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Sample records for influence erythrocyte phenotypes

  1. A novel laboratory technique demonstrating the influences of RHD zygosity and the RhCcEe phenotype on erythrocyte D antigen expression

    PubMed Central

    McGann, Patrick T.; Despotovic, Jenny M.; Howard, Thad A.; Ware, Russell E.

    2015-01-01

    D antigen is the most immunogenic and clinically relevant antigen within the complex Rh blood group system. Variability of D antigen expression was first described decades ago but has rarely been investigated quantitatively, particularly in the context of RHD zygosity along with RhCcEe serological phenotype. With IRB approval, 107 deidentified blood samples were analyzed. Rh phenotypes were determined serologically by saline technique using monoclonal antibodies against D, C, c, E, and e antigens. RHD zygosity was determined using both PCR-restriction fragment length polymorphisms and quantitative real-time PCR techniques. A novel and robust method was developed for quantitation of erythrocyte D antigen sites using calibrated microspheres and flow cytometry, allowing correlation of D antigen density with RHD zygosity and expression of Rh CcEe antigens. Subjects homozygous for RHD expressed nearly twice the number of D antigen sites compared with RHD hemizygotes (33,560 ± 8,222 for DD versus 17,720 ± 4,471 for Dd, P < 0.0001). Expression of c or E antigens was associated with significantly increased erythrocyte D antigen expression, whereas presence of C or e antigens reduced expression. These data and this novel quantitation method will be important for future studies investigating the clinical relevance of D antigen variability. PMID:22121029

  2. Blood viscosity: influence of erythrocyte deformation.

    PubMed

    Chien, S; Usami, S; Dellenback, R J; Gregersen, M I

    1967-08-18

    Suspensions of canine and human erythocytes hardened with acetaldehyde differ from the suspensions of normal erythrocytes with respect to their rheological behavior. Normal erythrocytes can be packed by centrifugation so that the sediment volume is nearly 100 percent cells, but the hardened erythrocytes (RBC's) can be packed only to approximately 60 percent cells. At the same cell percentage the viscosity of the hardened RBC suspension is higher than that of the suspension of normal erythocytes. An increase in shear stress deforms the normal erythocytes and lowers the suspension viscosity, but has no influence on the viscosity of the hardened cell suspension. In blood with high cell percentages, the shear deformation of normal RBC's plays an important role in reducing viscosity and facilitating flow at high shear stresses. PMID:17842793

  3. Phenotypic variation of erythrocyte linker histone H1.c in a pheasant (Phasianus colchicus L.) population.

    PubMed

    Kowalski, Andrzej; Pa Yga, Jan; Górnicka-Michalska, Ewa; Bernacki, Zenon; Adamski, Marek

    2010-07-01

    Our goal was to characterize a phenotypic variation of the pheasant erythrocyte linker histone subtype H1.c. By using two-dimensional polyacrylamide gel electrophoresis three histone H1.c phenotypes were identified. The differently migrating allelic variants H1.c1 and H1.c2 formed either two homozygous phenotypes, c1 and c2, or a single heterozygous phenotype, c1c2. In the pheasant population screened, birds with phenotype c2 were the most common (frequency 0.761) while individuals with phenotype c1 were rare (frequency 0.043).

  4. Blood viscosity: influence of erythrocyte aggregation.

    PubMed

    Chien, S; Usami, S; Dellenback, R J; Gregersen, M I; Nanninga, L B; Guest, M M

    1967-08-18

    The addition of purified canine or bovine fibrinogen to suspensions of canine erythocytes in Ringer solution caused an increase in viscosity and the formation of aggregates of erythocytes. Both of these effects became increasingly pronounced as the fibrinogen concentration was raised, and they approached plateaus with 1 gram of fibrinogen per 100 milliliters. An increase in shear rate (or shear stress) reduced both the effect on viscosity and the aggregate size. The data suggest that fibrinogen causes an increase in blood viscosity and a departure from Newtonian behavior by interacting with erythrocytes to form cell aggregates which can be dispersed by shear stress. PMID:17842794

  5. Platelet-mediated clumping of Plasmodium falciparum-infected erythrocytes is a common adhesive phenotype and is associated with severe malaria

    PubMed Central

    Pain, Arnab; Ferguson, David J. P.; Kai, Oscar; Urban, Britta C.; Lowe, Brett; Marsh, Kevin; Roberts, David J.

    2001-01-01

    Sequestration of malaria-infected erythrocytes in the peripheral circulation has been associated with the virulence of Plasmodium falciparum. Defining the adhesive phenotypes of infected erythrocytes may therefore help us to understand how severe disease is caused and how to prevent or treat it. We have previously shown that malaria-infected erythrocytes may form apparent autoagglutinates of infected erythrocytes. Here we show that such autoagglutination of a laboratory line of P. falciparum is mediated by platelets and that the formation of clumps of infected erythrocytes and platelets requires expression of the platelet surface glycoprotein CD36. Platelet-dependent clumping is a distinct adhesive phenotype, expressed by some but not all CD36-binding parasite lines, and is common in field isolates of P. falciparum. Finally, we have established that platelet-mediated clumping is strongly associated with severe malaria. Precise definition of the molecular basis of this intriguing adhesive phenotype may help to elucidate the complex pathophysiology of malaria. PMID:11172032

  6. Expedited CO2 respiration in people with Miltenberger erythrocyte phenotype GP.Mur.

    PubMed

    Hsu, Kate; Kuo, Mei-Shin; Yao, Ching-Che; Lee, Ting-Ying; Chen, Yi-Chun; Cheng, Han-Chih; Lin, Chia-Hao; Yu, Tzung-Han; Lin, Hui-Ju

    2015-05-22

    In Southeast Asia, Miltenberger antigen subtype III (Mi.III; GP.Mur) is considered one of the most important red blood cell antigens in the field of transfusion medicine. Mi.III functions to promote erythrocyte band 3 expression and band 3-related HCO3(-) transport, with implications in blood CO2 metabolism. Could Mi.III affect physiologic CO2 respiration in its carriers? Here, we conducted a human trial to study the impacts of Mi.III expression in respiration. We recruited 188 healthy, adult subjects for blood typing, band 3 measurements, and respiratory tests before and after exercise. The 3-minute step exercise test forced the demand for CO2 dissipation to rise. We found that immediately following exercise, Mi.III + subjects exhaled CO2 at greater rates than Miltenberger-negative subjects. Respiration rates were also higher for Mi.III + subjects immediately after exercise. Blood gas tests further revealed distinct blood CO2 responses post-exercise between Mi.III and non-Mi.III. In contrast, from measurements of heart rates, blood O2 saturation and lactate, Mi.III phenotype was found to be independent of one's aerobic and anaerobic capacities. Thus, Mi.III expression supported physiologic CO2 respiration. Conceivably, Mi.III + people may have advantages in performing physically enduring activities.

  7. Expedited CO2 respiration in people with Miltenberger erythrocyte phenotype GP.Mur.

    PubMed

    Hsu, Kate; Kuo, Mei-Shin; Yao, Ching-Che; Lee, Ting-Ying; Chen, Yi-Chun; Cheng, Han-Chih; Lin, Chia-Hao; Yu, Tzung-Han; Lin, Hui-Ju

    2015-01-01

    In Southeast Asia, Miltenberger antigen subtype III (Mi.III; GP.Mur) is considered one of the most important red blood cell antigens in the field of transfusion medicine. Mi.III functions to promote erythrocyte band 3 expression and band 3-related HCO3(-) transport, with implications in blood CO2 metabolism. Could Mi.III affect physiologic CO2 respiration in its carriers? Here, we conducted a human trial to study the impacts of Mi.III expression in respiration. We recruited 188 healthy, adult subjects for blood typing, band 3 measurements, and respiratory tests before and after exercise. The 3-minute step exercise test forced the demand for CO2 dissipation to rise. We found that immediately following exercise, Mi.III + subjects exhaled CO2 at greater rates than Miltenberger-negative subjects. Respiration rates were also higher for Mi.III + subjects immediately after exercise. Blood gas tests further revealed distinct blood CO2 responses post-exercise between Mi.III and non-Mi.III. In contrast, from measurements of heart rates, blood O2 saturation and lactate, Mi.III phenotype was found to be independent of one's aerobic and anaerobic capacities. Thus, Mi.III expression supported physiologic CO2 respiration. Conceivably, Mi.III + people may have advantages in performing physically enduring activities. PMID:26000803

  8. Influence of glucose solution on the erythrocyte scattering properties

    NASA Astrophysics Data System (ADS)

    Naumenko, Elena K.

    2007-02-01

    The scattering characteristics of erythrocytes (the coefficients of extinction, scattering, absorption and indicatrixes) were calculated with using the theory Mie for spherical homogeneous spherical particles and the theory for two-layered spherical concentric particles. Transmission spectrums were measured with the spectrophotometer Cary500 in the wavelength range 460-860 n m. Specimens of liquid for imbedding of erythrocytes were preparing by mixing blood plasma a nd 50-% glucose solution with the different concentrations. The volume concentrations (hematocrit) of red blood cells (RBC) were maintained to have the same values in all specimens by adding equal volume of whole blood to immersion liquid of equal volumes. It has been shown that, contrary to theretical prediction, transmission is decreasing for all wavelengths with the addition of glucose solution in interval glucose volume concentrations 0.05 - 0.35-0.4. The subsequent increase of the glucose concentration leads to increasing of spectral transmission as a result of erythrocyte hemolysis.

  9. Variation in Plasmodium falciparum Erythrocyte Invasion Phenotypes and Merozoite Ligand Gene Expression across Different Populations in Areas of Malaria Endemicity

    PubMed Central

    Bowyer, Paul W.; Stewart, Lindsay B.; Aspeling-Jones, Harvey; Mensah-Brown, Henrietta E.; Ahouidi, Ambroise D.; Amambua-Ngwa, Alfred; Awandare, Gordon A.

    2015-01-01

    Plasmodium falciparum merozoites use diverse alternative erythrocyte receptors for invasion and variably express cognate ligands encoded by the erythrocyte binding antigen (eba) and reticulocyte binding-like homologue (Rh) gene families. Previous analyses conducted on parasites from single populations in areas of endemicity revealed a wide spectrum of invasion phenotypes and expression profiles, although comparisons across studies have been limited by the use of different protocols. For direct comparisons within and among populations, clinical isolates from three different West African sites of endemicity (in Ghana, Guinea, and Senegal) were cryopreserved and cultured ex vivo after thawing in a single laboratory to assay invasion of target erythrocytes pretreated with enzymes affecting receptor subsets. Complete invasion assay data from 67 isolates showed no differences among the populations in the broad range of phenotypes measured by neuraminidase treatment (overall mean, 40.6% inhibition) or trypsin treatment (overall mean, 83.3% inhibition). The effects of chymotrypsin treatment (overall mean, 79.2% inhibition) showed heterogeneity across populations (Kruskall-Wallis P = 0.023), although the full phenotypic range was seen in each. Schizont-stage transcript data for a panel of 8 invasion ligand genes (eba175, eba140, eba181, Rh1, Rh2a, Rh2b, Rh4, and Rh5) were obtained for 37 isolates, showing similar ranges of variation in each population except that eba175 levels tended to be higher in parasites from Ghana than in those from Senegal (whereas levels of eba181 and Rh2b were lower in parasites from Ghana). The broad diversity in invasion phenotypes and gene expression seen within each local population, with minimal differences among them, is consistent with a hypothesis of immune selection maintaining parasite variation. PMID:25870227

  10. Variation in Plasmodium falciparum erythrocyte invasion phenotypes and merozoite ligand gene expression across different populations in areas of malaria endemicity.

    PubMed

    Bowyer, Paul W; Stewart, Lindsay B; Aspeling-Jones, Harvey; Mensah-Brown, Henrietta E; Ahouidi, Ambroise D; Amambua-Ngwa, Alfred; Awandare, Gordon A; Conway, David J

    2015-06-01

    Plasmodium falciparum merozoites use diverse alternative erythrocyte receptors for invasion and variably express cognate ligands encoded by the erythrocyte binding antigen (eba) and reticulocyte binding-like homologue (Rh) gene families. Previous analyses conducted on parasites from single populations in areas of endemicity revealed a wide spectrum of invasion phenotypes and expression profiles, although comparisons across studies have been limited by the use of different protocols. For direct comparisons within and among populations, clinical isolates from three different West African sites of endemicity (in Ghana, Guinea, and Senegal) were cryopreserved and cultured ex vivo after thawing in a single laboratory to assay invasion of target erythrocytes pretreated with enzymes affecting receptor subsets. Complete invasion assay data from 67 isolates showed no differences among the populations in the broad range of phenotypes measured by neuraminidase treatment (overall mean, 40.6% inhibition) or trypsin treatment (overall mean, 83.3% inhibition). The effects of chymotrypsin treatment (overall mean, 79.2% inhibition) showed heterogeneity across populations (Kruskall-Wallis P = 0.023), although the full phenotypic range was seen in each. Schizont-stage transcript data for a panel of 8 invasion ligand genes (eba175, eba140, eba181, Rh1, Rh2a, Rh2b, Rh4, and Rh5) were obtained for 37 isolates, showing similar ranges of variation in each population except that eba175 levels tended to be higher in parasites from Ghana than in those from Senegal (whereas levels of eba181 and Rh2b were lower in parasites from Ghana). The broad diversity in invasion phenotypes and gene expression seen within each local population, with minimal differences among them, is consistent with a hypothesis of immune selection maintaining parasite variation.

  11. Distribution of sialic acid between sialoglycoproteins and other membrane components of different erythrocyte phenotypes.

    PubMed

    Udoh, A E

    1991-01-01

    The sialic acid content of erythrocytes of three different AB0 blood groups have been studied. The sialic acid contents of erythrocyte membranes containing 300 mg protein were determined and compared. Groups 0 (Rhesus negative), AB (both Rhesus negative and positive), and B (Rhesus negative) blood differed significantly (p less than 0.05) in total sialic acid content and in the distribution of sialic acid between sialoglycoproteins and other membrane components. Membrane materials containing 300 mg total protein showed sialic acid contents of 52.73 +/- 2.2 mumol sialic acid for group 0 (Rhesus negative) 34.77 +/- 1.16 mumol for group AB (Rh negative), 32.88 +/- 1.52 mumol for AB (Rh positive) and 21.23 +/- 0.84 mumol for B (Rh negative). In group 0 (Rh. neg.) membranes 39.4 +/- 1.4% of the total sialic acid was associated with the sialoglycoproteins. The percentage of sialic acids associated with sialoglycoproteins in other erythrocyte membranes were 77.7 +/- 1.3% for group B, and 55.6 +/- 1.0% and 56.4 +/- 1.8% for group AB (Rh. negative) and (Rh. positive) respectively. The changes appear to be independent of the Rhesus grouping but dependent on the AB0 grouping since membranes of the two Rhesus types of group AB had identical total sialic acid and sialoglycoproteins sialic acids. The sialic acid densities in sialoglycoproteins also differed from one erythrocyte type to another. Group 0 (Rh. negative) membrane sialoglycoproteins had sialic acid density of 140.5 +/- 3.1 nmol/mg compared to 71.7 +/- 1.2 nmol/mg for group B and 128.1 +/- 2.2 and 124.5 +/- 4.0 nmol/mg for group AB Rhesus negative and Rhesus positive respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Influence of MLS laser radiation on erythrocyte membrane fluidity and secondary structure of human serum albumin.

    PubMed

    Pasternak, Kamila; Nowacka, Olga; Wróbel, Dominika; Pieszyński, Ireneusz; Bryszewska, Maria; Kujawa, Jolanta

    2014-03-01

    The biostimulating activity of low level laser radiation of various wavelengths and energy doses is widely documented in the literature, but the mechanisms of the intracellular reactions involved are not precisely known. The aim of this paper is to evaluate the influence of low level laser radiation from an multiwave locked system (MLS) of two wavelengths (wavelength = 808 nm in continuous emission and 905 nm in pulsed emission) on the human erythrocyte membrane and on the secondary structure of human serum albumin (HSA). Human erythrocytes membranes and HSA were irradiated with laser light of low intensity with surface energy density ranging from 0.46 to 4.9 J cm(-2) and surface energy power density 195 mW cm(-2) (1,000 Hz) and 230 mW cm(-2) (2,000 Hz). Structural and functional changes in the erythrocyte membrane were characterized by its fluidity, while changes in the protein were monitored by its secondary structure. Dose-dependent changes in erythrocyte membrane fluidity were induced by near-infrared laser radiation. Slight changes in the secondary structure of HSA were also noted. MLS laser radiation influences the structure and function of the human erythrocyte membrane resulting in a change in fluidity.

  13. α-Thalassemia does not seem to influence erythrocyte deformability in sickle cell trait carriers.

    PubMed

    Vayá, Amparo; Collado, Susana; Alis, Rafael; Vera, Belen; Romagnoli, Marco; Barragán, Eva

    2014-01-01

    Studies dealing with rheological red blood cell (RBC) behavior in sickle cell trait carriers are scarce. Moreover, the association with α-thalassemia (α-thal), which also modifies erythrocyte behavior, has not always been taken into account. We analyzed erythrocyte deformability by means of a shear stress diffractometer, along with hematological and biochemical parameters (glucose and plasma lipids), given their possible influence on erythrocyte deformability, in 14 sickle cell trait carriers and 23 healthy controls. Nine patients were also α-thal carriers and five were not. Among the thalassemia carriers, eight were heterozygous and one was homozygous. When compared with controls, sickle cell trait carriers showed no differences for any of the biochemical parameters analyzed (p > 0.05), but significantly lower hemoglobin (Hb) (p = 0.003), mean corpuscular volume (MCV) and mean corpuscular Hb (MCH) (p < 0.001) levels, although no differences in erythrocyte deformability were observed at any of the shear stresses tested (p > 0.05). When comparing sickle cell trait carriers, with and without α-thal, no differences in erythrocyte deformability were observed (p > 0.05), in spite of the former showing lower MCV and MCH (p < 0.05) levels. Carriers of α-thal had lower Hb S [β6(A3)Glu → Val; HBB: c.20A > T] levels (p = 0.013) than non carriers. The existence of a compensating mechanism seems reasonable because, despite presenting lower erythrocyte indices, which could worsen erythrocyte deformability, this rheological property improves when the percentage of Hb S is lower. PMID:24601859

  14. Influence of NO-containing gas flow on various parameters of energy metabolism in erythrocytes.

    PubMed

    Martusevich, A K; Solov'yova, A G; Peretyagin, S P; Karelin, V I; Selemir, V D

    2014-11-01

    We studied the influence of NO-containing gas phase on some parameters of energy metabolism in human erythrocytes. Whole blood samples were aerated with gas flows from the Plazon instrument (NO concentrations 800 and 80 ppm) and from the experimental generator (75 ppm). Activity of lactate dehydrogenase in direct and reverse reactions, lactate level, and a number of derived coefficients were estimated. Treatment of blood with 800 ppm NO inhibited erythrocyte energy metabolism, and its 10-fold dilution attenuated the effect. The use of ROS-free gas flow containing 75 ppm of NO promoted optimization of the process under investigation.

  15. Influence of NO-containing gas flow on various parameters of energy metabolism in erythrocytes.

    PubMed

    Martusevich, A K; Solov'yova, A G; Peretyagin, S P; Karelin, V I; Selemir, V D

    2014-11-01

    We studied the influence of NO-containing gas phase on some parameters of energy metabolism in human erythrocytes. Whole blood samples were aerated with gas flows from the Plazon instrument (NO concentrations 800 and 80 ppm) and from the experimental generator (75 ppm). Activity of lactate dehydrogenase in direct and reverse reactions, lactate level, and a number of derived coefficients were estimated. Treatment of blood with 800 ppm NO inhibited erythrocyte energy metabolism, and its 10-fold dilution attenuated the effect. The use of ROS-free gas flow containing 75 ppm of NO promoted optimization of the process under investigation. PMID:25403392

  16. Influence of the glycocalyx and plasma membrane composition on amphiphilic gold nanoparticle association with erythrocytes.

    PubMed

    Atukorale, Prabhani U; Yang, Yu-Sang; Bekdemir, Ahmet; Carney, Randy P; Silva, Paulo J; Watson, Nicki; Stellacci, Francesco; Irvine, Darrell J

    2015-07-14

    Erythrocytes are attractive as potential cell-based drug carriers because of their abundance and long lifespan in vivo. Existing methods for loading drug cargos into erythrocytes include hypotonic treatments, electroporation, and covalent attachment onto the membrane, all of which require ex vivo manipulation. Here, we characterized the properties of amphiphilic gold nanoparticles (amph-AuNPs), comprised of a ∼2.3 nm gold core and an amphiphilic ligand shell, which are able to embed spontaneously within erythrocyte membranes and might provide a means to load drugs into red blood cells (RBCs) directly in vivo. Particle interaction with RBC membranes occurred rapidly at physiological temperature. We further show that amph-AuNP uptake by RBCs was limited by the glycocalyx and was particularly influenced by sialic acids on cell surface proteoglycans. Using a reductionist model membrane system with synthetic lipid vesicles, we confirmed the importance of membrane fluidity and the glycocalyx in regulating amph-AuNP/membrane interactions. These results thus provide evidence for the interaction of amph-AuNPs with erythrocyte membranes and identify key membrane components that govern this interaction, providing a framework for the development of amph-AuNP-carrying erythrocyte 'pharmacytes' in vivo.

  17. Influence of magnesium sulfate on HCO3/Cl transmembrane exchange rate in human erythrocytes.

    PubMed

    Chernyshova, Ekaterina S; Zaikina, Yulia S; Tsvetovskaya, Galina A; Strokotov, Dmitry I; Yurkin, Maxim A; Serebrennikova, Elena S; Volkov, Leonid; Maltsev, Valeri P; Chernyshev, Andrei V

    2016-03-21

    Magnesium sulfate (MgSO4) is widely used in medicine but molecular mechanisms of its protection through influence on erythrocytes are not fully understood and are considerably controversial. Using scanning flow cytometry, in this work for the first time we observed experimentally (both in situ and in vitro) a significant increase of HCO3(-)/Cl(-) transmembrane exchange rate of human erythrocytes in the presence of MgSO4 in blood. For a quantitative analysis of the obtained experimental data, we introduced and verified a molecular kinetic model, which describes activation of major anion exchanger Band 3 (or AE1) by its complexation with free intracellular Mg(2+) (taking into account Mg(2+) membrane transport and intracellular buffering). Fitting the model to our in vitro experimental data, we observed a good correspondence between theoretical and experimental kinetic curves that allowed us to evaluate the model parameters and to estimate for the first time the association constant of Mg(2+) with Band 3 as KB~0.07mM, which is in agreement with known values of the apparent Mg(2+) dissociation constant (from 0.01 to 0.1mM) that reflects experiments on enrichment of Mg(2+) at the inner erythrocyte membrane (Gunther, 2007). Results of this work partly clarify the molecular mechanisms of MgSO4 action in human erythrocytes. The method developed allows one to estimate quantitatively a perspective of MgSO4 treatment for a patient. It should be particularly helpful in prenatal medicine for early detection of pathologies associated with the risk of fetal hypoxia.

  18. Influence of glucose concentration on the membrane stability of human erythrocytes.

    PubMed

    Lemos, Guilherme Santos Duarte; Márquez-Bernardes, Liandra Freitas; Arvelos, Letícia Ramos; Paraíso, Lara Ferreira; Penha-Silva, Nilson

    2011-12-01

    The action of glucose as an osmolyte in relation to blood cells is not well-characterized in the literature. This study aimed to study the influence of glucose concentration on the stability of red blood cells. The stability of erythrocytes was evaluated by the half-transition point obtained from the curves of lysis induced by glucose in the absence of salt or by increase in medium hypotonicity in the absence and the presence of different concentrations of glucose. In the presence of 0.9 g/dl NaCl, there was no hemolysis with increasing concentration of glucose from 0 to 10 g/dl. In the absence of NaCl, the dependence of hemolysis with the 0-10 g/dl glucose was described by a decreasing sigmoid, with fully lysed and fully protected cells being encountered in the presence of 0-2 and 4-10 g/dl glucose, respectively. The possible origin of such stabilization effect is discussed with base of what is known about osmostabilization of biological complexes and about the influence of glucose on the rheological properties of erythrocytes. PMID:21735128

  19. Microsphiltration: a microsphere matrix to explore erythrocyte deformability.

    PubMed

    Lavazec, Catherine; Deplaine, Guillaume; Safeukui, Innocent; Perrot, Sylvie; Milon, Geneviève; Mercereau-Puijalon, Odile; David, Peter H; Buffet, Pierre

    2013-01-01

    The altered deformability of erythrocytes infected with Plasmodium falciparum is central in malaria -pathogenesis, as it influences the hemodynamic properties of the infected cell and its retention in the spleen. Exported parasite proteins, as well as the shape and volume of the parasite itself, influence the deformability of the infected erythrocyte. To explore changes in erythrocyte deformability, we have developed a new method, called microsphiltration, based on filtration of erythrocytes through a mixture of metal microspheres that mimic the geometry of inter-endothelial splenic slits. As P. falciparum develops in its host cell, the retention rates observed in microspheres correlate with the progressive decrease of erythrocyte deformability and with the retention rates in the spleen. The yields of microsphiltration separation allow for molecular analyses of subpopulations with distinct mechanical phenotypes.

  20. Selenium Deficiency Influences the mRNA Expression of Selenoproteins and Cytokines in Chicken Erythrocytes.

    PubMed

    Luan, Yilin; Zhao, Jinxin; Yao, Haidong; Zhao, Xia; Fan, Ruifeng; Zhao, Wenchao; Zhang, Ziwei; Xu, Shiwen

    2016-06-01

    Selenium (Se) deficiency induces hemolysis in chickens, but the molecular mechanism for this effect remains unclear. Se primarily elicits its function through the activity of selenoproteins, which contain the unique amino acid selenocysteine (Sec). In this study, we aimed to investigate the effect of Se deficiency on the expression of 24 selenoproteins and 10 cytokines. One hundred eighty chickens were randomly divided into 2 groups (90 chickens per group). During the entire experimental period, chickens were allowed ad libitum consumption of feed and water. The chickens were fed either a Se-deficient diet (0.008 mg Se/kg; produced in the Se-deficient area of Heilongjiang, China) or a Se-supplemented diet (as sodium selenite) at 0.2 mg/kg for 35 days. At the 35th day, the messenger RNA (mRNA) levels of 24 selenoproteins and 10 cytokines were examined in erythrocytes of 5 chickens per group, and the correlation was analyzed. The results showed that the expression of 24 selenoproteins and 7 cytokines (IL-2, IL-4, IL-8, IL-10, IL-12β, TGF-β4, and IFN-γ) decreased (P < 0.05), and the expression of 3 cytokines (IL-1γ, IL-6 and IL-7) was higher in the Se-deficient group. In both groups, glutathione peroxidase (GPX), thioredoxin 1 (Txnrd1), selenoprotein P1 (SELP), and selenoprotein synthetase (SPS2) were highly expressed compared to the other selenoproteins in chicken erythrocytes (P < 0.05). These data suggest that GPXs, Txnrd1, SELP, and SPS2 possibly play a more important role than the other selenoproteins. The increase of pro-inflammatory cytokines (IL-1γ, IL-6, and IL-7) suggested that the immune system of chickens was damaged by the Se deficiency. Correlation analysis suggested that although the expression of 24 selenoproteins and 7 cytokines decreased and that of 3 cytokines increased, there was a close correlation between their expression levels and a Se diet. These results suggested that Se deficiency influenced the expressions of 24 selenoproteins

  1. Influence of erythrocyte iodothyronine-binding proteins on radioimmunoassay of thyroxin in dried blood spots

    SciTech Connect

    Sadler, W.A.; Lynskey, C.P.

    1982-01-01

    Three erythrocyte proteins, one identified as hemoglobin, bind thyroid hormones. Using a dextran/charcoal radioimmunoassay for thyroxin in dried blood spots, we demonstrate that such binding differs with the buffer used. Barbital, phosphate, and borate buffers significantly enhance the binding more than glycine and tris(hydroxymethyl)methylamine buffers. Binding is not affected by agents commonly used to inhibit thyroxin binding to serum proteins. A highly significant nonlinear direct relationship between sample storage (temperature and duration) and increased thyroxin-erythrocyte binding is documented, together with an associated decrease in assayed concentrations of thyroxin. However, concomitant serial measurement of thyroxin with polyethylene glycol and combined double-antibody/polyethylene glycol radioimmunoassays produced no evidence of interference by erythrocyte proteins in the radioimmune reaction. We conclude that erythrocyte proteins act only as low-affinity secondary binders in radioimmunoassay for thyroxin.

  2. The influence of erythrocyte maturity on ion transport and membrane lipid composition in the rat.

    PubMed

    Vokurková, M; Rauchová, H; Dobešová, Z; Loukotová, J; Nováková, O; Kuneš, J; Zicha, J

    2016-01-01

    Significant relationships between ion transport and membrane lipid composition (cholesterol, total phospholipids and sphingomyelins) were found in erythrocytes of salt hypertensive Dahl rats. In these animals mean cellular hemoglobin content correlated negatively with Na(+)-K(+) pump activity and Na(+) leak but positively with Na(+)-K(+) cotransport activity. Immature erythrocytes exhibit lower mean cellular hemoglobin content (MCHC) than mature ones. The aim of the present study was to find a relationship between erythrocyte maturity, membrane lipid composition and ion transport activity in Wistar rats aged three months which were subjected to repeated hemorrhage (blood loss 2 ml/day for 6 days) to enrich circulating erythrocytes with immature forms. Immature and mature erythrocyte fractions in control and hemorrhaged rats were separated by repeated centrifugation. Hemorrhaged rats had increased number of reticulocytes but reduced hematocrit and MCHC compared to control rats. Immature erythrocytes of hemorrhaged rats differed from mature ones of control animals by elevated Na(+)-K(+) pump activity, reduced Na(+)-K(+) cotransport activity and increased Rb(+) leak. These ion transport changes in immature erythrocytes were accompanied by higher concentration of total phospholipids in their cell membranes. Membrane phospholipid content correlated positively with Na(+)-K(+) pump activity and cation leaks but negatively with Na(+)-K(+) cotransport activity. Moreover, they were also negatively related with MCHC which correlated negatively with Na(+)-K(+) pump activity and Rb(+) leak but positively with Na(+)-K(+) cotransport activity. Thus certain abnormalities of erythrocyte ion transport and membrane lipid composition detected in hypertensive animals might be caused by higher incidence of immature cells. PMID:26988297

  3. Influence of Cocoa Flavanols and Procyanidins on Free Radical-induced Human Erythrocyte Hemolysis

    PubMed Central

    Zhu, Qin Yan; Schramm, Derek D.; Gross, Heidrun B.; Holt, Roberta R.; Kim, Sun H.; Yamaguchi, Tomoko; Kwik-Uribe, Catherine L.; Keen, Carl L.

    2005-01-01

    Cocoa can be a rich source of antioxidants including the flavan-3-ols, epicatechin and catechin, and their oligomers (procyanidins). While these flavonoids have been reported to reduce the rate of free radical-induced erythrocyte hemolysis in experimental animal models, little is known about their effect on human erythrocyte hemolysis. The major objective of this work was to study the effect of a flavonoid-rich cocoa beverage on the resistance of human erythrocytes to oxidative stress. A second objective was to assess the effects of select purified cocoa flavonoids, epicatechin, catechin, the procyanidin Dimer B2 and one of its major metabolites, 3ʹ-O-methyl epicatechin, on free radical-induced erythrocyte hemolysis in vitro. Peripheral blood was obtained from 8 healthy subjects before and 1, 2, 4 and 8 h after consuming a flavonoid-rich cocoa beverage that provided 0.25 g/kg body weight (BW), 0.375 or 0.50 g/kg BW of cocoa. Plasma flavanol and dimer concentrations were determined for each subject. Erythrocyte hemolysis was evaluated using a controlled peroxidation reaction. Epicatechin, catechin, 3ʹ-O-methyl epicatechin and (-)-epicatechin-(4β > 8)epicatechin (Dimer B2) were detected in the plasma within 1 h after the consumption of the beverage. The susceptibility of erythrocytes to hemolysis was reduced significantly following the consumption of the beverages. The duration of the lag time, which reflects the capacity of cells to buffer free radicals, was increased. Consistent with the above, the purified flavonoids, epicatechin, catechin, Dimer B2 and the metabolite 3ʹ-O-methyl epicatechin, exhibited dose-dependent protection against AAPH-induced erythrocyte hemolysis at concentrations ranging from 2.5 to 20 μM. Erythrocytes from subjects consuming flavonoid-rich cocoa show reduced susceptibility to free radical-induced hemolysis (p < 0.05). PMID:15712596

  4. Influence of ethanolic extract of Tephrosia purpurea Linn. on mast cells and erythrocytes membrane integrity.

    PubMed

    Gokhale, A B; Dikshit, V J; Damre, A S; Kulkarni, K R; Saraf, M N

    2000-08-01

    The ethanolic extract of T. purpurea Linn. was studied for its in vitro effect on rat mast cell degranulation and erythrocyte membrane integrity in vitro. The extract in concentration of 25-200 microg/ml showed a dose-dependant inhibition of rat mast cell degranulation induded by compound 48/80 and egg albumin. T. purpurea extract was found to inhibit haemolysis of erythrocytes induced by hypotonic solution but accelerated haemolysis induced by heat at a concentration of 100 microg/ml. The studies reveal that the ethanolic extract of T. purpurea may inhibit degranulation of mast cells by a mechanism other than membrane stabilization.

  5. On the cellular autoimmune mechanism for eliminating erythrocytes normally and under extreme influences

    NASA Technical Reports Server (NTRS)

    Pukhova, Y. I.; Terskov, I. A.; Anikina, A. Y.; Shashkin, A. V.

    1980-01-01

    The presence of an autoimmune cellular mechanism for destroying erythrocytes on the basis of results of experiments in vivo is demonstrated in the blood and the organs. This mechanism is made up of a population of immunocompetent killer-lymphocytes which originates in the bone marrow and the thymus, and which is manifested in the local hemolysis effect.

  6. Influence of acute exercise on the osmotic stability of the human erythrocyte membrane.

    PubMed

    Paraiso, L F; de Freitas, M V; Gonçalves-E-Oliveira, A F M; de Almeida Neto, O P; Pereira, E A; Mascarenhas Netto, R C; Cunha, L M; Bernardino Neto, M; de Agostini, G G; Resende, E S; Penha-Silva, N

    2014-12-01

    This study evaluated the effects of 2 different types of acute aerobic exercise on the osmotic stability of human erythrocyte membrane and on different hematological and biochemical variables that are associated with this membrane property. The study population consisted of 20 healthy and active men. Participants performed single sessions of 2 types of exercise. The first session consisted of 60 min of moderate-intensity continuous exercise (MICE). The second session, executed a week later, consisted of high-intensity interval exercise (HIIE) until exhaustion. The osmotic stability of the erythrocyte membrane was represented by the inverse of the salt concentration (1/H50) at the midpoint of the sigmoidal curve of dependence between the absorbance of hemoglobin and the NaCl concentration. The values of 1/H50 changed from 2.29±0.1 to 2.33±0.09 after MICE and from 2.30±0.08 to 2.23±0.12 after HIIE. During MICE mean corpuscular volume increased, probably due to in vivo lysis of older erythrocytes, with preservation of cells that were larger and more resistant to in vitro lysis. The study showed that a single bout of acute exercise affected erythrocyte stability, which increased after MICE and decreased after HIIE.

  7. Detection of erythrocytes influenced by aging and type 2 diabetes using atomic force microscope

    SciTech Connect

    Jin, Hua; Xing, Xiaobo; Zhao, Hongxia; Chen, Yong; Huang, Xun; Ma, Shuyuan; Ye, Hongyan; Cai, Jiye

    2010-01-22

    The pathophysiological changes of erythrocytes are detected at the molecular scale, which is important to reveal the onset of diseases. Type 2 diabetes is an age-related metabolic disorder with high prevalence in elderly (or old) people. Up to now, there are no treatments to cure diabetes. Therefore, early detection and the ability to monitor the progression of type 2 diabetes are very important for developing effective therapies. Type 2 diabetes is associated with high blood glucose in the context of insulin resistance and relative insulin deficiency. These abnormalities may disturb the architecture and functions of erythrocytes at molecular scale. In this study, the aging- and diabetes-induced changes in morphological and biomechanical properties of erythrocytes are clearly characterized at nanometer scale using atomic force microscope (AFM). The structural information and mechanical properties of the cell surface membranes of erythrocytes are very important indicators for determining the healthy, diseased or aging status. So, AFM may potentially be developed into a powerful tool in diagnosing diseases.

  8. Skeletal muscle calcineurin: influence of phenotype adaptation and atrophy

    NASA Technical Reports Server (NTRS)

    Spangenburg, E. E.; Williams, J. H.; Roy, R. R.; Talmadge, R. J.; Spangenberg, E. E. (Principal Investigator)

    2001-01-01

    Calcineurin (CaN) has been implicated as a signaling molecule that can transduce physiological stimuli (e.g., contractile activity) into molecular signals that initiate slow-fiber phenotypic gene expression and muscle growth. To determine the influence of muscle phenotype and atrophy on CaN levels in muscle, the levels of soluble CaN in rat muscles of varying phenotype, as assessed by myosin heavy chain (MHC)-isoform proportions, were determined by Western blotting. CaN levels were significantly greater in the plantaris muscle containing predominantly fast (IIx and IIb) MHC isoforms, compared with the soleus (predominantly type I MHC) or vastus intermedius (VI, contains all 4 adult MHC isoforms). Three months after a complete spinal cord transection (ST), the CaN levels in the VI muscle were significantly reduced, despite a significant increase in fast MHC isoforms. Surprisingly, the levels of CaN in the VI were highly correlated with muscle mass but not MHC isoform proportions in ST and control rats. These data demonstrate that CaN levels in skeletal muscle are highly correlated to muscle mass and that the normal relationship with phenotype is lost after ST.

  9. X-chromosomal inactivation directly influences the phenotypic manifestation of X-linked protoporphyria.

    PubMed

    Brancaleoni, V; Balwani, M; Granata, F; Graziadei, G; Missineo, P; Fiorentino, V; Fustinoni, S; Cappellini, M D; Naik, H; Desnick, R J; Di Pierro, E

    2016-01-01

    X-linked protoporphyria (XLP), a rare erythropoietic porphyria, results from terminal exon gain-of-function mutations in the ALAS2 gene causing increased ALAS2 activity and markedly increased erythrocyte protoporphyrin levels. Patients present with severe cutaneous photosensitivity and may develop liver dysfunction. XLP was originally reported as X-linked dominant with 100% penetrance in males and females. We characterized 11 heterozygous females from six unrelated XLP families and show markedly varying phenotypic and biochemical heterogeneity, reflecting the degree of X-chromosomal inactivation of the mutant gene. ALAS2 sequencing identified the specific mutation and confirmed heterozygosity among the females. Clinical history, plasma and erythrocyte protoporphyrin levels were determined. Methylation assays of the androgen receptor and zinc-finger MYM type 3 short tandem repeat polymorphisms estimated each heterozygotes X-chromosomal inactivation pattern. Heterozygotes with equal or increased skewing, favoring expression of the wild-type allele had no clinical symptoms and only slightly increased erythrocyte protoporphyrin concentrations and/or frequency of protoporphyrin-containing peripheral blood fluorocytes. When the wild-type allele was preferentially inactivated, heterozygous females manifested the disease phenotype and had both higher erythrocyte protoporphyrin levels and circulating fluorocytes. These findings confirm that the previous dominant classification of XLP is inappropriate and genetically misleading, as the disorder is more appropriately designated XLP.

  10. [The influence of extracorporeal laser radiation on structural indices of erythrocytes].

    PubMed

    Khetsuriani, R G; Aladashvili, L M; Arabuli, M B; Tophuria, D Z; Tchlikadze, N G

    2015-01-01

    Object of the research was to study the diffractometric indices of erythrocytes, while 1 ml of the blood of the experimental animals was irradiated extracorporally by helium-neon laser. For this purpose 1 ml blood was taken from normal weight, (1200 gr) grown up shinshila rabbits, that we divided into 7 groups and irradiated with 10 vat helium-neon laser during 0.5-1 minutes. After irradiation blood was injected back to the organism of rabbits. After 2-6 hours from irradiation blood was taken from veins, to study by electronic microscope and later to be processed by diffractometric analysis method. The examinations testify that after extracorporeal irradiation diffractometric characteristics of erythrocytes' membranes are lower than after general irradiation, which indicates to the different energetic possibilities of laser. The extracorporeal irradiation, performed by laser and input of radiated blood back to organism is considered to be a shock therapy from the side of erythrocytes, which promote the defense function of the organism itself. The base for the shock therapy should be important factors such as homeostasis, compensative-adaptive mechanisms and so on. Exactly this above mentioned should be manifested after the sensitized cells are led back to the body (1 ml of blood) and with their existence they should promote display of the defense mechanisms. PMID:25693223

  11. The influence of the microenvironment on the malignant phenotype

    NASA Technical Reports Server (NTRS)

    Park, C. C.; Bissell, M. J.; Barcellos-Hoff, M. H.

    2000-01-01

    Normal tissue homeostasis is maintained by dynamic interactions between epithelial cells and their microenvironment. As tissue becomes cancerous, there are reciprocal interactions between neoplastic cells, adjacent normal cells such as stroma and endothelium, and their microenvironments. The current dominant paradigm wherein multiple genetic lesions provide both the impetus for, and the Achilles heel of, cancer might be inadequate to understand cancer as a disease process. In the following brief review, we will use selected examples to illustrate the influence of the microenvironment in the evolution of the malignant phenotype. We will also discuss recent studies that suggest novel therapeutic interventions might be derived from focusing on microenvironment and tumor cells interactions.

  12. Host Erythrocyte Environment Influences the Localization of Exported Protein 2, an Essential Component of the Plasmodium Translocon

    PubMed Central

    Meibalan, Elamaran; Comunale, Mary Ann; Lopez, Ana M.; Bergman, Lawrence W.; Mehta, Anand; Vaidya, Akhil B.

    2015-01-01

    Malaria parasites replicating inside red blood cells (RBCs) export a large subset of proteins into the erythrocyte cytoplasm to facilitate parasite growth and survival. PTEX, the parasite-encoded translocon, mediates protein transport across the parasitophorous vacuolar membrane (PVM) in Plasmodium falciparum-infected erythrocytes. Proteins exported into the erythrocyte cytoplasm have been localized to membranous structures, such as Maurer's clefts, small vesicles, and a tubovesicular network. Comparable studies of protein trafficking in Plasmodium vivax-infected reticulocytes are limited. With Plasmodium yoelii-infected reticulocytes, we identified exported protein 2 (Exp2) in a proteomic screen of proteins putatively transported across the PVM. Immunofluorescence studies showed that P. yoelii Exp2 (PyExp2) was primarily localized to the PVM. Unexpectedly, PyExp2 was also associated with distinct, membrane-bound vesicles in the reticulocyte cytoplasm. This is in contrast to P. falciparum in mature RBCs, where P. falciparum Exp2 (PfExp2) is exclusively localized to the PVM. Two P. yoelii-exported proteins, PY04481 (encoded by a pyst-a gene) and PY06203 (PypAg-1), partially colocalized with these PyExp2-positive vesicles. Further analysis revealed that with P. yoelii, Plasmodium berghei, and P. falciparum, cytoplasmic Exp2-positive vesicles were primarily observed in CD71+ reticulocytes versus mature RBCs. In transgenic P. yoelii 17X parasites, the association of hemagglutinin-tagged PyExp2 with the PVM and cytoplasmic vesicles was retained, but the pyexp2 gene was refractory to deletion. These data suggest that the localization of Exp2 in mouse and human RBCs can be influenced by the host cell environment. Exp2 may function at multiple points in the pathway by which parasites traffic proteins into and through the reticulocyte cytoplasm. PMID:25662767

  13. The influence of merocyanine 540 and protoporphyrin on physicochemical properties of the erythrocyte membrane.

    PubMed

    Lagerberg, J W; Williams, M; Moor, A C; Brand, A; van der Zee, J; Dubbelman, T M; VanSteveninck, J

    1996-01-31

    The interaction of the red cell membrane with merocyanine 540 or protoporphyrin led to four phenomena, most probably interrelated. (i) The morphology changed from the normal discoid to an echinocytic form. This morphological change persisted when followed over a period of 24 h. (ii) Simultaneously, cell deformability was decreased, as revealed by viscosity measurements and a cell-filtration technique. (iii) Both drugs caused swelling of the erythrocytes in isotonic medium, due to a very-short-term increased permeability of the membrane, also for larger molecules such as lactose. The pathway of this temporary leak seems to be unrelated to the Na+/K+ -ATPase, the K+/Cl- and the Na+/K+/Cl- cotransport systems, the Ca2+-activated Gardos pathway, the oxidation/deformation-activated leak pathway and the so-called residual transport route. Despite the morphological changes, K+-leakage induced by mechanical stress was not increased. (iv) During osmotic swelling, the critical hemolytic volume was found to be increased in the presence of either merocyanine 540 or protoporphyrin. The increase critical volume protected erythrocytes against osmotic hemolysis. PMID:8593283

  14. Rosetting Plasmodium falciparum-infected erythrocytes bind to human brain microvascular endothelial cells in vitro, demonstrating a dual adhesion phenotype mediated by distinct P. falciparum erythrocyte membrane protein 1 domains.

    PubMed

    Adams, Yvonne; Kuhnrae, Pongsak; Higgins, Matthew K; Ghumra, Ashfaq; Rowe, J Alexandra

    2014-03-01

    Adhesion interactions between Plasmodium falciparum-infected erythrocytes (IE) and human cells underlie the pathology of severe malaria. IE cytoadhere to microvascular endothelium or form rosettes with uninfected erythrocytes to survive in vivo by sequestering IE in the microvasculature and avoiding splenic clearance mechanisms. Both rosetting and cytoadherence are mediated by the parasite-derived IE surface protein family Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). Rosetting and cytoadherence have been widely studied as separate entities; however, the ability of rosetting P. falciparum strains to cytoadhere has received little attention. Here, we show that IE of the IT/R29 strain expressing a rosette-mediating PfEMP1 variant (IT4var09) cytoadhere in vitro to a human brain microvascular endothelial cell line (HBEC-5i). Cytoadherence was inhibited by heparin and by treatment of HBEC-5i with heparinase III, suggesting that the endothelial receptors for IE binding are heparan sulfate proteoglycans. Antibodies to the N-terminal regions of the IT4var09 PfEMP1 variant (NTS-DBL1α and DBL2γ domains) specifically inhibited and reversed cytoadherence down to low concentrations (<10 μg/ml of total IgG). Surface plasmon resonance experiments showed that the NTS-DBLα and DBL2γ domains bind strongly to heparin, with half-maximal binding at a concentration of ∼0.5 μM in both cases. Therefore, cytoadherence of IT/R29 IE is distinct from rosetting, which is primarily mediated by NTS-DBL1α interactions with complement receptor 1. These data show that IT4var09-expressing parasites are capable of dual interactions with both endothelial cells and uninfected erythrocytes via distinct receptor-ligand interactions.

  15. Circadian blood pressure variability in type 1 diabetes subjects and their nondiabetic siblings - influence of erythrocyte electron transfer

    PubMed Central

    2010-01-01

    Background Normotensive non-diabetic relatives of type 1 diabetes (T1D) patients have an abnormal blood pressure response to exercise testing that is associated with indices of metabolic syndrome and increased oxidative stress. The primary aim of this study was to investigate the circadian variability of blood pressure and the ambulatory arterial stiffness index (AASI) in healthy siblings of T1D patients vs healthy control subjects who had no first-degree relative with T1D. Secondary aims of the study were to explore the influence of both cardiovascular autonomic function and erythrocyte electron transfer activity as oxidative marker on the ambulatory blood pressure profile. Methods Twenty-four hour ambulatory blood pressure monitoring (ABPM) was undertaken in 25 controls, 20 T1D patients and 20 siblings. In addition to laboratory examination (including homeostasis model assessment of insulin sensitivity) and clinical testing of autonomic function, we measured the rate of oxidant-induced erythrocyte electron transfer to extracellular ferricyanide (RBC vfcy). Results Systolic blood pressure (SBP) midline-estimating statistic of rhythm and pulse pressure were higher in T1D patients and correlated positively with diabetes duration and RBC vfcy; autonomic dysfunction was associated with diastolic BP ecphasia and increased AASI. Siblings had higher BMI, lower insulin sensitivity, larger SBP amplitude, and higher AASI than controls. Daytime SBP was positively, independently associated with BMI and RBC vfcy. Among non-diabetic people, there was a significant correlation between AASI and fasting plasma glucose. Conclusions Siblings of T1D patients exhibited a cluster of sub-clinical metabolic abnormalities associated with consensual perturbations in BP variability. Moreover, our findings support, in a clinical setting, the proposed role of transplasma membrane electron transport systems in vascular pathobiology. PMID:20920366

  16. Rumen microbial communities influence metabolic phenotypes in lambs

    PubMed Central

    Morgavi, Diego P.; Rathahao-Paris, Estelle; Popova, Milka; Boccard, Julien; Nielsen, Kristian F.; Boudra, Hamid

    2015-01-01

    The rumen microbiota is an essential part of ruminants shaping their nutrition and health. Despite its importance, it is not fully understood how various groups of rumen microbes affect host-microbe relationships and functions. The aim of the study was to simultaneously explore the rumen microbiota and the metabolic phenotype of lambs for identifying host-microbe associations and potential biomarkers of digestive functions. Twin lambs, separated in two groups after birth were exposed to practices (isolation and gavage with rumen fluid with protozoa or protozoa-depleted) that differentially restricted the acquisition of microbes. Rumen microbiota, fermentation parameters, digestibility and growth were monitored for up to 31 weeks of age. Microbiota assembled in isolation from other ruminants lacked protozoa and had low bacterial and archaeal diversity whereas digestibility was not affected. Exposure to adult sheep microbiota increased bacterial and archaeal diversity independently of protozoa presence. For archaea, Methanomassiliicoccales displaced Methanosphaera. Notwithstanding, protozoa induced differences in functional traits such as digestibility and significantly shaped bacterial community structure, notably Ruminococcaceae and Lachnospiraceae lower up to 6 folds, Prevotellaceae lower by ~40%, and Clostridiaceae and Veillonellaceae higher up to 10 folds compared to microbiota without protozoa. An orthogonal partial least squares-discriminant analysis of urinary metabolome matched differences in microbiota structure. Discriminant metabolites were mainly involved in amino acids and protein metabolic pathways while a negative interaction was observed between methylotrophic methanogens Methanomassiliicoccales and trimethylamine N-oxide. These results stress the influence of gut microbes on animal phenotype and show the potential of metabolomics for monitoring rumen microbial functions. PMID:26528248

  17. Rumen microbial communities influence metabolic phenotypes in lambs.

    PubMed

    Morgavi, Diego P; Rathahao-Paris, Estelle; Popova, Milka; Boccard, Julien; Nielsen, Kristian F; Boudra, Hamid

    2015-01-01

    The rumen microbiota is an essential part of ruminants shaping their nutrition and health. Despite its importance, it is not fully understood how various groups of rumen microbes affect host-microbe relationships and functions. The aim of the study was to simultaneously explore the rumen microbiota and the metabolic phenotype of lambs for identifying host-microbe associations and potential biomarkers of digestive functions. Twin lambs, separated in two groups after birth were exposed to practices (isolation and gavage with rumen fluid with protozoa or protozoa-depleted) that differentially restricted the acquisition of microbes. Rumen microbiota, fermentation parameters, digestibility and growth were monitored for up to 31 weeks of age. Microbiota assembled in isolation from other ruminants lacked protozoa and had low bacterial and archaeal diversity whereas digestibility was not affected. Exposure to adult sheep microbiota increased bacterial and archaeal diversity independently of protozoa presence. For archaea, Methanomassiliicoccales displaced Methanosphaera. Notwithstanding, protozoa induced differences in functional traits such as digestibility and significantly shaped bacterial community structure, notably Ruminococcaceae and Lachnospiraceae lower up to 6 folds, Prevotellaceae lower by ~40%, and Clostridiaceae and Veillonellaceae higher up to 10 folds compared to microbiota without protozoa. An orthogonal partial least squares-discriminant analysis of urinary metabolome matched differences in microbiota structure. Discriminant metabolites were mainly involved in amino acids and protein metabolic pathways while a negative interaction was observed between methylotrophic methanogens Methanomassiliicoccales and trimethylamine N-oxide. These results stress the influence of gut microbes on animal phenotype and show the potential of metabolomics for monitoring rumen microbial functions. PMID:26528248

  18. Prediabetes Phenotype Influences Improvements in Glucose Homeostasis with Resistance Training

    PubMed Central

    Eikenberg, Joshua D.; Savla, Jyoti; Marinik, Elaina L.; Davy, Kevin P.; Pownall, John; Baugh, Mary E.; Flack, Kyle D.; Boshra, Soheir; Winett, Richard A.; Davy, Brenda M.

