bluuebunny/crossref_metadata_2025 huggingface dataset:
Platelet Interaction with Vessel Wall and Collagen in Pigs with Homozygous von Willebrand’s Disease Associated with Abnormal Collagen Aggregation
Authors: Badimon L , Badimon J J , Galvez A , Turitto V , Fuster V
Published: July 2018

A subgroup of pigs with von Willebrand’s disease from the Mayo Clinic stock shows abnormal platelet aggregation in response to collagen [vWD-Homo(-)], in contrast to the normal aggregation responses observed in the main colony of pigs with homozygous vWD [vWD-Homo(+)]. This subgroup has been characterized at Mayo as a storage pool deficiency due to the reduced levels of ADP and Serotonin in the platelet dense granules. In the present studies, an ex-vivo perfusion chamber was utilized to investigate the deposition of 111In-labeled platelets on aortic subendothelium and collagen type I exposed to blood from vWD-Homo(-), vWD-Homo(+) and normal animals. Both non-anticoagulated and heparinized blood were exposed for wall shear rates ranging from 212 sec-1 to 3380 sec-1 and exposure times as long as 30 min. An enhanced decrease in platelet deposition in the vWD-Homo(-) animals was observed compared to vWD-Homo(+) animals. The decrease was observed primarily at the higher shear rates and was more pronounced in the absence of heparin and on the collagenous substrate. Thus, the abnormality in collagen-induced aggregation, which has been characterized as a storage-pool type defect, results in a decreased platelet deposition compared with that produced by severe vWD alone.
Hypercoagulable State in the Watanabe Heritable Hyperlipidemic Rabbit, an Animal Model for the Progression of Atherosclerosis
Authors: Mori Yoshitaka , Wada Hideo , Nagano Yutaka , Deguch Katsumi , Kita Toru , Shirakawa Shigeru
Published: July 2018

Blood coagulation in a strain of rabbits designated as Watanabe heritable hyperlipidemic (WHHL) rabbits was examined. The activities of vitamin K-dependent clotting factors, contact factors and clotting factor VIII (F VIII) and the fibrinogen level were significantly higher in WHHL rabbits than in normolipidemic rabbits (all age groups). Values for vitamin Independent clotting factor were already higher at 2 months of age. Contact factors and fibrinogen levels increased age after 5 to 8 months. F VIII increased between 5 and 8 months and then decreased. At 2 months of age, WHHL rabbits were divided into two groups. Group A was fed standard rabbit chow and group B standard rabbit chow containing 1% probucol. Probucol prevented the progression of atherosclerosis in group B in the absence of a significant reduction in plasma cholesterol level. F VIII and fibrinogen levels were statistically decreased in all rabbits at all ages in group B (P<0.05). These differences in clotting factors between the two groups were most obvious at 8 months (P<0.02).

We conclude that vitamin K-dependent clotting factors may increase with hyperlipemia and that increases in F VIII and fibrinogen may be closely related to the progression of throm- boatherosclerosis.
The Use of DNA Amplification for Genetic Counselling Related Diagnosis in Haemophilia B
Authors: Tsang T C , Bentley D R , Nilsson I M , Giannelli F
Published: July 2018

A single base pair variation in the coding sequence of
coagulation factor IX produces a protein polymorphism detectable with monoclonal antibodies and a restriction fragment length polymorphism (RFLP). This allows carrier and prenatal diagnoses in 48% of Caucasian families segregating for haemophilia B. However, this RFLP cannot be detected by standard Southern blotting, while the antibody assay may grve equivocal results in some females and can only allow prenatal diagnoses on second trimester fetal blood samples. We show that, using the polymerase chain reaction, the polymorphic DNA segment can be amplified and directly tested for the presence of the alternative sequences by a non-radioactive procedure that has the advantage of speed (1–2 days), partial automation and applicability to first trimester diagnoses. We also show that the method gives results on a single drop of dried blood.
Unfractionated Heparin and CY 216: Pharmacokinetics and Bioavailabilities of the Antifactor Xa and IIa Effects after lntravenous and Subcutaneous Injection in the Rabbit
Authors: Briant L , Caranobe C , Saivin S , Sié P , Bayrou B , Houin G , Boneu B
Published: July 2018

This report compares the pharmacokinetics and the bioavailabilities of the antifactor Xa and of the antifactor II a activities generated by intravenous (IV) and subcutaneous (SC) injections of increasing doses of unfractionated heparin (UH) and of a low molecular weight heparin (CY 216). Rabbits were injected with 500, 1,000, 2,500 and 5,000 antifactor Xa u/kg of both heparins and their biological activities were followed at various time intervals. After IV injection the clearance of the antifactor Xa activities was independent of the dose and the clearance of UH was significantly higher than that of CY 216; after SC injection the bioavailability estimated from the antifactor Xa effect was consistently over 100% for CY 216 while that of UH increased from 27% at the lowest dose to 93% at the highest dose. The pharmacokinetic parameters estimated by the antifactor IIa activity of UH were superimposable to those calculated with the antifactor Xa activity. For CY 216 no direct comparison between the two activities was made since the dose injected expressed in antifactor IIa units was 3.4 times lower. UH and CY 216 were therefore injected intravenously to other animals at equivalent and increasing doses expressed in antifactor IIa units (50-5,000 u/kg). The pharmacokinetic parameters calculated from the curves of the antifactor IIa activities were basically identical except at the two lower doses (50 and 100 u/kg) for which UH was cleared faster than CY 216. These results indicate that the antifactor IIa activity generated by an injection of CY 216 disappears faster than the corresponding antifactor Xa activity and therefore that the antifactor Xa/antifactor IIa activity ratio of CY 216 progressively increases after SC or IV injection.
Platelet and Shear Rate Promote Tumor Cell Adhesion to Human Endothelial Extracellular Matrix - Absence of a Role for Platelet Cyclooxygenase
Authors: Bastida Eva , Almirall Lourdes , Ordinas Antonio
Published: July 2018

