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Biomedical subjects

F Velasco

Publications and source records attributed to F Velasco.

At least 19 recordsLinked to original sources
PubMed2000

Seizures induced by penicillin microinjections in the mesencephalic tegmentum.

The location and extension of a convulsive area in the brain stem in cats was determined through penicillin microinjections (0.5-1.0 microl) of a concentrated sodium penicillin solution (500 IU/microl), stereotactically oriented to multiple structures, in fully awake animals, partially restrained through a rod fixation system that avoided pain, allowed the observation of clinical seizures and simultaneous recording of EEG, EMG and multiple unit activity (MUA) from the injected site and the motor cortex (Cx). Clinical and EEG seizure patterns in relation to the injected sites and penicillin doses were studied in another group of animals using doses from 12.5 IU/0.1 microl to 125 IU/1.0 microl. The time relationship between muscular clonus, EEG spikes and MUA at the injected site and Cx were analyzed. The only area in which penicillin induced seizures was the mesencephalic tegmentum (MT). The amount of penicillin but not the stereotactic coordinates determined the seizure type. MT EEG and MUA paroxysms anticipated clinical seizure and Cx EEG spikes. When Cx EEG appeared, they were accompanied by an increase in MUA beginning in the Cx and EMG, followed by significant increase in MT MUA. The sequence of events suggest that MT seizure activity propagates via alternative pathways not involving direct reticulospinal or pyramidal tract pathways.

Animals↗
PubMed2000

Subacute electrical stimulation of the hippocampus blocks intractable temporal lobe seizures and paroxysmal EEG activities.

PURPOSE: To investigate the clinical, electroencephalographic (EEG), and histopathologic effects of subacute electrical stimulation of the hippocampal formation or gyrus (SAHCS) on 10 patients with intractable temporal lobe seizures. METHODS: Bilateral, depth, hippocampal or unilateral, subdural, basotemporal electrodes were implanted in all 10 patients for a topographic diagnosis of the site and extent of the epileptic focus before a temporal lobectomy. In all patients, antiepileptic drugs (AEDs) were discontinued from 48 to 72 h before a program of continuous SAHCS, which was performed for 2-3 weeks. Stimulation parameters were biphasic Lilly wave pulses, 130/s in frequency, 450 micros in duration, and 200-400 microA in amplitude. The stimuli were delivered 23 of every 24 h for the 2-3-week SAHCS period. The effects of SAHCS on the number of clinical seizures per day and the percentage of interictal EEG spikes per 10-second samples of maximal paroxysmal activity at the epileptic focus were determined daily during the 16 days of SAHCS. At the completion of this program, patients underwent an en bloc temporal lobectomy, and the histopathologic effects of SAHCS on the stimulated tissue were analyzed by means of light-microscopy studies. RESULTS: In seven patients whose stimulation electrode contacts were placed within the hippocampal formation or gyrus and who experienced no interruption in the stimulation program, SAHCS abolished clinical seizures and significantly decreased the number of interictal EEG spikes at the focus after 5-6 days. The most evident and fast responses were found by stimulating either the anterior pes hippocampus close to the amygdala or the anterior parahippocampal gyrus close to the entorhinal cortex. Other surface, hippocampal, and basotemporal EEG signs predicted and accompanied this antiepileptic response. These included an electropositive DC shift and monomorphic delta activity at the medial hippocampal and parahippocampal regions, and a normalization of the background EEG activity and signs of slow-wave sleep in surface. depth, and subdural regions. In contrast, no evident antiepileptic responses or no responses at all were found in three patients when stimulation was either interrupted or when it was administered outside the hippocampus. Light microscopy analysis of the stimulated hippocampal tissue showed histopathological abnormalities attributable to the depth-electrode penetration damage or to the pial surface reaction to the subdural, Silastic electrode plate. However, no evident histopathological differences were found between the stimulated and nonstimulated hippocampal tissue. CONCLUSIONS: SAHCS appears to be a safe procedure that can suppress temporal lobe epileptogenesis with no additional damage to the stimulated tissue.

Adult↗
PubMed1999

Circulating levels of endothelial function are modulated by dietary monounsaturated fat.

