagenic steroid hormones by potassium permanganate at pH 6.0 and 8.0 in ultrapure water and wastewater effluents, using bench-scale assays. Second order rate constants for the reaction of potassium permanganate with Progestagens (levonorgestrel, medroxyprogesterone, norethindrone and progesterone) was determined as a function of pH, presence of natural organic matter and temperature. This work also illustrates the advantages of using a novel analytical method, the laser diode thermal desorption (LDTD-APCI) interface coupled to tandem mass spectrometry apparatus, allowing for the quick determination of oxidation rate constants and increasing sample throughput.ResultsThe second-order rate constants for Progestagens with permanganate determined in bench-scale experiments ranged from 23 to 368 M^-1 sec^-1 in both wastewater and ultrapure waters with pH values of 6.0 and 8.0. Two pairs of Progestagens exhibited similar reaction rate constants, i.e. progesterone and medroxyprogesterone (23 to 80 M^-1 sec^-1 in ultrapure water and 26 to 149 M^-1 sec^-1 in wastewaters, at pH 6.0 and 8.0) and levonorgestrel and norethindrone (179 to 224 M^-1 sec^-1 in ultrapure water and 180 to 368 M^-1 sec^-1 in wastewaters, at pH 6.0 and 8.0). The presence of dissolved natural organic matter and the pH conditions improved the oxidation rate constants for Progestagens with potassium permanganate only at alkaline pH. Reaction rates measured in Milli-Q water could therefore be used to provide conservative estimates for the oxidation rates of the four selected Progestagens in wastewaters when exposed to potassium permanganate. The Progestagen removal efficiencies was lower for progesterone and medroxyprogesterone (48 to 87 %) than for levonorgestrel and norethindrone (78 to 97%) in Milli-Q and wastewaters at pH 6.0-8.2 using potassium permanganate dosages of 1 to 5 mg L^-1 after contact times of 10 to 60 min.ConclusionThis work presents the first results on the permanganate-promoted oxidation of Progestagens, as a function of pH, temperature as well as NOM. Progestagen concentrations used to determine rate constants were analyzed using an ultrafast laser diode thermal desorption interface coupled to tandem mass spectrometry for the analysis of water sample for Progestagens.
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Degradation of Progestagens by oxidation with potassium permanganate in wastewater effluents
Chemistry Central Journal, 2013Co-Authors: Paul B Fayad, Romain Broseus, Arash Zamyadi, Michele Prevost, Sebastien SauveAbstract:This study investigated the oxidation of selected Progestagenic steroid hormones by potassium permanganate at pH 6.0 and 8.0 in ultrapure water and wastewater effluents, using bench-scale assays. Second order rate constants for the reaction of potassium permanganate with Progestagens (levonorgestrel, medroxyprogesterone, norethindrone and progesterone) was determined as a function of pH, presence of natural organic matter and temperature. This work also illustrates the advantages of using a novel analytical method, the laser diode thermal desorption (LDTD-APCI) interface coupled to tandem mass spectrometry apparatus, allowing for the quick determination of oxidation rate constants and increasing sample throughput. The second-order rate constants for Progestagens with permanganate determined in bench-scale experiments ranged from 23 to 368 M-1 sec-1 in both wastewater and ultrapure waters with pH values of 6.0 and 8.0. Two pairs of Progestagens exhibited similar reaction rate constants, i.e. progesterone and medroxyprogesterone (23 to 80 M-1 sec-1 in ultrapure water and 26 to 149 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0) and levonorgestrel and norethindrone (179 to 224 M-1 sec-1 in ultrapure water and 180 to 368 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0). The presence of dissolved natural organic matter and the pH conditions improved the oxidation rate constants for Progestagens with potassium permanganate only at alkaline pH. Reaction rates measured in Milli-Q water could therefore be used to provide conservative estimates for the oxidation rates of the four selected Progestagens in wastewaters when exposed to potassium permanganate. The Progestagen removal efficiencies was lower for progesterone and medroxyprogesterone (48 to 87 %) than for levonorgestrel and norethindrone (78 to 97%) in Milli-Q and wastewaters at pH 6.0-8.2 using potassium permanganate dosages of 1 to 5 mg L-1 after contact times of 10 to 60 min. This work presents the first results on the permanganate-promoted oxidation of Progestagens, as a function of pH, temperature as well as NOM. Progestagen concentrations used to determine rate constants were analyzed using an ultrafast laser diode thermal desorption interface coupled to tandem mass spectrometry for the analysis of water sample for Progestagens.
Lynda F Voigt - One of the best experts on this subject based on the ideXlab platform.
