bluuebunny/crossref_metadata_2025 huggingface dataset:
Significance of Low-Dose and Standard-Dose ACTH Tests Compared to Overnight Metyrapone Test in the Diagnosis of Adrenal Insufficiency in Childhood
Authors: Gonc E. Nazlı , Kandemir Nurgun , Kinik Sibel T.
Published: October 2003

Objective: To discover the value of low-dose (LDAT) and standard-dose ACTH tests (SDAT) as compared with the metyrapone test in the diagnosis of secondary adrenal insufficiency. Patients and Methods: LDAT (0.5 µg/m2), SDAT (250 µg/m2) and overnight metyrapone (30 mg/kg) tests were carried out in 29 patients with suspected adrenal insufficiency. LDAT and SDAT were also performed in 36 control subjects. Results: 18 of 29 patients were grouped in the adrenal-sufficient (AS) group and 11 of 29 patients in the adrenal-deficient (AD) group according to the metyrapone test results. The control group had significantly higher cortisol responses than the AS and AD groups during LDAT. The control group had similar cortisol responses to the AS group but higher cortisol responses than the AD group during SDAT. The AS group was divided into 2 subgroups: AS patients with multiple pituitary hormone deficiencies (AS-multiple) and AS patients with idiopathic growth hormone deficiencies (AS-isolated). The AS-multiple group had statistically lower cortisol responses than the control group during LDAT. Receiver-operating characteristics analysis revealed that the cortisol cutoff value in LDAT was 19.8 µg/dl (100% sensitivity, 89% specificity) and 30.4 µg/dl in SDAT (82% sensitivity, 78% specificity). Conclusion: LDAT is capable of identifying patients with adrenal insufficiency more effectively than SDAT. The cortisol cutoff value in LDAT was calculated as 19.8 µg/dl with 100% sensitivity. AS patients with multiple pituitary hormone deficiencies had lower cortisol responses to LDAT than the control group implying that these patients might have a lower cortisol secretory capacity than healthy subjects.
The Uterine Length in Women with Turner Syndrome Reflects the Postmenarcheal Daily Estrogen Dose
Authors: Snajderova Marta , Mardesic Tonko , Lebl Jan , Gerzova Hedvika , Teslik Leos , Zapletalova Jirina
Published: October 2003

Aim: To evaluate the effects of estrogen substitution on the uterine development in patients with Turner syndrome. Method: 57 women, aged 18.1–41.5 years, were treated with estrogen from puberty induction. Results: In 21 women (37%), the uterus developed to >65 mm in length. The daily estrogen dose correlated with both uterine length (r = 0.29; p < 0.05) and Tanner breast stage (r = 0.44; p < 0.001). A negative correlation between age at artificial menarche and uterine length was found (r = –0.29; p < 0.05). The endometrium thickness was greater in women with an uterus length >65 mm (p < 0.05). In 50% of the women (18 were evaluated), an adult-shaped uterus developed. Previous growth hormone therapy (n = 32) had no impact on the uterus length. Conclusions: The uterine development was suboptimal in most patients. Further investigation is needed to optimize estrogen therapy for uterine development in patients with Turner syndrome.
Scintigraphy with [111In]Octreotide and 201Tl in a Hürthle Cell Thyroid Carcinoma without Detectable Radio-Iodine Uptake
Authors: Kostoglou-Athanassiou I. , Pappas A. , Gogou L. , Kaldrymides P.
Published: October 2003

Aim: To describe the visualization of recurrent disease by [111In]octreotide and 201Tl scintigraphy in a patient with Hürthle cell thyroid carcinoma, increased thyroglobulin levels, and a negative radio-iodine total-body scan. Methods: Scintigraphy with [111In]octreotide and 201Tl was performed, and a local recurrence in the thyroid bed was detected which was excised by surgery. Results: On histology, the tumour proved to be a Hürthle cell carcinoma, and within the tumour somatostatin receptors were detected by RT-PCR. Conclusion: Scintigraphy with [111In]octreotide and 201Tl is an alternative imaging method for the detection of residual disease in patients with a differentiated thyroid carcinoma having increased thyroglobulin levels and a negative radio-iodine total-body scan.
Soluble E-selectin in cardiovascular disease and its risk factors
Authors: Roldán Vanessa , Marín Francisco , Lip Gregory , Blann Andrew
Published: October 2003

The initial steps in the pathogenesis of atherosclerosis involve changes to the vascular endothelium, which produces numerous substances involved in the regulation and maintenance of vascular integrity and the homeostasis of the coagulation/fibrinolysis system. A further change in endothelial physiology is an increase in the surface expression of cell adhesion molecules, such as E-selectin, which regulate adhesive interactions between certain blood cells and endothelium. As E-selectin is only expressed on activated endothelium, it therefore provides an opportunity to study pathophysiological aspects of this cell in cardiovascular and other disease. However, a soluble form of E selectin (i.e. sE-selectin) can be found in the plasma. This review will focus on sE-selectin, and its potential role in the pathogenesis of cardiovascular disease as raised levels have been found in hypertension, diabetes and hyperlipidemia, although its association in established atherosclerosis disease and its value as a prognostic factor is more controversial.