BACKGROUND: For the most part, the benefits of monounsaturated-rich diets (MUFA-diet) have been related to their action on plasma lipid levels. However other non-lipidic effects could also be involved in their protective effects. One of these involves the decrease in plasma levels of plasminogen activator inhibitor type 1 (PAI-1), the main inhibitor of fibrinolysis. Given that the PAI-1 is of endothelial origin, one hypothesis is that the MUFA-diet could protect against CHD by modulating some endothelial components. METHODS AND RESULTS: Healthy male subjects (n = 25) received three different consecutive diets, each lasting 28 days: a low fat NCEP-I-diet, with 28% calories as fat, 10% saturated fat (SAT), 12% monounsaturated (MUFA) and 6% polyunsaturated (PUFA); a MUFA-diet, with 38% calories as fat, 10% SAT, 22% MUFA and 6% PUFA; and a SAT rich-diet (SAT-diet), with 38% calories as fat, 20% SAT, 12% MUFA and 6% PUFA. After each dietary period, the plasma lipid profile was determined, including total cholesterol, HDL cholesterol, LDL cholesterol, total triglyceride, apo A1, apo B plasma levels and conjugated diene formation, after incubation of LDL particles with Cu 5 microM/l. Endothelial products measured in plasma were von Willebrand factor (vWF), E-selectin, Thrombomodulin and Tissue Factor Pathway Inhibitor (TFPI) levels. We observed a decrease in vWF, PAI-1 and TFPI plasma levels and an increase in lag time of conjugated diene formation after the MUFA-diet. There was a positive correlation between the decreases in TFPI and vWF and the changes in total cholesterol, LDL-C, apo B plasma levels. The decrease in TFPI was negatively correlated with the increase in lag time of conjugated diene formation. PAI-1 plasma levels were positively correlated with total cholesterol, LDL-C and triglycerides and negatively correlated with HDL-C. CONCLUSIONS: Consumption of a Mediterranean-type MUFA-diet produces a decrease in plasma levels of vWF, TFPI and PAI-1 plasma levels in young healthy males. Given that these substances are of endothelial origin, one could suggest that the MUFA of the diet has a beneficial effect on endothelial function resulting in protective changes against thrombogenesis.

Adult↗
PubMed1999

Allogeneic bone marrow transplantation vs chemotherapy for the treatment of childhood acute lymphoblastic leukaemia in second complete remission (revisited 10 years on).

In 1989 we carried out a trial comparing allogeneic BMT to chemotherapy (CT) in 76 children with relapsed acute lymphoblastic leukaemia (ALL). Ten years on we have clinically revised outcome to firmly establish the role of each treatment, to analyse the importance of length of first remission and to provide long-term actuarial results for disease-free survival (DFS) and relapse rate in each group. For 21 patients within the transplantation group, probability of DFS and relapse are 42.8 +/- 10.8% and 40.2 +/- 11.7% (s.e.), respectively. In the chemotherapy group, probability of DFS is 10.0 +/- 4.74% (P = 0.001) and probability of relapse 87.5 +/- 5.2% (P = 0.0004). These results strongly reflect those at initial analysis, confirming a key role of BMT in the management of ALL in second remission. Moreover, on univariate analysis only two factors influenced DFS: treatment group and length of first complete remission (less or more than 30 months from first CR). Thus, it seems clear that the best therapeutic option in early relapse is BMT, whereas DFS in late relapse is at the limit of significance (P = 0.07), with a higher relapse rate in the CT group. Although encouraging results using intensified rotational combination chemotherapy have been published, prospective randomised studies are needed to assess with certainty the best therapeutic option in these patients.

Adolescent↗
PubMed1999

Cortical stimulation and epileptic seizure: a study of the potential risk in primates.

OBJECTIVE: The recent successful development of chronic stimulation of the motor cortex as a treatment for neuropathic and central pain does not exclude the possibility of eventual side effects, such as epileptic seizure or a lowering of the epileptic threshold. This study evaluates the behavioral and electroencephalographic impact of this treatment in three normal monkeys. RESULTS: None of the monkeys presented epileptic behavior or abnormal electroencephalographic activity at parameters of stimulation currently used in clinical series, i.e., frequency and pulse duration of approximately 40 Hz and 90 microseconds, respectively, and an intensity just under the threshold for inducing muscle twitch in painful areas. Higher intensities did, however, induce reversible epileptic seizure. There was, nonetheless, no modification of the epileptic threshold, because even after these seizures, intermittent light stimulation elicited no abnormal electroencephalographic activity. CONCLUSION: It thus seems that motor cortex stimulation does not induce epileptic complications when the classic clinical criteria of stimulation are respected. Nevertheless, it would be wise to subject candidates for implantation to intermittent light stimulation before and after a period of stimulation to ascertain the innocuousness of the cortical stimulation.

