bluuebunny/crossref_metadata_2025_split huggingface dataset:
Local delivery of 17β-estradiol improves reendothelialization and decreases inflammation after coronary stenting in a porcine model
Authors: Chandrasekar Baskaran , Sirois Martin , Geoffroy Pascale , Lauzier Dominique , Nattel Stanley , Tanguay Jean-François 
Published: October 2005

SummaryIn the current study, we investigated the effect of local intravascular delivery of 17β-estradiol (17β-E) on subsequent instent neointimal hyperplasia. Twenty-seven stents were implanted in coronary arteries of juvenile swine. Coronary arteries were randomized to local treatment with 17β-E or no drug therapy (control-vehicle treated). Twenty-eight days posttreatment, angiographic images revealed an improved minimal lumen diameter (2.2 ± 0.2 vs. 1.3 ± 0.2 mm, P < 0.005) and a reduction of late lumen loss (1.7 ± 0.2 vs. 2.3 ± 0.1 mm, P < 0.01) in 17β-E-treated vessels compared to control-vehicle treated. Histological analyses showed a reduction of stenosis (51.49 ± 6.75 vs.70.86 ± 6.24%, P < 0.05), mean neointimal thickness (0.51 ± 0.07 vs.0.83 ± 0.14 mm, P < 0.05) and inflammation score (1.29 ± 0.28 vs. 2.85 ± 0.40, P < 0.05) in 17β-E-treated arteries compared to control-vehicle treated arteries. Immunohistochemistry analyses revealed a reduction of proliferating smooth muscle cells and increased in-stent reendothelialization in 17β-E-treated arteries. Finally, we observed a correlation between neointimal hyperplasia and inflammation score, which in turn, was inversely related to reendothelialization. Locally delivered, 17β-E is inhibiting the inflammatory response and smooth muscle cells proliferation and improving vascular reendothelialization which together are contributing to reduce instent restenosis in a porcine coronary injury model. Together, these data demonstrate the potential clinical application of 17β-estradiol to improve vascular healing and prevent in-stent restenosis.
Differential gene expression in activated monocyte-derived macrophages following binding of factor VIIa to tissue factor
Authors: Muth Heidrun , Kreis Ingo , Zimmermann Rene , Tillmanns Harald , Hölschermann Hans 
Published: October 2005

SummaryFactor VIIa/tissue factor (FVIIa/TF) interaction has been reported to induce intracellular signalling in cells constitutively expressing TF, independently of downstream activation of the coagulation cascade. It is unknown, however, whether binding of FVII to its cofactor TF alters the gene expression profile in cells which inducible express TF under inflammatory conditions. To address this issue, gene expression patterns in cultured LPSstimulated monocyte-derived macrophages with or without exposure to FVIIa were compared by cDNA macro-array analysis. Of the 1176 genes examined on the array, a small set of six genes (IL-6, IL-8, TNF-a, GRO-beta alpha-thymosin, cathepsin H) were consistently up-regulated and one gene suppressed (alpha-antitrypsin) in response to FVIIa in activated monocyte-derived macrophages. Among the seven genes identified by array analysis, five genes were finally confirmed by real-time RT-PCR. Interestingly, all of these genes differentially regulated in response to FVIIa (GRO-beta, IL-6, IL-8, TNF-α and alpha-antitrypsin) are critical in inflammation. The changes in gene expression were reflected by corresponding changes in the protein concentrations of IL-6 and IL-8 as demonstrated by ELISA. Active site-inhibited FVIIa had no effect on gene expression indicating that FVIIa-induced gene alteration is dependent on the proteolytic activity of FVIIa. The FVIIa-induced alterations in gene expression were found to be TF-dependent but independent of downstream coagulation proteins like thrombin and FXa. In summary, this study demonstrates that binding of FVIIa to its cofactor TF enhances restricted pro-inflammatory genes in activated monocyte-derived macrophages. By up-regulation of chemokines critical for leukocyte recruitment, FVIIa/TF interaction on activated monocyte- derived macrophages could be relevant to prepare monocytes/ macrophages for extravasation and may represent a novel amplification loop of leukocyte recruitment.
Expressed isolated integrin β1 subunit cytodomain induces endothelial cell death secondary to detachment
Authors: Alghisi Gian , Bamat Jeannine , Ponsonnet Lionel , Bieler Grégory , Bonnard Claude , Hasmim Meriem , Vassalli Giuseppe , Paroz Cécile , Oguey Delphine , Rüegg Curzio 
Published: October 2005

