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Hiroyuki Daida - One of the best experts on this subject based on the ideXlab platform.
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Probucol therapy improves long term 10 year survival after complete revascularization a propensity analysis
Atherosclerosis, 2012Co-Authors: Takatoshi Kasai, Katsumi Miyauchi, Naozumi Kubota, Kan Kajimoto, Atsushi Amano, Hiroyuki DaidaAbstract:Abstract Objective Probucol has anti-atherosclerotic properties and has been shown to reduce post-angioplasty coronary restenosis. However, the effect of Probucol therapy on long-term (>10 years) outcome following coronary revascularization is less well established. Accordingly, we sought to determine if Probucol therapy at the time of complete coronary revascularization reduces mortality in patients with coronary artery disease (CAD). Methods We collected data from 1694 consecutive patients who underwent complete revascularization (PCI and/or bypass surgery). Mortality data were compared between patients administered Probucol and those not administered Probucol at the time of revascularization. A propensity score (PS) was calculated to evaluate the effects of variables related to decisions regarding Probucol administration. The association of Probucol use and mortality was assessed using 3 Cox regression models, namely, conventional adjustment, covariate adjustment using PS, and matching patients in the Probucol and no-Probucol groups using PS. Results In the pre-match patients, 231 patients were administered Probucol (13.6%). During follow-up [10.2 (SD, 3.2) years], 352 patients died (including 113 patients who died of cardiac-related issues). Probucol use was associated with significant decrease in all-cause death (hazard ratio [HR], 0.65; P = 0.036 [conventional adjustment model] and HR, 0.57; P = 0.008 [PS adjusted model]). In post-match patients ( N = 450, 225 matched pair), the risk of all-cause mortality was significantly lower in the Probucol group than in the no-Probucol group (HR, 0.45; P = 0.002). Conclusion In CAD patients who had undergone complete revascularization, Probucol therapy was associated with a significantly reduced risk of all-cause mortality.
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Effect of Probucol on repeat revascularization rate after percutaneous transluminal coronary angioplasty (from the Probucol Angioplasty Restenosis Trial [PART]).
The American journal of cardiology, 2000Co-Authors: Hiroyuki Daida, Hisashi Yokoi, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Yasuro Nakata, Yasunori Kutsumi, Shinichiro Nishiyama, Shigeru Oshima, Sugao IshiwataAbstract:To address the issue of whether Probucol reduces clinical events after percutaneous transluminal coronary angioplasty (PTCA), we surveyed clinical status at 1 year after PTCA of 101 patients who had entered the Probucol Restenosis Angioplasty Trial. Repeat angioplasty at index lesions were required in 5 patients in the Probucol group and in 12 in the control group, suggesting that Probucol administered beginning 4 weeks before PTCA reduces repeat revascularization rates for 1 year.
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effectiveness of an antioxidant in preventing restenosis after percutaneous transluminal coronary angioplasty the Probucol angioplasty restenosis trial
Journal of the American College of Cardiology, 1997Co-Authors: Hisashi Yokoi, Hiroyuki Daida, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Hitoshi Tomihara, Yasuro Nakata, Yasunori Kutsumi, Shigeru Ohshima, Shinichiro NishiyamaAbstract:Abstract Objectives. The Probucol Angioplasty Restenosis Trial was a prospective, randomized, controlled study that investigated the effectiveness of Probucol therapy in reducing the rate of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Background. Antioxidants have an inhibitory effect on smooth muscle cell growth in experiments in vitro and in vivo, which suggests a possible pharmacologic effect on restenosis after PTCA. Methods. One hundred one patients were randomly assigned to receive 1,000 mg/day of Probucol or control (no lipid-lowering) therapy 4 weeks before PTCA. After 4 weeks of premedication, both groups underwent PTCA. Probucol was continued until follow-up angiography 24 weeks after PTCA. Angiographic results were analyzed at a core laboratory by quantitative coronary angiography. Results. Dilation was successful in 46 of 50 patients in the Probucol group and 45 of 51 in the control group. At follow-up angiography 24 weeks after angioplasty, angiographic restenosis occurred in 9 (23%) of 40 patients in the Probucol group and 22 (58%) of 38 in the control group (p = 0.001). Minimal lumen diameter was 1.49 ± 0.75 mm (mean ± SD) in the Probucol group and 1.13 ± 0.65 mm in the control group (p = 0.02). Percent diameter stenosis at follow-up angiography in the Probucol group was significantly lower than that in the control group (43.9% vs. 56.4%, p = 0.009). The late loss was 0.37 ± 0.69 mm in the Probucol group and 0.60 ± 0.62 mm in the control group (p = 0.13). The loss/gain ratio was 0.32 ± 0.74 in the Probucol group and 0.56 ± 0.81 in the control group (p = 0.059). Net gain was greater in the Probucol group than in the control group (0.77 ± 0.70 vs. 0.48 ± 0.59 mm, p = 0.053). Conclusions. Probucol administered beginning 4 weeks before PTCA appears to reduce restenosis rates.
