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1.
Environ Technol ; 29(6): 709-20, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18702297

RESUMO

The management of polluted road runoff water is an important issue in environmental protection. A strategy could be to perform local depuration by infiltration into the soils of the embankment, but knowledge for designing such systems is lacking. This study aims at discussing the relevant soil properties, by estimating the long-term depuration of road runoff water infiltrating into the sandy soil embankment of the A9 highway in Wallis, Switzerland. This was done by estimating the heavy metals (HM) mass balance of two sites 23 and 12 years old, respectively. The accumulated HM were estimated by soil and GB analyses. The HM input was estimated by average water quality and traffic. The results were discussed using two-dimensional simulation of infiltration and a 14 months in situ monitoring of the runoff from the pavement to the embankment and at the bottom of the embankment. The soil properties were appropriate for both small particle adsorption and filtration. A good match between input and stored pollutant charges was found, and the HM profiles accorded well with infiltration simulation and monitoring results, which showed that 80-100% of the runoff water infiltrated into the embankment. Replacement of the cracked concrete gutters by an infiltration channel made of similar soil is recommended. These results oppose the Swiss guidelines for road-polluted water infiltration, as much more clayey soils are recommended. These later soils are difficult to find in Switzerland, and may allow for preferential flow through macro pores, in contrast to the studied site.


Assuntos
Monitoramento Ambiental/métodos , Filtração/métodos , Poaceae , Solo/análise , Movimentos da Água , Poluentes Químicos da Água/análise , Água/química , Metais Pesados/análise , Poaceae/crescimento & desenvolvimento , Chuva , Suíça , Purificação da Água/métodos
2.
J Clin Invest ; 70(4): 707-15, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7119110

RESUMO

An electrophoretically fast-moving variant of the spectrin beta-chain was discovered in the erythrocyte membranes of a woman and her father who both exhibited elliptocytosis and mild hemolytic anemia. This abnormal beta'-subunit (Mr = 214,000) co-existed with a decreased normal beta-chain and represented about half of the total beta-chains in the membrane. In contrast to the spectrin beta-chain, the beta'-chain was phosphorylated neither in the membrane by endogenous protein kinases nor in solution by pure membrane casein kinase whether or not the spectrin was dephosphorylated by erythrocyte cytosolic spectrin phosphatase. The presence of the beta'-chain was associated with a defective self-association of spectrin dimer to form tetramer as manifested by: (a) an excess of spectrin dimer in the 4 degrees C spectrin crude extract, (b) a defective self-association of the spectrin dimer in the 37 degrees C crude spectrin extracts. Gel electrophoretic analysis of the tetramer and dimer species isolated from the proband's 4 degrees C extract showed that the tetramer contained trace amounts of the beta'-chain, whereas in contrast, a large proportion of beta'-chain was present in the dimer. These results demonstrated the responsibility of the beta'-chain for the defective reassociation of spectrin dimer into tetramer. The study of this abnormal spectrin confirms the participation of spectrin beta-chain in dimer-dimer association and strongly suggests that the phosphorylation sites of the normal beta-chain are located at the end of the molecule involved in the dimer-dimer interactions.


Assuntos
Eliptocitose Hereditária/sangue , Proteínas de Membrana/genética , Espectrina/genética , Adulto , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Eliptocitose Hereditária/genética , Membrana Eritrocítica/análise , Membrana Eritrocítica/metabolismo , Feminino , Variação Genética , Humanos , Substâncias Macromoleculares , Masculino , Pessoa de Meia-Idade , Fosforilação , Espectrina/metabolismo
3.
J Clin Invest ; 86(3): 909-16, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1975598

