bluuebunny/crossref_metadata_2025 huggingface dataset:
Cdk2 Deficiency Decreases ras/CDK4-Dependent Malignant Progression, but Not myc-Induced Tumorigenesis
Authors: Macias Everardo , Kim Yongbaek , Miliani de Marval Paula L. , Klein-Szanto Andres , Rodriguez-Puebla Marcelo L.
Published: October 2007

We have previously shown that forced expression of CDK4 in mouse skin (K5CDK4 mice) results in increased susceptibility to squamous cell carcinoma (SCC) development in a chemical carcinogenesis protocol. This protocol induces skin papilloma development, causing a selection of cells bearing activating Ha-ras mutations. We have also shown that myc-induced epidermal proliferation and oral tumorigenesis (K5Myc mice) depends on CDK4 expression. Biochemical analysis of K5CDK4 and K5Myc epidermis as well as skin tumors showed that keratinocyte proliferation is mediated by CDK4 sequestration of p27Kip1 and p21Cip1, and activation of CDK2. Here, we studied the role of CDK2 in epithelial tumorigenesis. In normal skin, loss of CDK2 rescues CDK4-induced, but not myc-induced epidermal hyperproliferation. Ablation of CDK2 in K5CDK4 mice results in decreased incidences and multiplicity of skin tumors as well as malignant progression to SCC. Histopathologic analysis showed that K5CDK4 tumors are drastically more aggressive than K5CDK4/CDK2−/− tumors. On the other hand, we show that CDK2 is dispensable for myc-induced tumorigenesis. In contrast to our previous report of K5Myc/CDK4−/−, K5Myc/CDK2−/− mice developed oral tumors with the same frequency as K5Myc mice. Overall, we have established that ras-induced tumors are more susceptible to CDK2 ablation than myc-induced tumors, suggesting that the efficacy of targeting CDK2 in tumor development and malignant progression is dependent on the oncogenic pathway involved. [Cancer Res 2007;67(20):9713–20]
The Original Pathologische Anatomie Leiden-Endothelium Monoclonal Antibody Recognizes a Vascular Endothelial Growth Factor–Binding Site within Neuropilin-1
Authors: Jaalouk Diana E. , Ozawa Michael G. , Sun Jessica , Lahdenranta Johanna , Schlingemann Reinier O. , Pasqualini Renata , Arap Wadih
Published: October 2007

For two decades, the antigen recognized by the Pathologische Anatomie Leiden-Endothelium (PAL-E) monoclonal antibody, a standard vascular endothelial cell marker, has remained elusive. Here, we used a combinatorial phage display–based approach (“epitope mapping”) to select peptides binding to the original PAL-E antibody. We found that a subset of the selected panel of peptides had motifs with strong homology to an exposed site within the b1 domain of human neuropilin-1 (NRP-1). We confirmed peptide binding by ELISA and by surface plasmon resonance. We also showed that the PAL-E antigen colocalizes with NRP-1 staining in endothelial cells. Crystal structure of the b1 domain in NRP-1 suggests that the PAL-E binding site overlaps with a vascular endothelial growth factor (VEGF) binding site. Taken together, these results indicate that NRP-1 is an endothelial cell antigen recognized by the true PAL-E antibody. The consistent biochemical, morphologic, and functional features between the PAL-E antigen and NRP-1 support our interpretation. Given that NRP-1 is a VEGF receptor, these results explain the attributes of the PAL-E antibody as a marker of vascular permeability and angiogenesis. [Cancer Res 2007;67(20):9623–9]
Supporting the Systematic Assessment of Clinical Processes: the MedFlow Method
Authors: Chimiak-Opoka J. , Ammenwerth E. , Saboor S.
Published: October 2007

Objectives:
Healthcare is characterized by complex cooperation between highly specialized healthcare departments. This often leads to inefficient clinical processes. In orderto improve these processes, a systematic assessment method is needed. Such methods are still missing. The objective of this paper is to propose and evaluate a method to support the systematic and semi-automatic assessment of clinical processes, with special focus on the quality of information logistics.

Methods:
Criteria for the quality of information logistics were collected based on literature research and system analysis. Appropriate quality checks for these criteria were developed. An extended process modelling notation was developed. The method was evaluated in a pilot study.

Results:
An own model integrates four sub-models with each concentrating on distinct process aspects (i.e., control flow, data flow, tool usage, organizational information). In orderto assess the quality of a process, selected process details are combined in “views”. Weak points are then detected by applying specific rule-sets on these views. Each rule-set represents a pattern of critical cross-points which are searched for in the appropriate view-matrix. The MedFlow method was evaluated in a first pilot study in radiological departments – applying quality checks for the detection of e.g. media cracks or testing the transcription of information objects.

Conclusion:
The MedFlow method is best used to assess clinical processes regarding their control flow and information handling. The latter directly influences the quality of communication and thusthe quality of whole processes. However, this must be evaluated in further studies.
Large Histological Serial Sections for Computational Tissue Volume Reconstruction
Authors: Scherf N. , Einenkel J. , Horn L.-C. , Wentzensen N. , Loeffler M. , Kuska J.-P. , Braumann U.-D.
Published: October 2007

Objectives:
A proof of principle study was conducted for microscopic tissue volume reconstructions using a new image processing chain operating on alternately stained large histological serial sections.

Methods:
Digital histological images were obtained from conventional brightfield transmitted light microscopy. A powerful nonparametric nonlinear optical flow-based registration approach was used. In order to apply a simple but computationally feasible sum-of-squared-differences similarity measure even in case of differing histological stainings, a new consistent tissue segmentation procedure was placed upstream.

