Neutrophils can Promote Clotting via FXI and Impact Clot Structure via Neutrophil Extracellular Traps in a Distinctive Manner in vitro

Neutrophils and neutrophil extracellular traps (NETs) have been shown to be involved in coagulation. However, the interactions between neutrophils or NETs and fibrin(ogen) in clots, and the mechanisms behind these interactions are not yet fully understood. In this in vitro study, the role of neutrophils or NETs on clot structure, formation and dissolution was studied with a combination of confocal microscopy, turbidity and permeation experiments. Factor (F)XII, FXI and FVII-deficient plasmas were used to investigate which factors may be involved in the procoagulant effects. We found both neutrophils and NETs promote clotting in plasma without the addition of other coagulation triggers, but not in purified fibrinogen, indicating that other factors mediate the interaction. The procoagulant effects of neutrophils and NETs were also observed in FXII- and FVII-deficient plasma. In FXI-deficient plasma, only the procoagulant effects of NETs were observed, but not of neutrophils. NETs increased the density of clots, particularly in the vicinity of the NETs, while neutrophils-induced clots were less stable and more porous. In conclusion, NETs accelerate clotting and contribute to the formation of a denser, more lysis resistant clot architecture. Neutrophils, or their released mediators, may induce clotting in a different manner to NETs, mediated by FXI

Diagnostic et traitement de la carence en fer sans anémie [Diagnosis and treatment of iron deficiency without anaemia]

Iron deficiency (ID) without anaemia frequently remains undiagnosed when symptoms are attributed to ID with anaemia. Serum ferritin is the primary diagnostic parameter, whereas <10 microg/l represent depleted iron stores, 10-30 microg/l can confirm ID without anaemia and 30-50 microg/l might indicate functional ID. In case of increased CRP or ALT, normal/elevated ferritin should be interpreted with caution. IV iron is indicated if oral iron is not effective or tolerated. At ferritin <10 microg/l, a cumulative dose of 1000 mg iron and at ferritin 10-30 microg/l, a cumulative dose of 500 mg is advised. At ferritin 30-50 microg/l a first dose of 200 mg might be considered. Ferritin shall be reassessed not sooner than 2 weeks after the last oral or 8-12 weeks after the last IV iron administration

Diagnose und Behandlung von Eisenmangel ohne Anämie

Eisenmangel ohne Anämie bleibt oft undiagnostiziert, da die Symptome einem Eisenmangel mit Anämie zugeschrieben werden. Serumferritin ist der beste diagnostische Parameter, wobei <10 μg/l eine erschöpfte Eisenreserve widerspiegeln, 10-30 μg/l einen Eisenmangel ohne Anämie bestätigen können und bei 30-50 μg/l ein funktioneller Eisenmangel möglich ist. Sind CRP oder ALT erhöht, ist normales/erhöhtes Ferritin mit Vorsicht zu interpretieren. Parenterale Eisenbehandlung ist indiziert, falls die primäre orale Eisentherapie nicht erfolgreich ist oder nicht toleriert wird. Bei Ferritin <10 μg/l ist eine kumulative Gesamtdosis von 1000 mg Eisen vorzusehen, bei 10-30 μg/l ist eine kumulative Gesamtdosis von 500 mg empfohlen, und bei 30-50 μg/l kann eine erste Dosis von 200 mg verabreicht werden. Ferritin soll frühestens zwei Wochen nach der letzten oralen bzw. 8-12 Wochen nach der letzten parenteralen Verabreichung nachkontrolliert werden. = Iron deficiency (ID) without anaemia frequently remains undiagnosed when symptoms are attributed to ID with anaemia. Serum ferritin is the primary diagnostic parameter, whereas <10 μg/l represent depleted iron stores, 10-30 μg/l can confirm ID without anaemia and 30-50 μg/l might indicate functional ID. In case of increased CRP or ALT, normal/elevated ferritin should be interpreted with caution. Intravenous iron is indicated if oral iron is not effective or tolerated. At ferritin <10 μg/l, a cumulative dose of 1000 mg iron and at ferritin 10-30 μg/l, a cumulative dose of 500 mg is advised. At ferritin 30-50 μg/l a first dose of 200 mg might be considered. Ferritin shall be reassessed not sooner than 2 weeks after the last oral or 8-12 weeks after the last iv iron administration. = La carence en fer (CF) sans anémie reste souvent non diagnostiquée car les symptômes sont attribués à l’anémie ferriprive. La ferritine en est le marqueur le plus spécifique: <10 μg/l représente des réserves épuisées, 10-30 μg/l peuvent confirmer une CF, 30-50 μg/l peuvent indiquer une CF fonctionnelle. Si les valeurs de CRP et d’ALAT sont élevées, il faut interpréter une valeur de ferritine élevée/normale avec précaution. Si un traitement oral n’apporte pas le succès escompté ou n’est pas toléré par le patient, un traitement intraveineux est justifié. Chez les patients présentant une ferritine <10 μg/l, l’administration d’une dose cumulative totale de 1000 mg de fer doit être envisage. Pour une ferritine de 10-30 μg/l, on préconise une dose cumulative totale de 500 mg de fer. Pour une ferritine de 30-50 μg/l, on peut administrer une première dose de 200 mg de fer. La ferritine doit être contrôlée au plus tôt 2 semaines après le dernier traitement par voie orale ou 8-12 semaines après la dernière injection par voie intraveineuse