Blood platelets are thought to be involved in certain aspects of malignant dissemination. To study the role of platelets in tumor cell adherence to vascular endothelium we performed studies under static and flow conditions, measuring tumor cell adhesion in the absence or presence of platelets. We used highly metastatic human adenocarcinoma cells of the lung, cultured human umbilical vein endothelial cells (ECs) and extracellular matrices (ECM) prepared from confluent EC monolayers. Our results indicated that under static conditions platelets do not significantly increase tumor cell adhesion to either intact ECs or to exposed ECM. Conversely, the studies performed under flow conditions using the flat chamber perfusion system indicated that the presence of 2 × 105 pl/μl in the perfusate significantly increased the number of tumor cells adhered to ECM, and that this effect was shear rate dependent. The maximal values of tumor cell adhesion were obtained, in presence of platelets, at a shear rate of 1,300 sec-1. Furthermore, our results with ASA-treated platelets suggest that the role of platelets in enhancing tumor cell adhesion to ECM is independent of the activation of the platelet cyclooxygenase pathway.
ADP-Induced Platelet Aggregation as a Function of Age in Healthy Humans
Authors: Vilén L , Jacobsson S , Wadenvik H , Kutti J
Published: July 2018

In 120 healthy humans (58 males and 62 females) possible differences in platelet aggregability were investigated with respect to age and sex. By using a narrow range of final ADP concentrations (0.2-1.0 μM) primary and secondary aggregation were evaluated. The rate of primary aggregation was shown to be significantly related to increasing age and this was true for both sexes.

As regards secondary aggregation the same pattern was seen in the group of male subjects. Thus, among the youngest (<34 years) the frequency of secondary waves was only one third of that encountered among the oldest (>50 years). No similar association was detectable among the female subjects.

The present study calls attention to some important issues which should be considered in platelet aggregation studies; the interpretation of data obtained from such studies invariably requires a careful selection of appropriate age- as well as sex-matched control groups.
The Frequency of Bleeding and Height of Adolescent Haemophiliacs
Authors: Bem J L , Painter M J , Aronstam A , Patrick J H , Newcombe R E
Published: July 2018

The relation between the height of adolescent haemophiliacs and their bleeding frequency has been studied. 45 haemophiliacs aged 10-19 years were divided into 3 groups: small, medium and tall, using a Height Standard Deviation Score. The average bleeding frequency per 100 days in the group of small haemophiliacs was 8.71 ± SD 4.47, in the medium height group 10.18 ± SD 6.71, while the tall individuals bled in average 15.97 ± SD 3.15 every 100 days. There was no relationship between age and bleeding frequency.
Human Platelets Contain mRNA Transcripts for Platelet Factor 4 and Actin
Authors: Sottile Jane , Mosher Deane F , Fullenweider Jan , George James N
Published: July 2018

RNAs from a number of cells, including platelets, were analyzed by Northern blotting for the presence of transcripts to four platelet proteins - actin, thrombospondin, fibronectin, and platelet factor 4. RNA from platelets contains considerable amounts of mRNA for platelet factor 4, easily detectable mRNA for actin, and traces of mRNA for thrombospondin. mRNA for platelet factor 4 was not detected in human lymphocytes or in any of 5 human cell lines.
Evaluation of the Binding to Fixed Platelets of Agonists and Antagonists of ADP-Induced Aggregation
Authors: Agarwal Ashok K , Tandon Narendra N , Greco Nicholas J , Cusack Noel J , Jamieson G A
Published: July 2018

Steady state binding of eleven different ADP analogues to formaldehyde-fixed platelets has been determined in a competitive binding assay using 3H-ADP. The compounds tested were the inactive analogues L-ADP and L-ATP; the agonists 2-chloroadenosine 5’-diphosphate, adenosine 5’-O-(2-thiodiphosphate)and the diastereoisomeric pair Sp-adenosine 5’-(1-thiodiphosphate) (Sp-ADP-α-S) and Rp-adenosine 5’-(1-thiodiphosphate) (Rp-ADP-α-S); and the antagonists adenosine 5’-O-thiomonophosphate, 2-chloroadenosine 5’-O-thiomonophosphate, 2-chloroadenosine 5’-triphoshate, and the diastereoisomeric pair 5’-(1-thiotriphosphate) (Sp-ATP-α-S) and Rp-adenosine 5’-(1-thiotriphosphate) (Rp-ATP-α-S). All compounds tested competed at the high affinity binding sites for ADP previously identified (Blood 1988; 71: 110-6) but in some cases competition could not be demonstrated at the low affinity sites because of the high nucleotide concentrations required. As a group, C2-substituted analogues bound less strongly (Ki >2 μM) than did the analogues without substituents in the purine ring (Ki <0.7 μM). With the pair of diastereoisomeric agonists Sp-ADP-α-S and Rp-ADP-α-S the Ki values at the high affinity site (210 nM and 560 nM) were of the same relative magnitude and in the same direction as their reported potencies as agonists (Ki 4 μM and 20 μM). With the diastereoisomeric antagonists Sp-ATP-α-S and Rp-ATP-α-S a similar relationship was seen between affinity (17 nM and 156 nM) and inhibitory potency (Ki 4 μM and 20 μM). These results may help to differentiate possible mechanisms in the interaction of ADP with its receptors.
Asialo von Willebrand Factor Enhances Platelet Adhesion to Vessel Subendothelium
Authors: Bastida Eva , Monteagudo Juan , Ordinas Antonio , Marco Luigi De , Castillo Ricardo
Published: July 2018