Search strategy: We performed a keyword search (listed above) using electronic databases (PUB-MED, MEDLINE, EMBASE, DARE), and additionally, abstracts from national and international cardiovascular meetings were studied to identify unpublished studies. Relevant authors of these studies were contacted to obtain further data.
Allele 4G of gene PAI-1 associated with prothrombin mutation G20210A increases the risk for venous thrombosis
Authors: Barcellona Doris , Fenu Lara , Cauli Cristiana , Pisu Giulia , Marongiu Francesco
Published: October 2003

Several studies have tried to clarify the role of polymorphism 4G/5G of the PAI-1 gene in venous thromboembolism without reaching any final conclusion. It has been demonstrated that this polymorphism may induce an increased risk for venous thromboembolism (VTE) in patients with thrombophilic defects. We studied the association of prothrombin mutation G20210A with 4G/5G polymorphism in 402 VTE patients and 466 healthy controls. Patients affected by prothrombin mutation G20210A, with or without the concomitant presence of allele 4G, had a 3.7 thrombotic risk (C.I. 95% 2.3–6.0; p<0.0001). Moreover, genotype 4G/4G is a mild risk factor for VTE, irrespectively of whether the prothrombin mutation was present.

Logistic regression analysis showed that patients carrying the G20210A prothrombin mutation with allele 4G gave an odds ratio for VTE of 6.1 (C.I. 95% 3.2 – 11.4; p<0.001). The risk increased up to 13.0 (C.I. 95% 3.0 – 60.4; p<0.001) when we considered the association of the prothrombin mutation with genotype 4G/4G. The G20210A mutation without allele 4G (5G/5G) was not a risk factor for VTE. In conclusion, we believe that patients affected by VTE with concomitant presence of the G20210A prothrombin mutation could be tested for genotype 4G/4G to better define their thrombotic risk.
Markers of endothelial activation and atherothrombosis in women with history of preeclampsia or gestational hypertension
Authors: Ford Isobel , Morrison Rona , Prescott Gordon , Watson Stuart , Hannaford Philip , Smith Cairns , Campbell Doris , Greaves Michael , Vickers Mark
Published: October 2003

Women who have had preeclampsia (PE) or gestational hypertension (GH) exhibit relatively high rates of circulatory diseases. PE is a disease associated with inflammation and vascular endothelial dysfunction. We therefore hypothesised that women with a history of PE or GH might have abnormal levels of markers of endothelial activation or inflammation, reflecting either an innate predisposition to preeclampsia or changes induced by the eclamptic process. Levels of von Willebrand factor, fibrinogen and C-reactive protein were compared in 392 women with a history of PE between 1951 and 1970, 297 women with a history of GH and 163 matched controls. Although no significant differences between those with either PE or GH and controls were noted, subjects with a history of PE had significantly higher CRP values than those with GH. No significant differences were found when the three groups were compared for von Willebrand factor or fibrinogen. Overall, the data do not support our hypothesis.

In addition, our data document increasing von Willebrand factor levels increase with age, which may help explain the age dependent increase in venous or arterial thrombosis. Moderate alcohol consumption was also associated with lower levels of inflammatory markers.
Reduction of venous thromboembolism following prolonged prophylaxis with the low molecular weight heparin Certoparin after endoprothetic joint replacement or osteosynthesis of the lower limb in elderly patients
Authors: Bodamer Iris , Galster Heide , Seidlmayer Christoph , Grambach Konrad , Koudela Karel , Eisele Ralf , Becker Clemens , Paal Valerie , Spannagel Uwe , Brom Joachim , Weidinger Gottfried , Kolb Gerald
Published: October 2003

The peri- and postsurgical thromboembolic prophylaxis with low molecular weight heparins is a well established therapy regimen, but the optimum duration of prophylaxis after surgery still remains uncertain. A few studies have pointed to the fact that the thromboembolic risk of high-risk patients persists longer than the in-hospital period correlating with respective hypercoagulatory conditions. The aim of the present study was to test if a prolongation of thromboprophylaxis with the low molecular weight heparin Certoparin further reduces the rate of thromboembolism in high-risk patients after orthopedic surgery. The “Long-term Thromboprophylaxis”-Study was a multicenter, randomized, double-blind, placebo-controlled trial. 360 patients who underwent endoprothetic joint replacement or osteosyn-thesis of the lower limb were initially enrolled, all of them received prophylactically 3000 U anti-Xa of Certoparin once daily for 14 days followed by randomization to prolonged Certoparin application or to placebo up to day 42. Patients were screened for deep vein thrombosis by sonography every week. Coagulation markers (fibrin monomers and D-dimers) were determined during the course of the study.

Venous thromboembolism during the prolongation period was observed in 18 patients receiving placebo versus 8 patients of the prolonged Certoparin group (12.1% versus 5.0%, intention-to-treat sample). The analysis revealed a statistically significant difference in favor of Certoparin (p=0.020), which was confirmed by per-protocol analysis (14.2% versus 5.5%, p=0.012). The differences remained significant, if analyses considered only clinically symptomatic thromboembolic events (p=0.040). Patients who developed a thrombosis showed a strong increase of coagulation markers as compared to patients without subsequent thrombosis. The respective differentiation started around 18 days before diagnosis of thrombosis. Only one minor bleeding complication was observed during prolonged Certoparin prophylaxis.

The present study shows that patients after joint replacement or osteosynthesis of the lower extremities have a persisting risk to develop thromboembolic complications beyond the routine duration of thromboprophylaxis. Extended prophylaxis with Certoparin resulted in a significantly lower rate of thromboembolism and should be strongly recommended.
A multi-centre collaborative study on the potency estimation of ReFacto
Authors: Sands Dawn , Sandberg Eva , Seitz Rainer , Barrowcliffe Trevor , Hubbard Anthony
Published: October 2003

