RESUMEN
Treatment with intensive chemotherapy regimens is frequently complicated by severe thrombocytopenia. During the period of severe thrombocytopenia, anticoagulant treatment is not uncommonly indicated for thromboembolic events or thromboprophylaxis in these patients. We report 10 hematological patients treated with intensive chemotherapy protocols that were anticoagulated with enoxaparin for catheter related central venous thrombosis and thromboprophylaxis. During the period of severe thrombocytopenia the dosages of enoxaparin were reduced and no major bleeding occurred. Based on our experience we suggest that reduced dosages of low molecular weight heparins may be used relatively safely during transient severe thrombocytopenia.
Asunto(s)
Anticoagulantes/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enoxaparina/uso terapéutico , Trombocitopenia/inducido químicamente , Trombosis/prevención & control , Adulto , Anciano , Anticoagulantes/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cateterismo Venoso Central/efectos adversos , Terapia Combinada , Enoxaparina/efectos adversos , Femenino , Neoplasias Hematológicas/sangre , Neoplasias Hematológicas/tratamiento farmacológico , Neoplasias Hematológicas/terapia , Hemorragia/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Células Madre de Sangre Periférica , Trombosis/sangre , Trombosis/etiologíaRESUMEN
Bleeding is the most serious adverse event of oral anticoagulants and is a major cause of morbidity and mortality in such patients. Rapid reversal of anticoagulation in bleeding patients or prior to urgent surgery is mandatory. The therapeutic options in these situations include administration of fresh frozen plasma (FFP), and recently of prothrombin complex concentrates (PCCs). However, viral safety and thrombogenicity of PCCs remain issues of concern. In the present study, we administered Octaplex, a new solvent/detergent (S/D) treated and nanofiltered PCC, to excessively anticoagulated bleeding patients or to anticoagulated patients facing urgent surgery. Ten excessively anticoagulated patients with major bleeding and 10 anticoagulated patients awaiting surgery (median age 72.5 (43-83) years, 9 females) received a median dose of 26.1 IU/kg body weight (BW) of Octaplex for reversal of anticoagulation. Response to Octaplex was rapid with decline of INR within 10 min after Octaplex administration (from 6.1+/-2. to 1.5+/-0.3). Clinical response was graded as good in most patients (85%) and as moderate in the rest. Octaplex administration was uneventful in all patients. Following Octaplex administration, a small increase in F1+2 levels was observed in bleeding patients, whereas D-dimer level did not change significantly. We conclude that Octaplex is effective and safe in situations where rapid reversal of anticoagulation is needed.
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Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Factores de Coagulación Sanguínea/administración & dosificación , Coagulantes/administración & dosificación , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hemorragia/sangre , Hemorragia/diagnóstico , Humanos , Israel , Masculino , Persona de Mediana Edad , Federación de Rusia , Resultado del TratamientoRESUMEN
BACKGROUND: There is limited information about risk factors for venous thromboembolism (VTE) in acutely ill hospitalized general medical patients. METHODS: An international, randomized, double-masked, placebo-controlled trial (MEDENOX) has previously been conducted in 1102 acutely ill, immobilized general medical patients and has shown the efficacy of using a low-molecular-weight heparin, enoxaparin sodium, in preventing thrombosis. We performed logistic regression analysis to evaluate the independent nature of different types of acute medical illness (heart failure, respiratory failure, infection, rheumatic disorder, and inflammatory bowel disease) and predefined factors (chronic heart and respiratory failure, age, previous VTE, and cancer) as risk factors for VTE. RESULTS: The primary univariate analysis showed that the presence of an acute infectious disease, age older than 75 years, cancer, and a history of VTE were statistically significantly associated with an increased VTE risk. Multiple logistic regression analysis indicated that these factors were independently associated with VTE. CONCLUSIONS: Several independent risk factors for VTE were identified. These findings allow recognition of individuals at increased risk of VTE and will contribute to the formulation of an evidence-based risk assessment model for thromboprophylaxis in hospitalized general medical patients.
