Pharmacological Correction of Cisplatin-Induced Hemostatic Disorders.

A single intraperitoneal administration of cisplatin in the MTD to outbred female mice disturbed hemostasis and formed the procoagulant phenotype of hemostatic potential on days 7-10 culminating in a pronounced hypocoagulation on day 15. Hemostasis was corrected with warfarin and an extract containing furocoumarins composed of isopimpinellin (42.97%), bergapten (35.18%), and xanthotoxin (15.41%). The extract was standardized with gas chromatography-mass spectrometry, thin-layer chromatography, and HPLC. Furocoumarins and reference drug warfarin were administered intragastrically during 4 days starting on day 6 after the administration of cisplatin. Both furocoumarins and warfarin corrected hypercoagulation on days 7-10. On day 10, furocoumarins normalized coagulation, whereas warfarin resulted in hypocoagulation. On days 15-30, no effects of warfarin were observed. furocoumarins corrected hypocoagulation on days 15-20 with prolongation of this effect up to experimental day 30.

Rationale for the Role of Heparin and Related GAG Antithrombotics in COVID-19 Infection.

The SARS-CoV-2 pandemic has focused attention on prevention, restriction and treatment methods that are acceptable worldwide. This means that they should be simple and inexpensive. This review examines the possible role of glycosaminoglycan (GAG) antithrombotics in the treatment of COVID-19. The pathophysiology of this disease reveals a complex interplay between the hemostatic and immune systems that can be readily disrupted by SARS-CoV-2. Some of the GAG antithrombotics also possess immune-modulatory actions and since they are relatively inexpensive they could play an important role in the management of COVID-19 and its complications.

Therapeutic Potential of Resveratrol in COVID-19-Associated Hemostatic Disorders.

Coagulation disorders, endotheliopathy and inflammation are the most common hallmarks in SARS-CoV-2 infection, largely determining COVID-19's outcome and severity. Dysfunctions of endothelial cells and platelets are tightly linked in contributing to the systemic inflammatory response that appears to be both a cause and a consequence of COVID-19-associated coagulation disorders and thrombotic events. Indeed, elevated levels of circulating inflammatory cytokines are often associated with abnormal coagulation parameters in COVID-19 patients. Although treatments with low molecular weight heparin (LMWH) have shown beneficial effects in decreasing patient mortality with severe COVID-19, additional therapeutic strategies are urgently needed. Utilizing the anti-inflammatory and anti-thrombotic properties of natural compounds may provide alternative therapeutic approaches to prevent or reduce the risk factors associated with pre-existing conditions and comorbidities that can worsen COVID-19 patients' outcomes. In this regard, resveratrol, a natural compound found in several plants and fruits such as grapes, blueberries and cranberries, may represent a promising coadjuvant for the prevention and treatment of COVID-19. By virtue of its anti-thrombotic and anti-inflammatory properties, resveratrol would be expected to lower COVID-19-associated mortality, which is well known to be increased by thrombosis and inflammation. This review analyzes and discusses resveratrol's ability to modulate vascular hemostasis at different levels targeting both primary hemostasis (interfering with platelet activation and aggregation) and secondary hemostasis (modulating factors involved in coagulation cascade).

Experience with Saccharomyces boulardii Probiotic in Oncohaematological Patients.

Very few reports have been published to date on the bloodstream infections caused by Saccharomyces spp. in oncohaematological patients, and there are no guidelines on the use of this probiotic microorganism in this population. We describe the use of probiotic preparation containing Saccharomyces boulardii in a large group of oncohaematological patients. We retrospectively analysed the data from 32,000 patient hospitalisations at the haematological centre during 2011-2013 (including 196 haematopoietic stem cell transplant recipients) in a tertiary care university-affiliated hospital. During the study period, 2270 doses of Saccharomyces boulardii probiotic were administered to the oncohaematological patients. In total, 2816 mycological cultures were performed, out of which 772 (27.4%) were positive, with 52 indicating digestive tract colonisation by Saccharomyces spp., mainly in patients with acute myeloid leukaemia (AML), myelodysplastic syndrome (MDS) or multiple myeloma (MM). While colonised, they were hospitalised for 1683 days and 416 microbiological cultures of their clinical samples were performed. In the studied group of patients, there were six blood cultures positive for fungi; however, they comprised Candida species: two C. glabrata, one C. albicans, one C. krusei, one C. tropicalis and one C. parapsilosis. There was no blood culture positive for Saccharomyces spp. Our study indicates that despite colonisation of many oncohaematological patients with Saccharomyces spp., there were no cases of fungal sepsis caused by this species.

