bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnesium Inhibits Platelet Activity - An In Vitro Study
Authors: Ravn Hanne Berg , Vissinger Henrik , Dalby Kristensen Steen , Elkjcer Husted Steen
Published: July 2018

The in vitro effect of magnesium (Mg) on platelet aggregation and platelet release function was evaluated in healthy volunteers. Platelet aggregation was induced with collagen, ADP, or thrombin after incubation of the sample with saline or increasing concentrations of magnesium sulphate (MgSO4) (0.5-8.0 mM). Mg showed a dose-dependent inhibition of platelet aggregation in whole blood, platelet rich plasma and washed platelets. An antiaggregatory effect was also present with low Mg concentrations. Statistically significant inhibition of the mean aggregation response was obtained in 83% of the different media and agonists tested following the addition of 1.0 mM Mg. The remaining 17% were significantly inhibited with the addition of 2.0 mM Mg. The platelet synthesis of thromboxane A2 and release of beta-thrombo-globulin were also inhibited by Mg, in a dose-dependent manner. In order to evaluate if any of these effects were modified by conventional antithrombotic treatment with low-dose acetylsalicylic acid (ASA), volunteers were asked to meet on two consecutive days. On day 2 the participants were given 300 mg ASA orally, one hour prior to blood sampling. The Mg mediated effects were present independent of this pretreatment with ASA. Following stimulation with collagen a synergistic effect of Mg and ASA was demonstrated on platelet aggregation. The platelet inhibiting effect demonstrated in this study may in part explain the beneficial effect of Mg infusion in some patients with acute myocardial infarction. The effect of Mg infusion, given alone or administered simultaneously with ASA, should also be evaluated in other arterial thrombotic disease states.
Prevention of Early Reocclusion after Thrombolysis of Copper Coil-induced Thrombi in the Canine Carotid Artery: Comparison of PEG-Hirudin and Unfractionated Heparin
Authors: Rübsamen Klaus , Hornberger Wilfried
Published: July 2018

Cofactor-independent thrombin inhibitors as adjunctive treatment to thrombolysis have been found to enhance reperfusion and reduce the incidence of early reocclusion more effectively than heparins. However, all thrombin inhibitors presently available are rapidly cleared from the circulation which may cause rebound effects after cessation of treatment. To evaluate the effect of PEG-hirudin (LU 87981) a new, long acting derivative of hirudin as adjunctive treatment to rt-PA, a thrombotic occlusion of the carotid artery was induced in mongrel dogs by means of a copper coil. Vessel patency was continuously monitored with an electromagnetic flow probe. Thrombolysis of the occluded artery was induced by administration of 40 Μg × kg−1 + 240 Μg × kg−1 × h−1 rt-PA (low dose) or 80 Μg × kg−1 + 480 Μg × kg−1 × h−1 rt-PA (high dose). With high dose rt-PA treatment, patency was achieved in all animals within 50 min (range 24 to 75), with low dose rt-PA treatment only in 6 out of 8 animals after 73 min (range 26 to 117). Concomitant administration of PEG-hirudin (0.3 mg × kg−1 bolus + 0.15 mg × kg−1 × h−1 infusion) increased the incidence of reperfusion in the low dose rt-PA group to 100% while the reperfusion time was shortened from 73 min in the corresponding control group to 38 min (range 20 to 75 min) in the group given PEG-hirudin (p = 0.065, Mann-Whitney U-test). The carotid artery blood flow, which rapidly declined to zero within 18 to 27 min after discontinuing low or high dose rt-PA infusions remained at a sustained level for the whole observation period of 4 h only in the group given PEG-hirudin. Only one animal reoccluded after 229 min. Unfractionated heparin (UFH) given at a dose of 0.3 mg × kg−1 bolus + 0.3 mg × kg−1 × h−1 infusion did not improve the incidence of reperfusion or lower the incidence of reocclusion. Buccal bleeding time was prolonged after high dose rt-PA treatment and after low dose rt-PA with adjunctive UFH- or PEG-hirudin treatment. Buccal blood loss was not significantly affected by either treatment.

In conclusion, these experiments indicate that early reocclusion after thrombolysis can effectively be diminished by concomitant treatment with the long acting thrombin inhibitor PEG-hirudin with moderate effects on bleeding time and aPTT.
New Mutations Causing the Premature Termination of Translation in the A Subunit Gene of Coagulation Factor XIII
Authors: Kangsadalampai Sasichai , Farges-Berth Anne , Hande Çaglayan S , Board Philip G
Published: July 2018

The amplification of factor XIIIA subunit gene exons and heteroduplex analysis has been used to identify two new mutations that cause severe factor XIII deficiency. One mutation in a family of French origin results from a 4 bp deletion and leads to a premature termination of translation. The other mutation occurred in a Turkish family and results from a C → T transition that inserts a premature translation stop signal at codon 400. Both mutations alter restriction enzyme sites and can be readily detected in amplified exon DNA for genetic counselling or prenatal diagnosis. The new mutations reflect the extensive molecular heterogeneity of factor XIII deficiency.
Modulation of Plasma Fibrinogen Levels by Ticlopidine in Healthy Volunteers and Patients with Stable Angina Pectoris
Authors: de Maat Moniek P M , Arnold Alf E R , Buuren Stef van , Paul Wilson J H , Kluft Cornells
Published: July 2018

Elevated plasma fibrinogen levels are associated with an increased risk for cardiac events. Ticlopidine is a drug that inhibits the ADP-induced aggregation of blood platelets and it also has been described that ticlopidine can decrease the plasma fibrinogen level in patients with vascular diseases. The mechanism of this decrease has not yet been elucidated and therefore mechanisms that are known to affect fibrinogen levels were studied, viz. the acute phase reaction, total fibrin plus fibrinogen degradation (TDP) levels and the polymorphisms of the fibrinogen β-gene.

