Effects of a multi-strain Bacillus spp. direct-fed microbial and a protease enzyme on growth performance, nutrient digestibility, blood characteristics, fecal microbiota, and noxious gas emissions of grower pigs fed corn-soybean-meal-based diets-A meta-analysis

Three studies involving 352 grower pigs were conducted to determine the effects of dietary supplementation with multistrain spp. direct-fed microbial (DFM) and protease, alone or in combination, on growth performance, nutrient digestibility, blood characteristics, fecal microbiota, and noxious gas emissions, and to use a meta-analysis to increase the reliability of the findings. Treatments ( = 4) were set up as a 2 × 2 factorial design with 2 levels of protease (0 and 5.000/6.000 units/kilogram of feed [U/KG]) and 2 levels of DFM (0 and 1.5 × 10 colony forming units/gram of feed [CFU/G]), plus a protease + DFM combination. Pigs were housed in groups of 3 or 4/pen with 8 replicate pens/treatment. Experimental diets were fed for 42 d and feed intake and BW were measured weekly. Fecal samples were collected at d 42 and analyzed to determine apparent total tract digestibility (ATTD). Fecal counts of and coliforms, and noxious gas emissions were measured. Blood samples were taken by anterior vena cava puncture to measure blood urea nitrogen (BUN) and creatinine. Data from the 3 studies were pooled and analyzed as a 2 × 2 factorial using the Fit Model platform of JMP 11 (SAS Inst. Inc., Cary, NC). Means separation was determined using Tukey's honest significant difference test. The main effect of protease and DFM increased: BW at 42 d, overall ADG, and overall G:F compared to the control ( < 0.04). There were no interactions between protease and DFM ( > 0.05); however, the protease + DFM combination was the only treatment to improve ADG and G:F in all phases compared to the control. The main effect of protease increased ATTD of DM, nitrogen (N), and ADF ( < 0.04). The main effect of DFM increased ATTD of DM, N, GE, DE, ADF, and fat ( < 0.02). There was a trend for an interaction between protease and DFM for ATTD of GE and DE ( < 0.08) because the protease + DFM combination increased energy digestibility more than the additive effects of the protease and DFM alone. The main effects of protease and DFM decreased fecal ammonia emissions ( < 0.01), but the protease + DFM combination was the only treatment to decrease ammonia emissions compared to the control. In conclusion, the main effects of protease and DFM improved growth performance and nutrient digestibility compared to the control, but there was a greater additive effect of the protease + DFM combination on energy and N digestibility.

Venous thromboembolism in hospitalized patients receiving chemotherapy for malignancies at Japanese community hospital: prospective observational study

BACKGROUND

Although Asian population was recognized to have a lower risk of venous thromboembolism (VTE), its increasing prevalence and incidence remain unclear in patients with malignancies. We attempted to predict VTE development using activation markers of coagulation and fibrinolysis.

METHODS

We enrolled patients with malignancy admitted to Tonan Hospital between April and December 2014 to receive a new-for-them chemotherapy regimen. All patients were examined for VTE by computed tomography and whole-leg compression ultrasonography before chemotherapy and three months later. We also examined plasma levels of thrombin-antithrombin complex (TAT) and plasmin α2-plasmin inhibitor complex (PIC) before chemotherapy. The cut off values of TAT and PIC were set at 2.1 ng/mL and 1.8 μg/mL, respectively.

RESULTS

Of 97 patients, the majority (67%) had distant metastases. The most common malignancies were colorectal (26%), breast (23%), and stomach (19%) cancer. VTE was detected in 29 patients (31%); all were asymptomatic. VTE was newly developed in 12 patients in the three-month observation period, which means the incidence was 49 per 1000 person-years. Non-increased PIC with increased TAT was the only significant risk factor for both VTE prevalence and incidence in multivariate analysis, and the odds ratios were 3.0 (95% confidence interval, 1.1-8.2; P = 0.034) and 9.4 (95% confidence interval, 1.7-51.9; P = 0.011), respectively.

CONCLUSIONS

The prevalence and incidence of VTE were high in hospitalized Japanese patients receiving chemotherapy for malignancies. Non-increased PIC with increased levels of TAT may be an independent risk factor for VTE development.

Phase 1 dose-escalating study to evaluate the safety, pharmacokinetics, and pharmacodynamics of a recombinant factor Xa variant (FXaI16L )

Essentials FXaI16L is a recombinant zymogen-like variant of activated coagulation factor X (FXa). A phase 1 dose escalation clinical trial of FXaI16L was conducted in healthy adults. FXaI16L was safe and tolerated at doses up to 5 μg/kg; no dose-limiting toxicity was observed. Data support further development of FXaI16L for patients with acute hemorrhagic conditions.

