The rapid assembly of an elliptical galaxy of 400 billion solar masses at a redshift of 2.3.

Stellar archaeology shows that massive elliptical galaxies formed rapidly about ten billion years ago with star-formation rates of above several hundred solar masses per year. Their progenitors are probably the submillimetre bright galaxies at redshifts z greater than 2. Although the mean molecular gas mass (5 × 10(10) solar masses) of the submillimetre bright galaxies can explain the formation of typical elliptical galaxies, it is inadequate to form elliptical galaxies that already have stellar masses above 2 × 10(11) solar masses at z ≈ 2. Here we report multi-wavelength high-resolution observations of a rare merger of two massive submillimetre bright galaxies at z = 2.3. The system is seen to be forming stars at a rate of 2,000 solar masses per year. The star-formation efficiency is an order of magnitude greater than that of normal galaxies, so the gas reservoir will be exhausted and star formation will be quenched in only around 200 million years. At a projected separation of 19 kiloparsecs, the two massive starbursts are about to merge and form a passive elliptical galaxy with a stellar mass of about 4 × 10(11) solar masses. We conclude that gas-rich major galaxy mergers with intense star formation can form the most massive elliptical galaxies by z ≈ 1.5.

On the redshift distribution and physical properties of ACT-selected DSFGs.

We present multi-wavelength detections of nine candidate gravitationally-lensed dusty star-forming galaxies (DSFGs) selected at 218GHz (1.4mm) from the ACT equatorial survey. Among the brightest ACT sources, these represent the subset of the total ACT sample lying in Herschel SPIRE fields, and all nine of the 218GHz detections were found to have bright Herschel counterparts. By fitting their spectral energy distributions (SEDs) with a modified blackbody model with power-law temperature distribution, we find the sample has a median redshift of z = 4.1 - 1.0 + 1.1 (68 per cent confidence interval), as expected for 218GHz selection, and an apparent total infrared luminosity of log 10 ( µ L IR / L ⊙ ) = 13.86 - 0.30 + 0.33 , which suggests that they are either strongly lensed sources or unresolved collections of unlensed DSFGs. The effective apparent diameter of the sample is µ d = 4.2 - 1.0 + 1.7 kpc , further evidence of strong lensing or multiplicity, since the typical diameter of dusty star-forming galaxies is 1.0-2.5 kpc. We emphasize that the effective apparent diameter derives from SED modelling without the assumption of optically thin dust (as opposed to image morphology). We find that the sources have substantial optical depth. ( τ = 4.2 - 1.9 + 3.7 ) to dust around the peak in the modified blackbody spectrum (λ obs ⩽ 500µm), a result that is robust to model choice.

Urokinase-type plasminogen activator release after DDAVP in von Willebrand disease: different behaviour of plasminogen activators according to the synthesis of von Willebrand factor.

Nine healthy volunteers and 23 patients with various types of von Willebrand disease were studied before and after DDAVP infusion. We investigated the behaviour of factor VIII/von Willebrand factor measurements, and of tissue plasminogen activator and urokinase-type plasminogen activator. In mild von Willebrand disease the increase of both plasminogen activators was similar to that seen in normal controls. A different fibrinolytic behaviour was found in the type I platelet low and in the type III von Willebrand disease patients. An impaired and absent fibrinolytic response to DDAVP was seen in the former and in the latter von Willebrand disease, respectively. A close relation between either u-PA and t-PA or von Willebrand factor was observed. The possibility of a linkage among these three proteins was discussed.

Venous thrombosis and tissue plasminogen activator release deficiency: a family study.

Thrombotic events are often due to fibrinolytic defects such as impaired tissue plasminogen activator (tPA) synthesis and/or release or increased plasminogen activator inhibitor (PAI) levels. In this report we describe four members of a family with a history of recurrent venous thrombosis, who demonstrated defective tPA release after dynamic tests. Two symptomatic patients and one asymptomatic individual showed absent or abnormally low tPA antigen (tPA:Ag) and activity (PA) increases after DDAVP infusion and/or 20 min of venous occlusion. In these patients PAI values were slightly higher than controls. A satisfactory tPA:Ag release was found in the fourth asymptomatic patient. All other coagulation tests were within the normal ranges. This familial defect of the fibrinolytic system seems to be inherited as an autosomal trait.