The fibrinogen lowering effect of ticlopidine was studied in 26 healthy volunteers, selected on genotype of the BclI polymorphism of the fibrinogen β-gene, and in 26 patients with stable angina pectoris in a double blind, randomized cross-over study. Functional plasma fibrinogen levels were measured with the Clauss assay. Fibrinogen antigen, C-reactive protein (CRP) and TDP levels were measured using an enzyme immuno assay (EIA).

In the healthy volunteers the functional fibrinogen levels had decreased by 0.20 g/l (9%, p = 0.005 using the paired Student t-test) after 4 weeks of 250 mg bid ticlopidine administration, whereas fibrinogen antigen, CRP and TDP levels were not significantly changed. In the stable angina pectoris patients the pre-treatment fibrinogen, CRP and TDP levels were significantly higher than in the volunteer group. After four weeks 250 mg bid ticlopidine administration the functional fibrinogen levels had decreased by 0.38 g/l (11%, p < 0.005), whereas the fibrinogen antigen, CRP and TDP levels were not significantly changed. The levels of functional and antigen fibrinogen, CRP and TDP did not change significantly during the placebo period in the volunteers or the patients. Neither in the volunteers nor in the patients was the effect of ticlopidine on the fibrinogen levels associated with the fibrinogen β-gene polymorphisms.

Therefore, the fibrinogen lowering effect of ticlopidine is likely to be a modulation of the functionality of the molecule and unlikely to be modulated by the acute phase reaction, TDP-levels or the fibrinogen β-gene polymorphisms.
Association between High Values of D-dimer and Tissue-plasminogen Activator Activity and First Gastrointestinal Bleeding in Cirrhotic Patients
Authors: Violi Francesco , Basili Stefania , Ferro Domenico , Quintarelli Claudio , Alessandri Cesare , Cordova Corrado ,   CALC Group
Published: July 2018

Cirrhotic patients with decompensated state and high serum levels of fibrin(ogen) degradation products are at high risk of bleeding. The aim of this study was to further analyse the relationship between hyperfibrinolysis and bleeding in cirrhosis by measuring plasma values of D-dimer and tissue plasminogen activator (t-PA) activity. One-hundred-twelve cirrhotic patients with oesophageal varices and without previous upper-gastrointestinal bleeding entered the study and were followed-up for 3 years. Patients were considered to have hyperfibrinolysis if they concomitantly had high values of D-dimer and t-PA activity. During the follow-up 34 (30%) patients bled. They had more severe liver failure (p = 0.0001) and variceal size (p = 0.0031) and higher prevalence of ascites (p = 0.0003), varices with red signs and hyperfibrinolysis (p = 0.0001) than patients who did not bleed. Multivariate analysis disclosed hyperfibrinolysis as the only marker predictive of bleeding (Hazard Ratio = 42.5, p <0.001). Our findings suggest that screening for hyperfibrinolysis may be useful to identify cirrhotic patients at risk of bleeding.
An Alternative Elastase-mediated Degradation of Fibrinogen and Fibrin Observed in a Patient with Herpes Simplex Encephalitis and Pneumonia
Authors: lijima Kenji , Murakami Fumiyo , Horie Yasushi , Nakamura Katsumi , Ikawa Shiro , Soe Gilbu , Kohno Isao , Nakayasu Hiroyuki , Shimomura Tokio , Takahashi Kazuro
Published: July 2018

A 74-year-old female developed pneumonia following herpes simplex encephalitis. Her white blood cell counts reached 28,400/μl, about 90% of which consisted of granulocytes. The polymorphonuclear (PMN) elastase/α1-arantitrypsin complex levels increased and reached the maximum of 5,019 ng/ml, indicating the release of a large amount of elastase derived from the granulocytes. The mechanism of PMN elastase release was most likely to be granulocyte destruction associated with phagocytosis. The cleavage of fibrinogen and fibrin by PMN elastase, independent of plasmin, was indicated by the presence of the fragments in immunoprecipitated plasma from the patient corresponding to elastase-induced FDP D and DD fragments and the absence of fragments corresponding to plasmin-induced FDP D and DD fragments on SDS-PAGE. These findings suggested that the large amount of PMN elastase released from the excessive numbers of granulocytes in this patient with herpes simplex encephalitis and pneumonia, induced the cleavage of fibrinogen and fibrin without the participation of plasmin.
The Propeptides of Human Protein C, Factor VII, and Factor IX Are Exchangeable with Regard to Directing Gamma-Carboxylation of these Proteins
Authors: Geng Jie-Ping , Castellino Francis J
Published: July 2018

The specificity of the propeptide sequence in directing vitamin Independent post-translational γ-carboxylation has been assessed by examination of the extent of processing of chimeric constructs of blood coagulation factor VII (fVII), factor IX (fIX) and protein C (PC). One chimera consisted of a protein in which the γ-carboxyglutamic acid (Gla)/helical stack domain of PC (amino acid residues 1 to 46) was replaced by that of fIX (residues 1 to 47) in an otherwise intact PC. Another consisted of the same construction of a fVII/PC Gla domain-based mutant protein. The final chimera contained the leader/propeptide sequence of PC (residues -42 to -1) replaced by that of fIX (residues -46 to -1). In each case, all Glu-precursor Gla residues in the Gla domains of the proteins were fully processed to Gla. These results demonstrate that the propeptides of fIX and PC are capable of directing γ-carboxylation of the Gla regions of either protein, that the propeptide of PC can fully function in γ-carboxylation of the Gla region of fVII, and further suggest that, with regard to γ-carboxylation, communications between the propeptides and Gla domains in intact proteins are general in nature.
β2 Glycoprotein-I Inhibits Factor XII Activation on Triglyceride Rich Lipoproteins: The Effect of Antibodies from Plasma of Patients with Antiphospholipid Syndrome
Authors: McNally T , Mackie I J , Isenberg D A , Machin S J
Published: July 2018

