Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ERYTHROCYTES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources
PubMed1981

[Comparative study of the electrophoretic mobility of erythrocytes and erythrocyte "ghosts" isolated form rats].

Electrophoretic mobilities of rat erythrocytes and their "ghosts" are investigated. It is that the registered figures for the electrophoretic mobilities for echinocytes and discocytes are due to their specific molecular arrangements and different charge distribution topology. The reduction of the mobilities registered for the "ghosts" compared with native erythrocytes, probably, is caused by the interactions between different species of integral peripheral membrane proteins while the "ghosts" are isolated. The redistribution of the surface charge, accompanying this process, leads to unfolding of the cytoskeleton and increase of internal resistance of the suspending media. As a result a reduction of the electrophoretic mobilities for "ghost" preparations is occurred.

Animals↗
PubMed1995

Role of hemichrome binding to erythrocyte membrane in the generation of band-3 alterations in beta-thalassemia intermedia erythrocytes.

Nine splenectomized, hematologically well-compensated beta-thalassemia intermedia patients randomly chosen from a pool of 60 similar patients were studied. Membrane proteins solubilized with nondenaturing detergent C12E8 were gel filtered on Sepharose CL-6B (Pharmacia Fine Chemicals, Uppsala, Sweden). Fractions containing higher than 4,000-kD molecular-weight aggregates were isolated and analyzed. Four patients had remarkably increased amounts of membrane-bound hemichromes and Igs. In those patients, band 3 underwent oxidative modifications such as aggregation and a decrease in sulfhydryl groups. The other five patients had low amounts of membrane-bound hemichromes and less modifications of band 3. The same band-3 modifications could be reproduced by challenging normal membranes with artificially generated hemichromes or with hemolysates prepared from thalassemic erythrocytes of the high-hemichrome group. Addition of reduced glutathione to the challenged membranes did not hinder hemichrome binding, but prevented oxidative modifications of band 3 and Ig binding to high-molecular-weight band-3 aggregates. Hemichrome binding to band 3, hemichrome-mediated oxidation of band-3 cytoplasmic domains, generation of high-molecular-weight band-3 aggregates, and enhanced opsonization by anti-band-3 antibodies is a possible sequence of events leading to phagocytic removal of erythrocytes in thalassemia.

Adolescent↗
PubMedDate not supplied

[Erythrocyte membrane permeability and the sorption capacity of erythrocytes--optimal criteria of the severity of endogenous intoxication].

Sorption capacity of erythrocytes (SCE) and erythrocyte membrane permeability (EMP) have been determined along with a number of other biochemical parameters to assess the degree of intoxication in 265 critically ill patients. EMP was determined by a modified technique of V. N. Kolmakov. A high correlation between EMP, SCE and the level of biologically active substances has been established. Therefore, EMP and SCE are regarded as basic criteria reflecting the severity of endogenous intoxication and changes in these values form the basis for intoxication classification.

Adolescent↗
PubMed2000

Effects of some medical drugs on enzyme activities of carbonic anhydrase from human erythrocytes in vitro and from rat erythrocytes in vivo.

In this study, firstly, the effects of sodium ampicillin, magnesium sulfate, and sodium dipyrone on human carbonic anhydrase (HCA) (EC 4.2.1.1.) isozymes have been investigated in vitro. Human erythrocyte CA-I and CA-II isozymes were separately purified by affinity chromatography. Inhibition or activation effects of three different medical drugs on HCA isozymes were determined using the CO(2)-Hydratase method by plotting activity %vs [medical drug]. I(50)values of the drugs exhibiting inhibition effects were found by means of these graphs. It was observed on HCA-I hydratase activity that sodium ampicillin and sodium dipyrone showed inhibition and activation effects, respectively. However, magnesium sulfate showed no effect. It was observed on HCA-II hydratase activity that sodium ampicillin and magnesium sulfate showed an inhibition effect, and sodium dipyrone showed an activation effect. In addition, in vivo studies were performed for these medical drugs in Sprague-Dawley rats. It was demonstrated that CA in erythrocytes was significantly inhibited by these drugs in 3 h.

Ampicillin↗
PubMed1988

Anti-erythrocyte antibodies in ulcerative colitis: case report and discussion on the pathophysiology of anti-erythrocyte antibody.

A case of ulcerative colitis (UC) associated with anti-erythrocyte antibodies is reported. A 27-year-old male visited our department because of a relapse of UC, and his condition was diagnosed as severe and extensive colitis. He was vigorously treated with prednisolone (50 mg/day i.v.) and TPN, but no response was obtained. Subtotal colectomy with ileostomy was performed on the 22nd hospital day, and a proctosigmoidectomy was performed on him six months later. Preoperative blood type and screen disclosed that his blood was not cross-matched either on the forward or reverse typing. His ABO blood group could not be identified as "B", as determined upon admission, and his Coombs' test was positive. Further studies revealed that his Rh group was CcDEe. Anti-I antibody was detected in his serum and eluate from erythrocytes were identified as anti-E and c. Titers of the antibodies were strongest in the preoperative period and became weak following colectomy, but the antibodies did not disappear even after the large bowel was totally removed.