Seven laboratories estimated factor VIII coagulant activity in recombinant B-domain-deleted (ReFacto) and plasma-derived FVIII concentrates (Octonativ-M) using chromogenic methods relative to the WHO 6th International Standard FVIII Concentrate (WHO 6th IS), European Pharmacopoeia BRP#2 (EP#2) and the ReFacto Laboratory Standard (RLS). Significantly higher estimates were obtained for all batches of product when calculated relative to the RLS in comparison with estimates vs WHO 6th IS and EP#2. Mean estimates for two batches of ReFacto product vs the RLS were within 10% of the labelled potency whereas estimates vs WHO 6th IS and EP#2 ranged from 21 to 31% lower than the label. Conversely, mean estimates for Octonativ-M relative to WHO 6th IS and EP#2 were within 10% of the label whereas the mean estimate vs RLS was 117% of label. Mean estimates for the ReFacto product, vs the WHO 6th IS and EP#2, varied considerably between the different chromogenic kits whereas estimates vs the RLS showed good agreement between kits. Mean estimates for the RLS vs the WHO 6th IS (8.10 IU/vial) and the EP#2 (7.66 IU/vial) were lower than the assigned value of 9.4 IU/vial. The results are consistent with ReFacto and full-length FVIII responding differently to variations in assay methodology and also indicate that the assigned value on the RLS may be too high. Since this study the unitage on the RLS has been adjusted to effectively increase the amount of ReFacto in the product by 20%.
Assessment of platelet activation in several different anticoagulants by the Advia 120 Hematology System, fluorescence flow cytometry, and electron microscopy
Authors: Chapman Sabrinah , Lépine Mariette , Okrongly David , Pujol-Moix Nuria , Hernández Angel , Boughrassa Faiza , Grant Andrew , Ahnadi Charaf
Published: October 2003

In vivoplatelet activation results are often confounded by activation induced in vitroduring the preparative procedures. We measured ex vivo(basal) and in vitro(thrombin-induced) platelet activation in sodium citrate, ethylenediaminetetraacetic acid (EDTA), and Citrate Theophylline Dipyridamole Adenosine (CTAD) whole blood specimens. Determinations were made by measurements of platelet density (mean platelet component: MPC concentration) on the Advia 120 Hematology System. The MPC has been previously shown to correlate with a fluorescence flow cytometric method, also determined in this study, using the surface expression of CD62P. Moreover, platelet shape and structure changes in EDTA and CTAD anticoagulated whole blood specimens were characterized by transmission electron microscopy (TEM). Observations made using the Advia 120 Hematology System platelet density parameter, MPC, in the absence of thrombin were 25.7 ± 0.9 g/dl, 27.9 ± 0.9 g/dl and 24.8 ± 1.2 g/dl in sodium citrate, EDTA and CTAD whole blood specimens, respectively. Addition of thrombin induced a significant change in platelet MPC for sodium citrate (21.9 ± 1.9 g/dl; p<0.0001) and EDTA (23.2 ± 0.9 g/dl; p<0.0001) whole blood specimens. In contrast, thrombin had no effect on MPC measured in whole blood taken into CTAD tubes. In vitrofluorescence flow cytometric platelet activation experiments measuring the percentage of platelets expressing anti-CD62P showed increase in sodium citrate specimens from 9.2 ± 7.0 to 55.5 ± 23.1 % (p<0.0001) and in EDTA specimens from 1.9 ± 1.7 to 64.6 ± 12.4 % (p<0.0001) after addition of thrombin. However, in blood taken into CTAD tubes, there was no significant change. Studies on platelets isolated from whole blood in CTAD showed activation by thrombin indicating that platelets in CTAD, while protected in its presence remained functional upon its removal. When observed by TEM over time, platelets in EDTA appear more activated and contain fewer granules than platelets in CTAD. We conclude that CTAD demonstrates in vitroplatelet activation inhibition and may be useful in stabilizing ex vivoplatelet activation. The novel platelet activation parameter, MPC, measured by an automated routine hematology system, using customized proprietary software, may be used in conjunction with CTAD, a stabilizing anticoagulant, to measure the ex vivoplatelet activation state in whole blood specimens. TEM studies verify shape modifications and simultaneous retention of intracellular granules at early post-venipuncture time periods in CTAD specimens.
Hemostatic risk factors in ischemic stroke
Authors: Berger Daniela , Mattle Heinrich , Lämmle Bernhard , Wuillemin Walter , Demarmels Biasiutti Franziska
Published: October 2003

The role played by hemostasis in the pathogenesis of ischemic stroke is still controversial. In the present study, we looked for a possible association of ischemic stroke and high clotting activity of factor II (FII:C), factor V (FV:C), factor VII (FVII:C), factor X (FX:C) and fibrinogen. We investigated 157 non-anti-coagulated patients (86 males, 71 females; median age 41 y, range 16-73 ), who had survived ischemic stroke for at least 2 months, and 193 healthy controls with similar age and sex distribution (104 males, 89 females; median age 39 y, range 19-74). Patients showed significantly higher body mass index, as well as significantly higher prevalence of arterial hypertension, smoking and hyperlipidemia. FV:C (p = 0.05), FX:C (p = 0.04) and fibrinogen (p = 0.05) were higher in patients as compared to controls. In a univariate risk analysis FX:C and FV:C were associated with the relative risk for ischemic stroke showing an odds ratio (OR) of up to 2.8 (95% CI: 1.05-7.6) and 3.4 (95%CI: 1.4-7.9), respectively, for levels above 130%. In a multivariate analysis using a logistic regression model including age, sex, arterial hypertension, smoking habit, diabetes, hyperlipidemia, BMI and the coagulation factors, FV:C was still found to significantly (p=0.03) add to the risk of ischemic stroke. An increase of factor FV:C by 10% was associated with an increase in the relative risk of 19% (95% CI.: 2%-38%). In conclusion, we found a high plasma level of FV:C to be a prevalent (FV:C > 130% in 20/157 patients) and independent risk factor for ischemic stroke.
Platelet membrane glycoprotein polymorphisms do not influence the clinical expressivity of von Willebrand disease type 1
Authors: Quiroga Teresa , Pereira Elisa , Morales María , Goycoolea Manuela , Hidalgo Patricia , Prieto Carolina , Mezzano Diego , Pereira Jaime
Published: October 2003