The fibrinolytic potential in patients with Cushing's disease: a clue to their hypercoagulable state.

The aim of our study was to determine the fibrinolytic potential in a large group of patients with Cushing's disease. These patients had a significant shortening of the activated partial thromboplastin time and increase in factor VIII/von Willebrand factor complex compared to normal controls. The mean levels of plasminogen, tissue plasminogen activator (t-PA) antigen and plasminogen activator inhibitor (PAI) activity were significantly higher than in normal subjects, whereas the basal fibrinolytic activity was similar to that seen in the control group. In 17 out of 30 Cushing patients and in 17 normal subjects the fibrinolytic potential was determined with the venous occlusion test. In the Cushing group, the release of t-PA antigen after 20 min of venous occlusion was comparable to that observed in the control group. However, Cushing patients showed a lower fibrinolytic activity than normal subjects, since a lesser shortening of the euglobulin lysis time and a non-significant rise of plasminogen activator activity levels were found. Moreover, in these patients the PAI activity values remained unchanged and significantly increased after venous occlusion test also. In conclusion, the impaired fibrinolytic activation seen in Cushing patients after venous occlusion can be explained by the inhibitory effect of the high PAI levels on plasminogen activators. The defective fibrinolytic potential could further contribute to the hypercoagulable state in Cushing's disease. High PAI levels before surgery may represent an additional risk factor for post-surgical thromboembolic complications in Cushing patients.

Protein C, factor VII and prothrombin time as early markers of liver function recovery or failure after liver transplantation.

Irreversible initial non-function of the graft liver is a life-threatening early complication of orthotopic liver transplantation (OLT), which needs immediate retransplantation if the patient is to survive. Since protein C (PC) is a vitamin K dependent protein synthesized in the liver and with the same half-life as factor VII (FVII), the behaviour of PC in patients undergoing OLT was studied in comparison with prothrombin time (PT) and FVII. Twelve OLT patients were divided into two groups on the basis of clinical outcome: group A (six cases) in which OLT was successful, and group B (six cases) who developed initial non-function of the graft liver. PT, FVII activity (FVII:act) and antigen (FVII:Ag) and PC activity (PC:act) and antigen (PC:Ag) were carried out on six blood samples collected during the operation. At baseline, coagulation disorders were in agreement with the underlying liver disease, but no differences were seen between the two groups when all tests were considered. Ten minutes, 1, 2 and 3 h after liver reperfusion, mean PT and FVII:act were always significantly increased in good responder patients compared to non-responders. FVII:Ag and PC:Ag were significantly higher in group A than in group B starting 2 h after the liver graft reperfusion; no difference was seen in PC:act levels between the two groups. In addition, PC:Ag mean levels were increased with respect to corresponding PC:act values in non-responder patients, suggesting a qualitative rather than quantitative defect of protein synthesis due to liver damage. In conclusion, PT and FVII:act were more sensitive than PC activity as early prognostic indices of clinical outcome in OLT.

Mild haemophilia A fails to protect from coronary artery disease: the report of two cases.

The description of two additional cases of coronary artery disease in haemophiliacs is reported. Both patients are affected by mild haemophilia A. The first one was not aware of his coagulation disorder and therefore he had never been treated with FVIII concentrates, despite the occurrence of severe and recurrent articular and gastric bleeding episodes. He underwent cardiac catheterization that gave evidence of extensive coronary atherosclerosis. Percutaneous transluminal coronary angioplasty (PTCA) was then performed. The second patient had an inferior myocardial infarction. Influence of cardiovascular risk factors in haemophiliacs and the possible role of thrombosis in the pathogenesis of atherosclerosis are discussed.