SummaryExpression of isolated β integrin cytoplasmic domains in cultured endothelial cells was reported to induce cell detachment and death. To test whether cell death was the cause or the consequence of cell detachment, we expressed isolated integrin β1 cytoplasmic and transmembrane domains (CH1) in cultured human umbilical vein endothelial cells (HUVEC), and monitored detachment, viability, caspase activation and signaling. CH1 expression induced dose-dependent cell detachment. At 24 h over 90% of CH1-expressing HUVEC were detached but largely viable (>85%). No evidence of pro-caspase-8, –3, and PARP cleavage or suppression of phosphorylation of ERK, PKB and Iκ-B was observed. The caspase inhibitor z-VAD did not prevent cell detachment. At 48 h, however, CH1-expressing cells were over 50% dead. As a comparison trypsin-mediated detachment resulted in a time-dependent cell death, paralleled by caspase-3 activation and suppression of ERK, PKB and Iκ-B phosphoyrylation at 24 h or later after detachment. HUVEC stimulation with agents that strengthen integrin-mediated adhesion (i.e.PMA, the Src inhibitor PP2 and COMP-Ang1) did not prevent CH1-induced detachment. Expression of CH1 in rat carotid artery endothelial cells in vivo caused endothelial cell detachment and increased nuclear DNA fragmentation among detached cells. A construct lacking the integrin cytoplasmic domain (CH2) had no effect on adhesion and cell viability in vitro and in vivo. These results demonstrate that isolated β1 cytoplasmic domain expression induces caspase-independent detachment of viable endothelial cells and that death is secondary to detachment (i.e. anoikis). They also reveal an essential role for integrins in the adhesion and survival of quiescent endothelial cells in vivo.
Shiga toxin 2 and lipopolysaccharide cause monocytic THP-1 cells to release factors which activate platelet function
Authors: Guessous Fadila , Polanowska-Grabowska Renata , Keepers Tiffany , Obrig Tom , Gear Adrian , Marcinkiewicz Marek 
Published: October 2005

SummaryPlatelet and monocyte activation may contribute to hemolytic anemia, thrombocytopenia and renal failure associated with the hemolytic uremic syndrome (HUS) caused by Escherichia coli O157:H7. Since Shiga toxins (Stxs) and lipopolysaccharide (LPS) from this bacterium are implicated in the pathogenesis of HUS, we examined whether stimulation of THP-1 human monocytic cells by Shiga toxin 2 (Stx2) and LPS can lead to the activation of platelet function. We now show that Stx2 caused THP-1 cells to release the chemokines IL-8, MDC, and RANTES and that the presence of LPS further stimulated this release. IL-8 was produced in greatest amount and was an effective co-agonist for inducing platelet aggregation. Primary human monocytes also released large amounts of IL-8 in response to LPS and Stx2. Factors released by THP-1 cells exposed to Stx2 and LPS activated platelet function as evidenced by increased aggregation, serotonin secretion, P-selectin exposure and by the formation of stable platelet-monocyte aggregates. Our data therefore show that monocytes exposed to E. coli-derived Stx2 and LPS release factors which activate platelet function.
Understanding platelets
Authors: Dittrich Marcus , Birschmann Ingvild , Stuhlfelder Christiane , Sickmann Albert , Herterich Sabine , Nieswandt Bernhard , Walter Ulrich , Dandekar Thomas 
Published: October 2005

SummaryNew large-scale analysis techniques such as bioinformatics, mass spectrometry and SAGE data analysis will allow a new framework for understanding platelets. This review analyses some important options and tasks for these tools and examines an outline of the new, refined picture of the platelet outlined by these new techniques. Looking at the platelet-specific building blocks of genome, (active) transcriptome and proteome (notably secretome and phospho-proteome), we summarize current bioinformatical and biochemical approaches, tasks as well as their limitations. Understanding the surprisingly complex platelet regarding compartmentalization, key cascades, and pathways including clinical implications will remain an exciting and hopefully fruitful challenge for the future.
Biphasic effects of angiotensin II and receptor antagonism on aggregability and protein kinase C phosphorylation in human platelets
Authors: Kizawa Hideki , Nagane Yuriko , Kondoh Ryushi , Iwa Yoko , Akutsu Hitomi , Tohgi Hideo , Terayama Yasuo , Utsugisawa Kimiaki 
Published: October 2005

