Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We performed a cross-sectional case-control study among 277 subjects with dementia and 298 control subjects drawn from participants of the Rotterdam Study, a population-based cohort study among subjects aged 55 years or over, and from participants of the Rotterdam Stroke Databank, a hospital-based stroke registry, with the objective to evaluate the association of indicators of coagulability, fibrinogen, prothrombin fragments 1+2, thrombin-antithrombin complex (TAT), and indicators of fibrinolysis, plasmin-inhibitor complex, D-dimer and tissue-type plasminogen activator (t-PA) with dementia. Increased levels of TAT, D-dimer and t-PA activity were associated with an increased risk of dementia. Additional stratified analyses indicated that an increased TAT level was the primary factor related to dementia. The present study provides evidence that predominantly increased thrombin generation is associated with dementia.
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PMID:Coagulation and fibrinolysis markers and risk of dementia. The Dutch Vascular Factors in Dementia Study. 1042 69

We constructed a hirudin cDNA cassette, HV-1.1, that encodes mature hirudin variant-1 fused to the signal peptide of human tissue-type plasminogen activator (t-PA). The cassette was subcloned into retroviral vectors and used to transduce human vascular endothelial cells in vitro. Hirudin antigen and activity were measured by ELISA and thrombin inhibition assays, respectively. Transduced cells secreted up to 35 +/- 2 ng/10(6) cells/24 h of biologically active hirudin; expression was stable for at least 7 weeks. Recombinant hirudin, expressed from the HV-1.1 cassette, had a specific activity of 7.1 +/- 0.2 antithrombin units per microgram (ATU/microgram), compared with specific activities of approximately 12 ATU/microgram for both native leech hirudin and recombinant hirudin produced in yeast. Protein sequencing and mass spectroscopic analysis revealed the presence of an extra N-terminal serine residue, indicating aberrant cleavage of the t-PA signal peptide and likely accounting for the diminished activity. We therefore constructed a second cDNA cassette, HV-1.2, in which hirudin secretion was directed by the signal peptide of human growth hormone. Hirudin expressed from the HV-1.2 cassette had a specific activity of 13.5 +/- 0.2 ATU/microgram. Protein sequencing and mass spectroscopic analysis demonstrated proper cleavage of the growth hormone signal peptide. Thus, we achieved high level retrovirus-mediated secretion of biologically active hirudin from endothelial cells in vitro. Use of these vectors may permit sustained local antagonism of thrombin activity in vivo.
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PMID:Retroviral vector-mediated expression of hirudin by human vascular endothelial cells: implications for the design of retroviral vectors expressing biologically active proteins. 1043 88

Although fibrinolysis has been implicated in the progression and metastasis of lung cancer, no detailed study has been carried out on components measured in samples from both plasma and tumour. This study thus provides the first comprehensive data obtained from 166 patients diagnosed with non-small cell lung carcinoma. Plasma samples were obtained at diagnosis and tumour samples during surgical resection. Appropriate control samples were obtained from normal subjects and patients with chronic obstructive airways disease (plasma) and from organ donors (normal lung tissue). Assays were performed on plasma and tissue extracts for tissue plasminogen activator, urokinase-like activator and plasminogen activator inhibitor (activity and antigen in all cases), together with plasmin-antiplasmin complex, soluble fibrin, D-dimer and thrombin-antithrombin complex. Levels of D-dimer, thrombin-antithrombin complex and plasmin-antiplasmin complex were all significantly higher in plasma from patients, whereas urokinase-like activator activity was reduced. Only two parameters were significantly altered in both the core and periphery of tumour tissue: levels of D-dimer were increased and tissue-type plasminogen activator activity was reduced. Interestingly, significant differences in levels of other fibrinolytic parameters were detected in the core and periphery of tumours. Significant activation of fibrinolysis was indicated in patients, although the origin of this could not be related consistently to changes in levels of plasminogen activator and inhibitor.
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PMID:Alterations to the fibrinolytic enzyme system in patients with non-small cell lung carcinoma. 1045 17

