Recurrent antiphospholipid-related deep vein thrombosis as presenting manifestation of systemic lupus erythematosus

Antiphospholipid antibodies (aPL) are frequently associated with thrombotic disorders in the so-called antiphospholipid syndrome. Together with anticardiolipin antibodies (aCL), lupus anticoagulant (LA) is the main diagnostic tool for aPL detection. Since LA determination is based on the finding of prolonged clotting time in vitro, concomitant anticoagulant therapy may significantly interfere with its detection. We report a case of a boy in whom recurrent aPL-related thrombosis heralded for several months the onset of systemic lupus erythematosus (SLE). Abnormally increased in vitro clotting times at the time of the second thrombotic event led to the suspicion of the presence of LA activity. However, this latter finding was difficult to interpret since the patient was already on heparin treatment at the time of our first observation. Thus, LA was assayed using a commercial kit in which a heparin neutralizer is included (Staclot LA). Two consecutive samples from the patient were compared with eight patients on anticoagulant therapy for non-aPL-related thrombotic events and 20 healthy controls. The study showed that, taking into account the concomitant anticoagulant treatment, Staclot LA was positive only in the propositus, raising the suspicion of a possible aPL-related origin of the thrombotic event. This issue was definitively confirmed in a subsequent follow-up. Conclusion The present report shows that aPL-related deep vein thrombosis can be the earliest clinical manifestation of pediatric SLE, and that Staclot LA may have a role in LA detection during the course of anticoagulant treatment. Received: 6 October 1998 / Accepted: 15 September 1999     

Long-term outcome of patients with monostotic Ewing's sarcoma treated with combined modality

One hundred and twenty-one consecutive patients with monostotic Ewing's sarcoma (ES) were treated according to three consecutive combined modality programs from 1974 to 1986. Their 3-year progression free survival (PFS) rate from diagnosis of 59% was identical to the event free survival (EFS) rate, since all the 50 events occurring within 3 years from diagnosis were tumor recurrences. Primary tumor was treated with radiotherapy in 75 cases, surgical resection plus radiotherapy in 38, and radical surgery in 8. Chemotherapy was given to all patients and each program included adriamycin, vincristine, and cyclophosphamide ± dactinomycin. Median follow-up was 12 years, ranging from 6 to 19 years. The PFS rate decreased to 49% at 6 years and plateaued at 46% after the 7th year from diagnosis, even though some relapses were observed as late as 14 years from diagnosis. Second malignancies developed in 7 patients free from progressive ES and were represented by osteogenic sarcoma in previously irradiated bone in 4 cases and by breast carcinoma in 3. No other event but tumor relapse or second malignancy occurred in this series. EFS rate was 47% at 6 years and 39% at 12 years, further decreasing in the following years because of a number of late events. A continuous PFS longer than 7 years may be consistent with cure in the majority of patients with monostotic ES. However, these patients should be followed indefinitely because of risk of second malignancies. © 1994 Wiley-Liss, Inc.     

Histamine release by free radicals: Paracetamol-induced histamine release from rat peritoneal mast cells afterin vitro activation by monooxygenase

The incubation of paracetamol with isolated rat serosal mast cells evokes the release of histamine only in the presence of (S10) liver microsomes obtained from PCB or phenobarbital treated rats. The release of histamine was not accompanied by a leakage of lactate dehydrogenase and was blocked by the antioxidant -tocopherol and by D-mannitol, an hydroxyl free radicals scavenger. The data are consistent with the metabolic oxidation of paracetamol in the generation of reactive intermediates capable of activating the sequential exocytosis.     

Survival of adults treated for medulloblastoma using paediatric protocols

We retrospectively studied 26 consecutive adults treated for medulloblastoma using paediatric protocols. Between 1987 and 2003, patients 18 years old were given adjuvant chemotherapy consisting of one of two 'paediatric' regimens (depending on the time of presentation) and craniospinal local-boost radiotherapy: regimen A (n = 12), vincristine (VCR), intrathecal and/or intravenous methotrexate and conventional radiotherapy; or regimen B (n = 11) sequencing intensive doses of multiple agents followed by hyperfractionated accelerated radiotherapy (HART). A VCR-lomustine-based maintenance followed both regimens. Three additional patients received a tailored treatment due to their impaired neurological status after surgery. The median age at diagnosis was 26 years (range 18-41 years). With a median follow-up of 46 months, 5-year disease-free and overall survival rates were 65+/-11% and 73+/-10%, respectively, for the series as a whole. All patients who received regimen B (5 of whom had metastatic Chang M2-M3 disease) are alive with no evidence of disease at 39 months. Although the number of patients is limited, our data suggest that the sandwich sequential, moderately intensive chemotherapy in combination with HART is an effective treatment for medulloblastoma in adults, and this approach seems to overcome previously-recognised risk factors.     