Results:
Two reconstructions from uterine cervix carcinoma specimen were accomplished, one alternately stained with p16INK4a (surrogate tumor marker) and H&E (routine reference), and another with three different alternate stainings, H&E, p16INK4a, and CD3 (a T-lymphocyte marker). For both cases, due to our segmentation-based reference-free nonlinear registration procedure, resulting tissue reconstructions exhibit utmost smooth image-to-image transitions without impairing warpings.

Conclusions:
Our combination of modern nonparametric nonlinear registration and consistent tissue segmentation has turned out to provide a superior tissue reconstruction quality.
Inhibition of microparticle release triggers endothelial cell apoptosis and detachment
Authors: Sturk Augueste , Hau Chi , Nieuwland Rienk , Abid Hussein Mohammed , Böing Anita
Published: October 2007

Endothelial cell cultures contain caspase 3-containing microparticles (EMP), which are reported to form during or after cell detachment. We hypothesize that also adherent endothelial cells release EMP, thus protecting these cells from caspase 3 accumulation, detachment and apoptosis. Human umbilical vein endothelial cells (HUVEC) were incubated with and without inhibitors of microparticle release (Y-27632,calpeptin), both in the absence or presence of additional “external stress”, i.e. the apoptotic agent staurosporin (200 nM) or the activating cytokine interleukin (IL)-1α (5 ng/ml). Control cultures contained mainly viable adherent cells and minor fractions of apoptotic detached cells and microparticles in the absence of inhibitors. In the presence of inhibitors, caspase 3 accumulated in adherent cells and detachment tended to increase. During incubation with either staurosporin or IL-1α in the absence of inhibitors of microparticle release, adherent cells remained viable, and detachment and EMP release increased slightly. In the presence of inhibitors, dramatic changes occurred in staurosporin-treated cultures. Caspase 3 accumulated in adherent cells and >90% of the cells detached within 48 hours. In IL-1α-treated cultures no accumulation of caspase 3 was observed in adherent cells, although detachment increased. Scanning electron microscopy studies confirmed the presence of EMP on both adherent and detached cells. Prolonged culture of detached cells indicated a rapid EMP formation as well as some EMP formation at longer culture periods. Inhibition of EMP release causes accumulation of caspase 3 and promotes cell detachment, although the extent depends on the kind of “external stress”. Thus, the release of caspase 3-containing microparticles may contribute to endothelial cell survival.
The influence on INRs and coagulation factors of the time span between blood sample collection and intake of phenprocoumon or acenocoumarol: Consequences for the assessment of the dose
Authors: Hutten Barbara , Péquériaux Nathalie , Haas Fred , Levi Marcel , Sturk Augueste , van Geest-Daalderop Johanna
Published: October 2007

Managing treatment with vitamin K antagonists, the prothrombin time (PT),expressed as international normalized ratio (INR), may not represent the INR during the entire 24 hour (h) period, and this variation may be different between long-acting phenprocoumon and short-acting acenocoumarol. For both drugs we investigated the variation in 24 h of the PT/INR, the consequences for the assessment of the doses and which vitamin K-dependent factor causes the daily variation. Patients on self-management took their medication at 6 p.m. and determined their INRs for eight weeks, once a week and three times daily (8.30 a.m., 6 p.m. and 11 p.m., thus 14.5 h, 24 h and 29 h after taking the medication, respectively). Acenocoumarol showed a significant variation in INRs over the 24 h period, with 22 out of 80 INRs >20% lower at 11 p.m. versus 8.30 a.m. Phenprocoumon showed only few variations. Patients managed by the anticoagulation clinic took their medication at 6 p.m. for four weeks and then at 8 a.m. for four weeks, 15 h and 25 h, respectively, before the weekly blood collection. PT/INR and coagulation factorsVII, X and II were determined. With acenocoumarol, taken 25 h before blood collection, the INRs were significantly different compared to 15 h, especially attributed to plasma levels of factorVII. Those on phenprocoumon were equal. These variations of INRs during 24 h may have major effects on the prescribed dose of short-acting vitamin K antagonists, such as acenocoumarol, especially for INRs at the limits of the therapeutic ranges.
Haemophilus somnus activation of brain endothelial cells: Potential role for local cytokine production and thrombosis in central nervous system (CNS) infection
Authors: Behling-Kelly Erica , Kim Kwang , Czuprynski Charles
Published: October 2007

Thrombotic meningoencephalitis (TME) is a neurological condition in cattle characterized by fibrinopurulent meningitis with hemorrhage, abscess formation and thrombotic vasculitis throughout the central nervous system. The etiologic agent of TME is Haemophilus somnus, a gram-negative pleomorphic coccobacillus. Although the pathogenesis of TME is not well understood, the propensity of H. somnus to cause vasculitis and intravascular thrombosis suggests a critical role for the interactions between the bacteria and endothelial cells in inciting the disease. The goal of this study was to determine if H. somnus elicits an inflammatory and procoagulative response in bovine brain micro- vascular endothelial cells (BBEC) in vitro. We demonstrate that BBEC exposed to H. somnus secrete significant levels of the proinflammatory and procoagulative cytokines TNF-α and IL-1β. BBEC treated with H. somnus also display increased levels of IL-6 mRNA,another cytokine associated with coagulopathy in vivo. H. somnus-treated BBEC exhibited increased procoagulant activity and tissue factor expression and activity,along with a decreased ability to activate protein C and decreased expression of thrombomodulin mRNA. These changes would be expected to promote thrombus formation in vessels of the CNS, and potentially contribute to the pathogenesis of TME.
Heme oxygenase-1 inducer hemin prevents vascular thrombosis
Authors: Desbuards Nicolas , Rochefort Gaël , Schlecht Deborah , Machet Marie-Christine , Halimi Jean-Michel , Eder Véronique , Hyvelin Jean-Marc , Antier Daniel
Published: October 2007