Native von Willebrand factor (N-vWF) binds to platelets activated by thrombin, ADP or ristocetin. Asialo vWF (As-vWF) induces platelet aggregation in absence of platelet activators. N-vWF mediates platelet adhesion to vessel subendothelium at high shear rates. We have investigated the role of As-vWF in supporting platelet deposition to rabbit vessel subendothelium at a shear rate of 2,000 sec-1, using the Baumgartner perfusion system. We have studied the effects of the addition of As-vWF (from 2 to 12 μg/ml) to perfusates consisting of washed red blood cells, 4% human albumin and washed platelets. Our results show a significant increase in platelet deposition on subendothelium (p <0.01) in perfusions to which As-vWF had been added. Blockage of the platelet glycoproteins Ib and IIb/IIIa (GPIb and GPIIb/IIIa) by specific monoclonal antibodies (LJIb1 and LJCP8, respectively) resulted in a decrease of platelet deposition in both types of perfusates prepared with N-vWF and As-vWF. Our results indicate that As-vWF enhances platelet deposition to vessel subendothelium under flow conditions. Furthermore, they suggest that this effect is mediated by the binding of As-vWF to platelet membrane receptors, which in turn, promote platelet spreading and adhesion to the subendothelium.
Fibrinogen Nijmegen : Congenital Dysfibrinogenemia Associated with Impaired t-PA Mediated Plasminogen Activation and Decreased Binding of t-PA
Authors: Engesser Luzia , Koopman Jaap , Munk Gé de , Haverkate Frits , Novéková Irena , Verheijen Jan H , Briët Ernest , Brommer Emile J P
Published: July 2018

Congenital dysfibrinogenemia was found in a patient with venous thrombosis. Blood clot lysis was prolonged and suggested an impairment of fibrinolysis. We investigated whether this was related to the fibrinogen abormality. Fibrinopeptide release was normal but fibrin polymerization was defective in the patient. The stimulating effect of the patient’s fibrin on t-PA mediated plasminogen activation was impaired. This could not be attributed to defective binding of plasminogen. However, the binding of t-PA to the patient’s fibrin was about 16% less than to normal fibrin. A variant t-PA (G K1 K2 P), which contained only one of the two fibrin binding sites, i.e. the kringle-2 domain, was bound to the abnormal fibrin for only 50% of normal.

We conclude that the prolongation of blood clot lysis and the impaired stimulation of t-PA mediated plasminogen activation are related to the defective binding of the kringle-2 domain of t-PA onto the fibrin moiety of the abnormal fibrinogen. The impairment of fibrinolysis might explain the occurrence of throm-bosis in the patient.
The Active Serotonin Uptake and the Hypotonic Shock Response of Human Blood Platelets
Authors: Hardeman M. R , Heynens Carina J. L.
Published: July 2018

The present paper is part of a study on the evaluation of the active serotonin uptake and the response to hypotonic shock as in vitro viability tests for human blood platelets.

The extraction and fluorometric assay of serotonin in plasma and in platelets were further automated by the introduction of a dialyzer in the earlier described system. Furthermore, the influences of some external factors on both tests were investigated.

The serotonin uptake as well as the hypotonic shock response were pH dependent and especially the latter was rather sensitive to small pH changes. Changes in the Na+ : K+ ratio were also found to influence both criteria significantly.

The serotonin uptake appeared to be linearly dependent on the platelet number while, within a range of 200 X 103 - 450 X 103 platelets per fxl, the slope of the hypotonic shock response was the same.
Sensitive Methods for the Detection and Characterization of Platelet Isoantibodies
Authors: Hirschman Richard J. , Yankee Ronald A. , Coller Barry S. , Gralnick Harvey R.
Published: July 2018

Two sensitive methods for the detection and characterization of platelet isoantibodies are presented in this paper. The methods involve incubating platelets with either radioactive serotonin or adenine, interaction of the platelets with serum antibody and finally detection of supernatant radioactivity. Both tests can be used for HL-A typing of platelets and both tests detect antibodies undetectable by complement fixation. The requirement of a heat labile serum component is variable in the serotonin test but absolute in the adenine test. Antibody activity was found to be in the 7S gamma globulin fraction on DEAE cellulose column chromatography.
On the Mechanism by which Bovine Fibrinogen Induces the Release and Availability Reaction of Human Blood Platelets
Authors: Kubisz P , Suranová J
Published: July 2018

Bovine fibrinogen can aggregate human blood platelets by a direct mechanism (first wave) and also indirectly by releasing endogenous ADP (second wave).

A primarily non-altered surface structure of the thrombocytes is important for the induction of the first wave.

Under certain conditions a second aggregation wave, concomitant with the release and the availability reaction is elicited.

Besides the cells’ contact, the presence of ADP and calcium ions are necessary for the induction of the release reaction in human platelet rich plasma.

The changes induced by bovine fibrinogen thus follow the same pattern as the irreversible phase of aggregation, linked to release as induced by ADP.
Platelet Thrombosis and Non-traumatic Intimal Injury in Mouse Aorta
Authors: Jørgensen Leif , Hærem Jørgen W. , Moe Narve
Published: July 2018

Aortas of mice, not exposed to any experimental injury, were examined by light and electron microscopy for the initial stages of mural thrombosis.