It is now well recognised that antiphospholipid antibodies are associated with thrombosis and recurrent fetal loss. Some antiphospholipid antibodies (aPAs) have been shown to require a cofactor, β2 glyco-protein-I (β2GPI), for binding to phospholipids, and recently β2GPI has been identified as the antigenic target for some aPAs. β2GPI possesses in vitro anticoagulant properties and modulation of β2GPI function may therefore result in altered haemostatic regulation. In the present study, the influence of plasma derived aPAs and β2GPI on factor XII activation on the surface of very low density lipoprotein (VLDL) was investigated. Factor XIIa generation was dependent on lipoprotein lipase treatment of VLDL and β2GPI inhibited the factor XIIa generation in a concentration dependent manner. No consistent effects on factor XIIa generation were demonstrated with the IgG fractions from patients with aPAs. Inhibition of the β2GPI activity was demonstrated by some antibodies, and study with cardiolipin affinity purified antibody indicated that antibody concentration is critical. These results suggest that perturbation of β2GPI function may contribute to the pathogenic mechanism for thrombosis in some patients with aPAs. .
Non Neutralizing Antibodies to Tissue Type Plasminogen Activator in the Serum of Acute Myocardial Infarction Patients Treated with the Recombinant Protein
Authors: Cugno Massimo , Cicardi Marco , Colucci Mario , Bisiani Giuliana , Angelica Merlini Piera , Spinola Alessandra , Paonessa Raffaella , Agostoni Angelo
Published: July 2018

Recombinant tissue-type plasminogen activator (rt-PA) is currently used as a thrombolytic agent in the management of acute myocardial infarction (AMI). Since it is known that other recombinant proteins induce antibody formation when administered to humans, we determined the presence of anti-rt-PA antibodies in serial blood samples from 60 AMI patients (43 treated with and 17 without rt-PA). Blood samples were taken upon hospital admission, 15 days and 1, 3,6 months thereafter. A blood sample was also collected from 200 healthy subjects. Using an ELISA, anti-rt-PA antibodies were detected as serum immunoglobulins specifically binding immobilized rt-PA. AMI patients before treatment and normal subjects exhibited negligible levels of anti-rt-PA antibodies; both groups had only one outlier value. Fifteen days after rt-PA treatment, 2 AMI patients showed an increase in antibody titer beyond the highest normal value. This titer progressively decreased during the following 6 months. The antibodies from these two patients bound rt-PA both in a solid and fluid phase. They bound melanoma t-PA to a lower degree and did not bind urokinase type plasminogen activator at all, indicating specificity for t-PA. The marked temporal relationship between rt-PA infusion and antibody appearance indicated that antibody formation had been elicited by the infusion of rt-PA. Nevertheless, the lack of anti-rt-PA antibody interference with rt-PA function in vitro, along with the favourable clinical outcome of those patients having such antibodies would indicate that the appearance of anti-rt-PA antibodies does not interfere with the physiological fibrinolytic activity.
Neointima Formation in Injured Hamster Carotid Artery Is Effectively Prevented by the Combination G4120 and Quinapril
Authors: Matsuno Hiroyuki , Marie Stassen Jean , Moons Lieve , Vermylen Jos , Hoylaerts Marc F
Published: July 2018

The prevention of neointima formation by the tissue selective angiotensin converting enzyme (ACE) inhibitor quinapril and by the combination quinapril/G4120 (a platelet αIIbβ3 and smooth muscle cell αvβ3 antagonist) was investigated in a hamster carotid artery injury model. Quinapril at 10 mg/kg/day reduced neointima formation by about 45%, 1 and 2 weeks after injury to the artery, i.e. significantly better than the non-tissue selective ACE inhibitor captopril at 100 mg/kg/day. Quinapril did not decrease the early smooth muscle cell (SMC) proliferation in the media, but in agreement with its inhibition of the carotid artery ACE activity by 62%, SMC proliferation was reduced by 70% in the newly forming intima. To improve the inhibition of early medial SMC proliferation, quinapril (10 mg/kg/day) was complemented with G4120 (100 Μg/kg/h). This combined treatment reduced the proliferation of medial SMCs to about 50% throughout the first week following injury, whereas intima SMC proliferation was reduced by 70% throughout treatment. Accordingly, the drug combination reduced neointima formation more potently than each drug separately by 70%. The disruption of medial elastic laminae, observed in the control and G4120 treated group, was consistently reduced when G4120 was complemented with quinapril. Thus, the present study shows in a hamster model of carotid artery injury, that combining drugs that prevent SMC migration and proliferation via different modes of action can lead to the effective prevention of neointima formation.
Two Recombinant Tissue Factor Reagents Compared to Conventional Thromboplastins for Determination of International Normalised Ratio: A Thirty-three-laboratory Collaborative Study
Authors: Kitchen S , Jennings I , Woods T A L , Walker I D , Preston F E ,   On behalf of the Steering Committee of the UK National External Quality Assessment Scheme for Blood Coagulation
Published: July 2018

Recent advances in recombinant technology have led to the development of prothrombin time (PT) reagents containing recombinant tissue factor which has been lipidated to allow expression of procoagulant activity. In this study we have compared International Normalised Ratios (INRs) determined using two such reagents and conventional thromboplastins in widespread use in the UK.

Lyophilised plasma samples from eight different warfarinised patients were distributed to 33 laboratories in the UK. Each participant determined prothrombin times on 20 local fresh normal plasmas (used to derive mean normal PT and calculate INR) and the eight lyophilised samples, using manual technique and the following thromboplastins; Recombiplastin (Ortho Diagnostics Ltd); Innovin (Baxter Diagnostics Ltd); the conventional thromboplastin in local use.