RESUMO

alpha I/74 hereditary elliptocytosis (HE) is a subgroup of HE in which patients exhibit an impaired self-association of spectrin dimers and an abnormal proteolytic cleavage of the alpha I domain of spectrin. We studied a family in which the proband presented with a severe neonatal hemolytic anemia with poikilocytosis. Biochemical analysis of erythrocytes from the proband and his family members allowed us to ascertain a diagnosis of homozygosity for alpha I/74 HE in the proband and heterozygosity in his parents and several of their offspring. Results of polymorphism linkage analysis suggested that the defect in this family was located in beta rather than alpha spectrin. We analyzed the 3' end of the beta-spectrin gene of the proband and detected a mutation that changes a codon for alanine to one for proline. Allele-specific oligomer hybridization on slot blots of DNA from other family members confirmed the presence of the mutation only in members heterozygous for the disorder. This is the first example of a point mutation in the beta-spectrin chain that is associated with defective spectrin dimer self-association and an abnormal proteolytic cleavage of the alpha chain. Based on this finding, we propose a model for the mechanism of interaction between the alpha- and beta-spectrin chains.


Assuntos
Eliptocitose Hereditária/genética , Espectrina/genética , Sequência de Aminoácidos , Sequência de Bases , Eletroforese em Gel Bidimensional , Ligação Genética , Humanos , Substâncias Macromoleculares , Dados de Sequência Molecular , Mutação , Oligonucleotídeos , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Conformação Proteica , Mapeamento por Restrição , Espectrina/ultraestrutura
4.
Cancer Res ; 44(9): 4137-9, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6589047

RESUMO

Superoxide dismutase (SOD), catalase, and glutathione peroxidase activities have been determined in red blood cells isolated from patients with acute myelogenous leukemia, chronic lymphocytic leukemia, Hodgkin's disease, lymphosarcoma, and various visceral cancers. In all investigated cases, both catalase and glutathione peroxidase were found to be in normal ranges of activity. In the group of patients with visceral cancers, SOD activity was found to be normal as well. In contrast, SOD activity was found to be significantly increased in red blood cells from patients with acute myelogenous leukemia and lymphoproliferative syndromes. This increase in superoxide level was not related to either reticulocytosis or hypochromic anemia. No relationship was found between the SOD level and the stage, the extension of the disease, or the presence of an inflammatory syndrome. The highest SOD levels were observed in untreated patients or during the early time period of the treatment. SOD levels further decrease as a function of the increase in the duration of the treatment. These results suggest an abnormality in the regulation of the expression of the SOD gene in the pluripotent stem cells.


Assuntos
Catalase/sangue , Eritrócitos/enzimologia , Glutationa Peroxidase/sangue , Neoplasias/enzimologia , Superóxido Dismutase/sangue , Doença de Hodgkin/enzimologia , Humanos , Leucemia Linfoide/enzimologia , Leucemia Mieloide Aguda/enzimologia , Linfoma não Hodgkin/enzimologia
5.
Biochim Biophys Acta ; 484(2): 348-52, 1977 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-911853

RESUMO

In the presence of SH group protectors, human leukocyte and platelet pyruvate kinases demonstrate biphasic kinetics with respect to the phosphoenolpyruvate substrate. SH group oxidation by oxidized glutathione reveals positive cooperativity kinetics for purified preparations of leukocyte and platelet pyruvate kinases. Complete reversal of the phenomenon may be obtained by incubation for several hours in dithiothreitol. This communication illustrates the existing relationships between enzyme conformation, the redox state of the SH groups, and the observed kinetics.


Assuntos
Plaquetas/enzimologia , Leucócitos/enzimologia , Piruvato Quinase/sangue , Ditiotreitol/farmacologia , Glutationa/farmacologia , Humanos , Cinética , Oxirredução , Fosfoenolpiruvato/metabolismo , Conformação Proteica , Relação Estrutura-Atividade
6.
Biochim Biophys Acta ; 860(2): 243-52, 1986 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-3638145