Platelets in the lumen frequently formed groups or loose platelet aggregates. Individual platelets and platelet aggregates, both loose and dense, were often in contact with the inner vascular lining in focal areas. The underlying intimal tissue, including the endothelial cells, showed varying degrees of injury. Occasionally, however, platelet material was in contact even with structurally normal endothelial cells. The platelet- endothelial cell contact appeared to be an expression of adherence.

Small mural thrombi were less frequently observed. They comprised platelets and fibrin and were mostly attached to subendothelial structures. Underneath the mural thrombi, the internal elastic membrane was often ruptured.

The observed phenomena fit best with the theory that the primary event in mural thrombosis in aorta of mice is platelet aggregation under the influence of local flow irregularities. The next steps could be adherence of platelets to the vessel wall and injury of the intimai tissue through the release of vasodestructive agents from the platelets. Through this injury a focus of mural thrombosis could be established.
Clotting Mechanisms in Patients with Hypertriglyceridemia during Therapy with Anabolic or Progestational Drugs
Authors: Glueck Helen I. , Glueck Charles J.
Published: July 2018

Effects of synthetic steroids with progestational and androgenic-anabolic activity (Norethindrone Acetate and Oxandrolone) on coagulation parameters and plasma lipids were studied in 20 patients with familial types III, IV and V hyperlipoproteinemia. Prior to therapy there was a relatively uniform elevation of fibrinogen (284 mg %) and esterase prothrombin (64 U/ml). On therapy mean fibrinogen fell sharply to 223 mg % (short-term) and 195 mg % long-term. There were no increments in other clotting factors, and levels of factor VII and X were decreased on drug in several patients who initially had abnormally high levels. The fall in fibrinogen on therapy did not correlate with concurrent decrements in cholesterol or triglyceride. In hypertriglyceridemic patients predisposed to coronary or peripheral vascular thrombosis, Norethindrone and Oxandrolone appear to ameliorate rather than potentiate any tendency to “hypercoagulability”.
Streptokinase Stability Pattern during Storage in Various Solvents and at Different Temperatures
Authors: Martin M , Auel Fräulein H ,   Technical assistance
Published: July 2018

The activity drop of 5 u streptokinase was measured in 1 ml each of various solutions (0.9% NaCl solution, 5% glucose solution, 5% levulose solution, 10% dextran solution, gelatin solution, 3% albumin solution, Michaelis buffer, glucose (5%)-heparin (750 u/ml) solution) at different incubation temperatures (–20° c, 4° c, 20 c, 37 C), and over different observation periods (15 min, 30 min, 45 min, 60 min, 6 h, 12 h, 24 h, and 48 h). Solution media tested for streptokinase-protecting quality were broken down into three groups.

Group I: Solvents displaying excellent stabilizing properties (gelatin and albumin solutions).

Group II: Solvents displaying medium stabilizing properties (dextran and levulose solutions).

Group III: Solvents displaying poor stabilizing properties (NaCl and glucose solutions, Michaelis buffer).

In testing streptokinase concentrations as used for therapeutic purposes (1500 u/ml, 50,000 u/ml), no decay was found to take place over observation periods of up to 48 h, and no influence by different solvents (Group I, II or III) was traceable. Heparin stored with streptokinase at room temperature over a period of 48 h did not alter the streptokinase stability.

Some mechanisms concerning the stability pattern of streptokinase are discussed. It appears that low streptokinase concentrations need negatively charged colloids to keep the protein structure intact. The streptokinase-protecting macro-molecules tested so far were albumin, gelatin, and streptokinase. Obviously, streptokinase by itself was able to preserve its own stability provided its concentration was of a certain order of magnitude (1500 u/ml, 50,000 u/ml).
Scanning Electron Microscopic and Electrophoretic Observations on Barium Sulphate Used to Adsorb Clotting Factors
Authors: Howell R. M , Deacon S. L. M
Published: July 2018

Electron microscopy and particle electrophoresis were found to be complementary techniques with which to complete the physical data from an earlier study on barium sulphates used to adsorb clotting factors from serum. The differences revealed by scanning electron microscopy (S. E. M.) in the physical shape of low and high density grades of barium sulphate particles appear to be of greater significance than charge as expressed by electrophoretic mobility, in determining whether or not precursor or preformed factor Xa is eluted.

This conclusion was based on the finding that at pH values close to 7, where the adsorption from serum occurs, all samples with the exception of natural barytes were uncharged. However as the high-density, or soil-grade, was found by S. E. M. to consist of large solid crystals it was suggested that this shape might induce activation of factor X as a result of partial denaturation and consequent unfolding of the adsorbed protein. In contrast, uptake of protein into the centre of the porous aggregates revealed by S. E. M. pictures of low-density or X-ray grade barium sulphate may afford protection against denaturation and exposure of the enzyme site.

The porous nature of particles of low-density barium sulphate compared with the solid crystalline forms of other grades accounts not only for its lower bulk density but also for its greater surface/gram ratio which is reflected by an ability to adsorb more protein from serum.