Asunto(s)
Hospitalización , Tromboembolia/epidemiología , Trombosis de la Vena/epidemiología , Enfermedad Aguda , Anciano , Anticoagulantes/uso terapéutico , Comorbilidad , Enoxaparina/uso terapéutico , Femenino , Insuficiencia Cardíaca/epidemiología , Humanos , Modelos Logísticos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Respiratoria/epidemiología , Factores de Riesgo , Tromboembolia/prevención & control , Trombosis de la Vena/prevención & controlRESUMEN
Background: Patients carrying variant CYP2C9 alleles are prone to bleeding complications under standard warfarin treatment. Our aim was to test the feasibility of warfarin therapy in patients with severe, inherited CYP2C9 deficiency. Methods: CYP2C9 genotypes and clinical characteristics were compared retrospectively in patients who maintain stable anticoagulation on low or regular doses of warfarin. Results: In the low-dose (10.5+/-2.9 mg/week) group (N=16), we identified six (37.6%) patients with severe CYP2C9 deficiency and three each with *2/*3 and *3/*3 genotypes as compared to none in the standard dose (39.2+/-17.9 mg/week) group (N=17). Warfarin dose (mg/week) was correlated with genotype in all patients as follows: *1/*1 (N=14) dose=33.6+/-19.4; *1/*2 (N=9) dose=30.4+/-21.6; *1/*3 (N=4) dose=15.3+/-10.7; *2/*3 (N=3) dose=10.6+/-3.6; *3/*3 (N=3) dose=7.3+/-3.1. Age and frequency of concurrent warfarin potentiating medication administration were higher in the low-dose group than in the standard dose group of patients. Conclusions: Warfarin treatment is feasible in individuals with severe, inherited CYP2C9 deficiency. Dose requirement was correlated with CYP2C9 genotype and possibly affected by age and concurrent intake of interfering drugs. Prospective studies are needed to test the feasibility and cost effectiveness of using algorithms based on these parameters for adjusting initial warfarin dose to meet individual needs.
RESUMEN
The general safety and efficacy of intravenous immunoglobulin (IGIV) as treatment for idiopathic thrombocytopenic purpura (ITP) has been well-studied. The current study compares the safety and efficacy of a novel IGIV (IGIV-C; Gamunex, 10%) with a licensed solvent/detergent-treated product (IGIV-S/D; GamimuneN, 10%) in treatment of ITP. Ninety-seven pediatric and adult patients with acute and chronic ITP were treated in a multi-center, prospective, randomized, double-blind parallel group, non-inferiority trial at 26 international sites. Baseline data (age, duration of ITP, platelet counts, previous treatment) were comparable between groups. Patients were treated with 1 g/kg/day of IGIV-C or IGIV-S/D for 2 days. The primary end-point, proportion of patients whose platelet counts increased from >/=20 x 10(9)/L to >/=50 x 10(9)/L within 7 days after dosing, was achieved by 35/39 (90%) and 35/42 (83%) of patients treated with IGIV-C and IGIV-S/D, respectively. A secondary endpoint, maintaining platelet counts >/=50 x 10(9)/L for >/=7 days, was achieved by 29/39 (74%) of IGIV-C and 25/42 (60%) IGIV-S/D treated patients. Compared with IGIV-S/D, fewer patients treated with IGIV-C received corticosteroids beyond day 7 (p = 0.02). Efficacy was independent of the presence of isoantibodies or blood type, supporting mechanisms of effect different from anti-D treatments. Adverse events were generally mild and occurred with similar frequency in each group. Viral safety monitoring for HIV, HCV, HBV and Parvovirus B19 showed no seroconversions on study. In conclusion, IGIV-C is as safe and efficacious as IGIV-S/D in treatment of ITP.
Asunto(s)
Inmunoglobulinas Intravenosas/administración & dosificación , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Calidad de Vida , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Caprilatos/administración & dosificación , Caprilatos/uso terapéutico , Caprilatos/toxicidad , Niño , Preescolar , Método Doble Ciego , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunoglobulinas Intravenosas/toxicidad , Incidencia , Lactante , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Esterilización , Resultado del Tratamiento , Virosis/transmisiónRESUMEN
The Medical Patients with Enoxaparin (MEDENOX) trial was a randomized, placebo-controlled study that defined the risk of venous thromboembolism (VTE) in acutely ill, immobilized, general medical patients and the efficacy of the low-molecular-weight heparin, enoxaparin, in preventing thrombosis. We performed a post-hoc analysis to evaluate the effect of 40 mg enoxaparin once daily on MEDENOX patient outcome in different types of acute medical illness (heart failure, respiratory failure, infection, rheumatic disorder and inflammatory bowel disease) and pre-defined risk factors (chronic heart and chronic respiratory failure, age, immobility, previous VTE and cancer). The primary outcome was the occurrence of documented VTE between days 1 and 14. The relative risk reduction [95% confidence intervals (CI)] for VTE comparing 40 mg enoxaparin with placebo in the subgroups were: acute heart failure, 0.29 (95% CI, 0.10-0.84); acute respiratory failure, 0.25 (95% CI, 0.10-0.65); acute infectious disease, 0.28 (95% CI, 0.09-0.81); and acute rheumatic disorder, 0.48 (95% CI, 0.11-2.16). The relative risk reduction for VTE in the pre-defined risk factor subgroups were: chronic heart failure, 0.26 (95% CI, 0.08-0.92); chronic respiratory failure, 0.26 (95% CI, 0.10-0.68); age, 0.22 (95% CI, 0.09-0.51); immobility, 0.53 (95% CI, 0.14-1.72); previous VTE, 0.49 (95% CI, 0.15-1.68); and cancer, 0.50 (95%o CI, 0.14-1.72). The beneficial effects of enoxaparin extend to a wide range of acutely ill medical patients.