Animals↗
PubMed1999

Increased levels of tissue factor mRNA in mononuclear blood cells of patients with primary antiphospholipid syndrome.

Antiphospholipid antibodies (aPL) may stimulate tissue factor (TF) expression in cultured endothelial cells and monocytes, but there are discrepancies as to the expression of TF in the patients with antiphospholipid syndrome (APS). By using reverse transcription and polymerase chain reaction amplification, we have analysed TF mRNA accumulation in freshly isolated mononuclear blood cells (MBC) of 14 patients with primary APS (PAPS) and six normal controls. TF mRNA accumulation was low or absent in uncultured MBC from all normal controls, but was elevated in uncultured MBC from nine of the patients as well as in normal MBC incubated with 100 ng/ml lipopolysaccharide (LPS). Mean levels of TF mRNA, as measured by densitometry, were higher in MBC from patients (N = 14) than in those from controls (N = 6, P = 0.009), and in MBC from patients with a history of thrombosis (N = 9) than in those from patients without thrombosis (N = 5, P = 0.02). Uncultured MBC of patients with thrombosis accumulated TF mRNA at similar levels to LPS-treated normal MBC. Increased levels of TF mRNA were found in eight of ten patients with conventional aPL (ie, anti-cardiolipin antibodies [aCL] and/or lupus anticoagulant [LA]) and little if any accumulation of TF mRNA was observed in three of four patients without aPL at the time of study. These data strongly suggest that circulating monocytes of many patients with PAPS are subjected to an up-regulated TF expression that may well explain their prothrombotic state. Although the presence or absence of TF mRNA in MBC was associated with, respectively, the presence or absence of conventional aPL in 11 of the 14 patients studied, our study cannot exclude the involvement of factors other than aCL or LA in inducing TF expression.

Adult↗
PubMed1998

Comprehensive multimodality blood conservation: 100 consecutive CABG operations without transfusion.

BACKGROUND: Despite the recent introduction of a number of technical and pharmacologic blood conservation measures, bleeding and allogeneic transfusion remain persistent problems in open heart surgical procedures. We hypothesized that a comprehensive multimodality blood conservation program applied algorithmically on the basis of bleeding and transfusion risk would provide a maximum, cost-effective, and safe reduction in postoperative bleeding and allogeneic blood transfusion. METHODS: One hundred consecutive patients undergoing coronary artery bypass grafting were prospectively enrolled in a risk factor-based multimodality blood conservation program (MMD group). To evaluate the relative efficacy and safety of this comprehensive approach, comparison was made with a similar group of 90 patients undergoing coronary artery bypass grafting to whom the multimodality blood conservation program was not applied but in whom an identical set of transfusion guidelines was enforced (control group). To evaluate the cost effectiveness of the multimodality program, comparison was also made between patients in the MMD group and a consecutive series of contemporaneous, diagnostic-related group-matched patients. RESULTS: One hundred consecutive patients in the MMD group underwent coronary artery bypass grafting without allogeneic transfusion. This compared favorably with the control population in whom a mean of 2.2 +/- 6.7 units of allogeneic blood was transfused per patient (34 patients [38%] received transfusion). In addition, the volume of postoperative blood loss at 12 hours in the control group was almost double that of the MMD group (660 +/- 270 mL versus 370 +/- 180 mL [p < 0.001]). Total costs for the MMD group in each of the three major diagnostic-related groups were equivalent to or significantly less than those in the consecutive series of diagnostic-related group-matched patients. CONCLUSIONS: Comprehensive risk factor-based application of multiple blood conservation measures in an optimized, integrated, and algorithmic manner can significantly decrease bleeding and need of allogeneic transfusion in coronary artery bypass grafting in a safe and cost-effective manner.

Algorithms↗
PubMed1998

Effect of fentanyl and naloxone on a thalamic induced painful response in intractable epileptic patients.