Neither technique produced evidence from any of the samples to indicate the presence of stabilising agents sometimes used to coat particles in barium meals.
Studies on Activator Formation in Human Plasma with Streptokinase
Authors: Martin M , Auel Miss H ,   Technical Assistance
Published: July 2018

A new method is presented for estimating the activator (plasminogen-streptokinase complex) concentration in native plasma of patients undergoing streptokinase infusion. The principle of the method is based on clot lysis time as recorded by the thromboelastograph. The test clot constituents were bovine fibrinogen, bovine plasminogen, EDTA, human plasma (with unknown activator concentrations), and thrombin. In order to obtain a standardization line, urokinase dissolved in NaCl solution was substituted for patients’ plasma. Thus, each lysis time could easily be converted into urokinase equivalent (CTA-u/ml). Streptokinase and plasminogen molecules in undiluted patients’ plasma were found to exist both in an activator-bound (equimolar plasminogen-streptokinase complex) and in a freely circulating form. This result is in agreement with earlier findings where the activator complex was demonstrated to be a widely dissociated complex in highly diluted plasma of patients, thus displaying an ample proportion of free streptokinase and plasminogen molecules. Streptokinase treatment using dosage schemes of 100,000 u SK/h, 150,000 u/h, and 200,000 u/h were monitored by quantitative activator, streptokinase, and plasminogen measurements. An average activator concentration of 50–100 CTA-u/ml and a SK-concentration of 7–16 u/ml were recorded during streptokinase infusion. Plasminogen values averaged 0.25%, independent of the amount of streptokinase infused. Each drop in streptokinase was accompanied by a drop in activator during the infusion, and each rise in streptokinase by a rise in activator. There was a strong correlation between streptokinase and activator concentrations in that, on the average, 1 u streptokinase equalled 8.4 CTA-u/ml activator (correlation coefficient r = 0.9). It is concluded that the activator concentration in the plasma of patients undergoing fibrinolytic treatment can easily be adjusted by regulating the hourly streptokinase influx.
The in Vitro Effects of Mithramycin on the Aggregation and the Calcium Uptake of Human Platelets
Authors: Chao Francis C. , Tullis James L.
Published: July 2018

The in vitro incubation of platelets with mithramycin caused a biphasic effect on ADP-induced aggregation. At a low dose of 10 [xg/ml, mithramycin caused an enhancement of aggregation whereas at high doses above 50 [μg/ml, it produced variable effects on aggregation with inhibition predominating. Effects on ADP-induced aggregation similar to those caused by mithramycin were produced by the simple addition of CaCl2 solution to the plasma medium. Mithramycin in the range which increased aggregation altered neither the whole blood clotting times nor the ionic calcium concentrations, but did increase the uptake of radioactive calcium by platelets. The results confirmed the in vivo observations that mithramycin treatment during tumor chemotherapy may directly alter the aggregation response of circulating platelets to ADP. The effects of mithramycin on aggregation may be mediated by alteration of calcium influx in normal platelets.
Contrast Venography, the Gold Standard for the Diagnosis of Deep-Vein Thrombosis: lmprovement in Observer Agreement
Authors: Lensing Anthonie W A , Büller Harry R , prandoni Paolo , Batchelor David , Molenaar Andre H M , Cogo Alberto , Vigo Mario , Huisman Peter M , ten Cate Jan Woutert
Published: July 2018

To determine whether the Rabinov-Paulin or the long-leg venography technique should be preferred in the diagnostic management of patients with clinically suspected deep-vein thrombosis, two independent experienced radiologists blindly assessed two different series of venograms of consecutive outpatients with clinically suspected deep-vein thrombosis. Venograms were obtained from two outpatient clinics of primary referral centres. In one centre the venograms were performed according to the technique of Rabinov and Paulin with the use of 100 ml of radiographic material and spot films of the calf, popliteal and more proximal veins. In the other centre, long-leg films were obtained after the administration of 150 ml of contrast material. The percentage venograms adjudicated as inadequate by at least one radiologist and inter-observer disagreement for both series were used as the main study outcome measures. Prior to the study, both radiologists agreed on the standardized criteria for a normal, abnormal and inadequate test result using a separate set of films.

An inadequacy rate of 20% was found for the Rabinov-Paulin venography series (n = 123), whereas only 2% of the L26long-leg films were inadequate for interpretation (p <0.001). The interobserver disagreement for inadequacy, presence or absence of deep-vein thrombosis was 2I% for the Rabinov and Paulin venograms and 4o/" for the long-leg films (kappa, 0.65 and 0.92; 95% confidence intervals: 0.53 to 0.77 and 0.84 to 0.99, respectively; p <0.002).

We conclude that the long-leg method is superior to the Rabinov-Paulin method in the venographic diagnosis of deep-vein thrombosis in symptomatic outpatients since noninterpretable test results are rarely observed and it reduces both unnecessary treatment of patients without deep-vein thrombosis and limits the undertreatment of patients with the disease.
No Evidence of HIV-1 Infection in Seronegative Hemophiliacs and in Seronegative Partners of Seropositive Hemophiliacs through Polymerase Chain Reaction (PCR) and Anti-NEF Serology
Authors: Ferrer-Le-Coeur Françoise , Mariotti Martine , Hivert Philippe , Satre Eric Pascal , Bouchardeau Françoise , Couroucé Anne-Marie , Rouger Philippe , Lefrère Jean-Jacques
Published: July 2018

We prospectively studied a well-characterized cohort including 60 seronegative hemophiliacs or von Willebrand’s disease patients, 6 seronegative female sexual partners of seropositive hemophiliacs, 59 seropositive hemophiliacs or von Willebrand’s disease patients and 2 seropositive partners of seropositive hemophiliacs (used as positive controls), and 117 seronegative low risk individuals (used as negative controls). PCR assay, performed in peripheral blood mononuclear cells using three primer pairs in the gag, pol, LTR regions, showed no positive results in the 60 seronegative patients, in the 6 seronegative partners of seropositive patients and in the 117 seronegative low risk individuals, while PCR was positive with at least one primer pair in 53 (87%) of 61 seropositive patients. Anti-nef serology (Westem-blot) was negative in seronegative patients, in seronegative partners of seropositive patients and positive in 58% out of the seropositive individuals. These results strongly suggest an absence of HIV-1 infection in individuals with a lastingly negative HIV serology.
Studies on the Contact System of Coagulation during Therapy with High Doses of Recombinant IL-2: Implications for Septic Shock
Authors: Hack C Erik , Wagstaff John , Strack Van Schijndel Robert J M , Eerenberg Anke J M , Pinedo Herbert M , Thijs Lambertus G , Nuijens Jan H
Published: July 2018

