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Do smoking and diabetes change the hemostatic parameters?--a study in the Chinese people.

Plasma plasminogen activator inhibitor-1 (PAI) antigen, fibrinogen, antithrombin III (ATIII), protein C, beta-thromboglobulin (BTG), platelet count, fibrinogen degradation product (FDP) D-dimer, factors VII and XII, as well as cholesterol, triglyceride (TG) and glucose were determined in 163 subjects. First we compared the difference of these parameters between 50 diabetics (Group D, mean age 64.9 years) and 50 age-matched healthy controls (Group C, mean age 63.1 years). Nineteen of the diabetics and 19 of the healthy controls were smokers. Plasma glucose, cholesterol, TG and protein C were significantly higher in Group D than in Group C (p = 0.0010, 0.0308, 0.0083 and 0.0068, respectively), whereas ATIII and factor XII were significantly lower in Group D (p = 0.0213 and 0.0061). Secondly, we divided 113 healthy controls (Group C, including Group C plus 63 subjects at various ages) into smokers (mean age 56.7 years) and non-smokers (mean age 40.0 years) and compared the difference between them. Fibrinogen and glucose were higher in the smokers than in the non-smokers (p = 0.0139 and 0.0402, respectively). Other parameters were not different. In conclusion, our study did not find any important hypercoagulation state in the diabetics. Smoking can only increase fibrinogen and glucose without the change of other hemostatic parameters.

Adult↗

Molecular evolution and domain structure of plasminogen-related growth factors (HGF/SF and HGF1/MSP).

Plasminogen-related growth factors, a new family of polypeptide growth factors with the basic domain organization and mechanism of activation of the blood proteinase plasminogen, include hepatocyte growth factor/scatter factor (HGF/SF), a potent effector of the growth, movement, and differentiation of epithelia and endothelia, and hepatocyte growth factor-like/macrophage stimulating protein (HGF1/MSP), an effector of macrophage chemotaxis and phagocytosis. Phylogeny of the serine proteinase domains and analysis of intron-exon boundaries and kringle sequences indicate that HGF/SF, HGF1/MSP, plasminogen, and apolipoprotein (a) have evolved from a common ancestral gene that consisted of an N-terminal domain corresponding to plasminogen activation peptide (PAP), 3 copies of the kringle domain, and a serine proteinase domain. Models of the N domains of HGF/SF, HGF1/MSP, and plasminogen, characterized by the presence of 4 conserved Cys residues forming a loop in a loop, have been modeled based on disulfide-bond constraints. There is a distinct pattern of charged and hydrophobic residues in the helix-strand-helix motif proposed for the PAP domain of HGF/SF; these may be important for receptor interaction. Three-dimensional structures of the 4 kringle and the serine proteinase domains of HGF/SF were constructed by comparative modeling using the suite of programs COMPOSER and were energy minimized. Docking of a lysine analogue indicates a putative lysine-binding pocket within kringle 2 (and possibly another in kringle 4). The models suggest a mechanism for the formation of a noncovalent HGF/SF homodimer that may be responsible for the activation of the Met receptor. These data provide evidence for the divergent evolution and structural similarity of plasminogen, HGF/SF, and HGF1/MSP, and highlight a new strategy for growth factor evolution, namely the adaptation of a proteolytic enzyme to a role in receptor activation.

Amino Acid Sequence↗

Coagulation abnormalities in type 1 Gaucher disease are due to low-grade activation and can be partly restored by enzyme supplementation therapy.

In type 1 Gaucher disease a bleeding tendency occurs which is partly caused by thrombocytopenia due to massive splenomegaly. In addition, low levels of factors IX and XI have been described. The mechanism responsible for these clotting factor abnormalities is unknown. We performed a detailed study of parameters of coagulation and fibrinolysis in 30 type 1 Gaucher disease patients (14 splenectomized) before and after treatment with enzyme supplementation therapy. Pre-treatment aPTT and PT were prolonged in 42% and 38% of patients, respectively. In 30-60% serious deficiencies (< 50%) of coagulation factors XI, XII, VII, X, V and II were observed. The low levels of factor V correlated with platelet count and were inversely associated with splenic volume. Levels of inhibitors were mildly decreased. Markers for activation of coagulation (thrombin-antithrombin (TAT) complex) and fibrinolysis (PAP complex, fibrin cleavage product D-dimer) were significantly elevated, especially in the splenectomized patients, indicating ongoing activation of these processes. After 12 months of enzyme supplementation therapy partial correction occurred. Thus, severe disorders of the coagulation system occur in Gaucher disease, contributing to the bleeding tendency. The deficiencies may be the result of consumption of coagulation factors caused by ongoing low-level coagulation activation. possibly due to mononuclear cell activation.

Adult↗

Effects of extended storage of whole blood before leucocyte depletion on coagulation factors in plasma.

BACKGROUND AND OBJECTIVES: The aim of this study was to evaluate the quality of leucocyte-depleted plasma produced from leucocyte-depleted whole blood, stored for different periods of times before filtration through polyurethane filters. MATERIALS AND METHODS: Whole blood was collected, from 48 voluntary donors, into quadruple blood bag sets with integrated whole-blood filters, and stored at room temperature for 1, 2, 6, or 18 h before filtration. Five samples were taken: one directly from the donor; one immediately after collection; one before and one after filtration; and one from plasma units before freezing. All samples were analysed for the following parameters: prothrombin time; activated partial thromboplastin time; prothrombin fragments F1+2; fibrinogen; factors VIII, XI and XII; von Willebrand factor antigen; ristocetin cofactor activity; collagen-binding capacity; multimers; and complement C3a-desArg. RESULTS: Different whole-blood storage times before filtration did not have a significant effect on the stability of coagulation factors. The activity of all investigated coagulation factors in plasma was generally above 90 U/dl, even after 18 h of storage of whole blood before filtration. von Willebrand factor multimeric distribution remained stable throughout the process. However, activation of complement did occur during storage. CONCLUSIONS: Leucodepleted plasma originating from leucodepleted whole blood maintains a satisfactory level of coagulation factors, even after the storage of whole blood for 18 h at room temperature before filtration.

