Two competitive inhibitors of TAFIa (activated thrombin-activable fibrinolysis inhibitor), 2-guanidinoethylmercaptosuccinic acid and potato tuber carboxypeptidase inhibitor, variably affect fibrinolysis of clotted human plasma. Depending on their concentration, the inhibitors shortened, prolonged, or had no effect on lysis in vitro. The inhibitor-induced effects were both tissuetypeplasminogenactivator(tPA)andTAFIaconcentrationdependent. Inhibitor-dependent prolongation was favored at lower tPA concentrations. The magnitude of the prolongation increased with TAFIa concentration, and the maximal prolongation observed at each TAFIa concentration increased saturably with respect to TAFIa. A theoretical maximal prolongation of 20-fold was derived from a plot of the maximum prolongation versus TAFIa. This represents, for the first time, a measurement of the maximal antifibrinolytic potential of TAFIa in vitro.Because TAFIa spontaneously decays, the stabilization of TAFIa was investigated as a mechanism explaining the inhibitor-dependent prolongation of lysis. Both inhibitors stabilized TAFIa in a concentration-dependent, non-saturable manner. Although their K I values differed by three orders of magnitude, TAFIa was identically stabilized when the fraction of inhibitor-bound TAFIa was the same. The data fit a model whereby only free TAFIa decays. Therefore, the variable effects of competitive inhibitors of TAFIa on fibrinolysis can be rationalized in terms of free TAFIa and lysis time relative to the half-life of TAFIa.

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Objective. To establish the reliability, validity, and sensitivity to change of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) among Chinese subjects with osteoarthritis (OA) of the knee, living in mainland China. Methods. A multicenter, randomized, double-blind, placebo-controlled, parallel-group study was conducted for validation of the electronic personal digital assistant version of the WOMAC Numerical Rating Scale (NRS) 3.1 Index in China. A total of 287 subjects with OA of the knee were randomized to receive either meloxicam (15 mg) or placebo. Psychometric properties of the WOMAC were evaluated by estimating the reliability, validity, and sensitivity to change. Equivalence of the electronic version was also compared with the paper version. Results. Intraclass correlation coefficients for the WOMAC pain, stiffness, and physical function subscales were 0.81, 0.76, and 0.85, respectively, indicating good test-retest reliability. Similarly, internal consistency was strong (Cronbach's alpha for the 3 WOMAC subscales was 0.84, 0.86, and 0.96, respectively). Pearson's correlation coefficients for WOMAC pain and Short Form 36 health survey (SF-36) bodily pain, as well as WOMAC physical function and SF-36 physical functioning domains were >0.4, indicating convergent validity, whereas the coefficients for all 3 WOMAC domains with SF-36 mental health and mental health component scores were <0.4, indicating divergent validity. There was strong discriminant validity between healthy volunteers and OA patients. The effect sizes of change from baseline to week 12 in WOMAC subscale scores were large, demonstrating sensitivity to change. Equivalence between paper and electronic versions was very high. Conclusion. The culturally and linguistically validated Chinese version of the WOMAC NRS 3.1 for mainland China is psychometrically robust in its validity, reliability, and sensitivity to change for patients with OA of the knee.