Hemin is a heme oxygenase-1 (HO-1) inducer which provides endogenous carbon monoxide known for playing roles in cell proliferation,inflammation or aggregation process. The objective of the current study was to examine the effect of prophylactic treatment with hemin in a thrombosis vascular model. Three groups of Wistar rats, control (n=6), hemin (n=6) and hemin+HO-1 inhibitor (n=6), were used for this study. Hemintreated animals received hemin (50 mg/kg/d; I.P.) for seven days and HO-1 inhibitor group received hemin at the same dose and SnPP IX (60 mg/kg/d; I.P.). All animals were exposed to electric stimulation of the left carotid according to Kawasaki’s procedure to induce reproducible thrombus formation. The hemin treatment did not induce blood pressure disturbance. Effects of hemin on vascular thrombosis were quantified by histopathology and its influence on haemostasis was assessed by measuring prothrombin time (PT), activated partial thromboplastin time (APTT) and blood parameters at the end of treatment. The HO-1 mRNA and protein level variation were also checked out. Results showed that chronic treatment with hemin significantly (p<0.01) reduced the vascular occlusion degree when compared to control and hemin SnPP groups with 7.2 ± 4.6 vs. 71.1 ± 14.7 and 74.0 ± 8.8%, respectively. Moreover, we observed significant (p<0.05) perturbations of blood parameters in hemintreated and hemin-SnPP treated rats. Interestingly, hemin treatment did not significantly increase both PT and APTT. Finally, the HO-1 mRNA and protein levels were increased in hemintreated carotid artery. In conclusion, hemin by inducing HO-1 expression may be a preventive agent against clinical disorders associated to an increased risk of thrombosis events and may limit haemorrhagic risks.
The role of heparin and allied compounds in the treatment of sepsis
Authors: Cornet Alexander , Smit Ellen , Beishuizen Albertus , Groeneveld A. B. Johan
Published: October 2007

The crosstalk between coagulation and inflammation and the propensity for microthromboembolic disease during sepsis calls for anticoagulant measures to prevent tissue hypoxygenation and to attenuate organ damage and dysfunction. Only one anticoagulant, recombinant human activated protein C (aPC, drotrecogin-α) has a proven survival benefit when used as an adjunctive therapy for human sepsis, partly because of its anti-inflammatory effect. However, heparin (-like compounds) may exert similar beneficial anti-inflammatory actions as aPC, in spite of the relatively narrow therapeutic window for anticoagulation. This narrative review is based on a Medline search of relevant basic and clinical studies published in English and discusses the potential role of heparin in modulating inflammatory responses in the treatment of animal models and human sepsis and its harmful sequelae. In any case, the results of a metaanalysis based on animal data suggest a potentially life-saving effect of heparin (-like compounds) in the treatment of sepsis.Therefore, a prospective randomized clinical trial is called upon to study effects in human sepsis.
Cardiovascular risk factors and global risk of fatal cardiovascular disease are positively correlated between partners of 802 married couples from different European countries
Authors: Castelnuovo Augusto Di , Quacquaruccio Gianni , Jozef Arnout , Cappuccio Francesco Paolo , Lorgeril Michel de , Dirckx Carla , Donati Maria Benedetta , Krogh Vittorio , Siani Alfonso , van Dongen Marten , Zito Francesco , Gaetano Giovanni de , Iacoviello Licia ,   European Collaborative Group of the IMMIDIET Project
Published: October 2007

Shared environmental factors may confer to spouses a similar risk for cardiovascular disease. We aimed at investigating in pairs the concordance in risk factors for cardiovascular disease and in global risk of cardiovascular events. In the framework of the IMMIDIET Project, married couples, recruited randomly from general practice, were studied. One thousand six hundred and four apparently healthy subjects aged 25–74 years from three different European populations were enrolled. Individual cardiovascular risks were estimated using SCORE risk equations. Age was strongly correlated within couples (r=0.86, P<0.0001). In multivariate model, within-pair correlation was high for social status (r=049; percentage of explained variation=24%) and percent of calories from lipids (r=0.34; 12%). Concerning conventional metabolic risk factors, percentage of explained variation varied from 0.5% (triglycerides) to 11% (glucose). Among new risk factors, activated factor VII showed the strongest correlation (r=0.28) and C-reactive protein the lowest (r=0.13). Either total, coronary or non-coronary risk estimates at 10 years were strongly correlated within pairs: the risk of a member explained about two thirds of the cardiovascular risk of the partner. Spouse pairs share common lifestyle habits, common and new metabolic risk factors and the predicted global risk of cardiovascular events. If the individual risk of a person is influenced by the risk of his/her partner, decreasing the risk in a member of the pair should also decrease the risk in the partner. These concepts may have important public health consequences in targeting screening or disease prevention measures towards partners of people with cardiovascular risk.
Activated protein C downregulates p38 mitogen-activated protein kinase and improves clinical parameters in an in-vivo model of septic shock
Authors: Nold-Petry Claudia , Fischer Doris , Richter Bernd , Blaheta Roman , Pfeilschifter Josef , Muhl Heiko , Schranz Dietmar , Veldman Alex , Nold Marcel
Published: October 2007