Asunto(s)
Anticoagulantes/uso terapéutico , Enoxaparina/uso terapéutico , Trombosis de la Vena/prevención & control , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Insuficiencia Cardíaca/sangre , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Movimiento/efectos de los fármacos , Estudios Multicéntricos como Asunto , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Obesidad/sangre , Obesidad/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Respiratoria/sangre , Insuficiencia Respiratoria/tratamiento farmacológico , Tromboembolia/tratamiento farmacológico , Tromboembolia/prevención & control , Resultado del Tratamiento , Várices/sangre , Várices/tratamiento farmacológico , Trombosis de la Vena/tratamiento farmacológico , CaminataRESUMEN
Severe obstetric complications, including preeclampsia, intrauterine growth retardation, abruptio placentae, and stillbirth, constitute a major cause of maternal and perinatal morbidity and death. The etiology of these severe obstetric complications is still unknown. However, the frequent finding of structural and thrombotic changes in placental capillaries, which lead to inadequate fetomaternal circulation and decreased placental perfusion, and the high prevalence of heritable or acquired risk factors for thrombosis found in women with these complications strongly suggest a cause-and-effect relationship. This review describes the recent findings on the association between these obstetric complications and the various thrombophilias, and recent therapeutic approaches. Aspirin, which was regarded as the drug of choice for the prevention of such obstetric complications, has proved to be ineffective in a large clinical trial. The encouraging observations on the efficacy of low-molecular-weight heparins, which are also included in the recently published guidelines of The American College of Chest Physicians, are summarized in this review. However, controlled clinical trials are still necessary to allow the development of better clinical standards.
Asunto(s)
Complicaciones Cardiovasculares del Embarazo/etiología , Trombofilia/complicaciones , Aspirina/uso terapéutico , Femenino , Heparina de Bajo-Peso-Molecular/uso terapéutico , Humanos , Embarazo , Complicaciones del Embarazo/etiología , Complicaciones Cardiovasculares del Embarazo/tratamiento farmacológico , Complicaciones Cardiovasculares del Embarazo/prevención & control , Trombofilia/tratamiento farmacológicoRESUMEN
Splenectomy is the only treatment of ITP known to have "curative" effects in a substantial fraction of patients. However, the true long-term outcome is uncertain and controversial because published series have not adjusted for the duration of follow-up. This IRB-approved retrospective study included all patients with ITP who underwent splenectomy between 1988-1993 at three major medical centers and required a minimum postoperative 5-year follow-up. Complete response (CR) was defined as all postsplenectomy platelet counts >150 x 10(9)/L without treatment; partial response (PR) as platelet counts > or =50 x 10(9)/L without treatment; and failure as platelet counts <50 x 10(9)/L or receiving therapy after splenectomy. Seventy-five patients identified with ITP underwent splenectomy from 1988 to 1993. Three patients died prior to 5-year follow-up, and 56 of the 72 patients (78%) were evaluable with follow-up for five years or longer, median 7.5 years. The immediate postoperative complete remission rate was 77%; 57% of patients have remained in prolonged CR. Thirty-seven patients (66%) have not required any therapy after splenectomy. Eight patients had platelet counts >150 x 10(9)/L for 4-8.5 years before relapsing; no clear plateau was attained in the remission curve. There was no operative mortality. Ten patients (18%) reported minor postoperative bleeding episodes. No life-threatening infections, significant heart disease, or pulmonary hypertension developed after splenectomy in the 434 patient-years of follow-up. This study helps to define the long-term results of splenectomy for ITP.