Unsuitability of laser nephelometer in the evaluation of factor VIII antigen.

We developed assays for the measurement of Factor VIII in a Laser Nephelometer and the results were compared with those obtained by conventional immunological methods. Marked discrepancies were obtained using different antisera and only the Dako antiserum lot 42 B yielded satisfactory results. Other antisera used (other lots of Dako antiserum, Behringwerke antiserum and Immunoscientific antiserum) failed to yield satisfactory results. From our data it seems that Laser Nephelometer has no role in the evaluation of Factor VIII complex. Statements to the contrary have to be accepted with great caution.

Fibrinolytic behavior in long-standing branch retinal vein occlusion.

The aim of our study was to evaluate the fibrinolytic system in patients with retinal branch vein occlusion (RVO). The following tests were carried out: prothrombin time, partial thromboplastin time (PTT), fibrinogen degradation products, euglobulin lysis time, fibrinogen, pasminogen, antithrombin III, alpha 2-antiplasmin and alpha 2-macroglobulin. Comparing the results of patients with those of normal controls, only the fibrinogen increase and PTT shortening were significantly different. All other tests taken into account were within normal limits. Only the patients without other associated diseases (diabetes or hypertension) showed a significant activation of fibrinolysis (either with respect to normal or to other RVO patient groups). In conclusion, no important fibrinolytic impairment was seen in our longstanding RVO patients. Fibrinolytic activation seen in patients without verified associated diseases may be related to the presence of a sound endothelium, still able to release plasminogen activators in response to RVO. The fibrinogen and PTT changes in RVO were probably due to other associated diseases.

Unusual thrombotic-like retinopathy (Coats' disease) associated with congenital plasminogen deficiency type I.

A new kindred with heterozygous plasminogen deficiency type I is described. The proband, a 17-year-old male, showed a peculiar thrombotic-like retinal picture compatible with Coats' disease. Extensive coagulation studies revealed decreased levels of both plasminogen activity and antigen to about 50% of normal values. Five out of 13 family members from the paternal side showed the same fibrinolytic defect. In two cases, a history of recurrent phlebites of the lower limbs was present. One unaffected patient also had a superficial phlebites at a young age; her plasminogen levels were shown to be within normal limits, but a long-standing oestroprogestinic intake could have influenced and normalized the results. No other family member showed retinal abnormality. This is the first case of hypoplasminogenaemia associated with Coats' disease. A possible role of the fibrinolytic defect in the pathogenesis of this unusual retinopathy is suggested. Finally, the occurrence of thrombotic manifestations in other affected family members supports the opinion that plasminogen deficiency should be considered as a potential risk factor for thrombosis.

Laser nephelometer evaluation of factor IX.

Laser Nephelometry is a technique which allows the evaluation of the concentration of several serum proteins and clotting factors. By means of this technique it is also possible to study the kinetic of the reaction between antigen and antibody. In a few instances the method was also applied in the characterization of abnormal molecules. We developed assays for the measurement of Factor IX antigen and the results were compared with those obtained by conventional immunological methods such as rocket immunoelectrophoresis. Plasmas from patients with haemophilia B, on coumarin treatment, with liver cirrhosis were studied. A standard reference curve was obtained using pooled normal plasma. The factor IX levels obtained by laser nephelometer correlated fairly well with those obtained by electroimmunoassay.

Anti-hepatitis C virus serology in patients affected with congenital coagulation defects: a comparative study using three second generation ELISA tests.