RESUMO

Band 3 protein of human erythrocyte membrane is phosphorylated on a tyrosine residue located near the NH2 terminal by an endogenous tyrosine kinase activity (Dekowski, S., Rybicki, A. and Drickamer, K. (1983) J. Biol. Chem. 258, 2750-2753). A tyrosine kinase phosphorylating the band 3 protein in situ has been extracted from ghosts by non-ionic detergent and partially characterized (Phan-Dinh-Tuy, F., Henry, J. and Kahn, A. (1985) Biochem. Biophys. Res. Commun. 126, 304-312). We have studied the properties of the tyrosine kinase activity which remains bound to the ghosts after detergent extraction using the 43 kDa fragment of protein 3 as substrate. This activity, solubilized from the detergent-resistant material at 0.25 M NaCl and concentrated by phosphocellulose and tyrosine-agarose chromatographies, remains linked to high molecular weight complexes. It is specific for tyrosine. Assayed with the purified 43 kDa fragment it requires the presence of Mn2+ which cannot be replaced by Mg2+. Its affinity for 43 kDa fragment is very high with a Km of 3.3 microM. ATP acts as a phosphoryl donor with a Km of 0.55 microM. The tyrosine kinase activity was not modified by insulin, DMSO, phorbol ester and epidermal growth factor, vanadate and xanthine derivatives. Polyamines spermidine and the polylysine are inhibitors in the presence of Mn2+ but not in the presence of Mg2+. Heparin is a competitive inhibitor of ATP. 2,3-Diphosphoglycerate is an inhibitor at physiological concentrations (Ki = 2 mM). Purified red cell actin is not phosphorylated by the tyrosine kinase. These properties distinguish the red cell membrane-bound tyrosine kinase from other tyrosine kinases extracted from normal cells.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Membrana Eritrocítica/enzimologia , Proteínas Tirosina Quinases/sangue , 2,3-Difosfoglicerato , Actinas/sangue , Trifosfato de Adenosina/metabolismo , Cromatografia , Citosol/metabolismo , Ácidos Difosfoglicéricos/farmacologia , Heparina/farmacologia , Humanos , Manganês/farmacologia , Fragmentos de Peptídeos/metabolismo , Fosforilação , Poliaminas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Especificidade por Substrato , Tirosina/metabolismo , Vanadatos , Vanádio/farmacologia
7.
Biochim Biophys Acta ; 438(2): 393-406, 1976 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-821529

RESUMO

L-type pyruvate kinase (ATP:pyruvate 2-O-phosphotransferase, EC 2.7.1.40) was highly purified from adult human liver. This purification included ammonium sulphate fractionation, DEAE-Sephadex batchwise absorption and two CM-Sephadex chromatographies with selective elution by ligands; in the former chromatography pyruvate kinase was eluted by ATP, in the latter one by phosphoenolpyruvate and fructose 1,6-diphosphate. The last step of the purification procedure involved a hydroxyapatite column chromatography. This purification procedure allowed us to obtain 3.6 mg of protein with a specific activity 190 I.U./mg, i.e. a 1200-fold purification with an overall yield of about 8%. This preparation was homogenous as judged by immunodiffusion, acrylamide and sodium dodecyl sulphate acrylamide gel electrophoresis. Anti L-type pyruvate kinase antibodies were obtained from rabbits and the antigenic properties of L-type pyruvate kinase were studied. The enzyme appeared to be a tetramer (molecular weight 220 000-240 000) with subunits of similar molecular weight about 60 000). Two interconvertible major forms were found by isoelectrofocusing in a sucrose gradient and in an acrylamide slab gel: one had an isoelectric point of 5.85 +/- 0.09 and was the major enzymatic form after incubation with fructose 1,6-diphosphate or high concentrations or SH reagents. The other form (isoelectric point 6.28 +/- 0.03) was the major form of L-type pyruvate kinase in liver crude extract, and after incubation of purified enzyme with a proteic fraction isolated from liver extract by ammonium sulphate precipitation.


