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1.
J Clin Invest ; 88(1): 76-81, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2056132

RESUMO

The molecular defect responsible for the shortened beta-spectrin chain variant, spectrin Rouen, was identified by analysis of cDNA and genomic DNA of affected individuals after amplification by the polymerase chain reaction. Peripheral blood reticulocyte RNA was transcribed into cDNA and amplified using primers corresponding to the 3' end of beta-spectrin cDNA. Agarose gel electrophoresis of cDNA amplification products from affected individuals revealed the expected band of 391 bp as well as a shortened band of 341 bp. Nucleotide sequencing of the shortened cDNA amplification product revealed that the sequences corresponding to the penultimate exon of the beta-spectrin gene (exon Y) were absent. This result was confirmed by hybridization of a Southern blot of amplification products with a labeled probe specific for exon Y. Nucleotide sequencing of the proband's amplified genomic DNA corresponding to this region of the beta-spectrin gene revealed a mutation in the 5' donor consensus splice site of the intron downstream of the Y exon, TGG/GTGAGT to TGG/GTTAGT, in one allele. We postulate that this mutation leads to the splicing out or skipping of exon Y, thus producing a shortened beta-spectrin chain. To our knowledge, this is the first documented example of exon skipping as the cause of a shortened beta-spectrin chain in a case of hereditary elliptocytosis. The exon skip results in the loss of the 17 amino acids of exon Y and creates a frameshift with the synthesis of 33 novel amino acids prior to premature chain termination 14 residues upstream of the normal carboxy terminus of the beta-spectrin chain, giving a mutant beta-spectrin chain that is 31 amino acids shorter than the normal chain.


Assuntos
Eliptocitose Hereditária/genética , Éxons , Mutação , Espectrina/genética , Sequência de Aminoácidos , Sequência de Bases , DNA/análise , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
2.
J Clin Invest ; 89(3): 892-8, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1541680

RESUMO

We studied nine individuals from five unrelated families with alpha I/46-50a hereditary elliptocytosis (HE) or hereditary pyropoikilocytosis (HPP), including one of the original HHP probands first reported by Zarkowsky and colleagues (1975. Br. J. Haematol. 29:537-543). Biochemical analysis of erythrocyte membrane proteins from these patients revealed, as a common abnormality, the presence of the alpha I/46-50a peptide after limited tryptic digestion of spectrin. The polymerase chain reaction was utilized to study the structure of the DNA encoding the alpha I domain of spectrin in the affected individuals. The DNA sequence of the alpha-spectrin gene encoding the region of the alpha-spectrin chain surrounding the abnormal proteolytic cleavage site was normal. We identified a point mutation causing the replacement of a highly conserved leucine residue by proline at position 207 in the alpha-spectrin chain, a site 51 residues to the amino-terminal side of the abnormal proteolytic cleavage site. Analysis of the proposed triple helical model of spectrin repeats reveals that the mutation occurs in helix 2 at a position directly opposite the abnormal proteolytic cleavage site in helix 3, making this the first report of a mutation occurring in helix 2 of a repeat in the alpha I domain of spectrin. These results add to the molecular heterogeneity of mutations associated with HE/HPP and provide further support for the proposed triple helical model of spectrin. Disruption of this proposed alpha-helical structure by helix-breaking proline substitutions may result in a functionally defective spectrin chain.


Assuntos
Anemia Hemolítica Congênita/genética , Eliptocitose Hereditária/genética , Espectrina/química , Sequência de Aminoácidos , Sequência de Bases , Deformação Eritrocítica , Eritrócitos Anormais , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Conformação Proteica , Espectrina/análise , Espectrina/genética
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.
J Clin Invest ; 97(2): 373-80, 1996 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8567957

RESUMO

We studied a French kindred with typical hereditary spherocytosis (HS). Studies of erythrocytes and erythrocyte membranes from HS individuals revealed abnormal erythrocyte membrane mechanical stability as well as 15-20% deficiency of band 3, the anion transporter. Anion transport studies of red cells from two affected individuals revealed decreased sulfate flux. Nucleotide sequence of cDNA encoding the distal third of the cytoplasmic domain and the entire transmembrane domain of band 3 obtained by RT-PCR of reticulocyte RNA of an affected family member was normal. Sequence analysis of genomic DNA from an HS individual identified a nonsense mutation of the band 3 gene, Q330X, near the end of the band 3 cytoplasmic domain. This mutation was present in genomic DNA of all HS family members and absent in DNA of unaffected family members. Using an RT-PCR-based assay, a marked quantitative decrease in accumulation of the mutant band 3 RNA was detected. Thus the codon 330 nonsense mutation is responsible for the decreased accumulation of mutant band 3 RNA and the deficiency of band 3 protein in this kindred. These results have important implications for the role of band 3 defects in the membrane pathobiology of HS as well as for the techniques used in detection of HS mutations.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Esferocitose Hereditária/genética , Ânions/sangue , Sequência de Bases , Transporte Biológico , Primers do DNA/química , Eritrócitos/metabolismo , Feminino , Expressão Gênica , Genes Dominantes , Humanos , Masculino , Dados de Sequência Molecular , Linhagem , Mutação Puntual , RNA Mensageiro/metabolismo , Reticulócitos/metabolismo
5.
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
6.
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
7.
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
8.
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
9.
FEBS Lett ; 507(3): 241-6, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11696349