Keiji Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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nanoparticle formation from Probucol pvp sodium alkyl sulfate co ground mixture
International Journal of Pharmaceutics, 2009Co-Authors: Chalermphon Wanawongthai, Adchara Pongpeerapat, Kenjirou Higashi, Yuichi Tozuka, Kunikazu Moribe, Keiji YamamotoAbstract:Abstract Nanoparticles of a poorly water-soluble drug, Probucol, have been obtained by co-grinding with PVP and SDS. The purpose of this study was to investigate the effect of the alkyl chain length of sodium alkyl sulfates (C n S, n = 6, 8, 12, 16 and 18) on Probucol nanoparticle formation. From the results of particle size determination and quantitative measurement of nanoparticle fraction of Probucol by HPLC, it was found that the alkyl chain length of the sodium alkyl sulfate affected the Probucol nanoparticle formation. The efficiency, based on the quantitative determination of nanoparticles, was in the order: C18S > C16S > C12S > C8S > C6S. Probucol nanoparticles of less than 800 nm were effectively produced (more than 95%) with the increase of the amount of surfactants. 13 C solid-state NMR of co-ground mixtures showed a new peak originating from the Probucol interaction with PVP together with the existence of Probucol crystal peaks. Excess amounts of surfactants were expected to play an important role for stabilizing the Probucol nanoparticles in the suspension via the electrostatic repulsive effect.
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Nanoparticle formation from Probucol/PVP/sodium alkyl sulfate co-ground mixture.
International journal of pharmaceutics, 2009Co-Authors: Chalermphon Wanawongthai, Adchara Pongpeerapat, Kenjirou Higashi, Yuichi Tozuka, Kunikazu Moribe, Keiji YamamotoAbstract:Abstract Nanoparticles of a poorly water-soluble drug, Probucol, have been obtained by co-grinding with PVP and SDS. The purpose of this study was to investigate the effect of the alkyl chain length of sodium alkyl sulfates (C n S, n = 6, 8, 12, 16 and 18) on Probucol nanoparticle formation. From the results of particle size determination and quantitative measurement of nanoparticle fraction of Probucol by HPLC, it was found that the alkyl chain length of the sodium alkyl sulfate affected the Probucol nanoparticle formation. The efficiency, based on the quantitative determination of nanoparticles, was in the order: C18S > C16S > C12S > C8S > C6S. Probucol nanoparticles of less than 800 nm were effectively produced (more than 95%) with the increase of the amount of surfactants. 13 C solid-state NMR of co-ground mixtures showed a new peak originating from the Probucol interaction with PVP together with the existence of Probucol crystal peaks. Excess amounts of surfactants were expected to play an important role for stabilizing the Probucol nanoparticles in the suspension via the electrostatic repulsive effect.
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In vivo assessment of oral administration of Probucol nanoparticles in rats.
Biological & pharmaceutical bulletin, 2008Co-Authors: Jyutaro Shudo, Chalermphon Wanawongthai, Adchara Pongpeerapat, Kunikazu Moribe, Keiji YamamotoAbstract:Pharmacokinetic profiles of Probucol were evaluated after oral administration of the various nanosuspensions in rats. Probucol nanoparticles were prepared by co-grinding with various molecular weights of polyvinylpyrrolidone (PVP K12, PVP K17 and PVP K30) and sodium dodecyl sulfate (SDS). The average particle sizes of Probucol after dispersing the ternary ground mixtures (GMs), Probucol/PVP K12/SDS, Probucol/PVP K17/SDS and Probucol/PVP K30/SDS into water were 28, 75 and 89 nm respectively. The ternary GM suspensions with PVP K17/SDS and PVP K30/SDS were stable at 25 °C. However the particle size of Probucol from the ternary GM with PVP K12/SDS gradually increased. Pharmacokinetic profiles of Probucol indicated that variation in particle surface condition covered with PVP and SDS in addition to the particle size affected the improvement of in vivo absorption of Probucol. The ternary GM with PVP K12/SDS exhibited a superior improvement of Probucol absorption compared to the GMs with PVP K17/SDS and PVP K30/SDS. The binary GM with PVP or SDS and physical mixtures with PVP and/or SDS did not show significant differences in the area under the plasma concentration–time curve compared to the unprocessed Probucol. In conclusion, preparation of Probucol nanoparticles by co-grinding with PVP K12 and SDS could be a promising method for bioavailability enhancement.