Assuntos
Fígado/enzimologia , Piruvato Quinase/isolamento & purificação , Cromatografia de Afinidade , Humanos , Imunodifusão , Focalização Isoelétrica , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Substâncias Macromoleculares , Peso Molecular , Piruvato Quinase/imunologia , Piruvato Quinase/metabolismo
8.
Biochim Biophys Acta ; 481(1): 96-104, 1977 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-402946

RESUMO

Erythrocyte pyruvate kinase (ATP:pyruvate 2-0-phosphotransferase, EC 2.7.1.40) has been purified 40 000 times from human erythrocytes, according to an original method. The whole purification procedure included toluene extraction, ammonium sulphate fractionation, DEAE-Sephadex batchwise chromatography and affinity chromatography on a Dextran Blue-Sepharose column with specific elution by fructose 1,6-diphosphate. The final preparation had specific activity of 290 I.U./mg of proteins and the overall yield was about 30%. Pyruvate kinase showed only one protein band as judged by sodium dodecyl sulphate acrylamide gel electrophoresis. Pure enzyme was injected into rabbits and monospecific antiserum was obtained able to neutralize, per ml, 150 I.U. of erythocyte-type pyruvate kinase as well as of L-type enzyme. L-type and erythrocyte-type pyruvate kinases showed reactions of complete identity when tested in immunodiffusion against anti-erythrocyte type pyruvate kinase sera; in all cases a single precipitation line could be detected. L-type pyruvate kinase when mixed with anti-erythocyte pyruvate kinase serum suppressed all ability of that antiserum to react immunological with erythocyte enzyme. Finally the microcomplement fixation curves using anti-erythrocyte pyruvate kinase serum were identical for erythrocyte and L-type enzymes. From these results it appeared that no antigenic difference between L-type and erythocyte enzyme could be detected. Consequently the most likely hypothesis is that both these enzymes are coded by the same single gene, the slight electrophoretic differences between them being due to post-synthetic tissue-specific changes.


Assuntos
Eritrócitos/enzimologia , Piruvato Quinase/isolamento & purificação , Antígenos , Testes de Fixação de Complemento , Humanos , Imunodifusão , Métodos , Piruvato Quinase/imunologia
9.
Biochim Biophys Acta ; 647(1): 1-6, 1981 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-6271204

RESUMO

Hydrosoluble proteins extracted from human erythrocyte ghosts by dialysis at low ionic strength and alkaline pH contain a cyclic AMP-dependent protein kinase which phosphorylates in vitro the cytoskeleton components in crude extracts. Spectrin components 1 and 2, actin and protein band 4.1 undergo this cyclic AMP-dependent endogenous phosphorylation together with low molecular weight peptides solubilized with the cytoskeleton in hydrosoluble extract. However, pure spectrin and purified erythrocyte G-actin were not phosphorylated by purified cyclic AMP-dependent protein kinase from erythrocyte membrane. Purified G-actin when added free to crude extract does not undergo phosphorylation by the cyclic AMP-dependent protein kinase present in this extract. In contrast, purified cyclic AMP-dependent protein kinase added either to crude extract or to the purified cytoskeleton complex (spectrin, actin and protein band 4.1), phosphorylates spectrin, actin and protein band 4.1. We can conclude that (1) cyclic AMP-dependent phosphorylation of red cell cytoskeleton occurs in vitro only when the cytoskeleton components are in a complexed form; (2) red cell actin, like other cellular actins, may be phosphorylated by cyclic AMP-dependent protein kinase but only in the oligomeric form and not in the G form.


Assuntos
Proteínas Sanguíneas/metabolismo , Proteínas do Citoesqueleto , Eritrócitos/metabolismo , Proteínas de Membrana/metabolismo , Neuropeptídeos , Proteínas Quinases/sangue , Actinas/metabolismo , AMP Cíclico/farmacologia , Membrana Eritrocítica/enzimologia , Humanos , Fosforilação , Espectrina/metabolismo , Ultracentrifugação
10.
Biochim Biophys Acta ; 904(2): 201-6, 1987 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-3663669