SUMMARY

Background FXaI16L (PF-05230907) is a zymogen-like variant of activated factor X (FXa). It shows enhanced resistance to inactivation by endogenous inhibitors as compared with wild-type FXa, and restores hemostatic activity in non-clinical models of various bleeding conditions. Objectives To evaluate the safety, pharmacokinetics and pharmacodynamics of FXaI16L by performing a phase 1, first-in-human, dose-escalation clinical trial in healthy adult volunteers. Methods Participants were assigned to one of six ascending single-dose cohorts (0.1, 0.3, 1, 2, 3 or 5 μg kg-1 ), each planned to comprise six volunteers treated with FXaI16L and two treated with placebo. Assessments included safety monitoring, pharmacokinetic and pharmacodynamic (PD) analyses, and immunogenicity testing. Results The trial enrolled 49 male volunteers. Administration of a single intravenous bolus dose of FXaI16L was safe and tolerated at all dose levels tested, with no dose-limiting toxicity or serious adverse events. FXaI16L plasma levels appeared to increase dose-proportionally, with a half-life of ~ 4 min. Treatment-related PD changes were observed for activated partial thromboplastin time, thrombin generation assay, thrombin-antithrombin complexes, prothrombin fragment 1 + 2, and D-dimer. One volunteer had a weak and transient non-neutralizing antidrug antibody response, which did not cross-react with native FX or native FXa. Conclusions FXaI16L was safe and tolerated, and showed a pharmacologic effect in healthy adults when administered at doses up to 5 μg kg-1 . The safety profile, pharmacokinetics and pharmacodynamics observed in this clinical trial support the further development of FXaI16L for hemostatic treatment in individuals with acute hemorrhagic conditions.

[Effect of ulinastatin on serum levels of tumor necrosis factor-α, P-selectin, and thrombin-antithrombin complex in young rats with sepsis]

OBJECTIVE

To investigate the effect of ulinastatin (UTI) for early drug intervention on the serum levels of tumor necrosis factor-α (TNF-α), P-selectin, and thrombin-antithrombin complex (TAT) in young rats with sepsis.

METHODS

A total of 120 male rats aged 4 weeks were randomly divided into normal control group, sham-operation group, sepsis group, low-dose UTI group (50 000 U/kg), and high-dose UTI group (200 000 U/kg), with 24 rats in each group. Modified cecal ligation and puncture was performed to establish a rat model of sepsis, and the rats in the low- and high-dose UTI groups were given caudal vein injection of UTI after model establishment. ELISA was used to measure the serum levels of TNF-α, P-selectin, and TAT at 6, 12, and 24 hours after model establishment.

RESULTS

The sepsis group had significant increases in the serum levels of TNF-α, P-selectin, and TAT at 6 hours, and the serum levels of TNF-α and TAT continued to increase by 24 hours (P<0.05); P-selectin reached the peak at 12 hours and decreased slightly at 24 hours (P<0.05). The UTI groups had similar change patterns in the levels of P-selectin and TAT as the sepsis group. The UTI groups had significant increases in the level of TNF-α at 6 hours, but gradually decreased over time. The changes in serum levels of TNF-α, P-selectin, and TAT in the UTI groups were significantly smaller than in the sepsis group (P<0.05). The high-dose UTI group had significantly smaller changes in serum levels of TNF-α, P-selectin, and TAT than the low-dose UTI group (P<0.05).

CONCLUSIONS

Early intervention with UTI can significantly improve coagulation function and inhibit the production of TNF-α, P-selectin, and TAT in young rats with sepsis. High-dose UTI has a significantly greater effect than low-dose UTI.

[Effect of ulinastatin on serum levels of tumor necrosis factor-α, P-selectin, and thrombin-antithrombin complex in young rats with sepsis]

OBJECTIVE

To investigate the effect of ulinastatin (UTI) for early drug intervention on the serum levels of tumor necrosis factor-α (TNF-α), P-selectin, and thrombin-antithrombin complex (TAT) in young rats with sepsis.

METHODS

A total of 120 male rats aged 4 weeks were randomly divided into normal control group, sham-operation group, sepsis group, low-dose UTI group (50 000 U/kg), and high-dose UTI group (200 000 U/kg), with 24 rats in each group. Modified cecal ligation and puncture was performed to establish a rat model of sepsis, and the rats in the low- and high-dose UTI groups were given caudal vein injection of UTI after model establishment. ELISA was used to measure the serum levels of TNF-α, P-selectin, and TAT at 6, 12, and 24 hours after model establishment.

RESULTS

The sepsis group had significant increases in the serum levels of TNF-α, P-selectin, and TAT at 6 hours, and the serum levels of TNF-α and TAT continued to increase by 24 hours (P<0.05); P-selectin reached the peak at 12 hours and decreased slightly at 24 hours (P<0.05). The UTI groups had similar change patterns in the levels of P-selectin and TAT as the sepsis group. The UTI groups had significant increases in the level of TNF-α at 6 hours, but gradually decreased over time. The changes in serum levels of TNF-α, P-selectin, and TAT in the UTI groups were significantly smaller than in the sepsis group (P<0.05). The high-dose UTI group had significantly smaller changes in serum levels of TNF-α, P-selectin, and TAT than the low-dose UTI group (P<0.05).

CONCLUSIONS

Early intervention with UTI can significantly improve coagulation function and inhibit the production of TNF-α, P-selectin, and TAT in young rats with sepsis. High-dose UTI has a significantly greater effect than low-dose UTI.

Platelet aggregability in patients with interstitial pneumonias

BACKGROUND

Recent epidemiological studies have shown that patients with interstitial pneumonia have an increased risk of cardiovascular events. Although the presence of a coagulation/fibrinolysis abnormality in idiopathic pulmonary fibrosis (IPF) has been reported, platelet aggregability has not been evaluated in interstitial pneumonias. This study aimed to investigate platelet aggregability in patients with interstitial pneumonias.