Patients treated with high doses of interleukin-2 (IL-2) because of cancer, develop hemodynamic and vasopermeability changes, that resemble those observed in sepsis. These patients thus provide a unique opportunity to study the early events in the development of septic shock. We analysed the changes that occurred in the contact system of coagulation in plasma from 4 patients, who together received seven 12-day cycles of high doses of IL-2. Levels of factor XII and prekallikrein during the cycles progressively fell to 50 and 30% of their initial levels, respectively, whereas significant increases in plasma factor XIIa-and kallikrein-C1-inhibitor complexes were not observed (in 3 out of 211 samples slightly increased levels of both complexes were found). The reductions in factor XII and prekallikrein were only in part due to protein leakage, since levels were still significantly lower, i. e., 80 and 50%, respectively, when corrected for albumin decreases. Levels of high molecular weight kininogen (HMWK) also decreased during IL-2 therapy, however, this decrease paralleled that of albumin. SDS-PAGE analysis of plasma HMWK did not reveal increased cleavage of this protein. The reduction of factor XII and prekallikrein, corrected for protein leakage, significantly correlated with albumin levels and inversely with daily cumulative weight gain in the patients.

Thus, we demonstrate that factor XII and prekallikrein decrease during IL-2 therapy. As these decreases, already observed after 1 day treatment, were disproportional to that of albumin, a negative acute phase reactant, and correlated with signs of the vascular leak syndrome, we favor the explanation that they reflected activation rather than a decreased synthesis of the contact system proteins. Further studies are needed to substantiate this hypothesis.
Evaluation of Pulmonary Accumulation of 51Chromium-Labelled Rat Platelets following Intravenous Application of ADP and Collagen
Authors: Klee Andreas , Seiffge Dirk
Published: July 2018

We examined the effects of ADP- and collagen-induced pulmonary platelet embolism in the rat. Homologous 51Chromium-labelled platelets were used to monitor extracorporally the distribution of platelets in the circulation. For that purpose, collimated iodide scintillation detectors were placed above thorax (C1) and abdomen (C2). A dose-dependent increase in thoracic radioactivity, paralleled by a decrease in the abdomen, was observed after intravenous injection of ADP and collagen. This resulted in a shift of C1/C2, so that the effect of collagen was more pronounced (maximal increase of C1/C2 = 134%) than ADP (maximal increase of C1/C2 = 79%). The increase in thoracic radioactivity was caused by the uptake of platelets in the lung as was shown after administration of collagen (6-fold enrichment of labelled platelets). Lung platelet sequestration resulted in a dose-dependent thrombocytopenia. The ADP-and collagen-induced pulmonary platelet embolism reversibly provoked cardiovascular symptoms of shock: hypotension and bradycardia. Impaired gas exchange during platelet accumulation manifested itself in a reversible arterial hypoxaemia and hyper-capnia, followed by a weak acidosis. We were able to inhibit ADP-dependent thoracic platelet accumulation by ticlopidine in a dose-related manner as well as collagen-induced thoracic platelet accumulation by acetylsalicylic acid. The results indicate that behaviour of homologous labelled rat platelets in vivo can easily be monitored, thus offering the opportunity to investigate the effects of antiaggregatory drugs on platelets in their natural environment.
Soluble Thrombomodulin Antigen in Conditioned Medium Is Increased by Damage of Endothelial Cells
Authors: Ishii Hidemi , Uchiyama Hiroyuki , Kazama Mutsuyoshi
Published: July 2018

Thrombomodulin (TM) exists not only in endothelial cells but also in circulating plasma as soluble heterogeneous fragments. A release mechanism of soluble TM antigen from endothelial cells was investigated. Cultured human umbilical vein endothelial cells released about 0.6% of total cellular TM antigen into conditioned medium during 24 h. The release of TM antigen was not influenced by addition of various concentrations (0.01-5.0 μM) of monensin, which inhibits intracellular transport of secretory proteins, though the secretion of plasminogen activator inhibitor-1 from the cells was inhibited. The release of TM antigen was not increased when total cellular TM level increased 1.3- or 1.4-fold relative to control cells after stimulation with 0.1-1.0 U/ml thrombin or 3 mM dibutyryl cAMP, respectively. Exposure of endothelial cells for 6 h to mixture of 1 μM N-formyl-methionyl-leucyl-phenylalanine (FMLP) and 100 ng/ml lipopolysaccharide (LPS) decreased cellular TM level by 30% relative to control cells without increase in the TM release. The FMLP and LPS-stimulated leukocyte treatment of the cells increased the release of TM antigens into the medium in a time-dependent manner and the increased release of TM antigen paralleled the extent of cell damage as measured by 51Cr release. Hydrogen peroxide treatment of the cells increased the release of TM antigens into the medium in a time- and concentration-dependent manner. The increased release of TM antigen by hydrogen peroxide also paralleled the extent of cell damage. Soluble TM antigen in conditioned medium from the untreated control cells was composed of six heterogeneous fragments of 105, 56, 48, 33, 31 and 28 kDa observed on Western blots after sodium dodecyl sulfatepolyacrylamide gel electrophoresis under reducing conditions, and the soluble TM antigen from the hydrogen peroxide-treat-ment cells was composed of five heterogeneous fragments of 80, 56, 33, 31 and 28 kDa. These compositions were quite similar to that observed for soluble TM fragments in human plasma. It is suggested that soluble TM antigen is not secreted from endothelial cells, but results from cellular damage.
Carcinoma del uraco: una extraña entidad
Authors: Gómez San Martín Maria , Gil Guerra Ana , Sanchez Lite Israel , Herreros Rodriguez José
Published: July 2018

Objetivo Revisar la patología tumoral del uraco, haciendo énfasis en su clínica, los métodos diagnósticos empleados y el manejo terapéutico.