The aim of the present study was to evaluate metabolic, coagulation and fibrinolytic parameters in 45 patients [31 men, 14 women, aged 56.5 +/- 3.5 years (mean +/- SD)] who had suffered myocardial infarction more than 6 months earlier, with or without carotid atherosclerotic lesions. After the extracranial carotid arteries had been evaluated using a B-mode Duplex scanning system, patients were subdivided into two groups: group 1 (n = 20) with carotid plaques or measurable intima-media thickness; and group 2 (n = 25) without carotid plaques or measurable intima-media thickness. Twenty-two age- and sex-matched subjects were recruited as controls (group 3). Groups 1 and 2 displayed significantly higher levels of total cholesterol, apolipoprotein B, human autoantibodies against oxidised low-density lipoprotein and the c fraction of the third component system, and significantly lower levels of high-density lipoprotein cholesterol and apolipoprotein A1 than group 3. However, serum levels of triglyceride and lipoprotein (a) were significantly higher in group 1 than in the control group. Moreover, groups 1 and 2 displayed significantly higher levels of factor VII, fibrinogen, fragment 1+2, thrombin-antithrombin complex and plasminogen activator inhibitor after venous occlusion, and significantly lower levels of tissue-type plasminogen activator after venous occlusion than group 3. Significantly higher levels of tissue-type plasminogen activator and plasminogen activator inhibitor before venous occlusion were observed in groups 1 and 2 and significantly lower levels of antithrombin III, protein C and protein S were observed in group 1 compared with the controls. Patients were also analysed according to levels of lipoprotein (a). The lowest levels of tissue-type plasminogen activator after venous occlusion and the highest levels fragment 1 + 2, the c fraction of the third component system, and plasminogen activator inhibitor after venous occlusion were observed in patients with the highest levels of lipoprotein (a). Our data demonstrate an activation of coagulation and deficient fibrinolysis in survivors of myocardial infarction, particularly in those with associated carotid atherosclerotic lesions. We speculate that this thrombophilic state may play a key role in the pathogenesis of atherosclerotic vascular disease and thromboembolic complications.
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PMID:Elevated levels of lipoprotein (a) in patients suffering from myocardial infarction with carotid atherosclerotic lesions. 1049 14

The aim of this study was to design a simple laboratory method that can screen the overall haemostatic potential in plasma (OHPP) when a hyper- or hypocoagulable state is present. A fibrin time curve was made via spectrophotometric registration of fibrin generation and lysis in plasma, to which exogenous thrombin and tissue type plasminogen activator was added. The area under the curve, calculated by the sum of absorbance (ABS-sum), varied in correlation to the concentrations of platelets or purified pro-/anticoagulants: tissue factor, von Willebrand factor, fibrinogen, antithrombin, plasminogen, or plasminogen activator inhibitor type 1. The ABS-sums also changed in positive relation to the haemostatic function investigated in 16 menopausal women and 14 young healthy nonpregnant women (controls). The findings imply that the ABS-sums not only offer a general information about fibrin generation and lysis in vitro, but also reflect the OHPP (i.e., final combined effects of platelet activity, coagulation, and fibrinolysis in vivo). Preliminary results were satisfactory; the levels of OHPP, expressed as the ABS-sums, were higher in normal pregnant women than in the controls, and even higher in preeclamptic patients than in pregnant women with no complications, which corresponds to the different grades of hypercoagulability in the three groups. Moreover, the level of OHPP was considerably lower in an untreated infant with von Willebrand's disease type 3 and in factor VIII- or factor IX-deficient plasma samples.
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PMID:A laboratory method for determination of overall haemostatic potential in plasma. I. Method design and preliminary results. 1057 92