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Molecular Interaction among Probucol/PVP/SDS Multicomponent System Investigated by Solid-State NMR
Pharmaceutical Research, 2006Co-Authors: Adchara Pongpeerapat, Kenjirou Higashi, Yuichi Tozuka, Kunikazu Moribe, Keiji YamamotoAbstract:Purpose Effects of polyvinylpyrrolidone (PVP) molecular weight on the solid-state intermolecular interactions among Probucol/PVP/sodium dodecyl sulfate (SDS) ternary ground mixtures (GM) and the formation of nanoparticles were investigated by solid-state NMR spectroscopy. Materials and Methods Ternary GMs of Probucol were prepared with PVP (K12, K17, K30 or K90) and SDS at a weight ratio of 1:3:1 and were ground for 15, 30 and 60 min. Solid-state interactions were evaluated using powder X-ray diffraction (PXRD) and solid-state cross polarization/magic angle spinning (CP/MAS) ^13C NMR spectroscopy. A high resolution scanning electron microscopy (SEM) was employed to observe nanoparticles of Probucol in the GM. Results The solid-state ^13C CP/MAS NMR results indicate that the low molecular weight PVP interacts with Probucol and SDS more strongly than the high molecular weight PVP in the ternary GM. This finding was consistent with the result that smaller drug nanoparticles were obtained using low molecular weight of PVP. SEM images of Probucol/PVP K12/SDS confirmed the presence of nanoparticles (15–25 nm) in the GM. Conclusions Grinding-induced solid-state interactions among drug, PVP and SDS could be detected using solid state ^13C NMR. The interactions in both Probucol-PVP and PVP-SDS should occur simultaneously to generate nanometer-sized particles of Probucol.
Shinichiro Nishiyama - One of the best experts on this subject based on the ideXlab platform.
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Effect of Probucol on repeat revascularization rate after percutaneous transluminal coronary angioplasty (from the Probucol Angioplasty Restenosis Trial [PART]).
The American journal of cardiology, 2000Co-Authors: Hiroyuki Daida, Hisashi Yokoi, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Yasuro Nakata, Yasunori Kutsumi, Shinichiro Nishiyama, Shigeru Oshima, Sugao IshiwataAbstract:To address the issue of whether Probucol reduces clinical events after percutaneous transluminal coronary angioplasty (PTCA), we surveyed clinical status at 1 year after PTCA of 101 patients who had entered the Probucol Restenosis Angioplasty Trial. Repeat angioplasty at index lesions were required in 5 patients in the Probucol group and in 12 in the control group, suggesting that Probucol administered beginning 4 weeks before PTCA reduces repeat revascularization rates for 1 year.
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effectiveness of an antioxidant in preventing restenosis after percutaneous transluminal coronary angioplasty the Probucol angioplasty restenosis trial
Journal of the American College of Cardiology, 1997Co-Authors: Hisashi Yokoi, Hiroyuki Daida, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Hitoshi Tomihara, Yasuro Nakata, Yasunori Kutsumi, Shigeru Ohshima, Shinichiro NishiyamaAbstract:Abstract Objectives. The Probucol Angioplasty Restenosis Trial was a prospective, randomized, controlled study that investigated the effectiveness of Probucol therapy in reducing the rate of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Background. Antioxidants have an inhibitory effect on smooth muscle cell growth in experiments in vitro and in vivo, which suggests a possible pharmacologic effect on restenosis after PTCA. Methods. One hundred one patients were randomly assigned to receive 1,000 mg/day of Probucol or control (no lipid-lowering) therapy 4 weeks before PTCA. After 4 weeks of premedication, both groups underwent PTCA. Probucol was continued until follow-up angiography 24 weeks after PTCA. Angiographic results were analyzed at a core laboratory by quantitative coronary angiography. Results. Dilation was successful in 46 of 50 patients in the Probucol group and 45 of 51 in the control group. At follow-up angiography 24 weeks after angioplasty, angiographic restenosis occurred in 9 (23%) of 40 patients in the Probucol group and 22 (58%) of 38 in the control group (p = 0.001). Minimal lumen diameter was 1.49 ± 0.75 mm (mean ± SD) in the Probucol group and 1.13 ± 0.65 mm in the control group (p = 0.02). Percent diameter stenosis at follow-up angiography in the Probucol group was significantly lower than that in the control group (43.9% vs. 56.4%, p = 0.009). The late loss was 0.37 ± 0.69 mm in the Probucol group and 0.60 ± 0.62 mm in the control group (p = 0.13). The loss/gain ratio was 0.32 ± 0.74 in the Probucol group and 0.56 ± 0.81 in the control group (p = 0.059). Net gain was greater in the Probucol group than in the control group (0.77 ± 0.70 vs. 0.48 ± 0.59 mm, p = 0.053). Conclusions. Probucol administered beginning 4 weeks before PTCA appears to reduce restenosis rates.