Von Willebrand disease (VWD) is characterized by a significant variation in bleeding symptoms among patients with similar laboratory profiles and equivalent plasma levels of von Willebrand factor (VWF) activities. Considering the recent suggestion that platelet membrane glycoprotein polymorphisms (PltGPs) may play a role as modulators of thromboembolic or haemorrhagic diseases, we investigated the role of different PltGPs and GPVI content in the clinical expression of patients with VWD type 1. The diagnosis of VWD (n = 76) was based on laboratory findings (VWF:Ag, VWF:RCo, VWF:CB, FVIII:C, and multimer analysis), family and personal history of bleeding. All patients were interviewed using a standardized questionnaire, and classified into two categories: bleeders (unequivocal bleeding tendency, n = 53) and non bleeders (absence of bleeding symptoms, n = 23). PltGPs, HPA-1, 2 and 5 and C807T of GPIa were determined by fluorophore-labelled hybridization probes on a LightCyclerTM. GPVI content was measured by western blotting.

VWF:Ag, VWF:RCo, VWF:CB and FVIII:C levels were not significantly different between symptomatic and asymptomatic patients. There were no differences in the genotype distribution and allele frequencies between bleeders and non bleeders for the platelet alloantigen systems HPA-1, 2, 5 and the GPIa C807T polymorphism. The levels of platelet GPVI were similar in symptomatic and asymptomatic VWD patients (109.6 ± 58.4 vs 114.1 ± 52.5, respectively; p: 0.77). These results show that PltGPs HPA-1, 2 and 5 or the C807T dimorphism of GPIa do not influence the clinical expressivity of VWD type 1. The wide variation in GPVI content was not associated with the severity of bleeding in the patients. Other genetic factors that may contribute to the variable expressivity of VWD type 1 should be investigated.
Antiinflammatory activity of astragaloside IV is mediated by inhibition of NF-κB activation and adhesion molecule expression
Authors: Zhang Wei-Jian , Hufnagl Peter , Binder Bernd , Wojta Johann
Published: October 2003

The regulated expression of adhesion molecules on the surface of endothelial cells is a key process in the pathogenesis of inflammation. The saponin astragaloside IV (AS-IV), a 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol purified from the Chinese medical herb Astragalus membranaceus(Fisch) Bge.has been shown to have anti-inflammatory effects in vivo.In this study we have investigated the effect of AS-IV on cytokine-and LPS-stimulated expression of adhesion molecules in and leukocyte adhesion to endothelial cells. We have demonstrated that AS-IV significantly reduced the adhesion promoting activity of LPS-stimulated HUVECs for polymorph-nuclear leukocytes (PMNs) and the monocytic cell line THP-1. Furthermore, by using specific cell ELISAs we could show that AS-IV decreased the LPS-induced expression of E-selectin and VCAM-1 on the surface of HUVECs in a dose and time dependent manner, whereas the expression of ICAM-1 was not affected by AS-IV. AS-IV also inhibits TNFβ-induced VCAM-1 expression. The saponin octyl-D-glucopyranoside had no effect on the LPS-induced expression of E-selectin and VCAM-1 excluding an unspecific detergent-like effect of AS-IV. Moreover, AS-IV significantly inhibited LPS- and TNFβ-induced specific mRNA levels for E-selectin and VCAM-1. Finally, we could show that AS-IV completely abolished LPS- and TNFα-induced nuclear translocation of NF-κB and NF-κB DNA binding activity in endothelial cells. We conclude that the ability of AS-IV to inhibit the NF-κB pathway might be one underlying mechanism contributing to its anti-inflammatory potential in vivo.
Exclusion of pulmonary embolism using C-reactive protein and D-dimer
Authors: Hayoz Daniel , Yersin Bertrand , Perrier Arnaud , Barghouth Ghassan , Schnyder Pierre , Bischof-Delaloye Angelika , Cornuz Jacques , Aujesky Drahomir
Published: October 2003

Our goal was to evaluate the diagnostic utility of C-reactive protein (CRP) alone or combined with clinical probability assessment in patients with suspected pulmonary embolism (PE), and to compare its performance to a D-dimer assay. We conducted a prospective study in which we performed a common immuno-turbidimetric CRP test and a rapid enzyme-linked immunosorbent assay (ELISA) D-dimer test in 259 consecutive outpatients with suspected PE at the emergency department of a teaching hospital. We assessed clinical probability of PE by a validated prediction rule overridden by clinical judgment. Patients with D-dimer levels ≥ 500 µg/l underwent a work-up consisting of lower-limb venous ultrasound, spiral computer-ized tomography, ventilation-perfusion scan, or pulmonary angiography. Patients were followed up for three months. Seventy-seven (30%) of the patients had PE.The CRP alone had a sensitivity of 84% (95% confidence interval [CI).: 74 to 92%) and a negative predictive value (NPV) of 87% (95% CI: 78 to 93%) at a cutpoint of 5 mg/l. Overall, 61 (24%) patients with a low clinical probability of PE had a CRP < 5 mg/l. Due to the low prevalence of PE (9%) in this subgroup, the NPV increased to 97% (95% CI: 89 to 100%). The D-dimer (cutpoint 500 µg/l) showed a sensitivity of 100% (95% CI: 95 to 100%) and a NPV of 100% (95% CI: 94 to 100%) irrespective of clinical probability and accurately rule out PE in 56 (22%) patients. Standard CRP tests alone or combined with clinical probability assessment cannot safely exclude PE.
Intracellular alkalinization augments capacitative Ca2+ entry in platelets
Authors: Marumo Mikio , Wakabayashi Ichiro
Published: October 2003