RESUMO

Following our previous observation that the oldest normal red blood cells were the most adherent to human cultured endothelial cells, we attempted to simulate this age-related adherence. Among all the membrane modifications experienced by erythrocytes during their life-span, loss of sialic acids has attracted considerable attention. Using two different preparations of neuraminidase, we performed a sialic acid depletion on the youngest erythrocytes to reach a sialic acid content similar to that observed in physiologically aged erythrocytes. These pretreated youngest cells displayed limited increase in the adhesiveness to endothelial cells, lower than that found with intact oldest cells. To obtain an adhesiveness of pretreated cells similar to that of naturally aged cells, it was necessary to exceed 80% of sialic acid depletion. At this extent of desialation, modifications of the electrophoretic pattern of glycophorins were observed as well as the appearance of peanut agglutinin reactivity which were never found in physiologically aged erythrocytes. Therefore, the sialic acid loss cannot be considered as being a single determinant factor of the naturally aged red cell adhesiveness.


Assuntos
Endotélio Vascular/citologia , Envelhecimento Eritrocítico , Membrana Eritrocítica/fisiologia , Eritrócitos/citologia , Ácidos Siálicos/sangue , Adesão Celular , Separação Celular/métodos , Células Cultivadas , Centrifugação com Gradiente de Concentração , Feminino , Hemaglutinação , Humanos , Lectinas , Aglutinina de Amendoim , Reticulócitos/citologia , Veias Umbilicais
11.
Biochim Biophys Acta ; 445(3): 537-48, 1976 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-974098

RESUMO

Several molecular forms of human glucose-6-phosphate dehydrogenase (D-glucose-6-phosphate:NADP+ 1-oxidoreductase, EC 1.1.1.49) corresponding to different stages of post-synthetic modifications have been purified from human leukocytes. The various enzyme forms were different in their specific activity, their kinetic properties and their isoelectrofusing pattern. The molecular weight of the subunits of the different forms was not modified. The changes in the electrofocusing pattern were not due to modifications of the N-terminal ends, the oxidation of thiol groups or the non-covalent fixation of an acid molecule upon the enzyme. Carboxypeptidase B cleaved a C-terminal lysine from the different enzyme forms and shifted the isoelectric point of the different enzyme active bands towards the acid pH. The different enzyme forms studied here seemed to result from the action upon 'native glucose-6-phosphate dehydrogenase' of 'modifying factors' especially abundant in some leukemic granulocytes. The modifying factors did not seem to be consumed during the 'modification' of glucose-6-phosphate dehydrogenase. Moreover, the storage for one year of unmodified enzyme resulted in changes in its electrofocusing pattern similar to those quickly induced by the 'modifying factors'. Consequently it appears that the modifying factors are catalysts of the modification of special residues of glucose-6-phosphate dehydrogenase. The hypothesis that this modification involves the deamination of asparagine or glutamine residues is put forward.


Assuntos
Glucosefosfato Desidrogenase , Isoenzimas , Leucócitos/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Proteínas Sanguíneas/fisiologia , Carboxipeptidases , Glucosefosfato Desidrogenase/sangue , Humanos , Focalização Isoelétrica , Isoenzimas/sangue , Cinética , Peso Molecular , Ligação Proteica
12.
Biochim Biophys Acta ; 759(3): 236-42, 1983 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-6224515

RESUMO

A marked erythrocyte phosphofructokinase deficiency was detected in a healthy man. His enzymatic activity was only 25% that of normal controls. His father and his son had erythrocytic phosphofructokinase activities of 50-55% that of normal controls. The chromatographic separation of erythrocytic phosphofructokinase isozymes, as well as immunological studies revealed a decrease in L-type phosphofructokinase activity. The lowered erythrocytic L-type phosphofructokinase activity was not accompanied by a decreased level of L-type phosphofructokinase in proteins. The L/M subunit ratio was similar to that of normal subjects. The defect resulted from the synthesis of stable L-type mutant subunit with high electrophoretic mobility. White blood cells, which synthesize mostly the same isozyme as L-type phosphofructokinase also showed a decreased activity and a high electrophoretic mobility. In spite of this important deficiency, and of significant metabolic alterations (a slight decrease in ATP; 2,3-diphosphoglycerate; triose phosphate), hemolysis did not appear in the propositus.