During and following significant surgical intervention, deep venous thrombosis prophylaxis by application of anticoagulants is routinely used. However, patients with malignant disorders are subject to an especially high risk of deep venous thrombosis progressing in severe cases to subsequent pulmonary embolism. The present study focuses on appraising modern markers of deep vein thrombosis in 34 patients undergoing major maxillofacial surgery, with some malignant disorders. No significant differences between the two patient groups were noted using the markers of the kallikrein-kinin-system. From the first postoperative day plasma levels of the coagulation indicator thrombin-antithrombin-III complexes were significantly higher in the group of tumour patients. Markers of fibrinolysis indicated corresponding results: on the first postoperative day tissue-plasminogen activator values rose to 18.9 +/- 3.2 micrograms/l in the group of malignant patients, but only to 7.4 +/- 1.1 micrograms/l (P < 0.05) in the control group. Also postoperative D-dimer concentrations in the malignancy group were significantly above those of the control group. In the present study it could be demonstrated that patients with malignant neoplasia undergoing major maxillofacial surgery are exposed postoperatively to a particularly high risk of developing thromboembolic complications. All in all, the status of anti-thrombotic therapy requires reappraisal with respect to the current treatment approach adopted in tumour patients.
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PMID:Evaluation of markers of deep vein thrombosis in patients undergoing surgery for maxillofacial malignancies. 1062 61

We have investigated hemostatic parameters including platelet activation in 56 pediatric patients with or without cyanosis undergoing cardiopulmonary bypass (CPB) and cardiac surgery to repair congenital defects. Patients were participants in a study assessing the effects of tranexamic acid on surgery-related blood loss. Parameters monitored included blood loss, prothrombin F1.2, thrombin-antithrombin complexes, t-PA, PAI-1, plasminogen, fibrin D-dimer, and plasma factor XIII. Additionally, flow cytometry monitored platelet degranulation (P-selectin or CD63), as well as surface-bound fibrinogen, von Willebrand factor and factor XIIIa. Cyanotic patients had evidence of supranormal coagulation activation as both fibrin D-dimer and PAI-1 levels were elevated prior to surgery. While the extent of expression of P-selectin or CD63 was not informative, platelet-associated factor XIIIa was elevated in cyanotic patients at baseline. In both patient groups, CPB altered platelet activation state and coagulation status irrespective of the use of tranexamic acid.
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PMID:Hemostatic parameters and platelet activation marker expression in cyanotic and acyanotic pediatric patients undergoing cardiac surgery in the presence of tranexamic acid. 1066 55

We studied 67 healthy women who were randomly allocated to receive third generation gestodene (Gynera) or second generation levonorgestrel (Microgynon 30) combination of low-dose estrogen oral contraceptives (OCs) for their hemostatic effects over 2 years. Hemostatic changes were apparent within 3 months of OC use. Hematocrit (Hct) was not affected, but hemoglobin (Hb) concentration decreased by 18 months. Shortened prothrombin time (PT) and activated plasma thromboplastin time (APTT) were associated with elevated fibrinogen within the 12-month use of both OCs. Factor VII was reduced only in Micro 30 during the 18 months of use. Enhanced thrombin-antithrombin (TAT)-complex level was seen at 18 months of Gynera use. Prothrombin fragment1+2 (F1+2) rise was seen at 3 months with Micro 30. Reduced antithrombin III (ATIII) activity was seen at 18 months with Gynera and at 24 months with Micro 30. Increased protein C activity was seen at 3 months and reduced protein S occurred at 18 months of Gynera use. Tissue plasminogen activator (t-PA) activity was enhanced for 6 months in both OCs with raised D-dimer levels for 12 months with Gynera and 6 months with Micro 30. Decreased t-PA antigen was seen at 18 months and decreased urokinaselike plasminogen activator (u-PA) antigen occurred throughout the 24 months of both OCs use. Enhanced u-PA activity was only seen in Gynera users. Elevated plasminogen levels were apparent throughout both OCs use. PAI-1 levels were significantly decreased with Micro 30. With Gynera, the decreased PAI-1 activity was seen only at 18 months and PAI-1 antigen at 12 months. No change in platelets and von Willebrand factor (vWF) were seen in long-term OC use except that beta-thromboglobulin (beta-TG) showed decreased trends reaching statistical significance by 18 and 24 months of Micro 30 use and by 24 months of Gynera use. A further significant decrease in beta-TG, u-PA antigen, ATIII, and protein S levels were seen 3 months after pill stoppage compared with pretreatment levels. Activated protein C resistance (APCR) was negative in all subjects before and during OC use. The study indicated dynamic balance between coagulation and fibrinolysis with no endothelial activation. However, because some hemostatic markers showed wide fluctuations during OC use, a longer term study is warranted to investigate any adverse hemostatic changes that might enhance the risks of venous thromboembolism in Asian subjects known to be less prone to thrombosis.
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PMID:Effects on hemostasis after two-year use of low dose combined oral contraceptives with gestodene or levonorgestrel. 1072 85