RESUMO

Two human divalent cation transporters of the ZIP family, hZip1 and hZip2, homologous to Irt1 (Arabidopsis thaliana), the first identified member, have been described. They were shown by transfection into K562 cells to be localized at the plasma membrane and to mediate zinc uptake. Here we report a differential subcellular localization of hZip1 according to cell type. By transient expressions of EGFP-hZip1, FLAG-tagged or native hZip1, we observed that hZip1 has a vesicular localization in COS-7 cells or in several epithelial cell lines, corresponding partially to the endoplasmic reticulum. Using anti-hZip1 antibodies, we confirmed the intracellular localization of the endogenous protein in PC-3, a prostate cancer cell line.


Assuntos
Proteínas de Transporte/metabolismo , Vesículas Citoplasmáticas/metabolismo , Animais , Sequência de Bases , Células COS , Proteínas de Transporte/genética , Adesão Celular , Citoplasma/metabolismo , Proteínas de Fluorescência Verde , Humanos , Membranas Intracelulares/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Dados de Sequência Molecular , Neoplasias da Próstata/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Tumorais Cultivadas
10.
Biochimie ; 58(11-12): 1311-20, 1976.
Artigo em Francês | MEDLINE | ID: mdl-1016652

RESUMO

Pure rabbit fibrinogen was prepared by a method involving two ammonium sulfate precipitations, one 2 M phosphate buffer precipitation, one DEAE cellulose chromatography and lastly one Sepharose 6 B chromatography. The aminoacid composition was determined and an immunonephelemetric assay was proposed. This assay followed an accurate determination of fibrinogen concentration in a rabbit with inflammatory reaction.


Assuntos
Fibrinogênio , Aminoácidos/análise , Animais , Cromatografia DEAE-Celulose , Cromatografia em Gel , Fibrinogênio/isolamento & purificação , Imunoeletroforese , Masculino , Coelhos
11.
Leuk Res ; 18(11): 837-42, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7967710

RESUMO

We have previously shown that heparin and heparan sulfate stimulate the growth of human erythroleukemia cells in vitro in the presence of serum or plasma. To determine whether heparin and other glycosaminoglycans (GAGs) are involved in the growth of leukemia cells, effects of GAGs on the growth of three leukemia cell lines expressing different phenotypes, the HEL, HL60 and U937 cell lines were studied using both plasma clot and serum-free agar systems. The cells were cultured with different doses of six GAGs: hyaluronic acid, chondroitin sulfate, dermatan sulfate, keratan sulfate, heparin and heparan sulfate. It was found that, in serum-free agar system, no GAG was able to stimulate (HEL) cell growth. In contrast, when serum-containing culture systems were used, all six GAGs promoted colony formation of HL60 and U937 cells. In addition, all GAGs, except keratan sulfate, stimulated the growth of HEL cells. The findings suggest that the GAGs may play an indirect role in enhancing leukemia cell proliferation by different mechanisms.


Assuntos
Glicosaminoglicanos/farmacologia , Leucemia/patologia , Divisão Celular/efeitos dos fármacos , Condroitina/farmacologia , Meios de Cultura , Dermatan Sulfato/farmacologia , Heparina/farmacologia , Heparitina Sulfato/farmacologia , Humanos , Ácido Hialurônico/farmacologia , Sulfato de Queratano/farmacologia , Leucemia Monocítica Aguda/patologia , Leucemia Promielocítica Aguda/patologia , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
12.
Am J Clin Pathol ; 108(4): 391-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9322591

RESUMO

Marked variations are seen in the clinical manifestations of hereditary elliptocytosis (HE). To define the cellular alteration(s) that best reflect the variable expression of the disease, we evaluated the pathobiologic features of red blood cells in a series of 18 patients with HE, 15 persons from six families with HE as a result of defects in spectrin, and 3 persons from one family with HE caused by partial or total deficiency of protein 4.1. We found that decreased cellular deformability is a distinguishing feature of red blood cells in all patients studied. Comparison of volume and hemoglobin content histograms of red blood cells and reticulocytes revealed that cell fragmentation is a feature of mature red blood cells. The extent of red blood cell fragmentation as reflected by increased percentage of microcytic red blood cells was the best indicator of the severity of hemolytic anemia. Furthermore, we found that the observed variations in cellular properties of HE red blood cells in different persons is the consequence of varying amounts of mutant protein assembled into the membrane. These findings enabled us to define the mechanistic basis for cellular changes in this red blood cell membrane disorder better and also to obtain insight into the cellular basis for variable clinical expression.