    2016-01-01

    Purpose To determine if prediabetes phenotype influences improvements in glucose homeostasis with resistance training (RT). Methods Older, overweight individuals with prediabetes (n = 159; aged 60±5 yrs; BMI 33±4 kg/m2) completed a supervised RT program twice per week for 12 weeks. Body weight and composition, strength, fasting plasma glucose, 2-hr oral glucose tolerance, and Matsuda-Defronza estimated insulin sensitivity index (ISI) were assessed before and after the intervention. Participants were categorized according to their baseline prediabetes phenotype as impaired fasting glucose only (IFG) (n = 73), impaired glucose tolerance only (IGT) (n = 21), or combined IFG and IGT (IFG/IGT) (n = 65). Results Chest press and leg press strength increased 27% and 18%, respectively, following the 12-week RT program (both p<0.05). Waist circumference (-1.0%; pre 109.3±10.3 cm, post 108.2±10.6 cm) and body fat (-0.6%; pre 43.7±6.8%, post 43.1±6.8%) declined, and lean body mass (+1.3%; pre 52.0±10.4 kg, post 52.7±10.7 kg) increased following the intervention. Fasting glucose concentrations did not change (p>0.05) following the intervention. However, 2-hr oral glucose tolerance improved in those with IGT (pre 8.94±0.72 mmol/l, post 7.83±1.11 mmol/l, p<0.05) and IFG/IGT (pre 9.66±1.11mmol/l, post 8.60±2.00 mmol/l) but not in those with IFG (pre 6.27±1.28mmol/l, post 6.33± 1.55 mmol/l). There were no significant changes in ISI or glucose area under the curve following the RT program. Conclusions RT without dietary intervention improves 2-hr oral glucose tolerance in individuals with prediabetes. However, the improvements in glucose homeostasis with RT appear limited to those with IGT or combined IFG and IGT. Trial Registration ClinicalTrials.gov: NCT01112709 PMID:26840904

  19. The Cell Adhesion Molecule “CAR” and Sialic Acid on Human Erythrocytes Influence Adenovirus In Vivo Biodistribution

    PubMed Central

    Wodrich, Harald; Billet, Olivier; Perreau, Matthieu; Hippert, Claire; Mennechet, Franck; Schoehn, Guy; Lortat-Jacob, Hugues; Dreja, Hanna; Ibanes, Sandy; Kalatzis, Vasiliki; Wang, Jennifer P.; Finberg, Robert W.; Cusack, Stephen; Kremer, Eric J.

    2009-01-01

    Although it has been known for 50 years that adenoviruses (Ads) interact with erythrocytes ex vivo, the molecular and structural basis for this interaction, which has been serendipitously exploited for diagnostic tests, is unknown. In this study, we characterized the interaction between erythrocytes and unrelated Ad serotypes, human 5 (HAd5) and 37 (HAd37), and canine 2 (CAV-2). While these serotypes agglutinate human erythrocytes, they use different receptors, have different tropisms and/or infect different species. Using molecular, biochemical, structural and transgenic animal-based analyses, we found that the primary erythrocyte interaction domain for HAd37 is its sialic acid binding site, while CAV-2 binding depends on at least three factors: electrostatic interactions, sialic acid binding and, unexpectedly, binding to the coxsackievirus and adenovirus receptor (CAR) on human erythrocytes. We show that the presence of CAR on erythrocytes leads to prolonged in vivo blood half-life and significantly reduced liver infection when a CAR-tropic Ad is injected intravenously. This study provides i) a molecular and structural rationale for Ad–erythrocyte interactions, ii) a basis to improve vector-mediated gene transfer and iii) a mechanism that may explain the biodistribution and pathogenic inconsistencies found between human and animal models. PMID:19119424

  20. The influence of exercise-induced oxidative stress on binding and degradation of 125I-insulin by the receptors on erythrocytes.

    PubMed

    Szcześniak, L; Karolkiewicz, J; Deskur, E; Rychlewski, T; Konys, L; Stankiewicz, K

    1998-09-01

    In the present work we investigated the influence of oxidative stress induced by strenuous exercise on the affinity of a specific insulin receptors on human erythrocytes. 13 male members of the national basketball staff performed a maximal treadmill exercise test. In the blood samples collected before and directly after the test acid-base equilibrium parameters, lactic acid concentrations, glucose and insulin serum levels as well as 125I-insulin binding and degradation by receptor on erythrocytes were measured. As markers of oxidative stress, plasma thiobarbituric acid-reactive substance levels (TBARS) and red blood cells glutathione content (GSH) were determined. After the exercise test TBARS levels increased significantly and GSH concentrations decreased indicating that oxidative stress occurred. Binding of 125I-insulin to the receptors on erythrocytes decreased significantly during the test, while there was only insignificant reduction in 125I-insulin degradation. Correlation analysis and multiple linear regression revealed that changes in insulin degradation by receptors on erythrocytes during exhaustive exercise are determined by oxidative stress, probably via oxidation of sulfhydryl groups of certain enzymes. The affinity of receptors for insulin seems to depend mainly on glucose concentrations.

  1. Influence of Plasmodium vivax malaria on the relations between the osmotic stability of human erythrocyte membrane and hematological and biochemical variables.

    PubMed

    Mascarenhas Netto, Rita de Cássia; Fabbri, Camila; de Freitas, Mariana Vaini; Bernardino Neto, Morun; Garrote-Filho, Mário Silva; Lacerda, Marcus Vinícius Guimarães; Lima, Emerson Silva; Penha-Silva, Nilson

    2014-03-01

    This study evaluated the influence of infection by Plasmodium vivax on the relations between hematological and biochemical variables and the osmotic stability of the erythrocyte membrane in a Brazilian Amazon population. A total of 72 patients with P. vivax malaria were included in the study and invited to return after 14 days, post-treatment with chloroquine and primaquine, for clinical and laboratorial reevaluations. The osmotic stability of the erythrocyte membrane was analyzed by nonlinear regression of the dependency of the absorbance of hemoglobin, released with hemolysis, as a function of the salt concentration, and it was represented by the inverse of the salt concentration at the midpoint of the curve (1/H 50) and by the variation of salt concentration, which promotes lysis (dX). Bivariate and multivariate methods were used in the analysis of the results. Prior to treatment of the disease, the erythrocytes showed greater stability, probably due to the natural selection of young and also more stable erythrocytes. The bivariate analysis showed that 1/H 50 was positively correlated with red cell distribution width (RDW), urea, triglycerides, and very low-density lipoprotein (VLDL)-cholesterol, but negatively associated with albumin, HDL-cholesterol, and indirect bilirubin, while dX was negatively associated with the mean corpuscular hemoglobin concentration. These associations were confirmed by canonical correlation analysis. Stepwise multiple linear regression showed that albumin, urea, triglycerides, and VLDL-cholesterol are the variables with the highest abilities of predicting erythrocyte stability. The bivariate analysis also showed that the hematological index RDW was related to elevated levels of bilirubin and decreased levels of albumin and urea, associated with liver damage resulting from malaria.

  2. Influence of erythrocyte oxygenation and intravascular ATP on resting and exercising skeletal muscle blood flow in humans with mitochondrial myopathy.

    PubMed

    Jeppesen, Tina D; Vissing, John; González-Alonso, José

    2012-05-01

    Oxygen (O₂) extraction is impaired in exercising skeletal muscle of humans with mutations of mitochondrial DNA (mtDNA), but the muscle hemodynamic response to exercise has never been directly investigated. This study sought to examine the extent to which human skeletal muscle perfusion can increase without reductions in blood oxygenation and to determine whether erythrocyte O₂ off-loading and related ATP vascular mechanisms are impaired in humans with mutations of mtDNA. Leg vascular hemodynamic, oxygenation and ATP were investigated in ten patients with mtDNA mutations and ten matched healthy control subjects: 1) at rest during normoxia, hypoxia, hyperoxia and intra-femoral artery ATP infusion, and 2) during passive and dynamic one-legged knee-extensor exercises. At rest, blood flow (LBF), femoral arterial and venous blood oxygenation and plasma ATP were similar in the two groups. During dynamic exercise, LBF and vascular conductance increased 9-10 fold in the patients despite erythrocyte oxygenation and leg O₂ extraction remained unchanged (p<0.01). In the patients, workload-adjusted LBF was 28% to 62% higher during submaximal- and maximal exercises and was associated with augmented plasma ATP. The appropriate hemodynamic adjustments during severe hypoxia and ATP infusion suggest that erythrocyte O₂ off-loading and related ATP vascular mechanisms are intact in patients with mtDNA mutations. Furthermore, greater increase in plasma ATP and LBF at a given metabolic demand in the patients, in concert with unchanged oxyhemoglobin, suggest that erythrocyte O₂ off-loading is not obligatory for the exercise-induced increase in blood flow and intravascular ATP concentration. PMID:22155147

  3. [INFLUENCE OF MEDICINAL PLANT EXTRACTS ON THE FUNCTIONS AND ANTIOXIDANT PROTECTION OF ERYTHROCYTES IN RATS WITH EXPERIMENTAL DIABETES MELLITUS].

    PubMed

    Vengerovskii, A I; Yakimova, T V; Nasanova, O N

    2016-01-01

    Experiments on rats with diabetes mellitus model induced by streptosotocin and high (30%) fat diet showed that the daily treatment with aqueous extracts of great nettle leaves (100 mg/kg) and common burdock roots (25 mg/kg) for a period of 10 days led to a decrease in the glycemic index and triglyceride level and produced protective action on erythrocytes both in animals kept on a fat-rich diet and on the background of a low-caloric ration. Both medicinal plant extracts were comparable with reference drug metformin in reducing the concentration of glycosylated hemoglobin (by 12-31%) and ectoglobular hemoglobin (1.7-1.8 times, p <0.05), decreasing the content of malonic dialdehyde in erythrocytes (1.3 times, p < 0.05), and increasing erythrocyte deformability (1.3-1.4 times, p < 0.05) and activity of their antioxidant enzymes glutathione peroxidase, glutathione reductase, glutathione-S-transferase, catalase, and supe- roxide dismutase (1.2-2.6 times, p < 0.05). A diet with usual (8%) fat content improved the metabolic indices to a lower degree (on the average by 13-21%, p < 0.05) than did the proposed phytotherapy. PMID:27416680

  4. [INFLUENCE OF MEDICINAL PLANT EXTRACTS ON THE FUNCTIONS AND ANTIOXIDANT PROTECTION OF ERYTHROCYTES IN RATS WITH EXPERIMENTAL DIABETES MELLITUS].

    PubMed

    Vengerovskii, A I; Yakimova, T V; Nasanova, O N

    2016-01-01

    Experiments on rats with diabetes mellitus model induced by streptosotocin and high (30%) fat diet showed that the daily treatment with aqueous extracts of great nettle leaves (100 mg/kg) and common burdock roots (25 mg/kg) for a period of 10 days led to a decrease in the glycemic index and triglyceride level and produced protective action on erythrocytes both in animals kept on a fat-rich diet and on the background of a low-caloric ration. Both medicinal plant extracts were comparable with reference drug metformin in reducing the concentration of glycosylated hemoglobin (by 12-31%) and ectoglobular hemoglobin (1.7-1.8 times, p <0.05), decreasing the content of malonic dialdehyde in erythrocytes (1.3 times, p < 0.05), and increasing erythrocyte deformability (1.3-1.4 times, p < 0.05) and activity of their antioxidant enzymes glutathione peroxidase, glutathione reductase, glutathione-S-transferase, catalase, and supe- roxide dismutase (1.2-2.6 times, p < 0.05). A diet with usual (8%) fat content improved the metabolic indices to a lower degree (on the average by 13-21%, p < 0.05) than did the proposed phytotherapy.

  5. Environmental Influences on the Behavioral Phenotype of Angelman Syndrome

    ERIC Educational Resources Information Center

    Horsler, Kate; Oliver, Chris

    2006-01-01

    Using observational methods, we examined the social influences on laughing and smiling behavior in children with Angelman syndrome by systematically manipulating aspects of social interaction. Seven boys and 4 girls who were between 4 and 11 years of age and who had a confirmed maternal deletion of chromosome 15q11-q13 completed the study. Each…

  6. Influence of age, irradiation and humanization on NSG mouse phenotypes

    PubMed Central

    Knibbe-Hollinger, Jaclyn S.; Fields, Natasha R.; Chaudoin, Tammy R; Epstein, Adrian A.; Makarov, Edward; Akhter, Sidra P.; Gorantla, Santhi; Bonasera, Stephen J.; Gendelman, Howard E.; Poluektova, Larisa Y.

    2015-01-01

    ABSTRACT Humanized mice are frequently utilized in bench to bedside therapeutic tests to combat human infectious, cancerous and degenerative diseases. For the fields of hematology-oncology, regenerative medicine, and infectious diseases, the immune deficient mice have been used commonly in basic research efforts. Obstacles in true translational efforts abound, as the relationship between mouse and human cells in disease pathogenesis and therapeutic studies requires lengthy investigations. The interplay between human immunity and mouse biology proves ever more complicated when aging, irradiation, and human immune reconstitution are considered. All can affect a range of biochemical and behavioral functions. To such ends, we show age- and irradiation-dependent influences for the development of macrocytic hyper chromic anemia, myelodysplasia, blood protein reductions and body composition changes. Humanization contributes to hematologic abnormalities. Home cage behavior revealed day and dark cycle locomotion also influenced by human cell reconstitutions. Significant age-related day-to-day variability in movement, feeding and drinking behaviors were observed. We posit that this data serves to enable researchers to better design translational studies in this rapidly emerging field of mouse humanization. PMID:26353862

  7. What monozygotic twins discordant for phenotype illustrate about mechanisms influencing genetic forms of neurodegeneration.

    PubMed

    Ketelaar, M E; Hofstra, E M W; Hayden, M R

    2012-04-01

    As monozygotic (MZ) twins are believed to be genetically identical, discordance for disease phenotype between MZ twins has been used in genetic research to understand the contribution of genetic vs environmental factors in disease development. However, recent studies show that MZ twins can differ both genetically and epigenetically. Screening MZ twins for genetic and/or epigenetic differences could be a useful and novel approach to identify modifying factors influencing phenotypic expression of disease. MZ twins that are phenotypically discordant for monogenic diseases are of special interest. Such occurrences have been described for Huntington's disease, spinocerebellar ataxias, as well as for familial forms of Alzheimer's disease. By comparing MZ twins that are phenotypically discordant, crucial factors influencing the phenotypic expression of the disease could be identified, which may be of relevance for understanding disease pathogenesis and variability in disease phenotype. Overall, understanding the crucial factors in development of a neurodegenerative disorder will have relevance for predictive testing, preventive treatment and could help to identify novel therapeutic targets. PMID:21981075

  8. Sb(V) and Sb(III) distribution in human erythrocytes: speciation methodology and the influence of temperature, time and anticoagulants.

    PubMed

    Quiroz, Waldo; Aguilar, Luis; Barría, Macarena; Veneciano, Jocelyn; Martínez, Daniel; Bravo, Manuel; Lobos, María Gabriela; Mercado, Luis

    2013-10-15

    In this research a new method was developed and optimized for the determination of Sb(V) and Sb(III) in human erythrocytes fractions (plasma and cytoplasm) by high performance liquid chromatography with hydride generation atomic fluorescence spectrometry. The method considers the first step of samples cleaning by protein precipitation by salting out followed by C18 solid phase extraction, EDTA elution, and finally a chromatographic separation by using anion exchange PRPX-100 (100 mm × 4.1mm) and EDTA 20 mmol L(-1) as mobile phase. The method was optimized by experimental design with a recovery of 90% for Sb(V) and 55-75% for Sb(III) approximately. The analytical method was applied to study the distribution of Sb(V) and Sb(III) in human erythrocytes considering temperature and time of incubations and with special attention about the influence of the anticoagulant. Results showed that both Sb(V) and Sb(III) are capable to enter the red blood cell in a proportion of approximately 40-60%. On the other hand, both species are then excreted from the interior of the cell, where the percentage considerably decreased from approximately 60 to less than 30% within the cell. An increase in the culture temperature increases the capacity of Sb(V) and Sb(III) to penetrate the membrane barrier and reach the cytoplasm. In order to preserve the original distribution of Sb in blood, heparin seems to be the best anticoagulant for sample preservation.

  9. Genetic and Environmental Influences on Neuroimaging Phenotypes: A Meta-Analytical Perspective on Twin Imaging Studies

    PubMed Central

    Blokland, Gabriella A. M.; de Zubicaray, Greig I.; McMahon, Katie L.; Wright, Margaret J.

    2014-01-01

    Because brain structure and function are affected in neurological and psychiatric disorders, it is important to disentangle the sources of variation in these phenotypes. Over the past 15 years, twin studies have found evidence for both genetic and environmental influences on neuroimaging phenotypes, but considerable variation across studies makes it difficult to draw clear conclusions about the relative magnitude of these influences. Here we performed the first meta-analysis of structural MRI data from 48 studies on >1,250 twin pairs, and diffusion tensor imaging data from 10 studies on 444 twin pairs. The proportion of total variance accounted for by genes (A), shared environment (C), and unshared environment (E), was calculated by averaging A, C, and E estimates across studies from independent twin cohorts and weighting by sample size. The results indicated that additive genetic estimates were significantly different from zero for all meta-analyzed phenotypes, with the exception of fractional anisotropy (FA) of the callosal splenium, and cortical thickness (CT) of the uncus, left parahippocampal gyrus, and insula. For many phenotypes there was also a significant influence of C. We now have good estimates of heritability for many regional and lobar CT measures, in addition to the global volumes. Confidence intervals are wide and number of individuals small for many of the other phenotypes. In conclusion, while our meta-analysis shows that imaging measures are strongly influenced by genes, and that novel phenotypes such as CT measures, FA measures, and brain activation measures look especially promising, replication across independent samples and demographic groups is necessary. PMID:22856370

  10. An acousto-optical method for registration of erythrocytes' agglutination reaction—sera color influence on the resolving power

    NASA Astrophysics Data System (ADS)

    Doubrovski, V. A.; Medvedeva, M. F.; Torbin, S. O.

    2016-01-01

    The absorption spectra of agglutinating sera were used to determine blood groups. It was shown experimentally that the sera color significantly affects the resolving power of the acousto-optical method of blood typing. In order to increase the resolving power of the method and produce an invariance of the method for sera color, we suggested introducing a probing light beam individually for different sera. The proposed technique not only improves the resolving power of the method, but also reduces the risk of false interpretation of the experimental results and, hence, error in determining the blood group of the sample. The latter is especially important for the typing of blood samples with weak agglutination of erythrocytes. This study can be used in the development of an instrument for instrumental human blood group typing based on the acousto-optical method.

  11. Bivariate and multivariate analyses of the influence of blood variables of patients submitted to Roux-en-Y gastric bypass on the stability of erythrocyte membrane against the chaotropic action of ethanol.

    PubMed

    de Arvelos, Leticia Ramos; Rocha, Vanessa Custódio Afonso; Felix, Gabriela Pereira; da Cunha, Cleine Chagas; Bernardino Neto, Morun; da Silva Garrote Filho, Mario; de Fátima Pinheiro, Conceição; Resende, Elmiro Santos; Penha-Silva, Nilson

    2013-03-01

    The stability of the erythrocyte membrane, which is essential for the maintenance of cell functions, occurs in a critical region of fluidity, which depends largely on its composition and the composition and characteristics of the medium. As the composition of the erythrocyte membrane is influenced by several blood variables, the stability of the erythrocyte membrane must have relations with them. The present study aimed to evaluate, by bivariate and multivariate statistical analyses, the correlations and causal relationships between hematologic and biochemical variables and the stability of the erythrocyte membrane against the chaotropic action of ethanol. The validity of this type of analysis depends on the homogeneity of the population and on the variability of the studied parameters, conditions that can be filled by patients who undergo bariatric surgery by the technique of Roux-en-Y gastric bypass since they will suffer feeding restrictions that have great impact on their blood composition. Pathway analysis revealed that an increase in hemoglobin leads to decreased stability of the cell, probably through a process mediated by an increase in mean corpuscular volume. Furthermore, an increase in the mean corpuscular hemoglobin (MCH) leads to an increase in erythrocyte membrane stability, probably because higher values of MCH are associated with smaller quantities of red blood cells and a larger contact area between the cell membrane and ethanol present in the medium.

  12. Phenotypic and genotypic convergences are influenced by historical contingency and environment in yeast

    PubMed Central

    NIDELET, Thibault; MARTIN, Juliette; LEGRAND, Judith; DILLMANN, Christine; BOURGAIS, Aurélie; de VIENNE, Dominique; SHERLOCK, Gavin; SICARD, Delphine

    2015-01-01

    Different organisms have independently and recurrently evolved similar phenotypic traits at different points throughout history. This phenotypic convergence may be caused by genotypic convergence and constrained by historical contingency. To investigate how convergence may be driven by selection in a particular environment and constrained by history, we analyzed nine life-history traits and four metabolic traits during an experimental evolution of six yeast strains in four different environments. In each of the environments, the population converged towards a different life-history strategy. However, phenotypic convergence was partly associated with the selection of mutations in genes involved in the same pathway. In a fifth of our evolution experiments, mutations in the same gene, BMH1, were selected, in three out of the six ancestral genotypes. Two types of BMH1 mutation with opposite phenotypic effects on several traits were found. The evolution of most traits, as well as the occurrence of BMH1 mutations, was significantly influenced by the ancestral strain. However, this effect could not be easily predicted from ancestors’ phylogeny or past-selection. All together, our data demonstrate that phenotypic and its underlying genotypic convergence depends on a complex interplay between the evolutionary environment, pleiotropy and the ancestor genetic background but are not straightforwardly predicable. PMID:24164389

  13. Erythrocyte rouleau formation under polarized electromagnetic fields

    NASA Astrophysics Data System (ADS)

    Sebastián, José Luis; San Martín, Sagrario Muñoz; Sancho, Miguel; Miranda, José Miguel; Álvarez, Gabriel

    2005-09-01

    We study the influence of an external electromagnetic field of 1.8GHz in the formation or disaggregation of long rouleau of identical erythrocyte cells. In particular we calculate the variation of the transmembrane potential of an individual erythrocyte illuminated by the external field due to the presence of the neighboring erythrocytes in the rouleau, and compare the total electric energy of isolated cells with the total electric energy of the rouleau. We show that the polarization of the external electromagnetic field plays a fundamental role in the total energy variation of the cell system, and consequently in the formation or disaggregation of rouleau.

  14. Erythrocytic Iron Deficiency Enhances Susceptibility to Plasmodium chabaudi Infection in Mice Carrying a Missense Mutation in Transferrin Receptor 1

    PubMed Central

    Lelliott, Patrick M.; McMorran, Brendan J.; Foote, Simon J.

    2015-01-01

    The treatment of iron deficiency in areas of high malaria transmission is complicated by evidence which suggests that iron deficiency anemia protects against malaria, while iron supplementation increases malaria risk. Iron deficiency anemia results in an array of pathologies, including reduced systemic iron bioavailability and abnormal erythrocyte physiology; however, the mechanisms by which these pathologies influence malaria infection are not well defined. In the present study, the response to malaria infection was examined in a mutant mouse line, TfrcMRI24910, identified during an N-ethyl-N-nitrosourea (ENU) screen. This line carries a missense mutation in the gene for transferrin receptor 1 (TFR1). Heterozygous mice exhibited reduced erythrocyte volume and density, a phenotype consistent with dietary iron deficiency anemia. However, unlike the case in dietary deficiency, the erythrocyte half-life, mean corpuscular hemoglobin concentration, and intraerythrocytic ferritin content were unchanged. Systemic iron bioavailability was also unchanged, indicating that this mutation results in erythrocytic iron deficiency without significantly altering overall iron homeostasis. When infected with the rodent malaria parasite Plasmodium chabaudi adami, mice displayed increased parasitemia and succumbed to infection more quickly than their wild-type littermates. Transfusion of fluorescently labeled erythrocytes into malaria parasite-infected mice demonstrated an erythrocyte-autonomous enhanced survival of parasites within mutant erythrocytes. Together, these results indicate that TFR1 deficiency alters erythrocyte physiology in a way that is similar to dietary iron deficiency anemia, albeit to a lesser degree, and that this promotes intraerythrocytic parasite survival and an increased susceptibility to malaria in mice. These findings may have implications for the management of iron deficiency in the context of malaria. PMID:26303393

  15. Erythrocytic Iron Deficiency Enhances Susceptibility to Plasmodium chabaudi Infection in Mice Carrying a Missense Mutation in Transferrin Receptor 1.

    PubMed

    Lelliott, Patrick M; McMorran, Brendan J; Foote, Simon J; Burgio, Gaetan

    2015-11-01

    The treatment of iron deficiency in areas of high malaria transmission is complicated by evidence which suggests that iron deficiency anemia protects against malaria, while iron supplementation increases malaria risk. Iron deficiency anemia results in an array of pathologies, including reduced systemic iron bioavailability and abnormal erythrocyte physiology; however, the mechanisms by which these pathologies influence malaria infection are not well defined. In the present study, the response to malaria infection was examined in a mutant mouse line, Tfrc(MRI24910), identified during an N-ethyl-N-nitrosourea (ENU) screen. This line carries a missense mutation in the gene for transferrin receptor 1 (TFR1). Heterozygous mice exhibited reduced erythrocyte volume and density, a phenotype consistent with dietary iron deficiency anemia. However, unlike the case in dietary deficiency, the erythrocyte half-life, mean corpuscular hemoglobin concentration, and intraerythrocytic ferritin content were unchanged. Systemic iron bioavailability was also unchanged, indicating that this mutation results in erythrocytic iron deficiency without significantly altering overall iron homeostasis. When infected with the rodent malaria parasite Plasmodium chabaudi adami, mice displayed increased parasitemia and succumbed to infection more quickly than their wild-type littermates. Transfusion of fluorescently labeled erythrocytes into malaria parasite-infected mice demonstrated an erythrocyte-autonomous enhanced survival of parasites within mutant erythrocytes. Together, these results indicate that TFR1 deficiency alters erythrocyte physiology in a way that is similar to dietary iron deficiency anemia, albeit to a lesser degree, and that this promotes intraerythrocytic parasite survival and an increased susceptibility to malaria in mice. These findings may have implications for the management of iron deficiency in the context of malaria.

  16. Inositol phosphates influence the membrane bound Ca/sup 2 +//Mg/sup 2 +/ stimulated ATPase from human erythrocyte membranes

    SciTech Connect

    Kester, M.; Ekholm, J.; Kumar, R.; Hanahan, D.J.

    1986-03-01

    The modulation by exogenous inositol phosphates of the membrane Ca/sup 2 +//Mg/sup 2 +/ ATPase from saponin/EGTA lysed human erythrocytes was determined in a buffer (pH 7.6) containing histidine, 80 mM, MgCl/sub 2/, 3.3 mM, NaCl, 74 mM, KCl, 30 mM, Na/sub 2/ATP, 2.3 mM, ouabain, 0.83 mM, with variable amounts of CaCl/sub 2/ and EGTA. The ATPase assay was linear with time at 44/sup 0/C. The inositol phosphates were commercially obtained and were also prepared from /sup 32/P labeled rabbit platelet inositol phospholipids. Inositol triphosphate (IP/sub 3/) elevated the Ca/sup 2 +//Mg/sup 2 +/ ATPase activity over basal levels in a dose, time, and calcium dependent manner and were increased up to 85% of control values. Activities for the Na/sup +//K/sup +/-ATPase and a Mg/sup 2 +/ ATPase were not effected by IP/sub 3/. Ca/sup 2 +//Mg/sup 2 +/APTase activity with IP/sub 2/ or IP/sub 3/ could be synergistically elevated with calmodulin addition. The activation of the ATPase with IP/sub 3/ was calcium dependent in a range from .001 to .02 mM. The apparent Km and Vmax values were determined for IP/sub 3/ stimulated Ca/sup 2 +//Mg/sup 2 +/ ATPase.

  17. Levels of text comprehension in children with autism spectrum disorders (ASD): the influence of language phenotype.

    PubMed

    Lucas, Rebecca; Norbury, Courtenay Frazier

    2014-11-01

    Many children with autism spectrum disorders (ASD) have reading comprehension difficulties, but the level of processing at which comprehension is most vulnerable and the influence of language phenotype on comprehension skill is currently unclear. We explored comprehension at sentence and passage levels across language phenotypes. Children with ASD and age-appropriate language skills (n = 25) demonstrated similar syntactic and semantic facilitation to typically developing peers. In contrast, few children with ASD and language impairments (n = 25) could read beyond the single word level. Those who could read sentences benefited from semantic coherence, but were less sensitive to syntactic coherence. At the passage level, the strongest predictor of comprehension was vocabulary knowledge. This emphasizes that the intimate relationship between language competence and both decoding skill and comprehension is evident at the sentence, as well as the passage level, for children with ASD.

  18. Human erythrocyte antigens. Regulation of expression of a novel erythrocyte surface antigen by the inhibitor Lutheran In(Lu) gene.

    PubMed Central

    Telen, M J; Eisenbarth, G S; Haynes, B F

    1983-01-01

    Our study describes a novel human erythrocyte protein antigen, the expression of which is regulated by the rare Lutheran inhibitor In(Lu) gene. We have produced a monoclonal antibody (A3D8) that bound strongly to erythrocytes from subjects with Lutheran phenotypes Lu(a+b+), Lu(a+b-), and Lu(a-b+) but bound negligibly to erythrocytes from subjects with the dominant form of Lu(a-b-) phenotype, reflecting inheritance of the In(Lu) gene. Importantly, erythrocytes from an individual with the recessive form of Lu(a-b-) phenotype (i.e., absence of the In(Lu) gene and absence of genes encoding for Lutheran antigens) showed reactivity with A3D8 antibody comparable to that seen with Lu(a+) or Lu(b+) erythrocytes. A3D8 antigen activity was also found on all leukocytes and in serum and plasma; this activity also appeared to be regulated by the In(Lu) gene in serum, plasma, and on a subset of leukocytes. Thus, we have identified a human erythrocyte protein whose expression is modified by the In(Lu) gene. This knowledge that such an antigen exists on erythrocytes and in normal plasma should allow further studies into the molecular genetics of the In(Lu) gene and into the functional and structural significance of the A3D8 antigen. PMID:6863545

  19. Profiling the repertoire of phenotypes influenced by environmental cues that occur during asexual reproduction

    PubMed Central

    Dombrovsky, Aviv; Arthaud, Laury; Ledger, Terence N.; Tares, Sophie; Robichon, Alain

    2009-01-01

    The aphid Acyrthosiphon pisum population is composed of different morphs, such as winged and wingless parthenogens, males, and sexual females. The combined effect of reduced photoperiodicity and cold in fall triggers the apparition of sexual morphs. In contrast they reproduce asexually in spring and summer. In our current study, we provide evidence that clonal individuals display phenotypic variability within asexual morph categories. We describe that clones sharing the same morphological features, which arose from the same founder mother, constitute a repertoire of variants with distinct behavioral and physiological traits. Our results suggest that the prevailing environmental conditions influence the recruitment of adaptive phenotypes from a cohort of clonal individuals exhibiting considerable molecular diversity. However, we observed that the variability might be reduced or enhanced by external factors, but is never abolished in accordance with a model of stochastically produced phenotypes. This overall mechanism allows the renewal of colonies from a few adapted individuals that survive drastic episodic changes in a fluctuating environment. PMID:19635846

  20. Influence of temperature on reproductive biology and phenotype of a ladybird, Menochilus sexmaculatus (Fabricius) (Coleoptera: Coccinellidae).

    PubMed

    Dubey, A; Omkar; Mishra, G

    2016-05-01

    Body melanisation in insects is polygenic, resulting from genetic polymorphism or phenotypic plasticity, with diverse implications ranging from thermal budgeting to reproductive success. In this study, we assessed the, mate choice, reproductive success, and offspring colouration of typical (T) and melanic (M) morphs of the ladybird Menochilus sexmaculatus paired at three temperatures 15°C, 25°C and 35°C. Mating success of the two morphs and the consequences for offspring fitness and offspring phenotype under these temperature regimes were evaluated. Melanic adults of both sexes achieved significantly higher mating success at 15°C and 25°C, but at 35°C no influence of adult morph on mate selection was observed. Melanic females were more fecund than typical females at all temperatures. Offspring of melanic parents developed faster than those of typicals at 15°C and 25°C, but not at 35°C. Evidence was also found of phenotypic plasticity in colour form at 15°C and 35°C. At 25°C the parents of pure (T) and (M) morphs produced offspring of the same morph. However, low temperature induced partial melanisation among the offspring of typical parents (T). Whereas at 35°C the offspring of (T) parents became paler in colour with very fine zigzag lines on elytra, i.e. they decrease the degree of melanisation. Pure melanics (M) compensated for elevated temperature stress by producing offspring that were either pure melanic but small or large with reduced melanisation. Our results on offspring phenotype variation indicate that the degree of melanism in morphs is a result of environmentally regulated expression of the parental genotype. PMID:27157332

  1. Combined influences of Gm and HLA phenotypes upon multiple sclerosis susceptibility and severity.

    PubMed Central

    Salier, J P; Sesboüé, R; Martin-Mondière, C; Daveau, M; Cesaro, P; Cavelier, B; Coquerel, A; Legrand, L; Goust, J M; Degos, J D

    1986-01-01

    In some Caucasian populations, multiple sclerosis (MS) susceptibility has been independently related to given alleles of HLA or Gm systems that respectively code for major histocompatibility complex class I and II antigens or immunoglobulin G heavy chains. Whether given combinations of alleles at both series of loci simultaneously influence MS susceptibility and/or severity was investigated by comparing 147 French MS patients and 226 geographically-matched healthy controls. The G2m(-23)/HLA-B35 phenotype and G1m(-1)/HLA-B7(-)/HLA-DR2 phenotype were respectively associated with significant protection against (relative risk = 0.05) and susceptibility to (relative risk = 4.3) MS. When considering MS severity, the presence of HLA-B7 antigen correlated with a more severe disease in Gm1/Gm3 heterozygous patients, but not in Gm3/Gm3 homozygous patients. Conversely, an HLA-B12-associated milder disease was restricted to Gm3/Gm3 homozygotes. These results demonstrate the combined influence on MS of genetic loci that are unlinked but immune response-associated. Combined Gm and HLA typing is very likely able to serve as a prognostic indicator in this disease. PMID:3461005

  2. Combined influences of Gm and HLA phenotypes upon multiple sclerosis susceptibility and severity.

    PubMed

    Salier, J P; Sesboüé, R; Martin-Mondière, C; Daveau, M; Cesaro, P; Cavelier, B; Coquerel, A; Legrand, L; Goust, J M; Degos, J D

    1986-08-01

    In some Caucasian populations, multiple sclerosis (MS) susceptibility has been independently related to given alleles of HLA or Gm systems that respectively code for major histocompatibility complex class I and II antigens or immunoglobulin G heavy chains. Whether given combinations of alleles at both series of loci simultaneously influence MS susceptibility and/or severity was investigated by comparing 147 French MS patients and 226 geographically-matched healthy controls. The G2m(-23)/HLA-B35 phenotype and G1m(-1)/HLA-B7(-)/HLA-DR2 phenotype were respectively associated with significant protection against (relative risk = 0.05) and susceptibility to (relative risk = 4.3) MS. When considering MS severity, the presence of HLA-B7 antigen correlated with a more severe disease in Gm1/Gm3 heterozygous patients, but not in Gm3/Gm3 homozygous patients. Conversely, an HLA-B12-associated milder disease was restricted to Gm3/Gm3 homozygotes. These results demonstrate the combined influence on MS of genetic loci that are unlinked but immune response-associated. Combined Gm and HLA typing is very likely able to serve as a prognostic indicator in this disease. PMID:3461005

  3. Genetic variation in BEACON influences quantitative variation in metabolic syndrome-related phenotypes.

    PubMed

    Jowett, Jeremy B; Elliott, Kate S; Curran, Joanne E; Hunt, Nicola; Walder, Ken R; Collier, Greg R; Zimmet, Paul Z; Blangero, John

    2004-09-01

    The BEACON gene (also known as UBL5) was identified as differentially expressed between lean and obese Psammomys obesus, a polygenic animal model of obesity, type 2 diabetes, and dyslipidemia. The human homologue of BEACON is located on chromosome 19p, a region likely to contain genes affecting metabolic syndrome-related quantitative traits as established by linkage studies. To assess whether the human BEACON gene may be involved in influencing these traits, we exhaustively analyzed the complete gene for genetic variation in 40 unrelated individuals and identified four variants (three novel). The two more common variants were tested for association with a number of quantitative metabolic syndrome-related traits in two large cohorts of unrelated individuals. Significant associations were found between these variants and fat mass (P = 0.026), percentage of fat (P = 0.001), and waist-to-hip ratio (P = 0.031). The same variants were also associated with total cholesterol (P = 0.024), LDL cholesterol (P = 0.019), triglycerides (P = 0.006), and postglucose load insulin levels (P = 0.018). Multivariate analysis of these correlated phenotypes also yielded a highly significant association (P = 0.0004), suggesting that BEACON may influence phenotypic variation in metabolic syndrome-related traits.

  4. [Kinetics of Cu crossing human erythrocyte membrane].

    PubMed

    Dun, Zhu Ci Ren

    2014-12-01

    This study was aimed to investigate various factors influencing the proceduction of Cu(II) crossing human erythrocyte membrane, including concentration of Cu²⁺, pH value of the medium, temperature and time of incubation, and to derive kinetic equation of Cu(II) crossing human erythrocyte membrane. Suspension red blood cells were incubated by Cu²⁺, then content of Cu²⁺ crossed human erythrocyte membrane was determined by atomic absorption spectrometry under various conditions after digestion. The results showed that content of Cu²⁺ crossed human erythrocyte membrane increased with the increase of extracellular Cu²⁺ and enhancement of incubation temperature, and the content of Cu²⁺ crossed human erythrocyte membrane showed a increasing tendency when pH reached to 6.2-7.4, and to maximum at pH 7.4, then gradually decreased at range of pH 7.4-9.2. It is concluded that the Cu²⁺ crossing human erythrocyte has been confirmed to be the first order kinetics characteristics within 120 min, and the linear equation is 10³ × Y = 0.0497t +6.5992.

  5. Induction of Suicidal Erythrocyte Death by Nelfinavir

    PubMed Central

    Bissinger, Rosi; Waibel, Sabrina; Lang, Florian

    2015-01-01

    The HIV protease inhibitor, nelfinavir, primarily used for the treatment of HIV infections, has later been shown to be effective in various infectious diseases including malaria. Nelfinavir may trigger mitochondria-independent cell death. Erythrocytes may undergo eryptosis, a mitochondria-independent suicidal cell death characterized by cell shrinkage and phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include oxidative stress and increase of cytosolic Ca2+-activity ([Ca2+]i). During malaria, accelerated death of infected erythrocytes may decrease parasitemia and thus favorably influence the clinical course of the disease. In the present study, phosphatidylserine abundance at the cell surface was estimated from annexin V binding, cell volume from forward scatter, reactive oxidant species (ROS) from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence, and [Ca2+]i from Fluo3-fluorescence. A 48 h treatment of human erythrocytes with nelfinavir significantly increased the percentage of annexin-V-binding cells (≥5µg/mL), significantly decreased forward scatter (≥2.5µg/mL), significantly increased ROS abundance (10 µg/mL), and significantly increased [Ca2+]i (≥5 µg/mL). The up-regulation of annexin-V-binding following nelfinavir treatment was significantly blunted, but not abolished by either addition of the antioxidant N-acetylcysteine (1 mM) or removal of extracellular Ca2+. In conclusion, exposure of erythrocytes to nelfinavir induces oxidative stress and Ca2+ entry, thus leading to suicidal erythrocyte death characterized by erythrocyte shrinkage and erythrocyte membrane scrambling. PMID:26008229

  6. Influence of environmental factors on the expression of phenotypic characters by chicken dorsal root ganglion cells in culture.

    PubMed

    Barakat, I; Droz, B

    1985-01-01

    Primary sensory neurons were grown under four conditions of culture. The influence of nonneuronal cells, horse serum or both was studied on the phenotypic expression of certain neuronal subpopulations. The number of neurons expressing acetylcholinesterase, alpha-bungarotoxin-binding sites or a high uptake capacity for glutamine was enhanced by nonneuronal cells. The horse serum increases the neuronal subpopulation exhibiting a carbonic anhydrase activity. Certain phenotypic changes fit conditions consistent with an epigenetic induction rather than a cell selection.

  7. IFN‐λ3 polymorphism indirectly influences NK cell phenotype and function during acute HCV infection

    PubMed Central

    Depla, Marion; Pelletier, Sandy; Bédard, Nathalie; Brunaud, Camille; Bruneau, Julie

    2016-01-01

    Abstract Introduction Polymorphisms in the type III interferon IFN‐λ3 and the killer cell immunoglobulin‐like receptor (KIR) genes controlling the activity of natural killer (NK) cells can predict spontaneous resolution of acute hepatitis C virus (HCV) infection. We hypothesized that IFN‐λ3 polymorphism may modulate NK cell function during acute HCV. Methods We monitored the plasma levels of type III IFNs in relation to the phenotype and the function of NK cells in a cohort of people who inject drugs (PWID) during acute HCV infection with different outcomes. Results Early acute HCV was associated with high variability in type III IFNs plasma levels and the favorable IFN‐λ3 CC genotype was associated with higher viral loads. Reduced expression of Natural Killer Group Protein 2A (NKG2A) was associated with lower IFN‐λ3 plasma levels and the CC genotype. IFN‐γ production by NK cells was higher in individuals with the CC genotype during acute infection but this did not prevent viral persistence. IFN‐λ3 plasma levels did not correlate with function of NK cells and IFN‐λ3 prestimulation did not affect NK cell activation and function. Conclusions These results suggest that IFN‐λ3 polymorphism indirectly influences NK cell phenotype and function during acute HCV but other factors may act in concert to determine the outcome of the infection. PMID:27621819

  8. IFN‐λ3 polymorphism indirectly influences NK cell phenotype and function during acute HCV infection

    PubMed Central

    Depla, Marion; Pelletier, Sandy; Bédard, Nathalie; Brunaud, Camille; Bruneau, Julie

    2016-01-01

    Abstract Introduction Polymorphisms in the type III interferon IFN‐λ3 and the killer cell immunoglobulin‐like receptor (KIR) genes controlling the activity of natural killer (NK) cells can predict spontaneous resolution of acute hepatitis C virus (HCV) infection. We hypothesized that IFN‐λ3 polymorphism may modulate NK cell function during acute HCV. Methods We monitored the plasma levels of type III IFNs in relation to the phenotype and the function of NK cells in a cohort of people who inject drugs (PWID) during acute HCV infection with different outcomes. Results Early acute HCV was associated with high variability in type III IFNs plasma levels and the favorable IFN‐λ3 CC genotype was associated with higher viral loads. Reduced expression of Natural Killer Group Protein 2A (NKG2A) was associated with lower IFN‐λ3 plasma levels and the CC genotype. IFN‐γ production by NK cells was higher in individuals with the CC genotype during acute infection but this did not prevent viral persistence. IFN‐λ3 plasma levels did not correlate with function of NK cells and IFN‐λ3 prestimulation did not affect NK cell activation and function. Conclusions These results suggest that IFN‐λ3 polymorphism indirectly influences NK cell phenotype and function during acute HCV but other factors may act in concert to determine the outcome of the infection.

  9. Does the liposuction method influence the phenotypic characteristic of human adipose-derived stem cells?

    PubMed Central

    Bajek, Anna; Gurtowska, Natalia; Gackowska, Lidia; Kubiszewska, Izabela; Bodnar, Magdalena; Marszałek, Andrzej; Januszewski, Rafał; Michalkiewicz, Jacek; Drewa, Tomasz

    2015-01-01

    Adipose-derived stem cells (ASCs) possess a high differentiation and proliferation potential. However, the phenotypic characterization of ASCs is still difficult. Until now, there is no extensive analysis of ASCs markers depending on different liposuction methods. Therefore, the aim of the present study was to analyse 242 surface markers and determine the differences in the phenotypic pattern between ASCs obtained during mechanical and ultrasound-assisted liposuction. ASCs were isolated from healthy donors, due to mechanical and ultrasound-assisted liposuction and cultured in standard medium to the second passage. Differentiation potential and markers expression was evaluated to confirm the mesenchymal nature of cells. Then, the BD LyoplateTM Human Cell Surface Marker Screening Panel was used. Results shown that both population of ASCs are characterized by high expression of markers specific for ASCs: cluster of differentiation (CD)9, CD10, CD34, CD44, CD49d, CD54, CD55, CD59, CD71 and low expression of CD11a, CD11c and CD144. Moreover, we have noticed significant differences in antigen expression in 58 markers from the 242 studied. Presented study shows for the first time that different liposuction methods are not a significant factor which can influence the expression of human ASCs surface markers. PMID:26182374

  10. Leveraging the withered tail tip phenotype in C. elegans to identify proteins that influence membrane properties

    PubMed Central

    Svensk, Emma; Biermann, Jana; Hammarsten, Sofia; Magnusson, Fredrik; Pilon, Marc

    2016-01-01

    ABSTRACT The properties of cellular membranes are critical for most cellular functions and are influenced by several parameters including phospholipid composition, integral and peripheral membrane proteins, and environmental conditions such as temperature. We previously showed that the C. elegans paqr-2 and iglr-2 mutants have a defect in membrane homeostasis and exhibit several distinct phenotypes, including a characteristic tail tip defect and cold intolerance. In the present study we report that screening for novel mutants with these 2 defects can lead to the identification of genes that are important contributors to membrane properties. In particular we isolated 3 novel alleles of sma-1, the C. elegans homolog of βH spectrin, and 2 novel alleles of dpy-23, which encodes the C. elegans homolog of the AP2 μ subunit. We also show that sma-1 and dpy-23 act on membrane properties in pathways distinct from that of paqr-2 and iglr-2. PMID:27695656

  11. The contribution of genetic and environmental factors to quantitative variability of erythrocyte membrane proteins in primary hypotension.