1 Bradykinin can release neuronal calcitonin gene-related peptide (CGRP) and adrenal medullary catecholamines, both of which could contribute to its cardiovascular effects in vivo. Therefore, in the main experiment, regional haemodynamic responses to bolus injections of bradykinin (3 nmol kg- ', i.v.) were assessed in the same chronically-instrumented, conscious, Long Evans rats in the absence and in the presence of human a-CGRP or ICI 118551, antagonists of CGRPI-receptors and P2-adrenoceptors, respectively. The selected doses of these antagonists caused specific inhibition of responses mediated by exogenous human a-CGRP and P2-adrenoceptor agonists, respectively.2 Bradykinin administered alone as an i.v. bolus had a slight pressor effect accompanied by a marked tachycardia. There were early (at about 30 s) increases in flow and conductance in the mesenteric vascular bed, and delayed (at about 90 s), but qualitatively similar, changes in the hindquarters vascular bed. There were only slight increases in flow and conductance in the renal vascular bed. 3 Human a-CGRP had no statistically significant effects on the responses to bolus doses of bradykinin. However, in the presence of ICI 118551, the pressor effect of bradykinin was significantly enhanced while its tachycardic effect was significantly suppressed. The hindquarters vasodilator effect of bradykinin was converted to a vasoconstriction and there was a slight renal vasoconstriction, but the mesenteric vasodilator effect of bradykinin was unchanged by ICI 118551. 4 In subsidiary experiments, in other animals, it was found that infusion of bradykinin (36 nmol kg-' min-') elicited a pattern of haemodynamic responses similar to that seen with bolus injections and, as in the latter case, the hindquarters hyperaemic vasodilatation was inhibited by ICI 118551. In the presence of mecamylamine (at a dose sufficient to block reflex heart rate responses to rises or falls in arterial blood pressure) bolus injection or infusion of bradykinin still elicited increases in renal, mesenteric and hindquarters blood flow. However, in additional experiments in adrenal demedullated rats (n = 4) the hindquarters hyperaemic effect of bradykinin was absent, although the mesenteric hyperaemic effect remained. 5 The results indicate that the increase in hindquarters blood flow following administration of bradykinin in vivo is largely due to activation of P2-adrenoceptors by catecholamines released subsequent to direct stimulation of the adrenal medulla by the peptide. However, the bradykinin-induced increase in mesenteric blood flow does not depend on this mechanism.

1 The novel tri-aryl ethane CDP840, is a potent and selective inhibitor of cyclic AMP phosphodiesterase type 4 (PDE 4) extracted from tissues or recombinant PDE 4 isoforms expressed in yeast (IC,,. CDP840 is stereo-selective since its S enantiomer (CT 1731) is 10-50 times less active against all forms of PDE 4 tested while both enantiomers are inactive (IC50s: > 100 gM) against PDE types 1, 2, 3 and 5.2 Oral administration of CDP840 caused a dose-dependent reduction of interleukin-5 (IL-5)-induced pleural eosinophilia in rats (ED50=0.03 mg kg-'). The eosinophils in pleural exudates from CDP840-treated animals contained higher levels of eosinophil peroxidase (EPO) than cells from control animals, suggesting a stabilizing effect on eosinophil degranulation. CDP840 was approximately equi-active with the steroid dexamethasone in this model and was 10-100 times more potent than the known PDE 4-selective inhibitors rolipram and RP73401. The activity of CDP840 was not influenced by adrenalectomy, ,B-sympathomimetics or ,B-sympatholytics. 3 Antigen-induced pulmonary eosinophilia in sensitized guinea-pigs was reduced dose-dependently by CDP840 (0.01 -1 mg kg-', i.p.) and intracellular EPO levels were significantly higher. CDP840 was more potent in these activities than CT1731 or rolipram and comparable in potency to RP73401. 4 Rolipram or CDP840 were less active than dexamethasone in preventing neutrophil accumulation, or exudate formation in carrageenan-induced pleurisy in rats and thus do not exhibit general antiinflammatory activity. 5 In sensitized guinea-pigs, aerosols of the antigen ovalbumin caused a dose-dependent bronchoconstriction demonstrated by an increase in pulmonary inflation pressure. Administration of CDP840 (0.001 -1.0 mg kg-', i.p.), 1 h before antigen challenge, resulted in dose-dependent reduction in response to antigen. This activity was not due to bronchodilatation since higher doses of CDP840 (3 mg kg-') did not significantly change the bronchoconstrictor response to histamine. Rolipram was approximately 10 times less active than CDP840 in preventing antigen-induced bronchoconstriction. 6 These results confirm the observations that selective PDE 4 inhibitors reduce antigen-induced bronchoconstriction and pulmonary eosinophilic inflammation. CDP840 is more potent than rolipram in inhibiting native or recombinant PDE 4. Unlike the recently described potent PDE 4 inhibitor RP73401, CDP840 is more active than rolipram in the rat IL-5 model following oral administration. The novel series of tri-aryl ethanes, of which CDP840 is the lead compound, could be the basis of an orally active prophylactic treatment for human asthma.