North Atlantic Heat Transport Convergence Derived from a Regional Energy Budget Using Different Ocean Heat Content Estimates.

This study uses an oceanic energy budget to estimate the ocean heat transport convergence in the North Atlantic during 2005-2018. The horizontal convergence of the ocean heat transport is estimated using ocean heat content tendency primarily derived from satellite altimetry combined with space gravimetry. The net surface energy fluxes are inferred from mass-corrected divergence of atmospheric energy transport and tendency of the ECMWF ERA5 reanalysis combined with top-of-the-atmosphere radiative fluxes from the clouds and the Earth's radiant energy system project.

Enhancing the Uptake of Earth Observation Products and Services in Africa Through a Multi-level Transdisciplinary Approach.

Unlabelled: Africa stands to gain from Earth Observation (EO) science, products and applications. However, its use and application remain below potential on the continent. This article examines how EO can better serve the needs of African users.

Local sea level trends, accelerations and uncertainties over 1993-2019.

Satellite altimetry missions provide a quasi-global synoptic view of sea level variations over more than 25 years and provide regional sea level (SL) indicators such as trends and accelerations. Estimating realistic uncertainties on these quantities is crucial to address current climate science questions. While uncertainty estimates are available for the global mean sea level (GMSL), information is not available at local scales so far.

Activation of human neutrophils by electronically transmitted phorbol-myristate acetate.

We report the transfer of the activity of 4-phorbol-12-beta-myristate-13-acetate (PMA) by electronic means. Neutrophils were placed at 37 degrees C on one coil attached to an oscillator, while PMA was placed on another coil at room temperature. The oscillator was then turned on for 15 min, after which cells were usually further incubated for up to 45 min at 37 degrees C before measurement of reactive oxygen metabolites (ROMs) production.

Lay theories of anorexia nervosa: a discourse analytic study.

Previous studies on lay theories of anorexia nervosa have examined the 'accuracy' of lay knowledge, and the identification of factors by family and friends that would encourage early interventions (Huon, Brown, & Morris, 1988, 7, 239-252; Murray, Touyz, & Beumont, 1990, 9, 87-93). In contrast to these approaches, we examine lay theories of anorexia nervosa using a critical psychology perspective. We argue that the use of a discourse analysis methodology enables the examination of the construction of lay theories through dominant concepts and ideas.

Presence of paf-acether in human blood after thin-layer chromatography, but not after high-performance liquid chromatography purification.

After HPLC purification of human blood extracts, paf-acether (paf) was found exclusively as a lipoprotein-bound compound (lipopaf), whereas free-paf was absent. When the same samples (or lipopaf recovered from HPLC) were purified by TLC, both free-paf and lipopaf were detected. The free-paf detected in blood samples could thus result from lipopaf dissociation during TLC purification.

Tissue levels of histamine, PAF-acether and lysopaf-acether in carrageenan-induced granuloma in rats.

The tissue concentrations of several inflammatory mediators were determined from day 0 to day 60 in granuloma induced in rats (n = 105) by injection of carrageenan in the fascia of the latissimus dorsi muscle. Noncollagen proteins (NCP) and the number of polymorphonuclear leukocytes (PMN) and mast cells were also assessed. In comparison with the tissue at time 0, we noted in the inflamed tissue (at 4 h) an increase in total proteins (4.

Decrease of ciliary beat frequency by platelet activating factor: protective effect of ketotifen.

The ciliary beat frequency (CBF) of the tracheal epithelial cells controls in part the respiratory tract mucociliary transport efficiency. We investigated the effects on CBF of PAF-acether (PAF) and its metabolite/precursor lyso-PAF. Guinea-pig tracheal rings were incubated for 3 to 6h with 1 microM PAF (C16, C18, C16/C18: 80/20%), lyso-PAF C16 or lyso-phosphatidylcholine (LPC).

Biochemical and cellular effects of heparin-protamine injection in rabbits are partially inhibited by a PAF-acether receptor antagonist.

The origin of the thrombocytopenia and leucopenia induced by protamine-heparin complexes is unknown. We studied the biochemical and cellular effects of protamine (6 mg x kg-1, i.v.

Regulation of platelet-activating factor production in gastric epithelial cells.

The authors have previously reported that platelet-activating factor (PAF), a phospholipid mediator with potent proinflammatory activities, is produced in the gastric mucosa and stimulates gastric acid secretion in humans and animals. In the present study they used the human gastric tumour cells HGT1 (clone 6) to examine whether PAF production is regulated by neuromediators. PAF was extracted by ethanol and assayed by the washed platelet aggregation test.