    PubMed

    Ivanov, V P; Polonikov, A V; Solodilova, M A

    2005-01-01

    Our previous studies have shown that, compared with healthy individuals, patients with primary arterial hypotension (PAH) have significant quantitative changes in erythrocyte membrane proteins. The purpose of the present study was to evaluate the contribution made by genetic and environmental factors to quantitative variation of erythrocyte membrane proteins in PAH. We studied 109 hypotensive patients, 124 normotensive subjects, 222 of their first-degree relatives and 24 twin pairs by sodium dodecyl sulphate (SDS) polyacrylamide gel electrophoresis. The decomposition of total phenotypic variance of erythrocyte membrane proteins to genetic and environmental components was performed on the basis of correlations among first-degree relatives by the least squares method. The genetic dominance and shared environmental factors were found to influence the variability of cytoskeletal membrane proteins whose contents were changed in PAH. Furthermore, variations in alpha-spectrin, actin and anion exchanger in hypotensives were substantially influenced by major gene and maternal effects. Ankyrin 2.1 and actin content was under the control of common underlying genes. Variations in membrane-associated glutathione-S-transferase and tropomyosin were predominantly affected by polygenes. These findings suggest that the putative major genes with pleiotropic effects appear to be involved in the control of quantitative disorders of erythrocyte membrane proteins in primary hypotension. PMID:15638825

  12. Abnormalities in the glycosphingolipid content of human Pk and p erythrocytes.

    PubMed Central

    Marcus, D M; Naiki, M; Kundu, S K

    1976-01-01

    Erythrocytes of the rare Pk phenotype lack the blood group P antigen, and p erythrocytes lack both P and Pk antigens. On the basis of immunological data we suggested previously that the P and Pk antigens are the glycosphingolipids globoside and trihexosyl ceramide, respectively, and we have now confirmed these designations by chemical analysis of erythrocytes lacking these antigens. The Pk erythrocytes contain only traces of globoside and have a marked excess of trihexosyl ceramide in comparison with normal erythrocytes. The p erythrocytes lack globoside and trihexosyl ceramide and contain an excess of lactosyl ceramide and other complex glycolipids. Our analyses of normal erythrocytes also revealed complex gangliosides with the approximate chromatographic mobilities of GD1b and GT1, and several gangliosides containing N-acetylglucosamine. Images PMID:1067617

  13. Genetic background influences murine prostate gene expression: implications for cancer phenotypes

    PubMed Central

    Bianchi-Frias, Daniella; Pritchard, Colin; Mecham, Brigham H; Coleman, Ilsa M; Nelson, Peter S

    2007-01-01

    Background Cancer of the prostate is influenced by both genetic predisposition and environmental factors. The identification of genes capable of modulating cancer development has the potential to unravel disease heterogeneity and aid diagnostic and prevention strategies. To this end, mouse models have been developed to isolate the influences of individual genetic lesions in the context of consistent genotypes and environmental exposures. However, the normal prostatic phenotypic variability dictated by a genetic background that is potentially capable of influencing the process of carcinogenesis has not been established. Results In this study we used microarray analysis to quantify transcript levels in the prostates of five commonly studied inbred mouse strains. We applied a multiclass response t-test and determined that approximately 13% (932 genes) exhibited differential expression (range 1.3-190-fold) in any one strain relative to other strains (false discovery rate ≤10%). Expression differences were confirmed by quantitative RT-PCR, or immunohistochemistry for several genes previously shown to influence cancer progression, such as Psca, Mmp7, and Clusterin. Analyses of human prostate transcripts orthologous to variable murine prostate genes identified differences in gene expression in benign epithelium that correlated with the differentiation state of adjacent tumors. For example, the gene encoding apolipoprotein D, which is known to enhance resistance to cell stress, was expressed at significantly greater levels in benign epithelium associated with high-grade versus low-grade cancers. Conclusion These studies support the concept that the cellular, tissue, and organismal context contribute to oncogenesis and suggest that a predisposition to a sequence of events leading to pathology may exist prior to cancer initiation. PMID:17577413

  14. Subadult experience influences adult mate choice in an arthropod: exposed female wolf spiders prefer males of a familiar phenotype.

    PubMed

    Hebets, Eileen A

    2003-11-11

    Current sexual selection theory proposes several potential mechanisms driving the evolution of female mating preferences, few of which involve social interactions. Although vertebrate examples of socially influenced mating preferences do exist, the invertebrate examples are virtually nonexistent. Here I demonstrate that the mating preferences of female wolf spiders can be acquired through exposure as subadults to unrelated, sexually active adult males. I first conducted exposure trials during which subadult females of the wolf spider Schizocosa uetzi were allowed to interact with mature males of an experimentally manipulated phenotype (either black or brown forelegs). After maturation, these previously exposed females were paired with a male of either a familiar or unfamiliar manipulated phenotype for mate-choice trials. Subadult females that were exposed to directed courtship by mature males of a particular morphological phenotype were subsequently more likely to mate with a male of a familiar phenotype as adults. Furthermore, females that were exposed as subadults were more likely, as adults, to cannibalize a courting male with an unfamiliar phenotype. Unexposed females did not distinguish between phenotypes in either mate choice or cannibalism frequency. These results suggest a previously uncharacterized mechanism influencing the origin of female mating preferences and ultimately the evolution of male traits: subadult experience. This study also stresses the potential importance of learning and memory on adult mate choice in an arthropod.

  15. Subadult experience influences adult mate choice in an arthropod: Exposed female wolf spiders prefer males of a familiar phenotype

    PubMed Central

    Hebets, Eileen A.

    2003-01-01

    Current sexual selection theory proposes several potential mechanisms driving the evolution of female mating preferences, few of which involve social interactions. Although vertebrate examples of socially influenced mating preferences do exist, the invertebrate examples are virtually nonexistent. Here I demonstrate that the mating preferences of female wolf spiders can be acquired through exposure as subadults to unrelated, sexually active adult males. I first conducted exposure trials during which subadult females of the wolf spider Schizocosa uetzi were allowed to interact with mature males of an experimentally manipulated phenotype (either black or brown forelegs). After maturation, these previously exposed females were paired with a male of either a familiar or unfamiliar manipulated phenotype for mate-choice trials. Subadult females that were exposed to directed courtship by mature males of a particular morphological phenotype were subsequently more likely to mate with a male of a familiar phenotype as adults. Furthermore, females that were exposed as subadults were more likely, as adults, to cannibalize a courting male with an unfamiliar phenotype. Unexposed females did not distinguish between phenotypes in either mate choice or cannibalism frequency. These results suggest a previously uncharacterized mechanism influencing the origin of female mating preferences and ultimately the evolution of male traits: subadult experience. This study also stresses the potential importance of learning and memory on adult mate choice in an arthropod. PMID:14597702

  16. The Family Context of Autism Spectrum Disorders: Influence on the Behavioral Phenotype and Quality of Life

    PubMed Central

    Smith, Leann E.; Greenberg, Jan; Mailick, Marsha R.

    2013-01-01

    Synopsis In this review, we report the findings from our longitudinal program of research examining the bidirectional influences of the family environment on the behavioral phenotype of autism, and describe a newly developed family psychoeducation program, titled Transitioning Together, designed to reduce family stress, address behavior problems, and improve the overall quality of life of adolescents with autism and their families. In our search for characteristics of the family environment that influence the behavioral phenotype of adolescents and adults with autism, we focus on both positive dimensions of family life, such as warmth and positive remarks that may promote adaptive behavior in individuals with autism, as well as negative dimensions, such as high levels of criticism that may result in an escalation of behavior problems. We find that high levels of maternal warmth and positive remarks are associated with the abatement of behavior problems over time, while high levels of maternal criticism are associated with increasing levels of behavior problems in adolescents and adults with autism. These patterns of relationships have been replicated in a longitudinal study of families of children and adolescents with fragile X syndrome, and are consistent with other studies examining the impact of the family on the behavior of children with developmental disabilities. These findings suggest that the family environment is an important target for interventions not only to reduce family stress but also to improve the behavioral functioning of children, adolescents or adults with ASD. Building upon a well-developed intervention for families of individuals with psychiatric conditions, we report on the development of Transitioning Together, a psychoeducation program targeted to families with adolescents with autism who are approaching high school exit, a difficult transition stage for individuals with autism that is often marked by negative changes in behavior problems

  17. Nanotopographic Substrates of Poly (Methyl Methacrylate) Do Not Strongly Influence the Osteogenic Phenotype of Mesenchymal Stem Cells In Vitro

    PubMed Central

    Janson, Isaac A.; Kong, Yen P.; Putnam, Andrew J.

    2014-01-01

    The chemical, mechanical, and topographical features of the extracellular matrix (ECM) have all been documented to influence cell adhesion, gene expression, migration, proliferation, and differentiation. Topography plays a key role in the architecture and functionality of various tissues in vivo, thus raising the possibility that topographic cues can be instructive when incorporated into biomaterials for regenerative applications. In the literature, there are discrepancies regarding the potential roles of nanotopography to enhance the osteogenic phenotype of mesenchymal stem cells (MSC). In this study, we used thin film substrates of poly(methyl methacrylate) (PMMA) with nanoscale gratings to investigate the influence of nanotopography on the osteogenic phenotype of MSCs, focusing in particular on their ability to produce mineral similar to native bone. Topography influenced focal adhesion size and MSC alignment, and enhanced MSC proliferation after 14 days of culture. However, the osteogenic phenotype was minimally influenced by surface topography. Specifically, alkaline phosphatase (ALP) expression was not increased on nanotopographic films, nor was calcium deposition improved after 21 days in culture. Ca: P ratios were similar to native mouse bone on films with gratings of 415 nm width and 200 nm depth (G415) and 303 nm width and 190 nm depth (G303). Notably, all surfaces had Ca∶P ratios significantly lower than G415 films. Collectively, these data suggest that, PMMA films with nanogratings are poor drivers of an osteogenic phenotype. PMID:24594848

  18. The Relative Influence of Competition and Prey Defenses on the Phenotypic Structure of Insectivorous Bat Ensembles in Southern Africa

    PubMed Central

    Schoeman, M. Corrie; Jacobs, David S.

    2008-01-01

    Deterministic filters such as competition and prey defences should have a strong influence on the community structure of animals such as insectivorous bats that have life histories characterized by low fecundity, low predation risk, long life expectancy, and stable populations. We investigated the relative influence of these two deterministic filters on the phenotypic structure of insectivorous bat ensembles in southern Africa. We used null models to simulate the random phenotypic patterns expected in the absence of competition or prey defences and analysed the deviations of the observed phenotypic pattern from these expected random patterns. The phenotypic structure at local scales exhibited non-random patterns consistent with both competition and prey defense hypotheses. There was evidence that competition influenced body size distribution across ensembles. Competition also influenced wing and echolocation patterns in ensembles and in functional foraging groups with high species richness or abundance. At the same time, prey defense filters influenced echolocation patterns in two species-poor ensembles. Non-random patterns remained evident even after we removed the influence of body size from wing morphology and echolocation parameters taking phylogeny into account. However, abiotic filters such as geographic distribution ranges of small and large-bodied species, extinction risk, and the physics of flight and sound probably also interacted with biotic filters at local and/or regional scales to influence the community structure of sympatric bats in southern Africa. Future studies should investigate alternative parameters that define bat community structure such as diet and abundance to better determine the influence of competition and prey defences on the structure of insectivorous bat ensembles in southern Africa. PMID:19005563

  19. Influence of apoE content on receptor binding of large, bouyant LDL in subjects with different LDL subclass phenotypes.

    PubMed

    Barbagallo, C M; Levine, G A; Blanche, P J; Ishida, B Y; Krauss, R M

    1998-03-01

    We investigated the influence of apolipoprotein (apo) E-containing particles on LDL receptor binding of large, buoyant LDL subfractions (LDL I) from subjects with predominantly large (phenotype A) and small (phenotype B) LDL particles. Direct binding by human fibroblast LDL receptors was tested at 4 degrees C before and after removal of apoE-containing particles by immunoaffinity chromatography. The binding affinity of total LDL I in phenotype B was greater than that in phenotype A (Kd of 1.83+/-0.3 and 3.43+/-0.9 nmol/L, respectively, P<.05). LDL I from phenotype B subjects had a higher apoE to apoB molar ratio than did that from phenotype A (0.16+/-0.04 versus 0.06+/-0.02, P<.05). Nondenaturing gradient gel electrophoresis of apoE-containing LDL I isolated by immunoaffinity chromatography revealed a substantially larger peak particle diameter than in apoE-free LDL I, and comparison of LDL I composition before and after immunoaffinity chromatography suggested an increase in triglyceride content of apoE-containing particles. After removal of these particles, there was a greater than twofold reduction in LDL receptor affinity of phenotype B LDL (Kd of 1.83+/-0.3 to 3.76+/-0.6, P<.01), whereas in phenotype A no change was observed (Kd of 3.43+/-0.9 to 3.57+/-0.4, respectively). The receptor affinity of apoE-free LDL I from phenotype A and B subjects did not differ. These findings confirm that large, buoyant LDL particles from phenotype B subjects have a higher LDL receptor affinity than does LDL I from phenotype A subjects and suggest that this difference is due to an increased content of large, triglyceride-enriched, apoE-containing lipoproteins. It is possible that the accumulation of these particles reflects abnormalities in the metabolism of remnant lipoproteins that contribute to atherosclerosis risk in phenotype B subjects.

  20. Phosphatidylserine externalization and procoagulant activation of erythrocytes induced by Pseudomonas aeruginosa virulence factor pyocyanin.

    PubMed

    Qadri, Syed M; Donkor, David A; Bhakta, Varsha; Eltringham-Smith, Louise J; Dwivedi, Dhruva J; Moore, Jane C; Pepler, Laura; Ivetic, Nikola; Nazi, Ishac; Fox-Robichaud, Alison E; Liaw, Patricia C; Sheffield, William P

    2016-04-01

    The opportunistic pathogen Pseudomonas aeruginosa causes a wide range of infections in multiple hosts by releasing an arsenal of virulence factors such as pyocyanin. Despite numerous reports on the pleiotropic cellular targets of pyocyanin toxicity in vivo, its impact on erythrocytes remains elusive. Erythrocytes undergo an apoptosis-like cell death called eryptosis which is characterized by cell shrinkage and phosphatidylserine (PS) externalization; this process confers a procoagulant phenotype on erythrocytes as well as fosters their phagocytosis and subsequent clearance from the circulation. Herein, we demonstrate that P. aeruginosa pyocyanin-elicited PS exposure and cell shrinkage in erythrocyte while preserving the membrane integrity. Mechanistically, exposure of erythrocytes to pyocyanin showed increased cytosolic Ca(2+) activity as well as Ca(2+) -dependent proteolytic processing of μ-calpain. Pyocyanin further up-regulated erythrocyte ceramide abundance and triggered the production of reactive oxygen species. Pyocyanin-induced increased PS externalization in erythrocytes translated into enhanced prothrombin activation and fibrin generation in plasma. As judged by carboxyfluorescein succinimidyl-ester labelling, pyocyanin-treated erythrocytes were cleared faster from the murine circulation as compared to untreated erythrocytes. Furthermore, erythrocytes incubated in plasma from patients with P. aeruginosa sepsis showed increased PS exposure as compared to erythrocytes incubated in plasma from healthy donors. In conclusion, the present study discloses the eryptosis-inducing effect of the virulence factor pyocyanin, thereby shedding light on a potentially important mechanism in the systemic complications of P. aeruginosa infection. PMID:26781477

  1. [Influence of wholemeal bread on functional and structure characteristics erythrocytes membrane and lipids oxidation in fraction of microsome of internal organs in rats].

    PubMed

    Vitavskaia, A V; Khasiev, Kh Kh; Murzakhmetova, M K

    2006-01-01

    Acute tests in rats showed, that application of wholemeal bread into a standard vivarium ration (40 g per a rat with body weight 180-200 g) drastically impoves structural and functional characteristics of membranes of erlthrocytes and cells of a number of internal organs. Anhibition of peroxide oxidation of biological membranes lipids of internal organs (liver, ridneys, heart, lungs and brain) takes place, as well as impairment of erythrocytes membranes perkeability and increase of their peroxide resistivity.

  2. Oxidative Hemolysis of Erythrocytes

    ERIC Educational Resources Information Center

    Wlodek, Lidia; Kusior, Dorota

    2006-01-01

    This exercise for students will allow them to simultaneously observe lipid peroxidation and consequent hemolysis of rat erythrocytes and the effect of sodium azide, a catalase inhibitor, on these processes. It will also demonstrate a protective action of antioxidants, the therapeutically used N-acetylcysteine and albumins present in plasma.

  3. Horizontal transmission of a parasite is influenced by infected host phenotype and density.

    PubMed

    Roberts, K E; Hughes, W O H

    2015-02-01

    Transmission is a key determinant of parasite fitness, and understanding the dynamics of transmission is fundamental to the ecology and evolution of host-parasite interactions. Successful transmission is often reliant on contact between infected individuals and susceptible hosts. The social insects consist of aggregated groups of genetically similar hosts, making them particularly vulnerable to parasite transmission. Here we investigate how the ratio of infected to susceptible individuals impacts parasite transmission, using the honey bee, Apis mellifera and its microsporidian parasite Nosema ceranae. We used 2 types of infected hosts found simultaneously in colonies; sterile female workers and sexual males. We found a higher ratio of infected to susceptible individuals in groups resulted in a greater proportion of susceptibles becoming infected, but this effect was non-linear and interestingly, the ratio also affected the spore production of infected individuals. The transmission level was much greater in an experiment where the infected individuals were drones than in an experiment where they were workers, suggesting drones may act as intracolonial 'superspreaders'. Understanding the subtleties of transmission and how it is influenced by the phenotype of the infected/susceptible individuals is important for understanding pathogen transmission at population level, and for optimum targeting of parasite control strategies. PMID:25111753

  4. The influence of an innovative locomotor strategy on the phenotypic diversification of triggerfish (family: Balistidae).

    PubMed

    Dornburg, Alex; Sidlauskas, Brian; Santini, Francesco; Sorenson, Laurie; Near, Thomas J; Alfaro, Michael E

    2011-07-01

    Innovations in locomotor morphology have been invoked as important drivers of vertebrate diversification, although the influence of novel locomotion strategies on marine fish diversification remains largely unexplored. Using triggerfish as a case study, we determine whether the evolution of the distinctive synchronization of enlarged dorsal and anal fins that triggerfish use to swim may have catalyzed the ecological diversification of the group. By adopting a comparative phylogenetic approach to quantify median fin and body shape integration and to assess the tempo of functional and morphological evolution in locomotor traits, we find that: (1) functional and morphological components of the locomotive system exhibit a strong signal of correlated evolution; (2) triggerfish partitioned locomotor morphological and functional spaces early in their history; and (3) there is no strong evidence that a pulse of lineage diversification accompanied the major episode of phenotypic diversification. Together these findings suggest that the acquisition of a distinctive mode of locomotion drove an early radiation of shape and function in triggerfish, but not an early radiation of species.

  5. Influence of paternal preconception exposures on their offspring: through epigenetics to phenotype

    PubMed Central

    Day, Jonathan; Savani, Soham; Krempley, Benjamin D; Nguyen, Matthew; Kitlinska, Joanna B

    2016-01-01

    Historically, research into congenital defects has focused on maternal impacts on the fetal genome during gestation and prenatal periods. However, recent findings have sparked interest in epigenetic alterations of paternal genomes and its effects on offspring. This emergent field focuses on how environmental influences can epigenetically alter gene expression and ultimately change the phenotype and behavior of progeny. There are three primary mechanisms implicated in these changes: DNA methylation, histone modification, and miRNA expression. This paper provides a summary and subsequent review of past research, which highlights the significant impact of environmental factors on paternal germ cells during the lifetime of an individual as well as those of future generations. These findings support the existence of transgenerational epigenetic inheritance of paternal experiences. Specifically, we explore epidemiological and laboratory studies that demonstrate possible links between birth defects and paternal age, environmental factors, and alcohol consumption. Ultimately, our review highlights the clinical importance of these factors as well as the necessity for future research in the field. PMID:27335698

  6. Muscarinic signaling influences the patterning and phenotype of cholinergic amacrine cells in the developing chick retina

    PubMed Central

    Stanke, Jennifer J; Lehman, Bret; Fischer, Andy J

    2008-01-01

    Background Many studies in the vertebrate retina have characterized the differentiation of amacrine cells as a homogenous class of neurons, but little is known about the genes and factors that regulate the development of distinct types of amacrine cells. Accordingly, the purpose of this study was to characterize the development of the cholinergic amacrine cells and identify factors that influence their development. Cholinergic amacrine cells in the embryonic chick retina were identified by using antibodies to choline acetyltransferase (ChAT). Results We found that as ChAT-immunoreactive cells differentiate they expressed the homeodomain transcription factors Pax6 and Islet1, and the cell-cycle inhibitor p27kip1. As differentiation proceeds, type-II cholinergic cells, displaced to the ganglion cell layer, transiently expressed high levels of cellular retinoic acid binding protein (CRABP) and neurofilament, while type-I cells in the inner nuclear layer did not. Although there is a 1:1 ratio of type-I to type-II cells in vivo, in dissociated cell cultures the type-I cells (ChAT-positive and CRABP-negative) out-numbered the type-II cells (ChAT and CRABP-positive cells) by 2:1. The relative abundance of type-I to type-II cells was not influenced by Sonic Hedgehog (Shh), but was affected by compounds that act at muscarinic acetylcholine receptors. In addition, the abundance and mosaic patterning of type-II cholinergic amacrine cells is disrupted by interfering with muscarinic signaling. Conclusion We conclude that: (1) during development type-I and type-II cholinergic amacrine cells are not homotypic, (2) the phenotypic differences between these subtypes of cells is controlled by the local microenvironment, and (3) appropriate levels of muscarinic signaling between the cholinergic amacrine cells are required for proper mosaic patterning. PMID:18254959

  7. Influence of subacute treatment of some plant growth regulators on serum marker enzymes and erythrocyte and tissue antioxidant defense and lipid peroxidation in rats.

    PubMed

    Celik, Ismail; Tuluce, Yasin; Isik, Ismail

    2006-01-01

    This study aims to investigate the effects of the plant growth regulators (PGRs) (2,3,5-triiodobenzoic acid (TIBA), Naphthaleneacetic acid (NAA), and 2,4-dichlorofenoxyacetic acid (2,4-D)) on serum marker enzymes (aspartate aminotransferase (AST), alanin aminotransferase (ALT), creatine phosphokinase (CPK), and lactate dehydrogenase (LDH)), antioxidant defense systems (reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST), and catalase (CAT)), and lipid peroxidation content (malondialdehyde = MDA) in various tissues of rats. 50 and 100 ppm of PGRs as drinking water were administered orally to rats (Sprague-Dawley albino) ad libitum for 25 days continuously. The PGRs treatment caused different effects on the serum marker enzymes, antioxidant defense systems, and the MDA content in experimented rats compared to controls. Results showed that TIBA caused a significant decrease in serum AST activity with both the dosage whereas serum CPK was significantly increased with 100 ppm dosage of TIBA. Meanwhile, serum AST, CPK, and LDH activities were significantly increased with both dosage of NAA and 2,4-D. The lipid peroxidation end-product MDA significantly increased in the all tissues treated with both dosages of PGRs without any change in the brain and erythrocyte of rats treated with both the dosages of 2,4-D. The GSH depletion in the kidney and brain tissues of rats treated with both dosages of PGRs was found to be significant. Furthermore, the GSH depletion in the erythrocyte of rats treated with both dosages of PGRs except 50 ppm dosage of 2,4-D was significant too. Also, the GSH level in the liver was significantly depleted with 50 ppm of 2,4-D and NAA, whereas the GSH depletion in the same tissue did not significantly change with the treatment. The activity of antioxidant enzymes was also seriously affected by PGRs; SOD significantly decreased in the liver, heart, kidney, and brain of rats treated with

  8. Influence of Cartilage Extracellular Matrix Molecules on Cell Phenotype and Neocartilage Formation

    PubMed Central

    Grogan, Shawn P.; Chen, Xian; Sovani, Sujata; Taniguchi, Noboru; Colwell, Clifford W.; Lotz, Martin K.

    2014-01-01

    Interaction between chondrocytes and the cartilage extracellular matrix (ECM) is essential for maintaining the cartilage's role as a low-friction and load-bearing tissue. In this study, we examined the influence of cartilage zone-specific ECM on human articular chondrocytes (HAC) in two-dimensional and three-dimensional (3D) environments. Two culture systems were used. SYSTEM 1: HAC were cultured on cell-culture plates that had been precoated with the following ECM molecules for 7 days: decorin, biglycan, tenascin C (superficial zone), collagen type II, hyaluronan (HA) (middle and deep zones), and osteopontin (deep zone). Uncoated standard culture plates were used as controls. Expanded cells were examined for phenotypic changes using real-time polymerase chain reaction. In addition, expanded cells were placed into high-density pellet cultures for 14 days. Neocartilage formation was assessed via gene expression and histology evaluations. SYSTEM 2: HAC that were cultured on untreated plates and encapsulated in a 3D alginate scaffold were mixed with one of the zone-specific ECM molecules. Cell viability, gene expression, and histology assessments were conducted on 14-day-old tissues. In HAC monolayer culture, exposure to decorin, HA, and osteopontin increased COL2A1 and aggrecan messenger RNA (mRNA) levels compared with controls. Biglycan up-regulated aggrecan without a significant impact on COL2A1 expression; Tenascin C reduced COL2A1 expression. Neocartilage formed after preculture on tenascin C and collagen type II expressed higher COL2A1 mRNA compared with control pellets. Preculture of HAC on HA decreased both COL2A1 and aggrecan expression levels compared with controls, which was consistent with histology. Reduced proteoglycan 4 (PRG4) mRNA levels were observed in HAC pellets that had been precultured with biglycan and collagen type II. Exposing HAC to HA directly in 3D-alginate culture most effectively induced neocartilage formation, showing increased COL2A1

  9. Hyperlipoproteinaemia in primary gout: hyperlipoproteinaemic phenotype and influence of alcohol intake and obesity in Japan.

    PubMed Central

    Jiao, S; Kameda, K; Matsuzawa, Y; Tarui, S

    1986-01-01

    Serum lipoprotein profiles were investigated in 108 male patients with primary gout before treatment to elucidate the prevalence of each individual phenotype of coexisting hyperlipoproteinaemia and pathogenic factors responsible for it. The mean serum triglyceride (TG) and total cholesterol (TC) levels in the patients with gout were 2.10 +/- 0.14 mmol/l and 5.26 +/- 0.10 mmol/l (mean +/- SEM) respectively, which were significantly higher (p less than 0.01 and p less than 0.05 respectively) than the levels in age matched controls without gout (1.30 +/- 0.07 mmol/l and 4.77 +/- 0.08 mmol/l respectively). Serum high density lipoprotein cholesterol (HDL-C) values were slightly decreased in patients with gout compared with controls (1.24 +/- 0.08 mmol/l v 1.40 +/- 0.03 mmol/l, p less than 0.05). Hyperlipoproteinaemia was seen in 61 patients (56%), of whom patients with type IIa, IIb, and IV hyperlipoproteinaemia formed 13, 15, and 69% respectively. Thus the prevalence of type IV hyperlipoproteinaemia was high in primary gout as compared with primary hyperlipoproteinaemia with primary hyperlipoproteinaemia (69% v 43%, p less than 0.01). The independent and relative influences of clinical data of the patients upon the concentrations of serum lipids were assessed by stepwise multiple regression analysis. Two major predictors of serum TG level were alcohol intake (p less than 0.01) and serum uric acid level (p less than 0.05). The most significant predictive variable was alcohol intake, but its influence was judged to be small (r2 = 0.067). None of the other variables, including obesity index, had any significant influence. The relationships between any of these variables and serum TC or HDL-C levels were not significant. In addition, serum lipid levels were investigated in patients with neither obesity (defined as 120% or more of ideal body weight) nor a history of alcohol intake. Their serum TG and TC concentrations were also significantly higher than the respective

  10. Influence of abnormally high leptin levels during pregnancy on metabolic phenotypes in progeny mice.

    PubMed

    Makarova, Elena N; Chepeleva, Elena V; Panchenko, Polina E; Bazhan, Nadezhda M

    2013-12-01

    Maternal obesity increases the risk of obesity in offspring, and obesity is accompanied by an increase in blood leptin levels. The "yellow" mutation at the mouse agouti locus (A(y)) increases blood leptin levels in C57BL preobese pregnant mice without affecting other metabolic characteristics. We investigated the influence of the A(y) mutation or leptin injection at the end of pregnancy in C57BL mice on metabolic phenotypes and the susceptibility to diet-induced obesity (DIO) in offspring. In both C57BL-A(y) and leptin-treated mice, the maternal effect was more pronounced in male offspring. Compared with males born to control mothers, males born to A(y) mothers displayed equal food intake (FI) but decreased body weight (BW) gain after weaning, equal glucose tolerance, and enhanced FI-to-BW ratios on the standard diet but the same FI and BW on the high-fat diet. Males born to A(y) mothers were less responsive to the anorectic effect of exogenous leptin and less resistant to fasting (were not hyperphagic and gained less weight during refeeding after food deprivation) compared with males born to control mothers. However, all progeny displayed equal hypothalamic expression of Agouti gene-related protein (AgRP), neuropeptide Y (NPY), and proopiomelanocortin (POMC) and equal plasma leptin and glucose levels after food deprivation. Leptin injections in C57BL mice on day 17 of pregnancy decreased BW in both male and female offspring but inhibited FI and DIO only in male offspring. Our results show that hyperleptinemia during pregnancy has sex-specific long-term effects on energy balance regulation in progeny and does not predispose offspring to developing obesity.

  11. Interleukin-6 promoter polymorphism interacts with pain and life stress influencing depression phenotypes.

    PubMed

    Kovacs, David; Eszlari, Nora; Petschner, Peter; Pap, Dorottya; Vas, Szilvia; Kovacs, Peter; Gonda, Xenia; Bagdy, Gyorgy; Juhasz, Gabriella

    2016-05-01

    Interleukin-6 (IL-6) has emerged as a potent biomarker for depression as its elevated plasma levels in patients with clinical depression have been confirmed by meta-analyses. Increased plasma IL-6 concentration was associated with various psychological stress factors and physical disorders accompanied by pain. Another modulator of the IL-6 level is rs1800795, a promoter polymorphism in the IL-6 gene which is able to influence its expression rate. Therefore, we examined in a Hungarian population sample of 1053 volunteers with European origins if rs1800795 polymorphism can affect depression symptoms measured by Zung Self-rating Depression Scale (ZSDS), and Brief Symptom Inventory (BSI). We also investigated the interactions of the polymorphism with reported painful physical conditions and Recent Negative Life Events (RLE) measured by the List of Life Threatening Experiences. Rs1800795 significantly interacted with both RLE and painful condition on depressive symptoms measured by ZSDS and BSI using different heritability models, while no main effects of the polymorphism were identified. After correction for multiple testing only the rs1800795 × RLE interaction effect (recessive model) remained significant on the BSI score, while both RLE and painful conditions significantly interacted on the ZSDS. In conclusion, the functional IL-6 rs1800795 polymorphism in interaction with various stress factors increases the risk of depression and has a greater impact on symptoms measured by the ZSDS. Thus, IL-6 and other cytokines may be more relevant in the development of somatic symptoms compared to affective signs of depression, delineating a specific genotype-phenotype relationship in this heterogeneous disorder.

  12. [Study of the influence of low-dose γ-irradiation on the functional state of peripheral blood erythrocytes of rats].

    PubMed

    Izmest'eva, O S; Luzianina, A A; Ershova, I L; Zhavoronkov, L P

    2014-01-01

    Low-intensity radiation at the absorbed dose of 4 μGy/min is a stressor of medium strength. In male Wistar rats, a pronounced and long-lasting response occurs in the system of red blood cells at the accumulated dose of 4.8 mGy. Functional deficiency of circulating cells was evaluated by the resistance of erythrocytes to acid lyse and the activity of the main antioxidant enzymes--superoxide dismutase (SOD) and catalase (CAT). The minimum "threshold" doses of radiation that cause systemic reactions occur in the range of units of miligrey. PMID:25775841

  13. Preactivation and phenotype of monocytes have no influence on their elimination from culture by activated T lymphocytes.

    PubMed

    Pryjma, J; Zembala, M; Ernst, M; Flad, H D

    1995-01-01

    T lymphocytes can kill antigen-presenting cells (APC) in the presence of antigen or lectin. The subject of this study was to investigate whether the state of activation or phenotype of monocytes, influence their susceptibility to killing by T cells activated with pokeweed mitogen (PWM) or anti-CD3 monoclonal antibody. The data are presented which show that monocytes activation with cytokines (IFN-gamma, IL-4, or IL-2), PPD, phorbol ester or phagocytic stimulus, have no influence on monocyte susceptibility to killing by T lymphocytes. Furthermore, flow cytometry data suggest that monocytes eliminated from culture have no characteristic phenotype. In conclusion, our data indicate that elimination of monocytes by activated T lymphocytes does not depend on the state of activation of monocytes.

  14. Genetic and environmental influences on objective intermediate asthma phenotypes in Dutch twins.

    PubMed

    Wu, T; Boezen, H M; Postma, D S; Los, H; Postmus, P E; Snieder, H; Boomsma, D I

    2010-08-01

    It is unclear to what extent the same set of environmental or genetic factors regulate objective intermediate asthma phenotypes. We examined heritabilities of these phenotypes and estimated their environmental and genetic overlap. We studied baseline lung function (forced expiratory volume in 1 s (FEV(1)), forced vital capacity (FVC) and FEV(1)/FVC), bronchial hyperresponsiveness, number of positive skin prick tests (SPT) to 11 allergens, serum total immunoglobulin (Ig)E, number of positive specific IgE tests to four allergens and eosinophil counts. 103 twin pairs were studied (46 monozygotic and 57 dizygotic; mean age: 22.5 yrs, range: 17.0-27.0 yrs). Univariate and bivariate genetic analyses were performed after adjustment for significant covariates. All intermediate asthma phenotypes showed significant heritabilities (47-83%). Most phenotypes were substantially correlated, which was mainly due to shared genetic factors. Pairs of phenotypes with the largest genetic correlations were specific IgE and SPT (0.98), and total IgE with specific IgE (0.87), with SPT (0.72), and with eosinophils (0.62). SPT showed significant environmental correlations with total IgE (0.65), specific IgE (0.70) and bronchial hyperresponsiveness (0.44). Genetic effects explain the majority of the variation in objective intermediate asthma phenotypes. Additionally, correlations between pairs of these traits are also mainly explained by genetic rather than environmental factors. PMID:20075051

  15. The influence of gene flow and drift on genetic and phenotypic divergence in two species of Zosterops in Vanuatu

    PubMed Central

    Clegg, Sonya M.; Phillimore, Albert B.

    2010-01-01

    Colonization of an archipelago sets the stage for adaptive radiation. However, some archipelagos are home to spectacular radiations, while others have much lower levels of diversification. The amount of gene flow among allopatric populations is one factor proposed to contribute to this variation. In island colonizing birds, selection for reduced dispersal ability is predicted to produce changing patterns of regional population genetic structure as gene flow-dominated systems give way to drift-mediated divergence. If this transition is important in facilitating phenotypic divergence, levels of genetic and phenotypic divergence should be associated. We consider population genetic structure and phenotypic divergence among two co-distributed, congeneric (Genus: Zosterops) bird species inhabiting the Vanuatu archipelago. The more recent colonist, Z. lateralis, exhibits genetic patterns consistent with a strong influence of distance-mediated gene flow. However, complex patterns of asymmetrical gene flow indicate variation in dispersal ability or inclination among populations. The endemic species, Z. flavifrons, shows only a partial transition towards a drift-mediated system, despite a long evolutionary history on the archipelago. We find no strong evidence that gene flow constrains phenotypic divergence in either species, suggesting that levels of inter-island gene flow do not explain the absence of a radiation across this archipelago. PMID:20194170

  16. The influence of gene flow and drift on genetic and phenotypic divergence in two species of Zosterops in Vanuatu.

    PubMed

    Clegg, Sonya M; Phillimore, Albert B

    2010-04-12

    Colonization of an archipelago sets the stage for adaptive radiation. However, some archipelagos are home to spectacular radiations, while others have much lower levels of diversification. The amount of gene flow among allopatric populations is one factor proposed to contribute to this variation. In island colonizing birds, selection for reduced dispersal ability is predicted to produce changing patterns of regional population genetic structure as gene flow-dominated systems give way to drift-mediated divergence. If this transition is important in facilitating phenotypic divergence, levels of genetic and phenotypic divergence should be associated. We consider population genetic structure and phenotypic divergence among two co-distributed, congeneric (Genus: Zosterops) bird species inhabiting the Vanuatu archipelago. The more recent colonist, Z. lateralis, exhibits genetic patterns consistent with a strong influence of distance-mediated gene flow. However, complex patterns of asymmetrical gene flow indicate variation in dispersal ability or inclination among populations. The endemic species, Z. flavifrons, shows only a partial transition towards a drift-mediated system, despite a long evolutionary history on the archipelago. We find no strong evidence that gene flow constrains phenotypic divergence in either species, suggesting that levels of inter-island gene flow do not explain the absence of a radiation across this archipelago.

  17. Comparative Analyses of QTLs Influencing Obesity and Metabolic Phenotypes in Pigs and Humans

    PubMed Central

    Jacobsen, Mette J.; Cirera, Susanna; Kogelman, Lisette J. A.; Bruun, Camilla S.; Mark, Thomas; Jørgensen, Claus B.; Grarup, Niels; Appel, Emil V. R.; Galjatovic, Ehm A. A.; Hansen, Torben; Pedersen, Oluf; Guerin, Maryse; Huby, Thierry; Lesnik, Philipppe; Meuwissen, Theo H. E.; Kadarmideen, Haja N.; Fredholm, Merete

    2015-01-01

    The pig is a well-known animal model used to investigate genetic and mechanistic aspects of human disease biology. They are particularly useful in the context of obesity and metabolic diseases because other widely used models (e.g. mice) do not completely recapitulate key pathophysiological features associated with these diseases in humans. Therefore, we established a F2 pig resource population (n = 564) designed to elucidate the genetics underlying obesity and metabolic phenotypes. Segregation of obesity traits was ensured by using breeds highly divergent with respect to obesity traits in the parental generation. Several obesity and metabolic phenotypes were recorded (n = 35) from birth to slaughter (242 ± 48 days), including body composition determined at about two months of age (63 ± 10 days) via dual-energy x-ray absorptiometry (DXA) scanning. All pigs were genotyped using Illumina Porcine 60k SNP Beadchip and a combined linkage disequilibrium-linkage analysis was used to identify genome-wide significant associations for collected phenotypes. We identified 229 QTLs which associated with adiposity- and metabolic phenotypes at genome-wide significant levels. Subsequently comparative analyses were performed to identify the extent of overlap between previously identified QTLs in both humans and pigs. The combined analysis of a large number of obesity phenotypes has provided insight in the genetic architecture of the molecular mechanisms underlying these traits indicating that QTLs underlying similar phenotypes are clustered in the genome. Our analyses have further confirmed that genetic heterogeneity is an inherent characteristic of obesity traits most likely caused by segregation or fixation of different variants of the individual components belonging to cellular pathways in different populations. Several important genes previously associated to obesity in human studies, along with novel genes were identified. Altogether, this study provides novel insight that

  18. Genetic markers that influence feed efficiency phenotypes also affect cattle temperament as measured by flight speed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The measure of flight speed for cattle has been shown to be a predictive indicator of temperament and has also been associated with feed efficiency phenotypes, thus, genetic markers associated with both traits may assist with the selection of animals with calmer disposition and economic value. Chrom...

  19. Multiple cues influence multiple traits in the phenotypically plastic melanization of the cabbage white butterfly.

    PubMed

    Stoehr, Andrew M; Wojan, Erin M

    2016-11-01

    Phenotypic plasticity, or the ability of organisms to produce different phenotypes depending upon environmental factors, may be adaptive in varying environments. However, because environments differ in many ways and organisms consist of many traits perfect phenotype-environment matches are unlikely. Studies that investigate multiple interacting environmental factors and the plastic responses of multiple traits should increase our understanding of the limits of adaptive plasticity. We experimentally examined the effects of variation in temperature and photoperiod on the seasonally plastic, and likely adaptive, melanization of a temperate butterfly, Pieris rapae. Although several melanin-based traits changed in response to temperature and photoperiodic variation, these traits tended to fall into two 'trait groups' consisting of traits covarying positively. However, these two trait groups responded to environmental factors, particularly temperature, in independent and sometimes opposing ways, with one increasing and the other decreasing in melanization with increased temperature. In some cases, plastic responses were complex and non-linear. Furthermore, when temperature and photoperiod were manipulated orthogonally, we sometimes detected interactive effects on melanization. These complex responses to two environmental cues may reflect sub-optimal responses or may occur if the two cues together provide more reliable information about future conditions than would either cue alone. Our results highlight the limits of studies of phenotypic plasticity that consider only single environmental factors and limit treatments to just two levels. PMID:27417547

  20. Aggregation ability of erythrocytes of patients with coronary heart disease depending on different glucose concentration

    NASA Astrophysics Data System (ADS)

    Malinova, Lidia I.; Simonenko, Georgy V.; Kirichuk, Vyacheslav F.; Denisova, Tatyana P.; Tuchin, Valery V.

    2002-07-01

    The aggregation ability of erythrocytes of patients with coronary heart disease comparing to practically healthy persons and patients with coronary heart disease combined with non insulin dependent diabetes mellitus depending on different glucose concentration in unguentums of blood incubates with the help of computer microphotometer - visual analyzer was studied. Two-phase behavior of erythrocytes size changing of practically healthy persons depending on glucose concentration in an incubation medium and instability erythrocyte systems of a whole blood to the influence of high glucose concentration were revealed. Influence of high glucose concentration on aggregation ability of erythrocytes of patients with coronary heart disease and its combination with non insulin dependent diabetes mellitus was revealed.

  1. Phenotypic plasticity influences the size, shape and dynamics of the geographic distribution of an invasive plant.

    PubMed

    Pichancourt, Jean-Baptiste; van Klinken, Rieks D

    2012-01-01

    Phenotypic plasticity has long been suspected to allow invasive species to expand their geographic range across large-scale environmental gradients. We tested this possibility in Australia using a continental scale survey of the invasive tree Parkinsonia aculeata (Fabaceae) in twenty-three sites distributed across four climate regions and three habitat types. Using tree-level responses, we detected a trade-off between seed mass and seed number across the moisture gradient. Individual trees plastically and reversibly produced many small seeds at dry sites or years, and few big seeds at wet sites and years. Bigger seeds were positively correlated with higher seed and seedling survival rates. The trade-off, the relation between seed mass, seed and seedling survival, and other fitness components of the plant life-cycle were integrated within a matrix population model. The model confirms that the plastic response resulted in average fitness benefits across the life-cycle. Plasticity resulted in average fitness being positively maintained at the wet and dry range margins where extinction risks would otherwise have been high ("Jack-of-all-Trades" strategy JT), and fitness being maximized at the species range centre where extinction risks were already low ("Master-of-Some" strategy MS). The resulting hybrid "Jack-and-Master" strategy (JM) broadened the geographic range and amplified average fitness in the range centre. Our study provides the first empirical evidence for a JM species. It also confirms mechanistically the importance of phenotypic plasticity in determining the size, the shape and the dynamic of a species distribution. The JM allows rapid and reversible phenotypic responses to new or changing moisture conditions at different scales, providing the species with definite advantages over genetic adaptation when invading diverse and variable environments. Furthermore, natural selection pressure acting on phenotypic plasticity is predicted to result in maintenance

  2. Phenotypic Plasticity Influences the Size, Shape and Dynamics of the Geographic Distribution of an Invasive Plant

    PubMed Central

    Pichancourt, Jean-Baptiste; van Klinken, Rieks D.

    2012-01-01

    Phenotypic plasticity has long been suspected to allow invasive species to expand their geographic range across large-scale environmental gradients. We tested this possibility in Australia using a continental scale survey of the invasive tree Parkinsonia aculeata (Fabaceae) in twenty-three sites distributed across four climate regions and three habitat types. Using tree-level responses, we detected a trade-off between seed mass and seed number across the moisture gradient. Individual trees plastically and reversibly produced many small seeds at dry sites or years, and few big seeds at wet sites and years. Bigger seeds were positively correlated with higher seed and seedling survival rates. The trade-off, the relation between seed mass, seed and seedling survival, and other fitness components of the plant life-cycle were integrated within a matrix population model. The model confirms that the plastic response resulted in average fitness benefits across the life-cycle. Plasticity resulted in average fitness being positively maintained at the wet and dry range margins where extinction risks would otherwise have been high (“Jack-of-all-Trades” strategy JT), and fitness being maximized at the species range centre where extinction risks were already low (“Master-of-Some” strategy MS). The resulting hybrid “Jack-and-Master” strategy (JM) broadened the geographic range and amplified average fitness in the range centre. Our study provides the first empirical evidence for a JM species. It also confirms mechanistically the importance of phenotypic plasticity in determining the size, the shape and the dynamic of a species distribution. The JM allows rapid and reversible phenotypic responses to new or changing moisture conditions at different scales, providing the species with definite advantages over genetic adaptation when invading diverse and variable environments. Furthermore, natural selection pressure acting on phenotypic plasticity is predicted to result in

  3. Environmental influences on the Indo–Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    PubMed Central

    Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo–Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippuris Linnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests—but does not confirm—that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulata Nutting, 1910, Isis minorbrachyblasta Zou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the

  4. Environmental influences on the Indo-Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    PubMed

    Rowley, Sonia J; Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo-Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippurisLinnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests-but does not confirm-that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulataNutting, 1910, Isis minorbrachyblastaZou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the Isididae is in

  5. Environmental influences on the Indo-Pacific octocoral Isis hippuris Linnaeus 1758 (Alcyonacea: Isididae): genetic fixation or phenotypic plasticity?

    PubMed

    Rowley, Sonia J; Pochon, Xavier; Watling, Les

    2015-01-01

    As conspicuous modular components of benthic marine habitats, gorgonian (sea fan) octocorals have perplexed taxonomists for centuries through their shear diversity, particularly throughout the Indo-Pacific. Phenotypic incongruence within and between seemingly unitary lineages across contrasting environments can provide the raw material to investigate processes of disruptive selection. Two distinct phenotypes of the Isidid Isis hippurisLinnaeus, 1758 partition between differing reef environments: long-branched bushy colonies on degraded reefs, and short-branched multi/planar colonies on healthy reefs within the Wakatobi Marine National Park (WMNP), Indonesia. Multivariate analyses reveal phenotypic traits between morphotypes were likely integrated primarily at the colony level with increased polyp density and consistently smaller sclerite dimensions at the degraded site. Sediment load and turbidity, hence light availability, primarily influenced phenotypic differences between the two sites. This distinct morphological dissimilarity between the two sites is a reliable indicator of reef health; selection primarily acting on colony morphology, porosity through branching structure, as well as sclerite diversity and size. ITS2 sequence and predicted RNA secondary structure further revealed intraspecific variation between I. hippuris morphotypes relative to such environments (ΦST = 0.7683, P < 0.001). This evidence suggests-but does not confirm-that I. hippuris morphotypes within the WMNP are two separate species; however, to what extent and taxonomic assignment requires further investigation across its full geographic distribution. Incongruence between colonies present in the WMNP with tenuously described Isis alternatives (Isis reticulataNutting, 1910, Isis minorbrachyblastaZou, Huang & Wang, 1991), questions the validity of such assignments. Furthermore, phylogenetic analyses confirm early taxonomic suggestion that the characteristic jointed axis of the Isididae is in

  6. Phenotypic heterogeneity influences the behavior of rat aortic smooth muscle cells in collagen lattice

    SciTech Connect

    Orlandi, Augusto . E-mail: orlandi@uniroma2.it; Ferlosio, Amedeo; Gabbiani, Giulio; Spagnoli, Luigi Giusto; Ehrlich, Paul H.

    2005-12-10

    Phenotypic modulation of vascular smooth muscle cells (SMCs) in atherosclerosis and restenosis involves responses to the surrounding microenvironment. SMCs obtained by enzymatic digestion from tunica media of newborn, young adult (YA) and old rats and from the thickened intima (TI) and underlying media of young adult rat aortas 15 days after ballooning were entrapped in floating populated collagen lattice (PCL). TI-SMCs elongated but were poor at PCL contraction and remodeling and expressed less {alpha}2 integrin compared to other SMCs that appeared more dendritic. During early phases of PCL contraction, SMCs showed a marked decrease in the expression of {alpha}-smooth muscle actin and myosin. SMCs other than TI-SMCs required 7 days to re-express {alpha}-smooth muscle actin and myosin. Only TI-SMCs in PCL were able to divide in 48 h, with a greater proportion in S and G2-M cell cycle phases compared to other SMCs. Anti-{alpha}2 integrin antibody markedly inhibited contraction but not proliferation in YA-SMC-PLCs; anti-{alpha}1 and anti-{alpha}2 integrin antibodies induced a similar slight inhibition in TI-SMC-PCLs. Finally, TI-SMCs rapidly migrated from PCL on plastic reacquiring their epithelioid phenotype. Heterogeneity in proliferation and cytoskeleton as well the capacity to remodel the extracellular matrix are maintained, when SMCs are suspended in PCLs.

  7. Influence of phenotype conversion of epicardial adipocytes on the coronary atherosclerosis and its potential molecular mechanism

    PubMed Central

    Wang, Jing; Chen, Dong; Cheng, Xun-Min; Zhang, Qi-Gao; Peng, Yong-Ping; Wang, Li-Jun; He, Song-Qing; Gong, Jian-Bin

    2015-01-01

    Objective: To investigate the phenotype conversion of epicardial adipocytes and its potential molecular mechanism during the occurrence and development of coronary atherosclerosis. Methods: A total of 30 health male New Zealand white rabbits were used. In experiment group (n=15), rabbits were fed with high fat food to establish atherosclerosis animal model; rabbits in control group (n=15) were fed with normal food. Results: At week 0, UCP-1 and PPARγ mRNA expressions in EAT and sBAT were significantly higher than in eWAT, and leptin mRNA expression lower than (P<0.05). In experiment group, the mRNA expressions of UCP-1 and PPARγ reduced gradually, but leptin mRNA increased progressively in EAT (P<0.05). UCP-1 expression reduced gradually, the newly generated blood vessels reduced significantly, but leptin and RAM11 increased gradually (P<0.05). The adipocyte volume in EAT increased gradually, but the adipocyte number reduced progressively (P<0.05). The number of mitochondria with multiple crests reduced gradually in EAT; IL-6 reduced the mRNA expressions of UCP-1 and PPARγ in adipocytes of BAT in a dose dependent manner, but it increased the mRNA expressions of leptin and STAT3 (P<0.05). In the presence of IL-6, JSI-124 increased the mRNA expressions of UCP-1 and PPAR-γ in adipocytes of BAT in a dose dependent manner, but it reduced the mRNA expressions of leptin and STAT3 (P<0.05). Conclusion: During the progression of atherosclerosis, there is a phenotype conversion of EAT from BAT to WAT, which further promotes the focal occurrence and development of atherosclerosis; IL-6 may activate JAK-STAT3 pathway to induce this conversion. PMID:26692919

  8. Body composition of the host influences dendritic cell phenotype in patients treated for colorectal cancer.

    PubMed

    Malietzis, George; Lee, Gui Han; Al-Hassi, Hafid O; Bernardo, David; Blakemore, Alexandra I F; Kennedy, Robin H; Moorghen, Morgan; Jenkins, John T; Knight, Stella C

    2016-08-01

    Dendritic cells (DCs) are antigen-presenting cells that can acquire tumour antigens and initiate cytotoxic T cell reactions. Obesity has been proposed as a cause for tumours escaping immune surveillance, but few studies investigate the impact of other body composition parameters. We examined the relationship of DC phenotype with computer tomography (CT)-defined parameters in patients with colorectal cancer (CRC). DCs were identified within peripheral blood mononuclear cells by flow cytometry as HLA-DR positive and negative for markers of other cell lineages in 21 patients. Analysis of CT scans was used to calculate lumbar skeletal muscle index (LSMI) and mean muscle attenuation (MA). Positive correlation between the LSMI and expression of CD40 in all DCs (r = 0.45; p = 0.04) was demonstrated. The MA was positively correlated with scavenger receptor CD36 [all DCs (r = 0.60; p = 0.01) and myeloid DCs (r = 0.63; p < 0.01)]. However, the MA was negatively correlated with CCR7 expression in all DCs (r = -0.46, p = 0.03.) and with CD83 [all DCs (r = -0.63; p = 0.01) and myeloid DCs (r = -0.75; p < 0.01)]. There were no relationships between the fat indexes and the DC phenotype. These results highlight a direct relationship between muscle depletion and changes in stimulatory, migratory and fatty acid-processing potential of DC in patients with CRC. PMID:26960692

  9. Transcriptome analyses of Atlantic salmon (Salmo salar L.) erythrocytes infected with piscine orthoreovirus (PRV).

    PubMed

    Dahle, Maria Krudtaa; Wessel, Øystein; Timmerhaus, Gerrit; Nyman, Ingvild Berg; Jørgensen, Sven Martin; Rimstad, Espen; Krasnov, Aleksei

    2015-08-01

    Heart and skeletal muscle inflammation (HSMI) is a widespread disease of farmed Atlantic salmon (Salmo salar L.) and is associated with piscine orthoreovirus (PRV) infection. PRV is detectable in blood long before development of pathology in cardiac- and skeletal muscle appear, and erythrocytes have been identified as important target cells for the virus. The effects of PRV infection on cellular processes of erythrocytes are not known, but haemolytic anemia or systemic lysis of erythrocytes does not seem to occur, even with high virus loads in erythrocytes. In this study, gene expression profiling performed with high-density oligonucleotide microarray showed that PRV infection of erythrocytes induced a large panel of virus responsive genes. These involved interferon-regulated antiviral genes, as well as genes involved in antigen presentation via MHC class I. PRV infection also stimulated negative immune regulators. In contrast, a large number of immune genes expressed prior to infection were down-regulated. Moderate reduction of expression was also found for many genes encoding components of cytoskeleton and myofiber, proteins involved in metabolism, ion exchange, cell-cell interactions as well as growth factors and regulators of differentiation. PRV did not affect expression of genes involved in heme biosynthesis, gas exchange or erythrocyte-specific markers, but some regulators of erythropoiesis showed decreased transcription levels. These results indicate that PRV infection activates innate antiviral immunity in salmon erythrocytes, but suppresses other gene expression programs. Gene expression profiles suggest major phenotypic changes in PRV infected erythrocytes, but the functional consequences remain to be explored.

