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Pamiparib (BGB-290) is an orally bioavailable, small molecule inhibitor of poly (ADP-ribose) polymerase 1 (PARP1) and PARP2. A reversed-phase LC with tandem mass spectrometry method was developed and fully validated for determining total and unbound pamiparib concentrations in human plasma and brain tumor tissue. Plasma and tissue homogenate samples were prepared by methanol protein precipitation. Pamiparib and the internal standard [(13)C(2),(15)N(2)]pamiparib were separated on a Waters BEH C(18) (50 × 2.1 mm, 1.7 μm) column, with a gradient elution consisting of mobile phases A (0.1% formic acid in water) and B (0.1% formic acid in acetonitrile) at a flow rate of 0.25 mL/min. The analytes were monitored with multiple reaction monitoring mode under positive electrospray ionization. The method was fully validated for specificity, linearity, accuracy and precision, matrix effect and recovery, and short- and long-term stability. The lower limit of quantitation was 0.5 nM of pamiparib in plasma or tissue homogenate. The calibration curve was linear over the pamiparib concentration range of 0.5–1000 nM in plasma. The intra- and inter-day precision and accuracy were within the generally accepted criteria for bioanalytical method. Pamiparib was stable in plasma at −80°C for at least 6 months. The method was successfully applied to assess the plasma and tumor pharmacokinetics of total and unbound pamiparib in patients with glioma.

Suicide is commonly found in patients with major depressive disorder (MDD), while the associations among depressive symptoms and their relationships with suicidal risk remain unclear. This study identified the symptoms associated with suicidal risk and the most central symptoms in the MDD networks based on both self-reported and clinical-interview scales. A total of 446 outpatients with MDD were recruited. The Mini International Neuropsychiatric Interview (MINI) was used to assess the suicidal risk. The 13-item Beck Depression Inventory (BDI-13) and 17-item Hamilton Depression Rating Scale (HAMD-17) were used to measure the depressive symptoms. Network analysis was used to estimate the network models. Ten symptoms in the BDI-13 network were related to suicidal risk, among which sadness had the strongest association. Among the six symptoms in the HAMD-17 network that were associated with suicidal risk, guilty feeling was the strongest. Sense of failure was the most central symptom in the BDI-13 network, while depressed mood had the highest centrality in the HAMD-17 network. The depressive symptoms related to suicide risk and the clinical features of MDD showed different characteristics based on different assessment types. Combining self-reported and clinician-rated assessments in future studies and clinical practice might lead to some new findings.

The knowledge of transporter protein expression and function at the human blood-brain barrier (BBB) is critical to prediction of drug BBB penetration and design of strategies for improving drug brain/brain tumor delivery. This study determined absolute transporter protein abundances in isolated microvessels of human normal brain (N=30), glioblastoma (N=47), rat (N=10) and This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi:10.1002/CPT.1710 mouse brain (N=10), and cell membranes of MDCKII cell lines, using targeted proteomics. In glioblastoma microvessels, ABCB1, ABCG2, MCT1, GLUT1, Na/K ATPase, and Claudin-5 protein levels were significantly reduced, while LAT1 was increased and GLU1 remained the same, as compared to human normal brain microvessels. ABCC4, OATP1A2, OATP2B1, and OAT3 were undetectable in microvessels of both human brain and glioblastoma. Species difference in BBB transporter abundances was noted. Cellular permeability experiments and modeling simulations suggested that not a single apical uptake transporter, but a vectorial transport system consisting of an apical uptake transporter and basolateral efflux mechanism was required for efficient delivery of poor transmembrane permeability drugs from the blood to brain.