For eight plasmas the mean INRs determined with different reagents were as follows: Innovin (33 laboratories) - 3.4; Manchester Reagent (MR = 8 laboratories) - 3.4; Recombiplastin (33 laboratories) - 3.7; Instrumentation Laboratory (IL = 13 laboratories) - 4.4.

Mean INR results with Recombiplastin were on average 7% greater than those obtained with Innovin, 8% greater than results with MR and 18% less than INRs with IL thromboplastin. There was no significant difference between results obtained with Innovin and MR. In contrast INRs obtained with IL were markedly (mean 28%) greater than results obtained with Innovin.

This study employed lyophilised plasma and it is possible that some of the relationships described are influenced by this. However, the lyo-philisation process employed did not influence the relationship between INRs of warfarinised plasmas obtained by the four main reagents described, indicating that the results are relevant to routine clinical practice.

In conclusion, our data show some important differences are present between INRs determined using Recombiplastin, Innovin and two conventional thromboplastins.
A Prothrombinase-based Assay for Detection of Resistance to Activated Protein C
Authors: Nicolaes Gerry A F , Christella M , Thomassen L G D , Oerle Rene van , Hamulyak Karly , Hemker H Coenraad , Tans Guido , Rosing Jan
Published: July 2018

In this paper we present a new method for the detection of resistance to activated protein C (APC) that is based on direct measurement of the effect of APC on the cofactor activity of plasma factor Va. The factor V present in a diluted plasma sample was activated with thrombin and its sensitivity towards APC was subsequently determined by incubation with phospholipids and APC. The loss of factor Va cofactor activity was quantified in a prothrombinase system containing purified prothrombin, factor Xa and phospholipid vesicles and using a chromogen-ic assay for quantitation of thrombin formation. The reaction conditions were optimized in order to distinguish normal, heterozygous and homozygous APC-resistant plasmas. Maximal differences in the response of these plasmas towards APC were observed when factor Va was inactivated by APC in the absence of protein S and when the cofactor activity of factor Va was determined at a low factor Xa concentration (0.3 nM).

Addition of 0.2 nM APC and 20 μM phospholipid vesicles to a 1000-fold diluted sample of thrombin-activated normal plasma resulted in loss of more than 85% of the cofactor activity factor Va within 6 rnin. Under the same conditions, APC inactivated ∼ 60% and ∼20% of the factor Va present in plasma samples from APC-resistant individuals that were heterozygous or homozygous for the mutation Arg506⟶Gln in factor V, respectively. Discrimination between the plasma samples from normal and heterozygous and homozygous APC-resistant individuals was facilitated by introduction of the so-called APC-sensitivity ratio (APC-sr). The APC-sr was defined as the ratio of the factor Va cofactor activities determined in thrombin-activated plasma samples after 6 min incubation with or without 0.2 nM APC and was multiplied by 100 to obtain integers (APC-sr = {factor Va+APC/factor Va−APC} × 100). Clear differences were observed between the APC-sr of plasmas from normal healthy volunteers (APC-sr: 8-20, n = 33) and from individuals that were heterozygous (APC-sr: 35-50, n = 17) or homozygous APC resistant (APC-sr: 82-88, n = 7). There was no mutual overlap between the APC-sr of normal plasmas and plasmas from heterozygous or homozygous APC resistant individuals (p <0.0001). In all cases our test gave the same result as the DNA-based assay. Since the test is performed on a highly diluted plasma sample there is no interference by conditions that affect APC resistance tests that are based on clotting time determinations (e.g. coagulation factor deficiencies, oral anticoagulation, heparin treatment, the presence of lupus anticoagulants, pregnancy or the use of oral contraceptives). Furthermore, we show that part of the factor Va assay can be performed on an autoanalyzer which increases the number of plasma samples that can be handled simultaneously.
Agonist-induced Actin Polymerization Is Required for the Irreversibility of Platelet Aggregation
Authors: Torti Mauro , Tolnai Festetics Enrico , Bertoni Alessandro , Sinigaglia Fabiola , Balduini Cesare
Published: July 2018

Cytochalasin D was used to investigate the role of intracellular cyto-skeleton in the stabilization of platelet aggregation induced by strong platelet agonists. Incubation of gel-filtered platelets with increasing concentrations of cytochalasin D resulted in a dose-dependent inhibition of actin polymerization and association of actin-binding proteins with the Triton X-100-insoluble material induced by the thromboxane analogue, U46619, and the thrombin receptor activating peptide, TRAP. The same concentrations of cytochalasin D did not significantly inhibit platelet aggregation promoted by the two agonists. The addition of the chelating agent EDTA to fully aggregated platelets, that had been treated with cytochalasin D, resulted in the rapid and almost complete disaggregation. EDTA did not cause disaggregation of control, solvent-treated, aggregated platelets. The degree of platelet disaggregation induced by EDTA was dependent on the dose of cytochalasin D used, and was correlated with the inhibition of the cytoskeletal reorganization. Aggregation of cytochalasin D-treated platelets stimulated with U46619 or TRAP was also reverted by the addition of the tetrapeptide RGDS or the fibrinogen y-chain dodecapeptide, which competitively interfere with fibrinogen binding to the glycoprotein Ilb-IIIa complex. These results indicate that the intracellular cytoskeleton plays an essential role in the stabilization of the fibrinogen-platelet interaction, and is necessary for the irreversibility of platelet aggregation induced by strong agonists.
Antiplatelet Activity in Onion (Allium cepa) Is Sulfur Dependent
Authors: Goldman Irwin L , Kopelberg Murray , Debaene Jan E P , Schwartz Bradford S
Published: July 2018

