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SummaryThe molecular mechanisms that finely co-ordinate fibrin formation and fibrinolysis are now well defined. The structure and function of all major fibrinolytic proteins, which include serine proteases, their inhibitors, activators and receptors, have been characterized. Measurements of real time, dynamic molecular interactions during fibrinolysis of whole blood clots can now be carried out in vitro. The development of genetargeted mice deficient in one or more fibrinolytic protein(s) has demonstrated expected and unexpected roles for these proteins in both intravascular and extravascular settings. In addition, genetic analysis of human deficiency syndromes has revealed specific mutations that result in human disorders that are reflective of either fibrinolytic deficiency or excess. Elucidation of the fine control of fibrinolysis under different physiological and pathological haemostatic states will undoubtedly lead to novel therapeutic interventions. Here, we review the fundamental features of intravascular plasmin generation, and consider the major clinical syndromes resulting from abnormalities in fibrinolysis.

Austrian Science Fund, Austrian National Bank Memorial Fund, and participating hospitals.

The association of thrombosis and gestational morbidity with antiphospholipid antibodies is termed antiphospholipid syndrome (APS). Annexin 2 (A2) is a profibrinolytic endothelial cell surface receptor that binds plasminogen, its tissue activator (tPA), and beta(2)-glycoprotein I (beta2GPI), the main antigen for antiphospholipid antibodies. Here, we evaluate A2 as a target antigen in APS. Serum samples from 434 individuals (206 patients with systemic lupus erythematosus without thrombosis, 62 with APS, 21 with nonautoimmune thrombosis, and 145 healthy individuals) were analyzed by enzyme-linked immunosorbent assay (ELISA) and immunoblot for antiphospholipid and A2 antibodies. Anti-A2 antibodies (titer > 3 SDs) were significantly more prevalent in patients with APS (22.6%; venous, 17.5%; arterial, 34.3%; and mixed thrombosis, 40.4%) than in healthy individuals (2.1%, P < .001), patients with nonautoimmune thrombosis (0%, P = .017), or patients with lupus without thrombosis (6.3%, P < .001). Anti-A2 IgG enhanced the expression of tissue factor on endothelial cells (6.4-fold +/- 0.13-fold SE), blocked A2-supported plasmin generation in a tPA-dependent generation assay (19%-71%) independently of beta2GPI, and inhibited cell surface plasmin generation on human umbilical vein endothelial cells (HUVECs) by 34% to 83%. We propose that anti-A2 antibodies contribute to the prothrombotic diathesis in antiphospholipid syndrome.

Since its discovery as a src kinase substrate more than three decades ago, appreciation for the physiologic functions of annexin A2 and its associated proteins has increased dramatically. With its binding partner S100A10 (p11), A2 forms a cell surface complex that regulates generation of the primary fibrinolytic protease, plasmin, and is dynamically regulated in settings of hemostasis and thrombosis. In addition, the complex is transcriptionally upregulated in hypoxia and promotes pathologic neoangiogenesis in the tissues such as the retina. Dysregulation of both A2 and p11 has been reported in examples of rodent and human cancer. Intracellularly, A2 plays a critical role in endosomal repair in postarthroplastic osteolysis, and intracellular p11 regulates serotonin receptor activity in psychiatric mood disorders. In human studies, the A2 system contributes to the coagulopathy of acute promyelocytic leukemia, and is a target of high-titer autoantibodies in patients with antiphospholipid syndrome, cerebral thrombosis, and possibly preeclampsia. Polymorphisms in the human ANXA2 gene have been associated with stroke and avascular osteonecrosis of bone, two severe complications of sickle cell disease. Together, these new findings suggest that manipulation of the annexin A2/S100A10 system may offer promising new avenues for treatment of a spectrum of human disorders.

ObjectiveTo investigate the predictive factors for the development of Kaposi sarcoma-related immune reconstitution inflammatory syndrome (KS-IRIS) and long-term prognosis in patients starting combined antiretroviral therapy (cART).MethodsWe studied a retrospective-cohort of consecutive antiretroviral-naïve patients with KS initiating cART from January 2005 to December 2011 and followed through June 2013. KS-IRIS was defined as ≥2 of the following: abrupt increase in number of KS lesions, appearance or exacerbation of lung-opacities or lymphedema, concomitantly with an increase in CD4+ cell-count ≥50 cells/mm3 and a decrease of >1 log in viral-load once started cART. We compared individuals who met KS-IRIS criteria with those that did not and described the long-term follow-up.ResultsWe included 89 patients, 88 males; 35 (39%) developed KS-IRIS at a median of 10 weeks (IQR 4–16). KS-IRIS patients had more pulmonary-involvement (60% vs. 16.6% of patients; p < 0.0001), eight died attributed to pulmonary-KS. Thrombocytopenia <100,000/mm3 at follow-up occurred in 36% of KS-IRIS vs. 4% in non-KS-IRIS patients (p = 0.0002), 45% KS-IRIS patients with thrombocytopenia died, non without KS-IRIS. Chemotherapy (bleomicyn–vincristine) was more frequently prescribed in KS-IRIS patients (88.6% vs. 29.6%) with no differences in outcome; 80% of all patients achieve KS complete remission, 52% of them never received chemotherapy. No difference between groups in the long-term follow-up (mean 52.4 ± 27.4 months) was found, only one patient developed a secondary malignancy (1.12%).ConclusionsLung-involvement was predictive of IRIS development. Thrombocytopenia in KS-IRIS patients at week 12 follow-up after cART initiation was associated with high mortality. Over a third of patients with KS achieve remission without chemotherapy. Individuals that survive the initial period of KS-IRIS adhere to cART had a good long-term prognosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12981-017-0156-9) contains supplementary material, which is available to authorized users.

Oncolytic virotherapy has been investigated for several decades and is emerging as a plausible biological therapy with several ongoing clinical trials and two viruses are now approved for cancer treatment in humans. The direct cytotoxicity and immune-stimulatory effects make oncolytic viruses an interesting strategy for cancer treatment. In this review, we summarize the results of in vitro and in vivo published studies of oncolytic viruses in different phases of evaluation in dogs, using PubMed and Google scholar as search platforms, without time restrictions (to date). Natural and genetically modified oncolytic viruses were evaluated with some encouraging results. The most studied viruses to date are the reovirus, myxoma virus, and vaccinia, tested mostly in solid tumors such as osteosarcomas, mammary gland tumors, soft tissue sarcomas, and mastocytomas. Although the results are promising, there are issues that need addressing such as ensuring tumor specificity, developing optimal dosing, circumventing preexisting antibodies from previous exposure or the development of antibodies during treatment, and assuring a reasonable safety profile, all of which are required in order to make this approach a successful therapy in dogs.

Introduction: Venous thromboembolism (VTE) is a leading cause of cardiovascular morbidity and mortality. The majority of VTE events are hospital-associated. In 2008, the Epidemiologic International Day for the Evaluation of Patients at Risk for Venous Thromboembolism in the Acute Hospital Care Setting (ENDORSE) multinational