The influence of age on training-induced changes in resting and stimulated hemostatic potential was studied in three age categories (Cat I-III; 20-30 yr, 35-45 yr, and 50-60 yr, respectively) of sedentary men before and after 12 wk of training. Coagulation, fibrinolytic activity, and activation markers (reflecting fibrin formation and degradation) were determined. Physical conditioning resulted in a more pronounced increase in von Willebrand factor (vWF) and factor VIII clotting activity (FVIII:c) in Cat I and II and a more pronounced shortening of the activated partial thromboplastin time in all categories at maximal exertion and during recovery. Enhanced increases in tissue-type plasminogen activator (t-PA) antigen and activity and single-chain (sc) urokinase-type plasminogen activator (u-PA) at maximal exercise and 5 min of recovery were observed in all age groups after training. The effects on FVIII:c, vWF, and scu-PA were most pronounced in the youngest age group (Cat I). Increases in the marker of thrombin generation were highest in Cat III; no effect was seen on thrombin-antithrombin complex, plasmin-antiplasmin complex, and D-dimer in any of the age groups. We concluded that training enhances both coagulation and fibrinolytic potential during strenuous exercise. The effect on FVIII/vWF and t-PA/u-PA is most pronounced in younger individuals, whereas thrombin formation is most pronounced in older individuals.
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PMID:Aging, physical conditioning, and exercise-induced changes in hemostatic factors and reaction products. 1079 12

Antiphospholipid antibodies are well recognized as associated with serious clinical complications such as arterial and venous thrombosis and recurrent spontaneous abortion. These complications are collectively called antiphospholipid syndrome(APS). The mechanisms responsible for the thrombosis are unclear. We reported three mechanisms. beta 2-glycoprotein I(beta 2GPI) inhibited activated protein C(APC) activity and, furthermore, APC activity decreased by the addition of monoclonal aCL and beta 2GPI. Monoclonal anticardiolipin antibodies(aCL) seemed to enhance the inhibition of APC procoagulant activity caused by beta 2GPI. Monoclonal aCL in the presence of beta 2GPI also increased the activity of plasminogen activator inhibitor(PAI)-1 in the mixture of tissue-plasminogen activator(t-PA) and PAI-1 by inhibiting the function of beta 2GPI, which increased the remaining t-PA activity in the mixture. The formation of thrombin-antithrombin complexes(TAT) in APS was impaired. The level of TAT in APS did not increase, however the level of prothrombin fragment 1 + 2 (F1 + 2) increased. Therefore, free thrombin present in patients' blood may contribute to thrombosis in APS. These reports indicate that thrombosis in APS may be caused by several thrombogenic factors that stimulate aCL.
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PMID:[Antiphospholipid antibodies and thrombosis: the putative mechanisms of hypercoagulable state in patients with anticardiolipin antibody]. 1081 Aug 73


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