Hisashi Yokoi - One of the best experts on this subject based on the ideXlab platform.
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Effect of Probucol on repeat revascularization rate after percutaneous transluminal coronary angioplasty (from the Probucol Angioplasty Restenosis Trial [PART]).
The American journal of cardiology, 2000Co-Authors: Hiroyuki Daida, Hisashi Yokoi, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Yasuro Nakata, Yasunori Kutsumi, Shinichiro Nishiyama, Shigeru Oshima, Sugao IshiwataAbstract:To address the issue of whether Probucol reduces clinical events after percutaneous transluminal coronary angioplasty (PTCA), we surveyed clinical status at 1 year after PTCA of 101 patients who had entered the Probucol Restenosis Angioplasty Trial. Repeat angioplasty at index lesions were required in 5 patients in the Probucol group and in 12 in the control group, suggesting that Probucol administered beginning 4 weeks before PTCA reduces repeat revascularization rates for 1 year.
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effectiveness of an antioxidant in preventing restenosis after percutaneous transluminal coronary angioplasty the Probucol angioplasty restenosis trial
Journal of the American College of Cardiology, 1997Co-Authors: Hisashi Yokoi, Hiroyuki Daida, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Hitoshi Tomihara, Yasuro Nakata, Yasunori Kutsumi, Shigeru Ohshima, Shinichiro NishiyamaAbstract:Abstract Objectives. The Probucol Angioplasty Restenosis Trial was a prospective, randomized, controlled study that investigated the effectiveness of Probucol therapy in reducing the rate of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Background. Antioxidants have an inhibitory effect on smooth muscle cell growth in experiments in vitro and in vivo, which suggests a possible pharmacologic effect on restenosis after PTCA. Methods. One hundred one patients were randomly assigned to receive 1,000 mg/day of Probucol or control (no lipid-lowering) therapy 4 weeks before PTCA. After 4 weeks of premedication, both groups underwent PTCA. Probucol was continued until follow-up angiography 24 weeks after PTCA. Angiographic results were analyzed at a core laboratory by quantitative coronary angiography. Results. Dilation was successful in 46 of 50 patients in the Probucol group and 45 of 51 in the control group. At follow-up angiography 24 weeks after angioplasty, angiographic restenosis occurred in 9 (23%) of 40 patients in the Probucol group and 22 (58%) of 38 in the control group (p = 0.001). Minimal lumen diameter was 1.49 ± 0.75 mm (mean ± SD) in the Probucol group and 1.13 ± 0.65 mm in the control group (p = 0.02). Percent diameter stenosis at follow-up angiography in the Probucol group was significantly lower than that in the control group (43.9% vs. 56.4%, p = 0.009). The late loss was 0.37 ± 0.69 mm in the Probucol group and 0.60 ± 0.62 mm in the control group (p = 0.13). The loss/gain ratio was 0.32 ± 0.74 in the Probucol group and 0.56 ± 0.81 in the control group (p = 0.059). Net gain was greater in the Probucol group than in the control group (0.77 ± 0.70 vs. 0.48 ± 0.59 mm, p = 0.053). Conclusions. Probucol administered beginning 4 weeks before PTCA appears to reduce restenosis rates.
Sugao Ishiwata - One of the best experts on this subject based on the ideXlab platform.
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Effect of Probucol on repeat revascularization rate after percutaneous transluminal coronary angioplasty (from the Probucol Angioplasty Restenosis Trial [PART]).
The American journal of cardiology, 2000Co-Authors: Hiroyuki Daida, Hisashi Yokoi, Yoichi Kuwabara, Hideo Nishikawa, Fumimaro Takatsu, Yasuro Nakata, Yasunori Kutsumi, Shinichiro Nishiyama, Shigeru Oshima, Sugao IshiwataAbstract:To address the issue of whether Probucol reduces clinical events after percutaneous transluminal coronary angioplasty (PTCA), we surveyed clinical status at 1 year after PTCA of 101 patients who had entered the Probucol Restenosis Angioplasty Trial. Repeat angioplasty at index lesions were required in 5 patients in the Probucol group and in 12 in the control group, suggesting that Probucol administered beginning 4 weeks before PTCA reduces repeat revascularization rates for 1 year.