Adult↗

[Prevalence of prolonged APTT and lupus anticoagulant in autoimmune thyroid disease].

We describe prevalences of prolonged activated partial thromboplastin time(APTT) and lupus anticoagulant(LAC) in autoimmune thyroid disease(AITD). Prolonged APTTs were observed in 33(6.2%) blood samples out of 532 AITD cases(327 Graves' diseases and 205 Hashimoto's thyroiditis), but in only 8(2.0%) samples out of 396 non AITD cases(213 thyroid tumors, 14 subacute thyroiditis and 169 normal thyroids). The samples with prolonged APTT showed no abnormality in coagulation factors(factor VIII, IX, XI, XII, von Willebrand factor(vWF), prekallikrein, or high molecular weight kininogen) or factor VIII, IX inhibitor. Among samples with prolonged APTT, LAC evaluated by platelet neutralization procedure(PNP) was positive in 17(51.5%) samples of AITD, and in 2(25.0%) samples of non AITD. In prolonged APTT cases, the frequency of fetal loss in patients with AITD was higher than non AITD patients. But no significant difference was obtained between thyroid autoimmune antibody and the frequency of fatal loss. These indicate unknown biological association of between AITD and LAC.

Abortion, Spontaneous↗

Complement activation in human lymph: modulation by the contact activation system and by leukocytes.

Complement components, their activation and the generation of C3a and C5a peptides were studied in human lymph used as a model of tissue fluid. Both, classical and alternative pathways could be activated by suitable agents such as immune aggregates or zymosan. C3 activation and C3a formation were marked while only 10-15% of the anyway low amount of C5 were converted during complement activation, yielding very low concentrations of C5a. Carboxypeptidase N activity was present in lymph and converted the peptides to their less (C5a) or not at all (C3a) active desArg derivatives. Contact activation of Hageman factor and kallikrein enhanced activation of the classical pathway up to C3 conversion. The search for additional processes apt to create efficient concentrations of C5a (desArg) in lymph led to the discovery that the presence of leukocytes in lymph greatly increases the release of C5a activity upon complement activation. This suggests a physiological role of leukocytes resident in tissues for the induction of inflammatory reactions.

Anaphylatoxins↗

Release of platelet constituents by monosodium urate crystals.

The release of human platelet constituents by the etiologic agent of gout, the monosodium urate crystal, is described here. In suspensions of washed platelets, response to urate crystals proceeded in two phases: A secretory phase involved the rapid active release of serotonin, ATP, and ADP with little loss of lactic dehydrogenase or beta-glucuronidase. A lytic phase involved the slower loss of all platelet constituents. Both phases were inhibited by iodoacetate plus dinitrophenol, suggesting an energy requirement. In ultrastructural studies, lysis of washed platelets which appeared to contain crystals was seen. Urate crystals were also shown to induce serotonin release and platelet lysis in citrated platelet-rich plasma. Since urate crystals are deposited at a variety of sites, urate crystal-platelet interaction in vivo is a possibility. Such interactions, leading to release of platelet constituents, might contribute to gouty inflammation or to enhanced atherogenesis.

Blood Platelets↗

Studies on components of the plasma kallikrein system as a risk factor in diabetics undergoing cardiopulmonary bypass.

Components of the FX11-kallikrein systems were determined in blood samples from non diabetics and diabetics undergoing cardiopulmonary bypass (CPB). FX11 and prekallikrein levels fell in both groups with the largest falls in the diabetic group. Kallikrein inhibition was also lower in the diabetic group. Alpha-2-macroglobulin levels were lower in the diabetic group before operation and were markedly lower throughout CPB. Kallikrein like activities were also lower in the diabetic group. Beta FX11a inhibition values were higher in the diabetic group and fell in both groups during CPB. From the results obtained we concluded that the lower levels of FX11, prekallikrein, kallikrein inhibition and alpha-2-macroglobulin in the diabetic patients during CPB reflect enhanced activation of the FX11-plasma kallikrein systems. Blood loss in the diabetic group was higher than the for non diabetic group.

Biomarkers↗

[Articular inflammation of microcrystalline origin].

Microcrystals of sodium urate, calcium pyrophosphate, hydroxyapatite and corticosteroids may induce acute arthritis by similar mechanisms in which neutrophils play the most important role. Interactions between neutrophils and microcrystals result in the release of several phlogogenic substances, e.g. lysosomal enzymes, chemotactic factor (CCF) or leukotrienes. Various proteins may be adsorbed to the surface of microcrystals, and this protein coating seems to be instrumental in modulating the neutrophil-microcrystal interaction. The Hageman factor and the complement system may also be activated. The mechanisms starting off and resolving articular attacks are discussed.

Acute Disease↗

Inflammatory mediators and acute infections.

In this paper some important mediation systems of inflammation are reviewed; special emphasis is laid on basic aspects of these systems, their interrelationships, and on clinically relevant effects with regard to the circulatory and pulmonary complications of sepsis. The references cited are selected on the basis of their review aspects.

Arachidonic Acid↗