Asunto(s)
Púrpura Trombocitopénica Idiopática/terapia , Esplenectomía/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Supervivencia sin Enfermedad , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/complicaciones , Púrpura Trombocitopénica Idiopática/mortalidad , Inducción de Remisión , Estudios Retrospectivos , Esplenectomía/mortalidad , Resultado del TratamientoRESUMEN
To study the regulation of acetylcholinesterase (AChE) gene expression in human brain tumors, 3' splice variants of AChE mRNA and potentially relevant transcription factor mRNAs were labeled in primary astrocytomas and melanomas. AChE-S and AChE-R mRNA, as well as Runx1/AML1 mRNA accumulated in astrocytomas in correlation with tumor aggressiveness, but neither HNF3beta nor c-fos mRNA was observed in melanoma and astrocytomas. Immunohistochemistry demonstrated nuclear Runx1/AML1 and cellular AChE-S and AChE-R in melanomas, however, only AChE-S, and not the secreted AChE-R variant, was retained in astrocyte tumor cells. Runx1/AML1 revealed weak linkage with ACHE promoter sequences, yet enhanced ACHE gene expression in co-transfected COS1 cells. The p300 co-activator and the ACHE promoter's distal enhancer facilitated this effect, which was independent of much of the Runx1/AML1 trans-activation domain. Surprisingly, GASP, a fusion product of green fluorescence protein (GFP) and ASP(67), a peptide composed of the 67 C-terminal amino acid residues of AChE-S, localized to COS1 cell nuclei. However, GARP, the corresponding fusion product of GFP with a peptide having the 51 C-terminal residues of AChE-E or GFP alone, remained cytoplasmic. Runx1/AML1 exhibited improved nuclear retention in GASP-expressing COS1 cells, suggesting modulated nuclear localization processes. Together, these findings reveal brain tumor-specific regulation of both expression and cellular retention of variant ACHE gene products.
Asunto(s)
Acetilcolinesterasa/genética , Neoplasias Encefálicas/genética , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Acetilcolinesterasa/metabolismo , Empalme Alternativo , Secuencia de Aminoácidos , Astrocitoma/enzimología , Astrocitoma/genética , Secuencia de Bases , Neoplasias Encefálicas/enzimología , Variación Genética , Proteínas Fluorescentes Verdes , Humanos , Proteínas Luminiscentes/genética , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , ARN Mensajero/genética , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
In order to differentiate between the contributions of cellular and plasmatic factors to the elevated aggregation in pregnancy-induced hypertension (PIH), we determined RBC aggregation in autologous plasma and in plasma-free medium. The aggregation was determined as a function of shear stress, to evaluate the strength of the intercellular interaction. These procedures were applied to RBC from PIH women (n=20), normotensive pregnant (NTP) women (n=15), and non-pregnant (control) women (n=15). The average aggregate size (AAS) in plasma for PIH, NTP and control RBC was 38.7+/-3.2, 28.4+/-3.0, and 11.5+/-2.2 (P<0.05, between the three groups), respectively. For the same groups, the aggregation in plasma-free standard medium was 17.3+/-2.0, 12.0+/-1.2 and 10.0+/-1.6 (P<0.05 between PIH and the other two groups), respectively. The contribution of plasma to the elevated aggregation was 75% and 88% for PIH and NTP respectively. Tau(S50), the shear stress required to singly disperse 50% of the RBC population, in plasma and in standard medium, was about the same for PIH and NTP, and both were markedly higher than that for control RBC. These findings suggest that the increased aggregation of RBC from women with PIH, over those at of NTP women, may be due largely to changes in cellular factors and the increased aggregability has the potential to affect blood flow mainly in low-flow states such as in the placental intervillous space.
