Search results for " erythrocytes"
showing 10 items of 12 documents
Modulating effects of humic acids on genotoxicity induced by water disinfectants in Cyprinus carpio
2005
The use of chlorinated disinfectants during drinking-water production has been shown to generate halogenated compounds as a result of interactions of humic acids with chlorine. Such chlorinated by-products have been shown to induce genotoxic effects and consumption of chlorinated drinking-water has been correlated with increased risk for cancer induction in human populations. The aim of this work was to test the potential genotoxic effects on circulating erythrocytes of the fish Cyprinus carpio exposed in vivo to well-waters disinfected with sodium hypochlorite (NaClO), chlorine dioxide (ClO2) or peracetic acid (CH3COO2H, PAA), in the absence or presence of standard humic acids (HA). The ef…
Sphingomyelin inhibition of Ciona intestinalis (Tunicata) cytotoxic hemocytes assayed against sheep erythrocytes
1995
Hemocytes from the ascidian, Ciona intestinalis, are capable of lysing erythrocytes in vitro following cell membrane contact. With the aim of examining the mechanism of cytotoxicity, we performed inhibition experiments with lipid components of erythrocyte membranes. Cholesterol is not an inhibitor, whereas, among the phospholipids tested, (sphingomyelin, phosphatidylcholine, phosphatidylserine, phosphatidylethanolamine) sphingomyelin inhibits the hemolytic activity of hemocytes. However, thin layer chromatography showed that sphingomyelinase activity was not contained in the chloroform-methanol extracts from hemocyte debris. The inhibition capacity of the components ceramide and phosphorylc…
Dietary indicaxanthin from cactus pear (Opuntia ficus-indica L. Mill) fruit prevents eryptosis induced by oxysterols in a hypercholesterolaemia-relev…
2015
Toxic oxysterols in a hypercholesterolaemia-relevant proportion cause suicidal death of human erythrocytes or eryptosis. This process proceeds through early production of reactive oxygen species (ROS), release of prostaglandin (PGE2) and opening of PGE2-dependent Ca channels, membrane phosphatidylserine (PS) externalisation, and cell shrinkage. The present study was the first to reveal that a bioavailable phytochemical, indicaxanthin (Ind) from cactus pear fruit, in a concentration range (1·0–5·0 μM) consistent with its plasma level after a fruit meal, prevents PS externalisation and cell shrinkage in a dose-dependent manner when incubated with isolated healthy human erythrocytes exposed to…
AN IL-6/IL-6 SOLUBLE RECEPTOR (IL-6R) HYBRID PROTEIN (H-IL-6) INDUCES EPO-INDEPENDENT ERYTHROID DIFFERENTIATION IN HUMAN CD34+CELLS
2000
H-IL-6 is a hybrid protein constructed to contain IL-6 and its soluble receptor linked by a flexible peptide chain. Here we show that H-IL-6 strongly enhances proliferation of human CD34(+)cells in serum-free liquid culture, and that the majority of the cells generated belong to the erythroid lineage, being positive for the marker Glycophorin A. Conversely, H-IL-6 does not increase the number of myeloid, CD13-positive cells. Comparable effects are observed on progenitors from cord blood and adult peripheral blood. Therefore, H-IL-6 triggers an erythroid-inducing signal in haematopoietic progenitor cells, independently from erythropoietin (EPO).