Assuntos
Eritrócitos/enzimologia , Fígado/enzimologia , Mutação , Fosfofrutoquinase-1/deficiência , Complexo Antígeno-Anticorpo , Humanos , Soros Imunes , Cinética , Masculino , Pessoa de Meia-Idade , Fosfofrutoquinase-1/sangue , Fosfofrutoquinase-1/genética , Valores de Referência
13.
FEBS Lett ; 186(1): 89-92, 1985 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-4040037

RESUMO

Heparin interacts with protein kinases in various ways; the different patterns of behavior of heparin towards protein kinases contributes to the characterization of these enzymes. We studied the interactions between heparin and a new type of tyrosine kinase extracted from the normal human red cell membrane. We found that heparin inhibited kinase activity by competition with ATP. Furthermore the interaction of heparin with the red cell membrane tyrosine kinase allowed us to use heparin-agarose chromatography as a step towards tyrosine kinase purification.


Assuntos
Membrana Eritrocítica/enzimologia , Heparina/farmacologia , Proteínas Quinases/sangue , Trifosfato de Adenosina/farmacologia , Adulto , Ligação Competitiva , Cromatografia , Humanos , Inibidores de Proteínas Quinases , Proteínas Tirosina Quinases
14.
Biochimie ; 59(8-9): 673-8, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-145878

RESUMO

The reaction mechanism of erythrocyte phosphofructokinase (PFK) was investigated by the initial velocity and the product inhibition. Intersecting lines obtained with initial velocity studies are consistent with a sequential mechanism and the formation of ternary complex as an intermediate. The product inhibition studies support an ordered Bi Bi mechanism in which fructose 6 phosphate (F6P) is the first substrate binding and adenosine diphosphate (ADP) is dissociated from the enzyme before fructose-1,6-P2 (FDP).


Assuntos
Eritrócitos/enzimologia , Fosfofrutoquinase-1/sangue , Difosfato de Adenosina/farmacologia , Frutosedifosfatos/farmacologia , Humanos , Cinética
15.
Biochimie ; 58(3): 261-7, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-819039

RESUMO

The authors have purified glucose phosphate isomerase (GPI) from human leukocytes ; they used as starting material leukemic leukocytes obtained from a patient with hyper-leukocytic acute myeloid leukemia ; it was possible to obtain several milligrams of pure enzyme from a single patient. The purification procedure includes a two step precipitation by ammonium sulfate and one column chromatography on a cation exchanger with specific elution by 6 phosphogluconate, a ligand of GPI ; of the two cation exchangers tested, phosphocellulose was found to lead to a better yield than CM-Sephadex. The end product of purification had a specific activity of 855 UI/mg and gave only one band in sodium dodecyl sulphate polyacrylamide gel electrophoresis. Anti GPI monospecific rabbit serum was obtained with purified enzyme. GPI from the various blood cells of ten normal controls was studied immunologically and the ratio of the enzymatic activity to the immunological reactivity was measured ; this ratio (i.e. the molecular specific activity) was lower in granulocytes than in lymphocytes and still more depressed in platelets and hemolysate. The significance of such differences is discussed.


Assuntos
Glucose-6-Fosfato Isomerase/sangue , Leucócitos/enzimologia , Plaquetas/enzimologia , Cromatografia de Afinidade , Eritrócitos/enzimologia , Glucose-6-Fosfato Isomerase/imunologia , Glucose-6-Fosfato Isomerase/isolamento & purificação , Granulócitos/enzimologia , Humanos , Imunodifusão , Focalização Isoelétrica , Leucemia Mieloide Aguda/enzimologia
16.
Biochimie ; 63(1): 61-5, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6452173

RESUMO

The influence of Mg2+ on the reaction catalyzed by human erythrocyte phosphofructokinase has been investigated using kinetic methods. The catalytic activity of PFK is dependent upon the presence of Mg2+ which constitutes with ATP the true Mg-ATP2- substrate. Free Mg2+ has no influence on the affinity of the enzyme for Mg-ATP2- substrate. Erythrocyte PFK is more inhibited by ATP4- and uncomplexed citrate than it is by Mg-ATP2- and Mg-citrate. Free Mg2+ relieves the MgATP2- and Mg-citrate inhibition under conditions where free ATP4-is negligible. We can assume that uncomplexed Mg2+ acts as positive effector by direct binding to the enzyme. These results emphasize the role of Mg2+ in the regulation of PFK activity in the erythrocyte.


