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Anticancer activity of Pd complexes 1-5 with bidentate N-heteroaromatic hydrazone ligands was investigated on human acute monocytic leukemia (THP-1; cells in a suspension) and human mammary adenocarcinoma (MCF-7; two-dimensional layer and three-dimensional spheroid tumor model) cell lines. For the Pd(II) complexes with condensation products of ethyl hydrazainoacetate and quinoline-8-carboxaldehyde (complex 1) and 2-formylpyridine (complex 3), for which apoptosis was determined as a mechanism of anticancer activity, further investigation revealed that they arrest the cell cycle in G0/G1 phase, induce generation of reactive oxygen species and inhibit Topoisomerase I in vitro. In silico studies corroborate experimental findings that these complexes show topoisomerase inhibition activity in the micromolar range and indicate binding to a DNA's minor groove as another potential target. Based on the results obtained by circular dichroism and fluorescence spectroscopy measurements, the most active complexes are suitable to be delivered to a blood stream via human serum albumin., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objectives: Acute kidney injury (AKI) is defined as a decrease in glomerular filtration rate with an increase in serum creatinine (sCr). Perinatal asphyxia (PNA) may be etiological factor for AKI with oxidative stress also implicated. Paraoxonase 1 (PON1) activity has been reported to be decreased in renal disease. The aim of our study was to evaluate paraoxonase 1 (PON1) activity and oxidative stress during the first hours and first days of life and to determine if these parameters could discriminate neonates having AKI from those who do not., Methods: Serum samples at different time points after birth were obtained from 64 preterm newborns with PNA (45 defined as having AKI, 19 as non-AKI). Clinical markers, sCr, total oxidant status (TOS), total antioxidant status (TAS) and PON1 activity were measured., Results: The AKI group had more newborns with hypoxic ischemic encephalopathy, significantly higher serum creatinine (sCr) at 3 and 7d, total antioxidant status (TAS) at 7d; decreased PON1 at 4h, 6h and 7d than the non-AKI group. Within the AKI group, significant positive correlations were found between PON1 activity at 2h and TAS at 2h, PON1 activity at 4h and base deficit (BD); whereas negative correlations between PON1 activity at 2h and ΔsCr (at 24h and at 3d), PON1 activity at 7d and ΔsCr (at 24h and 3d). Oxidative stress status parameters indicated excellent discriminative potential at 4h, 6h and 7d., Conclusions: AKI neonates were characterised by a marked decrease in PON1 activity. PON1 activity may be an important factor for discrimination of newborns having AKI from those that do not., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous design of smart HA micro- and nano-structures with advanced therapeutic potentials., (Copyright © 2016 Elsevier B.V. All rights reserved.)

3H-medroxyprogesterone acetate (MPA) was synthesized by selective catalytic tritiation of the delta1-olefinic bond of 6alpha-methyl-17alpha-hydroxy-pregna-1,4-diene-3,20-dione acetate. The metabolic clearance rate of MPA (MCRMPA) was determined in 9 female Rhesus monkeys by the single injection technique. The blood MCRMPA was 201 +/- 19 L/day (42.2 +/- 4.0 L/day/kg) which was approximately the same as that reported for progesterone clearance in the monkey. We conclude that a greater biological activity of MPA compared to progesterone cannot be related to its prolonged retention in the blood. Although both MPA and amino-glutethimide alter the rate of steroid metabolism in some species, neither of these agents influences the metabolic clearance rate of 3H-MPA in the monkey.

[3H]6alpha-methylprogesterone (6MP) was synthesized by selective catalytic tritiation of the delta1-olefinic bond of 6alpha-methylpregna-1,4-diene-3,20-dione. The metabolic clearance rate of 6MP (MCR6MP) was determined in 6 women by the single injection technique. The plasma MCR6MP was 4047 +/- 298 L/day (59 +/- 15 L/day/kg) which was higher than the MCR of progesterone and medroxyprogesterone acetate (6alpha-methyl-17alpha-hydroxy-pregna-4-ene-3,20-dione acetate). The high clearance was not due to binding or metabolism of 6MP by red cells. Although 6MP was bound to CBG with a lower affinity than progesterone, this could not entirely explain the high MCR6MP. When considered with the reports of progesterone and medroxyprogesterone acetate clearance, the present studies suggest that the 6alpha-substitution of progesterone leads to an increased rate of steroid metabolism in women.