Asunto(s)
Eritrocitos/citología , Preeclampsia/sangre , Complicaciones Cardiovasculares del Embarazo/sangre , Adolescente , Adulto , Presión Sanguínea , Índice de Masa Corporal , Agregación Celular , Femenino , Humanos , Embarazo , Estrés MecánicoRESUMEN
The efficacy of oral anticoagulants (OAC) in reducing the incidence of stroke in elderly patients with atrial fibrillation (AF) has been well documented. The intensity of OAC therapy and deviations in the prothrombin time (PT) are the strongest risk factor for bleeding complications in elderly patients. The aim of this study was to evaluate a more rigorous regulation of OAC by the use of a portable whole blood PT-monitor (CoaguChek) in elderly patients with AF (age 65-80 years). The study group consisted of 20 patients, of whom 17 were evaluable, which were trained to use to CoaguChek monitor and adjust their anticoagulant dose for 12 months. The control group, 20 patients matched for age, gender and the duration of OAC treatment, were tested in an anticoagulant clinic and their OAC dose was adjusted by a physician. To validate the PT-monitor results, the patients performed a total of 129 simultaneous venous blood PT tests at various time points. The correlation coefficient R(2) was 0.707 indicating the accuracy of the CoaguChek results. The self-managed patients perform more frequent measurements 46 +/- 8.9 vs. 15.7 +/- 3.1 PT tests per patient. They demonstrated a within the therapeutic range INR in 80.5% of the tests (95% confidence interval, 76.5-84.1%) as compared to 72.4% (95% confidence interval, 68.5-76.5%) in the control group (p = 0.057). The median value for all CoaguChek International Normalized Ratio (INR) recordings was within therapeutic range in the self-management group as well as in the control group. There were fewer INR results below or above the therapeutic range in the study group. None of the patients had hemorrhagic or thrombotic events during the study. Overall, the study group expressed high satisfaction from using the home monitor. We conclude that home PT monitoring and self-management of OAC are feasible in a motivated population of elderly patients with atrial fibrillation and are probably cost effective.
Asunto(s)
Anticoagulantes/uso terapéutico , Fibrilación Atrial/tratamiento farmacológico , Relación Normalizada Internacional/instrumentación , Tiempo de Protrombina , Administración Oral , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/economía , Fibrilación Atrial/complicaciones , Fibrilación Atrial/economía , Análisis Costo-Beneficio , Estudios de Factibilidad , Femenino , Hemorragia/inducido químicamente , Hemorragia/prevención & control , Humanos , Relación Normalizada Internacional/economía , Masculino , Cooperación del Paciente , Educación del Paciente como Asunto , Satisfacción del Paciente , Estudios Prospectivos , Autoadministración/psicología , Accidente Cerebrovascular/prevención & controlRESUMEN
OBJECTIVE: Hematopoietic stress responses involve increases in leukocyte and platelet counts, implying the existence of stress responsive factors that modulate hematopoiesis. Acetylcholinesterase (AChE) is expressed in mammalian neurons and hematopoietic cells. In brain, it responds to stress by mRNA overexpression and alternative splicing, yielding the rare stress-associated "readthrough" AChE-R variant protein. This led us to explore the hematopoietic involvement of AChE-R and its cleavable C-terminal peptide ARP. MATERIALS AND METHODS: AChE mRNA variants were labeled in CD34(+) hematopoietic progenitor cells by in situ hybridization. ARP expression was detected by multicolor flow cytometry. Bromo-deoxyuracil incorporation and viable cell counts served to evaluate the proliferative effects of ARP and suppressive effects of the AChE antisense oligonucleotide AS1 on CD34(+) cells. RESULTS: The distal enhancer, proximal promoter, and first intron of the human AChE gene include consensus binding sites for hematopoietically active and stress-induced transcription factors. CD34(+) cells from human cord blood were found to express all three variant AChE mRNAs, having different intracellular distributions. ARP was found in 5 to 15% of adult peripheral blood, bone marrow, and fetal CD34(+) cells (both committed CD38(+) and uncommitted CD38(-)) and in acute myeloid leukemia blasts. Externally supplied ARP by itself facilitated the proliferation of CD34(+) cells in an antisense suppressible manner. When combined with early-acting cytokines, ARP enhanced survival and expansion of CD34(+) cells up to 28 days in culture. CONCLUSIONS: Our findings support ARP, the C-terminal peptide of AChE-R, as a new hematopoietic growth factor that may promote the myelopoietic expansion and thrombopoiesis characteristic of stress and may be used to enhance the efficiency of ex vivo expansion for bone marrow transplantation.
