Bifunctional chelators have been successfully used to construct (64)Cu-labeled radiopharmaceuticals. Previously reported chelators with cross-bridged cyclam backbones have various essential features such as high stability of the copper(II) complex, high efficiency of radiolabeling at room temperature, and good biological inertness of the radiolabeled complex, along with rapid body clearance. Here, we report a new generation propylene-cross-bridged chelator with hybrid acetate/phosphonate pendant groups (PCB-TE1A1P) developed with the aim of combining these key properties in a single chelator. The PCB-TE1A1P was synthesized from cyclam with good overall yield. The Cu(II) complex of our chelator showed good robustness in kinetic stability evaluation experiments, such as acidic decomplexation and cyclic voltammetry studies. The Cu(II) complex of PCB-TE1A1P remained intact under highly acidic conditions (12 M HCl, 90 °C) for 8 d and showed quasi-reversible reduction/oxidation peaks at -0.77 V in electrochemical studies. PCB-TE1A1P was successfully radiolabeled with (64)Cu ions in an acetate buffer at 60 °C within 60 min. The electrophoresis study revealed that the (64)Cu-PCB-TE1A1P complex has net negative charge in aqueous solution. The biodistribution and in vivo stability study profiles of (64)Cu-PCB-TE1A1P indicated that the radioactive complex was stable under physiological conditions and cleared rapidly from the body. A whole body positron emission tomography (PET) imaging study further confirmed high in vivo stability and fast clearance of the complex in mouse models. In conclusion, PCB-TE1A1P has good potential as a bifunctional chelator for (64)Cu-based radiopharmaceuticals, especially those involving peptides.

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The rosuvastatin/ezetimibe (10/10 mg) FDC was bioequivalent to single agents concomitantly administered. A single dose of rosuvastatin/ezetimibe as the FDC or as single agents was well tolerated.
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Edited by Varda Rotter Keywords:Mitotic centromere-associated kinase (MCAK/Kif2C) Cellular senescence p53 Human primary cells a b s t r a c t Mitotic centromere-associated kinase (MCAK/Kif2C) plays a critical role in chromosome movement and segregation with ATP-dependent microtubule depolymerase activity. However, its role in cellular senescence remains unclear. MCAK/Kif2C expression decreased in human primary cells under replicative and premature senescence. MCAK/Kif2C down-regulation in young cells induced premature senescence. MCAK/Kif2C overexpression in old cells partially reversed cell senescence. Senescence phenotypes by MCAK/Kif2C knockdown were observed in p16-knockdown cells, but not in p53-knockdown cells. These results suggest that MCAK/Kif2C plays an important role in the regulation of cellular senescence through a p53-dependent pathway and might contribute to tissue/organism aging and protection of cellular transformation.

Osteoporosis is a common skeletal disorder, often leading to fragility fracture. Combination therapy with raloxifene, a selective estrogen receptor modulator,and cholecalciferol (vitamin D 3 ) has been proposed to improve the overall efficacy and increase compliance of raloxifene therapy for postmenopausal osteoporosis. To our knowledge, there has been no report of any study on the pharmacokinetic interaction between raloxifene and cholecalciferol. This study aimed to evaluate the possible pharmacokinetic interactions between raloxifene and cholecalciferol in healthy adult male Korean volunteers. Twenty subjects completed this open-label, randomized, single-dose, 3-period, 6-sequence, crossover phase 1 study with a 14-day washout period. Serial blood samples were collected from 20 hours before dosing to 96 hours after dosing. The plasma concentrations of raloxifene and cholecalciferol were determined using a validated method for high-performance liquid chromatography with tandem mass spectrometry. The geometric mean ratios (90%CIs) for area under the plasma concentration-time curve from time 0 to the last quantifiable time point and maximum plasma concentration of raloxifene with or without cholecalciferol were 1.02 (0.87-1.20) and 0.87 (0.70-1.08), respectively. For baseline-corrected cholecalciferol, geometric mean ratios (90%CIs) of area under the plasma concentration-time curve from time 0 to the last quantifiable time point and maximum plasma concentration with or without raloxifene were 1.01 (0.93-1.09) and 0.99 (0.92-1.06),respectively.Concurrent treatment with raloxifene and cholecalciferol was generally well tolerated. These results suggest that raloxifene and cholecalciferol have no clinically relevant pharmacokinetic drug-drug interactions when administered concurrently. All treatments were well tolerated, with no serious adverse events.