Late-onset neutropenia after rituximab therapy in patients with autoimmune thrombotic and hemostatic disorders: a single center analysis.

Autoimmune thrombotic and hemostatic disorders, caused by autoantibodies against various factors regulating thrombosis and hemostasis, are rare. Rituximab (RTX) is on occasion used for treating these disorders. Late-onset neutropenia (LON) has been described as a side effect of RTX treatment for patients with hemato-oncological and/or rheumatological diseases but not for those with autoimmune thrombotic and hemostatic disorders. Eleven patients with autoimmune thrombotic and hemostatic disorders received RTX in our institution. Four of these 11 cases (36.4%) developed LON after a median 72.6 days of RTX administration (range 43-122). Three cases required G-CSF, but no severe infections developed.

Expression and partial biochemical characterization of a recombinant serine protease from Bothrops pauloensis snake venom.

Snake venom serine proteases (SVSPs) are enzymes capable of interfering at several points of hemostasis. Some serine proteases present thrombin-like activity, which makes them targets for the development of therapeutics agents in the treatment of many hemostatic disorders. In this study, a recombinant thrombin-like serine protease, denominated rBpSP-II, was obtained from cDNA of the Bothrops pauloensis venom gland and was characterized enzymatically and biochemically. The enzyme rBpSP-II showed clotting activity on bovine plasma and proteolytic activity on fibrinogen, cleaving exclusively the Aα chain. The evaluation of rBpSP-II activity on chromogenic substrates demonstrated thrombin-like activity of the enzyme due to its capacity to hydrolyze the thrombin substrate. These characteristics make rBpSP-II an attractive molecule for additional studies. Further research is needed to verify whether rBpSP-II can serve as a template for the synthesis of therapeutic agents to treat hemostatic disorders.

Hemostatic Disorders in Hormonally Active Pituitary Tumors.

Endocrinopathies encompass heterogeneous diseases that can lead to hemostasis disorders at various stages over their clinical course. Normal hemostasis requires an equilibrium between the processes of coagulation and fibrinolysis, which depend on multiple activators and inhibitors. To date, the influence of various hormonal disorders on the hemostatic system has been assessed many times. The aim of this review was to analyze hemostasis abnormalities that occur in patients with hormonally active pituitary tumors: corticotropinoma, somatotropinoma, prolactinoma, gonadotropinoma and thyrotropinoma. Authors discuss studies that examined coagulation and hemostasis parameters among patients with these tumors, as well as analyze antithrombotic prophylaxis approach for endogenous hypercortisolemia subjects in particular.

Pleiotropic effects of PPARγ agonist on hemostatic activation in type 2 diabetes mellitus.

Thiazolidinediones (TZDs) represent a class of peroxisome proliferator-activated receptor (PPAR)γ agonists widely used as insulin-sensitizers in the treatment of type 2 diabetes mellitus (T2DM). The beneficial effects of hypoglycemic drugs, including TZDs, on the hemostatic abnormalities associated to T2DM have been formerly related to improved metabolic control, rather than to direct effects. However, in recent years the pleiotropic effects of PPARγ agonists on hemostatic function have become evident. In particular, the role of platelets as a pivotal player in diabetes complications by stimulating and sustaining inflammation has been lately acknowledged. Upon activation platelets synthesize and release many bioactive substances such as thromboxane A2 (TXA2) or pro-inflammatory mediators including CD40 ligand (CD40L) that exert autocrine and paracrine activation processes in vascular inflammation leading to cardiovascular disease (CVD). Although PPARγ is a nuclear hormone receptor, anucleate platelets also highly express this receptor and treatment with synthetic PPARγ ligands dampens the release of soluble(s)CD40L and TXA2 in thrombin-activated platelets. Moreover, PPARγ through Sirtuin1 pathway has been implicated in modulating inflammatory and atherosclerotic processes in patients with T2DM. Therefore, in T2DM, where platelet activation contributes to the pathogenesis of CVD, TZDs may have an enhanced therapeutic role, despite some potentially serious adverse side effects. This review will discuss the pleiotropic effects of PPARγ treatment on the hemostatic abnormalities associated with T2DM, with particular focus on platelet activation.

Coagulopathies in the PICU: DIC and liver disease.

Bleeding in patients in pediatric intensive care units is associated with an increased risk of mortality. Fortunately, most patients with an abnormal coagulation profile do not bleed because this is generally secondary to liver disease or dietary-induced vitamin K deficiency. When the laboratory markers of coagulopathy are the result of disseminated intravascular coagulation, bleeding is common and the risk of mortality extreme. Although interventions directed toward correcting the abnormal coagulation test results are generally initiated, they are also generally either not warranted or not fully successful.

