Extracellular targeting of choline-binding proteins in Streptococcus pneumoniae by a zinc metalloprotease.

A genetic-based search for surface proteins of Streptococcus pneumoniae involved in adhesion identified a putative zinc metalloprotease (ZmpB). ZmpB shared high amino acid sequence similarities with IgA1 proteases of Gram-positive bacteria, but ZmpB had neither IgA1 nor IgA2 protease activity. Analysis of a family of surface-expressed proteins, the choline-binding proteins (Cbp's), in a zmpB-deficient mutant demonstrated a global loss of surface expression of CbpA, CbpE, CbpF and CbpJ.

Pharmacokinetics and tolerability of factor XIII concentrates prepared from human placenta or plasma: a crossover randomised study.

The pharmacokinetics and tolerability of factor XIII (FXIII) from plasma were compared with those of FXIII from placenta in a randomised, double-blind, crossover study involving 13 patients with congenital FXIII deficiency. Both FXIII activity and FXIII antigen were monitored. No difference was seen in the mean half-lives of the two preparations (9.

Quality control in haemostasis.

Laboratory investigation of the haemostatic system deserves particular procedures in the quality control of analytical variables as well as preanalytical variables. This paper reviews the precautions that have to be taken in the blood prelevement, the transport of the tubes and the performance of the laboratory tests aimed to investigate the haemostatic system in order to obtain reliable results.

[Depot medroxyprogesterone acetate: clinical and metabolic effects (lipids, glucose, hemostasis)].

Medroxyprogesterone acetate (MPA), a potent progestagen, is used as a very efficient contraceptive agent. The method of administration is by a threemonthly or sixmonthly intramuscular injection. The method is particularly convenient when the desired number of children has been reached.

Haemostasis disorders in open heart surgery with extracorporeal circulation. Importance of the platelet function and the heparin neutralization.

The main haemostasis changes observed in a screening study performed in 40 patients who underwent an open heart surgery with extracorporeal circulation (ECC) are: a significant drop in platelet count from the onset of the ECC to the third postoperative day, a decrease of platelet retention and aggregation during ECC with an 8-day persistently increased heparin-neutralizing activity in plasma but not in serum, a moderate decrease of plasma factors I, II, VII-X, X and XIII and a more important drop in factor V which disappears 24 h after ECC, a transitory increase of fibrinolysis during ECC and the lack of FDP elevation in the serum. These disorders require a very good neutralization of the heparin used during ECC. The ratio protamine/heparin can be established by a titration clotting time test.

Comparative effects of proteinase inhibitors, plasminogen antiactivators, heparin and acetylsalicylic acid on the experimental disseminated intravascular coagulation induced by thormbin.

In an experimental study in the rabbit, the modifications of some haemostasis parameters (platelet count, platelet retention and aggregation, platelet factors 3 and 4, platelet and plasma plasmin inhibiting activities, fibrinogen and other plasma factor levels, FDP), and histological findings are compared in both the normal animal and the animal with disseminated intravascular coagulation (DIC) induced by thrombin perfusion after administration of fibrinolytic inhibitors (plasminogen antiactivators and proteinase inhibitors). In the normal animal, the administration of fibrinolytic inhibitors is followed by haemostatic changes similar to those found in thrombophilic states. The modifications are more pronounced with plasminogen antiactivators than with proteinase inhibitors.

Effects of alpha and beta receptor stimulating and blocking agents on experimental disseminated intravascular coagulation.

In this experimental study on rabbits, we compare the haemostatic and histological changes observed in animals with disseminated intravascular coagulation (DIC) induced by thrombin perfusion (100 u/kg/hr during 3 hours) with or without preventive administration of alpha and beta receptor stimulating or blocking agents. Both alpha and beta receptor stimulating agents enhance the disorders induced by thrombin alone, while alpha or beta blocking agents reduce them. This favourable action is still more pronounced with the combination of these two last types of drugs.