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Altered pharmacokinetics (PK) in subjects with chronic kidney disease (CKD) may lead to dosing adjustment of certain drugs in subjects with CKD. It can be valuable to quantitatively predict PK in CKD for the management of drug dosing in these subjects. We developed physiologically based pharmacokinetic (PBPK) models of seven renally eliminated drugs: adefovir, avibactam, entecavir, famotidine, ganciclovir, oseltamivir carboxylate, and sitagliptin. These drugs are all substrates of renal organic anion transporters (OATs). Drug models verified using PK data from healthy subjects (HS) were coupled with physiological models representing CKD that incorporated prior knowledge of effects of CKD on hepatic and renal elimination. The models reasonably described clinically observed PK changes in subjects with CKD (compared to subjects with normal renal function), with predicted AUC changes within 50% of the observed changes. PBPK models can be used to prospectively predict PK of renally eliminated OAT substrates in subjects with CKD.

Drug transporters play a key role in the absorption, distribution, and elimination of many drugs, and they appear to be important determinants of therapeutic and adverse drug activities. Although a large body of data pertaining to drug transporters is available, there are few databases that inform drug developers, regulatory agencies, and academic scientists about transporters that are important in drug action and disposition. In this article, we inform the scientific community about the UCSF-FDA TransPortal, a new and valuable online resource for research and drug development.

In this work, homogeneous surface oxidation of hafnium disulfide (HfS2) is achieved by an extremely simple thermal treatment, i.e., mild oxidization in air. Due to the high thermal stability of hafnium dioxide (HfO2), atomically flat HfO2 is formed on top of unoxidized HfS2 and unlimited layer-by-layer oxidation is observed. The thickness of HfO2 can be controlled by oxidation temperature and time. The HfO2 layer fabricated by the oxidation of HfS2 is smooth and atomically flat with roughness comparable to that of pristine HfS2. Growth of a high-quality, uniform, atomically flat oxide film on top of semiconductor is the first step for the fabrication of field effect transistors and metal-insulator-semiconductor devices. Thus, our results will facilitate the future fabrication of HfO2 films with atomic-scale thickness. [ABSTRACT FROM AUTHOR]

Magnetic exchange interactions in Mn3O4 spinel systems are complicated due to the presence of magnetic frustration between one tetrahedral and two octahedral sites, and the strongly correlated Jahn–Teller crystal distortion due to the singly occupied eg band of Mn3+ cations at the octahedral site. In general, the tetrahedral–octahedral exchange interaction is the most dominant interaction among the other two interactions which enforces the octahedral and tetrahedral spins to align parallel to themselves. Doping of Cr3+ ions (with the empty eg band) at the octahedral sites of Mn3O4 reduces the Jahn–Teller distortion and the magnetic moment in the system and hence it affects the magnetic anisotropy, magnetic exchange interaction, and magnetic frustration. In this manuscript, we have investigated the variations in these properties of the Mn2.7Cr0.3O4 and Mn1.5Cr1.5O4 systems and compared them to those of the documented parent Mn3O4 to unveil the evolution of these cross interactions. The neutron diffraction results disclose the noncollinear magnetic structure of Mn2.7Cr0.3O4, while Mn1.5Cr1.5O4 shows a collinear magnetic structure [G. D. Dwivedi, C. W. Wang, S. M. Kumawat and H. Chou, Appl. Phys. Lett., 2020, 116, 182406]. A comparative study of the magnetic structure and exchange interactions (calculated using the TB2J method) of the low doping Mn2.7Cr0.3O4 reveals that the exchange interaction between the nearest octahedral–octahedral cations is the most prominent due to the ionic size effect, which is contrary to the general understanding of spinel systems. However, the exchange interactions in the high doping cubic Mn1.5Cr1.5O4 switched back to the dominant AFM interaction between tetrahedral–octahedral ions due to the smaller moment of Cr ions. [ABSTRACT FROM AUTHOR]