Plants of the genus Allium such as onion and garlic are often consumed as a source of compounds which inhibit human platelet activity, with the goal of decreasing vascular disease. Antiplatelet activity in these plants is determined in part by native concentrations of organosul-fur compounds. Evaluation of four onion genotypes grown in a field study at four US locations in 1994 demonstrated onions with mild flavor and low sulfur content exhibited significantly lower antiplatelet activity than those containing high levels of sulfur. Antiplatelet activity was significantly positively correlated with genotypically determined bulb sulfur content and dissolved solids, indicating these latter factors are good predictors of antiplatelet strength. These data demonstrate antiplatelet activity is genotype dependent and correlated with bulb sulfur content. Genotype and bulb sulfur content should be taken into account in studies assessing onion antiplatelet effects.
A Multicenter Randomized Double-blind Study of Enoxaparin Compared with Unfractionated Heparin in the Prevention of Venous Thromboembolic Disease in Elderly In-patients Bedridden for an Acute Medical Illness
Authors: Bergmann Jean-Fraçois , Neuhart Eric
Published: July 2018

A multicenter, randomized double-blind study compared in two parallel groups the efficacy and safety of a low molecular weight heparin (LMWH) enoxaparin 20 mg once daily, with unfractionated heparin (UFH) 5000 IU twice daily, administered subcutaneously for 10 days, in the prevention of venous thrombosis disease in 442 hospitalized elderly patients bedridden for an acute medical illness. The main efficacy endpoint was defined as the occurrence of venous thrombosis, diagnosed by a daily fibrinogen uptake test, and/or documented clinical pulmonary embolism.

Intention-to-treat analysis of efficacy showed that the incidence of venous thromboembolic events was low: 4.8% (10/207) in the LMWH group (9 episodes of isotopic venous thrombosis and one of scintigraphic pulmonary embolism), and 4.6% (10/216) in the UFH group (10 episodes of isotopic venous thrombosis). The two treatments were equivalent, where equivalence was defined as a maximum difference of 7% between the two groups (p = 0.0005).

There were no significant differences in terms of safety between the 216 patients in the LMWH group and the 223 patients in the UFH group who received at least one injection of the randomized treatment. During the study period, 15 patients (3.4%) died (7 in the LMWH group and 8 in the UFH group): 2 sudden deaths, one in each group, including one case in which pulmonary embolism could not be excluded since no autopsy was performed, and 13 others deaths unrelated to the study treatments. Six patients (1.4%) presented a bleeding complication: 2 (0.9%) in the enoxaparin group (one major and one minor hemorrhage), and 4 (1.8%) in the UFH group (2 major and 2 minor hemorrhages).

These results indicate that subcutaneous enoxaparin 20 mg once daily for 10 days is as effective and well tolerated as subcutaneous UFH 5000 IU twice daily in the prevention of venous thromboembolic disease in bedridden elderly in-patients presenting an acute medical illness.
Serum Thrombopoietin (c-MpI Ligand) Levels in Patients with Liver Cirrhosis
Authors: Shimodaira Shigetaka , Ishida Fumihiro , Ichikawa Naoaki , Tahara Tomoyuki , Kato Takashi , Kodaira Hiroshi , Ito Toshiro , Tanaka Eiji , Sodeyama Takeshi , Kiyosawa Kendo , Kitano Kiyoshi
Published: July 2018

To clarify the role of c-Mpl ligand (thrombopoietin: TPO) in liver cirrhosis (LC), we examined serum TPO levels (sTPO) in patients with LG (N = 44), chronic hepatitis (CH; N = 13) and healthy controls (N = 41) by an enzyme-linked immunosorbent assay. Although platelet counts of all LC patients (89 ± 59 × 109/1; mean ± SD) were lower than those of controls and CH patients, sTPO levels in LC patients (1.23 ± 0.51 fmol/ml) were the same as those in controls (1.22 ± 0.37) and CH patients (1.18 ± 0.36). Platelet counts were significantly higher in splenectomized patients than in unsplenectomized patients, but the sTPO level did not differ between these two groups. In LC patients, the sTPO level was not correlated with the platelet count, but was correlated with prothrombin time, activated partial thromboplastin time, and total bilirubin, indicating that production of TPO in the liver decreases slightly with the development of liver dysfunction. Our findings suggest that production of TPO is maintained in LC patients and their thrombocytopenia is not due to a defect in platelet production.
Measurement of Glycoprotein llb/llla Blockade by Flow Cytometry with Fluorescein Isothiocyanate-conjugated Crotavirin, a Member of Disintegrins
Authors: Liu Chao-Zong , Hur Buo-Tsang , Huang Tur-Fu
Published: July 2018