METHODS

This observational cohort study included 59 patients with interstitial pneumonias [19 with IPF, 23 with other idiopathic interstitial pneumonias (IIPs), and 17 with connective tissue disease-associated interstitial pneumonias (CTD-IPs)] and 23 healthy control subjects. ADP- and collagen-induced platelet aggregability was measured together with coagulation/fibrinolysis markers. Whole blood (WB) and platelet rich plasma platelet aggregation were measured using the screen filtration pressure and optical aggregometer techniques, respectively. The platelet aggregation threshold index (PATI) was calculated; a lower PATI indicated enhanced platelet aggregability.

RESULTS

ADP-induced WB-PATI was significantly decreased in CTD-IPs [log WB-PATI median 0.31 (inter-quartile range, 0.07-0.34) μM, n = 17] compared with that in controls [0.35 (0.32-0.45) μM, n = 23] (p < 0.05). However, there was no significant difference in platelet aggregability between the other patient groups and controls. In contrast, d-dimer, thrombin-antithrombin complex, and von Willebrand factor levels were significantly higher in all patient groups compared with those in controls (p < 0.001). Platelet aggregability was not associated with either disease severity or survival.

CONCLUSIONS

Serum coagulation and fibrinolysis markers significantly increased in IIPs and CTD-IPs. In contrast, platelet aggregability was only weakly enhanced in CTDs, but not in IIPs.

Demonstration and Operative Influence of Low Prime Volume Closed Pump

Various improvements have been made in cardiopulmonary bypass (CPB) in the past few decades. We designed a new type of CPB to reduce the secretion of systemic inflammatory markers. We used a low prime volume pump (LPVP), completely closed CPB circuit and examined coagulant factors and inflammatory cytokines. In this study, we demonstrate the efficacy of LPVP using molecular biological data. Fourteen patients were randomized prospectively into two groups: Group L patients underwent LPVP ( n = 8) and Group N patients underwent normal prime volume CPB ( n = 6). We measured thrombin-antithrombin III complex (TAT), complement factor (C3a), and interleukin (IL)-10 levels at four time points. TAT (66.1 ± 15.1 ng·mL−1), C3a (1895 ± 282 ng·mL−1) and IL-10 (486 ± 114 pg·mL−1) levels in Group N were significantly higher than in Group L (TAT, 19.5 ± 4.4 ng·mL−1; IL-10, 105 ± 24.6 pg·mL−1; C3a, 1349 ± 369 ng·mL−1) immediately following CPB. LPVP demonstrated a lower systemic inflammatory response compared to normal prime volume CPB, as assessed using a molecular biological approach.

The effects of increasing dietary levels of amino acid-supplemented soy protein concentrate and constant dietary supplementation of phosphorus on growth, composition and immune responses of juvenile Atlantic salmon (Salmo salar L.)

Diets with 50 (SPC50), 65 (SPC65) and 80 % (SPC80) substitution of prime fish meal (FM) with soy protein concentrate (SPC) were evaluated against a commercial type control feed with 35 % FM replacement with SPC. Increases in dietary SPC were combined with appropriate increases in methionine, lysine and threonine supplementation, whereas added phosphorus was constant among treatments. Diets were administered to quadruplicate groups of 29 g juvenile Atlantic salmon were exposed to constant light, for 97 days. On Day 63 salmon were subjected to vaccination. Significant weight reductions in SPC65 and SPC80 compared with SPC35 salmon were observed by Day 97. Linear reductions in body cross-sectional ash, Ca/P ratios, and Ca, P, Mn and Zn were observed at Days 63 (prior vaccination) and 97 (34 days post-vaccination), while Mg presented a decrease at Day 63, in salmon fed increasing dietary SPC. Significant reductions in Zn, Ca, P and Ca/P ratios persisted in SPC65 and SPC80 compared with SPC35 salmon at Day 97. Significant haematocrit reductions in SPC50, SPC65 and SPC80 salmon were observed at Days 63, 70 and 97. Enhanced plasma haemolytic activity, increased total IgM, and a rise in thrombocytes were demonstrated in SPC50 and SPC65 salmon on Day 97, while increased lysozyme activity was demonstrated for these groups on Days 63, 70 and 97. Leucocyte and lymphocyte counts revealed enhanced immunostimulation in salmon fed with increasing dietary SPC at Day 97. High SPC inclusion diets did not compromise the immune responses of salmon, while SPC50 diet also supported good growth without compromising elemental concentrations.

Microparticle-Induced Coagulation Relates to Coronary Artery Atherosclerosis in Severe Aortic Valve Stenosis

Background

Circulating microparticles (MPs) derived from endothelial cells and blood cells bear procoagulant activity and promote thrombin generation. Thrombin exerts proinflammatory effects mediating the progression of atherosclerosis. Aortic valve stenosis may represent an atherosclerosis-like process involving both the aortic valve and the vascular system. The aim of this study was to investigate whether MP-induced thrombin generation is related to coronary atherosclerosis and aortic valve calcification.