Despite the success of the anti-coagulant protease protein C (PC) in treating septic shock in humans, the signaling pathways used are still unclear. To explore the effects of treatment with PC zymogen and its activated form aPC in a setting of sepsis, we employed a piglet model of endotoxic shock. In the aPC group, we observed a 65%-90% reduction in plasmaTNF-alpha levels and a concomitant clinical improvement. Unexpectedly, administration of aPC also resulted in stabilization of the plasma pH above 7.2. Moreover, phosphorylated p38 mitogen-activated protein kinase (p38MAPK) was virtually absent in the livers of those piglets receiving aPC. In cultured human umbilical vein endothelial cells, we observed that nanomolar concentrations of PC and aPC inhibited the phosphorylation of p38MAPK. Furthermore, we showed that the regulation of the pro-apoptotic cell cycle regulator p53 by PC and aPC is dependent on the reduction of p38MAPK activation. The transduction of these effects involves all three receptors associated with protein C signaling, namely endothelial protein C receptor, protease-activated receptor 1, and sphingosine 1-phosphate receptor 1. Ultimately, this study elucidates novel signaling pathways regulated by protein C and emphasises the pivotal importance of its multiple modes of action beyond anticoagulation. APC’s clinical success may, in part, be due to p38MAPK inhibition.
Polymorphisms in the endothelial protein C receptor gene and thrombophilia
Authors: Medina Pilar , Navarro Silvia , Estellés Amparo , España Francisco
Published: October 2007

The protein C anticoagulant pathway plays a crucial role as a regulator of the blood clotting cascade. Protein C is activated on the vascular endothelial cell membrane by the thrombin-thrombomodulin complex. Once formed, activated protein C (APC) down-regulates thrombin formation by inactivating factors (F)Va and FVIIIa. Endothelial protein C receptor (EPCR) is able to bind protein C and increase the rate of protein C activation. Normal APC generation depends on the precise assemblage, on the surface of endothelial cells, of thrombin, thrombomodulin, protein C and EPCR.Therefore, any change in the efficiency of this assemblage may cause reduced/increased APC generation and modify the risk of thrombosis. This review highlights the different mutations/polymorphisms reported in the EPCR gene and their association with the risk of thrombosis.
Invasive procedures in the outpatient setting: Managing the short-acting acenocoumarol and the long-acting phenprocoumon
Authors: Hutten Barbara , Péquériaux Nathalie , de Vries-Goldschmeding Hanneke , Räkers Emmy , Levi Marcel , van Geest-Daalderop Johanna
Published: October 2007

Treatment with vitamin K antagonists (VKAs) has to be interrupted when invasive procedures are planned. We compared various methods of interruption in patients on acenocoumarol or phenprocoumon in a prospective study. In patients on acenocoumarol (n=141), 99 stopped three days before the intervention and 42 stopped two days before. All patients on phenprocoumon (n=111) received vitamin K two days before the intervention, and 55 of these patients discontinued phenprocoumon, whereas 56 did not stop. In a subset of 30 patients we determined International Normalized Ratios (INRs) and coagulation factors II,VII, X and protein C. The mean INR after stopping acenocoumarol for three days was significantly lower than after two days (1.1 vs. 1.3, p=<0.0001), but its clinical relevance may be trivial. In patients using phenprocoumon, the mean INR on the day of the intervention was only slightly lower after stopping the VKAs (1.5 vs. 1.6, p=0.0407), but a similar proportion of patients had an INR ≤1.4. On the day of the intervention, in the acenocoumarol group mean plasma levels of all coagulation factors were higher than 50% and in the phenprocoumon group higher than 25%. We conclude that acenocoumarol can be stopped two days before an invasive procedure that is associated with a low or moderate bleeding risk and three days before an intervention with a higher bleeding risk. For phenprocoumon, administration of vitamin K two days before an intervention results in an acceptable INR during the intervention, regardless whether phenprocoumon is interrupted or not.
Influence of lipids and obesity on haemorheological parameters in patients with deep vein thrombosis
Authors: Falcó Cristina , Simó María , Ferrando Fernando , Mira Yolanda , Todolí José , España Francisco , Corella Dolores , Vayá Amparo
Published: October 2007

It is not well established whether haemorheological alterations constitute independent risk factors for deep vein thrombosis (DVT).We have determined in 149 DVT patients and in 185 control subjects the body mass index (BMI), the haemorheological profile: blood viscosity (BV), plasma viscosity (PV), fibrinogen (Fg), erythrocyte aggregation (EA), erythrocyte deformability (ED) and plasma lipids. In the crude analysis BMI, Fg, PV, EA, triglycerides (TG) and ApoB were statistically higher and HDL cholesterol (HDL-Chol) statistically lower in DVT patients than in controls. No differences in BV and ED were observed. After BMI adjustment, Fg, PV and EA remained statistically higher in DVT cases than in controls (P=0.013; P=0.012; P=0.013; P=0.028, respectively). When the risk of DVT associated with these variables (using cut-offs that corresponded to the mean plus one SD of the control group) was estimated, EA>8.2 and PV>1.28 mPa·s were significantly associated with DVT even further adjustment for lipids and obesity (OR=2.78, P=0.004; OR=1.91, P=0.024, respectively). However, PV did not remain statistically significant after additional adjustment for Fg. When we consider together all the analyzed variables in order to control every variable for each other, TG>175 mg/dl (OR=3,2,P=0.004) and BMI>30 kg/m2 (OR=3.5, P=0.003), were also independently associated with a greater risk of DVT. Our results suggest that increased EA constitute an independent risk factor for DVT. However, when associated to hyperlipidaemia and obesity it further increases thrombotic risk.
Platelet-associated LIGHT (TNFSF14) mediates adhesion of platelets to human vascular endothelium
Authors: Stellos Konstantinos , May Andreas , Shankar Vijay , Kurz Kerstin , Katus Hugo , Celik Sultan , Langer Harald , Gawaz Meinrad , Dengler Thomas
Published: October 2007