Liver and plasma concentrations in paf-acether and its precursors after partial hepatectomy.

Liver and plasma concentrations in paf-acether (paf) and related phosphocholines, i.e., lysopaf and the ether lipid 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholine (AAGPC) were studied in rats following two-third hepatectomy.

Intraluminal excretion of PAF, lysoPAF, and acetylhydrolase in patients with ulcerative colitis.

PAF-acether (PAF) is a phospholipid synthesized by numerous inflammatory cells. PAF can produce several pathological changes in various organs, especially in the colon. In animals PAF causes colonic ulceration and inflammation, which are similar to the anatomic lesions seen in human ulcerative colitis.

Inhibition of PAF-acether effects on isolated guinea pig hearts by zinc ions (Zn2+).

PAF-acether is a phospholipid synthesized by most animal tissues and exerting a strong decrease on the heart's contractile force and coronary flow. PAF-acether (10(-9) and 10(-10)M) was administered to isolated guinea pig hearts perfused via the Langendorff apparatus with Chenoweth solution. Zinc (1.

Studies on the surface properties of human lymphocytes by photon correlation spectroscopy technique.

Electrokinetic behaviour of human lymphocytes was studied by photon correlation spectroscopy technique on laser IR-spectrometer. The electrophoretic mobilities (EPMs) were measured for peripheral blood lymphocytes (PBL) and CEM-C12 T cell line in 1:1 electrolyte at 22 degrees C. Plots of mobility vs ionic strength in the range 0.

Human umbilical vein endothelial cells: specific binding of platelet-activating factor and cytosolic calcium flux.

An interaction of the platelet-activating factor (Paf) with endothelial cells was investigated using human umbilical vein endothelial cells. Confluent endothelial cells bound [3H]Paf in the presence of 0.25% fatty acid-free serum albumin after culture in media containing either heat-inactivated foetal calf serum or serum substitute.

Voltage-dependent ion channels on human basophils: do they exist?

The presence of voltage-dependent ion channels (particularly Ca2+ channels) on the surface of 'non excitable' cells such as human basophils is a matter of debate. Indeed, in basophils, Ca2+ entry or mobilization is not sufficient by itself to trigger secretion, although enhanced cytosolic Ca2+ concentration increases it. In order to address this question, we used a two-signal model and we report here experiments which suggest the presence of voltage-dependent structures directly or indirectly linked to membrane Ca2+ pathways.

Treatment of carrageenan induced arthritis by the platelet activating factor antagonist BN 50730.

Objective: To evaluate the role of platelet activating factor (PAF) in the early stage of arthritis.

Methods: Arthritis was induced in rabbits by weekly intra-articular injections of carrageenan. A PAF receptor antagonist, BN 50730, was used as a preventive or curative agent.

Correlations between PAF-acether and tumor necrosis factor in rheumatoid arthritis. Influence of parenteral corticosteroids.

The aim of this study was to evaluate the presence of PAF-acether (PAF), its specific degrading enzyme acetylhydrolase, and tumor necrosis factor (TNF) concentrations in blood and synovial fluid (SF) from patients with active RA. The variations of the mediators were also evaluated after corticosteroid perfusions in 7 patients. Lipo-PAF (PAF complexed to lipoproteins) was the main form of PAF detected both in blood and in SF, whereas unbound PAF was uncommon.

Modulation of stress proteins by Cd2+ in a human T cell line.

We previously showed in a human T cell line (CEM-C12 cells) that Cd2+ induced gene expression of stress proteins, metallothionein-IIA and heat shock protein 70 in a time- and dose-dependent manner. In the present study, CEM-C12 cells were pretreated for 24 h with 1 microM Cd2+ and then challenged with toxic concentrations of this metal. We found that maximal expression of the metallothionein-IIA and heat shock protein 70 genes was increased and this maximal level occurred at higher Cd2+ toxic concentrations.

Cadmium induces apoptosis in a human T cell line.

Cadmium, a potent toxic metal, poses a serious environmental threat but the mechanisms of its toxicity remain unclear. In the present study, we investigated the nature of cadmium-induced cell death in the human T cell line CEM-C12. Cadmium was time- and dose-dependently toxic for CEM-C12 cells, cell death being preceded by chromatin condensation and DNA fragmentation.

Anti-IgE induces the opening of non selective cation channels on human basophils.

Basophils play a major role in allergic reactions-particularly in late phase reactions-by releasing histamine and other mediators of inflammation. Although transmembrane ion fluxes are thought to play an important role in the modulation of histamine release, little is known about ion pathways through the basophil membrane. We thus studied human basophils from normal subjects (n = 25 cells) with the patch-clamp method.