Methods

In a cross-sectional study of 55 patients with severe aortic valve stenosis, we assessed the coronary calcification score (CAC) as indicator of total coronary atherosclerosis burden, and aortic valve calcification (AVC) by computed tomography. Thrombin-antithrombin complex (TATc) levels were measured as a marker for thrombin formation. Circulating MPs were characterized by flow cytometry according to the expression of established surface antigens and by measuring MP-induced thrombin generation.

Results

Patients with CAC score below the median were classified as patients with low CAC, patients with CAC Score above the median as high CAC. In patients with high CAC compared to patients with low CAC we detected higher levels of TATc, platelet-derived MPs (PMPs), endothelial-derived MPs (EMPs) and MP-induced thrombin generation. Increased level of PMPs and MP-induced thrombin generation were independent predictors for the severity of CAC. In contrast, AVC Score did not differ between patients with high and low CAC and did neither correlate with MPs levels nor with MP-induced thrombin generation.

Conclusion

In patients with severe aortic valve stenosis MP-induced thrombin generation was independently associated with the severity of CAC but not AVC indicating different pathomechanisms involved in coronary artery and aortic valve calcification.

Neutrophil activation and nucleosomes as markers of systemic inflammation in paroxysmal nocturnal hemoglobinuria: effects of eculizumab

BACKGROUND

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement-mediated hemolysis and a high risk of life-threatening venous and arterial thrombosis. Uncontrolled complement activation and the release of cell-free heme may result in systemic inflammation, neutrophil activation, and the release of procoagulant neutrophilic proteases. Eculizumab, an antibody to complement factor C5, inhibits hemolysis and reduces thrombotic risk.

OBJECTIVES

To study neutrophil activation and nucleosome levels in relation to thrombosis in PNH patients before and during treatment with eculizumab.

PATIENTS/METHODS

In 51 untreated PNH patients, including 20 patients before and after commencing eculizumab treatment, we have assessed neutrophil activation by measuring elastase-α1 -antitrypsin (EA) complexes and circulating nucleosomes, as established markers for systemic inflammation and cell death.

RESULTS

Nucleosomes (median; range; 95% confidence interval [CI]), but not EA complexes, were higher in PNH patients with a history of thrombosis (16; 7-264; 0.3-94 U mL(-1) , n = 12) than in those without (6; 6-35; 7-11 U mL(-1) , n = 39) or controls (8; 6-23; 7-12 U mL(-1) , n = 17). EA complexes, but not nucleosomes, decreased promptly and markedly upon eculizumab treatment. EA complexes (estimated marginal means; 95% CI) remained low at ≥ 12 weeks (50; 34-67) compared with baseline (12; -6 to 29).

CONCLUSIONS

The increased nucleosome levels in PNH patients with a history of thrombosis suggest systemic inflammation and/or cell death. Neutrophil activation markers did not differ between patients with and without a history of thrombosis and healthy controls. Interestingly, basal neutrophil activation in PNH patients significantly decreases on treatment with eculizumab, indicating that neutrophil activation is C5a driven.

[Thrombocytopenia induced by lipopolysaccharide may be not related to coagulation and inflammatory response]

OBJECTIVE

To explore the relationship between thrombocytopenia (TCP) induced by lipopolysaccharide (LPS) and coagulation or inflammatory response in mouse.

METHODS

Forty-eight C57BL/6 mice were divided into control group, low-dose, and high-dose LPS treatment groups by random number table method, and each group was subdivided into 4-hour and 24-hour subgroups randomly, with 8 mice in each subgroup. 0.5 mg/kg or 50 mg/kg LPS was injected intraperitoneally in low-dose or high-does group respectively, and equal amount of normal saline was injected in control group. Blood was collected from endocanthal vein at the specified time point, platelet count (PLT) was counted, and the levels of thrombin antithrombin complex (TAT), D-dimer, fibrinogen degradation product (FDP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined by enzyme linked immunosorbent assay (ELISA).

RESULTS

Compared with control group, PLT ( x 10(9)/L) at 4 hours and 24 hours in low-dose and high-dose LPS groups was significantly decreased (4 hours: 660.65 ± 180.48, 568.55 ± 117.99 vs. 1 199.13 ± 110.54; 24 hours: 505.63 ± 218.92, 256.33 ± 72.86 vs. 1 229.13 ± 1 189.37, all P < 0.05), and the changes were more obvious in high-dose LPS group compared with those of the low-dose LPS group (all P < 0.05). Factorial analysis showed that the changes in PLT were related with LPS dosage and time (F1 = 135.660, P = 0.000; F2 = 12.120, P2 = 0.001). It was also found that there was an interactive effect of the dose of LPS and time on PLT (F = 5.580, P = 0.007). Compared with control group, TAT, TNF-α, and IL-6 at 4 hours and 24 hours in low-dose and high-dose LPS groups were significantly decreased [TAT (ng/L) at 4 hours: 1.10 ± 0.59, 0.22 ± 0.13 vs. 3.47 ± 1.73; 24 hours: 1.18 ± 0.68, 0.39 ± 0.29 vs. 3.19 ± 1.27; TNF-α (nmol/L) at 4 hours: 87.35 ± 12.29, 93.70 ± 5.25 vs. 101.59 ± 10.96, 24 hours: 81.94 ± 8.26, 93.23 ± 4.71 vs. 102.84 ± 10.56; IL-6 (ng/L) at 4 hours: 81.78 ± 7.82, 78.59 ± 9.06 vs. 110.88 ± 9.66, 24 hours: 76.03 ± 9.85, 71.34 ± 3.69 vs. 110.88 ± 10.35, all P < 0.05]. TAT at 4 hours and 24 hours in high-dose LPS group was further decreased, and TNF-α at 24 hours was increased as compared with those of low-dose LPS group (all P < 0.05). TAT, TNF-α and IL-6 were influenced only by different dosage of LPS (TAT: F = 42.350, P = 0.000; TNF-α: F = 14.8 10, P = 0.000; IL-6: F = 81.910, P = 0.000), not time (TAT: F = 0.002, P = 0.967; TNF-α: F = 0.342, P = 0.562; IL-6: F = 2.973, P = 0.092). Changes in TAT was not found to be related with the dose of LPS and its time of action, or levels of TNF-α and IL-6 (TAT: F = 0.236, P = 0.791; TNF-α: F = 0.572, P = 0.569; IL-6: F = 0.774, P = 0.468). The dosage of LPS and time of admission showed no influence on D-dimer (F1 = 2.448, P = 0.099; F2 = 0.024; P2 = 0.877). The effect of different doses of LPS and time of administration showed no influence on FDP (F1 = 0.106, P = 0.900; F2 = 0.013, P2 = 0.908), and no interactive effects were found (D- dimer: F = 0.002, P = 0.998; FDP: F = 0.582, P = 0.563).

