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1.
Biomaterials ; 4(3): 218-21, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6615986

RESUMEN

Three poly(amido-amine)s of similar structure in the form of highly hydrophilic crosslinked resins, have been prepared, and tested for their heparin-adsorbing capacity at physiological pH. They showed different capacities, and their capacities were related to their basicities. One of the same polymers was grafted on the surface of glass microspheres. After treatment, it was shown that the microspheres could adsorb significant amounts of heparin. In all cases most of the adsorbed heparin was hardly eluted with saline, plasma, or blood, but could be recovered by eluting with 0.1 M NaOH. The resins were found to have some haemolytic properties, but no haemolysis was observed with the grafted microspheres.


Asunto(s)
Heparina , Nylons , Resinas Sintéticas , Adsorción , Vidrio , Heparina/aislamiento & purificación , Concentración de Iones de Hidrógeno , Microesferas
2.
Biomed Pharmacother ; 49(3): 141-4, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7647285

RESUMEN

Purine nucleotides were studied in human peripheral blood lymphocytes from normal subjects and patients with chronic B-cell lymphocytic leukemia (B-CLL). Nucleotide content was determined by high performance liquid chromatography (HPLC). The overall rate of purine nucleotide synthesis was measured following the incorporation of 14C-formate into the nucleotides of a lymphocytic suspension. Results indicate a substantially reduced rate of purine nucleotide metabolism.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/metabolismo , Linfocitos/metabolismo , Nucleótidos de Purina/metabolismo , Anciano , Anciano de 80 o más Años , Cromatografía Líquida de Alta Presión , Humanos , Persona de Mediana Edad
3.
Tumori ; 77(2): 112-7, 1991 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-2048222

RESUMEN

The authors studied the behavior of some enzymes involved in purine nucleotide metabolism in human peripheral blood lymphocytes from normal and B-cell chronic lymphocytic leukemia subjects. Determinations were made with radiochemical methods associated with high performance liquid chromatography. Results indicated a marked increase in de novo purine synthesis enzymes, particularly those of the "inosinic branch point". The latter were absent in normal lymphocytes, whereas they were well evident in leukemic lymphocytes, with the exception of AMP-S synthetase. Whereas the enzymes of the "salvage pathway" were spared in comparison to other proteins, those of the "catabolic pathway" significantly decreased. The authors discuss the possibility that such enzymes may be used as tumor markers.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/enzimología , Nucleótidos de Purina/metabolismo , AMP Desaminasa/análisis , Adenina Fosforribosiltransferasa/análisis , Anciano , Anciano de 80 o más Años , Humanos , Hipoxantina Fosforribosiltransferasa/análisis , Persona de Mediana Edad
5.
Recenti Prog Med ; 80(10): 564-5, 1989 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-2602641

RESUMEN

The Authors describe a case of multiple myeloma characterized by extraskeletal spread at the testis and at the subcutaneous soft tissues. They evaluate the pathogenetic hypothesis and the prognostic significance.


Asunto(s)
Mieloma Múltiple/patología , Neoplasias de los Tejidos Blandos/patología , Neoplasias Testiculares/patología , Humanos , Masculino , Persona de Mediana Edad
12.
Am J Hematol ; 52(1): 14-20, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8638606

RESUMEN

Patients with polycythemia vera (PV) or essential thrombocythemia (ET) show a high frequency of thrombosis. The reduction of hematocrit after phlebotomy and normalization of platelet counts do not completely eliminate thrombotic risk. Some preliminary studies reported a reduction in the concentration of natural anticoagulants (NA) in this group of patients. For this reason we evaluated protein S (PS) total antigen, antithrombin III (AT III), and protein C (PC) activity in 81 patients with chronic myeloproliferative disorders (33 with PV and 48 with ET). Data were compared with those obtained in 70 healthy sex- and age-matched subjects. Fifty-seven percent of patients (46 out of 81) showed one or more thrombotic episodes at diagnosis or during follow-up. Interestingly, we found a NA deficit in 43.5% of patients with thrombosis versus only 5.7% in the group of patients without thrombosis. These results may suggest new interpretations about the pathogenesis of thrombosis in PV or ET patients.