LIGHT (TNFSF 14) belongs to the tumor necrosis factor super-family and is expressed by different types of immune cells. Recently, LIGHT was found to be associated with platelets and released upon activation. Activation of endothelial cells by recombinant LIGHT results in pro-inflammatory and pro-thrombotic changes, qualitatively comparable to effects of CD40 ligand. Given the important role of platelet-associated CD40 ligand in vascular inflammatory responses we investigated the role of LIGHT for activation of endothelium and adhesion of platelets to endothelial cells. Expression of LIGHT was detected on thrombocytes upon exposure to ADP or TRAP-1. The expression of the LIGHT receptors TR2 and LTβR on native human endothelial cells was confirmed by FACS analysis. LIGHT mediated adhesion of platelets to endothelium significantly, occurring both under static and dynamic flow conditions. This interaction was inhibited by a monoclonal antibody to LIGHT but not a control IgG. Moreover, in-vitro stimulation of endothelial cells with recombinant soluble human LIGHT (rhLIGHT) resulted in significantly increased transcriptional and translational upregulation of inflammatory markers ICAM-1, tissue factor (TF) and IL-8. This activation of endothelial cells by LIGHT was mediated by NFκB activation and qualitatively comparable to that induced by membrane-bound CD40-ligand on transfected cells. Furthermore, plasma levels of patients with myocardial infarction, in those with ST-elevation myocardial infarction (STEMI), showed increased plasma levels of LIGHT compared with healthy controls. In conclusion, platelet-associated LIGHT is involved in adhesion of platelets to endothelium while soluble LIGHT induces a pro-inflammatory state in vascular endothelial cells. LIGHT may thus be implicated in the pathogenesis of atherosclerosis and acute coronary syndrome, as evidenced by serum levels.
A two adenine insertion polymorphism in the 3’ untranslated region of factor VII gene is associated with peripheral arterial disease but not with venous thrombosis
Authors: Serve Emilie , Reny Jean-Luc , Akhavan Sepideh , Emmerich Joseph , Fischer Anne-Marie , Tapon-Bretaudière Jacqueline
Published: October 2007

Polymorphic variants of genes encoding blood coagulation proteins have been extensively studied as risk factors for venous or arterial thrombosis A variation in the 3' untranslated region (UTR) involved in the post-transcriptional regulation of factor VII (FVII) gene has been recently identified, a two adenine insertion/deletion at nucleotide 11293. In this study, we investigated its effect on the risk of thrombosis in the frame of two case-control studies, including patients suffering from peripheral arterial disease (PAD) or venous thromboembolic (VTE) disease. The 3’UTR FVII gene polymorphism was investigated i) in 181 patients who had symptomatic atherosclerotic disease of the lower limbs, ii) in 178 patients who had had at least one episode of objectively diagnosed deep venous thrombosis and iii) in controls matched for age and sex. Plasma FVII antigen (FVII:Ag) levels were lower in the presence of the 3’UTR 2A insertion (68.4 ± 12.3%, 81.3 ± 14.5% and 89.5 ± 13.7% in 2A/2A, 2A/0 and 0/0 subjects respectively, p<0.0001). No significant relationship was found with VTE disease. In the contrary we observed a lower risk of PAD for the 2A/2A compared to the 0/0 genotype after adjustment for traditional risk factors (hypercholesterolemia, smoking status, diabetes and hypertension), with an OR of 0.24 [95% CI 0.06–0.99]. In conclusion, the 2 adenine insertion in the 3’UTR of FVII gene, related to lower plasma FVII levels, is a genetic variation that may contribute to reduce the risk of PAD.
Prevalence of deep vein thrombosis (DVT) in non-surgical patients at hospital admission
Authors: Hoffmanns Wibke , Hoffmanns Phillip , Rapp Uli , Ames Michael , Pira Alessandro , Paar Dieter , Bramlage Peter , Diehm Curt , Lawall Holger
Published: October 2007

Venous thromboembolism (VTE) is known as a common complication in surgical and non-surgical patients. We hypothesized that according to the underlying risk factors and the acute illness, the prevalence of VTE in non-surgical patients admitted to hospital is widely underestimated. For three months each patient admitted to the department of internal medicine with an acute illness, but without known deep venous thrombosis (DVT) was investigated by ultrasound compression sonography. Patients’ history, risk factors and extent of immobilisation were documented. In patients with newly detected DVT D-dimer and fibrinogen were measured as well as computer tomography scans performed. Follow-up investigations of the DVT population were performed at four weeks and three months. Six hundred seventeen patients (49.3% men) were included. In 16 patients (men=7) a previously unknown thrombosis (2.6%) was detected, mainly in patients with acute cardio-pulmonary disease (56%) and the elderly (mean age 75.6 years). Eight patients had femoro-popliteal (50.0%), four a femoral (25.0%), and four a popliteal vein thrombosis (25.0%). Five had pulmonary embolism (31.3%). In patients with DVT D-dimer was 875 ± 1,228 mg/l, fibrinogen 568 ± 215 mg/dl and C-reactive-protein 58.54 ± 73.65 mg/dl. One patient died from sepsis during hospitalisation, one died from sudden cardiac death at home. None of the other 14 surviving patients relapsed. The study shows a 2.6% risk for DVT in outpatients with acute illness admitted to the department of internal medicine. These data demonstrate the high risk of DVT is in non-surgical patients. Early prophylaxis has to be considered in internal medicine patients especially in the elderly.
Adrenomedullin and endothelial barrier function
Authors: Temmesfeld-Wollbrück Bettina , Hocke Andreas , Suttorp Norbert , Hippenstiel Stefan
Published: October 2007