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Acetilcolinesterasa/genética , División Celular/fisiología , Variación Genética , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/enzimología , Estrés Fisiológico/genética , Adulto , Antígenos CD/sangre , Antígenos CD34/sangre , Sangre Fetal/citología , Feto/fisiología , Citometría de Flujo , Sustancias de Crecimiento/farmacología , Humanos , Inmunofenotipificación , Hibridación in Situ , Recién Nacido , Oligodesoxirribonucleótidos Antisentido , Fragmentos de Péptidos/farmacología , Estrés Fisiológico/enzimologíaRESUMEN
OBJECTIVE: Umbilical cord blood (CB) provides an alternative source of hematopoietic progenitor cells for transplantation; however, prolonged thrombocytopenia remains a major obstacle due to the low numbers of megakaryocyte progenitor (Mk-prog) cells and their subsequent delayed engraftment. In this study, we improved techniques for enrichment, cryopreservation, and ex vivo expansion of Mk-prog cells from CB. MATERIALS AND METHODS: CB mononuclear cells (MNC) were isolated and Mk-prog enriched by sedimentation on gelatin followed by centrifugation with Ficoll-Hypaque and cryopreserved. The capacity of MNC to produce Mk-prog cells, assessment of CD34(+) and Mk-prog expansion in liquid culture, and analysis of the cell populations by flow cytometry were studied in cryopreserved separated CB and compared to whole CB and freshly separated samples. RESULTS: Excellent viability of greater than 85% was maintained after cryopreservation of separated CB. The number of colony-forming Mk-prog, myeloid, and erythroid progenitor cells did not decrease with cryopreservation. Flow cytometric analysis of cryopreserved cells revealed significant removal of the residual red blood cells while maintaining complete recovery of CD34(+), CD41(+) (Mk), myeloid, and T and B cells compared to noncryopreserved CB cells. There was no difference in the ability of separated cryopreserved MNC CB cells to be expanded in short-term liquid cultures. CONCLUSIONS: The conditions defined here for cryopreservation of gelatin/Ficoll-Hypaque separated CB, followed by ex vivo expansion of MNC, allowed complete recovery of proliferating CD41(+), CD34(+), Mk-prog cells, and other hematopoietic progenitors. Mk-prog cell expansion just before the scheduled transplantation is easily applicable by this technically simple and economical procedure that requires only an aliquot of red cell cell-depleted MNC to be separated from the CB unit before cryopreservation.
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Conservación de la Sangre , Separación Celular/métodos , Criopreservación , Sangre Fetal/citología , Células Madre Hematopoyéticas/citología , Megacariocitos/citología , Trasplante de Células Madre , Diferenciación Celular , Linaje de la Célula , Supervivencia Celular , Células Cultivadas/citología , Ensayo de Unidades Formadoras de Colonias , Diatrizoato , Ficoll , Citometría de Flujo , Gelatina , Células Madre Hematopoyéticas/clasificación , Humanos , Recién NacidoRESUMEN
Several experimental systems have been applied to investigate the development of new blood vessels. Angiogenesis can be followed ex-vivo by culturing explants of rat aorta 'rings' in biomatrix gels. This angiogenesis system was modified for the study of viral vector mediated gene transfer, using adenovirus, vaccinia- and retroviral vectors. Two modifications were introduced to the model in order to facilitate efficient viral mediated gene transfer, (i) placing the aorta ring on top of a thin layer of collagen such that the angiogenic tissue will be accessible to the viral vector; and (ii) infection of the aorta rings prior to embedding them into the collagen matrix. While adenovirus and vaccinia vectors infected efficiently the aorta rings they induced cell death. Subsequent gene transfer experiments were, therefore, carried with retroviral vectors containing vascular endothelial growth factor (VEGF) and the beta-interferon (IFN) genes. Overexpression of VEGF enhanced significantly microvessel sprouting, while overexpression of IFN-beta induced an antiviral effect. The experimental system described in this study can facilitate the application of other viral vectors to the study of genes that may regulate the complex angiogenic process and thereby open new avenues for vascular gene therapy.
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Aorta/virología , Técnicas de Transferencia de Gen , Vectores Genéticos , Neovascularización Fisiológica , Virus/genética , Adenoviridae/genética , Animales , Aorta/fisiología , Técnicas de Cultivo/métodos , Factores de Crecimiento Endotelial/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Interferón beta/genética , Linfocinas/genética , Ratas , Retroviridae/genética , Virus Vaccinia/genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial VascularRESUMEN
Increased red cell aggregability might have unfavorable rheological effects in the microcirculation. It has been suggested that thrombolysis-related hypofibrinogenemia might be associated with a reduced erythrocyte adhesiveness/aggregation. We followed the reduction in erythrocyte adhesiveness/aggregation using a simple slide test and image analysis that measures the spaces that are formed between the aggregated erythrocytes. A significant (p = 0.01) reduction in the degree of erythrocyte adhesiveness/aggregation was noted in patients with acute myocardial infarction who received thrombolysis as opposed to individuals with Braunwald Class IIIB unstable angina who had normal fibrinogen concentrations. No change was found in the Westergren erythrocyte sedimentation rate, which is an indirect method to detect changes in aggregability of red blood cells. The present study shows the superiority of using a direct measurement of red blood cell adhesiveness/aggregation. This extremely rapid, cheap and almost bedside methodology to detect changes in erythrocyte adhesiveness/aggregation might be useful to detect changes of hemorheological relevance following thrombolysis.