CONCLUSION

LPS can induce TCP in mouse, but this effect may not related to the activation of coagulation system and excessive inflammatory response.

Comparative studies of pharmacokinetics and anticoagulatory effect in rats after oral administration of Frankincense and its processed products

ETHNOPHARMACOLOGICAL RELEVANCE

Frankincense (FRA), Ruxiang, is the resin of Boswellia carterii Birdw and Boswellia bhaw-dajiana Birdw which has been used for centuries as formulas to improve the circulation and to relieve pain against carbuncles. Stir-fried Frankincense (SFF) and vinegar processed Frankincense (VPF) are two major processed Frankincense, and the processing procedures reportedly enhance the curative efficacy or reduce the side effects of FRA. This paper describes the comparisons in plasma pharmacokinetic behaviors of 11-keto-β-boswellic acid (KBA) and 3-acetyl-11-keto-β-boswellic acid (AKBA) in FRA and its processed products, and their effects on coagulation factors and blood clotting tetrachoric, using an acute cold blood-stasis animal model after oral administration of FRA, SFF, and VPF.

MATERIALS AND METHODS

For pharmacokinetic study, Sprague-Dawley (SD) rats were randomly divided into three groups, including group FRA, group SFF and group VPF. And the plasma samples were analyzed by HPLC. For study of anticoagulatory effect, SD rats were randomly divided into six groups, including control, acute cold blood-stasis model, Fu-fang-dan-shen tablet- (0.75g/kg), FRA-, SFF-, and VPF-treated (2.7g/kg) groups, respectively. The serum contents of thrombin-antithrombin complex (TAT), D-dimer (D-D), and prostacyclin (PGI2) of each group were measured by ELISA. The values of prothrombin time (PT), thrombin time (TT), activated partial thromboplastin time (APTT) and fibrinogen (FIB) were also assessed by hematology analyzer.

RESULTS

Significantly increased levels of Cmax, AUC, T1/2, and MRT were found in rats treated with the processed products. In addition, decreased levels of D-D and TAT and increased contents of PGI2 were observed in rats given FRA and its processed products, compared with that of the model group. Moreover, VPF improved anticoagulation more than SFF in the animals.

CONCLUSIONS

The observed improvement of anticoagulation by processed FRA may result from the increased absorption and bioavailability of triterpenoids.

Recombinant Factor VIIa Reduces Bleeding after Blunt Liver Injury in a Pig Model of Dilutional Coagulopathy under Severe Hypothermia

Background

Recombinant factor VIIa (rFVIIa) is registered for use in haemophilia with inhibitors and other rare bleeding disorders, but has also been used in various other clinical conditions to terminate life-threatening bleeding. Underlying conditions (e.g. coagulopathy) and dosing may affect treatment efficacy. The objective of the present study was to evaluate the impact of increasing doses of rFVIIa on blood loss and coagulation assays in haemodiluted and hypothermic pigs undergoing blunt liver injury.

Methods

A grade III blunt liver injury was induced in 28 pigs after 70% haemodilution and cooling to 32.6–33.4°C. Ten minutes after trauma, animals randomly received placebo or 90, 180 or 360 μg/kg rFVIIa. Global coagulation parameters, thromboelastometry (TEM) and plasma thrombin generation (TG) were determined at different time points during the observation period of 120 minutes.

Results

Total blood loss was significantly lower following 90 μg/kg rFVIIa (1206 [1138–1470] mL) relative to placebo (2677 [2337–3068] mL; p<0.05), with no increased effect with higher dose levels of rFVIIa. Following trauma and haemodilution, coagulation was impaired relative to baseline in both TEM and TG analysis. At 60 and 120 minutes after trauma, TEM variables improved in the rFVIIa-treated animals compared with the placebo group. Similarly, rFVIIa improved coagulation kinetics in TG. As was observed with blood loss, no significant effect between different rFVIIa dose levels was found in TEM or TG. Macro- and microscopic post-mortem examination did not reveal any signs of thromboembolic events.