SummaryIn order to define the role of angiotensin II (AngII) receptor subtypes, AT1 and AT2, in platelet activation, we examined the effects of AngII and receptor antagonists on both aggregability and phosphorylation status of protein kinase C (PKC) isoforms in human platelets obtained from 56 healthy volunteers. AngII promoted both spontaneous and agonist (collagen and ADP) stimulated platelet aggregation at concentrations of 10 nM or less, but the promotion effects were lost at 100 nM. Antagonism of AT1 receptor inhibited the promotion effects of AngII at 10 nM or less. On the other hand, antagonism of AT2 receptor enhanced platelet aggregability modestly with AngII at 10 nM or less, and markedly with 100 nM AngII. Furthermore, with 10 nM AngII, phospho-PKCα/βII expression in platelets was increased after collagen stimulation and was inhibited by antagonism of AT1 receptor. With 100 nM AngII, expression levels of phospho-PKCα/ βII remained low even after collagen stimulation but were markedly enhanced by antagonism of AT2 receptor. These findings suggest that at 10 nM or below, AngII promotes aggregability and PKC phosphorylation in human platelets through the AT1 receptor, which can be inhibited by AT1 receptor antagonists, but at higher concentrations, the promotion effects were lost through the opposing action of the AT2 receptor. The present study may provide an additional mechanism for AT1 receptor antagonism, which would provide clinical benefit to patients with stroke or cardiovascular disease accompanied by hypertension.
Differences in the clinically effective molar concentrations of four direct thrombin inhibitors explain their variable prothrombin time prolongation
Authors: Greinacher Andreas , Craven Sharon , Dewar Lori , Sheppard Jo-Ann , Ofosu Frederick , Warkentin Theodore 
Published: October 2005

SummaryFour direct thrombin inhibitors (DTIs), lepirudin, bivalirudin, argatroban, and melagatran, differ in their ability to prolong the prothrombin time (PT). Paradoxically, the DTI in clinical use with the lowest affinity for thrombin (argatroban) causes the greatest PT prolongation. We compared the effects of these DTIs on various clotting assays and on inhibition of human and bovine factor Xa (FXa). On a mole-for-mole basis, lepirudin was most able to prolong the PT, activated partial thromboplastin time (APTT), and thrombin clotting time (TCT), whereas argatroban had the least effect. At concentrations that doubled the APTT (argatroban, 1 μmol/l; melagatran, 0.5 μmol/l; bivalirudin, 0.25 μmol/l; lepirudin, 0.06 μmol/l), the rank order for PT prolongation was: argatroban > melagatran > bivalirudin > lepirudin. Although the Ki’s associated with inhibition of human FXa by melagatran (1.4 μmol/l) and argatroban (3.2 μmol/l) approach their therapeutic concentrations, inhibition of FXa did not appear to be a major contributor to PT prolongation, since argatroban also prolonged the PT of bovine plasma (despite a Ki for bovine FXa of 2,600 μmol/l). Only melagatran inhibited prothrombinase-bound FXa. We conclude that the differing effects of the DTIs on PT prolongation are primarily driven by their respective molar plasma concentrations required for clinical effect. DTIs with a relatively low affinity for thrombin require high plasma concentrations to double the APTT; these higher plasma concentrations, in turn, quench more of the thrombin generated in the PT, thereby more greatly prolonging the PT.
Pravastatin reduces thrombogenicity by mechanisms beyond plasma cholesterol lowering
Authors: Casani Laura , Sanchez-Gomez Sonia , Vilahur Gemma , Badimon Lina 
Published: October 2005

SummaryInhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase are widely used in the management and prevention of cardiovascular disease. In addition to its major activity, plasma lipid lowering, statins have shown a wide spectrum of additional effects that may contribute to their benefits in the prevention of cardiovascular disease. Our objective was to study whether treatment with a statin, pravastatin, could reduce thrombosis triggered by damaged vessels without changing plasma cholesterol levels. A cholesterol-clamp animal model was developed by feeding swine for 100 days on an hypercholesterolemic (HL) diet; in the last 50 days, they were randomly assigned to receive either placebo (HLC) or pravastatin (5mg . kg−1. day−1) (HLP) in addition to the hypercholesterolemic diet. A normocholesterolemic control group (NLC) was simultaneously studied. There were no significant differences in total cholesterol, LDL and HDL plasma levels between the two groups; however, mural thrombosis triggered by both an eroded and disrupted vessel wall was significantly inhibited by pravastatin (P<0.05). Axial dependence analysis of platelet deposition revealed that pravastatin treatment reduced the increase in platelet deposition associated to the shear rate increase at the stenosis. Additionally, pravastatin treatment significantly reduced platelet membrane RhoA expression (P <0.05) and vascular wall tissue factor (TF) protein expression (P <0.05). In addition to its lipid lowering effects, pravastatin can reduce blood thrombogenicity by mechanisms independent of plasma cholesterol lowering.
Combinatorial peptides directed to inhibitory antibodies against human blood clotting factor VIII
Authors: Kopecky Eva-Maria , Greinstetter Sabine , Pabinger Ingrid , Buchacher Andrea , Römisch Jürgen , Jungbauer Alois 
Published: October 2005