Asunto(s)
Eritrocitos/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológico , Estreptoquinasa/uso terapéutico , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , Sedimentación Sanguínea , Adhesión Celular/efectos de los fármacos , Agregación Celular/efectos de los fármacos , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Humanos , Masculino , Métodos , Persona de Mediana Edad , Infarto del Miocardio/sangre , Estadística como AsuntoRESUMEN
Thromboembolic disease is a rare, but important, complication of pregnancy that remains a leading non-obstetric cause of maternal death. The prevention and management of venous thromboembolism (VTE) in pregnant women is a complex area of medicine: a balance must be found between protecting the health of the mother and minimizing the risk to the unborn fetus. Until now, unfractionated heparin has been regarded as the drug of choice for the prevention and treatment of VTE during pregnancy. However, because of its significant side effects (osteoporosis and heparin-induced thrombocytopenia), the inconvenient mode of administration and need for monitoring, unfractionated heparin is now being replaced by low-molecular-weight heparin (LMWH). There is a convincing body of clinical evidence from well-designed studies and prospective case series that supports the efficacy and safety of LMWH in pregnant women. There are also encouraging observations on the efficacy of LMWH in the prevention of severe obstetric complications, which are frequently associated with inherited or acquired thrombophilias. The recently-published guidelines of The American College of Chest Physicians (ACCP), summarized in this review, allows the development of higher clinical standards. However, there is concern over the greater cost of LMWH compared with unfractionated heparin and oral anticoagulants, and cost-effectiveness studies are needed.
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Anticoagulantes/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Complicaciones Cardiovasculares del Embarazo/tratamiento farmacológico , Tromboembolia/tratamiento farmacológico , Aborto Habitual/prevención & control , Analgesia Epidural/efectos adversos , Anticoagulantes/efectos adversos , Densidad Ósea/efectos de los fármacos , Dalteparina/uso terapéutico , Femenino , Guías como Asunto , Heparina de Bajo-Peso-Molecular/efectos adversos , Heparina de Bajo-Peso-Molecular/farmacocinética , Humanos , Incidencia , Embarazo , Complicaciones Cardiovasculares del Embarazo/epidemiología , Factores de Riesgo , Trombofilia/complicaciones , Trombofilia/tratamiento farmacológico , Trombofilia/etiología , Warfarina/uso terapéuticoRESUMEN
Heparanase is a heparan-sulfate-degrading endoglycosidase that has important roles in various biological processes, including angiogenesis, wound healing and metastatsis. Human heparanase is synthesized as a 65 kDa latent precursor, which is proteolytically processed into a highly active 50 kDa form. Extracellular heparanase is found in various tissues and is utilized by both normal cells and metastatic cancer cells to degrade heparan sulfate moieties in basement membranes and extracellular matrices. This study characterizes the processing and trafficking events associated with cellular activation of extracellular heparanase. We show that primary human fibroblasts are capable of binding and converting the 65 kDa heparanase precursor into its highly active 50 kDa form, concomitantly with its cytoplasmic accumulation. Heparanase uptake depends on the actin cytoskeleton integrity, resulting in a prolonged storage of the enzyme, mainly in endosomal structures. Heparanase endocytosis and its proteolytic activation are independent processes, indicating that heparanase cleavage is a cell surface event. Heparin completely inhibits heparanase endocytosis but only partially inhibits its association with the cells, suggesting that cell surface heparan sulfate moieties play a specific role in its endocytosis. Cellular binding and uptake of extracellular heparanase control its activation, clearance rate and storage within the cells.