In order to elucidate the significance of intracellular alkalinization in signal transduction of platelets, we investigated the effects on capacitative Ca2+ entry (CCE) of intracellular alkalinization that was induced by NH4Cl. Addition of NH4Cl (10 mM) to the medium resulted in an elevation of intracellular pH by about 0.35, which was eliminated by simultaneous addition of propionate (20 mM), an inducer of intracellular acidification, to the medium. CCE was induced by an extracellular addition of Ca2+ to platelets in which Ca2+ stores had been depleted by stimulation with thapsigargin in nominally Ca2+-free medium. NH4Cl markedly augmented CCE and subsequent platelet aggregation, both of which were abolished in the presence of SKF-96365, an inhibitor of capacitative Ca2+ entry in non-excitable cells such as platelets. The augmentation of CCE and subsequent aggregation by NH4Cl was not observed in the presence of propionate or SKF-96365. Extracellular alkalosis induced by Tris also markedly augmented CCE and subsequent aggregation. These augmenting effects of extracellular alkalosis by Tris were significantly but incompletely inhibited by simultaneous addition of propionate (20 mM), which completely eliminated elevation of intracellular pH elicited by Tris. Thus, the augmenting effect of extracellular alkalosis on CCE was in part mediated by intracellular alkalosis. These findings suggest that intracellular alkalinization is a potent signal that augments CCE in platelets.
The effects of different alcoholic drinks on lipids, insulin and haemostatic and inflammatory markers in older men
Authors: Lowe Gordon , Shaper Gerald , Whincup Peter , Rumley Ann , Walker Mary , Lennon Lucy , Goya Wannamethee Sasiwarang
Published: October 2003

Light to moderate drinking is associated with lower risk of coronary heart (CHD) than non-drinkers. We have examined the relationships between total alcohol intake and type of alcoholic beverage and several potential biological mechanisms.

We carried out the study in 3158 men aged 60-79 years drawn from general practices in 24 British towns with no history of myocardial infarction, stroke or diabetes and who were not on warfarin. Total alcohol consumption showed a significant positive dose-response relationship with high density lipoprotein cholesterol (HDL-C), coagulation factor IX, haematocrit, blood viscosity, and tissue plasminogen (t-PA) antigen, and an inverse dose-response relationship with insulin, fibrinogen, von Willebrand factor (vWF) and triglycerides after adjustment for possible confounders. Total alcohol consumption showed weak associations with plasma viscosity and fibrin D-dimer, and no association with factors VII, VIII, or C-reactive protein (CRP). Wine was specifically associated with lower CRP, plasma viscosity, factor VIII and triglycerides.

The findings are consistent with the suggestion that HDL-C in particular but also insulin and haemostatic factors may contribute to the beneficial effect of light to moderate drinking on risk of CHD.Wine has effects that may confer greater protection than other alcoholic beverages.
Increased leukocyte-platelet adhesion in patients with graft occlusion after peripheral vascular surgery
Authors: Esposito Claire , Popescu Wanda , Rinder Henry , Schwartz Jeffrey , Smith Brian , Rinder Christine
Published: October 2003

Graft occlusion following peripheral vascular surgery is attributable to some combination of acute thrombosis, and progression of atherosclerosis: interactions between leukocytes and activated platelets may play a role in both of these processes. This investigation measured perioperative leukocyte-platelet conjugate formation, and leukocyte and platelet activation in 46 patients undergoing surgery for lower extremity peripheral vascular disease (PVD). All patients were followed for graft patency over the next 6 months; 27 patients had grafts that remained patent while 19 had graft occlusion. On postoperative day #1 (POD#1), the graft occlusion group demonstrated a significantly greater increase in circulating levels of both mono-cyteplatelet and neutrophil (PMN)-platelet conjugates compared to the patent graft patients (p=0.015 and 0.018, respectively). PMN activation, assessed by increases in surface CD11b expression, was also significantly increased on POD#1 in the graft occlusion group compared to the patent group (p=0.026). The percentage of circulating activated (CD62P+) platelets did not differ between groups, but patients with graft occlusion demonstrated a higher percentage of younger, reticulated platelets throughout the study period (p=0.008), indicating increased platelet turnover.

We conclude that in the early postoperative period, leukocyte-platelet adhesion, PMN activation, and platelet turnover are significantly greater in PVD patients who go on to develop later graft occlusion. Cellular activation and heterotypic cell interactions in peripheral vascular surgery patients may be important in the etiologies of thrombosis and/or accelerated atherosclerosis leading to graft loss.
Blockade of GPIIb/IIIa by eptifibatide and tirofiban does not alter tissue factor induced thrombin generation in human endotoxemia
Authors: Derhaschnig Ulla , Pachinger Christine , Schweeger-Exeli Ingrid , Marsik Claudia , Jilma Bernd
Published: October 2003

Activated platelets facilitate thrombin generation by providing a catalytic surface on which coagulation activation occurs. The glycoprotein (GP) IIb/IIIa receptor might play a major role in this process as shown by in vitro and animal experiments. However, it is controversial whether the GPIIb/IIIa receptor facilitates tissue factor-induced thrombin generation in humans as well. We therefore investigated whether two clinically used GPIIb/IIIa antagonists (tirofiban and eptifibatide) may blunt TF-induced coagulation in humans.