Although loss of endothelial barrier function is a hallmark of every acute inflammation and contributes to fatal loss of organ function during severe infections, there is no sufficient therapy for stabilization of endothelial barrier function. Endogenous peptide adrenomedullin (AM) serum levels were shown to be increased during severe infection including sepsis and septic shock. In different in-vitro and in-vivo models AM acted as a potent therapeutic endothelial barrier function-stabilizing agent. Activation of specific receptors by AM results in elevation of second messenger cAMP. AM inhibits actin-myosin based endothelial cell contraction and junctional disassembly, thereby preventing paracellular permeability and oedema formation. The peptide furthermore possesses several protective cardiovascular qualities, including protection of the microcirculation during inflammation, and was proven as an efficient counter-regulatory molecule in various models of sepsis and septic shock. Overall, AM may be an attractive molecule to combat against cardiovascular malfunction during severe infection.
Factor V Leiden and the etiology of inflammatory bowel disease
Authors: ten Kate Fiebo , te Velde Anje , Spek Arnold
Published: October 2007

Inflammatory bowel disease (IBD) refers to two chronic diseases that cause inflammation of the intestines: ulcerative colitis and Crohn’s disease. Patients suffering from IBD have a threefold increased risk of venous thrombosis compared with matched controls. Importantly, thromboembolic disease is a significant cause of morbidity and mortality in patients with IBD. However, despite several supporting observations it is still elusive whether activation of the blood coagulation cascade is involved in the etiology and pathogenesis of IBD. To confirm or refute the hypothesis that activated blood coagulation aggravates the development of IBD, we subjected wildtype and homozygous FV Leiden mice to a model of DSS-induced colitis. Experimental colitis led to a reduction in body weight, shortening of the colon and increased colon weight. In addition, DSS treatment led to ulcerations, edema formation, crypt loss, fibrosis and the influx of inflammatory cells into the colon. However, the FV Leiden genotype had no significant effect on any of the DSS-induced symptoms of colitis. We therefore conclude that the FV Leiden allele has no effect in murine colitis and we thus question the importance of activated blood coagulation in the etiology or pathogenesis of IBD.
Clinical outcome of patients with venous thromboembolism and renal insufficiency
Authors: Falgá Conxita , Capdevila Josep Antón , Soler Silvia , Rabuñal Ramón , Muñoz-Torrero Juan Francisco Sánchez , Gallego Pedro , Monreal Manuel ,   the RIETE Investigators
Published: October 2007

There is little information on the clinical outcome of patients with venous thromboembolism and renal insufficiency. RIETE is an ongoing, prospective registry of consecutive patients with acute, objectively confirmed, symptomatic deep vein thrombosis (DVT) or pulmonary embolism (PE). In this analysis we analyzed the three-month outcome in patients with creatinine clearance (CrCl) <30 ml/min. As of March 2007, 1,037 of the 18,251 (5.7%) patients enrolled in RIETE had CrCl <30 ml/min. During the three-month study period these patients had an increased incidence of fatal bleeding, fatal PE, and overall death compared to those with CrCl >30 ml/min. Of the 579 patients presenting with clinically overt PE, 52 (9.0%) died of the initial PE, 13 (2.2%) of recurrent PE, and nine (1.6%) died of bleeding complications. During the first 15 days of therapy the 10% incidence of fatal PE was 10-fold their 1.0% of fatal bleeding. From day 16 to 90, the 1.0% rate of fatal PE was not significantly higher than the 0.5% of fatal bleeding. Of the 458 DVT patients with CrCl <30 ml/min, 14 (3.1%) had fatal bleeding and only one (0.2%) died of PE. In patients with CrCl <30 ml/min presenting with clinically overt PE the main threat is PE itself. On the contrary, in those with DVT the main threat is bleeding.
ProTime self-management yielding improvement of fluency and quality of life
Authors: Völler Heinz , Taborski Uwe , Dovifat Clemens , Hartwig Ines , Kadar Janos , Wegscheider Karl , LaDuca Frank , Ansell Jack , Zucker Marcia
Published: October 2007

Patient self-management (PSM), as the standard of care for vitamin K-antagonist therapy management in Germany requires a detailed, point-of-care (POC) device-specific training program to ensure quality patient care. In a multi-center trial using the ProTime System (Training program plus POC device), 105 patients were enrolled to evaluate efficacy of training, knowledge retention, patient satisfaction and quality of life (QoL). Patients returned to the centers 1, 3 and 6 months after training to complete questionnaires and demonstrate INR test proficiency. Training assessment employed self-evaluation and comparison of POC results between PSM and professional operators. Patient satisfaction and QoL were assessed using a modification of the questionnaire described by Sawicki and the SF12v2 QoL Survey, respectively. Patients demonstrated statistically significant improvements in knowledge post training (p<0.001) and retained the acquired information (p=NS vs. post-training; N=45) after 6 months. Trained patients yielded equivalent INR results to professional operators (r=0.92) with little or no bias across all clinic visits. Compliance with weekly testing improved from 1 to 3 months (p = 0.03), remaining at the required weekly frequency through 6 months. Average patient satisfaction improved significantly during the first month and remained constant thereafter. There was a statistically significant improvement in the Physical Component Summary of SF12 between baseline and 3/6 month assessments in all centers. In conclusion, PSM requires a comprehensive system including appropriate disease and POC device training. Such a system fosters compliance, improved knowledge about underlying disease, patient satisfaction and QoL.