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risk of endometrial cancer in relation to use of oestrogen combined with cyclic Progestagen therapy in postmenopausal women
The Lancet, 1997Co-Authors: Shirley A A Beresford, Lynda F Voigt, Barbara Mcknight, Noel S WeissAbstract:Summary Background Postmenopausal oestrogen therapy reduces the risk of osteoporosis and cardiovascular diseases but is associated with an increased risk of endometrial cancer. We have assessed the impact of a regimen of oestrogen with cyclic Progestagen on risk of endometrial cancer for postmenopausal women. Methods We did a population-based case-control study of women aged 45–74 years in western Washington State, USA Cases were identified from a regional cancer registry as having histologically confirmed endometrial cancer during 1985–91. 832 (72%) of 1154 eligible cases completed interviews. Controls were identified by random digit dialling, screened for intact uterus, frequency matched for age and county, and randomly assigned a reference date within 1985–91. Interviews with 1114 (73%) of 1526 eligible controls were done. The women provided information about use of hormone replacement therapy, and reproductive and medical history before diagnosis date (cases) orreference date (controls). Findings Relative to women who had never used hormones (for >6 months), women who had taken unopposed oestrogen had a four-fold increase (95% CI 3·1–5·1) in risk of endometrial cancer. Women who used a combined therapy of oestrogen with cyclic Progestagen (eg, medroxyprogesterone acetate) had a relative risk of 1·4 (1·0–1·9). Among women with fewer than 10 days of added Progestagen per month, the relative risk was 3·1 (1·7–5·7), whereas that for women with 10–21 days of added Progestagen was 1·3 (0·8–2·2). The use of these combined regimens for 5 or more years was associated with risks of 3·7 (1·7–8·2) and 2·5 (1·1–5·5), respectively, relative to non-users of hormones. Interpretation Postmenopausal women who use combined therapy of oestrogen with cyclic Progestagen on a long-term basis have an increased risk of endometrial cancer compared with those who are not on hormone replacement, even when Progestagen is added for 10 or more days per month. This increase is much smaller than that associated with unopposed oestrogen, but needs to be confirmed.
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Progestagen supplementation of exogenous oestrogens and risk of endometrial cancer
The Lancet, 1991Co-Authors: Lynda F Voigt, N S Weiss, Janet R Daling, Barbara Mcknight, G Van BelleAbstract:Abstract The favourable effects of exogenous Progestagen on the endometrium are well known, but have not been adequately quantified with respect to endometrial cancer. The benefits of Progestagen need to be weighted against its possible untoward effects on the risk of breast cancer and cardiovascular disease. A population-based case-control study of endometrial cancer was undertaken to evaluate the benefits of Progestagen use. 158 incident cases were identified between 1985 and 1987 among women aged 40-64 years who were residents of King County, Washington. Detailed interviews were conducted and the responses were compared with those of 182 controls selected by random telephone digit dialling. The risk of endometrial cancer among women who had used unopposed oestrogen for more than 3 years was over five times that of women who had used no hormones (relative risk [RR] 5·7, 95% confidence interval [Cl] 2·5-12·8), whereas those who had also used a Progestagen for at least six months of that time had an RR of only 1·6 (95% Cl 0·6-3·9). The RR differed according to days per month that Progestagen was used: 2·4 (0·6-9·3) for Progestagen use of less than 10 days per month versus 1·1 (0·4-3·6) for use of 10 or more days per month. These results provide additional evidence that the use of Progestagen for 10 or more days per cycle can reduce the excess risk of endometrial cancer associated with long-term postmenopausal oestrogen use.
Paul B Fayad - One of the best experts on this subject based on the ideXlab platform.
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Degradation of Progestagens by oxidation with potassium permanganate in wastewater effluents
Chemistry Central Journal, 2013Co-Authors: Paul B Fayad, Romain Broseus, Arash Zamyadi, Michele Prevost, Sebastien SauveAbstract:BackgroundThis study investigated the oxidation of selected Progestagenic steroid hormones by potassium permanganate at pH 6.0 and 8.0 in ultrapure water and wastewater effluents, using bench-scale assays. Second order rate constants for the reaction of potassium permanganate with Progestagens (levonorgestrel, medroxyprogesterone, norethindrone and progesterone) was determined as a function of pH, presence of natural organic matter and temperature. This work also illustrates the advantages of using a novel analytical method, the laser diode thermal desorption (LDTD-APCI) interface coupled to tandem mass spectrometry apparatus, allowing for the quick determination of oxidation rate constants and increasing sample throughput.ResultsThe second-order rate constants for Progestagens with permanganate determined in bench-scale experiments ranged from 23 to 368 M^-1 sec^-1 in both wastewater and ultrapure waters with pH values of 6.0 and 8.0. Two pairs of Progestagens exhibited similar reaction rate constants, i.e. progesterone and medroxyprogesterone (23 to 80 M^-1 sec^-1 in ultrapure water and 26 to 149 M^-1 sec^-1 in wastewaters, at pH 6.0 and 8.0) and levonorgestrel and norethindrone (179 to 224 M^-1 sec^-1 in ultrapure water and 180 to 368 M^-1 sec^-1 in wastewaters, at pH 6.0 and 8.0). The presence of dissolved natural organic matter and the pH conditions improved the oxidation rate constants for Progestagens with potassium permanganate only at alkaline pH. Reaction rates measured in Milli-Q water could therefore be used to provide conservative estimates for the oxidation rates of the four selected Progestagens in wastewaters when exposed to potassium permanganate. The Progestagen removal efficiencies was lower for progesterone and medroxyprogesterone (48 to 87 %) than for levonorgestrel and norethindrone (78 to 97%) in Milli-Q and wastewaters at pH 6.0-8.2 using potassium permanganate dosages of 1 to 5 mg L^-1 after contact times of 10 to 60 min.ConclusionThis work presents the first results on the permanganate-promoted oxidation of Progestagens, as a function of pH, temperature as well as NOM. Progestagen concentrations used to determine rate constants were analyzed using an ultrafast laser diode thermal desorption interface coupled to tandem mass spectrometry for the analysis of water sample for Progestagens.