Acute high-frequency (60/s) high-intensity (2,100-2,300 microA) stimulation of the mesial, caudal and inferior portion of the centromedian thalamic region within or close to the parafascicular nucleus produced a sharp, intense, cramp-like painful response localized to the face and shoulder (medial stimulation) or arm and hand (lateral stimulation) contralateral to the stimulation site in 4 intractable epileptic patients in whom depth electrodes had been implanted as a part of a neuroaugmentive procedure for seizure control. This thalamic induced painful response was always accompanied by objective clinical signs (facial gesticulation and contraction of the corresponding muscles) during thalamic stimulation and significant increments in EEG, EKG and respiratory frequencies and EMG muscular tonus from 10 s before to 10 s after thalamic stimulation. Opioid agonists (fentanyl 5.0 microg/kg) and antagonists (naloxone 3.5 microg/kg) were administered to induce and regulate a state of neuroleptanalgesia used for the subcutaneous internalization of the chronic stimulation systems. Under these conditions, we observed that fentanyl greatly attenuated and naloxone increased the intensity of the painful response, as well as the EEG, somatic and vegetative parameters evaluating such a painful response. Differences were significant when one compares the changes in response to electrical stimulation in EEG, EKG, respiration and EMG after the administration of fentanyl (decrease p = 0.001) and naloxone (increase p = 0.01) compared to those obtained after the administration of saline or no drugs during baseline recordings. These data suggest that this thalamic induced painful response is mediated by inhibition or activation of the morphine receptors of the thalamic cells primarily related to the pain process.

Adult↗
PubMed1997

In-laboratory removal of femoral sheath following protamine administration in patients having intracoronary stent implantation.

Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation.

Anticoagulants↗
PubMed1997

Comparison of bezafibrate versus lovastatin for lowering plasma insulin, fibrinogen, and plasminogen activator inhibitor-1 concentrations in hyperlipemic heart transplant patients.

Accelerated coronary artery disease is the most serious obstacle to long-term survival in heart transplant recipients. Hyperlipemia, hyperinsulinism, and changes in endothelial cell hemostatic function have been implicated in cardiac allograft vascular disease. Both lovastatin and bezafibrate are safe, effective, and well tolerated therapies for hyperlipidemia. Our study compares the effect of these lipid-lowering drugs in 21 patients with post-heart transplantation hyperlipidemia on different risk factors related to insulin resistance syndrome. Patients were given the same diet for 3 months, then randomized to lovastatin or bezafibrate for a period of 8 weeks, and crossed over to an additional 8 weeks of either bezafibrate or lovastatin. Baseline parameters were also compared with those of a control group of healthy subjects and after both periods of pharmacologic treatment. Transplant patients had higher insulin (35 +/- 3 vs 24 +/- 3 microIU/L), fibrinogen (298 +/- 15 vs 261 +/- 14 mg/dl), and plasminogen activator inhibitor-1 (PAI-1) (17 +/- 2 vs 11.7 +/- 2 arbitrary units/ml) plasma levels than controls. Significant decreases in insulin (-37 +/- 3%), fibrinogen (-12 +/- 4%), and PAI-1 plasma levels (-18 +/- 12%) were only observed after bezafibrate treatment. In conclusion, bezafibrate decreases plasma insulin, fibrinogen, and PAI-1 in hyperlipidemic heart transplant recipients.

Bezafibrate↗
PubMed1997

Characterization of tissue factor expression on the human endothelial cell line ECV304.

The endothelial cell line ECV304 is a spontaneously transformed cell line established from human umbilical vein. The characterization of tissue factor (TF) expression by ECV304 cells has been accomplished in this study. ECV304 cells expressed both TF mRNA and antigen (TFag) constitutively. In ECV304 cell lysates, the levels of TFag (1.4+/-0.3 ng of TFag/10[6] cells) were considerably higher than in THP-1 monocytoid cells (0.07+/-0.03 ng of TFag/10[6] cells). TFag was also detected on the ECV304 cell surface by flow cytometric studies. In binding analyses, 3.5+/-0.7 x 10(4) molecules of TF per cell were estimated, similar to the amounts found in ECV304 cell lysates (2.9+/-0.6 x 10(4) molecules/cell), suggesting that all TFag was translocated to the cell surface. Phorbol myristate acetate (PMA) stimulation of ECV304 cells resulted in an increase of TF mRNA levels, which was abrogated when gene transcription was impaired, suggesting a transcriptional regulation of the TF gene by PMA. In contrast, TFag was not elevated by PMA-stimulation, indicating the existence of additional posttranscriptional mechanisms. Thus, ECV304 cells constitute a singular endothelial cell model for exploring the regulation of TF expression.