Footnote:

Portions of this trial were presented on November 15, 2005 at the American Heart Association Scientific Sessions 2005 in Dallas, TX, USA.
Factors with conformational effects on haemostatic serpins: Implications in thrombosis
Authors: Hernández-Espinosa David , Ordóñez Adriana , Vicente Vicente , Corral Javier
Published: October 2007

Serpins are key actors of systems involving proteolytic reactions, such as the haemostatic system, as they are irreversible suicide inhibitors of serine proteases. The structural flexibility and physical properties of serpins that are required for their efficient inhibitory mechanism also make them especially vulnerable to even minor factors that induce conformational changes in the native form of these molecules, leading to a number of inactive conformations, such as latent, cleaved or polymers. Increasing numbers of conformational mutations affecting haemostatic serpins, mainly antithrombin, the main endogenous anticoagulant, have been described. These mutations cause circulating deficiencies of the molecules, in most cases due to intracellular retention, which may be associated with a hyper-coagulable state. Indeed, conformational mutations in antithrombin have been identified in patients with severe venous thrombosis,which has led to the hypothesis that these disorders might be included in the group of conformational diseases. Moreover,we have recently demonstrated that other factors,including both drugs,such as the treatment with L-asparaginase,or environmental factors, such as high temperatures or hyperlipidemia, may also have conformational consequences on hepatic antithrombin,thus resulting in intracellular aggregation and plasma deficiency, which may increase the risk of thrombosis. In this study,we review the causes of deficiency of haemostatic serpins that may be explained by conformational mechanisms, and their association with an increased risk of venous thrombosis.
Effector functions of pathogenic Yersinia species
Authors: Trasak Claudia , Ruckdeschel Klaus , Aepfelbacher Martin
Published: October 2007

Pathogenic species of the genus Yersinia suppress and reorient the immune system to infect lymphatic tissues, inner organs and at times also the vasculature. For this purpose yersiniae employ a type III secretion system to translocate effector proteins (Yersinia outer proteins;Yops) into immune cells.Yops often exert unique biochemical activities for modulating the activity of Rho GTP-binding proteins, focal adhesion proteins, inflammatory pathways and cell survival/apoptosis. In this review we will put emphasis on the biochemistry, cell- and infection biology ofYersinia effector Yops.
The appended tail region of heparin cofactor II and additional reactive centre loop mutations combine to increase the reactivity and specificity of α1-proteinase inhibitor M358R for thrombin
Authors: Sutherland Jason , Bhakta Varsha , Sheffield William
Published: October 2007

Natural inhibitors of coagulation or inflammation such as the serpins antithrombin (AT), heparin cofactor II (HCII), and 1-proteinase inhibitor (α1-PI) can be overwhelmed in thrombosis and/or sepsis. The reactive centre (P1-P1) variant α1-PI M358R inhibits not only procoagulant thrombin but also anticoagulant activated protein C (APC). We previously described HAPI M358R, comprising a fusion of HCII residues 1–75 to the N-terminus of a1-PI M358R that yielded increased anti-thrombin, but not anti-APC activity. We hypothesized that further alterations to the HAPI M358R reactive centre loop would yield additional refinements in specificity. The reactions with thrombin or APC of recombinant α1-PI M358R variants with or without the HCII extension were characterized electrophoretically and kinetically. Their extension of clotting times and inhibition of fibrin-bound thrombin were measured, and the survival of HAPI M358R in mice was determined. Replacing the P7-P3 and P2’ residues of HAPI M358R with AT residues reduced APC inhibition rates by 140-fold, but those of thrombin less than two-fold;substituting the P16-P2 and P2’-P3’ residues of HAPI M358R with HCII residues reduced APC inhibition rates by 180-fold, but those of thrombin 10.5-fold. Fused variants extended thrombin clotting times more effectively than unfused inhibitors, were at least as effective at inhibiting clot-bound thrombin, and remained intact in the murine circulation. The combination of modifications inside and outside the RCL resulted in a 1,360-fold increase in selectivity of HAPI M358R (AT P7-P3/P2’) for thrombin versus APC relative to α1-PI M358R. Our results predict that this protein may be effective in limiting thrombosis in vivo.
Haemostatic efficacy and safety of bolus and continuous infusion of recombinant factor VIIa are comparable in haemophilia patients with inhibitors undergoing major surgery
Authors: Mathew Prasad , Valentino Leonard , Sumner Michael , Seremetis Stephanie , Hoots Keith , Pruthi Rajiv ,   the NovoSeven in Surgery Study Investigators
Published: October 2007

Bolus infusion (BI) recombinant factor VIIa (rFVIIa) administration is safe and effective in the surgical management of haemophilia patients with inhibitors but has not been compared directly with continuous infusion (CI). We conducted an open-label, randomized, multicenter trial comparing the efficacy and safety of rFVIIa administered by BI or CI for the surgical management of haemophilia A or B patients with inhibitors to FVIII or FIX. Safety was compared with that of a control group of noninhibitor patients receiving FVIII or FIX concentrates for major surgery. All inhibitor subjects received an initial bolus dose of 90 μg/kg rFVIIa and were then randomly assigned to BI (n=12) or CI (n=12). The BI group received 90 μg/kg rFVIIa every two hours (h) during surgery through day 5, then every four hours for days 6–10. The CI group received 50 μg/kg/h rFVIIa through day 5, then 25 mg/kg/h for days 6–10. The control group (n=12) received FVIII or FIX per institutional protocols. Twenty-two major surgeries included orthopedic procedures on the knee (n=13), hip (n=3), and abdominal/pelvis procedures (n=4). One patient with an autoimmune FVIII inhibitor randomized to the BI arm was excluded from efficacy analysis. Haemostatic efficacy of rFVIIa in each group was comparable: effective in 8/11 and 9/12 subjects in the BI and CI arms, respectively, and ineffective in three subjects in each arm. Serious adverse events were related to continued or increased bleeding. In conclusion, haemostatic efficacy and safety of BI and CI of rFVIIa are comparable for the surgical management of haemophilia subjects with inhibitors.
Impaired endothelial antithrombotic activity following short-term interruption of continuous subcutaneous insulin infusion in type1 diabetic patients
Authors: Federici Marco Orsini , Mourvaki Evangelia , Ferolla Piero , Piroddi Marta , Stabile Anna , Timi Alessandra , Celleno Roberta , Benedetti Massimo Massi , Iorio Alfonso
Published: October 2007

