Lipo-prostaglandin E1 improves renal hypoxia evaluated by BOLD-MRI in patients with diabetic kidney disease
CLINICAL IMAGING
Authors: Li, Zhi-Cheng; Cai, Yu-Zhe; Tang, Zhi-Gang; Zuo, Pan-Li; Liu, Rong-Bo; Liu, Fang
Abstract
Objective: To evaluate the effect of lipo-PGE1 on renal hypoxia in patients with DKD by BOLD-MRI. Materials and methods: All patients were divided into DKD group and CKD-without-diabetes group. All patients received intravenous 10 mu g lipo-PGE1 once daily for 14 days. BOLD-MRI was performed before and after lipo-PGE1 administration to acquire renal CR2* and MR2* values. Results: Renal MR2* value in DKD group after lipo-PGE1 treatment were significantly decreased compared with the baseline. However, no significant differences in MR2* values were found in the CKD-without-diabetes group. Conclusions: Lipo-PGE1 was shown to improve kidney medullary oxygenation in patients with DKD.
Redox control on chromium isotope behaviour in silicate melts in contact with magnesiochromite
GEOCHIMICA ET COSMOCHIMICA ACTA
Authors: Bonnand, P.; Bruand, E.; Matzen, A. K.; Jerram, M.; Schiavi, F.; Wood, B. J.; Boyet, M.; Halliday, A. N.
Abstract
Transition metal isotopes are particularly useful for understanding the conditions under which magmatic processes occur. Moreover, those with more than one oxidation state (e.g. Cr2+, Cr3+ and Cr6+) may also provide powerful constraints on the evolution of the redox state of the mantle over time. By investigating the Cr isotopic compositions in both magnesiochromite and silicate melts during experiments performed at 1300 degrees C and under controlled redox conditions (-12 < log/O-2 < -4), this study presents the first experimental petro-isotopic investigation of Cr isotope fractionation and reveals clear systematics between Cr concentration, isotopic compositions and fO(2). Two series of experiments were performed to study (a) the dissolution of a natural magnesiochromite into Cr-free silicate melts (series A) and (ii) the crystallisation of magnesiochromite from Cr-doped silicate melts (series B). In agreement with previous studies, the Cr solubility in the silicate melts at equilibrium with magnesiochromite is strongly controlled by oxygen fugacity. Melts produced at low fO(2) are enriched in Cr compared to more oxidised melts. In series A experiments, the Cr isotopic composition of silicate melts are lighter than the initial chromite starting material. The experiments, performed at -12 < logfO(2) < -6, reveal that Cr isotopic compositions of the silicate melts are correlated with fO(2). This demonstrates that, as for the Cr solubility, Cr isotopes are sensitive to fO(2) and could be used to track changes in redox conditions in high-temperature processes. Furthermore, the Cr isotopic compositions of silicate melts that are reacted under more oxidising conditions (log/O-2 > -6) are much lighter than those of melts equilibrated with magnesiochromite at lower oxygen fugacity. The observed variations can be explained by changes in bonding environment for Cr under oxidised conditions in the silicate melts and/or in the magnesiochromite grains. Similarly, the second set of experiments designed to study fractional crystallisation (series B) suggest that Cr isotope fractionation is larger under oxidising conditions. (C) 2020 Elsevier Ltd. All rights reserved.