  10. Squamous Carcinoma Cells Influence Monocyte Phenotype and Suppress Lipopolysaccharide-Induced TNF-alpha in Monocytes

    PubMed Central

    Lam-ubol, Aroonwan; Hopkin, Dustin; Letuchy, Elena M.; Kurago, Zoya B.

    2010-01-01

    Bacteria and chronic inflammation are present in squamous cell carcinoma of the head and neck (HNSCC), but their roles in the pathogenesis of HNSCC are unclear. Our studies described here revealed that human monocytes co-cultured short term with HNSCC cells were more likely to express CD16, and CD16+ small mononuclear cells were common in HNSCC specimens. In addition, we identified monocytes as the primary source of LPS-induced IL-6 and TNF-alpha in the monocyte-HNSCC co-cultures. Remarkably, relative to LPS-stimulated monocytes cultured alone, HNSCC cells profoundly suppressed LPS-induced TNF-alpha in monocytes, without compromising IL-6 production. High levels of cytoprotective factors like IL-6 and low levels of TNF-alpha are important for the tumor microenvironment that enables tumor cell survival, affects monocyte differentiation and may contribute to tumor colonization by bacteria. This study provides novel observations that HNSCC cells affect monocyte phenotype and function, which are relevant to the regulation of the HNSCC microenvironment. PMID:20084448

  11. Influence of Sex on Suicidal Phenotypes in Affective Disorder Patients with Traumatic Childhood Experiences

    PubMed Central

    Carlberg, Laura; Swoboda, Patrick; Ludwig, Birgit; Koller, Romina; Kapusta, Nestor D.; Aigner, Martin; Haslacher, Helmuth; Schmöger, Michaela; Kasper, Siegfried; Schosser, Alexandra

    2015-01-01

    Objectives In the current study, we aimed to investigate the impact of childhood trauma on suicidal behaviour phenotypes in a group of patients with diagnosed affective disorder (unipolar or bipolar affective disorder). Patients and Methods Patients with and without a history of childhood abuse, measured by Childhood Trauma Questionnaire (CTQ), were assessed to explore risks for suicidal behaviour (including suicide attempt, self-harm and non-suicidal self-injury). The tested sample consisted of 258 patients (111 males and 147 females, in-patients and out-patients at the Department of Psychiatry and Psychotherapy, Medical University of Vienna and University Hospital Tulln, Lower Austria). Psychiatric diagnoses were derived from the SCAN (Schedules for Clinical Assessment in Neuropsychiatry) interview. In addition, patients were administered the Lifetime Parasuicidal Count (LPC), Suicidal Behaviour Questionnaire (SBQ-R), and Viennese Suicide Risk Assessment Scale (VISURIAS) questionnaires. Results In contrast to male suicide attempters, female suicide attempters showed both significantly higher total CTQ scores (p<0.001), and higher CTQ subscores (emotional, physical and sexual abuse, as well as emotional and physical neglect) in comparison to the non-suicidal control group. Besides, females with a history of self-harming behaviour (including suicidal intention) and Non-Suicidal-Self Injury (NSSI) had significantly higher CTQ total scores (p<0.001) than the control group. Conclusion These findings suggest gender differences in suicidal behaviour after being exposed to childhood trauma. PMID:26366559

  12. The Specificity of Targeted Vaccines for APC Surface Molecules Influences the Immune Response Phenotype

    PubMed Central

    Grødeland, Gunnveig; Mjaaland, Siri; Tunheim, Gro; Fredriksen, Agnete B.; Bogen, Bjarne

    2013-01-01

    Different diseases require different immune responses for efficient protection. Thus, prophylactic vaccines should prime the immune system for the particular type of response needed for protection against a given infectious agent. We have here tested fusion DNA vaccines which encode proteins that bivalently target influenza hemagglutinins (HA) to different surface molecules on antigen presenting cells (APC). We demonstrate that targeting to MHC class II molecules predominantly induced an antibody/Th2 response, whereas targeting to CCR1/3/5 predominantly induced a CD8+/Th1 T cell response. With respect to antibodies, the polarizing effect was even more pronounced upon intramuscular (i.m) delivery as compared to intradermal (i.d.) vaccination. Despite these differences in induced immune responses, both vaccines protected against a viral challenge with influenza H1N1. Substitution of HA with ovalbumin (OVA) demonstrated that polarization of immune responses, as a consequence of APC targeting specificity, could be extended to other antigens. Taken together, the results demonstrate that vaccination can be tailor-made to induce a particular phenotype of adaptive immune responses by specifically targeting different surface molecules on APCs. PMID:24244595

  13. Nuances in diet quality and quantity influence phenotypic dimorphism during honey bee (Apis mellifera) caste determination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrition intake during the larval stage of holometabolous insect’s influences and fuels growth throughout metamorphosis. In social insects, differences in larval nutrition can regulate a profound reproductive division of labor. Provisioning by nurse bees differs between worker-destined and queen-de...

  14. Membrane proteins in senescent erythrocytes.

    PubMed Central

    Suzuki, T; Dale, G L

    1989-01-01

    The examination of erythrocyte senescence has been facilitated by recent advances in techniques for the isolation of aged red cells. One of these methods, which uses biotinylated rabbit erythrocytes, has been used to examine the state of membrane proteins in effete cells. These aged red cells were found to have normal ratios of alpha-spectrin and beta-spectrin as well as normal levels of ankyrin. The observation concerning ankyrin is particularly important due to the sensitivity of this protein to proteolysis and the postulated action of proteinases in the aging process. The senescent erythrocytes were also found to have an altered ratio of bands 4.1a and 4.1b without any apparent change in the total level of 4.1. In addition, the analysis of the aged cell membranes did not show any large-molecular-mass aggregated protein at the origin of the SDS/polyacrylamide gels, indicating a lack of transglutaminase activity in the senescence process for rabbit erythrocytes. These results indicate that aging of the rabbit erythrocyte is not accompanied by gross proteolytic degradation or transglutaminase-catalysed cross-linking of membrane components. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:2522000

  15. [Sodium and calcium cation transport of erythrocytes in essential hypertension].

    PubMed

    Zhu, Z M; Song, K Q; Liu, G Y

    1989-08-01

    The sodium and calcium transport of erythrocyte and the influencing factors were studied in essential hypertensive (EH) subjects. The result showed that plasma endogenous digitalis-like compound (EDLC) increased and sodium pump depressed in some EH patients, but there were no parallel correlation between EDLC and sodium pump. The patients with normal sodium pump mainly showed their maximal Ca2+ pump activity and decreased calmodulin (CaM) content of erythrocyte. Thus there may be different types of ion transport defect in EH, and the abnormalities of these cation transports have an important role in the pathogenesis of EH. PMID:2560705

  16. Morphological Effects Induced In Vitro by Propranolol on Human Erythrocytes.

    PubMed

    Suwalsky, Mario; Zambrano, Pablo; Villena, Fernando; Manrique-Moreno, Marcela; Gallardo, María José; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz; Edwards, Ana María; Mennickent, Sigrid; Dukes, Nathan

    2015-08-01

    Despite the extended use and well-documented information, there are insufficient reports concerning the effects of propranolol on the structure and functions of cell membranes, particularly those of human erythrocytes. Aimed to better understand the molecular mechanisms of its interactions with cell membranes, human erythrocyte and molecular models of the red cell membrane were utilized. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of propranolol to perturb the multibilayer structures of DMPC and DMPE was evaluated by X-ray diffraction. Moreover, we took advantage of the capability of differential scanning calorimetry to detect the changes in the thermotropic phase behavior of lipid bilayers resulting from propranolol interaction with DMPC and DMPE multilamellar vesicles. In an attempt to further elucidate their effects on cell membranes, the present work also examined their influence on the morphology of intact human erythrocytes by means of defocusing and scanning electron microscopy. Results indicated that propranolol induced morphological changes to human erythrocytes and interacted in a concentration-dependent manner with phospholipid bilayer. PMID:25724773

  17. Abnormalities of the erythrocyte membrane.

    PubMed

    Gallagher, Patrick G

    2013-12-01

    Primary abnormalities of the erythrocyte membrane are characterized by clinical, laboratory, and genetic heterogeneity. Among this group, hereditary spherocytosis patients are more likely to experience symptomatic anemia. Treatment of hereditary spherocytosis with splenectomy is curative in most patients. Growing recognition of the long-term risks of splenectomy has led to re-evaluation of the role of splenectomy. Management guidelines acknowledge these considerations and recommend discussion between health care providers, patient, and family. The hereditary elliptocytosis syndromes are the most common primary disorders of erythrocyte membrane proteins. However, most elliptocytosis patients are asymptomatic and do not require therapy.

  18. Current status of erythrocyte substitutes.

    PubMed Central

    Biro, G. P.

    1983-01-01

    During the last two decades the search for alternatives to whole blood transfusions has led to promising developments in the field of erythrocyte substitutes. Hemoglobin solutions free of fragments of erythrocyte stroma and fluorocarbon emulsions are not blood-type-specific and appear likely to satisfy some proportion of our blood requirements. Both must be modified before becoming clinically useful. The oxygen affinity of the hemoglobin solution must be reduced and its intravascular persistence improved. Fluorocarbons cannot yet contribute significantly to the oxygen supply unless the patient breathes hyperbaric oxygen. Recent advances are leading to solutions for these problems. PMID:6344974

  19. Population density and phenotypic attributes influence the level of nematode parasitism in roe deer.

    PubMed

    Body, Guillaume; Ferté, Hubert; Gaillard, Jean-Michel; Delorme, Daniel; Klein, François; Gilot-Fromont, Emmanuelle

    2011-11-01

    The impact of parasites on population dynamics is well documented, but less is known on how host population density affects parasite spread. This relationship is difficult to assess because of confounding effects of social structure, population density, and environmental conditions that lead to biased among-population comparisons. Here, we analyzed the infestation by two groups of nematodes (gastro-intestinal (GI) strongyles and Trichuris) in the roe deer (Capreolus capreolus) population of Trois Fontaines (France) between 1997 and 2007. During this period, we experimentally manipulated population density through changes in removals. Using measures collected on 297 individuals, we quantified the impact of density on parasite spread after taking into account possible influences of date, age, sex, body mass, and weather conditions. The prevalence and abundance of eggs of both parasites in females were positively related to roe deer density, except Trichuris in adult females. We also found a negative relationship between parasitism and body mass, and strong age and sex-dependent patterns of parasitism. Prime-age adults were less often parasitized and had lower fecal egg counts than fawns or old individuals, and males were more heavily and more often infected than females. Trichuris parasites were not affected by weather, whereas GI strongyles were less present after dry and hot summers. In the range of observed densities, the observed effect of density likely involves a variation of the exposure rate, as opposed to variation in host susceptibility.

  20. Cyclin D3 coordinates the cell cycle during differentiation to regulate erythrocyte size and number.

    PubMed

    Sankaran, Vijay G; Ludwig, Leif S; Sicinska, Ewa; Xu, Jian; Bauer, Daniel E; Eng, Jennifer C; Patterson, Heide Christine; Metcalf, Ryan A; Natkunam, Yasodha; Orkin, Stuart H; Sicinski, Piotr; Lander, Eric S; Lodish, Harvey F

    2012-09-15

    Genome-wide association studies (GWASs) have identified a genetic variant of moderate effect size at 6p21.1 associated with erythrocyte traits in humans. We show that this variant affects an erythroid-specific enhancer of CCND3. A Ccnd3 knockout mouse phenocopies these erythroid phenotypes, with a dramatic increase in erythrocyte size and a concomitant decrease in erythrocyte number. By examining human and mouse primary erythroid cells, we demonstrate that the CCND3 gene product cyclin D3 regulates the number of cell divisions that erythroid precursors undergo during terminal differentiation, thereby controlling erythrocyte size and number. We illustrate how cell type-specific specialization can occur for general cell cycle components-a finding resulting from the biological follow-up of unbiased human genetic studies.

  1. A Demonstration of Erythrocyte Membrane Asymmetry.

    ERIC Educational Resources Information Center

    Pederson, Philip; And Others

    1985-01-01

    A three-period experiment was developed to help students visualize asymmetric distribution of proteins within membranes. It includes: (1) isolating erythrocyte membranes; (2) differential labeling of intact erythrocytes and isolated erythrocyte membranes with an impermeable fluorescent dye; and (3) separating proteins by polyacrylamide gel…

  2. Chick-Erythrocyte Nucleus Reactivation in Heterokaryons: Suppression by Inhibitors of Proteolytic Enzymes

    PubMed Central

    Darzynkiewicz, Zbigniew; Chelmicka-Szorc, Ewa; Arnason, Barry G. W.

    1974-01-01

    Reactivation of chick-erythrocyte nuclei in heterokaryons (obtained by Sendai virus-induced fusion of chick erythrocytes with HeLa cells) is suppressed by specific inhibitors of trypsin and trypsin-like enzymes. N-α-tosyl-L-lysyl-chloromethane and N-α-tosyl-L-arginine methylester inhibit erythrocyte nuclear enlargement and suppress RNA and DNA synthesis in nuclei of erythrocytes and HeLa cells in heterokaryons at concentrations that only minimally influence individual HeLa cells or HeLa homokaryons. Although other unknown mechanisms of action cannot be formally excluded, the data are interpreted as fitting best with an intracellular site of action of the protease inhibitors studied, and as suggesting a role for cellular proteases in reactivation of chick-erythrocyte nuclei in heterokaryons. PMID:4522779

  3. Influence of the bacterial phenotypes on the clinical manifestations in Klebsiella pneumoniae bacteremia patients: A retrospective cohort study.

    PubMed

    Togawa, Atsushi; Toh, Hiromi; Onozawa, Kyoko; Yoshimura, Michinobu; Tokushige, Chiemi; Shimono, Nobuyuki; Takata, Tohru; Tamura, Kazuo

    2015-07-01

    Ninety-four episodes of Klebsiella pneumoniae bloodstream infection were identified at a university hospital in Japan. After excluding extended-spectrum beta lactamase-producing strains, 83 blood isolates from these patients were assayed in terms of their bacterial phenotypes such as the mucoid and hypermucoviscosity phenotypes. Bacterial phenotypes were correlated with the patients' clinical manifestations. The hypermucoviscosity phenotype was significantly associated with septic shock at the onset of infections (odds ratio, 15.92; 95% confidence interval, 1.27-468.12), but was not associated with liver abscess formation. Mortality was determined by the presence of septic shock. RmpA gene was associated with the induction of the hypermucoviscosity phenotype. These results reveal unique roles of bacterial phenotypes on the patient's clinical condition in K. pneumoniae bacteremia.

  4. The cholesterol content of the erythrocyte membrane is an important determinant of phosphatidylserine exposure.

    PubMed

    van Zwieten, Rob; Bochem, Andrea E; Hilarius, Petra M; van Bruggen, Robin; Bergkamp, Ferry; Hovingh, G Kees; Verhoeven, Arthur J

    2012-12-01

    Maintenance of the asymmetric distribution of phospholipids across the plasma membrane is a prerequisite for the survival of erythrocytes. Various stimuli have been shown to induce scrambling of phospholipids and thereby exposure of phosphatidylserine (PS). In two types of patients, both with aberrant plasma cholesterol levels, we observed an aberrant PS exposure in erythrocytes upon stimulation. We investigated the effect of high and low levels of cholesterol on the ATP-dependent flippase, which maintains phospholipid asymmetry, and the ATP-independent scrambling activity, which breaks down phospholipid asymmetry. We analyzed erythrocytes of a patient with spur cell anemia, characterized by elevated plasma cholesterol, and the erythrocytes of Tangier disease patients with very low levels of plasma cholesterol. In normal erythrocytes, loaded with cholesterol or depleted of cholesterol in vitro, the same analyses were performed. Changes in the cholesterol/phospholipid ratio of erythrocytes had marked effects on PS exposure upon cell activation. Excess cholesterol profoundly inhibited PS exposure, whereas cholesterol depletion led to increased PS exposure. The activity of the ATP-dependent flippase was not changed, suggesting a major influence of cholesterol on the outward translocation of PS. The effects of cholesterol were not accompanied by eminent changes in cytoskeletal and membrane proteins. These findings emphasize the importance of cholesterol exchange between circulating plasma and the erythrocyte membrane as determinant for phosphatidylserine exposure in erythrocytes.

  5. Interaction of major genes predisposing to hepatocellular carcinoma with genes encoding signal transduction pathways influences tumor phenotype and prognosis

    PubMed Central

    Feo, Francesco; Frau, Maddalena; Pascale, Rosa Maria

    2008-01-01

    Studies on rodents and humans demonstrate an inherited predisposition to hepatocellular carcinoma (HCC). Analysis of the molecular alterations involved in the acquisition of a phenotype resistant or susceptible to hepatocarcinogenesis showed a deregulation of G1 and S phases in HCC of genetically susceptible F344 rats and a G1-S block in lesions of resistant Brown norway (BN) rats. Unrestrained extracellular signal-regulated kinase (ERK) activity linked to proteasomal degradation of dual-specificity phosphatase 1 (DUSP1), a specific ERK inhibitor, by the CKS1-SKP2 ubiquitin ligase complex occurs in more aggressive HCC of F344 rats and humans. This mechanism is less active in HCC of BN rats and human HCC with better prognosis. Upregulation of iNos cross-talk with IKK/NF-κB and RAS/ERK pathways occurs in rodent liver lesions at higher levels in the most aggressive models represented by HCC of F344 rats and c-Myc-TGF-α transgenic mice. iNOS, IKK/NF-κB, and RAS/ERK upregulation is highest in human HCC with a poorer prognosis and positively correlates with tumor proliferation, genomic instability and microvascularization, and negatively with apoptosis. Thus, cell cycle regulation and the activity of signal transduction pathways seem to be modulated by HCC modifier genes, and differences in their efficiency influence the susceptibility to hepatocarcinogenesis and probably the prognosis of human HCC. PMID:19034960

  6. The Genomic Analysis of Erythrocyte microRNA Expression in Sickle Cell Diseases

    PubMed Central

    Chen, Shao-Yin; Wang, Yulei; Telen, Marilyn J.; Chi, Jen-Tsan

    2008-01-01

    Background Since mature erythrocytes are terminally differentiated cells without nuclei and organelles, it is commonly thought that they do not contain nucleic acids. In this study, we have re-examined this issue by analyzing the transcriptome of a purified population of human mature erythrocytes from individuals with normal hemoglobin (HbAA) and homozygous sickle cell disease (HbSS). Methods and Findings Using a combination of microarray analysis, real-time RT-PCR and Northern blots, we found that mature erythrocytes, while lacking ribosomal and large-sized RNAs, contain abundant and diverse microRNAs. MicroRNA expression of erythrocytes was different from that of reticulocytes and leukocytes, and contributed the majority of the microRNA expression in whole blood. When we used microRNA microarrays to analyze erythrocytes from HbAA and HbSS individuals, we noted a dramatic difference in their microRNA expression pattern. We found that miR-320 played an important role for the down-regulation of its target gene, CD71 during reticulocyte terminal differentiation. Further investigation revealed that poor expression of miR-320 in HbSS cells was associated with their defective downregulation CD71 during terminal differentiation. Conclusions In summary, we have discovered significant microRNA expression in human mature erythrocytes, which is dramatically altered in HbSS erythrocytes and their defect in terminal differentiation. Thus, the global analysis of microRNA expression in circulating erythrocytes can provide mechanistic insights into the disease phenotypes of erythrocyte diseases. PMID:18523662

  7. Influence of a nucleotide oligomerization domain 1 (NOD1) polymorphism and NOD2 mutant alleles on Crohn's disease phenotype

    PubMed Central

    Cantó, Elisabet; Ricart, Elena; Busquets, David; Monfort, David; García-Planella, Esther; González, Dolors; Balanzó, Joaquim; Rodríguez-Sánchez, José L; Vidal, Sílvia

    2007-01-01

    AIM: To examine genetic variation of nucleotide oligomerization domain 1 (NOD1) and NOD2, their respective influences on Crohn's disease phenotype and gene-gene interactions. METHODS: (ND1+32656*1) NOD1 polymorphism and SNP8, SNP12 and SNP13 of NOD2 were analyzed in 97 patients and 50 controls. NOD2 variants were determined by reaction restriction fragment length polymorphism analysis. NOD1 genotyping and NOD2 variant confirmation were performed by specific amplification and sequencing. RESULTS: The distribution of NOD1 polymorphism in patients was different from controls (P = 0.045) and not altered by existence of NOD2 mutations. In this cohort, 30.92% patients and 6% controls carried at least one NOD2 variant (P < 0.001) with R702W being the most frequent variant. Presence of at least one NOD2 mutation was inversely associated with colon involvement (9.09% with colon vs 36.4% with ileal or ileocolonic involvement, P = 0.04) and indicative of risk of penetrating disease (52.63% with penetrating vs 25.64% with non-penetrating or stricturing behavior, P = 0.02). L1007finsC and double NOD2 mutation conferred the highest risk for severity of disease (26.3% with penetrating disease vs 3.8% with non-penetrating or stricturing behavior presented L1007finsC, P = 0.01 and 21.0% with penetrating disease vs 2.5% with non-penentrating or stricturing behavior carried double NOD2 mutation, P = 0.007). Exclusion of patients with NOD2 mutations from phenotype/NOD1-genotype analysis revealed higher prevalence of *1*1 genotype in groups of younger age at onset and colonic location. CONCLUSION: This study suggests population differences in the inheritance of risk NOD1 polymorphism and NOD2 mutations. Although no interaction between NOD1-NOD2 was noticed, a relationship between disease location and Nod-like receptor molecules was established. PMID:17907287

  8. Of mothers and myelin: Aberrant myelination phenotypes in mouse model of Angelman Syndrome are dependent on maternal and dietary influences

    PubMed Central

    Grier, Mark D.; Carson, Robert P.; Lagrange, Andre H.

    2015-01-01

    Angelman Syndrome (AS) is a neurodevelopmental disorder characterized by a number of neurological problems, including developmental delay, movement disorders and epilepsy. AS results from the loss of UBE3A (an imprinted gene) expressed from the maternal chromosome in neurons. Given the ubiquitous expression of Ube3a and the devastating nature of AS, the role of environmental and maternal effects has been largely ignored. Severe ataxia, anxiety-like behaviors and learning deficits are well-documented in patients and AS mice. More recently, clinical imaging studies of AS patients suggest myelination may be delayed or reduced. Utilizing a mouse model of AS, we found disrupted expression of cortical myelin proteins, the magnitude of which is influenced by maternal status, in that the aberrant myelination in the AS pups of AS affected mothers were more pronounced than those seen in AS pups raised by unaffected (Ube3a (m+/p-)) Carrier mothers. Furthermore, feeding the breeding mothers a higher fat (11% vs 5%) diet normalizes these myelin defects. These effects are not limited to myelin proteins. Since AS mice have abnormal stress responses, including altered glucocorticoid receptor (GR) expression, we measured GR expression in pups from Carrier and affected AS mothers. AS pups had higher GR expression than their WT littermates. However, we also found an effect of maternal status, with reduced GR levels in pups from affected mothers compared to genotypically identical pups raised by unaffected Carrier mothers. Taken together, our findings suggest that the phenotypes observed in AS mice may be modulated by factors independent of Ube3a genotype. PMID:26028516

  9. Of mothers and myelin: Aberrant myelination phenotypes in mouse model of Angelman syndrome are dependent on maternal and dietary influences.

    PubMed

    Grier, Mark D; Carson, Robert P; Lagrange, Andre H

    2015-09-15

    Angelman syndrome (AS) is a neurodevelopmental disorder characterized by a number of neurological problems, including developmental delay, movement disorders, and epilepsy. AS results from the loss of UBE3A (an imprinted gene) expressed from the maternal chromosome in neurons. Given the ubiquitous expression of Ube3a and the devastating nature of AS, the role of environmental and maternal effects has been largely ignored. Severe ataxia, anxiety-like behaviors and learning deficits are well-documented in patients and AS mice. More recently, clinical imaging studies of AS patients suggest myelination may be delayed or reduced. Utilizing a mouse model of AS, we found disrupted expression of cortical myelin proteins, the magnitude of which is influenced by maternal status, in that the aberrant myelination in the AS pups of AS affected mothers were more pronounced than those seen in AS pups raised by unaffected (Ube3a (m+/p-)) Carrier mothers. Furthermore, feeding the breeding mothers a higher fat (11% vs 5%) diet normalizes these myelin defects. These effects are not limited to myelin proteins. Since AS mice have abnormal stress responses, including altered glucocorticoid receptor (GR) expression, we measured GR expression in pups from Carrier and affected AS mothers. AS pups had higher GR expression than their WT littermates. However, we also found an effect of maternal status, with reduced GR levels in pups from affected mothers compared to genotypically identical pups raised by unaffected Carrier mothers. Taken together, our findings suggest that the phenotypes observed in AS mice may be modulated by factors independent of Ube3a genotype. PMID:26028516

  10. Effect of 8-alkylberberine homologues on erythrocyte membrane.

    PubMed

    Yong, Yang; Ye, Xiao-Li; Zhang, Bao-Shun; Li, Xue-Gang

    2011-05-01

    8-alkylberberine homologues (Ber-C8-n, where n indicates carbon atom number of gaseous normal alkyl at 8 position, n = 0, 2, 4, 6, 8, 10, 12, or 16) were synthesized and their effects on the hemolysis of rabbit erythrocyte, the fluidity of membrane and the fluorescence of membrane protein were investigated by fluorescence analysis technique. Ber-C8-n with mediate length alkyl (4 < n < 10) exhibited obvious hemolysis effect on rabbit erythrocyte when their concentration exceed 1.25 x10(-4) mol/L, and Ber-C8-8 displayed the highest hemolysis effect among all tested homologues. All of Ber-C8-n influenced the fluidity of erythrocyte membrane to different extents, which exhibited an obvious dose-effect relationship. The effect of Ber-C8-n on fluidity increased as the length of alkyl chain was elongated and decreased gradually when the alkyl carbon atoms exceeded 8. The fluorescence of erythrocyte membrane protein was quenched by Ber-C8-n, which showed a similar changing tendency on membrane fluidity. Experiments in vitro suggested that disturbing effects of Ber-C8-n on the conformation and function of membrane protein leaded to the changes of membrane fluidity and stability, and then the membrane was broken down.

  11. Can erythrocytes release biologically active NO?

    PubMed

    Benz, Peter M; Fleming, Ingrid

    2016-01-01

    Under physiological conditions, endothelial cells and the endothelial nitric oxide (NO) synthase (eNOS) are the main source of NO in the cardiovascular system. However, several other cell types have also been implicated in the NO-dependent regulation of cell function, including erythrocytes. NO derived from red blood cells has been proposed to regulate erythrocyte membrane fluidity, inhibit platelet activation and induce vasodilation in hypoxic areas, but these proposals are highly controversial. In the current issue of Cell Communication and Signaling, an elegant study by Gambaryan et al., assayed NO production by erythrocytes by monitoring the activation of the platelet intracellular NO receptor, soluble guanylyl cyclase, and its downstream kinase protein kinase G. After systematically testing different combinations of erythrocyte/platelet suspensions, the authors found no evidence for platelet soluble guanylyl cyclase/protein kinase G activation by erythrocytes and conclude that erythrocytes do not release biologically active NO to inhibit platelet activation. PMID:27639852

  12. Erythrocyte Lysis and Xenopus laevis Oocyte Rupture by Recombinant Plasmodium falciparum Hemolysin III

    PubMed Central

    Moonah, Shannon; Sanders, Natalie G.; Persichetti, Jason K.

    2014-01-01

    Malaria kills more than 1 million people per year worldwide, with severe malaria anemia accounting for the majority of the deaths. Malaria anemia is multifactorial in etiology, including infected erythrocyte destruction and decrease in erythrocyte production, as well as destruction or clearance of noninfected erythrocytes. We identified a panspecies Plasmodium hemolysin type III related to bacterial hemolysins. The identification of a hemolysin III homologue in Plasmodium suggests a potential role in host erythrocyte lysis. Here, we report the first characterization of Plasmodium falciparum hemolysin III, showing that the soluble recombinant P. falciparum hemolysin III is a pore-forming protein capable of lysing human erythrocytes in a dose-, time-, and temperature-dependent fashion. The recombinant P. falciparum hemolysin III-induced hemolysis was partially inhibited by glibenclamide, a known channel antagonist. Studies with polyethylene glycol molecules of different molecular weights indicated a pore size of approximately 3.2 nm. Heterologous expression of recombinant P. falciparum hemolysin III in Xenopus oocytes demonstrated early hypotonic lysis similar to that of the pore-forming aquaporin control. Live fluorescence microscopy localized transfected recombinant green fluorescent protein (GFP)-tagged P. falciparum hemolysin III to the essential digestive vacuole of the P. falciparum parasite. These transfected trophozoites also possessed a swollen digestive vacuole phenotype. Native Plasmodium hemolysin III in the digestive vacuole may contribute to lysis of the parasitophorous vacuole membrane derived from the host erythrocyte. After merozoite egress from infected erythrocytes, remnant P. falciparum hemolysin III released from digestive vacuoles could potentially contribute to lysis of uninfected erythrocytes to contribute to severe life-threatening anemia. PMID:25148832

  13. Erythrocyte lysis and Xenopus laevis oocyte rupture by recombinant Plasmodium falciparum hemolysin III.

    PubMed

    Moonah, Shannon; Sanders, Natalie G; Persichetti, Jason K; Sullivan, David J

    2014-10-01

    Malaria kills more than 1 million people per year worldwide, with severe malaria anemia accounting for the majority of the deaths. Malaria anemia is multifactorial in etiology, including infected erythrocyte destruction and decrease in erythrocyte production, as well as destruction or clearance of noninfected erythrocytes. We identified a panspecies Plasmodium hemolysin type III related to bacterial hemolysins. The identification of a hemolysin III homologue in Plasmodium suggests a potential role in host erythrocyte lysis. Here, we report the first characterization of Plasmodium falciparum hemolysin III, showing that the soluble recombinant P. falciparum hemolysin III is a pore-forming protein capable of lysing human erythrocytes in a dose-, time-, and temperature-dependent fashion. The recombinant P. falciparum hemolysin III-induced hemolysis was partially inhibited by glibenclamide, a known channel antagonist. Studies with polyethylene glycol molecules of different molecular weights indicated a pore size of approximately 3.2 nm. Heterologous expression of recombinant P. falciparum hemolysin III in Xenopus oocytes demonstrated early hypotonic lysis similar to that of the pore-forming aquaporin control. Live fluorescence microscopy localized transfected recombinant green fluorescent protein (GFP)-tagged P. falciparum hemolysin III to the essential digestive vacuole of the P. falciparum parasite. These transfected trophozoites also possessed a swollen digestive vacuole phenotype. Native Plasmodium hemolysin III in the digestive vacuole may contribute to lysis of the parasitophorous vacuole membrane derived from the host erythrocyte. After merozoite egress from infected erythrocytes, remnant P. falciparum hemolysin III released from digestive vacuoles could potentially contribute to lysis of uninfected erythrocytes to contribute to severe life-threatening anemia.

  14. Optical tweezer for probing erythrocyte membrane deformability

    NASA Astrophysics Data System (ADS)

    Khan, Manas; Soni, Harsh; Sood, A. K.

    2009-12-01

    We report that the average rotation speed of optically trapped crenated erythrocytes is direct signature of their membrane deformability. When placed in hypertonic buffer, discocytic erythrocytes are subjected to crenation. The deformation of cells brings in chirality and asymmetry in shape that makes them rotate under the scattering force of a linearly polarized optical trap. A change in the deformability of the erythrocytes, due to any internal or environmental factor, affects the rotation speed of the trapped crenated cells. Here we show how the increment in erythrocyte membrane rigidity with adsorption of Ca++ ions can be exhibited through this approach.

  15. The effect of leptin on Na(+)-H(+) antiport (NHE 1) activity of obese and normal subjects erythrocytes.

    PubMed

    Konstantinou-Tegou, A; Kaloyianni, M; Bourikas, D; Koliakos, G

    2001-10-25

    Obesity is currently considered as a chronic metabolic disease, associated with a high risk of cardiovascular complications. Leptin, an adipocyte-derived hormone has a variety target cells influencing a wide range of processes. Possible counteractions of hyperleptinaemia are currently investigated. The Na(+)-H(+) exchanger (NHE 1) is involved in multiple cellular functions and its activation has been related to hypertension and obesity. NHE 1 is present on erythrocytes and can be stimulated by various hormones. Erythrocytes have on their surface a variety of receptors with mostly unknown function. In the present paper, the effect of leptin on erythrocytes NHE 1 activity has been investigated. For this reason, the intracellular pH and sodium influxes were measured before and after addition of leptin in erythrocyte suspensions from normal and obese individuals. Amiloride, a specific NHE 1 inhibitor, and staurosporine a protein kinase C inhibitor were used to inhibit erythrocyte NHE 1. For the binding study leptin was labeled with fluorescein isothiocyanate (FITC) and the binding on erythrocytes was estimated by Scatchard analysis. NHE 1 activity increased in the presence of leptin but significantly less in the obese than in the control group. Furthermore the concentrations of leptin binding sites on the surface of erythrocytes were lower in erythrocytes drawn from obese individuals than in erythrocytes drawn from normal subjects. Since NHE 1 activity has been associated with insulin resistance and hypertension, the activation of this antiport by leptin may represent a link between adipose tissue hypertrophy and cardiovascular complications of obesity.

  16. Micro-Raman spectroscopy study of the effect of Mid-Ultraviolet radiation on erythrocyte membrane.

    PubMed

    Li, N; Li, S X; Guo, Z Y; Zhuang, Z F; Li, R; Xiong, K; Chen, S J; Liu, S H

    2012-07-01

    Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane.

  17. Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia.

    PubMed

    Wadhwani, Nisha S; Narang, Ankita S; Mehendale, Savita S; Wagh, Girija N; Gupte, Sanjay A; Joshi, Sadhana R

    2016-01-01

    The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16-20th weeks, 26-30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α-linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n-6 fatty acids were higher (p < 0.05) at 16-20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n-3, 22:6n-3, 24:1n-9, MUFA, and total n-3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n-3 and 24:1n-9 at 16-20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.

  18. Parasite Sequestration in Plasmodium falciparum Malaria: Spleen and Antibody Modulation of Cytoadherence of Infected Erythrocytes

    NASA Astrophysics Data System (ADS)

    David, Peter H.; Hommel, Marcel; Miller, Louis H.; Udeinya, Iroka J.; Oligino, Lynette D.

    1983-08-01

    Sequestration, the adherence of infected erythrocytes containing late developmental stages of the parasite (trophozoites and schizonts) to the endothelium of capillaries and venules, is characteristic of Plasmodium falciparum infections. We have studied two host factors, the spleen and antibody, that influence sequestration of P. falciparum in the squirrel monkey. Sequestration of trophozoite/schizont-infected erythrocytes that occurs in intact animals is reduced in splenectomized animals; in vitro, when infected blood is incubated with monolayers of human melanoma cells, trophozoite/schizont-infected erythrocytes from intact animals but not from splenectomized animals bind to the melanoma cells. The switch in cytoadherence characteristics of the infected erythrocytes from nonbinding to binding occurs with a cloned parasite. Immune serum can inhibit and reverse in vitro binding to melanoma cells of infected erythrocytes from intact animals. Similarly, antibody can reverse in vivo sequestration as shown by the appearance of trophozoite/schizont-infected erythrocytes in the peripheral blood of an intact animal after inoculation with immune serum. These results indicate that the spleen modulates the expression of parasite alterations of the infected erythrocyte membrane responsible for sequestration and suggest that the prevention and reversal of sequestration could be one of the effector mechanisms involved in antibody-mediated protection against P. falciparum malaria.

  19. Lactobacillus rhamnosus GG supplementation during critical windows of gestation influences immune phenotype in Swiss albino mice offspring.

    PubMed

    Himaja, N; Hemalatha, R; Narendra Babu, K; Shujauddin, M

    2016-01-01

    Probiotic supplementation during critical windows of gestation might have a significant influence on the infant's immune phenotype. Swiss albino mice (F0 generation) aged 31 days were supplemented orally with probiotic Lactobacillus rhamnosus GG (LGG); and the supplementation was continued throughout mating, gestation and lactation. The pups (F1 generation) born to them were separated post weaning and received either the same probiotic supplementation as their mothers or were denied supplementation postnatally. Neutrophil phagocytic ability, splenocyte proliferation, immunoglobulins and cytokines were determined in both F0 and F1 pups. In addition, antibody response against hepatitis-B surface antigen (HBsAg) was determined in F1 pups. Probiotic supplementation had no effect on the neutrophil phagocytic ability and splenocyte proliferation index. The serum immunoglobulin G (IgG) and secretory IgA (s-IgA) among the probiotic supplemented group of F0 generation were significantly (P<0.05) higher compared to the controls. Similarly, the mean concentration of interleukin (IL)-10, IL-17 and interferon gamma (IFN-γ) among F0 probiotic group were significantly higher (P<0.05) compared to the control. Prenatal and postnatal probiotic supplementation in F1 pups led to similar results as F0 dams. Prenatal probiotic supplementation in F1 pups led to significantly (P<0.05) higher serum IgG (55.15 ± 1.35 ng/ml) and intestinal s-IgA (77.9 ± 2.86 ng/mg protein) concentration when compared to the control. Similarly, IFN-γ concentration increased (P<0.05) with prenatal probiotic supplementation compared to the control. However, IL-10 and IL-17 concentrations of prenatal probiotic supplemented F1 pups were comparable to the control. As for the antibody response to HBsAg, prenatal probiotic supplementation led to enhanced HBsAg antibody response (471.4 ± 3.97 U/ml) compared to the control. LGG affected the immune regulation and immune responses favourably in mothers and

  20. Acetylsalicylic acid (aspirin) and salicylic acid interaction with the human erythrocyte membrane bilayer induce in vitro changes in the morphology of erythrocytes.

    PubMed

    Suwalsky, Mario; Belmar, Jessica; Villena, Fernando; Gallardo, María José; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2013-11-01

    Despite the well-documented information, there are insufficient reports concerning the effects of salicylate compounds on the structure and functions of cell membranes, particularly those of human erythrocytes. With the aim to better understand the molecular mechanisms of the interaction of acetylsalicylic acid (ASA) and salicylic acid (SA) with cell membranes, human erythrocyte membranes and molecular models were utilized. These consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of ASA and SA to perturb the multibilayer structures of DMPC and DMPE was evaluated by X-ray diffraction while DMPC unilamellar vesicles (LUV) were studied by fluorescence spectroscopy. Moreover, we took advantage of the capability of differential scanning calorimetry (DSC) to detect the changes in the thermotropic phase behavior of lipid bilayers resulting from ASA and SA interaction with PC and PE molecules. In an attempt to further elucidate their effects on cell membranes, the present work also examined their influence on the morphology of intact human erythrocytes by means of defocusing and scanning electron microscopy, while isolated unsealed human erythrocyte membranes (IUM) were studied by fluorescence spectroscopy. Results indicated that both salicylates interact with human erythrocytes and their molecular models in a concentration-dependent manner perturbing their bilayer structures. PMID:24055635

  1. Acetylsalicylic acid (aspirin) and salicylic acid interaction with the human erythrocyte membrane bilayer induce in vitro changes in the morphology of erythrocytes.

    PubMed

    Suwalsky, Mario; Belmar, Jessica; Villena, Fernando; Gallardo, María José; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2013-11-01

    Despite the well-documented information, there are insufficient reports concerning the effects of salicylate compounds on the structure and functions of cell membranes, particularly those of human erythrocytes. With the aim to better understand the molecular mechanisms of the interaction of acetylsalicylic acid (ASA) and salicylic acid (SA) with cell membranes, human erythrocyte membranes and molecular models were utilized. These consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of ASA and SA to perturb the multibilayer structures of DMPC and DMPE was evaluated by X-ray diffraction while DMPC unilamellar vesicles (LUV) were studied by fluorescence spectroscopy. Moreover, we took advantage of the capability of differential scanning calorimetry (DSC) to detect the changes in the thermotropic phase behavior of lipid bilayers resulting from ASA and SA interaction with PC and PE molecules. In an attempt to further elucidate their effects on cell membranes, the present work also examined their influence on the morphology of intact human erythrocytes by means of defocusing and scanning electron microscopy, while isolated unsealed human erythrocyte membranes (IUM) were studied by fluorescence spectroscopy. Results indicated that both salicylates interact with human erythrocytes and their molecular models in a concentration-dependent manner perturbing their bilayer structures.

  2. Signal transduction pathways in erythrocyte nitric oxide metabolism under high fibrinogen levels

    NASA Astrophysics Data System (ADS)

    Saldanha, Carlota; Freitas, T.; Lopez de Almeida, J. P.; Silva-Herdade, A.

    2014-05-01

    Previous studies show that the fibrinogen molecule modulates the metabolism of nitric oxide (NO) in erythrocyte. The in vitro induced hiperfibrinogenemia interferes in the metabolism of the NO in the erythrocyte in dependence of the phosphorylation degree of the band 3. The soluble form of fibrinogen binds into CD47 protein present in the erythrocyte membrane. The soluble thrombomodulin is an inflammatory marker that binds to the erythrocyte CD47 in a site with a sequence peptide known as 4N1K. A study done in vitro shows that when hiperfibrinogenemia was induced in the presence of the peptide 4N1K agonist of CD47 it were observed variations in the efflux of NO from erythrocyte and an increase in the concentrations of GSNO, peroxinitrite, nitrite and nitrate of the erythrocytes. The aim of this work was to study the influence of the peptide 4N1K, on the metabolism of NO in the erythrocyte under high fibrinogen concentration and in the presence of inhibitors of the status of phosphorylation of protein band 3. In this in vitro study, whole blood samples were harvested from healthy subjects and NO, peroxynitrite, nitrite, nitrate and S-nitro-glutathione (GSNO) were determined in presence of 4N1K, calpeptine, Syk inhibitor and under high fibrinogen concentrations. The results obtained in erythrocytes under high fibrinogen levels when 4N1K is present with the Syk inhibitor or with calpeptine, showed in relation to the control samples increased significant concentrations of efflux of NO and of peroxynitrite, nitrite, nitrate and GSNO. In conclusion it was verified that in the in vitro model of hiperfibrinogenemia the peptide 4N1K, agonist of CD47, induces mobilization of NO in the erythrocyte in dependence of the status of phosphorylation of protein band 3.

  3. Induction of Suicidal Erythrocyte Death by Cantharidin

    PubMed Central

    Alzoubi, Kousi; Egler, Jasmin; Briglia, Marilena; Fazio, Antonella; Faggio, Caterina; Lang, Florian

    2015-01-01

    The natural phosphoprotein phosphatase inhibitor cantharidin, primarily used for topical treatment of warts, has later been shown to trigger tumor cell apoptosis and is thus considered for the treatment of malignancy. Similar to apoptosis of tumor cells, erythrocytes may undergo eryptosis, a suicidal cell death characterized by cell shrinkage and translocation of cell membrane phosphatidylserine to the erythrocyte surface. Signaling of eryptosis includes increase of cytosolic Ca2+-activity ([Ca2+]i), ceramide, oxidative stress and dysregulation of several kinases. Phosphatidylserine abundance at the erythrocyte surface was quantified utilizing annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ceramide from antibody binding, and reactive oxidant species (ROS) from 2′,7′-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence. A 48 h treatment of human erythrocytes with cantharidin significantly increased the percentage of annexin-V-binding cells (≥10 μg/mL), significantly decreased forward scatter (≥25 μg/mL), significantly increased [Ca2+]i (≥25 μg/mL), but did not significantly modify ceramide abundance or ROS. The up-regulation of annexin-V-binding following cantharidin treatment was not significantly blunted by removal of extracellular Ca2+ but was abolished by kinase inhibitor staurosporine (1 μM) and slightly decreased by p38 inhibitor skepinone (2 μM). Exposure of erythrocytes to cantharidin triggers suicidal erythrocyte death with erythrocyte shrinkage and erythrocyte membrane scrambling, an effect sensitive to kinase inhibitors staurosporine and skepinone. PMID:26226001

  4. Induction of Suicidal Erythrocyte Death by Cantharidin.

    PubMed

    Alzoubi, Kousi; Egler, Jasmin; Briglia, Marilena; Fazio, Antonella; Faggio, Caterina; Lang, Florian

    2015-08-01

    The natural phosphoprotein phosphatase inhibitor cantharidin, primarily used for topical treatment of warts, has later been shown to trigger tumor cell apoptosis and is thus considered for the treatment of malignancy. Similar to apoptosis of tumor cells, erythrocytes may undergo eryptosis, a suicidal cell death characterized by cell shrinkage and translocation of cell membrane phosphatidylserine to the erythrocyte surface. Signaling of eryptosis includes increase of cytosolic Ca2+-activity ([Ca2+]i), ceramide, oxidative stress and dysregulation of several kinases. Phosphatidylserine abundance at the erythrocyte surface was quantified utilizing annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ceramide from antibody binding, and reactive oxidant species (ROS) from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescence. A 48 h treatment of human erythrocytes with cantharidin significantly increased the percentage of annexin-V-binding cells (≥10 mg/mL), significantly decreased forward scatter (≥25 mg/mL), significantly increased [Ca2+]i (≥25 mg/mL), but did not significantly modify ceramide abundance or ROS. The up-regulation of annexin-V-binding following cantharidin treatment was not significantly blunted by removal of extracellular Ca2+ but was abolished by kinase inhibitor staurosporine (1 mM) and slightly decreased by p38 inhibitor skepinone (2 mM). Exposure of erythrocytes to cantharidin triggers suicidal erythrocyte death with erythrocyte shrinkage and erythrocyte membrane scrambling, an effect sensitive to kinase inhibitors staurosporine and skepinone. PMID:26226001

  5. Interactions of the antiviral and antiparkinson agent amantadine with lipid membranes and human erythrocytes.

    PubMed

    Suwalsky, Mario; Jemiola-Rzeminska, Malgorzata; Altamirano, Mariella; Villena, Fernando; Dukes, Nathan; Strzalka, Kazimierz

    2015-07-01

    Aimed to better understand the molecular mechanisms of its interactions with cell membranes, human erythrocyte and molecular models of the red cell membrane were utilized. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of amantadine to perturb the bilayer structures of DMPC and DMPE was evaluated by X-ray diffraction, fluorescence spectroscopy and differential scanning calorimetry (DSC). In an attempt to further elucidate its effects on cell membranes, the present work also examined amantadine influence on the morphology of intact human erythrocytes by means of scanning electron microscopy (SEM). Results indicated that amantadine induced morphological changes to human erythrocytes and interacted in a concentration-dependent manner with DMPC bilayers in contrast to DMPE that was hardly affected by the presence of the drug. PMID:25899993

  6. Epigenetic changes in bone marrow progenitor cells influence the inflammatory phenotype and alter wound healing in type 2 diabetes.

    PubMed

    Gallagher, Katherine A; Joshi, Amrita; Carson, William F; Schaller, Matthew; Allen, Ronald; Mukerjee, Sumanta; Kittan, Nico; Feldman, Eva L; Henke, Peter K; Hogaboam, Cory; Burant, Charles F; Kunkel, Steven L

    2015-04-01

    Classically activated (M1) macrophages are known to play a role in the development of chronic inflammation associated with impaired wound healing in type 2 diabetes (T2D); however, the mechanism responsible for the dominant proinflammatory (M1) macrophage phenotype in T2D wounds is unknown. Since epigenetic enzymes can direct macrophage phenotypes, we assessed the role of histone methylation in bone marrow (BM) stem/progenitor cells in the programming of macrophages toward a proinflammatory phenotype. We have found that a repressive histone methylation mark, H3K27me3, is decreased at the promoter of the IL-12 gene in BM progenitors and this epigenetic signature is passed down to wound macrophages in a murine model of glucose intolerance (diet-induced obese). These epigenetically "preprogrammed" macrophages result in poised macrophages in peripheral tissue and negatively impact wound repair. We found that in diabetic conditions the H3K27 demethylase Jmjd3 drives IL-12 production in macrophages and that IL-12 production can be modulated by inhibiting Jmjd3. Using human T2D tissue and murine models, we have identified a previously unrecognized mechanism by which macrophages are programmed toward a proinflammatory phenotype, establishing a pattern of unrestrained inflammation associated with nonhealing wounds. Hence, histone demethylase inhibitor-based therapy may represent a novel treatment option for diabetic wounds.