Adult↗
PubMed1977

Effects of erythrocyte lysate and erythrocyte-conditioned medium on erythroid cells in vitro.

A component of erythrocyte-conditioned medium has been shown to inhibit the incorporation of tritiated thymidine into erythroblasts from fetal mouse liver, proliferating in vitro. This component, however, has no detectable effect on the growth of colonies of erythroid cells stimulated to grow in viscous culture media by the hormone erythropoietin. Erythrocyte lysate and preparations of haemoglobin derived from the lysate increase the number and size of the colonies growing in vitro. Results are discussed in terms of possible control mechanisms in erythropoiesis.

Animals↗
PubMed1984

Phospholipid composition of dystrophic chicken erythrocyte plasmalemmae. II. Characterization of a unique lipid from dystrophic erythrocyte membranes as ethanolamine plasmalogen.

The phospholipid content of normal (line 412) and dystrophic (line 413) chicken erythrocyte plasmalemmae has been quantified on a developmental basis using sex matched controls. A specific minor phospholipid component, ethanolamine plasmalogen, is identified from dystrophic erythrocyte membrane preparations. To arrive at this identification, data from studies utilizing gas-liquid chromatography, thin-layer chromatography, [14C]ethanolamine incorporation, and biochemical assay for specific organic moieties were correlated. This phospholipid has the potential to alter and regulate membrane fluidity and thus membrane function. The possible presence of significant concentrations of plasmalogen in human dystrophic tissues may serve as a marker for dystrophy and thus be of clinical importance.

Animals↗
PubMed1985

Human erythrocyte spectrin dimer intrinsic viscosity: temperature dependence and implications for the molecular basis of the erythrocyte membrane free energy.

We have determined experimentally the temperature dependence of human erythrocyte spectrin dimer intrinsic viscosity at shear rates 8-12 s-1 using a Cartesian diver viscometer. We find that the intrinsic viscosity decreases from 43 +/- 3 ml/g at 4 degrees C to 34 +/- 3 ml/g when the temperature is increased to 38 degrees C. Our results show that spectrin dimers are flexible worm-like macromolecules with persistence length about 20 nm and that the mean square end-to-end distance for this worm-like macromolecules decreases when the temperature is increased. This implies that the spectrin dimer internal energy decreases when the end-to-end distance is increased and that the free energy increase associated with making the end-to-end distance longer than the equilibrium value for the free molecules is of entropic origin. The temperature dependence of the erythrocyte membrane shear modulus reported previously in the literature therefore appears mainly to be due to temperature dependent alterations in the membrane skeleton topology.

Erythrocyte Membrane↗
PubMed1987

Fibrinogen-induced erythrocyte aggregation: erythrocyte-binding site in the fibrinogen molecule.

The effect of fibrinogen and fibrinogen-derived products on the velocity of rouleau formation of human erythrocytes was quantitatively examined with a rheoscope combined with a video-camera, an image analyzer and a computer. (i) The velocity of rouleau formation by naturally occurring low-molecular-weight fibrinogen of 305 kDa and by desialylated fibrinogen was the same as that by native fibrinogen of 340 kDa. (ii) Concerning fibrinogen degradation products by plasmin, the velocity of rouleau formation decreased upon going from fibrinogen greater than fragment X greater than fragment Y (the ratio of molar concentration of fibrinogen, fragment X and fragment Y for giving a certain velocity of rouleau formation was approx. 1:2:5). The effect of fragments X and Y on the fibrinogen-induced rouleau formation was additive. (iii) Fragments D and E could not induce rouleau formation and did not affect the fibrinogen-, fragment X- and fragment Y-induced rouleau formation. (iv) Fibrinopeptides A and B and artificial tetrapeptides (Gly-Pro-Arg-Pro and Gly-His-Arg-Pro) did not affect the fibrinogen-induced rouleau formation. (v) The possible erythrocyte-binding site in fibrinogen molecule for leading to rouleaux was proposed to be in A alpha-chain (probably, around residues No. 207-303) near the terminal domain of the trinodular structure of fibrinogen.

Binding Sites↗
PubMed1986

Mouse monoclonal antibodies against bromelain-treated mouse erythrocytes: reactivity with erythrocytes of various species of animals and idiotypes.