Asunto(s)
Deficiencia de Antitrombina III , Policitemia Vera/sangre , Deficiencia de Proteína C , Deficiencia de Proteína S/etiología , Trombocitemia Esencial/sangre , Trombosis/etiología , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Diabetes Mellitus/epidemiología , Susceptibilidad a Enfermedades , Femenino , Estudios de Seguimiento , Hematócrito , Humanos , Hipercolesterolemia/epidemiología , Hipertensión/epidemiología , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Policitemia Vera/complicaciones , Policitemia Vera/tratamiento farmacológico , Embolia Pulmonar/sangre , Embolia Pulmonar/epidemiología , Embolia Pulmonar/etiología , Embolia Pulmonar/fisiopatología , Riesgo , Fumar/epidemiología , Trombocitemia Esencial/complicaciones , Trombocitemia Esencial/tratamiento farmacológico , Trombosis/sangre , Trombosis/epidemiología , Trombosis/fisiopatología
13.
Haematologica ; 78(3): 185-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8375750

RESUMEN

A patient with M5b acute nonlymphoblastic leukemia (ANLL) and a 47,XXX del(11) (q23) karyotype is described. Partial remission was obtained after treatment with daunorubicin, arabinosylcytosine and VP-16. Subsequently, two courses of chemotherapy for resistant ANLL were administered without achieving complete remission. Abnormalities of chromosome 11 are typical of M4 and M5 ANLL. X trisomy is one of the most common human aneuploidia; however, correlation with increased incidence of hematological neoplasia has not been described.


Asunto(s)
Cromosomas Humanos Par 11 , Leucemia Mieloide Aguda/genética , Trisomía , Cromosoma X , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Cariotipificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Persona de Mediana Edad
14.
Eur J Haematol ; 53(4): 213-7, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7957805

RESUMEN

Polycythemia vera (PV) is a chronic myeloproliferative disease. The use of recombinant alpha 2a Interferon (IFN) therapy in this disease is a novel approach. We applied Fourier-transform infrared microspectroscopy (FT-IR-M) to investigate the behavior and therapeutic responsiveness of PV patients treated with IFN. A spectroscopic parameter (A1/A2) was used, corresponding to the ratio of the integrated areas of the bands at 1080 cm-1 and at 1540 cm-1 due to nucleic acids and proteic components, respectively, calculated on the spectra of single megakaryocytes (MKs). In previous studies, we have pointed out that MKs in PV have a surprisingly strong myeloproliferative impulse when compared to MKs from other chronic myeloproliferative diseases. Nine patients out of the 11 studied exhibited a satisfactory responsiveness to the IFN treatment. Ten patients were evaluated by the A1/A2 parameter. In 8 of these, a good agreement was seen between this parameter and the laboratory data commonly used for the assessment of this disease. The infrared parameter, which we propose, proves to be an original, reliable method for the evaluation of recombinant alpha 2a IFN responsiveness in this disease.


Asunto(s)
Interferón-alfa/uso terapéutico , Megacariocitos/química , Policitemia Vera/sangre , Policitemia Vera/terapia , Recuento de Células Sanguíneas , Hematócrito , Hemoglobinas/análisis , Humanos , Interferón alfa-2 , L-Lactato Deshidrogenasa/sangre , Proteínas Recombinantes , Espectroscopía Infrarroja por Transformada de Fourier/métodos
15.
Boll Soc Ital Biol Sper ; 66(4): 349-55, 1990 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-2390225

RESUMEN

Adenylic acid (AMP) deaminase is a "catabolic enzyme" involved in nucleotide degradation, transforming AMP into inosinic acid (IMP). We present a simple method for the determination of the enzyme activity, which combines high sensitivity with requirement of low quantities of lymphocytes. Human lymphocytes were isolated with a Lymphocyte Separation Medium from FLOW and sonicated. After centrifugation at 2,000 rpm x 10 min and treatment with Norit A, the cells were incubated at 37 degrees C with ATP 0.8 mM and 14C-AMP 0.1 mM (specific activity 12 microCi/mumole) in potassium phosphate 100 mM (pH 7.4). 14C-IMP and 14C-AMP were separated through HPLC by an isocratic elution, with 20 mM KH2PO4 (pH 5.5) at a 1.5 ml/min flow rate. Identification of the nucleotides was carried out through retention time, coelution with internal standards: their evaluation by determining the radioactivity of the collected peaks. The enzyme activity is decreased in patients affected by CLL: the decrease is evident only when data are referred to the single cells and not when they are referred to the protein.