Haemostatic effects of levothyroxine and selenomethionine in euthyroid patients with Hashimoto's thyroiditis.

The aim of this prospective study was to investigate for the first time whether levothyroxine and selenomethionine, administered alone or in combination, affect coagulation and fibrinolysis in Hashimoto's thyroiditis patients with normal thyroid function tests. A group of 155 ambulatory women with recently diagnosed and previously untreated Hashimoto's thyroiditis, of whom 149 completed the study, were randomly assigned in a double-blind fashion to six months of treatment with levothyroxine, selenomethionine, levothyroxine plus selenomethionine, or placebo. The control group included 39 matched healthy women. The prothrombin time ratio, the activated partial thromboplastin time, and plasma levels/activities of fibrinogen, factor VII, von Willebrand factor, factor X and plasminogen activator inhibitor-1 (PAI-1) were assessed at baseline and after three and six months of treatment. Compared with the healthy subjects, Hashimoto's thyroiditis patients exhibited higher plasma levels/activities of all of the parameters studied, as well as were characterised by the abnormal prothrombin time ratio and activated partial thromboplastin time. All these haemostatic disturbances were reduced or normalised by levothyroxine + selenomethionine treatment, while the effect of levothyroxine or selenomethionine was limited to fibrinogen and PAI-1, respectively. Our results demonstrate that euthyroid women with Hashimoto's thyroiditis are characterised by abnormal coagulation and fibrinolysis. Levothyroxine and selenomethionine, especially if administered together, produce a beneficial effect on haemostasis in euthyroid patients with this disorder.

Monitoring unfractionated heparin therapy in dogs by measuring thrombin generation.

BACKGROUND: The calibrated automated thrombogram (CAT), an assay that permits measurement of thrombin generation in plasma, may be useful in studying hemostatic disorders and anticoagulant therapy in animals. OBJECTIVES: The aims of the study were to measure thrombin generation in healthy Beagle dogs and to evaluate the potential use of the CAT assay for monitoring therapy with unfractionated heparin (UFH). METHODS: Individual platelet-poor plasma samples and a plasma pool from 20 healthy adult Beagles were prepared. Serial UFH plasma dilutions were used to establish an in vitro heparin-sensitivity curve. The pharmacodynamic effects of heparin in vivo were evaluated in Beagles using the CAT assay to measure thrombin generation with tissue factor at a concentration of 5 pM for initiation. RESULTS: In healthy Beagles, the range of endogenous thrombin potential (ETP) was 238.7-414.0 nM/min (mean ± SD, 340.4 ± 63.1 nM/min). ETP intra-assay and interassay variations were 7.1% and 12.9%, respectively. In vitro, a UFH concentration ≥0.4 U/mL resulted in total inhibition of thrombin generation. In vivo, the maximal effect of UFH on ETP was observed at 170 ± 36 minutes (range, 120-210 minutes) and resulted in a decrease in ETP of 38.5 ± 7.8% (range, 26.5-50.3%). In 210-420 minutes, ETP returned to baseline in 5 dogs. CONCLUSION: Our study demonstrates that thrombin generation can be measured in canine plasma and may be useful in assessing the degree of anticoagulation provided by UFH.

[Specificities of neonatal hemostasis and implications in pathologic situations]. / Particularités de l'hémostase chez le nouveau-né et implications en pathologie.

The haemostasis of healthy newborn differs from those of normal adult but remains well balanced without bleeding or thrombosis. However, this equilibrium is unstable, and the neonate is exposed to acquired or inherited haemostasis disorders that necessitate to be early diagnosed in order to be appropriately treated. Several studies provided reference ranges for haemostatic components in the foetus, the newborn and throughout childhood. The particularities of neonatal haemostasis are therefore better defined and contribute to further understand the pathophysiology and characteristics of hemorrhagic and thrombotic disorders that occur in newborns. Some examples of the impact of age on haemostasis are: the risk of neonatal alloimmune thrombocytopenia is high in the first newborn of a woman at risk since the involved antigens are fully expressed by foetal platelets; the newborn is at risk for vitamin K deficiency with bleeding due to poor transport of vitamin K across the placenta and low levels of coagulation factors II, VII, IX, X; the diagnosis of some inherited coagulation deficiencies can be difficult in the newborn due to physiologically low levels of coagulation factors; thrombotic events are rare in the healthy neonate, despite physiologically very low levels of several coagulation inhibitors; the pharmacokinetic and effects of antithrombotic agents are influenced by the specificities of haemostasis in neonates. This review will discuss about the foetal development of haemostasis until birth, and some implications regarding the pathophysiology, the diagnosis and the treatment of bleeding disorders in the human neonate.