  7. Epigenetic Changes in Bone Marrow Progenitor Cells Influence the Inflammatory Phenotype and Alter Wound Healing in Type 2 Diabetes

    PubMed Central

    Joshi, Amrita; Carson, William F.; Schaller, Matthew; Allen, Ronald; Mukerjee, Sumanta; Kittan, Nico; Feldman, Eva L.; Henke, Peter K.; Hogaboam, Cory; Burant, Charles F.; Kunkel, Steven L.

    2015-01-01

    Classically activated (M1) macrophages are known to play a role in the development of chronic inflammation associated with impaired wound healing in type 2 diabetes (T2D); however, the mechanism responsible for the dominant proinflammatory (M1) macrophage phenotype in T2D wounds is unknown. Since epigenetic enzymes can direct macrophage phenotypes, we assessed the role of histone methylation in bone marrow (BM) stem/progenitor cells in the programming of macrophages toward a proinflammatory phenotype. We have found that a repressive histone methylation mark, H3K27me3, is decreased at the promoter of the IL-12 gene in BM progenitors and this epigenetic signature is passed down to wound macrophages in a murine model of glucose intolerance (diet-induced obese). These epigenetically “preprogrammed” macrophages result in poised macrophages in peripheral tissue and negatively impact wound repair. We found that in diabetic conditions the H3K27 demethylase Jmjd3 drives IL-12 production in macrophages and that IL-12 production can be modulated by inhibiting Jmjd3. Using human T2D tissue and murine models, we have identified a previously unrecognized mechanism by which macrophages are programmed toward a proinflammatory phenotype, establishing a pattern of unrestrained inflammation associated with nonhealing wounds. Hence, histone demethylase inhibitor–based therapy may represent a novel treatment option for diabetic wounds. PMID:25368099

  8. Haptoglobin phenotype predicts the development of focal and global cerebral vasospasm and may influence outcomes after aneurysmal subarachnoid hemorrhage.

    PubMed

    Leclerc, Jenna L; Blackburn, Spiros; Neal, Dan; Mendez, Nicholas V; Wharton, Jeffrey A; Waters, Michael F; Doré, Sylvain

    2015-01-27

    Cerebral vasospasm (CV) and the resulting delayed cerebral ischemia (DCI) significantly contribute to poor outcomes following aneurysmal subarachnoid hemorrhage (aSAH). Free hemoglobin (Hb) within the subarachnoid space has been implicated in the pathogenesis of CV. Haptoglobin (Hp) binds free pro-oxidant Hb, thereby modulating its harmful effects. Humans can be of three Hp phenotypes: Hp1-1, Hp2-1, or Hp2-2. In several disease states, the Hp2-2 protein has been associated with reduced ability to protect against toxic free Hb. We hypothesized that individuals with the Hp2-2 phenotype would have more CV, DCI, mortality, and worse functional outcomes after aSAH. In a sample of 74 aSAH patients, Hp2-2 phenotype was significantly associated with increased focal moderate (P = 0.014) and severe (P = 0.008) CV and more global CV (P = 0.014) after controlling for covariates. Strong trends toward increased mortality (P = 0.079) and worse functional outcomes were seen for the Hp2-2 patients with modified Rankin scale at 6 wk (P = 0.076) and at 1 y (P = 0.051) and with Glasgow Outcome Scale Extended at discharge (P = 0.091) and at 1 y (P = 0.055). In conclusion, Hp2-2 phenotype is an independent risk factor for the development of both focal and global CV and also predicts poor functional outcomes and mortality after aSAH. Hp phenotyping may serve as a clinically useful tool in the critical care management of aSAH patients by allowing for early prediction of those patients who require increased vigilance due to their inherent genetic risk for the development of CV and resulting DCI and poor outcomes.

  9. Phenotype definition in epilepsy.

    PubMed

    Winawer, Melodie R

    2006-05-01

    Phenotype definition consists of the use of epidemiologic, biological, molecular, or computational methods to systematically select features of a disorder that might result from distinct genetic influences. By carefully defining the target phenotype, or dividing the sample by phenotypic characteristics, we can hope to narrow the range of genes that influence risk for the trait in the study population, thereby increasing the likelihood of finding them. In this article, fundamental issues that arise in phenotyping in epilepsy and other disorders are reviewed, and factors complicating genotype-phenotype correlation are discussed. Methods of data collection, analysis, and interpretation are addressed, focusing on epidemiologic studies. With this foundation in place, the epilepsy subtypes and clinical features that appear to have a genetic basis are described, and the epidemiologic studies that have provided evidence for the heritability of these phenotypic characteristics, supporting their use in future genetic investigations, are reviewed. Finally, several molecular approaches to phenotype definition are discussed, in which the molecular defect, rather than the clinical phenotype, is used as a starting point.

  10. Suicide for survival--death of infected erythrocytes as a host mechanism to survive malaria.

    PubMed

    Föller, Michael; Bobbala, Diwakar; Koka, Saisudha; Huber, Stephan M; Gulbins, Erich; Lang, Florian

    2009-01-01

    The pathogen of malaria, Plasmodium, enters erythrocytes and thus escapes recognition by the immune system. The pathogen induces oxidative stress to the host erythrocyte, which triggers eryptosis, the suicidal death of erythrocytes. Eryptosis is characterized by cell shrinkage, membrane blebbing and cell membrane phospholipid scrambling with phosphatidylserine exposure at the cell surface. Phosphatidylserine-exposing erythrocytes are identified by macrophages which engulf and degrade the eryptotic cells. To the extent that infected erythrocytes undergo eryptosis prior to exit of Plasmodiaand subsequent infection of other erythrocytes, the premature eryptosis may protect against malaria. Accordingly, any therapeutical intervention accelerating suicidal death of infected erythrocytes has the potential to foster elimination of infected erythrocytes, delay the development of parasitemia and favorably influence the course of malaria. Eryptosis is stimulated by a wide variety of triggers including osmotic shock, oxidative stress, energy depletion and a wide variety of xenobiotics. Diseases associated with accelerated eryptosis include sepsis, haemolytic uremic syndrome, malaria, sickle-cell anemia, beta-thalassemia, glucose-6-phosphate dehydrogenase (G6PD)-deficiency, phosphate depletion, iron deficiency and Wilson's disease. Among the known stimulators of eryptosis, paclitaxel, chlorpromazine, cyclosporine, curcumin, PGE2 and lead have indeed been shown to favourably influence the course of malaria. Moreover, sickle-cell trait, beta-thalassemia trait, glucose-6-phosphate dehydrogenase (G6PD)-deficiency and iron deficiency confer some protection against a severe course of malaria. Importantly, counteracting Plasmodia by inducing eryptosis is not expected to generate resistance of the pathogen, as the proteins involved in suicidal death of the host cell are not encoded by the pathogen and thus cannot be modified by mutations of its genes.

  11. Erythrocyte membrane phosphatidylserine exposure in obesity.

    PubMed

    Solá, Eva; Vayá, Amparo; Martínez, Marcial; Moscardó, Antonio; Corella, Dolores; Santaolaria, Maria-Luisa; España, Francisco; Hernández-Mijares, Antonio

    2009-02-01

    It has been suggested that increased erythrocyte membrane phosphatidylserine (PS) exposure could contribute to hypercoagulability and hemorheological disturbances in obesity. The aim of our study was to evaluate PS exposure in obese patients and in a control group and to correlate this with hemorheological properties, i.e., erythrocyte aggregability (EA) and deformability, and to evaluate the effect of weight loss on these parameters. An anthropometric and analytical evaluation was performed at baseline and after 3 months on a diet (very low-calorie diet for 4 weeks and low-calorie diet for 2 months) on 49 severe or morbid obese patients (37 women, 12 men) and 55 healthy volunteers (39 women, 16 men). PS exposure on erythrocyte membrane was performed by flow cytometry. Erythrocyte aggregation was measured using the Myrenne MA(1) and the Sefam aggregometer. Erythrocyte deformability was determined in a stress diffractometer. Prothrombin fragment F1+2 (F1+2) was determined as a marker of the hypercoagulable state, and plasma malondialdehyde (MDA) as an indicator of oxidative stress. Obese patients had a higher EA index, higher PS exposure on erythrocyte membranes and higher levels of MDA and F1+2. The differences in erythrocyte aggregation and F1+2 between obese patients and the control group were maintained after adjusting for PS exposure. After 3 months of diet, a significant reduction in PS exposure on erythrocyte membrane was observed. Obese patients show increased PS exposure on erythrocyte membrane, with no effect on rheological properties. Increased PS exposure could contribute to hypercoagulability in these patients. Weight loss obtained with diet treatment reduces PS exposure on erythrocyte membrane.

  12. Rh polypeptide is a major fatty acid-acylated erythrocyte membrane protein

    SciTech Connect

    de Vetten, M.P.; Agre, P.

    1988-12-05

    The erythrocyte Rh antigens contain an Mr = 32,000 integral protein which is thought to contribute in some way to the organization of surrounding phospholipid. To search for possible fatty acid acylation of the Rh polypeptide, intact human erythrocytes were incubated with (3H)palmitic acid prior to preparation of membranes and sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography. Several membrane proteins were labeled, but none corresponded to the glycophorins or membrane proteins 1-8. An Mr = 32,000 band was prominently labeled on Rh (D)-negative and -positive erythrocytes and could be precipitated from the latter with anti-D. No similar protein was labeled on membranes from Rhmod erythrocytes, a rare phenotype lacking Rh antigens. Labeling of the Rh polypeptide most likely represents palmitic acid acylation through thioester linkages. The 3H label was not extracted with chloroform/methanol, but was quantitatively eluted with hydroxylamine and co-chromatographed with palmitohydroxamate and free palmitate by thin layer chromatography. The fatty acid acylations occurred independent of protein synthesis and were completely reversed by chase with unlabeled palmitate. It is concluded that the Rh polypeptide is fatty acid-acylated, being a major substrate of an acylation-deacylation mechanism associated with the erythrocyte membrane.

  13. PRKAA1/AMPKα1 is required for autophagy-dependent mitochondrial clearance during erythrocyte maturation.

    PubMed

    Zhu, Huaiping; Foretz, Marc; Xie, Zhonglin; Zhang, Miao; Zhu, Zhiren; Xing, Junjie; Leclerc, Jocelyne; Gaudry, Murielle; Viollet, Benoit; Zou, Ming-Hui

    2014-09-01

    AMP-activated protein kinase α1 knockout (prkaa1(-/-)) mice manifest splenomegaly and anemia. The underlying molecular mechanisms, however, remain to be established. In this study, we tested the hypothesis that defective autophagy-dependent mitochondrial clearance in prkaa1(-/-) mice exacerbates oxidative stress, thereby enhancing erythrocyte destruction. The levels of ULK1 phosphorylation, autophagical flux, mitochondrial contents, and reactive oxygen species (ROS) were examined in human erythroleukemia cell line, K562 cells, as well as prkaa1(-/-) mouse embryonic fibroblasts and erythrocytes. Deletion of Prkaa1 resulted in the inhibition of ULK1 phosphorylation at Ser555, prevented the formation of ULK1 and BECN1- PtdIns3K complexes, and reduced autophagy capacity. The suppression of autophagy was associated with enhanced damaged mitochondrial accumulation and ROS production. Compared with wild-type (WT) mice, prkaa1(-/-) mice exhibited a shortened erythrocyte life span, hemolytic destruction of erythrocytes, splenomegaly, and anemia, all of which were alleviated by the administration of either rapamycin to activate autophagy or Mito-tempol, a mitochondria-targeted antioxidant, to scavenge mitochondrial ROS. Furthermore, transplantation of WT bone marrow into prkaa1(-/-) mice restored mitochondrial removal, reduced intracellular ROS levels, and normalized hematologic parameters and spleen size. Conversely, transplantation of prkaa1 (-/-) bone marrow into WT mice recapitulated the prkaa1(-/-) mouse phenotypes. We conclude that PRKAA1-dependent autophagy-mediated clearance of damaged mitochondria is required for erythrocyte maturation and homeostasis.

  14. Parental effects modulate seed longevity: exploring parental and offspring phenotypes to elucidate pre-zygotic environmental influences.

    PubMed

    Kochanek, Jitka; Steadman, Kathryn J; Probert, Robin J; Adkins, Steve W

    2011-07-01

    • Seed longevity, which is essential for germplasm conservation and survival of many land plant species, can vary considerably within species and cultivars. Here, we explore the relationship between parental and offspring phenotypes to elucidate how pre-zygotic environment affects seed longevity. • Plants of the wild species Plantago cunninghamii were exposed to wet or dry soil within a warm or cool glasshouse until flowering and then moved to a common environment. Seeds subsequently produced were collected at maturity, and longevity was assessed by controlled ageing at 45°C, 60% relative humidity. Multivariate analysis was used to examine relationships between the parental and offspring phenotypes. • The pre-zygotic environment resulted in a highly plastic parental response which was passed on to offspring seeds and changed their longevity (p(50)) by more than a factor of 2. Seed longevity is a function of the seed population's distribution of deaths in time (σ) and quality (K(i)); σ was associated with plant size, and K(i) with reproductive plant traits. • The pre-zygotic growth environment modulated seed longevity via a parental effect. Reproductive performance and seed quality (K(i)) were highly correlated with each other and unrelated to the maternal plant phenotype. Hence seed quality may be associated with the paternal plant response to the environment. PMID:21434931

  15. Inherited and environmental influences on a childhood co-occurring symptom phenotype: Evidence from an adoption study.

    PubMed

    Roos, Leslie E; Fisher, Philip A; Shaw, Daniel S; Kim, Hyoun K; Neiderhiser, Jenae M; Reiss, David; Natsuaki, Misake N; Leve, Leslie D

    2016-02-01

    Risk factors for the childhood development of co-occurring internalizing and externalizing symptoms are not well understood, despite a high prevalence and poor clinical outcomes associated with this co-occurring phenotype. We examined inherited and environmental risk factors for co-occurring symptoms in a sample of children adopted at birth and their birth mothers and adoptive mothers (N = 293). Inherited risk factors (i.e., birth mothers' processing speed and internalizing symptoms) and environmental risk factors (i.e., adoptive mothers' processing speed, internalizing symptoms, and uninvolved parenting) were examined as predictors for the development of internalizing-only, externalizing-only, or co-occurring symptoms using structural equation modeling. Results suggested a unique pattern of predictive factors for the co-occurring phenotype, with risk conferred by adoptive mothers' uninvolved parenting, birth mothers' slower processing speed, and the birth mothers' slower processing speed in tandem with adoptive mothers' higher internalizing symptoms. Additional analyses indicated that when co-occurring-symptom children were incorporated into internalizing and externalizing symptom groups, differential risk factors for externalizing and internalizing symptoms emerged. The findings suggest that spurious results may be found when children with co-occurring symptoms are not examined as a unique phenotypic group.

  16. Specific Preferences in Lineage Choice and Phenotypic Plasticity of Glioma Stem Cells Under BMP4 and Noggin Influence.

    PubMed

    Videla Richardson, Guillermo Agustín; Garcia, Carolina Paola; Roisman, Alejandro; Slavutsky, Irma; Fernandez Espinosa, Damián Darío; Romorini, Leonardo; Miriuka, Santiago Gabriel; Arakaki, Naomi; Martinetto, Horacio; Scassa, María Elida; Sevlever, Gustavo Emilio

    2016-01-01

    Although BMP4-induced differentiation of glioma stem cells (GSCs) is well recognized, details of the cellular responses triggered by this morphogen are still poorly defined. In this study, we established several GSC-enriched cell lines (GSC-ECLs) from high-grade gliomas. The expansion of these cells as adherent monolayers, and not as floating neurospheres, enabled a thorough study of the phenotypic changes that occurred during their differentiation. Herein, we evaluated GSC-ECLs' behavior toward differentiating conditions by depriving them of growth factors and/or by adding BMP4 at different concentrations. After analyzing cellular morphology, proliferation and lineage marker expression, we determined that GSC-ECLs have distinct preferences in lineage choice, where some of them showed an astrocyte fate commitment and others a neuronal one. We found that this election seems to be dictated by the expression pattern of BMP signaling components present in each GSC-ECL. Additionally, treatment of GSC-ECLs with the BMP antagonist, Noggin, also led to evident phenotypic changes. Interestingly, under certain conditions, some GSC-ECLs adopted an unexpected smooth muscle-like phenotype. As a whole, our findings illustrate the wide differentiation potential of GSCs, highlighting their molecular complexity and paving a way to facilitate personalized differentiating therapies.

  17. Inherited and Environmental Influences on a Childhood Co-Occurring Symptom Phenotype: Evidence From an Adoption Study

    PubMed Central

    Roos, Leslie E.; Fisher, Philip A.; Shaw, Daniel S.; Kim, Hyoun K.; Neiderhiser, Jenae M.; Reiss, David; Natsuaki, Misaki N.; Leve, Leslie D.

    2015-01-01

    Risk factors for the childhood development of co-occurring internalizing and externalizing symptoms are not well understood, despite a high prevalence and poor clinical outcomes associated with this co-occurring phenotype. We examined inherited and environmental risk factors for co-occurring symptoms in a sample of children adopted at birth and their birth mothers and adoptive mothers (N = 293). Inherited risk factors (i.e., birth mothers’ processing speed and internalizing symptoms) and environmental risk factors (i.e., adoptive mothers’ processing speed, internalizing symptoms, and uninvolved parenting) were examined as predictors for the development of internalizing-only, externalizing-only, or co-occurring symptoms using structural equation modeling. Results suggested a unique pattern of predictive factors for the co-occurring phenotype, with risk conferred by adoptive mothers’ uninvolved parenting, birth mothers’ slower processing speed, and the birth mothers’ slower processing speed in tandem with adoptive mothers’ higher internalizing symptoms. Additional analyses indicated that when co-occurring-symptom children were incorporated into internalizing and externalizing symptom groups, differential risk factors for externalizing and internalizing symptoms emerged. The findings suggest that spurious results may be found when children with co-occurring symptoms are not examined as a unique phenotypic group. PMID:25851306

  18. Triggering of Programmed Erythrocyte Death by Alantolactone

    PubMed Central

    Alzoubi, Kousi; Calabrò, Salvatrice; Egler, Jasmin; Faggio, Caterina; Lang, Florian

    2014-01-01

    The sesquiterpene alantolactone counteracts malignancy, an effect at least in part due to stimulation of suicidal death or apoptosis of tumor cells. Signaling of alantolactone induced apoptosis involves altered gene expression and mitochondrial depolarization. Erythrocytes lack mitochondria and nuclei but may enter suicidal death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine exposure at the erythrocyte surface. Cellular mechanisms involved in triggering of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i) and oxidative stress. The present study explored, whether alantolactone stimulates eryptosis. To this end, erythrocyte volume was estimated from forward scatter, phosphatidylserine-exposure at the erythrocyte surface from FITC-annexin-V-binding, [Ca2+]i from Fluo3-fluorescence, ceramide abundance from binding of fluorescent antibodies, and oxidative stress from 2',7'-dichlorodihydrofluorescein-diacetate (DCFDA) fluorescence. As a result, a 48 h exposure of human erythrocytes to alantolactone (≥20 μM) significantly decreased erythrocyte forward scatter and increased the percentage of annexin-V-binding cells. Alantolactone significantly increased Fluo3 fluorescence (60 μM), ceramide abundance (60 μM) and DCFDA fluorescence (≥40 μM). The effect of alantolactone (60 μM) on annexin-V-binding was not significantly modified by removal of extracellular Ca2+. In conclusion, alantolactone stimulates suicidal erythrocyte death or eryptosis, an effect paralleled by increase of [Ca2+]i, ceramide abundance and oxidative stress. PMID:25533522

  19. Erythrocyte reference values in Emirati people with and without α+ thalassemia

    PubMed Central

    2011-01-01

    Background Interpreting the erythroid lineage in populations with high frequency of α+ thalassemia allele is challenging due to the high prevalence of α+ thalassemia homozygotes. For such populations, separate reference values for normal and α+ thalassemia homozygotes are needed. Methods We studied the erythroid lineage in 1,079 citizens of United Arab Emirates (UAE). Subjects with abnormal hemoglobin (39), iron deficiency (136) or erroneous entries (8) were excluded. MCV distribution in the remaining individuals (896) was visibly bimodal. Statistical mixture analysis with Normix program was used to separate subpopulations with normal and small red cells. Hardy-Weinberg equation was used to estimate genotype frequencies. Results MCV of 78.0 fl separated phenotype-derived normal homozygotes (715) from phenotype-derived α+ thalassemia homozygotes (181). The erythrocyte indices were significantly different between the two groups (p < 0.0001). The overall prevalence of phenotype-derived α+ thalassemia homozygotes (-α/-α) was 0.20 and markedly varied among tribes, 0 to 0.31 (Mean = 0.15). The frequency of phenotype-derived α+ thalassemia allele was 0.44; when accounting for tribal population structure and inbreeding, the calculated frequency was 0.34. These values were very similar to those found in the same population by genotyping and other phenotyping methods. The erythrocyte reference values for phenotype-derived normal homozygotes in Emiratis closely overlapped with those for Caucasians and normal homozygotes defined by genotyping. The reference values for phenotype-derived α+ thalassemia homozygotes in Emiratis also closely overlapped with those for α+ thalassemia homozygotes defined by genotyping. Conclusion In populations with frequent α+ thalassemia mutations, two sets of erythrocyte reference values could be determined without genotyping. PMID:21345240

  20. Human erythrocyte Band 3 functions as a receptor for the sialic acid-independent invasion of Plasmodium falciparum. Role of the RhopH3-MSP1 complex

    PubMed Central

    Baldwin, Michael; Yamodo, Innocent; Ranjan, Ravi; Li, Xuerong; Mines, Gregory; Marinkovic, Marina; Hanada, Toshihiko; Oh, Steven S.; Chishti, Athar H.

    2014-01-01

    Plasmodium falciparum takes advantage of two broadly defined alternate invasion pathways when infecting human erythrocytes: one that depends on and the other that is independent of host sialic acid residues on the erythrocyte surface. Within the sialic acid-dependent (SAD) and sialic acid-independent (SAID) invasion pathways, several alternate host receptors are used by Plasmodium falciparum based on its particular invasion phenotype. Earlier, we reported that two putative extracellular regions of human erythrocyte band 3 termed 5C and 6A function as host invasion receptor segments binding parasite proteins MSP1 and MSP9 via a SAID mechanism. In this study, we developed two mono-specific anti-peptide chicken IgY antibodies to demonstrate that the 5C and 6A regions of band 3 are exposed on the surface of human erythrocytes. These antibodies inhibited erythrocyte invasion by the Plasmodium falciparum 3D7 and 7G8 strains (SAID invasion phenotype), and the blocking effect was enhanced in sialic acid-depleted erythrocytes. In contrast, the IgY antibodies had only a marginal inhibitory effect on FCR3 and Dd2 strains (SAD invasion phenotype). A direct biochemical interaction between erythrocyte band 3 epitopes and parasite RhopH3, identified by the yeast two-hybrid screen, was established. RhopH3 formed a complex with MSP119 and 5ABC region of band 3, and a recombinant segment of RhopH3 inhibited parasite invasion in human erythrocytes. Together, these findings provide evidence that erythrocyte band 3 functions as a major host invasion receptor in the SAID invasion pathway by assembling a multi-protein complex composed of parasite ligands RhopH3 and MSP1. PMID:25157665

  1. An in vitro study of adrenaline effect on human erythrocyte properties in both gender.

    PubMed

    Hilário, Sandra; Saldanha, Carlota; Martins e Silva, J

    2003-01-01

    The possibility that erythrocytes may function as a reservoir for noradrenaline and adrenaline and as a modulator of circulating catecholamine concentrations had been suggested. The aim of this work was to study the adrenaline effect on erythrocyte membrane fluidity, acetylcholinesterase (AChE) enzyme activity, P(50) and erythrocyte deformability and also to verify if the role of adrenaline on erythrocyte properties is sex-dependent. Blood samples from 42 healthy donors were obtained, and its aliquots incubated 30 min without (control) and with 10(-5) M concentrations of adrenaline alone (A(1)) and adrenaline with an alpha and an beta-blocker (A(2)). Results demonstrate that initial AChE values in female are higher (perythrocyte membrane fluidity are very similar but behaviour became differently (perythrocyte deformability are verified at high shear stress values (perythrocyte acetylcholinesterase enzyme activity, membrane fluidity and erythrocyte deformability under adrenaline influence were found.

  2. Influence of autologous dendritic cells on cytokine-induced killer cell proliferation, cell phenotype and antitumor activity in vitro

    PubMed Central

    Cao, Jingsong; Chen, Cong; Wang, Yuhuan; Chen, Xuecheng; Chen, Zeying; Luo, Xiaoling

    2016-01-01

    Dendritic cell (DCs) are essential antigen processing and presentation cells that play a key role in the immune response. In this study, DCs were co-cultured with cytokine-induced killer cells (DC-CIKs) in vitro to detect changes in cell proliferation, cell phenotype and cell cytotoxicity. The results revealed that the DCs were suitable for co-culture with CIKs at day 7, and that cell quantity of DC-CIKs was lower than that of CIKs until day 11, but it was significantly improved to 1.17-fold that of CIKs at day 13. Flow cytometry was used to detect the cell phenotype of CIKs and DC-CIKs. Compared with CIKs at day 13, the percentage of CD3+, CD3+CD4+, CD3+CD8+ and CD3+CD56+ T cells in DC-CIKs was significantly improved 1.02, 1.79, 1.26 and 2.44-fold, respectively. In addition, trypan blue staining analysis demonstrated that the cell viability of CIKs and DC-CIKs was 96% and 98%, respectively. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis verified that CIK and DC-CIK cytotoxicity in Hela cells was 58% and 80%, respectively, with a significant difference. Taken together, our results indicate that the cell proliferation, cell phenotype and antitumor activity of CIKs were all enhanced following co-culture with DCs in vitro. These results are likely to be useful for DC-CIK application in antitumor therapies. PMID:27602134

  3. Influence of autologous dendritic cells on cytokine-induced killer cell proliferation, cell phenotype and antitumor activity in vitro

    PubMed Central

    Cao, Jingsong; Chen, Cong; Wang, Yuhuan; Chen, Xuecheng; Chen, Zeying; Luo, Xiaoling

    2016-01-01

    Dendritic cell (DCs) are essential antigen processing and presentation cells that play a key role in the immune response. In this study, DCs were co-cultured with cytokine-induced killer cells (DC-CIKs) in vitro to detect changes in cell proliferation, cell phenotype and cell cytotoxicity. The results revealed that the DCs were suitable for co-culture with CIKs at day 7, and that cell quantity of DC-CIKs was lower than that of CIKs until day 11, but it was significantly improved to 1.17-fold that of CIKs at day 13. Flow cytometry was used to detect the cell phenotype of CIKs and DC-CIKs. Compared with CIKs at day 13, the percentage of CD3+, CD3+CD4+, CD3+CD8+ and CD3+CD56+ T cells in DC-CIKs was significantly improved 1.02, 1.79, 1.26 and 2.44-fold, respectively. In addition, trypan blue staining analysis demonstrated that the cell viability of CIKs and DC-CIKs was 96% and 98%, respectively. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis verified that CIK and DC-CIK cytotoxicity in Hela cells was 58% and 80%, respectively, with a significant difference. Taken together, our results indicate that the cell proliferation, cell phenotype and antitumor activity of CIKs were all enhanced following co-culture with DCs in vitro. These results are likely to be useful for DC-CIK application in antitumor therapies.

  4. Isolation site influences virulence phenotype of serotype 14 Streptococcus pneumoniae strains belonging to multilocus sequence type 15.

    PubMed

    Amin, Zarina; Harvey, Richard M; Wang, Hui; Hughes, Catherine E; Paton, Adrienne W; Paton, James C; Trappetti, Claudia

    2015-12-01

    Streptococcus pneumoniae is a diverse species causing invasive as well as localized infections that result in massive global morbidity and mortality. Strains vary markedly in pathogenic potential, but the molecular basis is obscured by the diversity and plasticity of the pneumococcal genome. We have previously reported that S. pneumoniae serotype 3 isolates belonging to the same multilocus sequence type (MLST) differed markedly in in vitro and in vivo phenotypes, in accordance with the clinical site of isolation, suggesting stable niche adaptation within a clonal lineage. In the present study, we have extended our analysis to serotype 14 clinical isolates from cases of sepsis or otitis media that belong to the same MLST (ST15). In a murine intranasal challenge model, five ST15 isolates (three from blood and two from ears) colonized the nasopharynx to similar extents. However, blood and ear isolates exhibited significant differences in bacterial loads in other host niches (lungs, ear, and brain) at both 24 and 72 h postchallenge. In spite of these differences, blood and ear isolates were present in the lungs at similar levels at 6 h postchallenge, suggesting that early immune responses may underpin the distinct virulence phenotypes. Transcriptional analysis of lung tissue from mice infected for 6 h with blood isolates versus ear isolates revealed 8 differentially expressed genes. Two of these were exclusively expressed in response to infection with the ear isolate. These results suggest a link between the differential capacities to elicit early innate immune responses and the distinct virulence phenotypes of clonally related S. pneumoniae strains.

  5. Common colorectal cancer risk alleles contribute to the multiple colorectal adenoma phenotype, but do not influence colonic polyposis in FAP

    PubMed Central

    Cheng, Timothy H T; Gorman, Maggie; Martin, Lynn; Barclay, Ella; Casey, Graham; Newcomb, Polly A; Casey, Graham; Conti, David V; Schumacher, Fred; Gallinger, Steve; Lindor, Noralane M; Hopper, John; Jenkins, Mark; Hunter, David J; Kraft, Peter; Jacobs, Kevin B; Cox, David G; Yeager, Meredith; Hankinson, Susan E; Wacholder, Sholom; Wang, Zhaoming; Welch, Robert; Hutchinson, Amy; Wang, Junwen; Yu, Kai; Chatterjee, Nilanjan; Orr, Nick; Willett, Walter C; Colditz, Graham A; Ziegler, Regina G; Berg, Christine D; Buys, Saundra S; McCarty, Catherine A; Feigelson, Heather Spencer; Calle, Eugenia E; Thun, Michael J; Hayes, Richard B; Tucker, Margaret; Gerhard, Daniela S; Fraumeni, Joseph F; Hoover, Robert N; Thomas, Gilles; Chanock, Stephen J; Yeager, Meredith; Chatterjee, Nilanjan; Ciampa, Julia; Jacobs, Kevin B; Gonzalez-Bosquet, Jesus; Hayes, Richard B; Kraft, Peter; Wacholder, Sholom; Orr, Nick; Berndt, Sonja; Yu, Kai; Hutchinson, Amy; Wang, Zhaoming; Amundadottir, Laufey; Feigelson, Heather Spencer; Thun, Michael J; Diver, W Ryan; Albanes, Demetrius; Virtamo, Jarmo; Weinstein, Stephanie; Schumacher, Fredrick R; Cancel-Tassin, Geraldine; Cussenot, Olivier; Valeri, Antoine; Andriole, Gerald L; Crawford, E David; Haiman, Christopher A; Henderson, Brian; Kolonel, Laurence; Marchand, Loic Le; Siddiq, Afshan; Riboli, Elio; Key, Timothy J; Kaaks, Rudolf; Isaacs, William; Isaacs, Sarah; Wiley, Kathleen E; Gronberg, Henrik; Wiklund, Fredrik; Stattin, Pär; Xu, Jianfeng; Zheng, S Lilly; Sun, Jielin; Vatten, Lars J; Hveem, Kristian; Kumle, Merethe; Tucker, Margaret; Gerhard, Daniela S; Hoover, Robert N; Fraumeni, Joseph F; Hunter, David J; Thomas, Gilles; Chanock, Stephen J; Purdue, Mark P; Johansson, Mattias; Zelenika, Diana; Toro, Jorge R; Scelo, Ghislaine; Moore, Lee E; Prokhortchouk, Egor; Wu, Xifeng; Kiemeney, Lambertus A; Gaborieau, Valerie; Jacobs, Kevin B; Chow, Wong-Ho; Zaridze, David; Matveev, Vsevolod; Lubinski, Jan; Trubicka, Joanna; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Péter; Fabianova, Eleonora; Bucur, Alexandru; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Boffetta, Paolo; Colt, Joanne S; Davis, Faith G; Schwartz, Kendra L; Banks, Rosamonde E; Selby, Peter J; Harnden, Patricia; Berg, Christine D; Hsing, Ann W; Grubb III, Robert L; Boeing, Heiner; Vineis, Paolo; Clavel-Chapelon, Françoise; Palli, Domenico; Tumino, Rosario; Krogh, Vittorio; Panico, Salvatore; Duell, Eric J; Quirós, José Ramón; Sanchez, Maria-José; Navarro, Carmen; Ardanaz, Eva; Dorronsoro, Miren; Khaw, Kay-Tee; Allen, Naomi E; Bueno-de-Mesquita, H Bas; Peeters, Petra H M; Trichopoulos, Dimitrios; Linseisen, Jakob; Ljungberg, Börje; Overvad, Kim; Tjønneland, Anne; Romieu, Isabelle; Riboli, Elio; Mukeria, Anush; Shangina, Oxana; Stevens, Victoria L; Thun, Michael J; Diver, W Ryan; Gapstur, Susan M; Pharoah, Paul D; Easton, Douglas F; Albanes, Demetrius; Weinstein, Stephanie J; Virtamo, Jarmo; Vatten, Lars; Hveem, Kristian; Njølstad, Inger; Tell, Grethe S; Stoltenberg, Camilla; Kumar, Rajiv; Koppova, Kvetoslava; Cussenot, Olivier; Benhamou, Simone; Oosterwijk, Egbert; Vermeulen, Sita H; Aben, Katja K H; van der Marel, Saskia L; Ye, Yuanqing; Wood, Christopher G; Pu, Xia; Mazur, Alexander M; Boulygina, Eugenia S; Chekanov, Nikolai N; Foglio, Mario; Lechner, Doris; Gut, Ivo; Heath, Simon; Blanche, Hélène; Hutchinson, Amy; Thomas, Gilles; Wang, Zhaoming; Yeager, Meredith; Fraumeni, Joseph F; Skryabin, Konstantin G; McKay, James D; Rothman, Nathaniel; Chanock, Stephen J; Lathrop, Mark; Brennan, Paul; Saunders, Brian; Thomas, Huw; Clark, Sue; Tomlinson, Ian

    2015-01-01

    The presence of multiple (5–100) colorectal adenomas suggests an inherited predisposition, but the genetic aetiology of this phenotype is undetermined if patients test negative for Mendelian polyposis syndromes such as familial adenomatous polyposis (FAP) and MUTYH-associated polyposis (MAP). We investigated whether 18 common colorectal cancer (CRC) predisposition single-nucleotide polymorphisms (SNPs) could help to explain some cases with multiple adenomas who phenocopied FAP or MAP, but had no pathogenic APC or MUTYH variant. No multiple adenoma case had an outlying number of CRC SNP risk alleles, but multiple adenoma patients did have a significantly higher number of risk alleles than population controls (P=5.7 × 10−7). The association was stronger in those with ≥10 adenomas. The CRC SNPs accounted for 4.3% of the variation in multiple adenoma risk, with three SNPs (rs6983267, rs10795668, rs3802842) explaining 3.0% of the variation. In FAP patients, the CRC risk score did not differ significantly from the controls, as we expected given the overwhelming effect of pathogenic germline APC variants on the phenotype of these cases. More unexpectedly, we found no evidence that the CRC SNPs act as modifier genes for the number of colorectal adenomas in FAP patients. In conclusion, common colorectal tumour risk alleles contribute to the development of multiple adenomas in patients without pathogenic germline APC or MUTYH variants. This phenotype may have ‘polygenic' or monogenic origins. The risk of CRC in relatives of multiple adenoma cases is probably much lower for cases with polygenic disease, and this should be taken into account when counselling such patients. PMID:24801760

  6. Purification and Biochemical Characterization of Glutathione S-Transferase from Down Syndrome and Normal Children Erythrocytes: A Comparative Study

    ERIC Educational Resources Information Center

    Hamed, Ragaa R.; Maharem, Tahany M.; Abdel-Meguid, Nagwa; Sabry, Gilane M.; Abdalla, Abdel-Monem; Guneidy, Rasha A.

    2011-01-01

    Down syndrome (DS) is the phenotypic manifestation of trisomy 21. Our study was concerned with the characterization and purification of glutathione S-transferase enzyme (GST) from normal and Down syndrome (DS) erythrocytes to illustrate the difference in the role of this enzyme in the cell. Glutathione S-transferase and glutathione (GSH) was…

  7. The Molecular Basis of Erythrocyte Shape

    NASA Astrophysics Data System (ADS)

    Elgsaeter, Arnljot; Stokke, Bjorn T.; Mikkelsen, Arne; Branton, Daniel

    1986-12-01

    Recent discoveries about the molecular organization and physical properties of the mammalian erythrocyte membrane and its associated structural proteins can now be used to explain, and may eventually be used to predict, the shape of the erythrocyte. Such explanations are possible because the relatively few structural proteins of the erythrocyte are regularly distributed over the entire cytoplasmic surface of the cell membrane and because the well-understood topological associations of these proteins seem to be stable in comparison with the time required for the cell to change shape. These simplifications make the erythrocyte the first nonmuscle cell for which it will be possible to extend our knowledge of molecular interactions to the next hierarchical level of organization that deals with shape and shape transformations.

  8. The Erythrocyte Ghost Is a Perfect Osmometer

    PubMed Central

    Kwant, W. O.; Seeman, Philip

    1970-01-01

    The osmotic swelling of intact erythrocytes in hypotonic solutions was measured using microhematocrit tubes, Van Allen tubes, and a calibrated Coulter counter. In agreement with earlier workers the intact cells did not behave as perfect osmometers, the cells swelling less than predicted by the Boyle-van't Hoff law. Erythrocyte ghosts were prepared from fresh intact erythrocytes by one-step hemolysis in 0.25% NaCl at an extremely dilute concentration of cells and the membranes were sealed at 37°. The ghosts were mixed with NaCl solutions of different osmolarities and the MCV (mean cell volume) of the shrunken cells immediately monitored by a calibrated Coulter counter. It was found that the MCV values of the shrunken ghosts were accurately predicted by the Boyle-van't Hoff law. These results indicate that these erythrocyte ghosts behaved as perfect osmometers. PMID:5413078

  9. Triggering of Erythrocyte Death by Triparanol

    PubMed Central

    Officioso, Arbace; Manna, Caterina; Alzoubi, Kousi; Lang, Florian

    2015-01-01

    The cholesterol synthesis inhibitor Triparanol has been shown to trigger apoptosis in several malignancies. Similar to the apoptosis of nucleated cells, erythrocytes may enter eryptosis, the suicidal death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include oxidative stress which may activate erythrocytic Ca2+ permeable unselective cation channels with subsequent Ca2+ entry and increase of cytosolic Ca2+ activity ([Ca2+]i). The present study explored whether and how Triparanol induces eryptosis. To this end, phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and ROS formation from 2’,7’-dichlorodihydrofluorescein diacetate (DCFDA) dependent fluorescence. As a result, a 48 h exposure of human erythrocytes to Triparanol (20 µM) significantly increased DCFDA fluorescence and significantly increased Fluo3-fluorescence. Triparanol (15 µM) significantly increased the percentage of annexin-V-binding cells, and significantly decreased the forward scatter. The effect of Triparanol on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. In conclusion, Triparanol leads to eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane. Triparanol is at least in part effective by stimulating ROS formation and Ca2+ entry. PMID:26305256

  10. Fya/Fyb antigen polymorphism in human erythrocyte Duffy antigen affects susceptibility to Plasmodium vivax malaria

    PubMed Central

    King, Christopher L.; Adams, John H.; Xianli, Jia; Grimberg, Brian T.; McHenry, Amy M.; Greenberg, Lior J.; Siddiqui, Asim; Howes, Rosalind E.; da Silva-Nunes, Monica; Ferreira, Marcelo U.; Zimmerman, Peter A.

    2011-01-01

    Plasmodium vivax (Pv) is a major cause of human malaria and is increasing in public health importance compared with falciparum malaria. Pv is unique among human malarias in that invasion of erythrocytes is almost solely dependent on the red cell's surface receptor, known as the Duffy blood-group antigen (Fy). Fy is an important minor blood-group antigen that has two immunologically distinct alleles, referred to as Fya or Fyb, resulting from a single-point mutation. This mutation occurs within the binding domain of the parasite's red cell invasion ligand. Whether this polymorphism affects susceptibility to clinical vivax malaria is unknown. Here we show that Fya, compared with Fyb, significantly diminishes binding of Pv Duffy binding protein (PvDBP) at the erythrocyte surface, and is associated with a reduced risk of clinical Pv in humans. Erythrocytes expressing Fya had 41–50% lower binding compared with Fyb cells and showed an increased ability of naturally occurring or artificially induced antibodies to block binding of PvDBP to their surface. Individuals with the Fya+b− phenotype demonstrated a 30–80% reduced risk of clinical vivax, but not falciparum malaria in a prospective cohort study in the Brazilian Amazon. The Fya+b− phenotype, predominant in Southeast Asian and many American populations, would confer a selective advantage against vivax malaria. Our results also suggest that efficacy of a PvDBP-based vaccine may differ among populations with different Fy phenotypes. PMID:22123959

  11. Matrix molecule influence on chondrocyte phenotype and proteoglycan 4 expression by alginate-embedded zonal chondrocytes and mesenchymal stem cells.

    PubMed

    Coates, Emily E; Riggin, Corinne N; Fisher, John P

    2012-12-01

    Articular cartilage resists load and provides frictionless movement at joint surfaces. The tissue is organized into the superficial, middle, deep, and calcified zones throughout its depth, each which serve distinct functions. Proteoglycan 4 (PRG4), found in the superficial zone, is a critical component of the joint's lubricating mechanisms. Maintenance of both the chondrocyte and zonal chondrocyte phenotype remain challenges for in vitro culture and tissue engineering. Here we investigate the expression of PRG4 mRNA and protein by primary bovine superficial zone chondrocytes, middle/deep zone chondrocytes, and mesenchymal stem cells encapsulated in alginate hydrogels with hyaluronic acid (HA) and chondroitin sulfate (CS) additives. Chondrogenic phenotype and differentiation markers are evaluated by mRNA expression, histochemical, and immunohistochemical staining. Results show middle/deep cells express no measurable PRG4 mRNA by day 7. In contrast, superficial zone cells express elevated PRG4 mRNA throughout culture time. This expression can be significantly enhanced up to 15-fold by addition of both HA and CS to scaffolds. Conversely, PRG4 mRNA expression is downregulated (up to 5-fold) by CS and HA in differentiating MSCs, possibly due to build up of entrapped protein. HA and CS demonstrate favorable effects on chondrogenesis by upregulating transcription factor Sox9 mRNA (up to 4.6-fold) and downregulating type I collagen mRNA (up to 18-fold). Results highlight the important relationship between matrix components and expression of critical lubricating proteins in an engineered cartilage scaffold. PMID:22674584

  12. Influence of hydrogel mechanical properties and mesh size on vocal fold fibroblast extracellular matrix production and phenotype

    PubMed Central

    Hahn, Mariah S.; Liao, Huimin; Munoz-Pinto, Dany; Qu, Xin; Hou, Yaping; Grunlan, Melissa A.

    2008-01-01

    Current clinical management of vocal fold (VF) scarring produces inconsistent and often suboptimal results. Researchers are investigating a number of alternative treatments for VF lamina propria (LP) scarring, including designer implant materials for functional LP regeneration. In the present study, we investigate the effects of the initial scaffold elastic modulus and mesh size on encapsulated VF fibroblast (VFF) extracellular matrix (ECM) production toward rational scaffold design. Polyethylene glycol diacrylate (PEGDA) hydrogels were selected for this study since their material properties, including mechanical properties, mesh size, degradation rate and bioactivity, can be tightly controlled and systematically modified. Porcine VFF were encapsulated in four PEGDA hydrogels with degradation half lives of ~25 days and initial elastic compressive moduli ranging from ~30 to 100 kPa and initial mesh sizes ranging from ~9 to 27 nm. After 30 days of static culture, VFF ECM production and phenotype in each formulation was assessed biochemically and histologically. Sulfated glycosaminoglycan synthesis increased in similar degree with both increasing initial modulus and decreasing initial mesh size. In contrast, elastin production decreased with increasing initial modulus but increased with decreasing initial mesh size. Both collagen deposition and the induction of a myofibroblastic phenotype depended strongly on initial mesh size but appeared largely unaffected by variations in initial modulus. The present results indicate that scaffold mesh size warrants further investigation as a critical regulator of VFF ECM synthesis. Furthermore, this study validates a systematic and controlled approach for analyzing VFF response to scaffold properties, which should aid in rational scaffold selection/design. PMID:18515199

  13. Short-Term Effects of Chlorpromazine on Oxidative Stress in Erythrocyte Functionality: Activation of Metabolism and Membrane Perturbation.

    PubMed

    Ficarra, Silvana; Russo, Annamaria; Barreca, Davide; Giunta, Elena; Galtieri, Antonio; Tellone, Ester

    2016-01-01

    The purpose of this paper is to focus on the short-term effects of chlorpromazine on erythrocytes because it is reported that the drug, unstable in plasma but more stable in erythrocytes, interacts with erythrocyte membranes, membrane lipids, and hemoglobin. There is a rich literature about the side and therapeutic effects or complications due to chlorpromazine, but most of these studies explore the influence of long-term treatment. We think that evaluating the short-term effects of the drug may help to clarify the sequence of chlorpromazine molecular targets from which some long-term effects derive. Our results indicate that although the drug is primarily intercalated in the innermost side of the membrane, it does not influence band 3 anionic flux, lipid peroxidation, and protein carbonylation processes. On the other hand, it destabilizes and increases the autooxidation of haemoglobin, induces activation of caspase 3, and, markedly, influences the ATP and reduced glutathione levels, with subsequent exposure of phosphatidylserine at the erythrocyte surface. Overall our observations on the early stage of chlorpromazine influence on erythrocytes may contribute to better understanding of new and interesting characteristics of this compound improving knowledge of erythrocyte metabolism. PMID:27579150

  14. Short-Term Effects of Chlorpromazine on Oxidative Stress in Erythrocyte Functionality: Activation of Metabolism and Membrane Perturbation

    PubMed Central

    Ficarra, Silvana; Russo, Annamaria; Barreca, Davide; Giunta, Elena; Galtieri, Antonio

    2016-01-01

    The purpose of this paper is to focus on the short-term effects of chlorpromazine on erythrocytes because it is reported that the drug, unstable in plasma but more stable in erythrocytes, interacts with erythrocyte membranes, membrane lipids, and hemoglobin. There is a rich literature about the side and therapeutic effects or complications due to chlorpromazine, but most of these studies explore the influence of long-term treatment. We think that evaluating the short-term effects of the drug may help to clarify the sequence of chlorpromazine molecular targets from which some long-term effects derive. Our results indicate that although the drug is primarily intercalated in the innermost side of the membrane, it does not influence band 3 anionic flux, lipid peroxidation, and protein carbonylation processes. On the other hand, it destabilizes and increases the autooxidation of haemoglobin, induces activation of caspase 3, and, markedly, influences the ATP and reduced glutathione levels, with subsequent exposure of phosphatidylserine at the erythrocyte surface. Overall our observations on the early stage of chlorpromazine influence on erythrocytes may contribute to better understanding of new and interesting characteristics of this compound improving knowledge of erythrocyte metabolism. PMID:27579150

  15. Frailty phenotypes in the elderly based on cluster analysis: a longitudinal study of two Danish cohorts. Evidence for a genetic influence on frailty.

    PubMed

    Dato, Serena; Montesanto, Alberto; Lagani, Vincenzo; Jeune, Bernard; Christensen, Kaare; Passarino, Giuseppe

    2012-06-01

    Frailty is a physiological state characterized by the deregulation of multiple physiologic systems of an aging organism determining the loss of homeostatic capacity, which exposes the elderly to disability, diseases, and finally death. An operative definition of frailty, useful for the classification of the individual quality of aging, is needed. On the other hand, the documented heterogeneity in the quality of aging among different geographic areas suggests the necessity for a frailty classification approach providing population-specific results. Moreover, the contribution of the individual genetic background on the frailty status is still questioned. We investigated the applicability of a cluster analysis approach based on specific geriatric parameters, previously set up and validated in a southern Italian population, to two large longitudinal Danish samples. In both cohorts, we identified groups of subjects homogeneous for their frailty status and characterized by different survival patterns. A subsequent survival analysis availing of Accelerated Failure Time models allowed us to formulate an operative index able to correlate classification variables with survival probability. From these models, we quantified the differential effect of various parameters on survival, and we estimated the heritability of the frailty phenotype by exploiting the twin pairs in our sample. These data suggest the presence of a genetic influence on the frailty variability and indicate that cluster analysis can define specific frailty phenotypes in each population. PMID:21567248

  16. Polymorphism in the M sub r 32,000 Rh protein purified from Rh(D)-positive and -negative erythrocytes

    SciTech Connect

    Saboori, A.M.; Smith, B.L.; Agre, P. )

    1988-06-01

    A M{sub r} 32,000 integral membrane protein has previously been identified on erythrocytes bearing the Rh(D) antigen and is thought to contain the antigenic variations responsible for the different Rh phenotypes. To study it on a biochemical level, a simple large-scale method was developed to purify the M{sub r} 32,000 Rh protein from multiple units of Rh(D)-positive and -negative blood. Erythrocyte membrane vesicles were solubilized in NaDodSO{sub 4}, and a tracer of immunoprecipitated {sup 125}I surface-labeled Rh protein was added. The Rh protein was purified to homogeneity by hydroxylapatite chromatography followed by preparative NaDodSO{sub 4}/PAGE. Approximately 25 nmol of pure Rh protein was recovered from each unit of Rh(D)-positive and -negative blood. Rh protein purified from both Rh phenotypes appeared similar by one-dimensional NaDodSO{sub 4}/PAGE, and the N-terminal amino acid sequences for the first 20 residues were identical. Rh proteins purified from Rh(D)-positive and -negative blood were compared by two-dimensional iodopeptide mapping after {sup 125}I-labeling and {alpha}-chymotrypsin digestion. The peptide maps were very similar. These data indicate that a similar core Rh protein exists in both Rh(D)-positive and -negative erythrocytes, and the Rh proteins from erythrocytes with different Rh phenotypes contain distinct structural polymorphisms.