Asunto(s)
AMP Desaminasa/análisis , Inosina Monofosfato/análisis , Nucleótidos de Inosina/análisis , Linfocitos/enzimología , Nucleótido Desaminasas/análisis , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimología , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Purinas/metabolismo
16.
Boll Soc Ital Biol Sper ; 66(5): 449-55, 1990 May.
Artículo en Italiano | MEDLINE | ID: mdl-1975748

RESUMEN

At the "inosinic branch point", inosinic acid (IMP) can be channelled either to guanylic acid (GMP) or to adenylic acid (AMP). The 4 enzymes involved in these processes are IMP-dehydrogenase (IMP-DH) and GMP synthetase for the formation of GMP and adenylosuccinate (AMP-S) synthetase and lyase for the formation of AMP. The Authors study the behavior of these enzymes in peripheral blood lymphocytes from normal and leukemic patients. The cells were isolated as previously reported. GMP synthetase was assayed with radiochemical method, IMP-DH and AMP-S synthetase with a radiochemical method coupled to HPLC, while AMP-S lyase was determined following the formation of AMP separated by AMP-S by HPLC, without using labelled precursors. Except for GMP synthetase, which was very low, no activity was detectable in normal lymphocytes; while AMP-S was absent also in leukemic cells, the remaining three activities were well evident. The results open the possibility of using the inosinic branch point enzymes as tumor markers.


Asunto(s)
Ligasas de Carbono-Nitrógeno , Inosina Monofosfato/metabolismo , Nucleótidos de Inosina/metabolismo , Leucemia Linfocítica Crónica de Células B/enzimología , Linfocitos/enzimología , Adenilosuccinato Liasa/metabolismo , Adenilosuccinato Sintasa/metabolismo , Humanos , IMP Deshidrogenasa/metabolismo , Ligasas/metabolismo
17.
Boll Soc Ital Biol Sper ; 66(5): 457-62, 1990 May.
Artículo en Italiano | MEDLINE | ID: mdl-2397107

RESUMEN

The Authors present a procedure for the determination of adenine phosphoribosyltransferase (APRT) and hypoxanthine phosphoribosyltransferase (HPRT) in lymphocytes which exhibits high sensitivity and requires low quantities of lymphocytes. 5 normal subjects and 4 patients affected by chronic lymphocytic leukemia (CLL) were considered. Human lymphocytes were prepared and treated as previously reported. To the incubation mixtures buffered with 50 mM TRIS-HCl pH 7.4 either 14C-adenine or 14C-hypoxanthine was added: after deproteinization and neutralization we followed the formation of either 14C-adenylic acid (AMP) or 14C-inosinic acid (IMP) by HPLC. A Supelcosil C18 5 microns (250 X 4.5 mm) column was used: IMP was eluted with 20 mM KH2PO4 pH 5.5 while AMP with a linear gradient to 40% B in 20 min., where A was 20 mM KH2PO4 pH 5.5 and B methanol/water 60:40. Evaluation of AMP and IMP formed was carried out by determination of the radioactivity of the collected peaks. The values of APRT in leukemic patients were enhanced when referred to the proteins and those of HGPRT decreased: the Authors propose to complete the study evaluating the intracellular content of adenine and hypoxanthine.


Asunto(s)
Adenina Fosforribosiltransferasa/metabolismo , Hipoxantina Fosforribosiltransferasa/metabolismo , Leucemia Linfocítica Crónica de Células B/enzimología , Linfocitos/enzimología , Pentosiltransferasa/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Humanos , Purinas/metabolismo
18.
Boll Soc Ital Biol Sper ; 65(11): 1097-103, 1989 Nov.
Artículo en Italiano | MEDLINE | ID: mdl-2560926

RESUMEN

Phosphoribosyl-1-pyrophosphate (PRPP) amidotransferase is the "key anabolic enzyme" of purine nucleotide synthesis; PRPP synthetase connects the pentose cycle with the same pathway. We have studied their behavior in 5 control subjects and in 8 affected by CLL. Determination of PRPP amidotransferase was carried out through the evaluation of 14C-glutamic acid (released by 14C-glutamine) in the incubation mixture. PRPP synthetase was followed by adding ATP and ribose 5-phosphate to the incubation mixtures, and by evaluating the PRPP formed through the release of CO2 in a coupled reaction. In the case of PRPP-amidotransferase, our values are in the range reported in the literature: in patients affected by CLL, the enzyme activity is much higher and the increase is more evident when values referred to the patients, than when to the cells. Our values of PRPP synthetase are consistent with those of Peters and Veerkamp, but no definite conclusion is possible in the case of leukemic patients.