The blockade of platelet membrane glycoprotein IIb/IIIa by a monoclonal antibody, 7E3, was measured by flow cytometry using a fluorescein isothiocyanate-conjugated disintegrin, FITC-crotavirin, as the probe. After treatment of platelets with 7E3 or 7E3 F(ab’)2, there is a good correlation between the inhibition of platelet aggregation and the blockade of FITC-crotavirin’s binding to platelets. The content of glycoprotein IIb/IIIa for the subsequent binding of FITC-crotavirin to the 7E3-pretreated platelets highly correlated to the extent of glycoprotein Ilb/IIIa, remaining available. It was evidenced by the observation that the sum of glycoprotein Ilb/IIIa occupation by 7E3 and that of FITC-crotavirin approached the total amount of glycoprotein Ilb/IIIa expressed on the platelet membrane. This indicates that the percentage inhibition of FITC-crotavirin’s binding at the saturation dose reflects the extent of glycoprotein Ilb/IIIa blockade by 7E3. At the saturation binding concentration (5 |xg/ml), FITC-crotavirin did not displace platelet bound 7E3. Gating the light-scattering profile for platelets, the binding of FITC-crotavirin to platelet glycoprotein Ilb/IIIa could be easily determined in diluted whole blood by direct stain method. The available unoccupied glycoprotein Ilb/IIIa of platelets in the 7E3 or 7E3 F(ab’)2-pretreated whole blood were measured by flow cytometry at the saturation binding dose of FITC-crotavirin (4 fig/ml) and the data showed that the higher deconcentration of antibody added into whole blood, the lower debinding of FITC-crotavirin to platelets. This technique may provide an alternative rapid method for measuring the blockade of glycoprotein Ilb/IIIa by 7E3, a promising anti-thrombotic agent, thus providing a monitoring method for adjusting the therapeutic dose of 7E3 or its related derivatives.
Human Umbilical Vein Smooth Muscle Cells as a Model to Study Thrombin Generation and Function: Effect of Thrombin Inhibitors
Authors: Catalioto Rose-Marie , Cucchi Paola , Renzetti Anna Rita , Criscuoli Marco , Subissi Alessandro
Published: July 2018

The aim of the present work was to study how human umbilical vein smooth muscle cells (HUVSMC) can initiate the coagulation process and to investigate the responses of these cells to thrombin. Exposure of HUVSMC to recalcified human plasma led to a time-dependent production of thrombin, measured both as amidolytic activity and as release of fibrinopeptide A. Thrombin activity was dose-dependently reduced by an anti-human tissue factor antibody (76 ± 3% at 10 Μg/ml) and by inhibitors like heparin, rec-hirudin, hirulog-1, Napap and hiru-norm, a novel hirudin-like thrombin inhibitor (IC50 = 2 ± 0.4, 8 ± 1, 130 ± 22, 199 ± 29 and 68 ± 8nM, respectively). The release of fibrinopeptide A was similarly prevented (IC50 = 14 ± 1,132 ± 25 and 50 ± 8 nM for rec-hirudin, Napap and hirunorm, respectively). Exogenously added thrombin increased thymidine incorporation into HUVSMC to 240 ± 30% of basal (EC50 = 0.49 ± 0.09 nM) and thrombin inhibitors blocked this effect (IC50 = 10 ± 3, 37 ± 17, 343 ± 165 and 1402 ± 758 nM for rec-hirudin, hirunorm, Napap and hirulog-1, respectively). Also recalcified human plasma was mitogenic for HUVSMC and its effect was mainly due to endogenously generated thrombin, as shown by the use of thrombin inhibitors. In conclusion, HUVSMC are capable of initiating the extrinsic coagulation cascade, leading to the formation of thrombin which promotes clotting and stimulates DNA synthesis. Thrombin inhibitors prevent both coagula-tive and cellular effects of thrombin.
Qualitative Platelet 12-Lipoxygenase Abnormality in a Patient with Essential Thrombocythemia
Authors: Tomo Kenjiro , Takayama Hiroshi , Kaneko Yoshiyuki , Fujita Jun , Nakamura Michihiro , Ueda Natsuo , Yamamoto Shozo , Okuma Minoru
Published: July 2018

Quantitative platelet 12-lipoxygenase (12-LOX) deficiency has been reported in some patients with myeloproliferative disorders (MPD). We report here for the first time a novel qualitative abnormality of the 12-LOX enzyme of platelets from a patient with essential thrombocythemia. The anti-12-LOX immunoprecipitates from the patient’s platelet homogenates showed a deficiency of 12-LOX activity, but contained normal amount of 12-LOX protein. There was no difference in subcellular localization of the enzyme between the patient’s platelets and normal ones. This 12-LOX protein lacking its enzyme activity showed slightly larger electrophoretic mobility than normal one, suggesting a molecular abnormality of the enzyme. However, we could not detect any genetic mutation causing such abnormalities in all exons of 12-LOX gene by sequencing the patient’s PCR-amplified DNA. Thus, our results indicate that the deficient activity of this abnormal 12-LOX protein is probably due to a posttranslational modification, and the possibility that platelets of some MPD patients have qualitative abnormality of the 12-LOX enzyme besides quantitative one.
Extrinsic permittivity in domain engineered rhombohedral BaTiO3 monocrystal
Authors: Bednyakov P. , Savinov M. , Pokorný J. , Hlinka J.
Published: July 2018

Arrangement of 90-degree domain walls in the domain structure of the ⟨111⟩pc-oriented single crystal plates of BaTiO3 was intentionally modified by combinations of in-plane and out-of-plane steady state electric poling at ambient temperature. It is shown that the annealed, in-plane, and out-of-plane poled samples exhibit markedly different dielectric properties at low temperatures. The difference in low-temperature permittivity behavior is enhanced by the out-of-plane fast-decayed bipolar electric pulse treatment, but the efficiency of this enhancement is strongly dependent on the initial domain structure. The absence of a clear signature of the pulse treatment in optical observations of the domain structure suggests that it might involve mostly changes in the 180-degree domain wall subsystem.
Simultaneous stress and mass change measurements arising from laser induced detuning of a quartz crystal microbalance
Authors: Goodman L. H. , Bililign E. S. , Keller B. W. , Kenny S. G. , Krim J.
Published: July 2018

We report a study of the frequency response of AT and BT cut Quartz Crystal Microbalances (QCMs) to laser illumination. AT and BT cut QCMs have a similar response to mass adsorption but the opposite frequency response to stress levels, allowing the individual contributions to stress and mass desorption induced by the laser light to be quantitatively investigated. A detailed analysis of the transient thermal behaviors in the quartz crystals has also been performed, which yields stress levels that are consistent with the observed results. Our results quantitatively confirm previous suggestions that radial compressive stress is a dominant contributor to the response of the QCM to laser illumination. They also establish a theoretical framework for the analysis of the transient phenomenon to infer temperature shifts and radial stress levels in the system irrespective of whether both AT and BT cut crystals are utilized.
Identifying avian indicators of elevation in the Gondwanan rainforests of Australia
Authors: Leach Elliot C. , Burwell Chris J. , Jones Darryl N. , Kitching Roger L.
Published: July 2018