  17. Human erythrocytes and neuroblastoma cells are in vitro affected by sodium orthovanadate.

    PubMed

    Suwalsky, M; Fierro, P; Villena, F; Aguilar, L F; Sotomayor, C P; Jemiola-Rzeminska, M; Strzalka, K; Gul-Hinc, S; Ronowska, A; Szutowicz, A

    2012-09-01

    Research on biological influence of vanadium has gained major importance because it exerts potent toxic, mutagenic, and genotoxic effects on a wide variety of biological systems. However, hematological toxicity is one of the less studied effects. The lack of information on this issue prompted us to study the structural effects induced on the human erythrocyte membrane by vanadium (V). Sodium orthovanadate was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence in order that orthovanadate interacted with red cell membranes as follows: a) in scanning electron microscopy (SEM) studies it was observed that morphological changes on human erythrocytes were induced; b) fluorescence spectroscopy experiments in isolated unsealed human erythrocyte membranes (IUM) showed that an increase in the molecular dynamics and/or water content at the shallow depth of the lipids glycerol backbone at concentrations as low as 50μM was produced; c) X-ray diffraction studies showed that orthovanadate 0.25-1mM range induced increasing structural perturbation to DMPE; d) somewhat similar effects were observed by differential scanning calorimetry (DSC) with the exception of the fact that DMPC pretransition was shown to be affected; and e) fluorescence spectroscopy experiments performed in DMPC large unilamellar vesicles (LUV) showed that at very low concentrations induced changes in DPH fluorescence anisotropy at 18°C. Additional experiments were performed in mice cholinergic neuroblastoma SN56 cells; a statistically significant decrease of cell viability was observed on orthovanadate in low or moderate concentrations. PMID:22546530

  18. Effects of long-term space flight on erythrocytes and oxidative stress of rodents.

    PubMed

    Rizzo, Angela Maria; Corsetto, Paola Antonia; Montorfano, Gigliola; Milani, Simona; Zava, Stefania; Tavella, Sara; Cancedda, Ranieri; Berra, Bruno

    2012-01-01

    Erythrocyte and hemoglobin losses have been frequently observed in humans during space missions; these observations have been designated as "space anemia". Erythrocytes exposed to microgravity have a modified rheology and undergo hemolysis to a greater extent. Cell membrane composition plays an important role in determining erythrocyte resistance to mechanical stress and it is well known that membrane composition might be influenced by external events, such as hypothermia, hypoxia or gravitational strength variations. Moreover, an altered cell membrane composition, in particular in fatty acids, can cause a greater sensitivity to peroxidative stress, with increase in membrane fragility. Solar radiation or low wavelength electromagnetic radiations (such as gamma rays) from the Earth or the space environment can split water to generate the hydroxyl radical, very reactive at the site of its formation, which can initiate chain reactions leading to lipid peroxidation. These reactive free radicals can react with the non-radical molecules, leading to oxidative damage of lipids, proteins and DNA, etiologically associated with various diseases and morbidities such as cancer, cell degeneration, and inflammation. Indeed, radiation constitutes on of the most important hazard for humans during long-term space flights. With this background, we participated to the MDS tissue-sharing program performing analyses on mice erythrocytes flown on the ISS from August to November 2009. Our results indicate that space flight induced modifications in cell membrane composition and increase of lipid peroxidation products, in mouse erythrocytes. Moreover, antioxidant defenses in the flight erythrocytes were induced, with a significant increase of glutathione content as compared to both vivarium and ground control erythrocytes. Nonetheless, this induction was not sufficient to prevent damages caused by oxidative stress. Future experiments should provide information helpful to reduce the effects

  19. Nectar robbery by a hermit hummingbird: association to floral phenotype and its influence on flowers and network structure.

    PubMed

    Maruyama, Pietro Kiyoshi; Vizentin-Bugoni, Jeferson; Dalsgaard, Bo; Sazima, Ivan; Sazima, Marlies

    2015-07-01

    Interactions between flowers and their visitors span the spectrum from mutualism to antagonism. The literature is rich in studies focusing on mutualism, but nectar robbery has mostly been investigated using phytocentric approaches focused on only a few plant species. To fill this gap, we studied the interactions between a nectar-robbing hermit hummingbird, Phaethornis ruber, and the array of flowers it visits. First, based on a literature review of the interactions involving P. ruber, we characterized the association of floral larceny to floral phenotype. We then experimentally examined the effects of nectar robbing on nectar standing crop and number of visits of the pollinators to the flowers of Canna paniculata. Finally, we asked whether the incorporation of illegitimate interactions into the analysis affects plant-hummingbird network structure. We identified 97 plant species visited by P. ruber and found that P. ruber engaged in floral larceny in almost 30% of these species. Nectar robbery was especially common in flowers with longer corolla. In terms of the effect on C. paniculata, the depletion of nectar due to robbery by P. ruber was associated with decreased visitation rates of legitimate pollinators. At the community level, the inclusion of the illegitimate visits of P. ruber resulted in modifications of how modules within the network were organized, notably giving rise to a new module consisting of P. ruber and mostly robbed flowers. However, although illegitimate visits constituted approximately 9% of all interactions in the network, changes in nestedness, modularity, and network-level specialization were minor. Our results indicate that although a flower robber may have a strong effect on the pollination of a particular plant species, the inclusion of its illegitimate interactions has limited capacity to change overall network structure.

  20. Influence of the lpr environment on the lymph node cell phenotypes in C57BL/6 nubg and nulpr chimeras.

    PubMed Central

    Tiberghien, F; Ceredig, R; Loor, F

    1994-01-01

    Mice homozygous for the lpr gene show a marked lymphoproliferative syndrome. Most T cells which accumulate in their lymphoid organs belong to a fairly unusual subpopulation. Although being CD44+ T cells expressing neither CD4 nor CD8, they are CD3 T-cell receptor (TCR) alpha beta positive and express both Thy-1 and B220, the B-cell form of the CD45 marker. To support engraftment and development of transferred lpr lymphomyeloid cells, athymic recipients must be genetically lpr. While nude/beige (nubg) recipients do not allow the development of any lymphoproliferative syndrome, this is variable in nude/lpr (nulpr) recipients, and the genotypic origin of the proliferating lymphocytes in nulpr recipients is unclear. In this study, the surface phenotype of lymph node cells from nulpr recipients of lpr grafts ([lpr-->nulpr] chimeras) was analysed by flow cytometry, and compared with various chimeras and parental (donor and recipient) strains as controls. Abnormal cells of the lpr type were not detectable either in [lpr-->nubg] chimeras or in [wild-->nubg] controls. Absence of lpr cells was also seen in neonatal lpr thymus-grafted nubg mice engrafted previously with lpr haematopoietic cells. In contrast, a substantial emergence of double-positive B220+ Thy-1+ cells occurred in [lpr-->nulpr] chimeras, together with high levels of CD4+ cells, a substantial fraction of which might express B220. Finally, in thymus-grafted nulpr mice, the levels of B220+ Thy-1+ cells were as high as in lpr mice and there was again an expansion of CD4+ (potentially B220+) cells. Abnormality of the nulpr haemopoietic environment was also shown by the low percentages of T cells, particularly CD8+ cells, in short-lived [wild-->nulpr] chimeras. Taken together, our results underline the differences between the nubg and nulpr environments. PMID:7875735

  1. The influence of abiotic stress and phenotypic plasticity on the distribution of invasive Alternanthera philoxeroides along a riparian zone

    NASA Astrophysics Data System (ADS)

    Pan, Xiaoyun; Geng, Yupeng; Zhang, Wenju; Li, Bo; Chen, Jiakuan

    2006-11-01

    Relatively few studies have compared invasibility and species invasiveness among microhabitats within communities, synchronously. We surveyed the abundance and performance of non-native Alternanthera philoxeroides (Mart.) Griseb. (alligator weed), its co-occurring native congener, Alternanthera sessilis (L.) DC. (sessile joyweed), and other species in a wetland community along a riparian zone in southeast China to test the hypotheses that: i) degree of invasion differs between different types of microhabitats within the community; and ii) microhabitat types that differ in invasibility also differ in soil resource availability or in sediment characteristics likely to affect resource availability; iii) phenotypic plasticity of A. philoxeroides may play a key role in its adaptation to diverse habitats as can be concluded from its extremely low genetic diversity in China. The study riparian zone comprises different types of microhabitats including wet abandoned field, swamp, marsh dunes and gravel dunes. Consistent with these hypotheses, cover of A. philoxeroides was high in abandoned fields (73 ± 2.9%) and swamps (94 ± 1.3%), which had high soil nutrients and water availability. On the contrary, cover of native A. sessilis was relatively high in marsh dunes and grave dunes, which had coarse gravel surfaces, low soil nutrients and low water availability. A. philoxeroides showed greater morphological plasticity in response to habitat variation. In abiotically harsh habitats, stems had limited growth, and were prostrate with weak adventitious roots at nodes, forming thin, scattered patches. In the two richer habitats, the highly branched plants spread over the water or soil surface, supporting dense stronger leaf-bearing stems which grew vertically. The growth pattern of A. sessilis among microhabitats did not exhibit significant variations. These results suggest that morphological plasticity and microhabitat types with high soil resources may facilitate invasions of A

  2. Nectar robbery by a hermit hummingbird: association to floral phenotype and its influence on flowers and network structure.

    PubMed

    Maruyama, Pietro Kiyoshi; Vizentin-Bugoni, Jeferson; Dalsgaard, Bo; Sazima, Ivan; Sazima, Marlies

    2015-07-01

    Interactions between flowers and their visitors span the spectrum from mutualism to antagonism. The literature is rich in studies focusing on mutualism, but nectar robbery has mostly been investigated using phytocentric approaches focused on only a few plant species. To fill this gap, we studied the interactions between a nectar-robbing hermit hummingbird, Phaethornis ruber, and the array of flowers it visits. First, based on a literature review of the interactions involving P. ruber, we characterized the association of floral larceny to floral phenotype. We then experimentally examined the effects of nectar robbing on nectar standing crop and number of visits of the pollinators to the flowers of Canna paniculata. Finally, we asked whether the incorporation of illegitimate interactions into the analysis affects plant-hummingbird network structure. We identified 97 plant species visited by P. ruber and found that P. ruber engaged in floral larceny in almost 30% of these species. Nectar robbery was especially common in flowers with longer corolla. In terms of the effect on C. paniculata, the depletion of nectar due to robbery by P. ruber was associated with decreased visitation rates of legitimate pollinators. At the community level, the inclusion of the illegitimate visits of P. ruber resulted in modifications of how modules within the network were organized, notably giving rise to a new module consisting of P. ruber and mostly robbed flowers. However, although illegitimate visits constituted approximately 9% of all interactions in the network, changes in nestedness, modularity, and network-level specialization were minor. Our results indicate that although a flower robber may have a strong effect on the pollination of a particular plant species, the inclusion of its illegitimate interactions has limited capacity to change overall network structure. PMID:25740333

  3. Influence of blood pressure profile on frailty phenotype in community-dwelling elders in Brazil - FIBRA study.

    PubMed

    Fattori, A; Santimaria, M R; Alves, R M A; Guariento, M E; Neri, A L

    2013-01-01

    Frailty is a clinical condition associated with pathological aging and biological vulnerability. In the spectrum of events related to frailty, aging of the cardiocirculatory system and abnormalities in arterial blood pressure (BP) partly explain the changes in tissue perfusion and, potentially, the decrease in physiological reserves. This study investigated the relationship between BP levels, systemic arterial hypertension (SAH) and the frailty phenotype by analyzing frailty criteria in a cross-sectional model into the FIBRA network, a populational sample of community-dwelling elders in Southeastern Brazil. Study participants with ≥65 years were selected by probabilistic sampling of residents in the urban area of the municipality of Campinas (n=900). Considering frailty as a whole and the difference between genders, there was a greater proportion of frail or pre-frail individuals among women than men. Analysis of individual frailty criteria showed that weight loss and fatigue were more common among women (18.3% vs. 12.5%, p=0.034 and 22.5% vs. 11.9%, p<0.001, respectively). Comparison of individuals with or without SAH failed to reveal any differences related to frailty criteria. Nevertheless, averages of diastolic blood pressure (DBP) and mean arterial blood pressure values were lower among elderly individuals with reduced grip strength, physical activity and the frailty classification as a whole (OR 0.986, IC 0.975-0.997) (for every 1 mmHg reduction in MBP values, the likelihood of being frail increased 1.4%). Our findings corroborate the relationship between BP values and frailty in the elderly and contribute to an understanding of the pathophysiological mechanisms of the syndrome.

  4. [Influence of genetic and phenotypical factors on the efficiency of the vaccination of young children against diphtheria and measles].

    PubMed

    Gordeeva, L A; Shabaldin, A V; Semenova, E M; Glushkov, A N

    2006-01-01

    The child's sex was shown to influence the character of antibody formation only after immunization against diphtheria with live measles vaccine: girls exhibited stronger reaction to vaccination than boys. Children of different gender were found to have characteristic HLA DR markers of humoral immune response to diphtheria toxoid and measles vaccine. HLA DR7 proved to be the marker of low production of antibodies to diphtheria toxoid and measles vaccine in boys.

  5. A heterogeneity of the pheasant (Phasianus colchicus L.) erythrocyte histone H1 subtype H5.

    PubMed

    Kowalski, Andrzej

    2016-01-01

    In a previous work (Górnicka-Michalska et al. (1998)), an occurrence of genetic variants in the chicken erythrocyte histone H5 has been presented. Here, the pheasant histone H5 heterogeneity is characterized to verify if the interspecies variability of this protein is caused by the analogous determinants. During screening histone H1 preparations isolated from the pheasant erythrocytes, histone H5 was identified as differently located in the electrophoretic gels. According to the rate of electrophoretic migration, two histone H5 phenotypes (H5a and H5b) possessing similar quantitative proportion (P>0.05) were distinguished. A rare phenotype H5a (frequency 0.26) migrating faster in the SDS-PAGE was low mobile in the AU-PAGE, in contrast to the frequent phenotype H5b (frequency 0.74) that moved slowly in the SDS-PAGE and roamed faster in the AU-PAGE. The electrophoretic properties of histone H5 phenotypes may reflect disparities in their net charge and molecular weight. Peptide maps of histone H5 phenotypes, obtained by partial chemical cleavage (NBS) and limited enzymatic digestion (α-chymotrypsin), revealed their C-peptides possessing the same electrophoretic mobility and the N-peptides having variable rate of the electrophoretic migration. Based on this, the identified phenotypic variation seems to be determined by a histone H5 phenotype-specific amino acid sequence region situated in the N-terminal portion of its molecule. According to the identified varied sequence stretches, histone H5 phenotype may induce specific effects related to the organization and/or function of the pheasant chromatin.

  6. Transporting of sodium and calcium cation in erythrocyte in patients with essential hypertension.

    PubMed

    Zhu, Z M; Song, K Q; Liu, G Y; Li, Y R

    1990-02-01

    The sodium and calcium cation transport in erythrocyte and their influencing factors were studied in essential hypertensive (EH) patients. The result showed that plasma sodium pump inhibitor, endogenous digitalis-like compound (EDLC), rose in some patients and sodium pump was depressed in the others, but there were no parallel links between EDLC and sodium pump. The patients with normal sodium pump have mainly shown a decrease of their maximal CA++ pump activity and calmodulin (CaM) content in erythrocyte. It indicated that there might be different types of ion transporting defect in EH, and the abnormalities of these cation transports might be an important pathogenesis in EH. PMID:2167817

  7. Protective effects of bacterial osmoprotectant ectoine on bovine erythrocytes subjected to staphylococcal alpha-haemolysin.

    PubMed

    Bownik, Adam; Stępniewska, Zofia

    2015-06-01

    Ectoine (ECT) is a bacterial compatible solute with documented protective action however no data are available on its effects on various cells against bacterial toxins. Therefore, we determined the in vitro influence of ECT on bovine erythrocytes subjected to staphylococcal α-haemolysin (HlyA). The cells exposed to HlyA alone showed a distinct haemolysis and reduced glutathione (GSH)/oxidised glutathione (GSSG) level, however the toxic effects were attenuated in the combinations of HlyA + ECT suggesting ECT-induced protection of erythrocytes from HlyA.

  8. Conceptual and Data-based Investigation of Genetic Influences and Brain Asymmetry: A Twin Study of Multiple Structural Phenotypes

    PubMed Central

    Eyler, Lisa T.; Vuoksimaa, Eero; Panizzon, Matthew S.; Fennema-Notestine, Christine; Neale, Michael C.; Chen, Chi-Hua; Jak, Amy; Franz, Carol E.; Lyons, Michael J.; Thompson, Wesley K.; Spoon, Kelly M.; Fischl, Bruce; Dale, Anders M.; Kremen, William S.

    2014-01-01

    Right–left regional cerebral differences are a feature of the human brain linked to functional abilities, aging, and neuro-developmental and mental disorders. The role of genetic factors in structural asymmetry has been incompletely studied. We analyzed data from 515 individuals (130 monozygotic twin pairs, 97 dizygotic pairs, and 61 unpaired twins) from the Vietnam Era Twin Study of Aging to answer three questions about genetic determinants of brain structural asymmetry: First, does the magnitude of heritability differ for homologous regions in each hemisphere? Despite adequate power to detect regional differences, heritability estimates were not significantly larger in one hemisphere versus the other, except left > right inferior lateral ventricle heritability. Second, do different genetic factors influence left and right hemisphere size in homologous regions? Inter-hemispheric genetic correlations were high and significant; in only two subcortical regions (pallidum and accumbens) did the estimate statistically differ from 1.0. Thus, there was little evidence for different genetic influences on left and right hemisphere regions. Third, to what extent do genetic factors influence variability in left–right size differences? There was no evidence that variation in asymmetry (i.e., the size difference) of left and right homologous regions was genetically determined, except in pallidum and accumbens. Our findings suggest that genetic factors do not play a significant role in determining individual variation in the degree of regional cortical size asymmetries measured with MRI, although they may do so for volume of some subcortical structures. Despite varying interpretations of existing left–right, we view the present results as consistent with previous findings. PMID:24283492

  9. Metabolism of acetylcholine in human erythrocytes

    SciTech Connect

    Chapman, E.S.

    1990-01-01

    In order to examine the possible role of erythrocyte acetylcholinesterase in the maintenance of membrane phospholipid content and membrane fluidity, experiments were performed to monitor the activity of the enzyme and follow the fate of one of its hydrolytic products, choline. Intact human erythrocytes were incubated with acetylcholine (choline methyl-{sup 14}C). The incubation resulted in the hydrolysis of acetylcholine to acetate and choline; the reaction was catalyzed by membrane acetylcholinesterase. The studies demonstrate the further metabolism of choline. Experiments were carried out to determine rate of hydrolysis of acetylcholine, uptake of choline, identification of intracellular metabolites of choline, and identification of radiolabeled membrane components. Erythrocytes at a 25% hematocrit were incubated in an isoosmotic bicarbonate buffer pH 7.4, containing glucose, adenosine, streptomycin and penicillin with 0.3 {mu}Ci of acetylcholine (choline methyl-{sup 14}C), for 24 hours. Aliquots of the erythrocyte suspension were taken throughout for analysis. Erythrocytes were washed free of excess substrate, lysed, and the hemolysate was extracted for choline and its metabolites. Blank samples containing incubation buffer and radiolabeled acetylcholine only, and erythrocyte hemolysate extracts were analyzed for choline content, the difference between blank samples and hemolysate extracts was the amount of choline originating from acetylcholine and attributable to acetylcholinesterase activity. The conversion of choline to {sup 14}C-betaine is noted after several minutes of incubation; at 30 minutes, more than 80% of {sup 14}C-choline is taken up and after several hours, detectable levels of radiolabeled S-adenosylmethionine were present in the hemolysate extract.

  10. Faciobrachial dystonic seizures: the influence of immunotherapy on seizure control and prevention of cognitive impairment in a broadening phenotype.

    PubMed

    Irani, Sarosh R; Stagg, Charlotte J; Schott, Jonathan M; Rosenthal, Clive R; Schneider, Susanne A; Pettingill, Philippa; Pettingill, Rosemary; Waters, Patrick; Thomas, Adam; Voets, Natalie L; Cardoso, Manuel J; Cash, David M; Manning, Emily N; Lang, Bethan; Smith, Shelagh J M; Vincent, Angela; Johnson, Michael R

    2013-10-01

    months in six cases. Voltage-gated potassium channel-complex antibodies persisted in the four cases with relapses of faciobrachial dystonic seizures during corticosteroid withdrawal. Time to recovery of baseline function was positively correlated with time to immunotherapy (r = 0.74; P = 0.03) but not time to anti-epileptic drug administration (r = 0.55; P = 0.10). Of 10 cases, the eight cases who received anti-epileptic drugs (n = 3) or no treatment (n = 5) all developed cognitive impairment. By contrast, the two who did not develop cognitive impairment received immunotherapy to treat their faciobrachial dystonic seizures (P = 0.02). In eight cases without clinical magnetic resonance imaging evidence of hippocampal signal change, cross-sectional volumetric magnetic resonance imaging post-recovery, after accounting for age and head size, revealed cases (n = 8) had smaller brain volumes than healthy controls (n = 13) (P < 0.001). In conclusion, faciobrachial dystonic seizures can be prospectively identified as a form of epilepsy with an expanding phenotype. Immunotherapy is associated with excellent control of the frequently anti-epileptic drug refractory seizures, hastens time to recovery, and may prevent the subsequent development of cognitive impairment observed in this study.

  11. Malformation of true bug (Heteroptera): a phenotype field study on the possible influence of artificial low-level radioactivity.

    PubMed

    Hesse-Honegger, Cornelia; Wallimann, Peter

    2008-04-01

    The results of extensive field studies on the malformation of Western European true bugs (Heteroptera) are reviewed. More than 16,000 individuals were collected over two decades, and subjected to detailed visual inspection. Various types of disturbances were found and illustrated in detail. Depending on country, region, as well as local influences, severe disturbances and high degrees of malformation were noticed, especially in the sphere of nuclear-power installations in Switzerland (Aargau), France (La Hague), and Germany (Gundremmingen). Malformation reached values as high as 22 and 30% for morphological (MD) and total disturbance (TD), respectively. This is far above the values expected for natural populations (ca. 1%) or those determined for true bugs living in biotopes considered as relatively 'intact' (1-3%). A detailed chi-square test of the malformation data obtained for 650 true bugs from 13 collection sites near the nuclear-reprocessing plant La Hague showed a highly significant correlation (p=0.003) between malformation and wind exposure/local topography. Similar observations were made for other study sites. Currently, our data are best rationalized by assuming a direct influence between the release of anthropogenic radionuclides such as tritium ((3)H), carbon-14 ((14)C), or iodine-131 ((131)I), constantly emitted by nuclear-power and nuclear-reprocessing plants, as well as by Chernobyl and bomb-testing fallout, which is rich in caesium-137 ((137)Cs) and other long-lived noxious isotopes that have entered the food chain. The present work supports the growing evidence that low-level radiation, especially in the form of randomly scattered 'hot' alpha- and beta-particles, mainly transported via aerosols, puts a heavy burden on the biosphere in general, and on true bugs in particular. These insects could, thus, serve as sensitive 'bio-indicators' for future studies.

  12. Influence of space flight conditions on phenotypes and function of nephritic immune cells of swordtail fish ( Xiphophorus helleri)

    NASA Astrophysics Data System (ADS)

    Piepenbreier, K.; Renn, J.; Fischer, R.; Goerlich, R.

    2006-01-01

    During space fights, animals and astronauts have to live and act under unusual environmental conditions characterised by reduced gravity. Due to interactions with several physiological systems, the immune system is sensitive to endogenous and exogenous influences. The present study provides the first data of parameters of the defence system, namely differential haemogram and spontaneous cell proliferation activity of nephritic tissue as well as phagocytosis activity of isolated nephritic phagocytes, in teleost fish after 9 days (STS-89) and 16 days (STS-90) of space flight. The artificial aquatic ecosystem C.E.B.A.S. (Closed Equilibrated Biological Aquatic System) was the habitat of swordtail fish ( Xiphophorus helleri) during space flights and for ground controls. No statistically significant differences were observed between fish after space flights and ground controls either after 9 or 16 days. Additionally, all values of the space flight experiments remained within the physiological normal area. However, in comparison to the values of fish that were kept in aquaria as ground controls, the environmental conditions of some C.E.B.A.S. ground experiments showed a decrease of monocytes and lymphocytes as well as inhibition of the activity of phagocytosis and spontaneous cell proliferation. Swordtails from C.E.B.A.S. ground experiments showed typical symptoms of a stress reaction, namely a decrease of monocytes and lymphocytes and an inhibition of phagocytosis activity. These results indicate that short-term space flights of 9 and 16 days have no effects on the immune system of the swordtails, whereas specific environmental conditions such as those found in the C.E.B.A.S. module during the experiments have the potential to influence defence parameters.

  13. Isoforms of Pax5 and co-regulation of T- and B-cells associated genes influence phenotypic traits of ascetic cells causing Dalton's lymphoma.

    PubMed

    Bharti, Brij; Mishra, Rajnikant

    2011-12-01

    The Pax5 and its isoforms influence proliferation of B- and T-cells, during development and oncogenesis but molecular mechanism and host-tumor relationship is not clear. This report describes status of Pax5 isoforms and co-regulation of molecular markers of ascite cells causing Dalton's lymphoma in murine. Higher expressions of Pax5, CD19, CD3, Ras and Raf were observed in DLA cells. The levels of transcripts as well as p53 protein were also higher in DLA cells. The transcript of p53 from DLA cells was a variant of p53 having deletion of 50bp as compared to control. On annotation, it reflects transformation related protein p53 pseudogene mRNA. Lower level of superoxide dismutase (SOD) indicates oxidative stress and higher level of LDH5 in DLA cells reflects hypoxia in cancerous condition. The expression of Pax5d/e isoforms in DLA cells suggests presence of resting B-cells. Thus, isoforms of Pax5 and co-regulation of T- and B-cells associated genes influence phenotypic traits of ascetic cells causing Dalton's lymphoma. PMID:21854813

  14. Erythrocyte sedimentation rate and C-reactive protein.

    PubMed

    Harrison, Michael

    2015-06-01

    C-reactive protein is a better indicator of inflammation than the erythrocyte sedimentation rate. It is more sensitive and responds more quickly to changes in the clinical situation. False negative and false positive results are more common when measuring the erythrocyte sedimentation rate. Renal disease, female sex and older age increase the erythrocyte sedimentation rate. The erythrocyte sedimentation rate has value in detecting low-grade bone infection, and in monitoring some patients with systemic lupus erythematosus.

  15. Gender as a Modifying Factor Influencing Myotonic Dystrophy Type 1 Phenotype Severity and Mortality: A Nationwide Multiple Databases Cross-Sectional Observational Study

    PubMed Central

    Hamroun, Dalil; Varet, Hugo; Fabbro, Marianne; Rougier, Felix; Amarof, Khadija; Arne Bes, Marie-Christine; Bedat-Millet, Anne-Laure; Behin, Anthony; Bellance, Remi; Bouhour, Françoise; Boutte, Celia; Boyer, François; Campana-Salort, Emmanuelle; Chapon, Françoise; Cintas, Pascal; Desnuelle, Claude; Deschamps, Romain; Drouin-Garraud, Valerie; Ferrer, Xavier; Gervais-Bernard, Helene; Ghorab, Karima; Laforet, Pascal; Magot, Armelle; Magy, Laurent; Menard, Dominique; Minot, Marie-Christine; Nadaj-Pakleza, Aleksandra; Pellieux, Sybille; Pereon, Yann; Preudhomme, Marguerite; Pouget, Jean; Sacconi, Sabrina; Sole, Guilhem; Stojkovich, Tanya; Tiffreau, Vincent; Urtizberea, Andoni; Vial, Christophe; Zagnoli, Fabien; Caranhac, Gilbert; Bourlier, Claude; Riviere, Gerard; Geille, Alain; Gherardi, Romain K.; Eymard, Bruno; Puymirat, Jack; Katsahian, Sandrine; Bassez, Guillaume

    2016-01-01

    Background Myotonic Dystrophy type 1 (DM1) is one of the most heterogeneous hereditary disease in terms of age of onset, clinical manifestations, and severity, challenging both medical management and clinical trials. The CTG expansion size is the main factor determining the age of onset although no factor can finely predict phenotype and prognosis. Differences between males and females have not been specifically reported. Our aim is to study gender impact on DM1 phenotype and severity. Methods We first performed cross-sectional analysis of main multiorgan clinical parameters in 1409 adult DM1 patients (>18y) from the DM-Scope nationwide registry and observed different patterns in males and females. Then, we assessed gender impact on social and economic domains using the AFM-Téléthon DM1 survey (n = 970), and morbidity and mortality using the French National Health Service Database (n = 3301). Results Men more frequently had (1) severe muscular disability with marked myotonia, muscle weakness, cardiac, and respiratory involvement; (2) developmental abnormalities with facial dysmorphism and cognitive impairment inferred from low educational levels and work in specialized environments; and (3) lonely life. Alternatively, women more frequently had cataracts, dysphagia, digestive tract dysfunction, incontinence, thyroid disorder and obesity. Most differences were out of proportion to those observed in the general population. Compared to women, males were more affected in their social and economic life. In addition, they were more frequently hospitalized for cardiac problems, and had a higher mortality rate. Conclusion Gender is a previously unrecognized factor influencing DM1 clinical profile and severity of the disease, with worse socio-economic consequences of the disease and higher morbidity and mortality in males. Gender should be considered in the design of both stratified medical management and clinical trials. PMID:26849574

  16. Studies of the pathogenesis of anemia of inflammation: erythrocyte survival

    SciTech Connect

    Weiss, D.J.; Krehbiel, J.D.

    1983-10-01

    Erythrocyte survival was investigated in healthy cats and in cats with sterile abscesses. Erythrocyte survival time in cats with sterile abscesses was found to be significantly reduced. The erythrocyte destruction appeared to be the major factor in the early stages of anemia of inflammation.

  17. CR1 on erythrocytes of Brazilian systemic lupus erythematosus patients: the influence of disease activity on expression and ability of this receptor to bind immune complexes opsonized with complement from normal human serum.

    PubMed

    Marzocchi-Machado, C M; Alves, C M O S; Azzolini, A E C S; Polizello, A C M; Carvalho, I F; Lucisano-Valim, Y M

    2005-12-01

    Hypocomplementaemia and low expression of CR1 on erythrocytes (E) of patients with systemic lupus erythematosus (SLE) are associated with defective clearance of circulating immune complexes (IC) and so they may have pathogenic significance. Here, we investigated whether the reduced CR1/E in SLE patients per se might affect the binding of IC to CR1/E. First, we analysed the expression of CR1 on E of active (n=30) and inactive (n=34) SLE patients using a FITC-conjugated mouse anti-CR1 monoclonal antibody E11 and flow cytometry. Both groups of patients had a significantly reduced CR1/E expression compared with healthy controls (n=40). It was also observed that the number of E bearing CR1 was reduced in both groups of SLE patients studied. Second, we determined the functional activity of CR1/E by measuring the binding to E of FITC-bovine serum albumin (BSA)/rabbit anti-BSA complexes, formed at equivalence, which were opsonized with complement from normal human serum (NHS). On the other hand, we did not find differences between the patient and control groups in the ability of E to bind IC/NHS. There was also a positive correlation between the CR1/E expression and the number of E bearing CR1 in control and inactive SLE groups, which was not observed in the group of active SLE patients. Considering the involvement of low levels of complement and CR1/E expression on complex processing, in this in vitro model the results show that an effective coating of the complexes with complement is sufficient to bind them preferentially to CR1 over normal levels of receptor expression.

  18. Stressful Presentations: Mild Cold Stress in Laboratory Mice Influences Phenotype of Dendritic Cells in Naïve and Tumor-Bearing Mice

    PubMed Central

    Kokolus, Kathleen M.; Spangler, Haley M.; Povinelli, Benjamin J.; Farren, Matthew R.; Lee, Kelvin P.; Repasky, Elizabeth A.

    2013-01-01

    The ability of dendritic cells (DCs) to stimulate and regulate T cells is critical to effective anti-tumor immunity. Therefore, it is important to fully recognize any inherent factors which may influence DC function under experimental conditions, especially in laboratory mice since they are used so heavily to model immune responses. The goals of this report are to 1) briefly summarize previous work revealing how DCs respond to various forms of physiological stress and 2) to present new data highlighting the potential for chronic mild cold stress inherent to mice housed at the required standard ambient temperatures to influence baseline DCs properties in naïve and tumor-bearing mice. As recent data from our group shows that CD8+ T cell function is significantly altered by chronic mild cold stress and since DC function is crucial for CD8+ T cell activation, we wondered whether housing temperature may also be influencing DC function. Here we report that there are several significant phenotypical and functional differences among DC subsets in naïve and tumor-bearing mice housed at either standard housing temperature or at a thermoneutral ambient temperature, which significantly reduces the extent of cold stress. The new data presented here strongly suggests that, by itself, the housing temperature of mice can affect fundamental properties and functions of DCs. Therefore differences in basal levels of stress due to housing should be taken into consideration when interpreting experiments designed to evaluate the impact of additional variables, including other stressors on DC function. PMID:24575090

  19. Erythrocyte survival in sheep exposed to ozone

    SciTech Connect

    Moore, G.S.; Calabrese, E.J.; Labato, F.J.

    1981-07-01

    Erythrocyte survival studies in the Dorset ewe using chromium 51 were performed. The purpose of the study was to determine if ozone exposure produces decreased cell survival which may be the result of premature erythrocyte aging. This strain of sheep has an erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity that is very low, being comparable to human A-variants with G6PD deficiency. Ozone exposure may produce hemolytic effects in G6PD deficients more readily than in erythrocytes with normal activity. A decrease in hematocrit was observed in the ozone exposed groups. With respect to red cell destruction, ozone does not appear to act immediately, but rather there appears to be a delayed effect. At 0.25 ppM ozone, the group reached the 50% remaining level an average of 1 day sooner than the control group. There was no significant difference between control and exposed groups at the 0.50 ppM and 0.70 ppM levels. Also, the results demonstrate a net decrease in hematocrit which is greater for 0.25 ppM ozone than any other exposure level. (RJC)

  20. Brucella melitensis invades murine erythrocytes during infection.

    PubMed

    Vitry, Marie-Alice; Hanot Mambres, Delphine; Deghelt, Michaël; Hack, Katrin; Machelart, Arnaud; Lhomme, Frédéric; Vanderwinden, Jean-Marie; Vermeersch, Marjorie; De Trez, Carl; Pérez-Morga, David; Letesson, Jean-Jacques; Muraille, Eric

    2014-09-01

    Brucella spp. are facultative intracellular Gram-negative coccobacilli responsible for brucellosis, a worldwide zoonosis. We observed that Brucella melitensis is able to persist for several weeks in the blood of intraperitoneally infected mice and that transferred blood at any time point tested is able to induce infection in naive recipient mice. Bacterial persistence in the blood is dramatically impaired by specific antibodies induced following Brucella vaccination. In contrast to Bartonella, the type IV secretion system and flagellar expression are not critically required for the persistence of Brucella in blood. ImageStream analysis of blood cells showed that following a brief extracellular phase, Brucella is associated mainly with the erythrocytes. Examination by confocal microscopy and transmission electron microscopy formally demonstrated that B. melitensis is able to invade erythrocytes in vivo. The bacteria do not seem to multiply in erythrocytes and are found free in the cytoplasm. Our results open up new areas for investigation and should serve in the development of novel strategies for the treatment or prophylaxis of brucellosis. Invasion of erythrocytes could potentially protect the bacterial cells from the host's immune response and hamper antibiotic treatment and suggests possible Brucella transmission by bloodsucking insects in nature.

  1. Brucella melitensis Invades Murine Erythrocytes during Infection

    PubMed Central

    Vitry, Marie-Alice; Hanot Mambres, Delphine; Deghelt, Michaël; Hack, Katrin; Machelart, Arnaud; Lhomme, Frédéric; Vanderwinden, Jean-Marie; Vermeersch, Marjorie; De Trez, Carl; Pérez-Morga, David; Letesson, Jean-Jacques

    2014-01-01

    Brucella spp. are facultative intracellular Gram-negative coccobacilli responsible for brucellosis, a worldwide zoonosis. We observed that Brucella melitensis is able to persist for several weeks in the blood of intraperitoneally infected mice and that transferred blood at any time point tested is able to induce infection in naive recipient mice. Bacterial persistence in the blood is dramatically impaired by specific antibodies induced following Brucella vaccination. In contrast to Bartonella, the type IV secretion system and flagellar expression are not critically required for the persistence of Brucella in blood. ImageStream analysis of blood cells showed that following a brief extracellular phase, Brucella is associated mainly with the erythrocytes. Examination by confocal microscopy and transmission electron microscopy formally demonstrated that B. melitensis is able to invade erythrocytes in vivo. The bacteria do not seem to multiply in erythrocytes and are found free in the cytoplasm. Our results open up new areas for investigation and should serve in the development of novel strategies for the treatment or prophylaxis of brucellosis. Invasion of erythrocytes could potentially protect the bacterial cells from the host's immune response and hamper antibiotic treatment and suggests possible Brucella transmission by bloodsucking insects in nature. PMID:25001604

  2. Electrophoretic mobilities of erythrocytes in various buffers

    NASA Technical Reports Server (NTRS)

    Plank, L. D.; Kunze, M. E.; Todd, P. W.

    1985-01-01

    The calibration of space flight equipment depends on a source of standard test particles, this test particle of choice is the fixed erythrocyte. Erythrocytes from different species have different electrophoretic mobilities. Electrophoretic mobility depends upon zeta potential, which, in turn depends upon ionic strength. Zeta potential decreases with increasing ionic strength, so cells have high electrophoretic mobility in space electrophoresis buffers than in typical physiological buffers. The electrophoretic mobilities of fixed human, rat, and rabbit erythrocytes in 0.145 M salt and buffers of varying ionic strength, temperature, and composition, to assess the effects of some of the unique combinations used in space buffers were characterized. Several effects were assessed: glycerol or DMSO (dimethylsulfoxide) were considered for use as cryoprotectants. The effect of these substances on erythrocyte electrophoretic mobility was examined. The choice of buffer depended upon cell mobility. Primary experiments with kidney cells established the choice of buffer and cryoprotectant. A nonstandard temperature of EPM in the suitable buffer was determined. A loss of ionic strength control occurs in the course of preparing columns for flight, the effects of small increases in ionic strength over the expected low values need to be evaluated.

  3. Erythrocyte-binding antigen 175 mediates invasion in Plasmodium falciparum utilizing sialic acid-dependent and -independent pathways

    PubMed Central

    Duraisingh, Manoj T.; Maier, Alexander G.; Triglia, Tony; Cowman, Alan F.

    2003-01-01

    The Plasmodium falciparum erythrocyte-binding antigen 175 (EBA-175) is a ligand for merozoite invasion into human erythrocytes that binds to glycophorin A in a sialic acid-dependent manner. P. falciparum strain W2mef depends on sialic acid for invasion of erythrocytes, whereas 3D7 is sialic acid-independent. We generated parasites that lack expression or express truncated forms of EBA-175 in W2mef and 3D7. Lack of EBA-175 expression in W2mef parasites was associated with a switch to sialic acid-independent invasion. 3D7 parasites lacking expression of EBA-175 showed no alteration in their ability to utilize sialic acid-independent pathways. Strikingly, both W2mef and 3D7 parasites lacking EBA-175 expression invaded chymotrypsin-treated erythrocytes inefficiently compared with the parental lines. This loss of function suggests that the EBA-175/glycophorin A ligand–receptor interaction is the major chymotrypsin-resistant invasion pathway. Parasite lines with truncated EBA-175 had invasion phenotypes equivalent to parasites lacking expression of EBA-175. The EBA-175 ligand is functional in erythrocyte invasion by merozoites that utilize either sialic acid-dependent or -independent invasion pathways. This finding suggests a model where a minimal affinity supplied by multiple ligand–receptor interactions is required for successful invasion and has implications for EBA-175 as a malaria vaccine candidate. PMID:12672957

  4. Erythrocyte shape abnormalities, membrane oxidative damage, and β-actin alterations: an unrecognized triad in classical autism.

    PubMed

    Ciccoli, Lucia; De Felice, Claudio; Paccagnini, Eugenio; Leoncini, Silvia; Pecorelli, Alessandra; Signorini, Cinzia; Belmonte, Giuseppe; Guerranti, Roberto; Cortelazzo, Alessio; Gentile, Mariangela; Zollo, Gloria; Durand, Thierry; Valacchi, Giuseppe; Rossi, Marcello; Hayek, Joussef

    2013-01-01

    Autism spectrum disorders (ASDs) are a complex group of neurodevelopment disorders steadily rising in frequency and treatment refractory, where the search for biological markers is of paramount importance. Although red blood cells (RBCs) membrane lipidomics and rheological variables have been reported to be altered, with some suggestions indicating an increased lipid peroxidation in the erythrocyte membrane, to date no information exists on how the oxidative membrane damage may affect cytoskeletal membrane proteins and, ultimately, RBCs shape in autism. Here, we investigated RBC morphology by scanning electron microscopy in patients with classical autism, that is, the predominant ASDs phenotype (age range: 6-26 years), nonautistic neurodevelopmental disorders (i.e., "positive controls"), and healthy controls (i.e., "negative controls"). A high percentage of altered RBCs shapes, predominantly elliptocytes, was observed in autistic patients, but not in both control groups. The RBCs altered morphology in autistic subjects was related to increased erythrocyte membrane F2-isoprostanes and 4-hydroxynonenal protein adducts. In addition, an oxidative damage of the erythrocyte membrane β-actin protein was evidenced. Therefore, the combination of erythrocyte shape abnormalities, erythrocyte membrane oxidative damage, and β-actin alterations constitutes a previously unrecognized triad in classical autism and provides new biological markers in the diagnostic workup of ASDs.

  5. A perforin-like protein mediates disruption of the erythrocyte membrane during egress of Plasmodium berghei male gametocytes.

    PubMed

    Deligianni, Elena; Morgan, Rhiannon N; Bertuccini, Lucia; Wirth, Christine C; Silmon de Monerri, Natalie C; Spanos, Lefteris; Blackman, Michael J; Louis, Christos; Pradel, Gabriele; Siden-Kiamos, Inga

    2013-08-01

    Successful gametogenesis of the malaria parasite depends on egress of the gametocytes from the erythrocytes within which they developed. Egress entails rupture of both the parasitophorous vacuole membrane and the erythrocyte plasma membrane, and precedes the formation of the motile flagellated male gametes in a process called exflagellation. We show here that egress of the male gametocyte depends on the function of a perforin-like protein, PPLP2. A mutant of Plasmodium berghei lacking PPLP2 displayed abnormal exflagellation; instead of each male gametocyte forming eight flagellated gametes, it produced gametocytes with only one, shared thicker flagellum. Using immunofluorescence and transmission electron microscopy analysis, and phenotype rescue with saponin or a pore-forming toxin, we conclude that rupture of the erythrocyte membrane is blocked in the mutant. The parasitophorous vacuole membrane, on the other hand, is ruptured normally. Some mutant parasites are still able to develop in the mosquito, possibly because the vigorous motility of the flagellated gametes eventually leads to escape from the persisting erythrocyte membrane. This is the first example of a perforin-like protein in Plasmodium parasites having a role in egress from the host cell and the first parasite protein shown to be specifically required for erythrocyte membrane disruption during egress.

  6. α2-Macroglobulin Can Crosslink Multiple Plasmodium falciparum Erythrocyte Membrane Protein 1 (PfEMP1) Molecules and May Facilitate Adhesion of Parasitized Erythrocytes.

    PubMed

    Stevenson, Liz; Laursen, Erik; Cowan, Graeme J; Bandoh, Betty; Barfod, Lea; Cavanagh, David R; Andersen, Gregers R; Hviid, Lars

    2015-07-01

    Rosetting, the adhesion of Plasmodium falciparum-infected erythrocytes to uninfected erythrocytes, involves clonal variants of the parasite protein P. falciparum erythrocyte membrane protein 1 (PfEMP1) and soluble serum factors. While rosetting is a well-known phenotypic marker of parasites associated with severe malaria, the reason for this association remains unclear, as do the molecular details of the interaction between the infected erythrocyte (IE) and the adhering erythrocytes. Here, we identify for the first time a single serum factor, the abundant serum protease inhibitor α2-macroglobulin (α2M), which is both required and sufficient for rosetting mediated by the PfEMP1 protein HB3VAR06 and some other rosette-mediating PfEMP1 proteins. We map the α2M binding site to the C terminal end of HB3VAR06, and demonstrate that α2M can bind at least four HB3VAR06 proteins, plausibly augmenting their combined avidity for host receptors. IgM has previously been identified as a rosette-facilitating soluble factor that acts in a similar way, but it cannot induce rosetting on its own. This is in contrast to α2M and probably due to the more limited cross-linking potential of IgM. Nevertheless, we show that IgM works synergistically with α2M and markedly lowers the concentration of α2M required for rosetting. Finally, HB3VAR06+ IEs share the capacity to bind α2M with subsets of genotypically distinct P. falciparum isolates forming rosettes in vitro and of patient parasite isolates ex vivo. Together, our results are evidence that P. falciparum parasites exploit α2M (and IgM) to expand the repertoire of host receptors available for PfEMP1-mediated IE adhesion, such as the erythrocyte carbohydrate moieties that lead to formation of rosettes. It is likely that this mechanism also affects IE adhesion to receptors on vascular endothelium. The study opens opportunities for broad-ranging immunological interventions targeting the α2M--(and IgM-) binding domains of PfEMP1

  7. In-Depth, Label-Free Analysis of the Erythrocyte Cytoplasmic Proteome in Diamond Blackfan Anemia Identifies a Unique Inflammatory Signature.

    PubMed

    Pesciotta, Esther N; Lam, Ho-Sun; Kossenkov, Andrew; Ge, Jingping; Showe, Louise C; Mason, Philip J; Bessler, Monica; Speicher, David W

    2015-01-01

    Diamond Blackfan Anemia (DBA) is a rare, congenital erythrocyte aplasia that is usually caused by haploinsufficiency of ribosomal proteins due to diverse mutations in one of several ribosomal genes. A striking feature of this disease is that a range of different mutations in ribosomal proteins results in similar disease phenotypes primarily characterized by erythrocyte abnormalities and macrocytic anemia, while most other cell types in the body are minimally affected. Previously, we analyzed the erythrocyte membrane proteomes of several DBA patients and identified several proteins that are not typically associated with this cell type and that suggested inflammatory mechanisms contribute to the pathogenesis of DBA. In this study, we evaluated the erythrocyte cytosolic proteome of DBA patients through in-depth analysis of hemoglobin-depleted erythrocyte cytosols. Simple, reproducible, hemoglobin depletion using nickel columns enabled in-depth analysis of over 1000 cytosolic erythrocyte proteins with only moderate total analysis time per proteome. Label-free quantitation and statistical analysis identified 29 proteins with significantly altered abundance levels in DBA patients compared to matched healthy control donors. Proteins that were significantly increased in DBA erythrocyte cytoplasms included three proteasome subunit beta proteins that make up the immunoproteasome and proteins induced by interferon-γ such as n-myc interactor and interferon-induced 35 kDa protein [NMI and IFI35 respectively]. Pathway analysis confirmed the presence of an inflammatory signature in erythrocytes of DBA patients and predicted key upstream regulators including mitogen activated kinase 1, interferon-γ, tumor suppressor p53, and tumor necrosis factor. These results show that erythrocytes in DBA patients are intrinsically different from those in healthy controls which may be due to an inflammatory response resulting from the inherent molecular defect of ribosomal protein

  8. In-Depth, Label-Free Analysis of the Erythrocyte Cytoplasmic Proteome in Diamond Blackfan Anemia Identifies a Unique Inflammatory Signature

    PubMed Central

    Pesciotta, Esther N.; Lam, Ho-Sun; Kossenkov, Andrew; Ge, Jingping; Showe, Louise C.; Mason, Philip J.; Bessler, Monica; Speicher, David W.

    2015-01-01

    Diamond Blackfan Anemia (DBA) is a rare, congenital erythrocyte aplasia that is usually caused by haploinsufficiency of ribosomal proteins due to diverse mutations in one of several ribosomal genes. A striking feature of this disease is that a range of different mutations in ribosomal proteins results in similar disease phenotypes primarily characterized by erythrocyte abnormalities and macrocytic anemia, while most other cell types in the body are minimally affected. Previously, we analyzed the erythrocyte membrane proteomes of several DBA patients and identified several proteins that are not typically associated with this cell type and that suggested inflammatory mechanisms contribute to the pathogenesis of DBA. In this study, we evaluated the erythrocyte cytosolic proteome of DBA patients through in-depth analysis of hemoglobin-depleted erythrocyte cytosols. Simple, reproducible, hemoglobin depletion using nickel columns enabled in-depth analysis of over 1000 cytosolic erythrocyte proteins with only moderate total analysis time per proteome. Label-free quantitation and statistical analysis identified 29 proteins with significantly altered abundance levels in DBA patients compared to matched healthy control donors. Proteins that were significantly increased in DBA erythrocyte cytoplasms included three proteasome subunit beta proteins that make up the immunoproteasome and proteins induced by interferon-γ such as n-myc interactor and interferon-induced 35 kDa protein [NMI and IFI35 respectively]. Pathway analysis confirmed the presence of an inflammatory signature in erythrocytes of DBA patients and predicted key upstream regulators including mitogen activated kinase 1, interferon-γ, tumor suppressor p53, and tumor necrosis factor. These results show that erythrocytes in DBA patients are intrinsically different from those in healthy controls which may be due to an inflammatory response resulting from the inherent molecular defect of ribosomal protein

  9. In-Depth, Label-Free Analysis of the Erythrocyte Cytoplasmic Proteome in Diamond Blackfan Anemia Identifies a Unique Inflammatory Signature.