Different cellular responses evoked by natural and stoichiometric synthetic chrysotile asbestos

The carcinogenic potency of asbestos, including chrysotile, is well established. Several physico-chemical features of the fibers appear implied, such as fibrous habit, size, crystallinity, morphology, and surface active metal ions, where free radical generation may take place. In contrast to other asbestos forms, iron is not a stoichiometric component of chrysotile, but is only present together with other extraneous ions as a magnesium- and silicon-replacing contaminant. To determine the role played by contaminating ions and morphological features of the fibers, a stoichiometric chrysotile with constant structure and morphology was synthesized in hydrothermal conditions. Free radical generation and the effects of these fibers on human lung epithelial A549 cells have been compared to that elicited by a well known toxic natural chrysotile (UICC A, from Rhodesia). After a 24-h incubation, the natural, but not the synthetic, form exerted a cytotoxic effect, detected as leakage of lactate dehydrogenase. Homolytic rupture of a C-H bond and lipoperoxidation in A549 cells took place in the presence of the natural, but not of the synthetic, chrysotile. Antioxidant systems were also affected differently. The pentose phosphate pathway and its regulatory enzyme glucose 6-phosphate dehydrogenase were markedly inhibited only by the natural specimen, which also caused a depletion of intracellular reduced glutathione in A549 cells. These results suggest that metal ions, fiber size and state of the surface play a crucial role in the oxidative stress caused by chrysotile asbestos. Stoichiometric synthetic fibers may thus be proposed as a reference standard (negative control) for toxicological studies.     

Direct measurement of ankle stiffness during quiet standing: implications for control modelling and clinical application

In this study, we describe a device for the direct measurement of intrinsic ankle stiffness in quiet standing. It consists of a motorised footplate mounted on a force platform. By generating random sequences of step-like disturbances (1° amplitude, 150 ms duration) and measuring the corresponding displacements of the center of pressure in the antero-posterior direction, we obtained torque-rotation patterns after aligning, averaging, and scaling the postural responses. Such patterns were used for estimating the value of the ankle stiffness, which was normalized as a fraction of the critical value. In order to be confident that the measurements addressed the intrinsic ankle stiffness and were not affected in a significant way by the reflex activation of the muscles in response to the test disturbances, we performed the estimates in different ways: least squares estimates with time windows of different widths and an instantaneous estimate at the time in which the angular acceleration vanishes. The statistical analysis showed that there is no significant difference among the different methods of estimate and the inspection of the electromyographic activity in response to the perturbations showed that at least two of the estimates were certainly outside the possible influence of reflex patterns. The intrinsic ankle stiffness was evaluated to be 64 ± 8% of the critical stiffness for test disturbances of the order of 1°. We argue that this figure identifies the lower bound of the range of values which characterise normal sway in quiet standing, whereas the upper bound is given by the estimates performed with much smaller test disturbances [1] which yield a higher value: 91 ± 23%. The two estimation paradigms (with very small and very large test disturbances, respectively) are complementary also because they behave in a different way as regards the sensitivity to a bias torque: it is close to zero in the Loram & Lakie’s paradigm, whereas it is significant in our paradigm. Thus, as the bias grows, it appears that the range of stiffness values is narrowed and is pushed towards the upper bound. There is a clear potential for the clinical application of these methods, in the sense that the identification of the range of stiffness values used by a patient is a measurable index of motor organisation/reorganisation.     

Herpes Simplex Virus Amplicon Delivery of a Hypoxia-Inducible Soluble Vascular Endothelial Growth Factor Receptor (sFlk-1) Inhibits Angiogenesis and Tumor Growth in Pancreatic Adenocarcinoma

Background Tumor hypoxia induces vascular endothelial growth factor (VEGF) expression, which stimulates angiogenesis and tumor proliferation. The VEGF signaling pathway is inhibited by soluble VEGF receptors (soluble fetal liver kinase 1; sFlk-1), which bind VEGF and block its interaction with endothelial cells. Herpes simplex virus (HSV) amplicons are replication-incompetent viruses used for gene delivery. We attempted to attenuate angiogenesis and inhibit pancreatic tumor growth through HSV amplicon–mediated expression of sFlk-1 under hypoxic control. Methods A multimerized hypoxia-responsive enhancer (10 × HRE) was cloned upstream of the sFlk-1 gene (10 × HRE/sFlk-1). A novel HSV amplicon expressing 10 × HRE/sFlk-1 was genetically engineered (HSV10 × HRE/sFlk-1).Human pancreatic adenocarcinoma cells (AsPC1) were transduced with HSV10 × HRE/sFlk-1 and incubated in normoxia (21% oxygen) or hypoxia (1% oxygen). Capillary inhibition was evaluated by human umbilical vein endothelial cell assay. Western blot assessed sFlk-1 expression. AsPC1 flank tumor xenografts (n = 24) were transduced with HSV10 × HRE/sFlk-1. Results Media from normoxic AsPC1 transduced with HSV10 × HRE/sFlk-1 yielded a 36% reduction in capillary formation versus controls (P < .05), whereas hypoxic AsPC1 yielded a 76% reduction (P < .005). Western blot of AsPC1 transduced with HSV10 × HRE/sFlk-1 demonstrated greater sFlk-1 expression in hypoxia versus normoxia. AsPC1 flank tumors treated with HSV10 × HRE/sFlk-1 exhibited a 59% reduction in volume versus controls (P < .000001). Conclusions HSV amplicon delivery of a hypoxia-inducible soluble VEGF receptor significantly reduces new vessel formation and tumor growth. Tumor hypoxia can thus be used to direct antiangiogenic therapy to pancreatic adenocarcinoma.