Wpływ oligomerów procyanidolowych na aktywność antykoagulacyjną osocza

Background. Procyanidolic oligomers (PO) inhibit the degradation of subendothelial connective tissue by collagenase and elastase neutralization. Their efficacy in postphlebitic syndrome and venous insufficiency may suggest an additional systemic action mediated by endothelium. Therefore, the plasma anticoagulant response and the tissue plasma pathway inhibitor (TFPI) release induced by PO was assessed. Material and methods. Twenty-six patients, both surgical and medical, aged 29–86 years, who required antithrombotic prophylaxis for at least 5 days, were included in the study. The patients with higher thrombotic risk received either unfractionated heparin (UFH; 5000 IU bid, s.c., n = 8) or low molecular weight heparin (LMWH; 2850 IU AXa/0.3 mL o.d, s.c., n = 8). The patients with lower thrombotic risk received PO (150 mg bid, p.o., n = 10). In the control group there were age- and sex-matched healthy volunteers, to whom a placebo was administered. Blood samples were drawn before, on the 1, 4, 8 h, as well as on the days 2, 5 after administration of the study medication. Results. The TFPI concentration did not change significantly from the baseline value at any time, either in patients or in controls. Anti-Xa activity increased at 1 h until day 5 after administration of each study medication. Anti-IIa activity increased at 1 hour and remained elevated until day 5 under UFH and LMWH treatment, but only until day 2 in the PO group. The area under the curve of both anti-Xa and anti-IIa activity was similar in all three study groups but significantly larger as compared to the controls. Conclusions. Procyanidolic oligomers, like heparin and LMWH, induce anticoagulant response in plasma, but do not release TFPI into the blood.Wstęp. Oligomery procyanidolowe (PO) hamują degradację podśródbłonkowej tkanki łącznej poprzez neutralizację kolagenazy i elastazy. Skuteczność PO w zespole pozakrzepowym i niewydolności żylnej może sugerować ich dodatkowe działanie układowe, w którym pośredniczy śródbłonek. Było to przesłanką do oceny odpowiedzi antykoagulacyjnej osocza wywoływanej przez PO i uwalniania inhibitora drogi zewnątrzpochodnej (TFPI). Materiał i metody. Do badania włączono 26 chorych z oddziałów chirurgicznego i internistycznego w wieku 29–86 lat, u których konieczne było zastosowanie profilaktycznej terapii przeciwzakrzepowej przez co najmniej 5 dni. Chorzy z dużym ryzykiem zakrzepowym otrzymywali albo heparynę niefrakcjonowaną (UFH; 5000 jm. dwa razy dziennie podskórnie, n = 8), albo heparynę drobnocząsteczkową (LMWH; 2850 jm. AXa/0,3 ml raz dziennie podskórnie, n = 8). Pacjenci, u których ryzyko zakrzepowe było małe, otrzymywali PO (150 mg dwa razy dziennie doustnie, n = 10). Grupę kontrolną stanowili zdrowi ochotnicy zaklasyfikowani według wieku i płci, otrzymujący placebo. Krew do badań pobierano przed podaniem leku oraz w 1., 4. i 8. godzinie oraz w 2. i 5. dniu od podania leku. Wyniki. Stężenie TFPI nie zmieniało się w porównaniu z wartością wyjściową zarówno w grupach badanych, jak i kontrolnej. Aktywność anty-Xa zwiększała się od 1. godziny do 5. dnia po podaniu każdego leku. Aktywność anty-IIa była zwiększona od 1. godziny do 5. dnia po podaniu UFH i LMWH, ale tylko do 2. dnia po PO. Całkowita aktywność anty-Xa i anty-IIa, oceniana jako wielkość pola pod krzywą w badanym czasie, była podobna we wszystkich grupach badanych, ale znacząco wyższa w porównaniu z grupą kontrolną. Wnioski. Oligomery procyanidolowe, podobnie jak heparyna niefrakcjonowana i drobnocząsteczkowa, wywołują odpowiedź antykoagulacyjną w osoczu, ale nie powodują uwalniania TFPI do krwi

Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial

IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved

Cadmium-Induced Oxidative Stress and Apoptotic Changes in the Testis of Freshwater Crab, Sinopotamon henanense

Cadmium (Cd), one of the most toxic environmental and industrial pollutants, is known to exert gonadotoxic and spermiotoxic effects. In the present study, we examined the toxic effect of Cd on the testis of freshwater crab, Sinopotamon henanense. Crabs were exposed to different Cd concentrations (from 0 to 116.00 mg·L−1) for 7 d. Oxidative stress and apoptotic changes in the testes were detected. The activities of SOD, GPx and CAT initially increased and subsequently decreased with increasing Cd concentrations, which was accompanied with the increase in malondialdehyde (MDA) and H2O2 content in a concentration-dependent manner. Typical morphological characteristic and physiological changes of apoptosis were observed using a variety of methods (HE staining, AO/EB double fluorescent staining, Transmission Electron Microscope observation and DNA fragmentation analysis), and the activities of caspase-3 and caspase-9 were increased in a concentration-dependent manner after Cd exposure. These results led to the conclusion that Cd could induced oxidative damage as well as apoptosis in the testis, and the apoptotic processes may be mediated via mitochondria-dependent apoptosis pathway by regulating the activities of caspase-3 and caspase-9

Amyloids - A functional coat for microorganisms

Amyloids are filamentous protein structures ~10 nm wide and 0.1–10 µm long that share a structural motif, the cross-β structure. These fibrils are usually associated with degenerative diseases in mammals. However, recent research has shown that these proteins are also expressed on bacterial and fungal cell surfaces. Microbial amyloids are important in mediating mechanical invasion of abiotic and biotic substrates. In animal hosts, evidence indicates that these protein structures also contribute to colonization by activating host proteases that are involved in haemostasis, inflammation and remodelling of the extracellular matrix. Activation of proteases by amyloids is also implicated in modulating blood coagulation, resulting in potentially life-threatening complications.

Influence of acetylsalicylic acid on hematotoxicity of benzene

Objectives: The aim of the study was to evaluate the influence of acetylsalicylic acid (ASA) on benzene hematotoxicity in rats. Materials and Methods: The study was carried out on rats exposed for 2, 4 and 8 weeks to benzene vapour at a conentration of 1.5 or 4.5 mmol/m3 of air (5 days per week, 6 hours per day) alone or together with ASA at the doses of 5, 150 or 300 mg/kg body weight (per os). Results: Benzene at a concentration of 4.5 mmol/m3 caused a slight lymphopenia, granulocytosis and reticulocytosis in blood. In bone marrow traits of megaloblastic renewal, presence of undifferentiated cells and giant forms of granulocytes as well as an increase in myeloperoxidase and decrease in chloroacetate esterase activity and lipids content were noted. ASA (150 and 300 mg/kg b.w.) influenced some of hematological parameters, altered by benzene intoxication. ASA limited the solvent-induced alteration in blood reticulocyte count and in the case of bone marrow in the erythroblasts count. Traits of megaloblastic renewal in bone marrow were less pronounced. Besides, higher activity of myeloperoxidase and the decrease in the level of lipids in granulocytes were noted. Conclusion: Our results suggest that ASA limited the benzene-induced hematotoxicity

Rare-Earth Doped Nanocrystalline Phosphors for Field Emission Displays

The cathodoluminescence properties of rare-earth (RE = Ce, Eu, Tb) doped nanocrystalline phosphors (Y2O3, Y3Al5O12) were investigated. Their structure and morphology were determined and correlated with optical properties. The effect of grain sizes on emission yield of RE doped nanophosphors has been investigated. A possibility of application of RE doped nanophosphors for efficient field emission display (FED) devices has been discussed