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Degradation of Progestagens by oxidation with potassium permanganate in wastewater effluents
Chemistry Central Journal, 2013Co-Authors: Paul B Fayad, Romain Broseus, Arash Zamyadi, Michele Prevost, Sebastien SauveAbstract:This study investigated the oxidation of selected Progestagenic steroid hormones by potassium permanganate at pH 6.0 and 8.0 in ultrapure water and wastewater effluents, using bench-scale assays. Second order rate constants for the reaction of potassium permanganate with Progestagens (levonorgestrel, medroxyprogesterone, norethindrone and progesterone) was determined as a function of pH, presence of natural organic matter and temperature. This work also illustrates the advantages of using a novel analytical method, the laser diode thermal desorption (LDTD-APCI) interface coupled to tandem mass spectrometry apparatus, allowing for the quick determination of oxidation rate constants and increasing sample throughput. The second-order rate constants for Progestagens with permanganate determined in bench-scale experiments ranged from 23 to 368 M-1 sec-1 in both wastewater and ultrapure waters with pH values of 6.0 and 8.0. Two pairs of Progestagens exhibited similar reaction rate constants, i.e. progesterone and medroxyprogesterone (23 to 80 M-1 sec-1 in ultrapure water and 26 to 149 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0) and levonorgestrel and norethindrone (179 to 224 M-1 sec-1 in ultrapure water and 180 to 368 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0). The presence of dissolved natural organic matter and the pH conditions improved the oxidation rate constants for Progestagens with potassium permanganate only at alkaline pH. Reaction rates measured in Milli-Q water could therefore be used to provide conservative estimates for the oxidation rates of the four selected Progestagens in wastewaters when exposed to potassium permanganate. The Progestagen removal efficiencies was lower for progesterone and medroxyprogesterone (48 to 87 %) than for levonorgestrel and norethindrone (78 to 97%) in Milli-Q and wastewaters at pH 6.0-8.2 using potassium permanganate dosages of 1 to 5 mg L-1 after contact times of 10 to 60 min. This work presents the first results on the permanganate-promoted oxidation of Progestagens, as a function of pH, temperature as well as NOM. Progestagen concentrations used to determine rate constants were analyzed using an ultrafast laser diode thermal desorption interface coupled to tandem mass spectrometry for the analysis of water sample for Progestagens.
G Van Belle - One of the best experts on this subject based on the ideXlab platform.
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Progestagen supplementation of exogenous oestrogens and risk of endometrial cancer
The Lancet, 1991Co-Authors: Lynda F Voigt, N S Weiss, Janet R Daling, Barbara Mcknight, G Van BelleAbstract:Abstract The favourable effects of exogenous Progestagen on the endometrium are well known, but have not been adequately quantified with respect to endometrial cancer. The benefits of Progestagen need to be weighted against its possible untoward effects on the risk of breast cancer and cardiovascular disease. A population-based case-control study of endometrial cancer was undertaken to evaluate the benefits of Progestagen use. 158 incident cases were identified between 1985 and 1987 among women aged 40-64 years who were residents of King County, Washington. Detailed interviews were conducted and the responses were compared with those of 182 controls selected by random telephone digit dialling. The risk of endometrial cancer among women who had used unopposed oestrogen for more than 3 years was over five times that of women who had used no hormones (relative risk [RR] 5·7, 95% confidence interval [Cl] 2·5-12·8), whereas those who had also used a Progestagen for at least six months of that time had an RR of only 1·6 (95% Cl 0·6-3·9). The RR differed according to days per month that Progestagen was used: 2·4 (0·6-9·3) for Progestagen use of less than 10 days per month versus 1·1 (0·4-3·6) for use of 10 or more days per month. These results provide additional evidence that the use of Progestagen for 10 or more days per cycle can reduce the excess risk of endometrial cancer associated with long-term postmenopausal oestrogen use.