Many montane avian communities are likely to be impacted negatively by future climate change. The ability to monitor these ecosystems effectively is therefore a priority. As species are expected to track their preferred climates by moving upwards in elevation, using indicator species of elevations has been suggested as a climate change monitoring strategy and has been explored for a variety of taxa in eastern Australia. Birds have great potential as vertebrate indicators due to their familiarity, detectability, and well known life histories. We used automated recording units (ARUs) and point counts to sample the avifauna along two elevational gradients in subtropical rainforest in north-eastern New South Wales, Australia. We used the indicator value protocol to identify avian indicators of elevation suitable for long-term monitoring. Pairs of species were more reliable than single species as indicators, and searching for indicators of elevational ranges (e.g. 300–500m) proved more effective than looking for indicators of single elevations (e.g. 300m). Point counts and ARUs were equally effective at determining indicators of elevations and ARUs performed particularly well in spring. We present avian indicator sets of lowland and highland sites, which provide a baseline for future monitoring of the effects of climate change on the region’s avifauna. The methodology employed here is broadly suitable for similar studies elsewhere. We propose that the use of ARUs to identify indicator species of elevations is an effective strategy for monitoring the effects of climate change on montane avian communities worldwide.
Upper Eyelid Blepharoplasty: A Novel Method to Predict and Improve Outcomes
Authors: Barmettler Anne , Wang Jessie , Heo Moonseong , Gladstone Geoffrey J
Published: July 2018

Background

In some upper eyelid blepharoplasties, maximal skin removal may not result in desired outcomes; raising crease height can therefore be considered. Currently, there is no method to determine the amount of skin to be excised and/or crease elevation required to achieve a specific outcome.

Objective

This study extrapolated an equation to determine amount of skin excision and/or lid crease elevation needed to achieve a specific eyelid margin to fold distance (MFD).

Methods

This institutional review board-approved, HIPAA-compliant study was a prospective, nonrandomized clinical trial. Patients were included if aged 30 to 100 years old and underwent upper eyelid blepharoplasty with one surgeon between 2012 and 2014. Exclusion criteria were thyroid eye disease, myasthenia gravis, myotonic dystrophy, pregnancy, blepharoptosis, prior eyelid surgery or trauma, concurrent brow surgery, and topical alpha-agonists. The following data were collected preoperatively and at postoperative months 1 and 6: age, gender, BMI, brow position, MFD, margin to crease distance (distance between eyelid margin and crease, MCD), and vertical skin distance (distance between eyelid margin and brow, VSD).

Results

A total 322 eyelids of 164 patients underwent 208 skin excisions, 26 crease elevations, and 88 combined skin excision and crease elevation. Age, gender, and BMI category were all nonsignificant and excluded from the final model. This equation was extrapolated with regression analysis: Change in MFD = −0.40 + (−0.28 × Change VSD) + (0.53 × Change MCD) with |R| = 0.28.

Conclusion

To better predict and obtain desired upper eyelid blepharoplasty outcomes, the authors created an equation.

Level of Evidence: 4
Transcriptomic analysis of longitudinal Burkholderia pseudomallei infecting the cystic fibrosis lung
Authors: Price Erin P. , Viberg Linda T. , Kidd Timothy J. , Bell Scott C. , Currie Bart J. , Sarovich Derek S.
Published: July 2018

The melioidosis bacterium, Burkholderia pseudomallei, is increasingly being recognised as a pathogen in patients with cystic fibrosis (CF). We have recently catalogued genome-wide variation of paired, isogenic B. pseudomallei isolates from seven Australasian CF cases, which were collected between 4 and 55 months apart. Here, we extend this investigation by documenting the transcriptomic changes in B. pseudomallei in five cases. Following growth in an artificial CF sputum medium, four of the five paired isolates exhibited significant differential gene expression (DE) that affected between 32 and 792 genes. The greatest number of DE events was observed between the strains from patient CF9, consistent with the hypermutator status of the latter strain, which is deficient in the DNA mismatch repair protein MutS. Two patient isolates harboured duplications that concomitantly increased expression of the β-lactamase-encoding gene penA, and a 35 kb deletion in another abolished expression of 29 genes. Convergent expression profiles in the chronically-adapted isolates identified two significantly downregulated and 17 significantly upregulated loci, including the resistance-nodulation-division (RND) efflux pump BpeEF–OprC, the quorum-sensing hhqABCDE operon, and a cyanide- and pyocyanin-insensitive cytochrome bd quinol oxidase. These convergent pathoadaptations lead to increased expression of pathways that may suppress competing bacterial and fungal pathogens, and that enhance survival in oxygen-restricted environments, the latter of which may render conventional antibiotics less effective in vivo. Treating chronically adapted B. pseudomallei infections with antibiotics designed to target anaerobic infections, such as the nitroimidazole class of antibiotics, may significantly improve pathogen eradication attempts by exploiting this Achilles heel.
Defining the genetic control of human blood plasma N-glycome using genome-wide association study
Authors: Sharapov Sodbo Zh. , Tsepilov Yakov A. , Klaric Lucija , Mangino Massimo , Thareja Gaurav , Simurina Mirna , Dagostino Concetta , Dmitrieva Julia , Vilaj Marija , Vuckovic Frano , Pavic Tamara , Stambuk Jerko , Trbojevic-Akmacic Irena , Kristic Jasminka , Simunovic Jelena , Momcilovic Ana , Campbell Harry , Dunlop Malcolm , Farrington Susan , Pucic-Bakovic Maja , Gieger Christian , Allegri Massimo , Louis Edouard , Georges Michel , Suhre Karsten , Spector Tim , Williams Frances MK , Lauc Gordan , Aulchenko Yurii
Published: July 2018