SummaryThe development of antibodies against blood clotting factorVIII is a major complication affecting 20–30% of hemophilia A patients receiving replacement with FVIII concentrates. This study investigated generating peptides acting as broadly neutralizing agents to block factor VIII antibodies. These peptides were selected from dual positional scanning decapeptide libraries on cellulose membranes. From this library comprising 6.8×1012 peptides we selected 468 peptides for further screening rounds. Finally we identified two decapeptides with the ability to block 8 out of 10 inhibitory antibodies from sera of patients with FVIII inhibitors demonstrated by competition assays. Sequence alignment of the peptides showed similarity with several domains in the FVIII molecule demonstrating the mimotope nature of the selected peptides. Our results show the efficiency of the combinatorial library approach and show the potential of combinatorial peptides to compete out polyclonal inhibitor IgG from a broad range of patients’ sera. Combinatorial peptides could be novel and highly effective drug candidates for alternative treatment in patients with factor VIII inhibitors.
Protein C Sapporo (protein C Glu 25 → Lys): A heterozygous missense mutation in the Gla domain provides new insight into the interaction between protein C and endothelial protein C
receptor
Authors: Nakabayashi Toru , Mizukami Kazuhiro , Naitoh Sumiyoshi , Takeda Mika , Shikamoto Yasuo , Nakagawa Takafumi , Kaneko Hiroki , Tarumi Takashi , Mizoguchi Itaru , Mizuno Hiroshi , Koike Takao , Ieko Masahiro 
Published: October 2005

SummaryInteraction of the γ-carboxyglutamic acid (Gla) domain of protein C with endothelial protein C receptor (EPCR) is a critical step for efficient activation of protein C, though interactions by mutants in the Gla domain of protein C with EPCR have been rarely evaluated. We identified a 44-year-old Japanese woman with a history of recurrent thromboembolism as an inherited missense mutation, the first such case reported in Japan, which involved a protein C Gla 25 mutation. Total protein C antigen and Gla protein C antigen levels in the proband were normal. Protein C activity measured with an anticoagulant assay was reduced, whereas that measured with an amidolytic assay was normal. She was therefore phenotypically diagnosed as type IIb protein C deficiency. Direct sequencing of the PCR fragments revealed a heterozygous G toA transition at nucleotide position 1462 in exon 3, which predicted an amino acid substitution of Glu 25 by Lys. Her mother and one son were also heterozygous for this mutation. A molecular dynamics simulation of Gla 25→Lys/EPCR complex in water suggested that the affinity between the molecules was decreased compared to the wild type Gla domain/EPCR complex. Since Gla 25 has been shown to play an important role in protein C function, not only in membrane phospholipid binding but also in binding to EPCR, our findings provide new insight into the mechanism by which the Glu 25→Lys mutation induces type IIb protein C deficiency in individuals.
Modulation of the intestinal response to ionizing radiation by anticoagulant and non-anticoagulant heparins
Authors: Wang Junru , Zheng Huaien , Qiu Xiaohua , Kulkarni Ashwini , M. Fink Louis , Hauer-Jensen Martin 
Published: October 2005

SummaryEndothelial dysfunction is involved in radiation responses in many normal tissues, including intestine. Endothelium-directed interventions ameliorate intestinal radiation injury (radiation enteropathy) in animal models, and anecdotal reports also suggest a beneficial effect of heparin. This study assessed low molecular weight heparin as an intestinal radiation response modifier. Rats underwent localized small bowel irradiation. Groups of rats were treated with saline, nadroparin (3 mg/kg/d), or a nonanticoagulant heparin (SR80258, 3 mg/kg/d), from 3 days before to 2 weeks after irradiation. The intestinal radiation response was assessed 2 weeks and 6 weeks after irradiation using quantitative histology; morphometry, and cellular and molecular endpoints. Compared to vehicle-treated controls, nadroparin sig-nificantly exacerbated structural radiation injury, neutrophil infiltration, and TGFβ and collagen I immunoreactivity levels 2 weeks after irradiation. SR80258 was associated with increased TGFβ levels, but the other parameters did not reach statistical significance. At 6 weeks, structural, cellular, and molecular injury was similar in the three experimental groups. Heparin, in contrast to antiplatelet agents and direct thrombin inhibitors, does not ameliorate, but exacerbates acute intestinal radiation toxicity. These data underscore the importance of heparin as an inhibitor of physiological anti-inflammatory mechanisms during tissue injury, as well as the non-anticoagulant effects of heparin. Moreover, these data may have implications for the use of heparin during radiation therapy.
Multiplex fluorescent analysis of four short tandem repeats for rapid haemophilia A molecular diagnosis
Authors: Sánchez-García Jorge , Gallardo Dominique , Ramírez Lorena , Vidal Francisco 
Published: October 2005