Thirty male volunteers received 2 ng/kg endotoxin and standard doses of eptifibatide, tirofiban or placebo over 5 hours in a randomized, double-blind, placebo-controlled, double-dummy parallel-group trial. Markers of thrombin generation (prothrom-bin fragment 1+2, thrombin-antithrombin complexes), fibrinoly-sis (D-dimer, plasmin-antiplasmin complexes) as well as inflammatory markers (interleukin-6, tumor necrosis factor-α) were measured by enzyme linked immunoasssays, TF-mRNA expression was quantified by RT-PCR. Neither eptifibatide nor tirofiban influenced LPS-induced coagulation activation or fibrinolytic activity. Additionally, the increase of TNF-α and IL-6 was similar in all groups.

In conclusion, GPIIb/IIIa blockade with eptifibatide or tirofiban did not influence TF-induced coagulation activation in human low grade endotoxemia.
Low protein Z plasma levels are independently associated with acute coronary syndromes
Authors: Fedi Sandra , Brogi Daria , Tellini Irene , Cesari Francesca , Sestini Ilaria , Gazzini Alessandra , Comeglio Marco , Abbate Rosanna , Franco Gensini Gian , Sofi Francesco
Published: October 2003

Protein Z (PZ) is a single chain vitamin-K-dependent glycoprotein synthesized by the liver. Studies in vivo and in vitro suggest that PZ plays an important role in inhibiting coagulation as it serves as cofactor for the inactivation of factor Xa by forming a complex with the plasma PZ-dependent protease inhibitor. Recently, conflicting findings on plasma PZ levels in patients with ischemic stroke have been published.

Aim of our study was to investigate the role of PZ in acute coronary syndromes (ACS). PZ plasma levels were determined in 223 (189 M; 34 F) patients with ACS referring to the Coronary Intensive Therapy Unit of University of Florence and in 265 (219 M; 46 F) healthy subjects. Patients under oral anticoagulation treatment as well as subjects with positivity for antiphospholipid antibodies were excluded. None had liver or kidney dysfunction. The mean PZ plasma level was lower in patients (1508 ± 730 ng/mL) than in controls (1728 ± 594 ng/mL) (p < 0.0001). PZ levels below the 5th percentile (565 ng/mL) of normal values distribution in control subjects were found in 15.7% of patients and in 4.9% of controls (p <0 .0001). At multivariate analysis, PZ levels below 565 ng/mL were associated with ACS (OR=3.3; 99%CI 1.1-9.7; p = 0.004). The contemporary presence of low PZ levels and smoking habit leads to an increased risk of ACS (OR=9.5; 99%CI 2.4-37.2; p < 0.0001). In conclusion, our results suggest a possible role of PZ in the occurrence of arterial thrombosis.
Blood coagulation and fibrinolysis before and after exhaustive exercise in patients with IDDM
Authors: Eichler Evelyn , Gläser Doreen , Prasa Dagmar , Stürzebecher Jörg , Gabriel Holger , Hilberg Thomas
Published: October 2003

Diabetes mellitus involves changes in haemostasis which leads to the opinion that diabetes mellitus is a hypercoagulable state. However, little is known about the relationship of exercise and haemostasis in diabetics. Therefore, first of all the aim was to investigate if differences in blood coagulation and fibrinolysis can be demonstrated in subjects with insulin-dependent diabetes mellitus (IDDM) compared to controls and secondly, if differences concerning exercise induced changes can be seen in diabetics. 16 moderately fit subjects with IDDM and 16 matched controls underwent a maximal step test. Blood samples were taken after a 30 min rest, immediately and 1h after exercise and in addition after 30 min rest 7 days later at the same time of day. The rest values (mean of the two rest samples) in extrinsic total thrombin potential (TTPex, P=0.049), tPA-activity (P=0.007) were significantly higher and in PAI-1-antigen (P=0.002) -activity (P=0.049) lower in the diabetic group. APTT, PT, TAT (only control), TTPin, tPA-activity and -antigen and PAP were increased immediately and D-dimer (only control) 1 h after exercise, whereas PAI-1-activity and -antigen (only control) decreased immediately or 1 h after exercise (all minimal P<0.05). The increase of tPA-antigen and decrease in PAI-1-antigen after exercise were both lower in the diabetics (P<0.05).

IDDM led to higher extrinsic total thrombin and fibrinolytic potential at rest, and reducing the exercise provoked distribution of tPA-antigen and decrease of PAI-1-antigen. Nevertheless a higher thrombotic risk after maximal exercise has not been investigated in young IDDM patients without complications and in good metabolic control.
Severe prekallikrein (Fletcher factor) deficiency due to a compound heterozygosis (383Trp stop codon and Cys529Tyr)
Authors: Teresa Sartori Maria , Cabrio Laura , Fadin Mariangela , Zanon Ezio , Girolami Antonio , Maria Lombardi Anna
Published: October 2003

We investigated a family with prekallikrein deficiency, using both standard coagulation tests and molecular biology techniques. The propositus was found to be a compound heterozygote for a Trp383 stop codon and a Cys529Tyr point mutation. The former mutation was located in exon 11, the latter in exon 14. The propositus inherited the first defect from his father and the second from his mother. Both parents had slightly low prekallikrein levels, but the combination of the two genetic defects produced a phenotype characterized by an extremely low prekallikrein activity and antigen. The propositus’ plasma showed a progressive reduction in APTT when incubated for a long time. Conversely, plasma deficient in factor XII, factor XI or high molecular weight kininogen (HMWK) failed to show shortening of the APTT. No circulating anticoagulant was found because the patient’s APTT was fully corrected by pooled normal and factor XII-, factor XI- or HMWK deficient plasma. No associated abnormality was apparent in the propositus or his parents. As expected, no tendency for bleeding was noted even after tonsillectomy.
A microsatellite polymorphism in the heme oxygenase-1 gene promoter is associated with increased bilirubin and HDL levels but not with coronary artery disease
Authors: Schillinger Martin , Marculescu Rodrig , Sunder-Plassmann Raute , Raith Marianne , Jordanova Nelli , Wojta Johann , Mannhalter Christine , Huber Kurt , Endler Georg , Exner Markus , Wagner Oswald
Published: October 2003

Heme oxygenase 1 (HO-1) is involved in the generation of the endogenous anti-oxidant bilirubin which exerts beneficial effects against arteriosclerosis. A (GT) repeat polymorphism in the HO-1 promoter region modulates HO-1 expression in response to oxidative stress. Recently, this polymorphism has been reported to protect from coronary artery disease in Orientals. We intended to confirm this observation in Caucasians.