Asunto(s)
Amidofosforribosiltransferasa/metabolismo , Leucemia Linfocítica Crónica de Células B/enzimología , Linfocitos/enzimología , Pentosiltransferasa/metabolismo , Fosfotransferasas/metabolismo , Ribosa-Fosfato Pirofosfoquinasa/metabolismo , Humanos , Leucemia Linfocítica Crónica de Células B/sangre
19.
Br J Haematol ; 88(4): 770-7, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7819101

RESUMEN

We investigated the prognostic significance of interleukin-10 (IL-10) and soluble interleukin-2 receptor (sIL-2r) levels in the pretreatment serum of 105 individuals with newly-diagnosed aggressive non-Hodgkin's lymphoma (NHL). Commercially available enzyme-linked immunoassay kits were used for cytokine and receptor measurements. Detectable levels of IL-10 were found in 42 (40%) patients at diagnosis, with no correlation with clinico-haematological parameters, but in no control samples (P < 0.001). Pretreatment concentrations of sIL-2r were markedly increased in individuals with NHL when compared to controls (2614 +/- 893 U/ml v 219 +/- 65 U/ml, P < 0.001), patients with stage III/IV presenting higher values than those with stage II disease (3885 +/- 1196 U/ml v 1732 +/- 646 U/ml, P < 0.001). No single parameter was associated with the achievement of complete remission, but the combination of elevated IL-10 and of sIL-2r greater than 3000 U/ml selected a subset of patients with a high probability of failing induction therapy (P < 0.001). Life-table analysis also indicated that patients with these characteristics have a significantly shorter event-free survival. In a multivariate analysis the combination of IL-10 with sIL-2r was found to have greater predictive strength than the combination of IL-10 with beta 2-microglobulin. We conclude that IL-10 and sIL-2r measurements can be expected to improve existing methods of risk assignment in aggressive NHL.


Asunto(s)
Biomarcadores de Tumor/sangre , Interleucina-10/sangre , Linfoma no Hodgkin/sangre , Receptores de Interleucina-2/análisis , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Recurrencia , Solubilidad
20.
Cancer ; 74(6): 1792-800, 1994 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8082082

RESUMEN

BACKGROUND: This study explores the ability of the combined detection of soluble IL-2 receptor (sIL-2r) and interleukin-10 (IL-10) to predict treatment failure in patients with aggressive non-Hodgkin's lymphoma (NHL) and to evaluate the modifications in cytokine measurements induced by the therapeutic administration of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF). METHODS: Serum levels of sIL-2r and IL-10 were measured serially in 93 patients with newly diagnosed aggressive NHL treated with four courses of a multiagent chemotherapy regimen. GM-CSF was administered subcutaneously in 39 of these patients from day +5 to day +18 after each chemotherapy course. RESULTS: Pretreatment levels of sIL-2r were greatly elevated in patients with NHL compared with control subjects (P < 0.001), significantly correlating with the Ann Arbor stage (P < 0.001) and beta 2-microglobulin (beta 2-m) concentrations (r = 0.552, P = 0.004). IL-10 was detected in 37 patients at diagnosis, with no correlation with clinicohematologic parameters, and was not detected in the control sample (P < 0.001). Cytokine and receptor levels progressively declined to normal ranges in responding patients, whereas they remained elevated in nonresponders. During administration of GM-CSF, the authors observed an increase of sIL-2r, whereas lower elevations were recorded for IL-10. However, on completion of the induction treatment, cytokine/receptor levels were comparable in patients with the same type of response, whether or not they had received GM-CSF. In the five patients who were investigated at relapse, the levels of sIL-2r, beta 2-m, and lactic dehydrogenase were found to be elevated. IL-10 concentrations were high in three of these patients: two already had detectable levels at presentation, whereas one tested positive only on recurrence. No single parameter was associated with response to therapy, but the combination of elevated IL-10 and sIL-2r concentrations greater than 3000 U/ml resulted in a subset of eight patients who failed induction chemotherapy (P < 0.001). In addition, six of eight patients with high IL-10 and beta 2-m concentrations greater than 3.3 mg/l had an unfavorable outcome (P = 0.003). A multivariate regression model was used to identify sIL-2r (P = 0.004) and beta 2-m (P = 0.043) as the covariates that amplified the prognostic ability of IL-10. CONCLUSIONS: sIL-2r and IL-10 measurements provide valuable information for better management of patients with NHL as markers to monitor disease activity and as prognostic indicators.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/uso terapéutico , Interleucina-10/análisis , Linfoma no Hodgkin/sangre , Receptores de Interleucina-2/análisis , Adolescente , Adulto , Femenino , Humanos , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Recurrencia , Inducción de Remisión
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