Assuntos
Eliptocitose Hereditária/patologia , Eritrócitos/patologia , Eliptocitose Hereditária/sangue , Eliptocitose Hereditária/genética , Deformação Eritrocítica , Feminino , Hemoglobinas/análise , Humanos , Masculino , Mutação , Contagem de Reticulócitos , Índice de Gravidade de Doença , Espectrina/genética
13.
Cancer Genet Cytogenet ; 97(2): 155-6, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9283599

RESUMO

Trisomy 14 in hematologic disease is a rare finding and is almost exclusively associated with myeloid cell lineage. We present a case of refractory anemia (MDS-RA) with the uncommon features of marked elliptocytosis and schistocytosis in the peripheral blood and isochromosome 14q. The analysis of the clinical outcome of this case and of others of myelodysplastic (MDS)/myeloproliferative syndromes with trisomy 14 as the sole abnormality suggests that it does not confer an unfavorable prognosis.


Assuntos
Anemia Refratária/genética , Aberrações Cromossômicas/genética , Cromossomos Humanos Par 14 , Idoso , Anemia Refratária/patologia , Bandeamento Cromossômico , Transtornos Cromossômicos , Humanos , Cariotipagem
14.
Trans R Soc Trop Med Hyg ; 96(2): 143-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12055801

RESUMO

In the Madagascar Highlands, 0.76% of children from 168 random primary schools, and 19 of 150 families from 3 villages, had oval-shaped erythrocytes. Most harboured the deletion in the band 3 gene characteristic of South-East Asian ovalocytosis. This genetic trait supports the Indonesian origin of the Madagascar settlement.


Assuntos
Eliptocitose Hereditária/epidemiologia , Adulto , Altitude , Criança , Estudos Transversais , Eliptocitose Hereditária/genética , Emigração e Imigração , Deleção de Genes , Humanos , Madagáscar/epidemiologia , Mutação/genética , Reação em Cadeia da Polimerase/métodos , Prevalência
15.
J Biochem Biophys Methods ; 21(4): 299-309, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2089072

RESUMO

Readily available elements were used to build an automatic apparatus dedicated to the preparation of erythrocyte ghosts. The apparatus is designed around a low-cost re-usable hollow-fiber filtration cartridge (marketed for therapeutic plasmapheresis). The apparatus is controlled by a simple programmer (based on a diode matrix and low cost timers and liquid level sensors): once the apparatus is loaded with whole red blood cells, washing of cells, as well as hemolysis and washing of ghosts, is performed by the machine in about 4.5 h without any operator intervention. Automatic filter cleaning takes a further 110 min.


Assuntos
Fracionamento Celular/instrumentação , Membrana Eritrocítica , Plasmaferese/instrumentação , Automação/economia , Filtração/instrumentação , Humanos
16.
J Biochem Biophys Methods ; 18(3): 227-35, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2732421

RESUMO

DNA amplification by the polymerase chain reaction (PCR) is a method capable of producing a selective and very high enrichment of a specific DNA sequence. Hence it seems to be useful in various fields from basic research to clinical applications. In order to automatize PCR we assembled for a very low cost a mechanical system designed to carry a test tube holder successively in three thermal baths set at the required temperatures for the reaction. Two examples of the use of this machine are given: (i) amplification of DNA of a particular subtype of acute intermittent porphyria; (ii) the detection of the chimeric c-abl/bcr message found in chronic myelogenous leukemia cells.


