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Background: Heparin-Induced Thrombocytopenia (HIT) represents a serious complication of heparin treatment. IgG antibodies binding Platelet Factor 4 (PF4) and heparin trigger the clinical manifestations of HIT. A 4T score is used to stratify the selection of patients suitable for examination. However, the selection of suitable patients remains at the discretion of the clinician, who is confronted with determining the cause of thrombocytopenia. The inclusion of the evaluation of the Immature platelet fraction result seems to be a suitable complement to the stratification of patients because we do not climb elevated IPF values when consuming platelets due to their immunization. Materials and Methods: In a group of 432 thrombocytopenic samples IPF was detected and analyzed in 45 patients with suspected HIT, a 4T score was determined; IPF and HIT functional tests were examined. IPF was determined by oxazine fluorescent dyeing structures of nucleic acid-containing platelets and fluorescence detection on a Sysmex XN 1000 analyser. To determine HIT, impedance aggregometry using the Multiplate® analyser (MEA) as heparin-induced aggregation techniques. The MEA method uses sensitization of donor platelets with patient plasma in the presence of heparin at a concentration of 0.5IU/mL. Results: From the results of the test, it is evident that 10 patients from our group of 45 examined showed positivity of HIT, which is a significant number due to the proven occurrence of HIT in patients treated with LMWH and showing thrombocytopenia. If we evaluate these 10 patients in terms of IPF value, it is evident that 6 of them have an increased value of IPF >10%, which is a 33% positive predictive value and 4 have IPF >30%, when the positive predictive value is even 100%. Conclusions: Diagnosis of HIT remains a complicated clinical laboratory issue. However, new diagnostic options provide considerable potential for solving this problem. The implementation of IPF assays helps us in the diagnosis of HIT on two levels. On the one hand, it provides us with information on platelet consumption in hospitalized patients and thus draws our attention to HIT as one of the options for congestive thrombocytopenia, unless, of course, disseminated intravascular coagulation or thrombotic microangiopathy. Secondly, its implementation will increase the predictive value of the 4T score in patients at medium risk, which is, however, the vast majority indicated for HIT examination.

Anti-cardiolipin antibodies (ACL) and anti-β-2-glycoprotein I antibodies (anti-2GPI) represent two out of three laboratory criteria for detection of antiphospholipid syndrome (APS). The domain I (DI) in anti-β-2-glycoprotein I is a new target for better identification of antibodies and may be associated with thrombotic risk in antiphospholipid syndrome. Anti-β2GPI antibodies specifically reacting with DI have a particular clinical importance being more commonly detected among patients with APS and other autoimmune diseases. This observation implies that compared with antibodies targeting the whole molecule, anti-DI antibodies have higher specificity for APS. Routine testing for anti- DI antibodies in clinical practice can be used for an easy differentiation of subjects carrying clinically meaningful anti- β2GPI antibodies from those individuals with a benign autoantibody profile. The aim of our study was to determine the significance of the domain I in the anti-β-2-glycoprotein I as a new biomarker for determining thrombotic risk in antiphospholipid syndrome. We investigate the DI anti-β2GPI on a group of 74 patients with antiphospholipid syndrome diagnosis. All patients have positive antibodies in at least one class ACL and anti-β2GPI antibodies. We detect DI anti-β2GPI positivity in 21 samples in our group. The thrombotic complications had been observed in 21 from 74 patients. The incidence of thrombotic complications in the total group was established as 28.4%, in comparison to the group DI anti-β2GPI positive with the incidence of thrombotic complications 57%. Performing of assay improved a positive predictive value from 25% pre-test to 68% for patients with positive test. The new chemiluminescent method for detection of DI anti-β2GPI shows a better compliance with clinical outcome than the actual diagnostic scheme.

The Global Stratotype Section and Point (GSSP) of the Silurian/Devonian boundary, Lower Devonian Series and Lochkovian Stage was formally placed in 1977 at Klonk, in the Czech Republic, at the first appearance of the graptolite Uncinatograptus uniformis uniformis (Přibyl). However, since then, correlation of this limit has been often hampered in carbonate facies where graptolites are uncommon or totally absent. A large calcareous deposition occurred at the Silurian/Devonian boundary along the northern and peri-Gondwana margin, thus representing an ideal location to select and test a possible additional biostratigraphic marker of the limit among conodonts. The first appearance of Caudicriodus hesperius almost simultaneously at the base of the Devonian in Bohemia, the Carnic Alps, Sardinia, Morocco and elsewhere indicates that this taxon is the conodont that best approximates the beginning of the Period. The first or last appearance of other species (e.g., Ozarkodina confluens, Zieglerodina klonkensis, Z. remscheidensis and Caudicriodus woschmidti) may help to recognise the boundary as well.