Spleen and peritoneal cells from unimmunized BALB/c mice were cultured in the presence of LPS for 24 hr and fused to produce hybridomas secreting antibodies against bromelain-treated mouse erythrocytes (BrMRBC). Three clones from spleen cells and eight clones from peritoneal cells were isolated and characterized further. All the monoclonal antibodies had IgMK isotype. Their reactivities against untreated and bromelain-treated erythrocytes from various species were assessed by hemolysis and indirect radioimmunoassay; all the clones had similar antigen specificities. On the isoelectric focussing patterns of light chains, they were separated into two groups, two and nine clones, and all the light chains in each group showed identical patterns. The two groups shared no common idiotope detectable by anti-idiotype antibodies prepared by immunization of rabbits with the monoclonal antibodies, but all the antibodies in each group shared common idiotopes. In each group, one antibody had a unique idiotope different from any other antibody, but eight antibodies in a group shared another identical idiotope. These findings suggest the restricted heterogeneity of anti-BrMRBC antibodies in the mouse.

Animals↗
PubMed1976

The relationship between erythrocyte superoxide dismutase activity and erythrocyte copper levels in normal subjects and in patients with rheumatoid arthritis.

A quantitative assay for erythrocyte superoxide dismutase activity using the xanthine-xanthine oxidase-nitro blue tetrazolium system which is applicable to clinical material is described. The in-batch precision of the method is 3.5% and the between-batch precision is 8.8%. Employing this assay, erthrocyte superoxide dismutase activities were measured in 50 normal subjects and in 50 patients with rheumatoid arthritis. There was no significant correlatiion between superoxide dismutase activity and erthrocyte copper concentration. Erythrocyte copper was lower in female rheumatoid patients than in normals. This difference was not accompanied by a difference in superoxide dismutase activity.

Adult↗
PubMed1975

Increased affinity of guinea pig thymocytes and thymus-dependent lymphocytes for papain-treated rabbit erythrocytes compared to untreated erythrocytes.

The affinity of guinea pig thymocytes and peripheral T lymphocytes for rabbit erythrocytes was found to be enhanced following treatment of the erythrocytes with papain. By increasing the numbers of rosette-forming cells and giving stronger, more stable rosettes, this procedure increases the usefulness of the reaction as a T cell marker in guinea pigs.

Animals↗
PubMed1975

The hemoglobins of the developing chicken embryos. Fractionation and globin composition of the individual component of total erythrocytes and of a single erythrocyte type.

The hemoglobins of the chicken embryo at several stages of development have been isolated in pure form by column chromatography and their relative amounts and globin compositions determined. The analyses on separated primitive and definitive erythrocytes show that the first contain four hemoglobins different from the adult ones. The two major ones at four days, decrease gradually and are no longer detectable from 15 days on. The two minor ones increase up to 6-7 days, then decrease but are still present at hatching. The definitive embryonic erythrocytes contain two hemoglobins identical to the adult ones but their ratios change gradually during development and approach that of the adult hemoglobins at hatching.

Animals↗
PubMed1988

Studies on the energy metabolism of opossum Didelphis virginiana erythrocytes--III. Metabolic depletion with 2-deoxyglucose markedly accelerates methemoglobin reduction in opossum but not in human erythrocytes.

1. Glucose-depleted, nitrite-treated erythrocytes reduce ferriheme in vitro in an environment 100 mM to 2-deoxy-D-glucose at a rate of 2.4 microM/ml cells/hr (opossum) and 0.37 microM/ml cells/hr (human). 2. During the process of methemoglobin reduction the breakdown of adenine ribonucleotides is more rapid in opossum (0.9 microM/g hg/hr) than in human (0.36 microM/g hg/hr) erythrocytes. 3. Radiolabelled ribose from [U-14C] ATP is catabolized exclusively to [14C] lactate in opossum, and to [14C] pyruvate and [14C] lactate in human red cells.

Adenosine Triphosphate↗
PubMed2005

Characterization of prolidase activity in erythrocytes from a patient with prolidase deficiency: comparison with prolidase I and II purified from normal human erythrocytes.

OBJECTIVES: The purpose of this study was to investigate the effect of various amino acids and their metabolites on the activities of prolidase I and II from human erythrocytes compared to those in a patient with prolidase deficiency. DESIGN AND METHODS: Prolidase I and II from human erythrocytes were purified by using column chromatography. Prolidase activity against various iminodipeptides was determined by spectrophotometry using Chinard's method. RESULTS: The activities of prolidase I and II against glycylproline and methionylproline were enhanced by glycine, L- and D-isoforms of alanine and serine and D-isoforms of valine, leucine and isoleucine. L-isoforms of branched amino acids inhibited the activity of prolidase I. On the other hand, the activity of prolidase II was enhanced by all of these L-branched amino acids. The patient's prolidase activity was also enhanced by all the L- and D-branched amino acids. CONCLUSION: The activities of prolidase I and II against various iminodipeptides were prominently enhanced by glycine, but the effect of L-valine differed between the two enzymes. Enzymatic properties of the patient's prolidase were essentially the same as those of prolidase II.