Assuntos
DNA/genética , Técnicas de Amplificação de Ácido Nucleico , Sequência de Bases , DNA Polimerase Dirigida por DNA , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Dados de Sequência Molecular , Porfirias/genética , Proto-Oncogenes , RNA Mensageiro/genética
17.
Gastroenterol Clin Biol ; 8(5): 407-13, 1984 May.
Artigo em Francês | MEDLINE | ID: mdl-6735052

RESUMO

We report the results of a diagnosis and treatment scheme used in 35 patients with primary gastrointestinal lymphoma studied between 1972 and 1982. There were 17 lymphomas of the stomach, 13 of the small bowel, 6 of the colon and/or the rectum. According to the Kiel classification and/or the International Working Formulation, 10 were "good risk" lymphomas, 25 were "bad risk" lymphomas. According to the Musshoff modified Ann Arbor staging classification, 16 were localized lymphomas (stage IE and II1E), 19 were disseminated lymphomas (stages II2E, IIIE or IV). The treatment scheme included laparotomy for staging and resection, total abdominal irradiation (until 1977), and polychemotherapy with or without adriamycin depending on histologic grade. The median survival was greater than the median follow-up with a survival plateau at 0.53 after 47 months. Amongst the prognostic factors studied, the digestive initial localization had no prognostic significance; on the other hand, survival depended on abdominal extension, histologic grade according to the classifications used for lymph-nodes lymphomas, and resection possibilities, and especially on achievement of complete remission. These good results emphasize the importance of combining surgical resection with chemotherapy and early assessment of the treatment in order to rapidly obtain complete remission, the way of achieving prolonged survival.


Assuntos
Neoplasias Gastrointestinais/terapia , Linfoma/terapia , Adulto , Idoso , Terapia Combinada/mortalidade , Feminino , França , Neoplasias Gastrointestinais/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade
18.
Ann Biol Clin (Paris) ; 45(2): 224-8, 1987.
Artigo em Francês | MEDLINE | ID: mdl-3619146

RESUMO

Erythrocyte adhesion to endothelium was measured using human endothelial cells in culture and a radiometric technique. Erythrocyte adhesion was found to be significantly increased in diabetes mellitus and sickle cell anemia. In both diseases the extent of adhesion was correlated with the clinical severity of the disease. Using 3H Leucine radio-labelled reticulocytes or red cells separated by density gradient according to their age it was possible to further investigate the red cell abnormality responsible for increased adhesion. A population of abnormal reticulocytes in sickle cell anemia exhibited a higher adhesion than the whole red cell population. Diabetic dense red cells (old red cells) appeared to be mostly responsible for the increase in erythrocyte adhesion to endothelium observed in diabetes mellitus.


Assuntos
Anemia Falciforme/sangue , Diabetes Mellitus Tipo 1/sangue , Eritrócitos/fisiologia , Traço Falciforme/sangue , Adulto , Adesão Celular , Células Cultivadas , Endotélio/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reticulócitos/fisiologia
19.
Medicina (B Aires) ; 52(2): 109-15, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1308902

RESUMO

Using clinical, functional and biochemical criteria, we studied the red blood cell membrane of nine caucasic patients from four families with hereditary elliptocytosis (HE). From a clinical point of view, seven cases were classified as compensated mild HE in whom anemia and splenomegaly are absent and reticulocytosis is slightly elevated or normal. Two cases were uncompensated mild HE with anemia, reticulocytosis, splenomegaly and erythrocytic fragmentation. (Table 1). Three individuals from one family displayed a significant reduction of protein 4.1 by polyacrylamide gel electrophoresis; one of them was uncompensated HE. The patterns of limited tryptic digestion and dimer/tetramer proportion of spectrin were normal. The study of red cell deformability by ectacytometry revealed that the cell deformability under isotonic conditions was decreased in all HE patients and the curve obtained had trapezoidal shape (Fig. 3). We found that the deformability index correlated well with the degree of anemia, but no correlation was observed between clinical findings, morphological phenotype and specific molecular etiology. According to our knowledge, this is the first report on molecular and functional studies in HE in Argentina.


Assuntos
Proteínas do Citoesqueleto , Eliptocitose Hereditária/sangue , Deformação Eritrocítica , Proteínas de Membrana/deficiência , Neuropeptídeos , Adulto , Idoso , Criança , Pré-Escolar , Eletroforese em Gel de Poliacrilamida , Membrana Eritrocítica/metabolismo , Família , Feminino , Citometria de Fluxo , Humanos , Masculino , Espectrina/biossíntese
20.
Presse Med ; 12(43): 2751-3, 1983 Nov 26.
Artigo em Francês | MEDLINE | ID: mdl-6228836

RESUMO

Hereditary pyropoikilocytosis is a congenital haemolytic anaemia recently described. A new case is reported in which the condition was diagnosed by a study of erythrocyte membrane proteins in the parents. The unusual clinical features of this case lead to a discussion of the relationship between hereditary pyropoikilocytosis and other rare forms of elliptocytosis in children.


Assuntos
Anemia Hemolítica Congênita/sangue , Eritrócitos Anormais/patologia , Hemólise , Eritrócitos Anormais/análise , Temperatura Alta , Humanos , Recém-Nascido , Masculino , Espectrina/análise
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