Métodos Presentamos el caso de un varón de 39 años con carcinoma del uraco que simuló clínicamente un absceso umbilical.

Resultados Los hallazgos en la TC fueron sospechosos de patología del uraco. El examen anatomopatológico reveló células atípicas y la PET-TC demostró extensión a pared abdominal y epiplón, requiriéndose la resección completa.

Conclusiones El carcinoma del uraco es una neoplasia muy poco frecuente, que tiene su origen en el epitelio que recubre la luz del uraco, un vestigio de la alantoides que conecta la vejiga con el ombligo y normalmente involuciona en la etapa embrionaria. La clínica insidiosa hace que el diagnóstico sea tardío y el pronóstico pobre. Las pruebas de imagen tienen un papel fundamental en su sospecha, así como en la definición de la relación con la pared vesical y posible extensión local o a distancia. Una vez confirmado el diagnóstico histológicamente, está indicada la resección quirúrgica completa.
Prostatectomía radical y calidad de vida: resultados en un centro de alta complejidad
Authors: Sánchez Basto Catalina , Cataño Cataño Juan , Lizcano Herrera Ana , Chavarriaga Soto Julián , Orrego Rojas Paola , Monrroy Feijóo Eliana , Fakih García Nayib , Silva Herrera Jose
Published: July 2018

Introducción La prostatectomía radical (PR) es el patrón de oro para el manejo quirúrgico con intención curativa del cáncer de próstata. Sin embargo, tiene secuelas importantes como la incontinencia urinaria y la disfunción eréctil. El objetivo de este estudio es describir la prevalencia de las secuelas y el compromiso de calidad de vida de los pacientes llevados a PR abierta en un centro de alta complejidad.

Materiales y Métodos Se revisaron los datos de los pacientes llevados a prostatectomía radical en el Hospital Universitario San Ignacio desde el año 2005 hasta el año 2015. Se seleccionaron aquellos que tuvieran más de 12 meses de postoperatorio, previo consentimiento informado verbal por vía telefónica se aplicó el cuestionario UCLA PCI. La información fue organizada para su análisis en una base de datos construida con ese fin para posterior aplicación de las estadísticas descriptivas que permitieran resumir y describir los resultados.

Resultados Durante los años analizados, se realizaron 231 prostatectomías radicales. Se logró tener contacto con 112 de ellos a los cuales se les aplicó el cuestionario UCLA PCI. En el dominio de función urinaria, 57% de los pacientes reportan tener “control total de la orina,” 53% nunca tienen escape involuntario de la orina, 82% no requieren el uso de protectores y 62% presentan goteo de orina menos de 1 vez por semana. En cuanto a la función sexual, 69,3% califican su habilidad para tener una erección como pobre o muy pobre, 25% regular y 7% buena o muy buena. Para 20% la erección es suficiente para lograr el coito. Y para 52% esa función implica un problema en su vida. El impacto en la calidad de vida mostró que un 91,8% de los pacientes consideran que su salud es en general buena muy buena o excelente y un 70% no tienen ningún tipo de limitación física.

Conclusiones La prostatectomía radical tiene un impacto importante no despreciable en la calidad de vida de los pacientes, especialmente en lo referente a la función urinaria y sexual. Su impacto en la calidad de vida debe ser considerado al momento de realizar la consejería previa a la toma de decisiones en el manejo definitivo del cáncer de próstata con el fin de que el paciente tenga unas expectativas claras en ese sentido.
On the Fibrinolytic System in Aged Rats, and Its Reactivity to Endotoxin and Cytokines
Authors: Emeis J J , Brouwer A , Barelds R J , Horan M A , Durham S K , Kooistra T
Published: July 2018

Aged rats are more susceptible to endotoxin-induced effects, including microthrombosis and platelet aggregation, than are young rats. To investigate whether changes in the fibrinolytic system might be involved, we investigated the fibrinolytic activity in plasma euglobulin fractions and tissues (lung and heart) of young (6-months old) and aged (24-months old) rats under baseline conditions and after challenge with endotoxin. Aged rats had lower plasma levels of tissue-type plasminogen activator (t-PA) and of urokinase-type PA (u-PA) activity. PA inhibitor (PAI) activity was higher in the plasma of aged rats, as was t-PA activity in lung and heart.

Rats were treated with either a low dose (1 μg/kg) or a high dose (10 mg/kg) of endotoxin. Both treatments induced a transient phase of increased blood fibrinolytic activity, as evidenced by higher levels of tissue-type plasminogen activator (t-PA) activity and decreased levels of PA inhibitor (PAI) activity. Over time, the fibrinolytic activity decreased, probably due to increased levels of PA inhibitor.

Both the early increase in t-PA activity, and the subsequent increase in PAI activity, were more pronounced in the aged rats, as compared with the younger rats, after the high dose of endotoxin. The aged rats also responded to an injection of interleukin-1β or tumor necrosis factor-α with a larger increase of PAI activity than did the younger rats.

