[Assessment of anti-factor Xa activity for heparin and related products by chromogenic assays and thrombin generation tests].

Anticoagulant therapy is widely used for the prevention and treatment of thromboembolism. In addition to established agents such as warfarin, unfractionated heparin and low-molecular-weight heparins, a variety of new anticoagulant drugs has been introduced for clinical use, including direct thrombin inhibitors and factor Xa inhibitors. These new drugs can be given at fixed doses without the need for routine monitoring of the coagulation profile. However, an assays to evaluate anticoagulant strength would be valuable to prevent undesired hemorrhagic or thromboembolic events during treatment. In the present study, we examined the feasibility of several laboratory monitoring tests, including chromogenic-based anti-factor Xa assay and the thrombin generation test to determine the anticoagulant effect of low-molecular-weight heparins and fonda-parinux. Dose-dependent relationship between anti-factor Xa activity and the concentration of fondaparinux was observed by the chromogenic assays. In the thrombin generation test, the peak parameter seemed to be more informative than the endogenous thrombin potential, which corresponds to the total amount of thrombin activity, to assess the pharmacodynamic effects. In summary, our study suggested that both assays may be useful for quantitative determination of factor Xa activity. Further studies are necessary to develop and establish simpler methods that can be used in routine laboratory testing to monitor treatment with the newer anticoagulant drugs.

[Condition setting for the measurement of blood coagulation factor XIII activity using a fully automated blood coagulation analyzer, COAGTRON-350].

The automated laboratory analyzer COAGTRON-350 (Trinity Biotech) is used for routine and specific coagulation testing for the detection of fibrin formation utilizing either mechanical principles (ball method) or photo-optical principles, chromogenic kinetic enzyme analysis, and immune-turbidimetric detection systems in one benchtop unit. In this study, we demonstrated and established a parameter for the measurement of factor XIII (FXIII) activity using Berichrom FXIII reagent and the COAGTRON-350 analyzer. The usual protocol used for this reagent, based on the handling method, was slightly modified for this device. The analysis showed that fundamental study for the measurement of FXIII activity under our condition setting was favorable in terms of reproducibility, linearity, and correlation with another assays. Since FXIII is the key enzyme that plays important roles in hemostasis by stabilizing fibrin formation, the measurement of FXIII is essential for the diagnosis of bleeding disorders. Therefore, FXIII activity assessment as well as a routine coagulation testing can be conducted simultaneously with one instrument, which is useful in coagulopathy assessment.

[Questionnaire survey of the POCT device antsense ROSE for blood glucose analysis on healthcare professionals--evaluation focused on preventive measures against cross-infections].

Considering the possibility of being used for any patients, such a risk-managed medical device is necessary in the perspective of the prevention of hospital infections. Antsense ROSE, a newly developed POCT (Point of Care Testing) diagnostic device for blood glucose analysis, is designed for safety in hospital use. Use of a disposable chip filter for blood sampling prevents cross-infection through device. As to infection control, we carried out a questionnaire survey of healthcare professionals specialists in diabetes to evaluate the feasibility of this device in clinical practice. Despite the infection control system of this device, the survey participants pointed out only a little improvement in infection risk compared with conventional methods. Some were concerned about the cross-infection because blood sampling itself increases the risk of infection, and because it is difficult for examiners to prevent infections completely due to handling blood samples. Systems ensuring safety, such as a fail-safe, are essential for in-hospital use to prevent hospital infections due to the possibility of using a device for several patients, and to ensure the security even for wrong operations. Further investigations, developments and educational campaign will be required for the use of risk managed devices against in-hospital infections.

Hyperfibrinogenemia is associated with lymphatic as well as hematogenous metastasis and worse clinical outcome in T2 gastric cancer.

BACKGROUND: Abnormal hemostasis in cancer patients has previously been described, however the correlation between the plasma fibrinogen level and cancer metastasis and prognosis has not been reported in a large-scale clinical study. METHODS: Preoperative plasma fibrinogen levels were retrospectively examined in 405 patients who underwent surgery for advanced gastric cancer. The association of fibrinogen levels with clinical/pathological findings and clinical outcome was evaluated. RESULTS: There was a positive correlation between plasma fibrinogen levels and the depth of invasion (p < 0.05). Hyperfibrinogenemia (>310 mg/dl) was independently associated with lymph node (Odds Ratio; 2.342, P = 0.0032) and liver (Odds Ratio; 2.933, P = 0.0147) metastasis, not with peritoneal metastasis in this series. Patients with hyperfibrinogenemia showed worse clinical outcome in T2 gastric cancer, however, there was no correlation of plasma fibrinogen level with prognosis in T3/T4 gastric cancer. CONCLUSION: Our results might support the idea that hyperfibrinogenemia can augment lymphatic and hematogeneous metastasis of advanced gastric cancer, which is major determinant of the prognosis in T2 gastric cancer. Therefore, in the situation without peritoneal involvement, hyperfibrinogenemia is a useful biomarker to predict the possible metastasis and worse clinical outcome in T2 gastric cancer.