Assuntos
Eritrócitos/enzimologia , Magnésio/farmacologia , Fosfofrutoquinase-1/sangue , Trifosfato de Adenosina/farmacologia , Citratos/farmacologia , Humanos , Cinética , Ligação Proteica
17.
Biochimie ; 58(11-12): 1359-66, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-13869

RESUMO

Various factor affecting NADPH-oxidation by resting human leucocyte granules (LG) at acid pH, have been investigated. It was found that: 1) oxidation of NADPH by LG was increasingly inhibited by increased cyanide concentrations in the medium and was abolished by 4 mM cyanide. 2) with or without cyanide in the incubation medium, LG omitted, Mn++ in the presence of NADPH induced superoxide anion (O- WITH 2) production, as evidenced by oxygen consumption and H2O2 production, which were abolished (in the absence of cyanide) by cytochrome C (a potent O- with 2 scavenger). 3) Both NADPH oxidation in the presence of 2 mM cyanide (cyanide-resistant) and in its absence (cyanide-sensitive) by LG occurred only in the presence of Mn++, and both were inhibited by superoxide dismutase. 4) Cyanide-resistant NADPH oxidation by LG generated H2O2, was inhibited by H2O2 and was not modified by "active" catalase. The ratio of cyanide-resistant NADPH oxidation/O2 uptake was 1 up to 1.25 mM NADPH, and increased above this concentration. 5) Cyanide-sensitive NADPH oxidation was inhibited by catalase and increased upon addition of H2O2. The ratio of cyanide-sensitive NADPH oxidation/O2 uptake was 2. It was concluded that after initiation by O - with 2, produced independently of LG, two sequential types of LG dependent NADPH oxidations occur. First, an O - with 2-dependent protein mediated NADPH oxidation (cyanide-resistant) which generates H2O2 and O - with 2 occurs. Second, NADPH peroxidation (cyanide-sensitive) which utilizes H2O2 takes place.


Assuntos
Grânulos Citoplasmáticos/metabolismo , NADP/sangue , Neutrófilos/metabolismo , Cianetos/farmacologia , Grânulos Citoplasmáticos/efeitos dos fármacos , Humanos , Cinética , Neutrófilos/efeitos dos fármacos , Oxirredução , Espectrometria de Fluorescência
18.
Biochimie ; 57(3): 325-35, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-238666

RESUMO

Human granulocyte 6 phosphogluconate dehydrogenase has been totally purified from a single patient with chronic granulocytic leukaemia. 48 mg of protein, of specific activity 20 IU per mg of protein, have been obtained in the course of three different steps only. The overall yield was 30 p. cent and the purification was 100 folds. Purified 6 phosphogluconate dehydrogenase was homogeneous when tested in acrylamide and acrylamide SDS gel electrophoresis or in immunodiffusion. The enzyme was immunologically identical in red blood cells, blood platelets and normal leukocytes. The fixation of both substrates, NADP-+ and 6 phosphogluconate, seemed to proceed through a non ordered mechanism. NADPH was an inhibitor strictly competitive with respect to NADP-+ and non competitive with respect to 6 phosphogluconate. 2-3 Diphosphoglycerate seemed to be able to bind on both the fixation sites of NADP-+ and 6 phosphogluconate. The inhibition by ATP was competitive with 6 phosphogluconate and non competitive with NADP-+. 6 phosphogluconate dehydrogenase was inactivated by SH reagents and was partially protected against this inactivation by both substrates. Both substrates protected the enzyme against thermal inactivation. The influence of ionic strength, pH and ions have been studied, and the results have been compared to those reported by other authors for erythrocyte enzyme.