We determined the prevalence of anti-hepatitis C virus (HCV) antibodies in 34 patients affected with congenital coagulation disorders attending the Haemophilia Centre of Padua, Italy. Serological tests were carried out by three second generation enzyme linked immunosorbent assays (ELISA), two based on recombinant proteins (Ortho and Abbott) and one based on synthetic peptides (Behring) as antigenic substrate. The repeatedly reactive specimens were further assayed by the supplemental 4-antigen recombinant immunoblot assay (RIBA) (Chiron and Ortho). Moreover, we performed the dot-blot Matrix test (Abbott) on the samples showing discrepant results by the three ELISA tests. Twenty-six patients (76.5%) were anti-HCV positive using all three ELISA tests; 25 were confirmed by the supplemental RIBA test, the other one was indeterminate. Two samples were in a gray-zone only using the anti-HCV ELISA Abbott. These were positive by the RIBA; in contrast, such samples showed no reactivity with the Matrix test. In accordance with the current literature, these data show an equivalence between the 2nd generation screening tests (ELISA), at least when applied to a high risk population as in the present study. Further, these screening tests demonstrated a reliable specificity, since most of the ELISA-reactive specimens were confirmed by the supplemental RIBA test. In contrast, combined use of the anti-HCV tests could be useful when high sensitivity is requested, as in the case of blood donor pretransfusion screening.

Fibrinolysis and coagulation abnormalities in systemic lupus erythematosus. Relationship with Raynaud's phenomenon, disease activity, inflammatory indices, anticardiolipin antibodies and corticosteroid therapy.

Endothelial cell damage in systemic lupus erythematosus (SLE) was evaluated by measuring fibrinolytic activity and von Willebrand factor levels. Tissue-type plasminogen activator (t-PA) antigen, plasminogen activator inhibitor (PAI) activity, and von Willebrand factor antigen (vWF:Ag) and activity (vWF:RCof) were measured in 21 SLE patients (12 of whom were therapy free) and 22 controls. In addition, the relationship between such parameters and Raynaud's phenomenon, disease activity [according to personal criteria, Systemic Lupus Activity Measure (SLAM) and European Consensus Lupus Activity Measurement (ECLAM) scores] inflammatory indices [ESR, C-reactive protein (CRP), alpha 2-globulin], anticardiolipin antibodies and corticosteroid therapy was investigated. Lower levels of t-PA antigen (P = 0.003) and higher levels of vWF:Ag (P = 0.001) were found in SLE patients in comparison with controls. Moreover, t-PA antigen was lower (P = 0.02) in steroid-free patients in comparison with those taking steroids. No relationship was found between fibrinolysis and coagulation abnormalities and Raynaud's phenomenon, disease activity, inflammatory indices and anticardiolipin antibodies. Endothelial cell damage is probably a common feature in SLE patients; nevertheless, we were unable to clarify the nature of such abnormality. It is worth noting that low doses of steroids seem to be effective in improving endothelial cell function in SLE patients.

Fibrinolytic effects of defibrotide in atherosclerotic patients.

Defibrotide is a polydeoxyribonucleotide salt that shows antithrombotic activity through a suggested profibrinolytic mechanism. To study the effectiveness of defibrotide in atherosclerosis, we evaluated the fibrinolytic and coagulation behavior in normal subjects and patients with atherosclerotic disease, before and after single or repeated intravenous defibrotide infusion. A significant shortening of the ELT was found in all subjects. However, since neither t-PA increase nor PAI decrease was observed, we suggest that the profibrinolytic response to defibrotide may be due to mechanisms other than t-PA stimulation. Our results provide further evidence for the usefulness of defibrotide antithrombotic prophylaxis in atherosclerosis.

Fibrinolytic effect of a particular glycosaminoglycan (endoglycan) per os on normals and in patients with chronic artery disease.

Endoglycan, a heparan-dermatan sulphate association, is a highly purified heparinoid extracted from porcine intestinal mucosa. The aim of our study was to investigate the fibrinolytic system in a group of healthy controls and vascular disease patients, before and after endoglycan administration "per os". All the patients had a reduced basal fibrinolytic activity. The tests carried out were PT, PTT, FDP, Euglobulin Lysis Time (ELT), fibrinogen, plasminogen, alpha 2-antiplasmin, alpha 2-macroglobulin and t-PA activity assayed with a chromogenic method. After endoglycan administration, we have shown a significant shortening of ELT with complete normalization during the treatment. A fibrinogen decrease and either plasminogen or alpha 2-antiplasmin increase was seen. This was shown in normals too, however to a lesser extent. During therapy most of the healthy subjects, but only some patients, showed increased t-PA levels. Before and during treatment, significantly higher t-PA levels were seen in the control group as compared to the patients group. Reduced t-PA release was seen in our vascular disease patients. In conclusion, endoglycan "per os" appears to exert a stimulatory effect on the fibrinolytic system.