Conclusion

Early administration of 90 μg/kg rFVIIa reduced blood loss in pigs undergoing blunt liver injury even after severe haemodilution and hypothermia, with no further effect of higher dose levels. Coagulation assays showed impaired coagulation in coagulopathic animals, with a dose-independent improvement in animals treated with rFVIIa.

Detection of Plasma Protease Activity Using Microsphere-Cytometry Assays with E. coli Derived Substrates: VWF Proteolysis by ADAMTS13

Protease levels in human blood are often prognostic indicators of inflammatory, thrombotic or oncogenic disorders. The measurement of such enzyme activities in substrate-based assays is complicated due to the low prevalence of these enzymes and steric hindrance of the substrates by the more abundant blood proteins. To address these limitations, we developed a molecular construct that is suitable for microsphere-cytometer based assays in the milieu of human blood plasma. In this proof of principle study, we demonstrate the utility of this substrate to measure metalloprotease ADAMTS13 activity. The substrate, expressed in E. coli as a fusion protein, contains the partial A2-domain of von Willebrand factor (VWF amino acids 1594-1670) that is mutated to include a single primary amine at the N-terminus and free cysteines at the C-terminus. N-terminus fluorescence conjugation was possible using NHS (N-hydroxysuccinimide) chemistry. Maleimide-PEG(Polyethylene glycol)n-biotin coupling at the C-terminus allowed biotinylation with variable PEG spacer lengths. Once bound to streptavidin-bearing microspheres, the substrate fluorescence signal decreased in proportion with ADAMTS13 concentration. Whereas recombinant ADAMTS13 activity could be quantified using substrates with all PEG repeat-lengths, only the construct with the longer 77 PEG-unit could quantify proteolysis in blood plasma. Using this longer substrate, plasma ADAMTS13 down to 5% of normal levels could be detected within 30 min. Such measurements could also be readily performed under conditions resembling hyperbilirubinemia. Enzyme catalytic activity was tuned by varying buffer calcium, with lower divalent ion concentrations enhancing cleavage. Overall, the study highlights the substrate design features important for the creation of efficient proteolysis assays in the setting of human plasma. In particular, it emphasizes the need to introduce PEG spacers in plasma-based experiments, a design attribute commonly ignored in immobilized peptide-substrate assays.

Identification of plasma protease derived metabolites of glucagon and their formation under typical laboratory sample handling conditions

RATIONALE

Glucagon modulates glucose production, and it is also a biomarker for several pathologies. It is known to be unstable in human plasma, and consequently stabilisers are often added to samples, although these are not particularly effective. Despite this, there have not been any studies to identify in vitro plasma protease derived metabolites; such a study is described here. Knowledge of metabolism should allow the development of more effective sample stabilisation strategies.

METHODS

Several novel metabolites resulting from the incubation of glucagon in human plasma were identified using high-resolution mass spectrometry with positive electrospray ionisation. Tandem mass spectrometric (MS/MS) scans were acquired for additional confirmation using a QTRAP. Separation was performed using reversed-phase ultra-high-performance liquid chromatography. The formation of these metabolites was investigated during a time-course experiment and under specific stress conditions representative of typical laboratory handling conditions. Clinical samples were also screened for metabolites.

RESULTS

Glucagon(3-29) and [pGlu](3) glucagon(3-29) were the major metabolites detected, both of which were also present in clinical samples. We also identified two oxidised forms of [pGlu](3) glucagon(3-29) as well as glucagon(19-29), or 'miniglucagon', along with the novel metabolites glucagon(20-29) and glucagon(21-29). The relative levels of these metabolites varied throughout the time-course experiment, and under the application of the different sample handling conditions. Aprotinin stabilisation of samples had negligible effect on metabolite formation.

CONCLUSIONS

Novel plasma protease metabolites of glucagon have been confirmed, and their formation characterised over a time-course experiment and under typical laboratory handling conditions. These metabolites could be monitored to assess the effectiveness of new sample stabilisation strategies, and further investigations into their formation could suggest specific enzyme inhibitors to use to increase sample stability. In addition the potential of the metabolites to affect immunochemistry-based assays as a result of cross-reactivity could be investigated.

[THROMBOGENIC RISK FACTORS IN PATIENTS WITH EXACERBATION OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE]

We studied activation of hemostatic reactions together with mechanisms of systemic inflammation and genetic factors responsible for thrombogenic risk in 65 patients suffering exacerbation of chronic obstructive pulmonary disease with 2 or 3 positive criteria proposed by N.Anthonisen at al. (1987). The levels of indicators of systemic inflammation, such as C-reactive protein and tumour necrosis factor-alpha, increased concurrently with those of homocysteine, endothelin-1, Willebrand factor plasminogen activator inhibitor type 1, and thrombin-antithrombin complex (marker of thrombinemia). The prevalence of pathological alleles ofprotein genes involved in the hemostasis system and folate cycle remained as in the control group. A relationship between plasma levels of thrombin-antithrombin complex and Willebrand factor and the activity of indicators of systemic inflammation was documented. Treatment of exacerbation resulted in the decrease in the levels of the thrombin- antithrombin complex, inhibitor of the extrinsic pathway of coagulation, and plasminogen activator inhibitor type 1. The treatment failed to normalize parameters of thrombinemia and blood fibrinolytic potential.