Antibodies, Monoclonal↗
PubMed1997

Thrombosis in primary antiphospholipid syndrome: a pivotal role for monocyte tissue factor expression.

OBJECTIVE: The antiphospholipid syndrome (APS) is a disorder of recurrent thrombosis, pregnancy loss, and thrombocytopenia associated with the production of anticardiolipin antibodies (aCL) and lupus anticoagulant (LAC). The mechanisms of thrombus formation remain unknown. Tissue factor (TF), an inducible cell glycoprotein, is a major initiator of coagulation in vivo. The present study was therefore undertaken to investigate TF expression and procoagulant activity on monocytes from patients with primary APS and its correlation with thrombotic events. METHODS: Three groups of patients were studied: group 1 comprised 23 primary APS patients with thrombosis, group 2 consisted of 10 primary APS patients without thrombosis, and group 3 contained 20 patients with thrombosis but without antiphospholipid antibodies. Twenty age- and sex-matched healthy blood donors were used as controls (group 4). Anticardiolipin antibodies were measured by enzyme-linked immunosorbent assay (ELISA) and LAC by standard methodology. Cell surface expression of TF on monocytes was assessed by flow cytometry. The amount of TF in cell lysates (TF(Ag)) and soluble TF(Ag) plasma levels were analyzed by ELISA, and the TF-related procoagulant activity (PCA-TF) on intact cells and cell lysates by a chromogenic assay. Levels of the cytokines that influence TF production, i.e., tumor necrosis factor alpha (TNF alpha) and interleukin-1beta (IL-1beta), were determined by ELISA. RESULTS: Cell surface expression of TF was increased in group 1 (mean +/- SEM 50.2 +/- 4% positive cells) compared with group 2 (14.6 +/- 1.6%), group 3 (16.8 +/- 3.7%), and group 4 (14.1 +/- 1.6%). TF(Ag) levels were also elevated in group 1 (215.8 +/- 11.2 pg/10(6)) compared with group 2 (150.8 +/- 15.2), group 3 (101.4 +/- 14.8), and group 4 (80.32 +/- 5.5). PCA-TF on intact cells and cell lysates was significantly increased in group 1 (148.8 +/- 16.3 units/10(5) lysate cells, compared with 54.5 +/- 11.5, 38.6 +/- 9.7, and 22.5 +/- 3.1 in groups 2, 3, and 4, respectively). Among group 1 patients, there was a significant increase in the degree of TF expression in those positive for IgG aCL, but not in those positive for IgM aCL or LAC. TNF alpha and IL-1beta plasma levels did not differ significantly between any of the groups. CONCLUSION: These results suggest that monocyte TF expression is directly involved in the pathogenesis of thrombotic complications in patients with the primary APS.

Adult↗
PubMed1997

Electrocortical and behavioral responses produced by acute electrical stimulation of the human centromedian thalamic nucleus.

Incremental, desynchronizing and spike-wave electrocortical responses and concomitant symptoms to acute electrical stimulation of the centromedian thalamic nucleus (CM) were studied in 12 patients with intractable complex partial and tonic-clonic generalized seizures. Low-frequency (6/s), 320-800 microA stimulation of the caudal-basal and central portions of CM elicited incremental recruiting and augmenting-like responses with a bilateral regional scalp distribution, with emphasis at the ipsilateral frontal (recruiting) and central (augmenting) regions, while ventral-basal CM stimulation elicited primary-like responses with a focal distribution at the ipsilateral parietal region. High-frequency (60/s), 320-800 microA stimulation of caudal-basal and central, but not ventral-basal CM, elicited EEG desynchronization and a slow negative shift of the EEG baseline with scalp distribution similar to that showed by recruiting- and augmenting-like responses. Neither incremental nor desynchronization EEG responses were accompanied by evident patient sensory or motor responses. Low-frequency (3/s), high-intensity (30 V = 2400 microA) combined stimulation of the right CM and left non-specific mesencephalic ascending pathways elicited a response similar to the typical absence attack with all EEG and clinical ingredients: S1, S2, P1 and W components of the individual spike-wave complex and generalized spike-wave discharges followed by sleep spindle EEG afterdischarges, accompanied by motionless stare, 3/s eye blinking, lip smacking and total failure to respond to visual stimuli in patients under a simple responding task.

