From unfractionated heparin to pentasaccharide: Paradigm of rigorous science growing in the understanding of the in vivo thrombin generation.

Following a chance discovery made by a medical student who was searching for a clot-promoting activity in tissue extracts, it took 15-20 years to attain the therapeutic use of standard unfractionated heparin (UFH), due to problems with the purification and extraction of the active material. Soon it was found that: 1) thrombin inactivation by UFH was associated with the formation of molecular complexes between antithrombin and the activated forms of factor X (FXa) and thrombin, 2) low-molecular-weight fractions of UFH lose their antithrombin activity while still interacting with FXa, 3) a pentasaccharide sequence of UHF increases FXa (but not thrombin) inactivation by antithrombin. Low-molecular-weight heparins (LMWHs) with little effect on thrombin and strongly active versus FXa were then developed. In patients, LMWHs (and the pentasaccharide sequence) came up as a useful class of drugs to prevent and treat thrombosis, their greatest advantage over UFH being the convenience of the once/twice daily subcutaneous injections at a fixed dose without any laboratory monitoring. In addition to providing major information on in vivo modulation of thrombin generation, the heparin saga served as a paradigm to support an alternative coagulation scheme that includes platelets and tissue factor as integral parts of the model. Forthcoming work with this scheme - also supported by studies in hemophilia and rare bleeding disorders - is expected to provide major hints for understanding why some patients benefit more than others from the small amount of thrombin they form and directions to tailor prevention and treatment of thromboembolic disorders.

Attempting to remedy sub-optimal medication adherence in haemophilia: The rationale for repeated ultrasound visualisations of the patient's joint status.

Haemophilia is marked by joint bleeding (haemarthrosis) leading to cartilage damage (arthropathy). Lifelong prophylaxis-initiated after the first bleeding episode-leads to a dramatic decrease in arthropathy in haemophilia patients. However, adherence to continuous intravenous administrations of factor VIII (FVIII) or FIX products is challenging, and patients potentially suffer from breakthrough bleedings while on prophylaxis. Newer FVIII/FIX products with enhanced convenience attributes and/or easier infusion procedures are intended to improve adherence. However, pharmacokinetic data should be harmonised with information from individual attitudes and treatment needs, to tailor intravenous dosing and scheduling in patients who receive extended half-life products. Nor is there sound evidence as to how subcutaneous non-FVIII/FIX replacement approaches (concizumab; emicizumab; fitusiran) or single intravenous injections of adeno-associated viral vectors (when employing gene therapy) will revolutionize adherence in haemophilia. In rheumatoid arthritis, repeated ultrasound examination of a patient's major joints is a valuable tool to educate patients and parents to understand the disease and provide an objective framework for clinicians to acknowledge patient's adherence. Joint ultrasound examination in haemophilia significantly correlates with cartilage damage, effusion, and synovial hypertrophy evaluated by magnetic resonance imaging. Furthermore, in patients with haemophilia undergoing prophylaxis with an extended half-life product for a ≈ 2.8 year period, a significant continued improvement in joint health is detected at the physical examination. This provides the rationale for studies on repeated ultrasound examinations of joint status to attempt to remedy sub-optimal medication adherence and help identify which approach is most suited on which occasion and for which patient.

Recombinant Activated Factor VII (Eptacog Alfa Activated, NovoSeven®) in Patients with Rare Congenital Bleeding Disorders. A Systematic Review on its Use in Surgical Procedures.

In the absence of definite guidelines in the area, we have carried a systemic review to provide a thorough overview concerning the efficacy and safety of recombinant activated factor VII (rFVIIa, NovoSeven®, Novo Nordisk A/S, Bagsværd, Denmark) in patients with Glanzmann's thrombasthenia (GT) and FVII deficiency, undergoing surgical procedures. PubMed, Web of Science, Scopus and EMBASE databases was employed for the search. Three multicenter registries were identified: the Glanzmann's Thrombasthenia Registry (GTR), the Seven Treatment Evaluation Registry (STER), and a German post-marketing surveillance registry (the WIRK study). In addition, data from 10 case-series and/or single-center experiences have been summarized. We have found that the following; perioperatively, the hemostatic effectiveness of rFVIIa was high in GT patients and in those with FVII deficiency undergoing both minor and major surgical procedures. Moreover, in all studies, rFVIIa was well tolerated. Thus, the current evidence shows an optimal perioperative safety/efficacy profile of rFVIIa in the setting of these rare bleeding disorders, and provides the rationale for further studies aimed at evaluating the optimal perioperative anti-hemorrhagic prophylaxis with rFVIIa in GT and in FVII deficient patients.

Blood stains of the Turin Shroud 2015: beyond personal hopes and limitations of techniques.

In the early '80s, evidence was provided that, rather than a dye (red okra), hemoglobin was indeed responsible for the alleged blood stains of the Turin Shroud. Such stains were shown to belong to an MNS positive individual of the AB group, and the halos surrounding the blood stains were compatible with serum containing trace amounts of bilirubin, albumin and immunoglobulins. However, being only based on indirect and circumstantial evidence, most of these data were challenged. In the late '90s, together with the evidence of the gene coding ß-globin, contamination between male and female DNA was documented on the Turin Shroud. Although the presence of male was more noticeable than female DNA, these data were considered null and void. These days, to establish that blood indisputably belongs to an MNS positive individual of the AB group, and to exclude DNA contamination, high-specificity techniques with monoclonal antibodies and molecular studies on nuclear and mitochondrial DNA are needed. Indeed, consistent with DNA contamination on the Turin Shroud, sequences from multiple subjects of different ethnic origins have been recently detected on the human mitochondrial genome extracted from dust particles of the linen. Innovative concepts are likely to come up using modern research approaches to evaluate the issue of blood stains of the Turin Shroud. Nor can we rule out the possibility that religious implications of the new findings on the Turin Shroud might be envisaged. Conceivably enough, the ongoing debate will be fierce and passionate, especially in the media.

[New oral anticoagulants: recommendations, precautions and perspectives for use]. / I nuovi anticoagulanti orali: raccomandazioni, precauzioni e prospettive d'uso.

In phase III studies, some oral inhibitors of both thrombin (dabigatran etexilate) and activated factor X (rivaroxaban, apixaban) have been employed as new anticoagulant drugs in patients with atrial fibrillation or acute coronary syndromes. Such new drugs have overcome a series of limitations of the standard-of-care warfarin, and argue for the possibility of an easy, widespread use of anticoagulation in vascular medicine. However, to this end, we need information on management of bleeding in patients receiving these drugs. Dabigatran etexilate, rivaroxaban and apixaban affect major laboratory tests for clotting. However, at present we do not know whether and how this information may be clinically useful. Their high cost is another major issue, and newer pharmacoeconomic studies are needed to evaluate their cost-effectiveness ratio vs warfarin.