Glycosylation is a common post-translational modification of proteins. It is known, that glycans are directly involved in the pathophysiology of every major disease. Defining genetic factors altering glycosylation may provide a basis for novel approaches to diagnostic and pharmaceutical applications. Here, we report a genome-wide association study of the human blood plasma N-glycome composition in up to 3811 people. We discovered and replicated twelve loci. This allowed us to demonstrate a clear overlap in genetic control between total plasma and IgG glycosylation. Majority of loci contained genes that encode enzymes directly involved in glycosylation (FUT3/FUT6, FUT8, B3GAT1, ST6GAL1, B4GALT1, ST3GAL4, MGAT3, and MGAT5). We, however, also found loci that are likely to reflect other, more complex, aspects of plasma glycosylation process. Functional genomic annotation suggested the role of DERL3, which potentially highlights the role of glycoprotein degradation pathway, and such transcription factor as IKZF1.
Protection of rhesus macaques against vaginal SHIV challenges by VRC01 and an anti-α4β7antibody
Authors: Calenda Giulia , Frank Ines , Arrode-Brusés Géraldine , Pegu Amarendra , Wang Keyun , Arthos James , Cicala Claudia , Grasperge Brooke , Blanchard James L. , Maldonado Stephanie , Roberts Kevin , Gettie Agegnehu , Fauci Anthony S. , Mascola John R. , Martinelli Elena
Published: July 2018

VRC01 protects macaques from vaginal SHIV infection after a single high-dose challenge. Infusion of a simianized anti-α4β7mAb (Rh-α4β7) just prior to, and during repeated vaginal exposures to SIVmac251 partially protected macaques from vaginal SIV infection and rescued CD4+T cells. To investigate the impact of combining VRC01 and Rh-α4β7on SHIV infection, 3 groups of macaques were treated with a suboptimal dosing of VRC01 alone or in combination with Rh-α4β7or with control antibodies prior to the initiation of weekly vaginal exposures to a high dose (1000TCID50) of SHIVAD8-EO.The combination Rh-α4β7-VRC01 significantly delayed SHIVAD8-EOvaginal infection. Following infection, VRC01-Rh-α4β7-treated macaques maintained higher CD4+T cell counts and exhibited lower rectal SIV-DNA loads compared to the controls. Interestingly, VRC01-Rh-α4β7-treated macaques had less IL-17 producing cells in the blood and the gut during the acute phase of infection. Moreover, higher T cell responses to the V2-loop of the SHIVAD8-EOenvelope in the VRC01-Rh-α4β7group inversely correlated with set point viremia. The combination of suboptimal amounts of VRC01 and Rh-α4β7delayed infection, altered anti-viral immune responses and minimized CD4+T cell loss. Further exploration of the effect of combining bNAbs with Rh-α4β7on SIV/HIV infection and anti-viral immune responses is warranted and may lead to novel preventive and therapeutic strategies.

Short summary

A combination of VRC01 and Rh-α4β7significantly delayed SHIV acquisition, protected CD4 counts, decreased gut viral load and modified the immune response to the virus.
What is a cognitive map? Organising knowledge for flexible behaviour
Authors: Behrens Timothy E.J. , Muller Timothy H. , Whittington James C.R. , Mark Shirley , Baram Alon B. , Stachenfeld Kimberley L. , Kurth-Nelson Zeb
Published: July 2018

It is proposed that a cognitive map encoding the relationships between entities in the world supports flexible behaviour, but the majority of the neural evidence for such a system comes from studies of spatial navigation. Recent work describing neuronal parallels between spatial and non-spatial behaviours has rekindled the notion of a systematic organisation of knowledge across multiple domains. We review experimental evidence and theoretical frameworks that point to principles unifying these apparently disparate functions. These principles describe how to learn and use abstract, generalisable knowledge and suggest map-like representations observed in a spatial context may be an instance of general coding mechanisms capable of organising knowledge of all kinds. We highlight how artificial agents endowed with such principles exhibit flexible behaviour and learn map-like representations observed in the brain. Finally, we speculate on how these principles may offer insight into the extreme generalisations, abstractions and inferences that characterise human cognition.
Deep Semantic Protein Representation for Annotation, Discovery, and Engineering
Authors: Schwartz Ariel S , Hannum Gregory J , Dwiel Zach R , Smoot Michael E , Grant Ana R , Knight Jason M , Becker Scott A , Eads Jonathan R , LaFave Matthew C , Eavani Harini , Liu Yinyin , Bansal Arjun K , Richardson Toby H
Published: July 2018

Computational assignment of function to proteins with no known homologs is still an unsolved problem. We have created a novel, function-based approach to protein annotation and discovery called D-SPACE (Deep Semantic Protein Annotation Classification and Exploration), comprised of a multi-task, multi-label deep neural network trained on over 70 million proteins. Distinct from homology and motif-based methods, D-SPACE encodes proteins in high-dimensional representations (embeddings), allowing the accurate assignment of over 180,000 labels for 13 distinct tasks. The embedding representation enables fast searches for functionally related proteins, including homologs undetectable by traditional approaches. D-SPACE annotates all 109 million proteins in UniProt in under 35 hours on a single computer and searches the entirety of these in seconds. D-SPACE further quantifies the relative functional effect of mutations, facilitating rapid in silico mutagenesis for protein engineering applications. D-SPACE incorporates protein annotation, search, and other exploratory efforts into a single cohesive model.