Amino Acids↗
PubMed2001

Effects of metamizol and magnesium sulfate on enzyme activity of glucose 6-phosphate dehydrogenase from human erythrocyte in vitro and rat erythrocyte in vivo.

OBJECTIVE: Effects of metamizol and magnesium sulfate on erythrocyte glucose 6-phosphate dehydrogenase enzyme activity were investigated in in vitro and in vivo conditions. METHODS: For in vitro studies, glucose 6-phosphate dehydrogenase was purified from human erythrocyte and rats were used for in vivo studies. Enzyme activity was determined according to the Beutler method by using a spectrophotometer at 340 nm. RESULTS: The results of in vitro study showed that their mean K(i) values were 6.35 x 10(-3) M for metamizol and 1.32 x 10(-2) M for magnesium sulfate and their inhibition types were uncompetitive. I(50) value was 17 mM for metamizol and 50 mM for magnesium sulfate in in vitro study. In the case of in vivo studies, 200 mg/kg metamizol inhibited the enzyme activity by 40% during the first 1.5 h (p < 0.05), and 225 mg/kg magnesium sulfate significantly inhibited the enzyme activity throughout 24 h (p < 0.01). CONCLUSION: The results of this study suggested that metamizol and magnesium sulfate have significant inhibition effect on the activity of glucose 6-phosphate dehydrogenase enzyme in both in vivo and in vitro.

Ammonium Sulfate↗
PubMed2002

Erythrocyte glutathione peroxidase activity, plasma malondialdehyde and erythrocyte glutathione levels in hemodialysis and CAPD patients.

OBJECTIVES: Cardiovascular disease is the major cause of mortality in patients receiving hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) due to chronic renal failure. Increased lipid peroxidation and depletion of antioxidants may contribute to increased risk of atherosclerosis. We have therefore assessed the effect of hemodialysis and CAPD on oxidant and antioxidant status. DESIGN AND METHODS: Plasma malondialdehyde (MDA), Glutathione (GSH) levels and glutathione peroxidase (Gpx) activities were determined in 20 healthy persons (control), 20 patients on HD, 16 patients on CAPD. RESULTS: MDA was elevated in posthemodialysis and CAPD patients in comparison to prehemodialysis and control groups (posthemodialysis 1.39 +/- 0.38 nmol/mL, CAPD 1.26 +/- 0.27 nmol/mL, prehemodilaysis 0.83 +/- 0.22 nmol/mL, controls 0.72 +/- 0.21 nmol/mL p < 0.0001). With respect to antioxidants, glutathione levels were significantly lower in prehemodialysis, posthemodialysis and CAPD groups than those in control group (prehemodialysis 16.82 +/- 6.73 mg/dL RBC, posthemodialysis 31.43 +/- 11.88 mg/dL RBC, CAPD 40 +/- 12.72 mg/dL RBC, controls 62.26 +/- 24.01 mg/dL RBC, p < 0.0001). While erythrocyte GSH levels were significantly lower in the prehemodialysis patients than those in posthemodialysis and CAPD patients (p < 0.0001), it was significantly lower in posthemodialysis patients than those in CAPD patients (p < 0.05). There were no significant differences with respect to erythrocyte Gpx levels among the groups (p > 0.05). CONCLUSIONS: These findings indicate oxidative stress in patients with chronic renal failure which is further exacerbated by hemodialysis and CAPD, as evidenced by increased lipid peroxidation and low antioxidant levels.

Adult↗
PubMed1984

Plasma cells and their precursors. IV. Cross-reacting and non-cross-reacting, sheep erythrocyte lysing IgG antibody clones induced in rabbits immunized with rat- and chicken-erythrocytes.

Rabbits were i.v. immunized with rat erythrocytes or chicken erythrocytes. The sera were investigated using the IEF technique. A number of the RRBC immunized animals and a high proportion of the CRBC immunized animals contained SRBC-lysing IgG antibody clones in addition to apparently normal anti-RRBC or anti-CRBC antibodies. Intravenous immunization with RRBC, followed by immunization with CRBC, yielded clones of SRBC-lysing IgG antibodies in almost every rabbit tested. By varying the interval between the RRBC- and CRBC injections, we established that the time needed for the RRBC-induced production of the responsible SRBC-specific IgG AFCP is approximately 5 days. These cells show an average functional half-life of 75 days. At least some of the RRBC- and CRBC-evoked SRBC-lysing IgG antibody clones are incapable of lysing either RRBC or CRBC. We suggest that the production of cross-reactive and non-cross-reactive, hetero-specific AFCP provides a natural explanation for the availability of preexistent AFCP responsible for the presence of the "early phase" of the IgG antibody response to several antigens.

Animals↗