    PubMed

    Pesciotta, Esther N; Lam, Ho-Sun; Kossenkov, Andrew; Ge, Jingping; Showe, Louise C; Mason, Philip J; Bessler, Monica; Speicher, David W

    2015-01-01

    Diamond Blackfan Anemia (DBA) is a rare, congenital erythrocyte aplasia that is usually caused by haploinsufficiency of ribosomal proteins due to diverse mutations in one of several ribosomal genes. A striking feature of this disease is that a range of different mutations in ribosomal proteins results in similar disease phenotypes primarily characterized by erythrocyte abnormalities and macrocytic anemia, while most other cell types in the body are minimally affected. Previously, we analyzed the erythrocyte membrane proteomes of several DBA patients and identified several proteins that are not typically associated with this cell type and that suggested inflammatory mechanisms contribute to the pathogenesis of DBA. In this study, we evaluated the erythrocyte cytosolic proteome of DBA patients through in-depth analysis of hemoglobin-depleted erythrocyte cytosols. Simple, reproducible, hemoglobin depletion using nickel columns enabled in-depth analysis of over 1000 cytosolic erythrocyte proteins with only moderate total analysis time per proteome. Label-free quantitation and statistical analysis identified 29 proteins with significantly altered abundance levels in DBA patients compared to matched healthy control donors. Proteins that were significantly increased in DBA erythrocyte cytoplasms included three proteasome subunit beta proteins that make up the immunoproteasome and proteins induced by interferon-γ such as n-myc interactor and interferon-induced 35 kDa protein [NMI and IFI35 respectively]. Pathway analysis confirmed the presence of an inflammatory signature in erythrocytes of DBA patients and predicted key upstream regulators including mitogen activated kinase 1, interferon-γ, tumor suppressor p53, and tumor necrosis factor. These results show that erythrocytes in DBA patients are intrinsically different from those in healthy controls which may be due to an inflammatory response resulting from the inherent molecular defect of ribosomal protein

  10. Conjugated Bilirubin Triggers Anemia by Inducing Erythrocyte Death

    PubMed Central

    Lang, Elisabeth; Gatidis, Sergios; Freise, Noemi F; Bock, Hans; Kubitz, Ralf; Lauermann, Christian; Orth, Hans Martin; Klindt, Caroline; Schuier, Maximilian; Keitel, Verena; Reich, Maria; Liu, Guilai; Schmidt, Sebastian; Xu, Haifeng C; Qadri, Syed M; Herebian, Diran; Pandyra, Aleksandra A; Mayatepek, Ertan; Gulbins, Erich; Lang, Florian; Häussinger, Dieter; Lang, Karl S; Föller, Michael; Lang, Philipp A

    2015-01-01

    Hepatic failure is commonly associated with anemia, which may result from gastrointestinal bleeding, vitamin deficiency, or liver-damaging diseases, such as infection and alcohol intoxication. At least in theory, anemia during hepatic failure may result from accelerated clearance of circulating erythrocytes. Here we show that bile duct ligation (BDL) in mice leads to severe anemia despite increased reticulocyte numbers. Bilirubin stimulated suicidal death of human erythrocytes. Mechanistically, bilirubin triggered rapid Ca2+ influx, sphingomyelinase activation, formation of ceramide, and subsequent translocation of phosphatidylserine to the erythrocyte surface. Consistent with our in vitro and in vivo findings, incubation of erythrocytes in serum from patients with liver disease induced suicidal death of erythrocytes in relation to their plasma bilirubin concentration. Consistently, patients with hyperbilirubinemia had significantly lower erythrocyte and significantly higher reticulocyte counts compared to patients with low bilirubin levels. Conclusion: Bilirubin triggers suicidal erythrocyte death, thus contributing to anemia during liver disease. (Hepatology 2015;61:275–284) PMID:25065608

  11. Bivariate and multivariate analyses of the correlations between stability of the erythrocyte membrane, serum lipids and hematological variables.

    PubMed

    Bernardino Neto, M; de Avelar, E B; Arantes, T S; Jordão, I A; da Costa Huss, J C; de Souza, T M T; de Souza Penha, V A; da Silva, S C; de Souza, P C A; Tavares, M; Penha-Silva, N

    2013-01-01

    The observation that the fluidity must remain within a critical interval, outside which the stability and functionality of the cell tends to decrease, shows that stability, fluidity and function are related and that the measure of erythrocyte stability allows inferences about the fluidity or functionality of these cells. This study determined the biochemical and hematological variables that are directly or indirectly related to erythrocyte stability in a population of 71 volunteers. Data were evaluated by bivariate and multivariate analysis. The erythrocyte stability showed a greater association with hematological variables than the biochemical variables. The RDW stands out for its strong correlation with the stability of erythrocyte membrane, without being heavily influenced by other factors. Regarding the biochemical variables, the erythrocyte stability was more sensitive to LDL-C. Erythrocyte stability was significantly associated with RDW and LDL-C. Thus, the level of LDL-C is a consistent link between stability and functionality, suggesting that a measure of stability could be more one indirect parameter for assessing the risk of degenerative processes associated with high levels of LDL-C.

  12. In vitro effects of quercetin on oxidative stress mediated in human erythrocytes by benzoic acid and citric acid.

    PubMed

    Baş, Hatice; Kalender, Suna; Pandir, Dilek

    2014-01-01

    Benzoic acid (BA) and citric acid (CA) are food additives commonly used in many food products. Food additives play an important role in food supply but they can cause various harmful effects. The in vitro adverse effects of BA and CA and the protective effect of quercetin on human erythrocytes were investigated by measuring malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities. Erythrocytes were incubated with BA and CA, at three doses of 50, 100 and 200 microg/ml, and quercetin, at a concentration of 10 microM. After BA and CA application, a dose-dependent increase in MDA level and decreases in SOD, CAT, GST and GPx activities were found in erythrocytes. Among the two food additives, BA exerted a more harmful influence on human erythrocytes than CA. The protective effects of quercetin against oxidative stress--induction in the human erythrocytes by CA and BA, were found when these two food additives were applied at each of three doses of 50, 100 and 200 microg/ml. However, complete protection of quercetin against CA toxicity was only observed when this agent was applied at a lower dose of 50 microg/ml. Quercetin did not completely protect erythrocytes even at the lowest concentration of BA.

  13. Reversible Sodium Pump Defect and Swelling in the Diabetic Rat Erythrocyte: Effects on Filterability and Implications for Microangiopathy

    NASA Astrophysics Data System (ADS)

    Kowluru, R.; Bitensky, M. W.; Kowluru, A.; Dembo, M.; Keaton, P. A.; Buican, T.

    1989-05-01

    We have found a defect in the ouabain-sensitive Na+,K+-ATPase (Na+ pump, EC 3.6.1.37) of erythrocytes from streptozotocin diabetic rats. This defect was accompanied by an increase in cell volume and osmotic fragility and a decrease in the cytosolic K+/Na+ ratio. There was also a doubling in the time needed for diabetic erythrocytes to pass through 4.7-μ m channels in a polycarbonate filter. Our data are consistent with a primary defect in the erythrocyte Na+ pump and secondary changes in cell volume, osmotic fragility, K+/Na+ ratio, and cell filterability. All were reversed or prevented in vivo by insulin or the aldose reductase inhibitor Sorbinil. Protein kinase C agonists (phorbol ester and diacylglycerol) and agonist precursor (myo-inositol) reversed the Na+ pump lesion, suggesting that protein kinase C-dependent phosphorylation of the 100-kDa subunit regulates Na+ pump activity and that insulin can influence erythrocyte protein kinase C activity. Ouabain inhibition of the erythrocyte Na+ pump also produced increases in cell size and reductions in rates of filtration. Theoretical treatment of the volume changes also predicts reduction in filterability as a consequence of cell swelling. We suggest that enlarged erythrocytes could play a role in the evolution of the microvascular changes of diabetes mellitus.

  14. Comparison between internal microviscosity of low-density erythrocytes and the microviscosity of hemoglobin solutions: an electron paramagnetic resonance study.

    PubMed Central

    Gennaro, A M; Luquita, A; Rasia, M

    1996-01-01

    The hypothesis that the internal viscosity of erythrocytes is governed by the intracellular hemoglobin (Hb) concentration is examined. Here viscosity is determined by labeling of the cytoplasmic reduced glutathione with the spin label maleimido-Tempo. Erythrocyte populations with different Hb concentrations in isosmotic conditions were obtained through incomplete lysis, followed by cell resealing, and discontinuous density gradient separation. This procedure maintains normal cell shape and volume. Microviscosity of membrane-free Hb solutions was measured by addition of spin labeled glutathione. It was found that microviscosity values are similar for the erythrocyte cytoplasm and for Hb solutions of equivalent concentrations, showing that the erythrocyte membrane does not have any influence on internal microviscosity. The dependence of the microviscosity on the concentration of Hb solutions was compared with results of macroscopic viscosity obtained by other authors. It is concluded that microviscosity is sensitive to individual properties of the Hb molecule (intrinsic viscosity), but that it is not sensitive to intermolecular interactions. As the microviscosity behavior as a function of Hb concentration is the same in Hb solutions as in the erythrocyte cytoplasm, the inferences regarding macroscopic viscosity in Hb solutions could be translated to the rheological properties of the erythrocyte cytoplasm. Thus, these properties could be predicted from the values of the mean corpuscular Hb concentration. PMID:8804621

  15. Carbonic anhydrase activity in primary sensory neurons. II. Influence of environmental factors on the phenotypic expression of the enzyme in dissociated cultures of chicken dorsal root ganglion cells.

    PubMed

    Barakat, I; Kazimierczak, J; Droz, B

    1986-01-01

    Neuronal subpopulations of dorsal root ganglion (DRG) cells in the chicken exhibit carbonic anhydrase (CA) activity. To determine whether CA activity is expressed by DRG cells maintained in in vitro cultures, dissociated DRG cells from 10-day-old chick embryos were cultured on a collagen substrate. The influence exerted by environmental factors on the enzyme expression was tested under various conditions of culture. Neuron-enriched cell cultures and mixed DRG-cell cultures (including numerous non-neuronal cells) were performed either in a defined medium or in a horse serum-supplemented medium. In all the tested conditions, subpopulations of cultured sensory neurons expressed CA activity in their cell bodies, while their neurites were rarely stained; in each case, the percentage of CA-positive neurons declined with the age of the cultures. The number and the persistence of neurons possessing CA activity as well as the intensity of the reaction were enhanced by addition of horse serum. In contrast, the expression of the neuronal CA activity was not affected by the presence of non-neuronal cells or by the rise of CO2 concentration. Thus, the appearance and disappearance of neuronal subpopulations expressing CA activity may be decisively influenced by factors contained in the horse serum. The loss of CA-positive neurons with time could result from a cell selection or from genetic repression. Analysis of the time curves does not support a preferential cell death of CA-positive neurons but suggests that the eventual conversion of CA-positive neurons into CA-negative neurons results from a loss of the enzyme activity. These results indicate that the phenotypic expression of cultured sensory neurons is dependent on defined environmental factors.

  16. Action of glycosyl transferases upon "Bombay" (Oh) erythrocytes. Conversion to cells showing blood-group H and A specificities.

    PubMed

    Schenkel-Brunner, H; Prohaska, R; Tuppy, H

    1975-08-15

    Individuals of the rare "Bombay" (Oh) blood-group phenotype lacking, due to a genetic defect, the alpha(1-2)fucosyl transferase, which is responsible for converting blood-group H precursor substances to H-specific structures. Treatment with GDP-fucose and alpha(1-2)fucosyl transferase prepared from gastric mucosa of O individuals to transform native or ficin-treated "Bombay" erythrocytes into cells phenotypically resembling O cells. The transformation was achieved, however, after prior incubation of the "Bombay" erythrocytes with neuraminidase, indicating that blood-group H precursor molecules on the surface of these cells are masked by sialyl residues. Blood-group A specificity was conferred upon neuraminidase-treated "Bombay" cells by enzymatic transfer of alpha-N-acetylgalactosamine residues, in addition to alpha-fucose residues.

  17. Effect of propranolol on normal human erythrocytes.

    PubMed

    Fortier, N L; Snyder, L M; Palek, J; Weiss, E B; Mancini, C; Falcone, J

    1977-01-01

    The present study was undertaken to standardize the effect of propranolol on normal human red cells and thus establish certain parameters enabling us to evaluate propranolol's effect on pathological cells. Normal human erythrocytes lost 40 MEq. of potassium, decreased the intracellular pH by 0.06 units, and shifted the oxyhemoglobin dissociation curve 6.0 mm. Hg to the right in the presence of propranolol. The series of events and magnitude of the response induced by propranolol was time dependent and sensitive to temperature, pH, drug concentration, and erythrocyte concentration. Calcium was an absolute requirement for maximal propranolol action with simultaneous incorporation of trace amounts of radioactive calcium into the cell. Chelation of calcium with EDTA or EGTA inhibited the response to propranolol.

  18. Determinants of Erythrocyte Hydration In Current Opinion in Hematology

    PubMed Central

    Rinehart, Jesse; Gulcicek, Erol E.; Joiner, Clinton H.; Lifton, Richard P.; Gallagher, Patrick G.

    2012-01-01

    Purpose of Review Maintenance of cellular water and solute homeostasis is critical for survival of the erythrocyte. Inherited or acquired disorders that perturb this homeostasis jeopardize the erythrocyte, leading to its premature destruction. This report reviews recent progress in our understanding the determinants of erythrocyte hydration and its related disorders. Recent Findings The molecular and genetic bases of primary disorders of erythrocyte hydration are poorly understood. Recent studies have implicated roles for the anion transporter, SLC4A1, and the Rh-associated glycoprotein, RhAG. The most common secondary disorder associated with perturbed hydration of the erythrocyte is sickle cell disease, where dehydration contributes to disease pathology and clinical complications. Advances in understanding the mechanisms regulating erythrocyte solute and water content, particularly associated with KCl cotransport and Gardos channel activation, have revealed novel signaling mechanisms controlling erythrocyte hydration. These signaling pathways may provide innovative strategies to prevent erythrocyte dehydration in sickle cell disease. Summary Clinical, translational and biologic studies all contribute to our knowledge of erythrocyte hydration. Understanding the mechanisms controlling erythrocyte water and solute homeostasis will serve as a paradigm for other cells and may reveal new therapeutic targets for disease prevention and treatment. PMID:20182354

  19. Phase separation in frozen erythrocyte membrane preparations.

    PubMed

    Finean, J B; Hutchinson, A; Mills, D

    1985-10-01

    The reversible formation of a lipid-like phase in frozen preparations of erythrocyte membranes has been studied by X-ray diffraction and by electron microscopy of freeze-fracture replicas. The observations provide strong evidence for lateral migration or displacement at specific temperatures of intra-membrane particles. This creates large areas of particle-free membranes which fracture preferentially so as to dominate the freeze-fracture image.

  20. Erythrocyte membrane elasticity during in vivo ageing.

    PubMed

    Nash, G B; Wyard, S J

    1981-05-01

    Changes in the ability of senescent erythrocytes to pass through the microcirculation may cause them to be trapped in the spleen and removed from the blood. To help understand this process we have measured erythrocyte membrane elasticity, to see whether it changes during in vivo ageing. Human and rabbit red cells were fractionated by isopycnic sedimentation to obtain samples of aged and young cells. These were subjected to micropipette analysis in order to determine their membrane shear elastic modulus. We found that the membrane rigidity did not significantly alter as red cells aged. Previously we have also demonstrated that the changed size and shape of aged cells is unlikely to explain their removal from the circulation (Nash, G.B. and Wyard, S.J. (1981) Biorheology, in the press). Thus we conclude that the lifespan of erythrocytes is not determined by factors related to membrane flexibility or cell shape but may depend on changes in their viscous properties (as suggested by Williams, A.R. and Morris, D.R. (1980), Scand. J. Haematol. 24, 57--62).

  1. Erythrocyte shape simulation by numerical optimization.

    PubMed

    Grebe, R; Zuckermann, M J

    1990-01-01

    In a recent paper we examined the morphology of erythrocytes in terms of the mean mean curvature (MMC) of their cell membranes. A computer simulation of these shapes based on the different geometries showed that the MMC increased from the sphero-stomatocyte to the spheroechinocyte via the discocyte. In this work we extend this analysis by using a numerical optimization method based on importance sampling and the principle of adiabatic cooling. The erythrocyte membrane is treated as a single closed fluid lamina exhibiting viscoelastic characteristics. The energy function of the lamina includes the following terms: (i) Curvature-elastic energy terms which depend on both local and global curvature. (ii) A term describing the compression elasticity of the lamina. (iii) A term which depends on the volume of the cell and which is related to the osmotic pressure across the membrane. In the simulation the cell is assumed to have axial symmetry and it can therefore be described by a finite set of conic sections. So far we have been able to obtain an energy minimum corresponding to a discocyte shape using a sphere as the initial configuration. Our results therefore imply that the well-known sequence of erythrocyte shapes could solely be governed by the above mentioned properties of an ideal fluid forming a closed singly connected lamina.

  2. Platelet and not erythrocyte microparticles are procoagulant in transfused thalassaemia major patients.

    PubMed

    Agouti, Imane; Cointe, Sylvie; Robert, Stéphane; Judicone, Coralie; Loundou, Anderson; Driss, Fathi; Brisson, Alain; Steschenko, Dominique; Rose, Christian; Pondarré, Corinne; Bernit, Emmanuelle; Badens, Catherine; Dignat-George, Françoise; Lacroix, Romaric; Thuret, Isabelle

    2015-11-01

    The level of circulating platelet-, erythrocyte-, leucocyte- and endothelial-derived microparticles detected by high-sensitivity flow cytometry was investigated in 37 β-thalassaemia major patients receiving a regular transfusion regimen. The phospholipid procoagulant potential of the circulating microparticles and the microparticle-dependent tissue factor activity were evaluated. A high level of circulating erythrocyte- and platelet-microparticles was found. In contrast, the number of endothelial microparticles was within the normal range. Platelet microparticles were significantly higher in splenectomized than in non-splenectomized patients, independent of platelet count (P < 0·001). Multivariate analysis indicated that phospholipid-dependent procoagulant activity was influenced by both splenectomy (P = 0·001) and platelet microparticle level (P < 0·001). Erythrocyte microparticles were not related to splenectomy, appear to be devoid of proper procoagulant activity and no relationship between their production and haemolysis, dyserythropoiesis or oxidative stress markers could be established. Intra-microparticle labelling with anti-HbF antibodies showed that they originate only partially (median of 28%) from thalassaemic erythropoiesis. In conclusion, when β-thalassaemia major patients are intensively transfused, the procoagulant activity associated with thalassaemic erythrocyte microparticles is probably diluted by transfusions. In contrast, platelet microparticles, being both more elevated and more procoagulant, especially after splenectomy, may contribute to the residual thrombotic risk reported in splenectomized multi-transfused β-thalassaemia major patients.

  3. Viscoelasticity of packed erythrocyte suspensions subjected to low amplitude oscillatory deformation.

    PubMed

    Drasler, W J; Smith, C M; Keller, K H

    1987-09-01

    Concentrated adult erythrocyte suspensions were subjected to low amplitude oscillatory shear in a Weissenberg rheogoniometer equipped with a cone-and-plate assembly. The dynamic viscoelastic properties of the suspension were measured over a broad range of frequency by a numerical solution that accounted for fluid inertia. Variation of shear amplitude and cell volume percent, and comparison of buffered saline, plasma, and dextran as suspending media showed that the cellular elements had undergone small bending and shearing deformations. Studies of normal adult erythrocytes, hypotonically swollen cells, temperature-altered cells, and erythrocyte ghosts suggested that the method was evaluating membrane material properties. The normal membrane was found to exhibit a shear rate dependent elastic modulus that increased by more than a factor of 20 over a frequency range from 0.0076 Hz to 60 Hz. The membrane viscosity showed a substantial drop with frequency indicative of a frequency thinning phenomenon. At high frequency of deformation the viscous response of normal erythrocytes was no longer indicative of a membrane property due to the dominant influence of the internal hemoglobin solution. The studies generally supported the ability of the method to quantify relative membrane material properties and detect changes in membrane structure.

  4. Chronic cigarette smoking alters erythrocyte membrane lipid composition and properties in male human volunteers.

    PubMed

    Padmavathi, Pannuru; Reddy, Vaddi Damodara; Kavitha, Godugu; Paramahamsa, Maturu; Varadacharyulu, Nallanchakravarthula

    2010-11-01

    Cigarette smoking is a major lifestyle factor influencing the health of human beings. The present study investigates smoking induced alterations on the erythrocyte membrane lipid composition, fluidity and the role of nitric oxide. Thirty experimental and control subjects (age 35+/-8) were selected for the study. Experimental subjects smoke 12+/-2 cigarettes per day for 7-10 years. In smokers elevated nitrite/nitrate levels in plasma and red cell lysates were observed. Smokers showed increased hemolysis, erythrocyte membrane lipid peroxidation, protein carbonyls, C/P ratio (cholesterol and phospholipid ratio), anisotropic (gamma) value with decreased Na(+)/K(+)-ATPase activity and sulfhydryl groups. Alterations in smokers erythrocyte membrane individual phospholipids were also evident from the study. Red cell lysate nitric oxide positively correlated with C/P ratio (r=0.565) and fluorescent anisotropic (gamma) value (r=0.386) in smokers. Smoking induced generation of reactive oxygen/nitrogen species might have altered erythrocyte membrane physico-chemical properties.

  5. Viscoelasticity of packed erythrocyte suspensions subjected to low amplitude oscillatory deformation.

    PubMed Central

    Drasler, W J; Smith, C M; Keller, K H

    1987-01-01

    Concentrated adult erythrocyte suspensions were subjected to low amplitude oscillatory shear in a Weissenberg rheogoniometer equipped with a cone-and-plate assembly. The dynamic viscoelastic properties of the suspension were measured over a broad range of frequency by a numerical solution that accounted for fluid inertia. Variation of shear amplitude and cell volume percent, and comparison of buffered saline, plasma, and dextran as suspending media showed that the cellular elements had undergone small bending and shearing deformations. Studies of normal adult erythrocytes, hypotonically swollen cells, temperature-altered cells, and erythrocyte ghosts suggested that the method was evaluating membrane material properties. The normal membrane was found to exhibit a shear rate dependent elastic modulus that increased by more than a factor of 20 over a frequency range from 0.0076 Hz to 60 Hz. The membrane viscosity showed a substantial drop with frequency indicative of a frequency thinning phenomenon. At high frequency of deformation the viscous response of normal erythrocytes was no longer indicative of a membrane property due to the dominant influence of the internal hemoglobin solution. The studies generally supported the ability of the method to quantify relative membrane material properties and detect changes in membrane structure. PMID:3651555

  6. Measurement of the T cell response to pre-erythrocytic vaccination in mice

    PubMed Central

    Guthmiller, Jenna J.; Zander, Ryan A.; Butler, Noah S.

    2016-01-01

    Whole attenuated parasite vaccines designed to elicit immunity against the clinically silent pre-erythrocytic stage of Plasmodium infection represent the most efficacious experimental platforms currently in clinical trial. Studies in rodents and humans show that T cells mediate vaccine-induced protection. Thus, determining the quantitative and qualitative properties of these T cells remains a major research focus. Most rodent models of pre-erythrocytic anti-Plasmodium vaccination focus on circumsporozoite-specific CD8 T cell responses in BALB/c mice. However, CD4 T cells and non-circumsporozoite-specific CD8 T cells also significantly contribute to protection. Here we describe alternative approaches that enable detection and functional characterization of total CD8 and CD4 T cell responses induced by pre-erythrocytic vaccination in mice. These flow cytometry-based approaches rely on monitoring the modulation of expressed integrins and co-receptors on the surface of T cells in vaccinated mice. The approaches enable direct determination of the magnitude, kinetics, distribution, phenotype, and functional features of T cell responses induced by infection or whole-parasite vaccination using any mouse-parasite species combination. PMID:26450376

  7. Spectral Markers of Erythrocytes on Solid Substrate

    NASA Astrophysics Data System (ADS)

    Paiziev, Adkhamjon A.; Krakhmalev, V. A.

    Proposed in previous paper [1,2] the new nondestructive method of optical microscopy allows to examine the structures of living cells (human erythrocytes) in their natural colors without its staining by using a specially designed substrate for deposition of biological sample and observing a native blood smears in reflected light. Color interference contrast image is achieved due to special condition of experiment is connected with chose of angle of incidental light, wave length of light of reflected ray, chemical composition of sample, thickness of sample, refractive index of sample, refractive index of substrate, chemical composition of substrate [1,2]. We can identify chemical compounds of erythrocytes after calibration color scale by alternative methods. For comparison we used Synchrotron Radiation based Fourier Transformed Infrared (SR-FTIR) microspectroscopy. By focusing of infrared beam of FTIR microscope on cell surface we can screen and distinguish difference erythrocytes by its color. For example on Fig. 49.1 we can see two neighbored erythrocytes where one of them have red color (point 1) and other-green (point 5). To identify their spectral markers we measured IR absorption spectra of cells at different points (1,2,3,4 and 5). Intermediated area (points 3 and 4) correspond to substrate spectra (silicon substrate) and their spectra are same. The peaks at 2,850 and 2,920 cm-1 correspond mainly to the CH2 stretching modes of the methylene chains in membrane lipids. At 1,650 cm-1 the amide I band is observed, which results, principally, from the n(CO) stretching vibrations of the protein amide bonds; the amide II band, near 1,550 cm-1, is a combination of the d(N-H) bending and n(C-N) stretching vibrations of the amide bonds. The peaks at 2,850 and 2,920 cm-1 correspond mainly to the CH2 stretching modes of the methylene chains in membrane lipids [3. The intensities of the absorption bands at 2,920 and 2,850 cm-1 in green erythrocyte (point 5) were also

  8. Further studies on osmotic resistance of nucleated erythrocytes: observations with pigeon, peafowl, lizard and toad erythrocytes during changes in temperature and pH.

    PubMed

    Oyewale, J O

    1994-02-01

    The osmotic resistance of pigeon, peafowl, lizard and toad erythrocytes at different temperatures and pH was studied. Erythrocytes from female pigeons showed greater osmotic resistance than those from males, but no sex difference appeared with erythrocytes from peafowls. Pigeon erythrocytes were more resistant and the red blood cell, packed cell volume and haemoglobin values were higher than those in peafowls. Although no significant differences appeared in their haematological values, erythrocytes from the lizard were more resistant than erythrocytes from the toad. At higher temperature, the osmotic resistance of pigeon, lizard and toad erythrocytes increased, while that of peafowl erythrocytes decreased. The resistance of toad erythrocytes decreased in acidic and alkaline solutions, but that of peafowl erythrocytes increased in both solutions. However, with pigeon and lizard erythrocytes, the resistance was unaltered in alkaline solution and decreased in acidic solution.

  9. Further studies on osmotic resistance of nucleated erythrocytes: observations with pigeon, peafowl, lizard and toad erythrocytes during changes in temperature and pH.

    PubMed

    Oyewale, J O

    1994-02-01

    The osmotic resistance of pigeon, peafowl, lizard and toad erythrocytes at different temperatures and pH was studied. Erythrocytes from female pigeons showed greater osmotic resistance than those from males, but no sex difference appeared with erythrocytes from peafowls. Pigeon erythrocytes were more resistant and the red blood cell, packed cell volume and haemoglobin values were higher than those in peafowls. Although no significant differences appeared in their haematological values, erythrocytes from the lizard were more resistant than erythrocytes from the toad. At higher temperature, the osmotic resistance of pigeon, lizard and toad erythrocytes increased, while that of peafowl erythrocytes decreased. The resistance of toad erythrocytes decreased in acidic and alkaline solutions, but that of peafowl erythrocytes increased in both solutions. However, with pigeon and lizard erythrocytes, the resistance was unaltered in alkaline solution and decreased in acidic solution. PMID:8085400

  10. Identification of the Molecular and Genetic Basis of PX2, a Glycosphingolipid Blood Group Antigen Lacking on Globoside-deficient Erythrocytes*

    PubMed Central

    Westman, Julia S.; Benktander, John; Storry, Jill R.; Peyrard, Thierry; Hult, Annika K.; Hellberg, Åsa; Teneberg, Susann; Olsson, Martin L.

    2015-01-01

    The x2 glycosphingolipid is expressed on erythrocytes from individuals of all common blood group phenotypes and elevated on cells of the rare P/P1/Pk-negative p blood group phenotype. Globoside or P antigen is synthesized by UDP-N-acetylgalactosamine:globotriaosyl-ceramide 3-β-N-acetylgalactosaminyltransferase encoded by B3GALNT1. It is the most abundant non-acid glycosphingolipid on erythrocytes and displays the same terminal disaccharide, GalNAcβ3Gal, as x2. We encountered a patient with mutations in B3GALNT1 causing the rare P-deficient P1k phenotype and whose pretransfusion plasma was unexpectedly incompatible with p erythrocytes. The same phenomenon was also noted in seven other unrelated P-deficient individuals. Thin-layer chromatography, mass spectrometry, and flow cytometry were used to show that the naturally occurring antibodies made by p individuals recognize x2 and sialylated forms of x2, whereas x2 is lacking on P-deficient erythrocytes. Overexpression of B3GALNT1 resulted in synthesis of both P and x2. Knockdown experiments with siRNA against B3GALNT1 diminished x2 levels. We conclude that x2 fulfills blood group criteria and is synthesized by UDP-N-acetylgalactosamine: globotriaosylceramide 3-β-N-acetylgalactosaminyltransferase. Based on this linkage, we proposed that x2 joins P in the GLOB blood group system (ISBT 028) and is renamed PX2 (GLOB2). Thus, in the absence of a functional P synthase, neither P nor PX2 are formed. As a consequence, naturally occurring anti-P and anti-PX2 can be made. Until the clinical significance of anti-PX2 is known, we also recommend that rare P1k or P2k erythrocyte units are preferentially selected for transfusion to Pk patients because p erythrocytes may pose a risk for hemolytic transfusion reactions due to their elevated PX2 levels. PMID:26055721

  11. Uric acid protects erythrocytes from ozone-induced changes

    SciTech Connect

    Meadows, J.; Smith, R.C.

    1987-08-01

    Uric acid effectively reduced hemolysis and methemoglobin formation in bovine and swine erythrocytes bubbled with ozone in vitro. In bovine erythrocytes, formation of thiobarbituric acid-reactive material was inhibited by uric acid, but there was little immediate protection for the swine cells. Antioxidant protection was due to preferential degradation of the uric acid by ozone. These results provide evidence to support the hypothesis that in plasma, uric acid can provide antioxidant protection for erythrocytes.

  12. Hepatic or splenic targeting of carrier erythrocytes: a murine model

    SciTech Connect

    Zocchi, E.; Guida, L.; Benatti, U.; Canepa, M.; Borgiani, L.; Zanin, T.; De Flora, A.

    1987-10-01

    Carrier mouse erythrocytes, i.e., red cells, subjected to a dialysis technique involving transient hypotonic hemolysis and isotonic resealing were treated in vitro in three different ways: (a) energy depletion by exposure for 90 min at 42 degrees C; (b) desialylation by incubation with neuroaminidase; and (c) oxidative stress by incubation with H/sub 2/O/sub 2/ and NaN3. Procedure (c) afforded maximal damage, as shown by analysis of biochemical properties of the treated erythrocytes. Reinfusion in mice of the variously manipulated erythrocytes following their /sup 51/Cr labeling showed extensive fragilization as indicated by rapid clearance of radioactivity from the circulation. Moreover, both the energy-depleted and the neuraminidase-treated erythrocytes showed a preferential liver uptake, reaching 50 and 75%, respectively, within 2 h. On the other hand, exposure of erythrocytes to the oxidant stress triggered a largely splenic removal, accounting for almost 40% of the reinjected cells within 4 h. Transmission electron microscopy of liver from mice receiving energy-depleted erythrocytes demonstrated remarkable erythrocyte congestion within the sinusoids, followed by hyperactivity of Kupffer cells and by subsequent thickening of the perisinusoidal Disse space. Concomitantly, levels of serum transaminase activities were moderately increased. Each of the three procedures of manipulation of carrier erythrocytes may prove applicable under conditions where selective targeting of erythrocyte-encapsulated chemicals and drugs to either the liver or the spleen has to be achieved.

  13. Accumulation of Paprika Carotenoids in Human Plasma and Erythrocytes.

    PubMed

    Nishino, Azusa; Ichihara, Takashi; Takaha, Takeshi; Kuriki, Takashi; Nihei, Hideko; Kawamoto, Kazuhisa; Yasui, Hiroyuki; Maoka, Takashi

    2015-01-01

    The accumulation (incorporation) of paprika carotenoid in human plasma and erythrocytes was investigated. A paprika carotenoid supplement (14 mg/day) was ingested for 4 weeks by 5 young healthy volunteers (3 men and 2 women). After 2 weeks of carotenoid ingestion, the carotenoid levels in plasma and erythrocytes increased by 1.2-fold and 2.2-fold, respectively. Characteristic carotenoids found in paprika (capsanthin, cucurbitaxanthin A, and cryptocapsin) were detected in both plasma and erythrocytes. An oxidative metabolite of capsanthin (capsanthone) was also found in both plasma and erythrocytes.

  14. The influence of carbon sources on recombinant-human- growth-hormone production by Pichia pastoris is dependent on phenotype: a comparison of Muts and Mut+ strains.

    PubMed

    Orman, Mehmet Ali; Calik, Pinar; Ozdamar, Tunçer H

    2009-03-01

    The influence of carbon sources on rhGH (recombinant human growth hormone) production by two Pichia pastoris strains having different methanol utilization phenotypes (P. pastoris-hGH-Mut(+) and P. pastoris-hGH-Mut(s)) was investigated using batch bioreactors. The effect of methanol concentration (C(MeOH)) in defined and complex media, and further glycerol/methanol mixed defined media, was analysed systematically over a wide range. With methanol as the sole carbon source, strain Mut(s) grew only slightly, whereas with Mut(+), a cell concentration (C(X)) of 6.0 g of dry cells/dm(3) was obtained and an rhGH concentration (C(rhGH)) of 0.032 g/dm(3) was produced. In complex medium without glycerol at a C(MeOH) of 2% (v/v), a C(rhGH) of 0.16 g of rhGH/dm(3) was produced by Mut(s), a value 3-fold higher than that produced by Mut(+), despite the fact that the C(X) of Mut(+) (6.1 g/dm(3)) was 2-fold higher than that of Mut(s) (3.0 g/dm(3)). In a glycerol/methanol mixed defined medium, methanol consumption began when glycerol was totally depleted, indicating that glycerol is a repressor of the AOX1 (alcohol oxidase-1 gene) promoter. With strain Mut(s) at a glycerol concentration (C(Gly)) of 30 g/dm(3) and a C(MeOH) of 1% (v/v), the C(rhGH) produced was 0.11 g/dm(3), whereas, with the Mut(+) strain, a C(rhGH) of 0.06 g/dm(3) was obtained at a C(Gly) of 30 g/dm(3) and a C(MeOH) of 4%. As methanol is not consumed by Mut(s) strain effectively and the presence of methanol in the fermentation broth triggers induction of the AOX1 promoter, our results encourage the use of the Mut(s) strain for rhGH production. In addition to rhGH production, the specific cell growth rates, specific methanol and/or glycerol utilization rates and maintenance coefficients in methanol- and glycerol-based defined media were determined. With a methanol-based defined medium and using the Mut(+) strain, a higher specific growth rate (mu) of approx. 0.14 h(-1) was observed during the exponential cell growth

  15. Erythrocyte membrane tropomyosin. Purification and properties.

    PubMed

    Fowler, V M; Bennett, V

    1984-05-10

    Two polypeptides of Mr approximately 29,000 and 27,000 have been identified in human erythrocyte membranes that cross-react specifically with affinity purified antibodies to chicken gizzard tropomyosin. The cross-reacting polypeptides are quantitatively retained on the membrane after cell lysis if millimolar concentrations of magnesium are included in the lysis and wash buffers, indicating that they are membrane-bound proteins under physiological conditions. Milligram quantities of these immunoreactive polypeptides have been purified to greater than 95% purity from a low salt extract of membranes by DEAE-chromatography, precipitation at pH 4.4, and heating to 85 degrees C to denature contaminants. Physical similarities of the erythrocyte protein to other tropomyosins include (a) amino acid composition (b) anomalous migration of the Mr approximately 29,000 and 27,000 polypeptides on sodium dodecyl sulfate-gels in the presence of 6 M urea to apparent Mr approximately 43,000 and 38,000, respectively (c) arrangement of chains as dimers of Mr approximately 60,000 based on cross-linking studies and calculation of molecular weight from hydrodynamic values (Rs = 5.9 nm, sedimentation coefficient = 2.5 S; partial specific volume = 0.72 cm3/g) and (d) highly asymmetric shape, based on a frictional ratio of 2.07. Binding of erythrocyte tropomyosin to muscle F-actin saturates at one tropomyosin molecule (Mr approximately 60,000) to 6-7 actin monomers and is highly cooperative with a Hill coefficient of about 2.8, similar to muscle tropomyosins. Binding also exhibits a high degree of cooperativity as a function of the magnesium concentration with a transition between no binding and complete binding between 1 and 2 mM MgCl2. Increasing the magnesium concentration from 2 to 10 mM increases the apparent affinity of tropomyosin for actin from approximately 2.6 X 10(6) M-1 to approximately 2.7 X 10(7) M-1 without effect on the Hill coefficient. The tropomyosin polypeptides comprise

  16. Erythrocytic vacuolar rafts induced by malaria parasites.

    PubMed

    Haldar, K; Samuel, B U; Mohandas, N; Harrison, T; Hiller, N L

    2001-03-01

    Studies in the past year displaced long-standing dogmas and provided many new molecular insights into how proteins and solutes move between the erythrocyte plasma membrane and the malarial vacuole. Highlights include a demonstration that (1) detergent-resistant membrane (DRM) rafts exist in the red cell membrane and their resident proteins are detected as rafts in the plasmodial vacuole, (2) a voltage-gated channel in the infected red cell membrane mediates uptake of extracellular nutrient solutes, and (3) intraerythrocytic membranes transport a parasite-encoded adherence antigen to the red cell surface.

  17. Plasmodium falciparum erythrocyte membrane protein 1 is a parasitized erythrocyte receptor for adherence to CD36, thrombospondin, and intercellular adhesion molecule 1.

    PubMed Central

    Baruch, D I; Gormely, J A; Ma, C; Howard, R J; Pasloske, B L

    1996-01-01

    Adherence of mature Plasmodium falciparum parasitized erythrocytes (PRBCs) to microvascular endothelium contributes directly to acute malaria pathology. We affinity purified molecules from detergent extracts of surface-radioiodinated PRBCs using several endothelial cell receptors known to support PRBC adherence, including CD36, thrombospondin (TSP), and intercellular adhesion molecule 1 (ICAM-1). All three host receptors affinity purified P. falciparum erythrocyte membrane protein 1 (PfEMP1), a very large malarial protein expressed on the surface of adherent PRBCs. Binding of PfEMP1 to particular host cell receptors correlated with the binding phenotype of the PRBCs from which PfEMP1 was extracted. Preadsorption of PRBC extracts with anti-PfEMP1 antibodies, CD36, or TSP markedly reduced PfEMP1 binding to CD36 or TSP. Mild trypsinization of intact PRBCs of P. falciparum strains shown to express antigenically different PfEMP1 released different (125)I-labeled tryptic fragments of PfEMP1 that bound specifically to CD36 and TSP. In clone C5 and strain MC, these activities resided on different tryptic fragments, but a single tryptic fragment from clone ItG-ICAM bound to both CD36 and TSP. Hence, the CD36- and TSP-binding domains are distinct entities located on a single PfEMP1 molecule. PfEMP1, the malarial variant antigen on infected erythrocytes, is therefore a receptor for CD36, TSP, and ICAM-1. A therapeutic approach to block or reverse adherence of PRBCs to host cell receptors can now be pursued with the identification of PfEMP1 as a malarial receptor for PRBC adherence to host proteins. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8622965

  18. Metabolic properties of low ATP erythrocytes of the monotremes.

    PubMed

    Kim, H D; Zeidler, R B; Sallis, J; Nicol, S; Isaacks, R E

    1984-02-13

    The erythrocytes of the monotremes, having a trace amount of ATP, can metabolize glucose to lactate at a rate comparable to human and other mammalian erythrocytes. The echidna energy metabolism is unique in that adenosine can stimulate glycolytic carbon flow, resulting in a nearly 20-fold net synthesis of ATP.

  19. ERYTHROCYTE SENSITIZATION BY BLOOD GROUP-SPECIFIC BACTERIAL ANTIGENS.

    PubMed

    SPRINGER, G F; HORTON, R E

    1964-07-01

    Human and chicken erythrocytes are readily coated in vitro by blood group active protein-lipopolysaccharides and lipopolysaccharides from E. coli O(86) and E. coli O(128). Serum albumin, alpha(2)- and beta-lipoproteins inhibit this sensitization. Blood group B specific agglutination of erythrocytes with B or B-like antigens was obtained with antibodies purified by adsorption on and elution from B erythrocytes. Anti-blood group B and E. coli O(86)-specific antibodies could be eluted from E. coli O(86)-coated O erythrocytes. Eel anti-H(O) serum agglutinated O erythrocytes and only those A(1)B red cells which were coated with blood group H(O) active E. coli products. Blood group active substances specifically inhibited agglutination of lipopolysaccharide-coated erythrocytes by anti-B and anti-H(O) agglutinins. Demonstrable amounts of lipopolysaccharide could only be removed from coated erythrocytes by washing them at elevated temperatures (58 degrees C) in physiological solutions. Red cell sensitization with B active E. coli O(86) substances was achieved in vivo in a minority of severely diseased infants and in germ-free and ordinary chicks which were in tourniquet shock after treatment with cathartics. Therefore, a possible mode by which erythrocytes of patients with severe intestinal disorders acquire antigens is the fixation of bacterial substances to their surfaces, if there are not enough of the normally interfering plasma factors present.

  20. Comparative erythrocyte metabolism in marsupials and monotremes.

    PubMed

    Parkinson, A L; Whittington, A T; Spencer, P B; Grigg, G; Hinds, L; Gallagher, C; Kuchel, P; Agar, N S

    1995-03-01

    Concentrations of ATP and DPG, activities of 10 enzymes and the glycolytic rates were measured in the erythrocytes of 11 species of marsupials and two species of monotremes. Mean DPG concentrations were greater in the erythrocytes of marsupials than those of eutherian mammals. The opposite is true of ATP. Significant findings from the results of enzyme activities were: high activity of hexokinase (7.39 +/- 0.82 EU/g Hb) in the short-beaked echidna, pyruvate kinase (37.49 +/- 1.0 EU/g) Hb in bridled nailtail wallaby and glucose-6-phosphate dehydrogenase (G6PD; 41.66 +/- 1.24 EU/g Hb) in black-striped wallaby. About 6- to 7-fold difference in the activity of G6PD levels between the two species of wombats was confirmed. Glucose phosphate isomerase activity was also shown to be twice as high in the red cells of the common wombat compared with those of the southern hairy nosed wombat. There were wide variations in the glycolytic rate among the species examined.

  1. Histamine increases sickle erythrocyte adherence to endothelium.

    PubMed

    Wagner, Matthew C; Eckman, James R; Wick, Timothy M

    2006-02-01

    Complications of sickle cell anaemia include vascular occlusion triggered by the adherence of sickle erythrocytes to endothelium in the postcapillary venules. Adherence can be promoted by inflammatory mediators that induce endothelial cell adhesion molecule expression and arrest flowing erythrocytes. The present study characterised the effect of histamine stimulation on the kinetics of sickle cell adherence to large vessel and microvascular endothelium under physiological flow. Increased sickle cell adherence was observed within minutes of endothelial activation by histamine and reached a maximum value within 30 min. At steady state, sickle cell adherence to histamine-stimulated endothelium was 47 +/- 4 adherent cells/mm(2), 2.6-fold higher than sickle cell adherence to unstimulated endothelial cells. Histamine-induced sickle cell adherence occurred rapidly and transiently. Studies using histamine receptor agonists and antagonists suggest that histamine-induced sickle cell adhesion depends on simultaneous stimulation of the H(2) and H(4) histamine receptors and endothelial P-selectin expression. These data show that histamine release may promote sickle cell adherence and vaso-occlusion. In vivo histamine release should be studied to determine its role in sickle complications and whether blocking of specific histamine receptors may prevent clinical complications or adverse effects from histamine release stimulated by opiate analgesic treatment.

  2. Binding characteristics of swine erythrocyte insulin receptors

    SciTech Connect

    Dieberg, G.; Bryan, G.S.; Sartin, J.L.; Williams, J.C.; Prince, T.J.; Kemppainen, R.J.

    1985-09-01

    Crossbred gilts had 8.8 +/- 1.1% maximum binding of ( SVI)insulin to insulin receptors on erythrocytes. The number of insulin-binding sites per cell was 137 +/- 19, with a binding affinity ranging from 7.4 X 10(7)M-1 to 11.2 X 10(7)M-1 and mean of 8.8 X 10(7)M-1. Pregnant sows had a significant increase in maximum binding due to an increase in number of receptor sites per cell. Lactating sows fed a high-fiber diet and a low-fiber diet did not develop a significant difference in maximum binding of insulin. Sows fed the low-fiber diet had a significantly higher number of binding sites and a significantly lower binding affinity than did sows fed a high-fiber diet. Receptor-binding affinity was lower in the low-fiber diet group than in cycling gilts, whereas data from sows fed the high-fiber diet did not differ from data for cycling gilts. Data from this study indicated that insulin receptors of swine erythrocytes have binding characteristics similar to those in other species. Pregnancy and diet will alter insulin receptor binding in swine.

  3. Comparative erythrocyte metabolism in marsupials and monotremes.

    PubMed

    Parkinson, A L; Whittington, A T; Spencer, P B; Grigg, G; Hinds, L; Gallagher, C; Kuchel, P; Agar, N S

    1995-03-01

    Concentrations of ATP and DPG, activities of 10 enzymes and the glycolytic rates were measured in the erythrocytes of 11 species of marsupials and two species of monotremes. Mean DPG concentrations were greater in the erythrocytes of marsupials than those of eutherian mammals. The opposite is true of ATP. Significant findings from the results of enzyme activities were: high activity of hexokinase (7.39 +/- 0.82 EU/g Hb) in the short-beaked echidna, pyruvate kinase (37.49 +/- 1.0 EU/g) Hb in bridled nailtail wallaby and glucose-6-phosphate dehydrogenase (G6PD; 41.66 +/- 1.24 EU/g Hb) in black-striped wallaby. About 6- to 7-fold difference in the activity of G6PD levels between the two species of wombats was confirmed. Glucose phosphate isomerase activity was also shown to be twice as high in the red cells of the common wombat compared with those of the southern hairy nosed wombat. There were wide variations in the glycolytic rate among the species examined. PMID:7599974

  4. Migraine and erythrocyte biology: a review.

    PubMed

    Lippi, G; Cervellin, G; Mattiuzzi, C

    2014-12-01

    Migraine is a common disabling headache disorder that is conventionally classified according to the presence or absence of aura. The pathogenesis of this disorder entails a complex interplay of neurovascular factors, that trigger reduction of cerebral blood flow followed by reactive vasodilatation. Despite major emphasis has been placed on the investigation of putative biomarkers that could predict response to specific treatments and prophylaxis, less focus has been directed at the association between migraine and erythrocytosis. Erythrocytosis is typically accompanied by hyperviscosity, that is now considered a crucial determinant in the pathogenesis of migraine. The results of some epidemiological investigations are in substantial agreement to confirm the existence of a significant relationship between increased haemoglobin levels and migraine, whereas some case reports have also reported an effective improvement of symptoms after reduction of erythrocyte count by therapeutic venesection. Interesting evidence has recently emerged from the assessment of red blood cell distribution width (RDW), a simple and inexpensive measure of anysocytosis that has been also associated with a variety of ischaemic and thrombotic disorders other than migraine. The aim of this review was to provide an overview of the current clinical and epidemiological evidence linking migraine and erythrocyte biology.

  5. Dielectric Properties and Ion Mobility in Erythrocytes

    PubMed Central

    Pauly, H.; Schwan, H. P.

    1966-01-01

    The impedance of erythrocytes of man, cattle, sheep, dog, cat, rabbit, and chicken was measured in the range from 0.5 to 250 Mc. The dielectric constant of the red cell interior is 50 at 250 Mc, varies but little with species, and can readily be accounted for by the cells' hemoglobin content. The electrical conductivity of the red cell interior was determined between 70 and 100 Mc. The values differ from species to species within the rather limited range from 4.4 to 5.3 mmho/cm. Removal of the cell membranes does not affect the conductivity. Hence, the cell interior behaves, from an electrical point of view, like a highly concentrated hemoglobin solution. A theoretical value for the electrical conductivity of erythrocyte interiors, which is calculated on the basis of the salt content of the cell, ion mobility, and the volume concentration of the hemoglobin, is roughly twice as large as the measured value. This discrepancy is typical not only of the red blood cell. Pertinent measurements show that it is probably caused by hydrodynamic and possibly by electrostatic effects also, which lower the mobility of the ions. From the lower electrical mobility it appears that a lowered diffusion constant of the electrolytes and nonelectrolytes within the cell is indicated. PMID:5970566

  6. Plasmodium falciparum Secretome in Erythrocyte and Beyond

    PubMed Central

    Soni, Rani; Sharma, Drista; Bhatt, Tarun K.

    2016-01-01

    Plasmodium falciparum is the causative agent of deadly malaria disease. It is an intracellular eukaryote and completes its multi-stage life cycle spanning the two hosts viz, mosquito and human. In order to habituate within host environment, parasite conform several strategies to evade host immune responses such as surface antigen polymorphism or modulation of host immune system and it is mediated by secretion of proteins from parasite to the host erythrocyte and beyond, collectively known as, malaria secretome. In this review, we will discuss about the deployment of parasitic secretory protein in mechanism implicated for immune evasion, protein trafficking, providing virulence, changing permeability and cyto-adherence of infected erythrocyte. We will be covering the possibilities of developing malaria secretome as a drug/vaccine target. This gathered information will be worthwhile in depicting a well-organized picture for host-pathogen interplay during the malaria infection and may also provide some clues for the development of novel anti-malarial therapies. PMID:26925057

  7. [Heart surgery in a female patient with blood group Oh (Bombay phenotype)].

    PubMed

    Schricker, K T; Neidhardt, B; Hacker, R; Kail, R

    1983-01-14

    A 62-year-old woman with stenosing coronary artery disease had the rare blood group Oh (Bombay phenotype). After prophylactic deep-freeze conservation of autologous blood, direct myocardial revascularization was successfully accomplished under extracorporeal circulation. Three deep-freeze units of erythrocyte concentrates were used. Both operation and postoperative wound healing progressed without complication.

  8. Human Erythrocyte PIG-A Assay: An Easily Monitored Index of Gene Mutation Requiring Low Volume Blood Samples

    PubMed Central

    Dertinger, Stephen D.; Avlasevich, Svetlana L.; Bemis, Jeffrey C.; Chen, Yuhchyau; MacGregor, James T.