Review of literature has shown an increased rate of thrombotic complications in diabetic patients with frequent episodes of hyperketonemia. However, the mechanisms by which ketosis promotes vascular disease in diabetic patients are unclear.It was the aim of this study to investigate early changes in haemostatic parameters and oxidative stress markers during the hyperketonemic status which follows the interruption of continuous subcutaneous insulin infusion (CSII) in type I diabetic patients. Eight CSII-treated type I diabetic patients underwent a 4-hour pump arrest. Blood glucose, insulin and 3-hydroxybutirate were measured to verify the metabolic response. A vein-occlusive (VO) test was performed for the determination of tPA and PAI-1 activities and their antigen levels before and after the CSII arrest. Coagulation factor VII and VIII were evaluated by one-stage PT and PTT method, respectively.TF, vWF, tPA and PAI-1 antigens were determined by ELISA, whereas tPA and PAI-1 activities using chromogenic methods. Plasma malondialdehyde (MDA) and protein carbonyl groups (PCG) levels were determined by HPLC and spectrophotometry, respectively. After the insulin deprivation phase, post-VO tPA antigen level significantly decreased (P=0.0391), whereas TF and post-VO PAI-1 activity and antigen levels significantly increased (P=0.0156 and P=0.0234, respectively). Plasma MDA and PCG levels were 1.88-fold and 1.74-fold higher than baseline values, respectively. In conclusion, the impairment of the fibrinolytic potential and the increases in TF, MDA and PCG levels may enhance the risk of both arterial and venous thrombosis during ketosis.Thus, early detection of hyperketonemia in DM patients could contribute to the prevention of life-threatening vascular events.
A large deletion of the PROS1 gene in a deep vein thrombosis patient with protein S deficiency
Authors: Yin Tong , Takeshita Satoshi , Sato Yukiko , Sakata Toshiyuki , Shin Yongchol , Honda Shigenori , Kawasaki Tomio , Tsuji Hajime , Kojima Tetsuhito , Madoiwa Seiji , Sakata Yoichi , Murata Mitsuru , Ikeda Yasuo , Miyata Toshiyuki
Published: October 2007

Inherited deficiency of protein S encoded by the PROS1 gene constitutes an important risk factor for deep vein thrombosis (DVT). Nevertheless, although more than 200 deleterious genetic variations in PROS1 have been identified, causative point mutations of PROS1 gene are not detected in approximately half of protein S-deficient families. The present study investigated whether there may exist a large deletion in PROS1 that constitutes a genetic risk factor for Japanese DVT patients. A multiplex ligation-dependent probe amplification analysis was employed to identify the deletions in PROS1 in 163 Japanese patients with DVT. A large gene deletion was identified in one patient who showed 16% protein S activity and did not carry point mutations in PROS1 by DNA sequencing and it was validated by the quantitative PCR method. The deletion spanned at least the whole PROS1 gene (107 kb) and at most from the centromere located downstream of PROS1, to before the D3S3619 marker, the first heterozygous marker in the upstream of PROS1 in chromosome 3. In conclusion, a large deletion in PROS1 was shown to partly account for DVT with protein S deficiency. Screening for large deletions in PROS1 might be warranted in PROS1 causative point mutation-negative DVT patients with protein S deficiency.
Leptin signalling and leptin-mediated activation of human platelets: Importance of JAK2 and the phospholipases Cγ2 and A2
Authors: Dellas Claudia , Schäfer Katrin , Rohm Ilonka , Lankeit Mareike , Leifheit Maren , Hasenfuss Gerd , Loskutoff David , Konstantinides Stavros
Published: October 2007

Leptin enhances agonist-induced platelet aggregation, and human platelets have been reported to express the leptin receptor. However, the pathways and mediators lying downstream of leptin binding to platelets remain, with few exceptions, unknown. In the present study, we sought to gain further insight into the possible role of leptin as a platelet agonist. Stimulation of platelets with leptin promoted thromboxane generation and activation of αIIbβ3, as demonstrated by PAC-1 binding. Furthermore, it increased the adhesion to immobilised fibrinogen (p<0.001) and induced cytoskeletal rearrangement of both platelets and Meg01 cells. Leptin time- and dose-dependently phosphorylated the intracellular signalling molecules JAK2 and STAT3, although the importance of STAT3 for leptin-induced platelet activation remains to be determined. Important intracellular mediators and pathways activated by leptin downstream of JAK2 were found to include phosphatidylinositol-3 kinase, phospholipase Cγ2 and protein kinase C, as well as the p38 MAP kinase-phospholipase A2 axis. Accordingly, incubation with the specific inhibitors AG490, Ly294002, U73122, and SB203580 prevented leptin-mediated platelet activation. These results help delineate biologically relevant leptin signalling pathways in platelets and may improve our understanding of the mechanisms linking hyperleptinaemia to the increased thrombosis risk in human obesity.