We studied 649 individuals with myocardial infarction (n=258), stable coronary artery disease (n=180) and controls without coronary artery disease (n=211). Carriers of short alleles (<25 repeats) had higher bilirubin levels (median 0.66 mg/dL, IQR 0.49 to 0.91) compared to non-carriers (median 0.61mg/dL, IQR 0.45 to 0.82; p=0.03) and a more favourable lipid profile (HDL median 47mg/dL, IQR 40 to 50 vs. median 45, IQR 37 to 55, p=0.01; triglycerides median 118mg/dL, IQR 87 to 174 vs. median 132, IQR 97 to 191, p=0.03). However, no significant differences of the genotype distribution were observed between the three groups in this Caucasian study population (p=0.94).

Although potentially beneficial effects of the short HO-1 allele on lipid profile and serum bilirubin were observed, in contrast to Orientals, the HO-1 genotype was not associated with coronary artery disease in Caucasians.
Regulatory roles of androgens in cutaneous wound healing
Authors: Gilliver Stephen , Wu Fred , Ashcroft Gillian
Published: October 2003

Although the effects of androgens on wound healing are poorly characterised, the androgen receptor is expressed by inflammatory cells, keratinocytes and fibroblasts during wound healing, suggesting that androgens may regulate inflammatory and/or repair processes. In fact, it appears that endogenous testosterone inhibits wound healing and promotes inflammation since castration of male mice or systemic treatment with the androgen receptor antagonist flutamide accelerates cutaneous wound healing and reduces the inflammatory response. The aim of this review is to summarise our current knowledge about the regulation of tissue repair processes by androgens.
Accumulation of radiolabelled platelets and fibrin on the carotid artery of rabbits after angioplasty: effects of heparin and dipyridamole
Authors: Lorenz Martin , Merk Herbert , Buchanan Michael , Eisert Wolfgang , van Ryn Joanne
Published: October 2003

We investigated the dynamic accumulation of platelets and fibrin after balloon injury of the carotid arteries in rabbits in vivo. In addition, effects of heparin and dipyridamole treatment were also tested. Autologous 99mTc-labelled platelet and 123I-labelled fibrin accumulation was measured at one minute intervals for 4 hours following balloon injury of the carotid artery. Platelet accumulation occurred rapidly, with a ~125% increase occurring within 30 min after injury. There was no further activity for up to 4 hours. This accumulation could be inhibited with an intravenous infusion of PGI2 (500 ng/kg/hr). Fibrin accumulation occurred slowly and continuously over the 4 hour measurement period. Injection of an anti-fibrin antibody inhibited fibrin accumulation. Heparin (25 U/kg/hr for 4 hrs) administration resulted in a significant 82 ± 19% and 68 ± 13% reduction in platelet and fibrin accumulation, respectively. This dose of heparin was associated with a 2-fold prolongation of the aPTT. Dipyridamole (0.45 mg/kg/hr for 4 hrs) resulted in a 46 ± 12% and 70 ± 25% reduction of platelet and fibrin accumulation, respectively. Thus, we demonstrated that the dynamics of platelet and fibrin accumulation following balloon injury in rabbits are very different. The vessel wall continues to be thrombogenic for fibrin up to 4 hours after injury even though platelet accumulation has ceased after one hour. We conclude that the local thrombotic events following balloon injury are complex and that not only platelets but also fibrin is important in regulating responses to injury.
High D-dimer levels predict cardiovascular events in patients with chronic atrial fibrillation during oral anticoagulant therapy
Authors: Mavri Alenka , Košmelj Katarina , Stegnar Mojca , Vene Nina
Published: October 2003

Atrial fibrillation (AF) is associated with hemostatic abnormalities and increased risk of thrombotic cardiovascular events even during oral anticoagulant therapy (OAT). The aim of our study was to evaluate the predictive value of hemostatic markers for the risk of major cardiovascular events during OAT. The study group comprised 113 patients with chronic AF (70.2 ± 5.4 years old, 60% men), referred for OAT. Established clinical risk factors and levels of prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complexes (TAT), D-dimer, tissue plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) antigen and activity, before and during OAT (after 3.9 ± 0.7 months; INR 2.57 ± 0.57) were determined. In all patients OAT significantly suppressed levels of F1+2 by 67%, TAT by 30% and D-dimer by 48% (all p <0.001). During an average follow-up of 44 months 22/111 (20%) patients suffered a combined cardiovascular event (stroke, myocardial infarction, peripheral vascular occlusion or vascular death). Patients with cardiovascular events were significantly older, had more frequent heart failure/systolic dysfunction and had significantly increased levels of D-dimer at entry (63 vs 39 ng/mL, p = 0.005) and during OAT (33 vs 18 ng/mL, p = 0.002), and of t-PA antigen at entry (14.3 vs 10.9 ng/mL, p = 0.02) and during OAT (15.0 vs 11.2 ng/mL, p = 0.05) (all values are medians). In multivariate Cox proportional hazard models, heart failure/systolic dysfunction (hazard ratio 2.91; 95% CI 1.17-7.26; p = 0.02), high levels of D-dimer on OAT (top vs. lower two quartiles) (hazard ratio 4.78, 95% CI 1.39-16.41; p = 0.01) and t-PA antigen levels (continuous variable) (hazard ratio 1.09; 95% CI 1.01-1.17; p = 0.02) were significantly associated with combined cardiovascular events.