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Matriz Extracelular/enzimología , Fibroblastos/enzimología , Glucuronidasa/metabolismo , Procesamiento Proteico-Postraduccional , Western Blotting , Células Cultivadas , Endocitosis/efectos de los fármacos , Activación Enzimática , Fluorescencia , Heparina/farmacología , Humanos , Proteínas de la Membrana/metabolismo , Transporte de Proteínas , Proteínas de Transporte VesicularRESUMEN
OBJECTIVE: To determine the risk of thrombophilias in women with unexplained intrauterine fetal deaths (IUFD). METHODS: All women with IUFD at 27 weeks' gestation or greater were initially assessed during a period of 26 months. Subjects with multiple pregnancies, congenital anomalies, intrauterine infection, chorioamnionitis, immune hydrops, diabetes mellitus, previous thromboembolism, and severe hypertensive disease were excluded. The remaining 40 women with unexplained IUFD (study group) were matched for age and ethnicity with 80 healthy women who had at least one normal pregnancy (control group). All participants were tested at least 2 months after delivery for mutations of factor V Leiden, prothrombin gene, methylenetetrahydrofolate reductase, and for deficiencies of protein S, protein C, and antithrombin III. They were also tested and found to be negative for anticardiolipin antibodies. RESULTS: The gestational age at delivery and birth weight were significantly lower in the study group. The prevalence of inherited thrombophilias was 42.5% in the study group compared with 15% in the control group (odds ratio 2.8, 95% confidence interval 1.5, 5.3, P =.001). The prothrombin mutation and protein S deficiency rates were significantly higher in the study group (odds ratio 2.3, 95% confidence interval 1.3, 4.0, and odds ratio 3.2, 95% confidence interval 2.4, 4.1, respectively). CONCLUSION: Third-trimester IUFD is significantly associated with thrombophilias. These findings suggest that thrombophilia work-ups should be part of IUFD investigations and may have therapeutic and prognostic implications in future pregnancies.
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Muerte Fetal/etiología , Trombofilia/complicaciones , Trombofilia/genética , Adulto , Estudios de Casos y Controles , Femenino , Edad Gestacional , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Embarazo , Resultado del Embarazo , Tercer Trimestre del Embarazo , Prevalencia , Factores de Riesgo , Trombofilia/epidemiologíaRESUMEN
BACKGROUND: Abdominal surgery for cancer carries a high risk of venous thromboembolism, but the optimal duration of postoperative thromboprophylaxis is unknown. METHODS: We conducted a double-blind, multicenter trial in which patients undergoing planned curative open surgery for abdominal or pelvic cancer received enoxaparin (40 mg subcutaneously) daily for 6 to 10 days and were then randomly assigned to receive either enoxaparin or placebo for another 21 days. Bilateral venography was performed between days 25 and 31, or sooner if symptoms of venous thromboembolism occurred. The primary end point with respect to efficacy was the incidence of venous thromboembolism between days 25 and 31. The primary safety end point was bleeding during the three-week period after randomization. The patients were followed for three months. RESULTS: The intention-to-treat analysis of efficacy included 332 patients. The rates of venous thromboembolism at the end of the double-blind phase were 12.0 percent in the placebo group and 4.8 percent in the enoxaparin group (P=0.02). This difference persisted at three months (13.8 percent vs. 5.5 percent, P=0.01). Three patients in the enoxaparin group and six in the placebo group died within three months after surgery. There were no significant differences in the rates of bleeding or other complications during the double-blind or follow-up periods. CONCLUSIONS: Enoxaparin prophylaxis for four weeks after surgery for abdominal or pelvic cancer is safe and significantly reduces the incidence of venographically demonstrated thrombosis, as compared with enoxaparin prophylaxis for one week.
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Anticoagulantes/administración & dosificación , Enoxaparina/administración & dosificación , Complicaciones Posoperatorias/prevención & control , Embolia Pulmonar/prevención & control , Trombosis de la Vena/prevención & control , Neoplasias Abdominales/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/efectos adversos , Método Doble Ciego , Enoxaparina/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pélvicas/cirugía , Estudios Prospectivos , Embolia Pulmonar/mortalidad , Tromboembolia/mortalidad , Tromboembolia/prevención & control , Factores de TiempoRESUMEN
Chronic myeloid leukemia (CML), in most of the cases, is the molecular consequence of the t(9,22) translocation, resulting in the Philadelphia (Ph) chromosome and the creation of the fusion gene BCR-ABL. The fusion gene is translated to the protooncogen BCR-ABL, a constitutively activated tyrosine kinase that is linked to the malignant transformation. Thus, this tyrosine kinase became an attractive target for drug design. The development of the novel investigational drug STI 571 is based on its potent and selective ability to inhibit this fusion tyrosine kinase. In preclinical studies, STI 571 selectively inhibited the growth of CML cells that carry the Ph chromosome. In this review we discuss the drug development and design, its mechanism of action, the preclinical studies and the results of phase I and II clinical trials.