SummaryIndirect molecular diagnosis of hemophilia A (HA) is carried out by analyzing intragenic polymorphic markers described along the coagulation factorVIII (FVIII) gene. Several studies have demonstrated that the two commonly used intronic short tandem repeats (STR13 and STR22) located in the FVIII gene are highly informative for this task. Two extragenic markers closely linked to FVIII (DXS1073 and DXS1108) have also been described as valuable tools for gene tracking. The objective of the present work was to develop a rapid, single-tube automated method to simultaneously analyze these four STRs. Consistent amplification was achieved by quadruplex fluorescent PCR and the products were analyzed by capillary electrophoresis. Validation of the method included DNA analysis of 88 individuals from a control population, 45 HA patients and 32 individuals from 10 HA-affected families. Statistical study showed that the STR13, STR22 and DXS1108 loci were in significant linkage disequilibrium, whereas DXS1073 was not. Nevertheless, the combination of the four markers offered a high heterozygosity rate (>90%) that improved tracing of FVIII gene inheritance. Optimal results with application to single cells in a HA preimplantation genetic diagnosis (PGD) protocol demonstrated the sensitivity of the technique. In conclusion, the automated fluorescent method described is an extremely rapid, simple and highly informative one that is easy to standardize and allows direct comparison of results among different groups working with genetic counseling, prenatal diagnosis and PGD in HA-affected families.
Complement C3 and C-reactive protein levels in patients with stable coronary artery disease
Authors: Ajjan Ramzi , Futers Timothy , Brown Jane , Cymbalista Charlotte , Boothby May , Carter Angela , Grant Peter 
Published: October 2005

SummaryThe aim of this study was to determine whether complement C3 is an indicator of coronary artery disease (CAD). We measured plasma C3 and CRP levels in 278 patients undergoing coronary angiography for typical symptoms of CAD and 269 healthy age and sex matched controls. C3 levels were significantly higher in patients compared with controls (1.15 g/l and 0.92 g/l respectively; p<0.001). In the patient group, C3 levels correlated with BMI, fasting glucose, HbA1c, fibrinogen, CRP and HDL in both men and women. CRP levels were also higher in patients compared with controls (1.14 mg/l and 0.86 mg/l respectively; p=0.005) and correlated with markers of the metabolic syndrome. In a logistic regression model including C3, smoking, hypertension, cholesterol and diabetes, C3 was independently associated with CAD with an odds ratio of 3.20 for a 1 SD increase in C3 levels. In contrast, CRP was not independently associated with CAD in a similar regression analysis. In conclusion, both C3 and CRP plasma levels are elevated in patients with symptoms of CAD. However, C3 seems to be a better indicator of CAD than CRP in this study, suggesting that C3 could be an additional marker for risk stratification in atherosclerosis.
Large deletions of the PROS1 gene in a large fraction of mutation-negative patients with protein S deficiency
Authors: Hillarp Andreas , Säll Torbjörn , Zöller Bengt , Dahlbäck Björn , Halldén Christer , Johansson Anna 
Published: October 2005

SummaryProtein S deficiency is an autosomal dominant disorder that results from mutations in the PROS1 gene. Conventional mutation detection techniques fail to detect a pathogenic PROS1 mutation in approximately 50% of cases. The present study investigates whether large deletions of PROS1 are found in families where mutations in the PROS1 gene have not been found despite sequencing. For this purpose, a dense set of SNP and microsatellite markers were used in segregation analysis to identify deletions. Large deletions were identified by this technique in three out of eight investigated families (38%). The deletions encompassed at least 35 kb, 437 kb and 449 kb respectively. The deletions were confirmed by quantitative PCR. Haplotype analysis showed that the three large deletions and the five other disease haplotypes were all different. All of the eight disease haplotypes co-segregated with protein S deficiency, but each of the five non-deletion haplotypes were present also in normal individuals. In conclusion: Large deletions of PROS1 are relatively common in protein S deficiency patients and screening for large deletions in PROS1 mutation-negative individuals are therefore warranted.