Enhancement of the Mutagenicity of Ethylene Oxide and Several Directly Acting Mutagens by Human Erythrocytes and its Reduction by Xenobiotic Interact…
1999
According to the present state of knowledge mutagenicity or genotoxicity of the ulti mate genotoxic agents ethylene oxide or styrene oxide cannot be increased by further me tabolism. However, in the present study we demonstrate that mutagenicity of several ultimate genotoxic substances is increased by human erythrocytes. For instance mu tagenicity of mafosfamide, N-nitroso-N-methylurea, ethylene oxide, and styrene oxide to Salmonella typhimurium TA 1535 was increased 5.5-, 5.1-, 2.7-, and 2.3-fold, respectively, by addition of human erythrocyte homogenate to the preincubation mixture in the Ames test. On the other hand, the mutagenicity of cumene hydroperoxide, benzo[a]pyrene-4,5-oxide, and…
Presence of calreticulin mutations in JAK2-negative polycythemia vera
2014
Abstract Calreticulin (CALR) mutations have recently been reported in JAK2- and MPL-negative Myeloproliferative Neoplasms (MPN), particularly essential thrombocythemia (ET) and primary myelofibrosis (PMF).The clinical course of sporadic CALR-mutated patients seems to be more indolent than that of JAK2-mutated patients. In contrast, no CALR mutation has been found in the 647 published cases of Polycythemia Vera (PV) patients tested. Consequently, CALR mutations were considered exclusive to JAK2 and MPL mutations. Since 98% of PV patients harbor a JAK2 mutation (mostly the V617F mutation in exon 14 and more rarely, in exon 12), the absence of CALR mutations in PV seemed logical. Here, we desc…
Untersuchungen über den Einfluß langkettiger fettsaurer Salze auf Erythrozyten
1969
Natrium-oleat und Olsaure haben spezifische morphologische und funktionelle Wirkungen auf menschliche Erythrozyten in vitro. Eine Erhohung der Konzentration dieser Substanzen im Blut fuhrt zu reversiblen stechapfelformigen Veranderungen der Erythrozytenform, zur Hemmung der Blutkorperchensenkungsgeschwindigkeit und zur Senkung der Strukturviskositat des Blutes. Weiterhin wird bei Konzentrationen bis 45 mg% die osmotische Resistenz der Erythrozyten verbessert. Erst hohe Konzentrationen an Na-oleat im Blut fuhren zur Hamolyse. Investigations on the Influence of Long Chain Fatty Acid Salts on Erythrocytes Sodium oleate and oleic acid have specific morphological and functional action on human e…
Pertuzumab monotherapy after trastuzumab-based treatment and subsequent reintroduction of trastuzumab: activity and tolerability in patients with adv…
2012
Purpose The combination of pertuzumab and trastuzumab resulted in a clinical benefit rate (CBR) of 50% in patients with human epidermal growth factor receptor 2 (HER2) –positive breast cancer whose disease progressed during prior trastuzumab-based therapy. To define whether this previously observed encouraging activity was a result of the combination of pertuzumab and trastuzumab or of pertuzumab alone, we recruited a third cohort of patients who received pertuzumab without trastuzumab. We then investigated the impact of reintroducing trastuzumab to patients whose disease progressed on pertuzumab monotherapy. Patients and Methods Twenty-nine patients with HER2-positive breast cancer whose d…
Der erythrocytäre Magnesiumstoffwechsel bei intakter und kälteinhibierter Glykolyse
1962
Continuation of glycolysis in human erythrocytes by incubation of heparinized whole blood at 37°C is followed by a decrease in the Mg-content of red cells. On inhibition of glycolysis by cold (4°C), the Mg-content of erythrocytes remains unaltered or, often, slightly increases. These actions are in clear contrast to the behaviour of potassium ions under the same conditions.
Influence of spurious dilution and hyperglycemia on erythrocytes and platelets evaluated with two different hematological analyzers
2015
The integrity of whole blood samples may be compromised by suboptimal collection practices. Therefore, we investigated the influence of spurious hyperglycemia on erythrocytes and platelets, assessed with two hematological analyzers using optical or impedance technique. Three K2EDTA blood specimens were collected from 12 healthy subjects, pooled and divided into four aliquots. The first aliquot was left untreated (glucose concentration 4.4 mmol/L), whereas scalar amounts of standard 5% glucose solution were added to the remaining, generating glucose contamination of 5% (19.2 mmol/L), 10% (33 mmol/L) and 20% (62 mmol/L). Hematological testing was then performed using Siemens Advia 2120 and Sy…