Tissue factor and other hemostatic parameters in patients with advanced peripheral artery disease after endovascular revascularization - search for hemostatic factors which indicate restenosis

BACKGROUND

In patients with peripheral artery disease (PAD) a hypercoagulable state and thromboembolic complications occur. Revascularization procedures increase this state, sometimes leading to restenosis. Restenosis following balloon angioplasty (PTA)and stent implantation is ≥ 50% of artery stenosis.

OBJECTIVES

To determine the concentration of tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombin-antithrombin (TAT) complexes, fibrinogen and D-dimers in the blood of patients with PAD after peripheral endovascular revascularization of the lower legs and in PAD patients with restenosis.

MATERIAL AND METHODS

The study included 150 patients with PAD, 90 men and 60 women, aged 44-88 (mean 65.5) years, after successful peripheral angioplasty (PTA) and/or with stenting. During the 6 months after the revascularization procedures, restenosis occurred in 27 patients. The reference group consisted of 53 healthy persons (44 men and 9 women, aged 20-56 years). Blood was drawn in the morning into 3.2% natrium citrate at a ratio of 9 : 1. The concentration of TF, TFPI, TAT complexes and D-dimers were measured in plasma with commercial tests using an enzyme immunoassay. Fibrinogen was determined with coagulometer.

RESULTS

In the plasma of patients with PAD after endovascular revascularization, the concentrations of TF, TAT complexes, fibrinogen and D-dimers were significantly higher compared to the reference group. During the six months of observation, 27 patients developed restenosis. The results of hemostatic factors in patients with restenosis were compared with the same patients before restenosis and the group of 123 PAD patients after endovascular revascularization. TF and fibrinogen levels in the 27 patients with restenosis were significantly higher than in the group of PAD patients before restenosis.

CONCLUSIONS

Statistically significantly higher levels of tissue factor (TF) and fibrinogen in PAD patients with new restenosis, compared to those without restenosis after endovascular revascularization, indicate they can participate in the formation of restenosis.

Coagulation-driven platelet activation reduces cholestatic liver injury and fibrosis in mice

BACKGROUND

The coagulation cascade has been shown to participate in chronic liver injury and fibrosis, but the contribution of various thrombin targets, such as protease activated receptors (PARs) and fibrin(ogen), has not been fully described. Emerging evidence suggests that in some experimental settings of chronic liver injury, platelets can promote liver repair and inhibit liver fibrosis. However, the precise mechanisms linking coagulation and platelet function to hepatic tissue changes following injury remain poorly defined.

OBJECTIVES

To determine the role of PAR-4, a key thrombin receptor on mouse platelets, and fibrin(ogen) engagement of the platelet αII b β3 integrin (αIIb β3 ) in a model of cholestatic liver injury and fibrosis.

METHODS

Biliary and hepatic injury was characterized following 4 week administration of the bile duct toxicant α-naphthylisothiocyanate (ANIT) (0.025%) in PAR-4-deficient mice, mice expressing a mutant form of fibrin(ogen) incapable of binding integrin αII b β3 (Fibγ(Δ5) ), and wild-type mice.

RESULTS

Elevated plasma thrombin-antithrombin and serotonin levels, hepatic fibrin deposition, and platelet accumulation in liver accompanied hepatocellular injury and fibrosis in ANIT-treated wild-type mice. PAR-4 deficiency reduced plasma serotonin levels, increased serum bile acid concentration, and exacerbated ANIT-induced hepatocellular injury and peribiliary fibrosis. Compared with PAR-4-deficient mice, ANIT-treated Fibγ(Δ5) mice displayed more widespread hepatocellular necrosis accompanied by marked inflammation, robust fibroblast activation, and extensive liver fibrosis.

CONCLUSIONS

Collectively, the results indicate that PAR-4 and fibrin-αII b β3 integrin engagement, pathways coupling coagulation to platelet activation, each exert hepatoprotective effects during chronic cholestasis.

Antithrombotic triple therapy and coagulation activation at the site of thrombus formation: a randomized trial in healthy subjects

BACKGROUND

Patients with acute coronary syndrome and concomitant atrial fibrillation may require antithrombotic triple therapy but clinical evidence of safety and efficacy is poor. We have therefore studied the combination of different antithrombotic medicines for coagulation activation in an in vivo model in the skin microvasculature.

METHODS AND RESULTS

Platelet activation (β-thromboglobulin [β-TG]) and thrombin generation (prothrombin fragment 1 + 2 [F1+2 ], thrombin-antithrombin complex [TAT]) were studied in an open-label, randomized, parallel group trial in 60 healthy male subjects (n = 20 per group) who received ticagrelor and acetylsalicylic acid (ASA) in combination with dabigatran (150 mg bid), rivaroxaban (20 mg od) or phenprocoumon (INR 2.0-3.0). Coagulation biomarkers in shed blood were assessed at 3 h after monotherapy with the medicines under study, at 3 h after triple therapy dosing and at steady state trough conditions. Single doses of ticagrelor, dabigatran or rivaroxaban caused comparable decreases in shed blood β-TG and were more pronounced than phenprocoumon at an INR of 2.0-3.0. In contrast, thrombin generation was more affected by rivaroxaban and phenprocoumon than by dabigatran. During triple therapy a similarly sustained inhibition of platelet activation and thrombin generation with a maximum decrease of β-TG, F1+2 and TAT at 3 h post-dosing was noted, which remained below pre-dose levels at trough steady state.

