Ce-based metal-organic frameworks (MOFs) have recently gained scientific interest, since Ce is the most abundant rare-earth element in the Earth's crust and since their synthesis has some advantages, including first of all their redox activity, the high porosity of these crystalline materials, and Ce availability. In particular, Ce(iv)-based MOFs, such as Ce-UiO-66 and Ce-UiO-67, are synthesised under mild conditions. For most applications, the presence of functional groups in the frameworks is needed; in this context, linkers containing N-functionalities have been highlighted, as they allow for the incorporation of a large variety of metal cations.
View Article and Find Full Text PDFBackground: Striatal hyperdopaminergia is implicated in the pathoetiology of schizophrenia, but how this relates to dopaminergic midbrain activity is unclear. Neuromelanin (NM)-sensitive magnetic resonance imaging provides a marker of long-term dopamine function. We examined whether midbrain NM-sensitive magnetic resonance imaging contrast-to-noise ratio (NM-CNR) was higher in people with schizophrenia than in healthy control (HC) participants and whether this correlated with dopamine synthesis capacity.
View Article and Find Full Text PDFAt the energy-chemistry nexus, key molecules include carbon dioxide (CO), hydrogen (H), methane (CH), and ammonia (NH). The position of these four molecules and that of the more general family of synthetic macromolecular polymer blends (found in plastics) were cross-analyzed with the planetary boundary framework, and as part of five scientific policy roadmaps for the energy transition. According to the scenarios considered, the use of some of these molecular substances will be drastically modified in the coming years.
View Article and Find Full Text PDFMetal-organic frameworks (MOFs) featuring zirconium-based clusters are widely used for the development of functionalized materials due to their exceptional stability. In this study, we report the synthesis of a novel N,N,N-ligand compatible with a biphenyl dicarboxylic acid-based MOF. However, the resulting copper(I) complex exhibited unexpected coordination behaviour, lacking the intended trifold coordination motif.
View Article and Find Full Text PDFMale Sprague-Dawley rats received for 14 months 0, 15, 30 and 60 micrograms/ml of lead in drinking water. Both blood pressure and tissue lead were augmented with a dose-response effect, while cardiac inotropism was increased only in the rats treated with 60 ppm of lead. In the exposed animals, zinc and copper were unchanged in kidneys and testicles and augmented in the brain, while copper, but not zinc, was reduced in the heart.
View Article and Find Full Text PDFWeanling rats were fed a copper-deficient purified diet. The effects of varying the type of protein and supplements of copper and zinc on cardiovascular pathology and some biochemical parameters were investigated. It was found that cardiomyopathy developed in the copper-deficient groups.
View Article and Find Full Text PDFToxicol Appl Pharmacol
July 1983
In this study we verified the possibility that chronic exposure to inorganic mercury may induce hemodynamic changes in the rat by affecting some neurogenic and/or humoral mechanisms regulating cardiovascular function. For this reason, aortic blood pressure, maximum rate of rise of the left ventricular pressure, heart rate, and electrocardiogram were monitored under pentothal anesthesia in rats which received 50 micrograms/ml of mercury (as HgCL2) in drinking water for 320 days and in control rats. No pressor or electrocardiographic changes were found in mercury-treated animals, which showed increase of cardiac inotropism and decrease of the pressor and inotropic responses to bilateral carotid occlusion.
View Article and Find Full Text PDFChronic exposure of rats to cadmium (Cd) in drinking water induced elevated systolic and diastolic blood pressure. Heart rate, however, was lowered, suggesting that the hypertension in these rates may be due to an increase of the total peripheral resistance, possibly involving a central nervous system (CNS) component in Cd-induced hypertension. Urinary kallikrein activity was reduced in the exposed animals and may explain the previously reported antinatriuretic effect of Cd, since renal kallikrein is an enzyme responsible for the synthesis of kallidin, a potent vasodilator and natriuretic polypeptide.
View Article and Find Full Text PDFBull Environ Contam Toxicol
November 1979
A lead-intoxicated patient with extremely high blood lead levels and unexpectedly mild symptoms was studied prior to and following treatment with calcium disodium edetate (ethylenediaminetetraacetic acid) and then prior to and following oral administration of zinc sulfate. During chelation therapy, erythrocyte (delta)-aminolevulinic acid dehydratase (ALAD) activity decreased as blood lead levels fell. Urinary excretion of zinc increased and was more than 3.
View Article and Find Full Text PDFA patient who had hereditary tyrosinemia was observed during two illnesses to have characteristics of acute intermittent porphyria with associated hypertension. Metabolic studies revealed elevated levels of urinary aminolevulinic acid but normal levels of porphyrin metabolites associated with, and possibly explained by, decreased red blood cell activity of the zinc-dependent enzyme, aminolevulinic acid dehydratase. Zinc deficiency could not be directly associated with the diminished enzyme activity.
View Article and Find Full Text PDFJ Toxicol Environ Health
May 1976
This paper relates to the efficacy of a catalytic converter in reducing the levels of certain pollutants emitted from an automobile engine and to the reduction and/or elimination of gross biologic damages in animals exposed to emissions from an exhaust system containing such catalysts. Groups of rats were exposed to diluted emissions from an automobile engine with and without catalyst. Concomitantly, a comparative experiment was conducted by exposing a group of rats to carbon monoxide alone (575 mg/m3).
View Article and Find Full Text PDFJ Air Pollut Control Assoc
March 1976
Biochem Biophys Res Commun
July 1975