In conclusion, high levels of D-dimer and t-PA antigen during OAT are significant predictors of combined cardiovascular events in AF patients and, on this basis, could be useful additional markers of cardiovascular risk in such patients.
Cost-effectiveness of two models of management for patients on chronic warfarin therapy – a Markov model analysis
Authors: Chan Fredric , Wong Raymond , Cheng Gregory , You Joyce
Published: October 2003

Allocation of additional resources for establishing or expanding anticoagulation clinic (AC) services is a significant concern for healthcare decision-makers when the payer is also the provider of the healthcare system. The majority of anticoagulated patients in Hong Kong are managed by routine medical care (RMC) instead of ACs, possibly due to the lack of local cost-effectiveness analysis of the AC setting. The aim was to compare the clinical and economic outcomes of anticoagulated patients who were managed by AC or RMC from the perspective of a public health organization in Hong Kong. A Markov model was designed to simulate, over 10 years, the economic and clinical outcomes of patients receiving chronic warfarin therapy managed by AC or RMC. The transition probabilities were derived from literature. Resource utilization was retrieved from patients managed by AC and RMC in Hong Kong. Sensitivity analysis was conducted to examine the robustness of the model. The total number of events per 100 patient-years and the direct medical cost per patient-year in the AC and RMC groups were 9.5 and USD 840, and, 19.3 and USD 1,179, respectively. The results of the model were sensitive to the variation of the probability of major bleeding in the AC group. In conclusion, the coordinated care provided by an anticoagulation clinic appears to be more cost-effective than routine medical care in the management of warfarin therapy from the perspective of public health organization in Hong Kong.
Animal models of vulnerable plaque
Authors: Jang Ik-Kyung , Khachigian Levon , Lowe Harry
Published: October 2003

There is increasing recognition of the importance of vulnerable plaque and acute plaque rupture leading to thrombosis, in the pathogenesis of acute coronary syndromes. This is fueling a number of developments, including novel imaging modalities and potential plaque stabilization therapies. However, to date, no animal model of vulnerable plaque or plaque rupture has been established. Recent developments, particularly using Apo E knockout mice, appear set to provide key breakthroughs. The present status of our understanding of plaque vulnerability is therefore discussed, with a discussion of these current advances in animal models.
Antithrombin reduces the ischemia/reperfusion-induced spinal cord injury in rats by attenuating inflammatory responses
Authors: Hirose Koji , Taoka Yuji , Uchiba Mitsuhiro , Nakano Kan-yu , Utoh Junichi , Kitamura Nobuo , Okajima Kenji
Published: October 2003

Antithrombin (AT) reveals its antiinflammatory activity by promoting endothelial release of prostacyclin (PGI2) in vivo. Since neuroinflammation is critically involved in the development of ischemia/reperfusion (I/R)-induced spinal cord injury (SCI), it is possible that AT reduces the I/R-induced SCI by attenuating the inflammatory responses. We examined this possibility using rat model of I/R-induced SCI in the present study. AT significantly reduced the mortality and motor disturbances by inhibiting reduction of the number of motor neurons in animals subjected to SCI. Microinfarctions of the spinal cord seen after reperfusion were markedly reduced by AT. AT significantly enhanced the I/R-induced increases in spinal cord tissue levels of 6-keto-PGF1α, a stable metabolite of PGI2. AT significantly inhibited the I/R-induced increases in spinal cord tissue levels of TNF-α, rat interleukin-8 and myeloperoxidase. In contrast,Trp49-modified AT did not show any protective effects. Pretreatment with indomethacin significantly reversed the protective effects of AT.An inactive derivative of factor Xa, which selectively inhibits thrombin generation, has been shown to fail to reduce SCI.Taken together, these observations strongly suggested that AT might reduce I/R-induced SCI mainly by the antiinflammatory effect through promotion of endothelial production of PGI2. These findings also suggested that AT might be a potential neuroprotective agent.
Evaluation of ADAMTS-13 activity in plasma using recombinant von Willebrand Factor A2 domain polypeptide as substrate
Authors: Whitelock Jody , Dong Jing-fei , Cruz Miguel
Published: October 2003

The metalloprotease ADAMTS-13 cleaves von Willebrand factor (VWF), and is absent or severely reduced in the plasma of patients with thrombotic thrombocytopenia purpura (TTP). Under physiologic flowing conditions, the enzyme cleaves endothelial cell-derived ultra-large VWF multimers at the Y842/M843 peptide bond located in the A2 domain, where many mutations associated with Type 2A VWD cluster. These VWF mutants are more susceptible for cleavage activity, decreasing the large VWF multimers in the plasma. The susceptibility of a recombinant VWF-A2 domain to ADAMTS-13 and the potential application in detecting enzyme activity were investigated. In vitro, fluid phase cleavage of VWF by ADAMTS-13 requires denaturing conditions and prolonged incubation in order to estimate enzyme activity. We have measured ADAMTS-13 activity based on enzyme cleavage of a recombinant VWF-A2 domain under non-denaturing conditions. In our assay, enzyme activity was absent in plasma from congenital and acquired TTP patient, and blocked by each EDTA, monoclonal antibody VP-1 (peptide-specific antibody against residues 828-842 of VWF), and an ADAMTS-13 antibody purified from plasma of an acquired TTP patient. This novel recombinant VWF-A2 protein has potential utility as matrix for a rapid clinical measurement of plasma ADAMTS-13 activity.