Behavior↗
PubMed1997

Temporo-spacial correlations between cortical and subcortical EEG spike-wave complexes of the Idiopathic Lennox-Gastaut syndrome.

All-night EEG recordings of the interictal 2/s spike-wave complexes (SKW) from different cortical and subcortical regions were performed in 5 patients with atypical absences of the Idiopathic Lennox-Gastaut syndrome (ILGS), in whom multicontact depth electrodes were implanted in the centromedian thalamic region as a part of a neuroaugmentive procedure for seizure control. Since during slow wave sleep III cortical spike (S2) and subcortical negative spike (NSK) consisting of simple monophasic negative potentials appeared together with a ratio of almost 1:1 and with fixed temporal relations, it was possible to determine visually the differences in peak-to-peak intervals of S2 and NSK, as well as their amplitude distribution in different cortical and subcortical structures. It was found that the peak of subcortical NSK preceded by 35 ms that of cortical S2. In addition, subcortical NSK and cortical S2 potentials attained maximal amplitude at the mesencephalic-thalamic reticular and frontal cortical regions, respectively, from which amplitude of NSK and S2 decreased with distance to other subcortical and cortical regions. These data suggest that interictal 2/s SKW of the ILGS result from ascending reticular impulses impinging upon the frontal cortical neurons.

Brain↗
PubMed1997

C1-esterase inhibitor prevents early pulmonary dysfunction after lung transplantation in the dog.

The success of lung transplantation to a large extent depends on effective protection of the graft from ischemic injury after reperfusion. Although mechanisms have not been clarified, the pathologic findings of ischemic injury after reperfusion are similar to adult respiratory distress syndrome, a condition in which the blood coagulation contact system is activated. This study evaluates the effect of C1-esterase inhibitor (C1-INH), the main inhibitor of the blood coagulation contact system, on short-term lung function in a dog model of orthotopic lung transplantation. Twelve lung transplantations were performed after 24 h of ischemic time. Dogs were randomly assigned to receive either vehicle (Control) or C1-INH. After the lung transplantation in the control group, Pao2 decreased by 84% and both the AaPO2 and the Qs/Qt% increased (340 and 530%, respectively, p < 0.01); these parameters remained unchanged in the C1-INH group. The hypoxemia observed in control animals was associated with decreased blood coagulation contact factors, complement consumption, increased expression of adhesion glycoproteins in leukocytes, and extensive intraalveolar and interstitial neutrophil infiltration. In contrast, C1-INH administration prevented hypoxemia, the decrease in blood coagulation contact factors, the activation of the complement system, the increase in expression of leukocyte adhesion molecules, and inflammatory cell infiltrate. This study has demonstrated that in a dog model of lung transplantation, the administration of C1-INH prevents early pulmonary dysfunction, and it suggests that activation of blood coagulation contact system and complement are important mechanisms causing ischemic injury after reperfusion.

Animals↗
PubMed1997

Tissue factor (TF) and urokinase plasminogen activator receptor (uPAR) and bleeding complications in leukemic patients.

Tissue factor (TF) and urokinase receptor (uPAR) are key cellular receptors triggering, respectively, coagulation and fibrinolysis. Bleeding complications among leukemic patients have been related to an abnormal expression of TF by blast cells and/or to an abnormal fibrinolytic response. In this study the expression of TF and uPAR has been assessed in 18 acute non-lymphoblastic and 8 lymphoblastic leukemic blast cells using several methodological approaches. TF mRNA was evaluated by in situ hybridization and TF and uPAR antigen were evaluated immunologically in cell lysates and on the cell surface by flow cytometry. In addition, TF-procoagulant activity was measured in coagulation-based assays. The reliability of these methods was corroborated in six leukemic cell lines of different lineages and states of maturation. Disseminated intravascular coagulation was detected in two M3 leukemia patients whose blast cells expressed high amounts of TF. Hyperfibrinolysis was detected in one M1 and two M2 patients, whose blast cells displayed a high content of uPAR antigen, but no TF. Furthermore, M5 leukemia blast cells expressed both TF and uPAR, although no hemostatic defects or bleeding complications were detected in these patients. Taken together, although a limited number of patients was included in this study, these data suggest that in leukemia patients exhibiting bleeding, either TF or uPAR are expressed by their blast cells. However, the presence of these receptors does not necessarily imply the existence of a hemostatic disorder.

Acute Disease↗