Assuntos
Granulócitos/enzimologia , Leucemia Mieloide/enzimologia , Leucócitos/enzimologia , Fosfogluconato Desidrogenase/isolamento & purificação , Trifosfato de Adenosina/farmacologia , Sítios de Ligação , Plaquetas/enzimologia , Precipitação Química , Cromatografia por Troca Iônica , Depressão Química , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Inibidores Enzimáticos , Eritrócitos/enzimologia , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Hidroximercuribenzoatos/farmacologia , Imunodifusão , Cinética , NADP/metabolismo , Concentração Osmolar , Fosfogluconato Desidrogenase/sangue , Fosfogluconato Desidrogenase/imunologia , Cloreto de Potássio/farmacologia
19.
Am J Med ; 83(6): 1075-9, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3503575

RESUMO

From 1975 to 1983, 73 patients with aggressive non-Hodgkin's lymphoma were treated with a first-generation program including Adriamycin, VM 26, cyclophosphamide, and prednisone. Thirty-nine patients were under 60 years of age, and 34 were 60 years or older. The clinical and histologic characteristics of the two groups were similar. Using either univariate or multivariate analysis, age appeared as the only prognostic factor. Patients under 60 had a median survival of 48 months, with a five-year survival rate of 47 percent and a five-year disease-free survival rate for complete-remission patients of 72 percent. Patients 60 years or older had a median survival of 18 months with a five-year survival rate of 18 percent and a five-year disease-free survival rate for complete-remission patients of 24 percent. These highly significant differences were related to a non-significantly decreased complete-remission rate and a significantly higher relapse rate in elderly patients. Since patient selection according to age could play a role in the results achieved with intensive chemotherapy programs, randomized trials comparing the various chemotherapy programs for aggressive non-Hodgkin's lymphoma are warranted.


Assuntos
Fatores Etários , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma não Hodgkin/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prognóstico , Teniposídeo/administração & dosagem
20.
Am J Surg Pathol ; 12(8): 641-7, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3400792

RESUMO

We report an aggressive primary T-immunoblastic lymphoma of the small intestine without blood involvement or associated celiac disease. Grossly, the tumor was composed of multiple disseminated ulcerated, infiltrating, or protuberant nodular lesions. Immunologic investigation showed that lymphoma cells were of peripheral (post-thymic) T-cell origin and expressed the phenotype associated with cytotoxic-suppressor subset (Leu4/CD3+, Leu9/CD7+, Leu2/CD8+, Leu11/CD16+, Leu 7/NKcells+, FcIgG+, HLA-DR+, anti-Tac/CD25+, Ki-1/CD30-, Leu1/CD5-, Leu5/CD2-, Leu3/CD4-). A particular morphologic feature of this case is the presence of numerous azurophilic granules within the lymphoma cells, identified as lysosomes by cytochemical and ultrastructural studies. In view of recent immunologic evidence that normal cytotoxic/suppressor T-cells selectively reside within the epithelium of the normal bowel and some of them contain azurophilic granules, it could be suggested that our patient's lymphoma represents a malignant counterpart of these lymphocytes. Furthermore, the aggressive character of this T malignant lymphoma (T-ML) could be related to the expression of T-cell activation markers HLA-DR and Tac/CD25 and the proliferation-associated antigen Ki-67 on a high proportion of tumor cells.


Assuntos
Neoplasias Intestinais/ultraestrutura , Linfoma não Hodgkin/ultraestrutura , Grânulos Citoplasmáticos/ultraestrutura , Humanos , Imuno-Histoquímica , Neoplasias Intestinais/enzimologia , Neoplasias Intestinais/cirurgia , Linfoma não Hodgkin/enzimologia , Linfoma não Hodgkin/cirurgia , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Invasividade Neoplásica
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