ELISA for quantitation of L-selectin shed from leukocytes in vivo

L-selectin is a cell surface receptor on granulocytes, lymphocytes and monocytes that is responsible for the initial attachment of leukocytes to endothelium. The extracellular domain of L-selectin is proteolytically shed from leukocytes following cellular activation in vitro. The shed form of L-selectin (SL-selectin) is functionally active and at high concentrations can inhibit leukocyte attachment to endothelium. Therefore, an ELISA was developed to quantitate the levels of SL-selectin in biological fluids, biopsy specimens and during recombinant protein production. This simple, quantitative sandwich ELISA uses two monoclonal antibodies directed against the extracellular domain of SL-selectin. The assay has a detection range of 5-1300 ng/ml, is precise and sensitive. The ability of this assay to detect SL-selectin in serum, plasma, and culture supernatant fluid was demonstrated and it was used to quantitate circulating SL-selectin in normal and patient sera. Patients with sepsis and HIV infection showed markedly elevated SL-selectin levels in serum. Thus, the ELISA should prove useful both for laboratory purposes as well as in the diagnostic evaluation of patients with inflammatory diseases

Determinants of inter-individual cholesterol level variation in an unbiased young male sample

Copyright © 2008 EMH Swiss Medical Publishers Ltd.Question under study: Affected by individual life style, the total cholesterol serum level is a major morbidity and mortality risk factor for atherosclerotic cardiovascular disease (CVD). We present total cholesterol values and their possible aetiological factors of young Swiss conscripts. Particularly, we study varying impact of these factors depending on different levels of individual cholesterol. Methods: Male conscripts (n = 19,272) of the 2005 census of the conscripts have been examined, reflecting ca. 59% of a total Swiss male birth cohort. Quantile regression allows us to analyse responses of arbitrary quantiles with respect to variables of interest. Results: Eleven percent of all conscripts show clinically important increased total cholesterol levels. There is a major association of high individual cholesterol level with French regional language. The largest socio-economic subsample – agricultural and construction workers – show significantly higher individual cholesterol levels than employees in the industry sector and students, respectively. Conclusions: We were able to find that culture, as indicated by the mother tongue, and socioeconomic status as indicated by profession/vocation, influence individual total cholesterol levels while climate as indicated by altitude does not have an influence on cholesterol levels. Such a broad screening programme offers a unique opportunity to target persons at high-risk for CVD morbidity and mortality already early in life.Rühli FJ, Henneberg M, Schär DJ, Imhof A, Schleiffenbaum B, Woitek U