CONCLUSION

A triple therapy at steady state with ticagrelor plus ASA in combination with dabigatran or rivaroxaban is as effective as a combination with phenprocoumon for platelet activation and thrombin generation in vivo.

Expression of the PAR-1 protein on the surface of platelets in patients with chronic peripheral arterial insufficiency - preliminary report

BACKGROUND

The activation of pro-coagulation mechanisms associated with the vascular wall's immune and inflammatory responses wall to injury plays a crucial role in the mechanisms of the induction and progression of atherosclerosis.

OBJECTIVES

The aim of this study was to determine the role of protease activated receptors (PAR-1) expressed on the surface of blood platelets in the pathogenesis of chronic peripheral arterial obliterative disease (PAOD) in patients with obliterative atherosclerosis (n = 24) and diabetic macroangiopathy (n = 16), as well as in the controls (n = 12).

MATERIAL AND METHODS

In addition to the expression of PAR-1, serum/plasma concentrations of thrombin-antithrombin complex (TAT), the von Willebrand factor (vWF), the platelet-derived growth factor, monocyte chemotactic protein, the soluble form of the platelet endothelial cell adhesion molecule, thrombin activatable fibrinolysis inhibitor and interleukin 6 (IL-6) were determined.

RESULTS

Compared to the controls, PAOD patients were characterized by significantly higher levels of PAR-1 expression, vWF, TAT and IL-6. Individuals with diabetic macroangiopathy did not differ significantly from individuals with obliterative atherosclerosis in terms of PAR-1 expression. Upon activation with thrombin receptor antagonist peptide (TRAP), the levels of PAR-1 were comparable in all analyzed groups. In patients with diabetic macroangiopathy, a significant association was observed between the expression of PAR-1 on the surface of the platelet and the serum TAT concentration, as well as between TAT and serum IL-6 concentration.

CONCLUSIONS

Enhanced expression of PAR-1 on the thrombocyte surface in chronic PAOD patients occurs equally in cases of diabetic macroangiopathy and in individuals free from this endocrine pathology.

Intravascular hemolysis, vascular endothelial cell activation and thrombophilia in splenectomized patients with hemoglobin E/β-thalassemia disease

The relationship between asplenia and thrombophilia in β-thalassemia disease patients is not yet completely understood. One hundred and ten adult hemoglobin (Hb) E/β-thalassemia (E/β-Thal) disease outpatients, dichotomized according to the presence or absence of the spleen, were prospectively studied for evidence of intravascular hemolysis (IVH) and vascular endothelial cell (EC) activation. Biomarkers of IVH (serum cell-free Hb), EC [soluble E-selectin (sE-selectin) and soluble vascular cell adhesion molecule 1 (sVCAM-1)], platelet and EC [soluble P-selectin (sP-selectin)], inflammation [high-sensitivity C-reactive protein (hs-CRP)], and coagulation [thrombin-antithrombin complexes (TAT)] activation, as well as other selected blood tests were determined. The 61 splenectomized patients had a more severe hemolytic disease and higher levels of cell-free Hb and ferritin (p = 0.003), sE-selectin, sP-selectin, hs-CRP, and TAT (p < 0.05). However, serum levels of sVCAM-1 were not different between the two groups. The findings suggested IVH and EC activation. Together with chronic iron overload and chronic low-grade inflammation activation, the findings extend our understanding of the mechanism of thrombophilia in splenectomized E/β-Thal disease patients.

[About the biochemical criteria of heroin (narcotic) intoxication]

The article deals with the data of study of biochemical indicators and activity of particular proteolytic enzymes in blood serum of patients with heroin drug addiction. The results can be applied to detect the typical laboratory changes intrinsic to this kind of intoxication.

[Influence of pre-analytical storage conditions on four plasma coagulation molecular markers measured using a STACIA automatic coagulation analyzer]

We investigated the effects of specimen storage conditions on the analysis of the coagulation molecular markers, soluble fibrin (SF), thrombin-antithrombin complex (TAT), thrombomodulin (TM) and tissue plasminogen activator inhibitor-1 complex (total PAI-1: tPAI). Marker levels were measured using a STACIA automatic coagulation analyzer. Among these four markers in blood from healthy subjects, only tPAI increased gradually with time, and the differences were especially marked when blood samples were stored at room temperature. Patient blood samples were stored for 4 hours under three different conditions: whole blood storage on ice, storage on ice after centrifugation, and refrigerated storage after centrifugation. Analytical results were compared between the three sets of samples. There were no significant differences in TAT or TM after 4 hours' storage under the different conditions. However, SF was decreased in several samples. In 11 of 14 samples with >20 microg/ml SF, SF levels were reduced by >10 microg/ml when whole blood without centrifugation was stored on ice. tPAI levels increased slightly after storage for 4 hours under all three conditions. These results suggest that centrifugation followed by refrigeration is the optimal storage method for blood samples when all four markers are to be measured simultaneously in the same sample.