Together the data suggest that, compared to young rats, aged rats have a decreased base-line plasma fibrinolytic activity, while their fibrinolytic system is more responsive to challenge by endotoxin and cytokines.
Characterization of Partial Gene Deletions in Type III von Willebrand Disease with Alloantibody Inhibitors
Authors: Mancuso David J , Tuley Elodee A , Castillo Ricardo , de Bosch Norma , Mannucci Pler M , Evan Sadler J
Published: July 2018

von Willebrand factor gene deletions were characterized in four patients with severe type III von Willebrand disease and alloantibodies to von Willebrand factor. A PCR-based strategy was used to characterize the boundaries of the deletions. Identical 30 kb von Willebrand factor gene deletions which include exons 33 through 38 were identified in two siblings of one family by this method. A small 5 base pair insertion (CCTGG) was sequenced at the deletion breakpoint. PCR analysis was used to detect the deletion in three generations of the family, including two family members who are heterozygous for the deletion. In a second family, two type III vWD patients, who are distant cousins, share an -56 kb deletion of exons 22 through 43. The identification and characterization of large vWF gene deletions in these type III vWD patients provides further support for the association between large deletions in both von Willebrand factor alleles and the development of inhibitory alloantibodies.
Comparison of Once-Daily Subcutaneous Fragmin® with Continuous Intravenous Unfractionated Heparin in the Treatment of Deep Vein Thrombosis
Authors: Lindmarker Per , Holmström Margareta , Granqvist Staffan , Johnsson Hans , Lockner Dieter
Published: July 2018

Two hundred and four consecutive patients with venographically confirmed deep vein thrombosis (DVT) were randomised either to a low molecular weight heparin, Fragmin®, administered subcutaneously (s.c.) once daily as a fixed dose of 200IU anti-factor Xa/kg or to continuous intravenous infusion of unfractionated heparin (UFH). The UFH dose was adjusted to maintain the activated partial thromboplastin time between 1.5 and 3.0 times the upper limit of the reference value at each centre. Fragmin® or UFH was given for a minimum of 5 days until anticoagulation with warfarin, given from day 1, was established (i. e. an International Normalised Ratio, of 2.0−3.0). A second venogram was obtained after Fragmin® or UFH treatment. There were no significant differences in the change in mean Marder score before and after treatment between the two treatment groups, irrespective of thrombus localisation. No major bleeding events, symptomatic pulmonary embolism, symptomatic thrombosis progression or death occurred during hospitalisation. Eight documented venous thromboembolic events occurred before the follow-up visit 6 months after randomisation: 5 in patients treated with Fragmin® and 3 in those treated with UFH. Six of these events occurred after cessation of warfarin treatment. In conclusion Fragmin® given s.c. once daily in a fixed dose adjusted for body weight, is no less effective or safe than a continuous infusion of UFH in the initial treatment of acute DVT.
Prevalence, Follow-Up and Clinical Significance of the Anticardiolipin Antibodies in Normal Subjects
Authors: Vila P , Hernández M C , López-Fernández M F , Batlle J
Published: July 2018

To date very few studies that analyze the prevalence of anticardiolipin antibodies (ACA) in healthy subjects have been reported. No data based on a systematic analysis of normal subjects with positive ACA is available. The aim of the present study was to evaluate the prevalance of ACA, its clinical significance and relationship to the lupus anticoagulant (LA) and other autoimmune parameters in an apparently healthy population. 552 normal blood donors from a blood bank were randomly selected. ACA positive donors who consented were monitored over a period of twelve months and tested every three months. ACA (IgG and IgM isotypes) were quantitated by enzyme linked immunoassay (ELISA). The prevalance for IgG ACA in our donor population was estimated to be 6.5%, and 9.4% for IgM ACA, which is similar to the one previously reported for IgG and slightly higher for IgM. It is worth noting that in our study ACA positive donors exhibited a progressive negativization. Eight donors with IgG ACA and seven with IgM ACA remained positive for nine months. Five donors with IgG ACA and four with IgM ACA had family history of thromboembolic disease. One donor with IgG ACA and two with IgM ACA had had unexplained miscarriages in the past. We did not find any relationship between ACA and LA, nor between ACA positivity and the clinical and laboratory data studied. Pseudopositivity for lues was not found. No thrombotic event occurred in donors that were positive for ACA during the 12-month follow-up.
Characterisation of Persistent Anti-Xa Activity Following Administration of the Low Molecular Weight Heparin Enoxaparin Sodium (Clexane)
Authors: Brieger David , Dawes Joan
Published: July 2018

It is widely reported that persistent anti-Xa activity follows administration of low molecular weight heparins. To identify the effectors of this activity we have injected 125I-labelled Enoxaparin sodium into rabbits and subsequently analysed the circulating radiolabelled material and anti-Xa activity by affinity and size exclusion chromatography. Antithrombin III-binding material derived from the injected drug was responsible for all the anti-Xa amidolytic activity. At early times after injection additional anticoagulant activity which was largely attributable to tissue factor pathway inhibitor was measured by the Heptest clotting assay after removal of glycosaminoglycans from plasma samples. Small radiolabelled fragments, including penta/hexasaccharide with affinity for antithrombin III, were detectable in the circulation 1 week later, and sulphated oligosaccharides persisted for 3-4 weeks. Significant quantities of radiolabel remained in the liver and kidney several weeks post-injection; these organs may sequester some of the injected drug and give rise to circulating biologically active material by degradation and secretion of catabolic products into the plasma.