Fibrinolytic pattern in recurrent spontaneous abortions: no relationship between hypofibrinolysis and anti-phospholipid antibodies.

Patients with antiphospholipid antibodies may suffer from thrombotic events and recurrent spontaneous abortions. A defective fibrinolytic potential has been described in women with recurrent fetal losses. We investigated the prevalence of anticardiolipin antibodies and of various fibrinolytic abnormalities in 64 females with a history of at least two abortions of unknown origin. Anticardiolipin antibodies were present in the serum of 31 patients (48.4%). The overall prevalence of fibrinolytic disorders was 67.2% (43 cases) and resulted significantly higher than that of aCL positivity (P = 0.03). In most of cases the impaired fibrinolytic potential after venous occlusion test was due to increased PAI-1 levels; only in a few instances a defective fibrinolytic response was due to reduced t-PA release, a combined defect or an intrinsic fibrinolytic deficiency. After division of patients in two groups on the basis of the aCL presence, the distribution of different fibrinolytic defects was similar in aCL positive and negative women, suggesting the lack of correlation between hypofibrinolysis and aCL antibodies. Plasminogen abnormalities resulted compatible with congenital hypoplasminogenemia in two aCL negative women, whereas in four aCL positive patients they were suggestive for acquired dysplasminogenemia. Our results indicate that patients with recurrent spontaneous abortions may present fibrinolytic disorders, which occur independently and more often than aCL positivity. An accurate investigation of the fibrinolytic potential, and, namely, of PAI-1 levels, should be included in the study of females suffering from repeated fetal losses.

Aprotinin efficacy on intraoperative bleeding and transfusion requirements in orthotopic liver transplantation.

BACKGROUND: Bleeding complications frequently occur during orthotopic liver transplantation (OLT), particularly in patients with liver cirrhosis. Enhanced fibrinolytic activity in plasma was seen to play a key role in the development of the hemostatic disorder and of hemorrhages. Aprotinin, a serine protease inhibitor, has been used in the prevention and/or treatment of hyperfibrinolytic states. STUDY DESIGN AND METHODS: In the present study, the effect of aprotinin on bleeding complications and transfusion requirements was investigated in OLT patients with liver cirrhosis. Seven consecutive cirrhotic patients undergoing OLT were infused with aprotinin following an original protocol (1,000,000-KIU intravenous loading dose plus 500,000 kallikrein-inhibitory units per hour until skin closure). Seven previous cirrhotic OLT patients not receiving aprotinin were used as controls. RESULTS: In the treated group, a significant decrease in the number of transfused units of packed red cells (48.7%, p < 0.01), fresh-frozen plasma (24.4%, p < 0.05), platelets (35.9%, p < 0.01), and autologous blood (55.2%, p < 0.01) was observed as compared with the control group. Moreover, the mean length of operation was significantly shorter in the aprotinin-infused patients than in untreated patients (8.3 +/- 1.2 vs. 10.1 +/- 1.8 hours, respectively; p < 0.01)). In the aprotinin-treated group, the antifibrinolytic efficacy was confirmed by the lack of increase in D-dimer levels and decrease of fibrinogen in plasma; on the contrary, these changes were always seen in the group not receiving aprotinin. CONCLUSION: Infusion of aprotinin during OLT in cirrhotic patients can be recommended for the prevention of hyperfibrinolysis-triggered bleeding, thus reducing transfusion requirements. A possible protective effect on the primary nonfunction of the grafted liver is suggested.