Profound thrombocytopenia after abciximab administration in acute myocardial infarction and stent thrombosis following thrombocytopenia remission - a case report

Profound thrombocytopenia after abciximab administration in acute myocardial infarction and stent thrombosis: This article presents a case of a 62-years-old man with acute anterior myocardial infarction, treated with PCI and stent implantation, in whom profound acute thrombocytopenia was observed after abciximab administration. Nadir platelet count was 6 G/L (before treatment: 250 G/L). Pseudothrombocytopenia was excluded. The remaining antiplatelet drugs (heparin, ASA, clopidogrel) were discontinued. There were no symptoms of bleeding, but next morning (platelet count: 14 G/L) a gross hematoma at femoral puncture site was observed. The patient received 5 U transfusion of platelets. On the 4th day, when the platelet count reached 64 G/L, he was started again on ASA (150 mg) and clopidogrel (75 mg). On the 7th day (platelet count: 138 G/L) he developed anterior ischemia and stent reocclusion was diagnosed. After p.o. clopidogrel (300 mg), balloon PCI with i.c. heparin was performed and ischemia symptoms subsided. The platelet value before the patient's discharge, on subsequent therapy with ASA and clopidogrel, increased to 300 G/L. A review of current literature on this topic is provided

Influence of acetylsalicylic acid on hematotoxicity of benzene

Objectives: The aim of the study was to evaluate the influence of acetylsalicylic acid (ASA) on benzene hematotoxicity in rats. Materials and Methods: The study was carried out on rats exposed for 2, 4 and 8 weeks to benzene vapour at a conentration of 1.5 or 4.5 mmol/m3 of air (5 days per week, 6 hours per day) alone or together with ASA at the doses of 5, 150 or 300 mg/kg body weight (per os). Results: Benzene at a concentration of 4.5 mmol/m3 caused a slight lymphopenia, granulocytosis and reticulocytosis in blood. In bone marrow traits of megaloblastic renewal, presence of undifferentiated cells and giant forms of granulocytes as well as an increase in myeloperoxidase and decrease in chloroacetate esterase activity and lipids content were noted. ASA (150 and 300 mg/kg b.w.) influenced some of hematological parameters, altered by benzene intoxication. ASA limited the solvent-induced alteration in blood reticulocyte count and in the case of bone marrow in the erythroblasts count. Traits of megaloblastic renewal in bone marrow were less pronounced. Besides, higher activity of myeloperoxidase and the decrease in the level of lipids in granulocytes were noted. Conclusion: Our results suggest that ASA limited the benzene-induced hematotoxicity

Elevation of plasma fibrinogen in silent myocardial ischaemia

High plasma levels of fibrinogen and plasminogen activator inhibitor (PAI-1) are reported to be correlated with coronary heart disease. Therefore the level of fibrinogen concentration in plasma was examined and verified for the possible correlation with the previously explored PAI-1 antigen and PAI-1 activity in the pathogenesis of premature atherosclerosis (Grzywaczet al., 1998,Blood Coagul Fibrinol. 9, 245-249). Examination included only men, aged 33-46 years, who were in a stable condition for at least six months after the acute event. They were divided into two subgroups: group A (n = 14)  with and group B (n = 15) without ischaemic changes in 24 h Holter electrocardiogram. The number of involved vessels visible on the coronarography picture was similar in both groups. In the patients of group A the mean level of fibrinogen (3.92 vs 3.23 g/l, P < 0.05) was higher than in the controls (n = 15). No statistically differences were found between group B and control healthy subjects in any of the parameters measured. There were no correlation between fibrinogen concentration and PAI-1 antigen and activity levels, which were elevated in both groups of patients according to our previous study. Our results indicate that elevated levels of plasma fibrinogen and PAI-1 appeared in the group of patients with more severe disease, as revealed by silent myocardial ischaemia