Treatment of the critically ill patient with protein C: is it worth the cost?

INTRODUCTION: We have shown that low protein C levels predict poor survival up to five years in a general intensive care unit patient material and hypothesize that treatment with protein C is beneficial. The objectives were to calculate costs of protein C treatment, at best-case scenario, per statistical life saved. MATERIALS AND METHODS: Ninety-two patients with deranged global haemostatic tests admitted to the mixed surgical medical intensive care unit, Malmö University Hospital. We hypothesized that increasing protein C levels in patients with low levels would enhance survival to the same rate as a cohort with higher protein C. Number of statistical lives saved were estimated using survival analysis. Costs per life saved at 30days were calculated. RESULTS: Total costs per life saved in 2007 prices (upper limit of 95% CI) were calculated at euro 50,200 (recombinant activated protein C, drotrecogin alfa (activated), Xigris) and euro 46,000 (zymogen protein C, Ceprotin), which may be compared to the value of a statistical life (euro 937,000). CONCLUSIONS: Our theoretical model of converting a low protein C group to a higher protein C group by treating with activated protein C or the protein zymogen showed no major difference between the treatments in terms of costs, and that costs are lower than the value of a statistical life. Although our study has several caveats the results support the PROWESS study, in that patients with a very severe disease, having low protein C levels, may benefit from protein C treatment in a cost effective way.

Fucoidan extracted from Fucus evanescens brown algae corrects immunity and hemostasis disorders in experimental endotoxemia.

Fucoidan extracted from brown algae (Fucus evanescens) was used for correction of immunity and hemostasis disorders in experimental endotoxemia induced by injection of LPS. Fucoidan reduced the elevated levels of proinflammatory cytokines (TNF-alpha, IL-1, IL-6) and partially arrested hypercoagulation phenomena, thus improving animal resistance to LPS.

Use of the levonorgestrel-releasing intrauterine system in women with hemostatic disorders.

OBJECTIVE: To evaluate the use of the levonorgestrel-releasing intrauterine system (LNG-IUS) in women with known hemostatic disorders and abnormal uterine bleeding. DESIGN: Retrospective case series. SETTING: Tertiary medical center. PATIENT(S): Women with regular, heavy menstrual bleeding who have von Willebrand's disease and/or are receiving anticoagulation therapy for a thrombotic disorder. INTERVENTION(S): Levonorgestrel intrauterine system. MAIN OUTCOME MEASURE(S): Impact on menstrual bleeding and quality of life. RESULT(S): Seven women with hemostatic disorders who had used the LNG-IUS were identified. All 7 women completed the survey. Median age was 38 years (range 28-48 years). Six women were white, 1 woman was black. Four women had von Willebrand's disease. Four women were using anticoagulation, 3 warfarin, and 2 aspirin. One woman had both von Willebrand's disease and was heterozygous for factor V Leiden. All 7 women had heavy menstrual bleeding. After placement of the LNG-IUS, a decrease in number of bleeding days was seen in 71% of subjects (5 of 7), with overall median days reduced from 9 to 3 days. One subject discontinued use of the LNG-IUS because she desired pregnancy. Two subjects (29%) had no benefit from the LNG-IUS. Quality of life improved after placement of the LNG-IUS. CONCLUSION(S): The LNG-IUS seems to be an effective treatment for heavy menses in women with hemostatic disorders. Providers should consider this option for women with hemostatic disorders because it is safe and simple to use.

Tissue factor and factor VIIa as therapeutic targets in disorders of hemostasis.

For hemophilia patients with inhibitors against FVIII or FIX, the development of recombinant factor VIIa (rFVIIa) raises the possibility of a therapeutic alternative whose availability and convenience of treatment are comparable to those of FVIII or FIX. In support of this new concept for the treatment of bleeding episodes, pharmacological doses of FVIIa have been shown to induce hemostasis. Pharmacological doses of rFVIIa enhance thrombin generation on thrombin-activated platelets, thereby facilitating the formation of strong, well-structured fibrin plugs resistant to premature proteolysis. Modified rFVIIa molecules with a stronger hemostatic potential have been produced. Inhibition of the FVII-TF-dependent pathway (TFPI and rFVIIai) has been tried in attempts to prevent thrombosis, with promising results in animal models so far not confirmed in clinical trials.