    2015-01-01

    This laboratory has previously described a method for scoring the incidence of rodent blood Pig-a mutant phenotype erythrocytes using immunomag-netic separation in conjunction with flow cytometric analysis (In Vivo MutaFlow®). The current work extends this approach to human blood. The frequencies of CD59- and CD55-negative reticulo-cytes (RETCD59−/CD55−) and erythrocytes (RBCCD59−/CD55−) seve as phenotypic reporters of PIG-A gene mutation. Immunomagnetic separation was found to provide an effective means of increasing the number of reticulocytes and erythro-cytes evaluated. Technical replicates were utilized to provide a sufficient number of cells for precise scoring while at the same time controlling for procedural accuracy by allowing comparison of replicate values. Cold whole blood samples could be held for at least one week without affecting reticulo-cyte, RETCD59−/CD55− or RBCCD59−/CD55− frequencies. Specimens from a total of 52 nonsmoking, self-reported healthy adult subjects were evaluated. The mean frequency of RETCD59−/CD55− and RBCCD592−/CD55− were 6.0 × 10−6 and 2.9 × 10−6, respectively. The difference is consistent with a modest selective pressure against mutant phenotype erythrocytes in the circulation, and suggests advantages of studying both populations of erythrocytes. Whereas intra-subject variability was low, inter-subject variability was relatively high, with RETCD59−/CD55− frequencies differing by more than 30-fold. There was an apparent correlation between age and mutant cell frequencies. Taken together, the results indicate that the frequency of human PIG-A mutant phenotype cells can be efficiently and reliably estimated using a labeling and analysis protocol that is well established for rodent-based studies. The applicability of the assay across species, its simplicity and statistical power, and the relatively non-invasive nature of the assay should benefit myriad research areas involving DNA damage

  9. Light-induced protoporphyrin release from erythrocytes in erythropoietic protoporphyria

    SciTech Connect

    Sandberg, S.; Brun, A.

    1982-09-01

    The photohemolysis of normal erythrocytes incubated with protoporphyrin is reduced in the presence of albumin. When globin is added to normal erythrocytes loaded with protoporphyrin, protoporphyrin is bound to globin. During irradiation protoporphyrin moves from globin to the erythrocyte membrane and photohemolysis is initiated. Erythrocytes in patients with erythropoietic protoporphyria contain large amounts of protoporphyrin bound to hemoglobin. Upon irradiation of these cells in the absence of albumin, 40% of protoporphyrin and 80% of hemoglobin is released after 240 kJ/m2. The released protoporphyrin is hemoglobin bound. In contrast, when albumin is present only 8% of hemoglobin is released whereas protoporphyrin is released to 76%. The released protoporphyrin is albumin bound. A hypothesis for the release of erythrocyte protoporphyrin in erythropoietic protoporphyria without simultaneous hemolysis is proposed. Upon irradiation protoporphyrin photodamages its binding sites on hemoglobin, moves through the plasma membrane, and is bound to albumin in plasma.

  10. Response of the rat erythrocyte to ozone exposure

    NASA Technical Reports Server (NTRS)

    Larkin, E. C.; Kimzey, S. L.; Siler, K.

    1978-01-01

    Sprague-Dawley rats were exposed to high (6-8 ppm) and moderate (1.5 ppm) amounts of ozone (O3) for various time periods. Response of the rat erythrocyte to ozone was monitored with red blood cell potassium (rubidium) influx studies, with storage stress combined with ultrastructural studies and with levels of erythrocyte glutathione peroxidase and superoxide dismutase. Erythrocytes of rats exposed to O3 showed no significant changes either in their potassium influx or in their glutathione peroxidase and superoxide dismutase activities compared to controls. Erythrocyte differential counts on O3-exposed animals showed significant changes initially as well as following storage stress compared to controls. Rats exposed to 8 ppm O3 for 4 h showed a marked increase in echinocytes. These consistent transformations from discocytes to echinocytes following O3 exposure suggest latent erythrocyte damage has occurred.

  11. Encapsulation of thiosulfate: cyanide sulfurtransferase by mouse erythrocytes

    SciTech Connect

    Leung, P.; Ray, L.E.; Sander, C.; Way, J.L.; Sylvester, D.M.; Way, J.L.

    1986-03-30

    Murine carrier erythrocytes, prepared by hypotonic dialysis, were employed in the encapsulation of several compounds including (14C)sucrose, (3H)inulin, and bovine thiosulfate:cyanide sulfurtransferase (rhodanese), a mitochondrial enzyme which converts cyanide to thiocyanate. Approximately 30% of the added (14C)sucrose, (3H)inulin, and rhodanese was encapsulated by predialyzed erythrocytes, and a decrease in the mean corpuscular volume and mean corpuscular hemoglobin was observed. In the encapsulation of rhodanese a recovery of 95% of the erythrocytes was achieved and an 85% equilibrium was established. The addition of potassium cyanide (50 mM) to intact, rhodanese-loaded erythrocytes containing sodium thiosulfate resulted in its metabolism to thiocyanate. These results establish the potential use of erythrocytes as biodegradable drug carrier in drug antagonism.

  12. Ferrokinetic and erythrocyte survival studies in healthy and anemic cats

    SciTech Connect

    Madewell, B.R.; Holmes, P.H.; Onions, D.E.

    1983-03-01

    Erythrocyte survival and ferrokinetic studies were adapted to the cat. For 5 clinically healthy 4- to 9-month-old cats, mean /sup 51/Cr-labeled erythrocyte survival was 144 hours, and mean plasma /sup 59/Fe-labeled transferrin disappearance halftime was 51 minutes. Erythrocyte use of radioiron was rapid and efficient, with 50% to 80% of labeled iron incorporated into the erythron by 100 hours after injection into the cat. Six cats with feline leukemia virus infection were studied. For 2 cats with erythroid aplasia associated with C subgroup of feline leukemia virus, erythrocyte survival times were similar to those determined for the healthy cats, but plasma radioiron disappearance half time and erythrocyte use of radioiron were markedly diminished.

  13. Effect of solution non-ideality on erythrocyte volume regulation.

    PubMed

    Levin, R L; Cravalho, E G; Huggins, C E

    1977-03-01

    A non-ideal, hydrated, non-dilute pseudo-binary salt-protein-water solution model of the erythrocyte intracellular solution is presented to describe the osmotic behavior of human erythrocytes. Existing experimental activity data for salts and proteins in aqueous solutions are used to formulate van Laar type expressions for the solvent and solute activity coefficients. Reasonable estimates can therefore be made of the non-ideality of the erythrocyte intracellular solution over a wide range of osmolalities. Solution non-ideality is shown to affect significantly the degree of solute polarization within the erythrocyte intracellular solution during freezing. However, the non-ideality has very little effect upon the amount of water retained within erythrocytes cooled at sub-zero temperatures. PMID:16250333

  14. Parallel reductions in stomatin and Na,K-ATPase through the exosomal pathway during reticulocyte maturation in dogs: stomatin as a genotypic and phenotypic marker of high K(+) and low K(+) red cells.

    PubMed

    Komatsu, Tomohiko; Sato, Kota; Otsuka, Yayoi; Arashiki, Nobuto; Tanaka, Kohei; Tamahara, Satoshi; Ono, Ken-ichiro; Inaba, Mutsumi

    2010-07-01

    Dogs can be divided into two genetic groups (a minor HK phenotype and a major LK phenotype) based on erythrocyte monovalent cation concentrations, which are controlled by the putative hk and lk allelic genes. HK dogs retain Na,K-ATPase in their erythrocytes due to the high activity of the enzyme in their precursor cells, whereas total loss of reticulocyte Na,K-ATPase occurs in LK dogs. Here, we report that the levels of the lipid raft-associated membrane protein stomatin decrease in parallel with those of Na,K-ATPase during reticulocyte maturation due to its extrusion in exosomes. The stomatin content of HK reticulocytes is higher than that of LK reticulocytes, and remains in the erythrocytes at levels compatible with that in human erythrocytes. However, it is almost absent from LK erythrocytes with the lk/lk genotype; similar to the deficiency seen in human red cells with overhydrated stomatocytosis. LK erythrocytes from hk/lk genotype dogs show reduced, but not negligible, levels of stomatin. These results indicate that the erythrocyte stomatin level is a suitable genotypic marker for the HK/LK red cell phenotype, and suggests a functional association between stomatin and Na,K-ATPase. The absence of morphological abnormalities in the erythrocytes of stomatin-deficient LK dogs also confirms that stomatin deficiency and stomatocytic shape change are independent from each other.

  15. URINARY MUTAGENESIS AS AN EXPOSURE BIOMARKER OF COOKED-MEAT-ASSOCIATED MUTAGENS: INFLUENCE OF COOKING TEMPERATURE, PHENOTYPE, AND GENOTYPE IN A CONTROLLED METABOLIC FEEDING STUDY

    EPA Science Inventory

    ABSTRACT
    We evaluated urinary mutagenicity and selected phenotypes and genotypes in 60 subjects in a metabolic feeding study in which meat cooked at low temperature (100oC) was consumed for 1 week followed by meat cooked at high temperature (250oC) the second week. Meat coo...

  16. Genotype-Phenotype Correlations in Multiple Sclerosis: "HLA" Genes Influence Disease Severity Inferred by [superscript 1]HMR Spectroscopy and MRI Measures

    ERIC Educational Resources Information Center

    Okuda, D. T.; Srinivasan, R.; Oksenberg, J. R.; Goodin, D. S.; Baranzini, S. E.; Beheshtian, A.; Waubant, E.; Zamvil, S. S.; Leppert, D.; Qualley, P.; Lincoln, R.; Gomez, R.; Caillier, S.; George, M.; Wang, J.; Nelson, S. J.; Cree, B. A. C.; Hauser, S. L.; Pelletier, D.

    2009-01-01

    Genetic susceptibility to multiple sclerosis (MS) is associated with the human leukocyte antigen (HLA) "DRB1*1501" allele. Here we show a clear association between DRB1*1501 carrier status and four domains of disease severity in an investigation of genotype-phenotype associations in 505 robust, clinically well characterized MS patients evaluated…

  17. Differences in the adhesive properties of Neisseria meningitidis for human buccal epithelial cells and erythrocytes.

    PubMed Central

    Trust, T J; Gillespie, R M; Bhatti, A R; White, L A

    1983-01-01

    The ability of clinical and carrier isolates of Neisseria meningitidis to adhere to human buccal epithelial cells and erythrocytes was investigated. Four of the 10 fimbriated strains were able to hemagglutinate. Serial subculture of three of these strains resulted in a loss of ability to hemagglutinate and was coincident with a loss of fimbriation. Other fimbriated strains were unable to hemagglutinate but did adhere to buccal epithelial cells. Subculture of one of these strains for as many as 42 passages did not result in loss of fimbriation or ability to adhere to buccal epithelial cells. The attachment of this strain to buccal epithelial cells was inhibited by glycoconjugates. Further, pH exerted different influences on the attachment of hemagglutinating and non-hemagglutinating fimbriated strains to buccal epithelial cells and erythrocytes. The results suggest that different fimbrial mechanisms are involved in the attachment of N. meningitidis to different cell types and that hemagglutination is not an absolute test for fimbriae. PMID:6134676

  18. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    SciTech Connect

    Weinstein, R.; Zhou, M.A.; Bartlett-Pandite, A.; Wenc, K. )

    1990-11-15

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling.

  19. Structural and compositional changes in erythrocyte membrane of obese compared to normal-weight adolescents.

    PubMed

    Perona, Javier S; González-Jiménez, Emilio; Aguilar-Cordero, María J; Sureda, Antonio; Barceló, Francisca

    2013-12-01

    Unhealthy dietary habits are key determinants of obesity in adolescents. Assuming that dietary fat profile influences membrane lipid composition, the aim of this study was to analyze structural changes in the erythrocyte membrane of obese compared to normal-weight adolescents. The study was conducted in a group of 11 obese and 11 normal-weight adolescent subjects. The lipid profile, lipid peroxidation and acetylcholinesterase enzyme (AChE) activity were analyzed by conventional methods. The structural properties of reconstituted erythrocyte membrane were characterized by X-ray diffraction. Erythrocyte membrane from obese adolescents had a lipid profile characterized by a higher cholesterol/phospholipid ratio, an increase in saturated fatty acid and a decrease in monounsaturated and n-6 polyunsaturated fatty acid concentrations. Differences in lipid content were associated with changes in the structural properties of reconstituted membranes and the oxidative damage of erythrocyte membrane. The lower oxidative level shown in the obese group (0.15 ± 0.04 vs. 0.20 ± 0.06 nmol/mg for conjugated diene concentrations and 2.43 ± 0.25 vs. 2.83 ± 0.31 nmol/mg protein for malondialdehyde levels) was related to a lower unsaturation index. These changes in membrane structural properties were accompanied by a lower AChE activity (1.64 ± 0.13 vs. 1.91 ± 0.24 nmol AChE/[min mg protein]) in the obese group. The consequences of unhealthy dietary habits in adolescents are reflected in the membrane structural properties and may influence membrane-associated protein activities and functions.

  20. Artemisinin-Resistant Plasmodium falciparum Parasites Exhibit Altered Patterns of Development in Infected Erythrocytes

    PubMed Central

    Hott, Amanda; Casandra, Debora; Sparks, Kansas N.; Morton, Lindsay C.; Castanares, Geocel-Grace; Rutter, Amanda

    2015-01-01

    Artemisinin derivatives are used in combination with other antimalarial drugs for treatment of multidrug-resistant malaria worldwide. Clinical resistance to artemisinin recently emerged in southeast Asia, yet in vitro phenotypes for discerning mechanism(s) of resistance remain elusive. Here, we describe novel phenotypic resistance traits expressed by artemisinin-resistant Plasmodium falciparum. The resistant parasites exhibit altered patterns of development that result in reduced exposure to drug at the most susceptible stage of development in erythrocytes (trophozoites) and increased exposure in the most resistant stage (rings). In addition, a novel in vitro delayed clearance assay (DCA) that assesses drug effects on asexual stages was found to correlate with parasite clearance half-life in vivo as well as with mutations in the Kelch domain gene associated with resistance (Pf3D7_1343700). Importantly, all of the resistance phenotypes were stable in cloned parasites for more than 2 years without drug pressure. The results demonstrate artemisinin-resistant P. falciparum has evolved a novel mechanism of phenotypic resistance to artemisinin drugs linked to abnormal cell cycle regulation. These results offer insights into a novel mechanism of drug resistance in P. falciparum and new tools for monitoring the spread of artemisinin resistance. PMID:25779582

  1. Methane-induced haemolysis of human erythrocytes.

    PubMed Central

    Batliwala, H; Somasundaram, T; Uzgiris, E E; Makowski, L

    1995-01-01

    Human erythrocytes were exposed to high concentrations of methane and nitrogen through the application of elevated partial pressures of these gas molecules. Cell leakage (haemolysis) was measured for cells exposed to these gases under a wide range of experimental conditions. Application of methane produces haemolysis at pressures far below the hydrostatic pressures known to disrupt membrane or protein structure. The effects of changes in buffer, temperature, diffusion rate and detergents were studied. Methane acts co-operatively with detergents to produce haemolysis at much lower detergent concentration than is required in the absence of methane or in the presence of nitrogen. At sufficiently high concentrations of methane, all cells are haemolysed. Increased temperature enhances the effect. Methane produces 50% haemolysis at a concentration of about 0.33 M compared with about 7.5 M methanol required for the same degree of haemolysis. Images Figure 1 PMID:7733880

  2. Interaction between plant polyphenols and the erythrocyte membrane.

    PubMed

    Cyboran, Sylwia; Oszmiański, Jan; Kleszczyńska, Halina

    2012-03-01

    The purpose of these studies was to determine the effect of polyphenols contained in extracts from apple, strawberry and blackcurrant on the properties of the erythrocyte membrane, treated as a model of the biological membrane. To this end, the effect of the substances used on hemolysis, osmotic resistance and shape of erythrocytes, and on packing order in the hydrophilic region of the erythrocyte membrane was studied. The investigation was performed with spectrophotometric and fluorimetric methods, and using the optical microscope. The hemolytic studies have shown that the extracts do not induce hemolysis at the concentrations used. The results obtained from the spectrophotometric measurements of osmotic resistance of erythrocytes showed that the polyphenols contained in the extracts cause an increase in the resistance, rendering them less prone to hemolysis in hypotonic solutions of sodium chloride. The fluorimetric studies indicate that the used substances cause a decrease of packing order in the hydrophilic area of membrane lipids. The observations of erythrocyte shapes in a biological optical microscope have shown that, as a result of the substances' action, the erythrocytes become mostly echinocytes, which means that the polyphenols of the extracts localize in the outer lipid monolayer of the erythrocyte membrane. The results obtained indicate that, in the concentration range used, the plant extracts are incorporated into the hydrophilic area of the membrane, modifying its properties.

  3. Is nitrotyrosine generated in human erythrocytes in circulation?

    PubMed

    Kikugawa, K; Nakauchi, K; Beppu, M; Hiramoto, K; Ando, K; Hayakawa, M

    2000-04-01

    Nitrotyrosine is considered a stable biomarker of reactive nitrogen species, including nitrogen dioxide (NO2) and peroxynitrous acid (ONOOH) in biomaterials. There are inconsistent observations on the detection of free and protein-associated nitrotyrosine in normal human plasma. Human erythrocytes, differentiated from erythrocyte precursor cells in the bone marrow, circulating in the body for an average of 120 d, and finally removed by spleen macrophages, may be exposed to reactive nitrogen species. In the present study, membrane proteins and hemoglobin from the senescent erythrocyte population were compared with those from young erythrocytes separated from the same individuals in their nitrotyrosine presence using newly prepared rabbit polyclonal anti-nitrotyrosine-ribonuclease A and anti-nitro(N-butoxycarbonyl)tyrosine-bovine serum albumin antibodies. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the membranes and hemoglobin, and subsequent Western blot analysis, showed that these antibodies only slightly bind to the bands of the proteins from both young and senescent erythrocytes, whereas these antibodies definitely bind to the protein bands of membranes and hemoglobin nitrated by NO2 or ONOOH in vitro. This result indicates that nitrotyrosine is not detected in the membrane proteins and hemoglobin in human normal erythrocytes in circulation. However, this does not conclude that erythrocytes are not exposed to reactive nitrogen species in the circulation.

  4. Erythrocyte hemodynamics in stenotic microvessels: A numerical investigation

    NASA Astrophysics Data System (ADS)

    Wang, T.; Xing, Z. W.

    2013-10-01

    This paper presents a two-dimensional numerical investigation of deformation and motion of erythrocytes in stenotic microvessels using the immersed boundary-fictitious domain method. The erythrocytes were modeled as biconcave-shaped closed membranes filled with cytoplasm. We studied the biophysical characteristics of human erythrocytes traversing constricted microchannels with the narrowest cross-sectional diameter as small as 3 μm. The effects of essential parameters, namely, stenosis severity, shape of the erythrocytes, and erythrocyte membrane stiffness, were simulated and analyzed in this study. Moreover, simulations were performed to discuss conditions associated with the shape transitions of the cells along with the relative effects of radial position and initial orientation of erythrocytes, membrane stiffness, and plasma environments. The simulation results were compared with existing experiment findings whenever possible, and the physical insights obtained were discussed. The proposed model successfully simulated rheological behaviors of erythrocytes in microscale flow and thus is applicable to a large class of problems involving fluid flow with complex geometry and fluid-cell interactions. Our study would be helpful for further understanding of pathology of malaria and some other blood disorders.

  5. Structural effects of titanium citrate on the human erythrocyte membrane.

    PubMed

    Suwalsky, M; Villena, F; Norris, B; Soto, M A; Sotomayor, C P; Messori, L; Zatta, P

    2005-03-01

    The structural effects of titanium citrate on the human erythrocyte membrane were studied through its interaction with intact erythrocytes and isolated unsealed human erythrocyte membranes (IUM). The studies were carried out by scanning electron microscopy and fluorescence spectroscopy, respectively. Titanium citrate induced shape changes in erythrocytes, which were damaged and ruptured leaving empty and retracted membranes. Fluorescence spectroscopy measurements in IUM indicated a disordering effect at both the polar head group and the acyl chain packing arrangements of the membrane phospholipid bilayer. Titanium citrate also interacted with molecular models of the erythrocyte membrane consisting in bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representing classes of phospholipids located in the outer and inner monolayers of the erythrocyte membrane, respectively. X-ray diffraction indicated that titanium citrate induced structural perturbation of the polar head group and of the hydrophobic acyl regions of DMPC, while the effects on DMPE bilayers were negligible. This conclusion is supported by fluorescence spectroscopy measurements on DMPC large unilamellar vesicles. All these findings indicate that the structural perturbations induced by titanium to human erythrocytes can be extended to other cells, thereby affecting their functions. PMID:15708797

  6. Erythrocyte hemodynamics in stenotic microvessels: A numerical investigation

    NASA Astrophysics Data System (ADS)

    Wang, Tong; Xing, Zhongwen

    2014-03-01

    This paper presents a two-dimensional numerical investigation of deformation and motion of erythrocytes in stenotic microvessels using the immersed boundary-fictitious domain method. The erythrocytes were modeled as biconcave-shaped closed membranes filled with cytoplasm. We studied the biophysical characteristics of human erythrocytes traversing constricted microchannels with the narrowest cross-sectional diameter as small as 3 μm. The effects of essential parameters, namely, stenosis severity, shape of the erythrocytes, and erythrocyte membrane stiffness, were simulated and analyzed in this study. Moreover, simulations were performed to discuss conditions associated with the shape transitions of the cells along with the relative effects of radial position and initial orientation of erythrocytes, membrane stiffness, and plasma environments. The simulation results were compared with existing experiment findings whenever possible, and the physical insights obtained were discussed. The proposed model successfully simulated rheological behaviors of erythrocytes in microscale flow and thus is applicable to a large class of problems involving fluid flow with complex geometry and fluid-cell interactions. Our study would be helpful for further understanding of pathology of malaria and some other blood disorders.

  7. Influence of the PROP bitter taste phenotype and eating attitudes on energy intake and weight status in pre-adolescents: a 6-year follow-up study.

    PubMed

    Oftedal, Katherine Nolen; Tepper, Beverly J

    2013-06-13

    The PROP bitter-taste phenotype is a marker for food preferences and eating behavior, and may associate with differences in body weight in children. Previous work has shown that PROP status in combination with eating attitudes are better predictors of weight status in preadolescents, than either factor alone. However, no studies have examined the role of PROP phenotypes in body weight change in children over time. The primary objective of this study was to investigate current weight status and change in weight status in children from preschool (baseline) to preadolescence as a function of eating attitudes and PROP phenotype. Other measures included self-reported food intakes and physical activity by activity monitor. Seventy-three lean (BMI percentile=57.7±3.2%) children with mean age=10.3±0.5yrs, participated in the follow up. There were no group differences in energy intake, current BMI-percentile or change in BMI percentile from baseline by PROP phenotype in either boys or girls. However, there was a trend for non-taster girls to show a downward shift in BMI-percentile at follow up. Hierarchical regression analysis revealed that baseline BMI percentile and physical activity energy expenditure were the strongest predictors of current weight (28.5% variance),followed by child restraint, the taster×gender interaction, and the maternal BMI×maternal emotional eating interaction, accounting for 7.1%, 6.0% and 4.8% of variance in the model, respectively. These findings suggest that PROP status and eating attitudes are modest predictors of weight status in preadolescent children.

  8. Clinical factors influencing phenotype of HCMV-specific CD8+ T cells and HCMV-induced interferon-gamma production after allogeneic stem cells transplantation.

    PubMed

    Gayoso, Inmaculada; Cantisán, Sara; Cerrato, Carolina; Sánchez-García, Joaquín; Martin, Carmen; Solana, Rafael; Torres-Gomez, Antonio; Torre-Cisneros, Julian

    2013-01-01

    Human cytomegalovirus (HCMV) infection causes significant morbidity and mortality after hematopoietic stem cell transplantation (HSCT). In this work, we characterized the phenotype and interferon-gamma (INF-γ) production of HCMV-specific T cells using QuantiFERON-HCMV assay in 26 patients 6 months after HSCT. We analysed whether these two parameters were associated with clinical variables. Our results showed that the patients receiving stem cells from donors ≥40 years old were 12 times more likely to have HCMV-specific CD8+ T cells with "differentiated phenotype" (CD45RA+CCR7+ ≤6.7% and CD28+ ≤30%) than patients grafted from donors <40 years old (OR = 12; P = 0.014). In addition, a detectable IFN-γ production in response to HCMV peptides (cutoff 0.2 IU/mL IFN-γ; "reactive" QuantiFERON-HCMV test) was statistically associated with HCMV replication after transplantation (OR = 11; P = 0.026), recipients ≥40 versus <40 years old (OR = 11; P = 0.026), and the use of peripheral blood versus bone marrow as stem cell source (OR = 17.5; P = 0.024). In conclusion, donor age is the only factor significantly associated with the presence of the "differentiated phenotype" in HCMV-specific CD8+ T cells, whereas HCMV replication after transplantation, recipient age, and stem cell source are the factors associated with the production of IFN-γ in response to HCMV epitopes.

  9. Participation of free oxygen radicals in damage of porcine erythrocytes

    SciTech Connect

    Jozwiak, J.; Helszer, Z.

    1981-10-01

    Gamma radiation causes disturbances in energy metabolism, decreases in (Na/sup +/-K/sup +/)-ATPase, Mg/sup 2 +/-APTase activity, and increase in the degree of hemolysis in porcine erythrocytes. Our results indicated a contribution of exogenous free radicals in radiation damage to porcine erythrocytes. In the presence of biological and chemical radioprotectors a protective effect with respect to ATPase activity and energy metabolism was observed in the presence of catalase, histidine, glucose, and sulfhydryl compounds. It appears that radiation damage to porcine erythrocytes is due to the action of various radicals formed upon irradiation which react at different rates with various cell constituents.

  10. Erythrocyte survival studies in a rat myelogenous leukemia

    SciTech Connect

    Derelanko, M.J.; Meagher, R.C.; Lobue, J.; Khouri, J.A.; Gordon, A.S.

    1982-11-01

    To determine the extent intrinsic erythrocyte defects and/or extrinsic factors were involved in anemia of rats bearing Shay chloroleukemia (SCL), survival of /sup 3/H-DFP labeled erythrocytes was studied in leukemic and nonleukemic hosts. Red blood cells labeled before induction of leukemia, were rapidly lost from the peripheral circulation of SCL rats in terminal stages of disease. However, labeled erythrocytes from terminal SCL animals displayed normal lifespans when transfused into nonleukemic controls. Thus the anemia of this leukemia probably resulted from extrinsic factors associated with the leukemic process. Hemorrhage appeared to be primarily responsible for the anemia of this disease.

  11. Mature Erythrocytes of Iguana iguana (Squamata, Iguanidae) Possess Functional Mitochondria.

    PubMed

    Di Giacomo, Giuseppina; Campello, Silvia; Corrado, Mauro; Di Giambattista, Livia; Cirotti, Claudia; Filomeni, Giuseppe; Gentile, Gabriele

    2015-01-01

    Electron microscopy analyses of Iguana iguana blood preparations revealed the presence of mitochondria within erythrocytes with well-structured cristae. Fluorescence microscopy analyses upon incubation with phalloidin-FITC, Hoechst 33342 and mitochondrial transmembrane potential (Δψm)-sensitive probe MitoTracker Red indicated that mitochondria i) widely occur in erythrocytes, ii) are polarized, and iii) seem to be preferentially confined at a "perinuclear" region, as confirmed by electron microscopy. The analysis of NADH-dependent oxygen consumption showed that red blood cells retain the capability to consume oxygen, thereby providing compelling evidence that mitochondria of Iguana erythrocytes are functional and capable to perform oxidative phosphorylation.

  12. Comparison of in vivo effect of inorganic lead and cadmium on glutathione reductase system and delta-aminolevulinate dehydratase in human erythrocytes.

    PubMed Central

    Roels, H A; Buchet, J P; Lauwerys, R R; Sonnet, J

    1975-01-01

    The activity of delta-aminolevulinate dehydratase (ALAD) of erythrocytes, the lead (Pb-B) and cadmium (Cd-B) concentration in whole blood, the content of reduced glutathion (GSH) in erythrocytes, and the regeneration rate of GSH by intact erythrocytes were measured during an epidemiological survey of 84 men employed in a Belgian cadmium and lead producing plant. A control group of 26 persons (students and laboratory staff) was also examined. The logarithm of the ALAD activity is highly inversely correlated with log Pb-B (r = -0.760) but no correlation was found with log Cd-B. There exists a significant negative correlation between GSH and log Pb-B (r = -0.423) but not between GSH AND LOG Cd-B. The apparently good relationship between log ALAD and GSH disappeared completely by holding log Pb-B constant, but log ALAD remained highly inversely correlated with log Pb-B when standardized for GSH concentration (r = -0.748). In vivo investigation of the GSH regeneration rate of intact erythrocytes demonstrated clearly that the overall activity of the glutathione oxidation-reduction pathways is not impaired in Pb and Cd-exposed workers with significantly increased Pb-B and Cd-B, since their initial GSH regeneration rate (first 15 minutes) was identical with that of the control group. Results of similar in vitro experiments in which control whole blood was incubated before-hand with Pb2+ or Cd2+, or both, reinforce this conclusion. Since increased Cd-B and Pb-B do not influence the glutathione reductase system of erythrocytes, and since endogenous erythrocyte GSH is not correlated with Cd-B, the moderate decrease in endogenous erythrocyte Gsh found in Pb-exposed workers might result from a Pb-induced impairment for the erythrocyte mechanism for glutathione synthesis. PMID:1156566

  13. Effects of lithium on the human erythrocyte membrane and molecular models.

    PubMed

    Suwalsky, Mario; Fierro, Paulo; Villena, Fernando; Sotomayor, Carlos P

    2007-08-01

    The mechanism whereby lithium carbonate controls manic episodes and possibly influences affective disorders is not yet known. There is evidence, however, that lithium alters sodium transport and may interfere with ion exchange mechanisms and nerve conduction. For these reasons it was thought of interest to study its perturbing effects upon membrane structures. The effects of lithium carbonate (Li+) on the human erythrocyte membrane and molecular models have been investigated. The molecular models consisted in bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representing classes of phospholipids located in the outer and inner monolayers of the erythrocyte membrane, respectively. This report presents the following evidence that Li+ interacts with cell membranes: a) X-ray diffraction indicated that Li+ induced structural perturbation of the polar head group and of the hydrophobic acyl regions of DMPC and DMPE; b) experiments performed on DMPC large unilamellar vesicles (LUV) by fluorescence spectroscopy also showed that Li+ interacted with the lipid polar groups and hydrophobic acyl chains, and c) in scanning electron microscopy (SEM) studies on intact human erythrocytes the formation of echinocytes was observed, effect that might be due to the insertion of Li+ in the outer monolayer of the red cell membrane. PMID:17532553

  14. Acetylcholinesterase from Human Erythrocytes as a Surrogate Biomarker of Lead Induced Neurotoxicity

    PubMed Central

    Gupta, Vivek Kumar; Pal, Rajnish; Siddiqi, Nikhat Jamal; Sharma, Bechan

    2015-01-01

    Lead induced neurotoxicity in the people engaged in different occupations has received wide attention but very little studies have been carried out to monitor occupational neurotoxicity directly due to lead exposure using biochemical methods. In the present paper an endeavour has been made in order to assess the lead mediated neurotoxicity by in vitro assay of the activity of acetylcholinesterase (AChE) from human erythrocytes in presence of different concentrations of lead. The results suggested that the activity of this enzyme was localized in membrane bound fraction and it was found to be highly stable up to 30 days when stored at −20°C in phosphate buffer (50 mM, pH 7.4) containing 0.2% Triton X-100. The erythrocyte's AChE exhibited Km for acetylcholinesterase to be 0.1 mM. Lead caused sharp inhibition of the enzyme and its IC50 value was computed to be 1.34 mM. The inhibition of the enzyme by lead was found to be of uncompetitive type (Ki value, 3.6 mM) which negatively influenced both the Vmax and the enzyme-substrate binding affinity. Taken together, these results indicate that AChE from human erythrocytes could be exploited as a surrogate biomarker of lead induced neurotoxicity particularly in the people occupationally exposed to lead. PMID:26600946

  15. Effects of an angelica extract on human erythrocyte aggregation, deformation and osmotic fragility.

    PubMed

    Wang, X; Wei, L; Ouyang, J P; Muller, S; Gentils, M; Cauchois, G; Stoltz, J F

    2001-01-01

    In Chinese traditional medicine, angelica is widely used for its known clinical effects of ameliorating blood microcirculation. But the mechanism of these beneficial effects still remains unclear. In this work the rheological behaviour of human erythrocytes treated by angelica was studied in vitro. Normal RBCs incubated with an angelica extract at different concentrations (5, 10 or 20 mg/ml) for 60 min at 37 degrees C and then their aggregation, deformation and osmotic fragility were measured with different recently developed optical techniques, namely Erythroaggregometer (Regulest, Florange, France), LORCA (Mechatronics, Amsterdam) and Fragilimeter (Regulest, Florange, France). Experimental results show that angelica (20 mg/ml) significantly decreased normal RBCs' aggregation speed (p<0.01) and could inhibit the hyperaggregability caused by dextran 500. However, the strength of normal RBCs aggregates were not influenced by angelica. When a calcium ionophore A23187 (1.9 microM) was used to harden cell membrane, angelica (20 mg/ml) could significantly (p<0.01) protect erythrocytes against the loss of their deformability even it had no effects on normal RBCs deformation. Finally angelica (5 and 10 mg/ml) decreased significantly (p<0.01) normal RBCs osmotic fragility. In conclusion angelica plays a rheologically active role on human erythrocytes, and this study suggests a possible mechanism for angelica's positive effects against certain cardiovascular diseases.

  16. Erythrocyte and leukocyte: two partners in bacteria killing.

    PubMed

    Minasyan, Hayk A

    2014-01-01

    Leukocytes can't perform phagocytosis in blood stream. Blood velocity prevents phagocytosis because there is no time for leukocyte to recognize and catch bacteria. Bloodstream clearance from pathogens is performed by erythrocytes. During motion in bloodstream erythrocytes become charged by triboelectric effect. This charge attracts bacteria and fixes them on the surface of erythrocyte, then bacteria are engulfed and killed by hemoglobin oxygen. In bloodstream, leukocyte thin-wrinkled elastic membrane can't be charged by triboelectric effect and so leukocyte can't catch bacteria by means of electrostatic attraction force. Leukocytes engulf and kill bacteria out of blood circulatory system: in tissues, lymph nodes, slow velocity lymph, etc. Erythrocyte and leukocyte are bactericidal partners: the first kills bacteria in bloodstream, the second kills them locally, out of blood circulation.

  17. Subcutaneous administration of carrier erythrocytes: slow release of entrapped agent

    SciTech Connect

    DeLoach, J.R.; Corrier, D.E.

    1988-08-01

    Carrier erythrocytes administered subcutaneously in mice release encapsulated molecules at the injection site and through cells that escape the injection site. One day postinjection, the efflux of encapsulated (/sup 14/C)sucrose, (/sup 3/H)inulin, and /sup 51/Cr-hemoglobin from the injection site was 45, 55, and 65%, respectively. Intact carrier erythrocytes escaped the injection site and entered the blood circulation carrying with them the encapsulated molecules. Most of the encapsulated (/sup 3/H)inulin that reached whole blood circulated within erythrocytes. Small but measurable numbers of encapsulated molecules were trapped within lymph nodes. Subcutaneous injection of carrier erythrocytes may allow for limited extravascular tissue targeting of drugs.

  18. Exposure to ozone and erythrocyte osmotic resistance in the rat

    SciTech Connect

    Ikemi, Y.; Ohmori, K.; Ito, T.; Osaka, F.; Matuura, Y. )

    1992-10-01

    In order to learn the biological effect of photochemical oxidants on living bodies, we exposed newborn and adult rats, of both sexes, to ozone at a concentration of 0.25 ppm, which can be encountered in an urban environment, and then measured the osmotic resistance of their erythrocytes. The results of experiments using newborn rats indicated a positive increase in the osmotic resistance of erythrocytes in whole blood following ozone exposure for 4 weeks. An increase in the osmotic resistance of erythrocytes in the top part obtained by centrifugation was observed following ozone exposure for 12 weeks. This tendency was especially evident among male rats. On the other hand, no increase in the osmotic resistance of erythrocytes was recognized in the adult animals which had been exposed to the same concentration of ozone for 18 months.

  19. Malaria: a tumour necrosis factor inhibitor from parasitized erythrocytes.

    PubMed Central

    Sheikh, N A; Caro, H N; Taverne, J; Playfair, J H; Rademacher, T W

    1996-01-01

    The excessive production of tumour necrosis factor (TNF) is associated with the pathology of blood-stage malaria and phosphatidylinositol-containing phospholipid antigens from parasitized erythrocytes stimulate its secretion by macrophages, thus acting as toxins. This brief report describes some properties of an inhibitor present in lysates from erythrocytes infected with malarial parasites that blocked the detection of recombinant TNF in an enzyme-linked immunosorbent assay and diminished or abolished the cytotoxicity of TNF. It was not found in control lysates of normal erythrocytes. Its addition to macrophage cultures stimulated by toxic malarial preparations or by bacterial lipopolysaccharide also blocked the detection of TNF. These findings may explain the contradictory results obtained from different assays for TNF, and emphasize the need for caution when interpreting the results of a single assay system. If released when parasitized erythrocytes rupture in vivo, the inhibitor could help protect both parasite and host from the damaging effects of TNF. PMID:8778034

  20. The anticancer drug cisplatin interacts with the human erythrocyte membrane.

    PubMed

    Suwalsky, M; Hernández, P; Villena, F; Sotomayor, C P

    2000-01-01

    Drugs which exert their effects by interacting with DNA cause structural and functional membrane alterations which may be essential for growth inhibition by these agents. This paper describes the interaction of cisplatin with the human erythrocyte membrane and models constituted by bilayers of dimyristoylphosphatidylethanolamine (DMPE) and diacylphosphatidylserine (DAPS), representative of phospholipid classes located in the inner monolayer of the erythrocyte membrane, and of dimyristoylphosphatidylcholine (DMPC), a class present in its outer monolayer. Cisplatin ability to perturb DMPE, DAPS and DMPC bilayer structures was determined by X-ray diffraction and fluorescence spectroscopy. Electron microscopy disclosed that human erythrocytes incubated with 35 microM cisplatin, which is its therapeutical concentration in serum, developed cup-shaped forms (stomatocytes). According to the bilayer couple hypothesis, this means that the drug is inserted into the inner monolayer of the erythrocyte membrane, a conclusion supported by the studies on model systems. PMID:10928560

  1. [Erythrocytes and microvascular tone during acute traumatic haemorrhagic shock].

    PubMed

    Morel, N; Biais, M; Delaunay, F; Dubuisson, V; Cassone, O; Siméon, F; Morel, O; Janvier, G

    2013-05-01

    Haemorrhagic shock remains a leading cause of death in trauma patients. The concept of haematologic damage control is gradually taking place in the management of traumatic haemorrhagic shock. It is based primarily on the early implementation of a quality blood transfusion involving erythrocytes, plasmas and platelets transfusion. Red blood cell transfusion is mainly supported by the oxygen carrier properties of erythrocytes. However, it appears that erythrocytes ability to modulate the bioavailability of nitric oxide (NO) plays a major role in capillary opening and perfusion. Erythrocytes are also actively involved in the processes of hemostasis and coagulation. In this context, it seems difficult to define a threshold of hemoglobin concentration to determine the implementation of a blood transfusion in traumatic haemorrhagic shock.

  2. Fy(a)/Fy(b) antigen polymorphism in human erythrocyte Duffy antigen affects susceptibility to Plasmodium vivax malaria.

    PubMed

    King, Christopher L; Adams, John H; Xianli, Jia; Grimberg, Brian T; McHenry, Amy M; Greenberg, Lior J; Siddiqui, Asim; Howes, Rosalind E; da Silva-Nunes, Monica; Ferreira, Marcelo U; Zimmerman, Peter A

    2011-12-13

    Plasmodium vivax (Pv) is a major cause of human malaria and is increasing in public health importance compared with falciparum malaria. Pv is unique among human malarias in that invasion of erythrocytes is almost solely dependent on the red cell's surface receptor, known as the Duffy blood-group antigen (Fy). Fy is an important minor blood-group antigen that has two immunologically distinct alleles, referred to as Fy(a) or Fy(b), resulting from a single-point mutation. This mutation occurs within the binding domain of the parasite's red cell invasion ligand. Whether this polymorphism affects susceptibility to clinical vivax malaria is unknown. Here we show that Fy(a), compared with Fy(b), significantly diminishes binding of Pv Duffy binding protein (PvDBP) at the erythrocyte surface, and is associated with a reduced risk of clinical Pv in humans. Erythrocytes expressing Fy(a) had 41-50% lower binding compared with Fy(b) cells and showed an increased ability of naturally occurring or artificially induced antibodies to block binding of PvDBP to their surface. Individuals with the Fy(a+b-) phenotype demonstrated a 30-80% reduced risk of clinical vivax, but not falciparum malaria in a prospective cohort study in the Brazilian Amazon. The Fy(a+b-) phenotype, predominant in Southeast Asian and many American populations, would confer a selective advantage against vivax malaria. Our results also suggest that efficacy of a PvDBP-based vaccine may differ among populations with different Fy phenotypes.

  3. Amodiaquine failure associated with erythrocytic glutathione in Plasmodium falciparum malaria

    PubMed Central

    Zuluaga, Lina; Pabón, Adriana; López, Carlos; Ochoa, Aleida; Blair, Silvia

    2007-01-01

    Objective To establish the relationship between production of glutathione and the therapeutic response to amodiaquine (AQ) monotherapy in Plasmodium falciparum non-complicated malaria patients. Methodology Therapeutic response to AQ was evaluated in 32 patients with falciparum malaria in two townships of Antioquia, Colombia, and followed-up for 28 days. For every patient, total glutathione and enzymatic activity (glutathione reductase, GR, and γ-glutamylcysteine synthetase, γ-GCS) were determined in parasitized erythrocytes, non-infected erythrocytes and free parasites, on the starting day (day zero, before ingestion of AQ) and on the day of failure (in case of occurrence). Results There was found an AQ failure of 31.25%. Independent of the therapeutic response, on the starting day and on the day of failure, lower total glutathione concentration and higher GR activities in parasitized erythrocytes were found, compared with non-infected erythrocytes (p < 0.003). In addition, only on the day of failure, γ-GCS activity of parasitized erythrocytes was higher, compared with that of healthy erythrocytes (p = 0.01). Parasitized and non-parasitized erythrocytes in therapeutic failure patients (TF) had higher total glutathione on the starting day compared with those of adequate clinical response (ACR) (p < 0.02). Parasitized erythrocytes of TF patients showed lower total glutathione on the failure day, compared with starting day (p = 0.017). No differences was seen in the GR and γ-GCS activities by compartment, neither between the two therapeutic response groups nor between the two treatment days. Conclusion This study is a first approach to explaining P. falciparum therapeutic failure in humans through differences in glutathione metabolism in TF and ACR patients. These results suggest a role for glutathione in the therapeutic failure to antimalarials. PMID:17451604

  4. Proteome analysis of the triton-insoluble erythrocyte membrane skeleton.

    PubMed

    Basu, Avik; Harper, Sandra; Pesciotta, Esther N; Speicher, Kaye D; Chakrabarti, Abhijit; Speicher, David W

    2015-10-14

    Erythrocyte shape and membrane integrity is imparted by the membrane skeleton, which can be isolated as a Triton X-100 insoluble structure that retains the biconcave shape of intact erythrocytes, indicating isolation of essentially intact membrane skeletons. These erythrocyte "Triton Skeletons" have been studied morphologically and biochemically, but unbiased proteome analysis of this substructure of the membrane has not been reported. In this study, different extraction buffers and in-depth proteome analyses were used to more fully define the protein composition of this functionally critical macromolecular complex. As expected, the major, well-characterized membrane skeleton proteins and their associated membrane anchors were recovered in good yield. But surprisingly, a substantial number of additional proteins that are not considered in erythrocyte membrane skeleton models were recovered in high yields, including myosin-9, lipid raft proteins (stomatin, flotillin1 and 2), multiple chaperone proteins (HSPs, protein disulfide isomerase and calnexin), and several other proteins. These results show that the membrane skeleton is substantially more complex than previous biochemical studies indicated, and it apparently has localized regions with unique protein compositions and functions. This comprehensive catalog of the membrane skeleton should lead to new insights into erythrocyte membrane biology and pathogenic mutations that perturb membrane stability. Biological significance Current models of erythrocyte membranes describe fairly simple homogenous structures that are incomplete. Proteome analysis of the erythrocyte membrane skeleton shows that it is quite complex and includes a substantial number of proteins whose roles and locations in the membrane are not well defined. Further elucidation of interactions involving these proteins and definition of microdomains in the membrane that contain these proteins should yield novel insights into how the membrane skeleton

  5. Low toxicity method of inhibiting sickling of sickle erythrocytes

    DOEpatents

    Packer, Lester; Bymun, Edwin N.

    1977-01-01

    A low toxicity method of inhibiting sickling of sickle erythrocytes which comprises intermixing the erythrocytes with an effective anti-sickling amount of a water-soluble imidoester of the formula RC(=NH)OR' wherein R is an alkyl group of 1 - 8 carbon atoms, particularly 1 - 4 carbon atoms, and R' is an alkyl group of 1 - 4 carbon atoms, specifically methyl or ethyl acetimidate.

  6. Reduced parasitemia observed with erythrocytes containing inositol hexaphosphate.

    PubMed Central

    Mintzer, C L; Deloron, P; Rice-Ficht, A; Durica, D; Struck, D K; Roessner, C A; Nicolau, C; Ihler, G M

    1988-01-01

    Chemicals entrapped in erythrocytes by hypotonic hemolysis can be assessed for possible antiparasitic activity both in vivo and in vitro, regardless of whether they are able to diffuse into erythrocytes readily. Inositol hexaphosphate, a highly charged compound, produced a dramatic lowering of the percentage of cells infected by Babesia microti in vivo and both B. microti and Plasmodium falciparum in vitro. Several possible mechanisms for this observation are discussed. PMID:3364957

  7. Proteome analysis of the triton-insoluble erythrocyte membrane skeleton.

    PubMed

    Basu, Avik; Harper, Sandra; Pesciotta, Esther N; Speicher, Kaye D; Chakrabarti, Abhijit; Speicher, David W

    2015-10-14

    Erythrocyte shape and membrane integrity is imparted by the membrane skeleton, which can be isolated as a Triton X-100 insoluble structure that retains the biconcave shape of intact erythrocytes, indicating isolation of essentially intact membrane skeletons. These erythrocyte "Triton Skeletons" have been studied morphologically and biochemically, but unbiased proteome analysis of this substructure of the membrane has not been reported. In this study, different extraction buffers and in-depth proteome analyses were used to more fully define the protein composition of this functionally critical macromolecular complex. As expected, the major, well-characterized membrane skeleton proteins and their associated membrane anchors were recovered in good yield. But surprisingly, a substantial number of additional proteins that are not considered in erythrocyte membrane skeleton models were recovered in high yields, including myosin-9, lipid raft proteins (stomatin, flotillin1 and 2), multiple chaperone proteins (HSPs, protein disulfide isomerase and calnexin), and several other proteins. These results show that the membrane skeleton is substantially more complex than previous biochemical studies indicated, and it apparently has localized regions with unique protein compositions and functions. This comprehensive catalog of the membrane skeleton should lead to new insights into erythrocyte membrane biology and pathogenic mutations that perturb membrane stability. Biological significance Current models of erythrocyte membranes describe fairly simple homogenous structures that are incomplete. Proteome analysis of the erythrocyte membrane skeleton shows that it is quite complex and includes a substantial number of proteins whose roles and locations in the membrane are not well defined. Further elucidation of interactions involving these proteins and definition of microdomains in the membrane that contain these proteins should yield novel insights into how the membrane skeleton

  8. Correlation-timing-based erythrocyte velocity measurement using CCD imagery

    NASA Astrophysics Data System (ADS)

    O'Reilly, William J.; Hudetz, Anthony

    2001-05-01

    An automated correlation method is introduced to estimate erythrocyte velocity component of erythrocyte flux within the cerebral capillary network. Erythrocyte flux, defined as the number of red blood cells passing through a plane orthogonal to the axis of erythrocyte flow in a vessel per unit time, is considered to be the closest index of capillary flow. Introduced previously is the two-point cross-correlation method, a method whereby a video photometric analyzer captures the voltage produced from two electronic windows placed over a vessel of interest. In our new method, instead of using electronic windows, we use a CCD array, focused on a two- dimensional projection of the three-dimensional capillary structure. Simulations of this method yields accurate velocity measurements at a measured cell intensity of .2 standard deviations above mean noise values or cell counts fewer than 30 cells per minute for image sequences of 180 frames captured over a time interval of three seconds. We conclude that with proper reduction in the measured standard deviation of noise and by increasing the percentage of fluorscently labeled erythrocytes injected into the rat, the correlation timing method of estimating erythrocyte velocity is an accurate substitute for hand-measured velocity calculation.

  9. [A family with an "Hm" phenotype transmitted over 3 generations].

    PubMed

    Salmon, C; Juszczak, G; Liberge, G; Lopez, M; Cartron, J P; Kling, C

    1978-02-01

    Hm phenotype represents a dissociation between a normal salivary expression of H substance and a very weakened expression of the antigen on red blood cells. Genetic analysis of the reported family reveals a dominant inheritance: Some members (Marie K..., Francette, Carmen) present a phenotype marked by a normal H enzyme but a deficient H antigen in erythrocyte membrane. Others Alice, Mathilde) have no expression of A1 antigen due to H substrate deficiency. H substance in salivary secretion is normal. In the other branch of this pedigree without consanguinity, Herbert presents an H substance deficiency, though quite different, as A1 antigen is expressed. In this family, Hm phenotype can be explained, without resorting to a Zm allele, by the expression of an exceptional allele at the H locus (like Am is an ABO allele). This hypothesis supports the possible polymorphism of H locus.

  10. Association between human erythrocyte calmodulin and the cytoplasmic surface of human erythrocyte membranes.

    PubMed

    Agre, P; Gardner, K; Bennett, V

    1983-05-25

    This report describes Ca2+-dependent binding of 125I-labeled calmodulin (125I-CaM) to erythrocyte membranes and identification of two new CaM-binding proteins. Erythrocyte CaM labeled with 125I-Bolton Hunter reagent fully activated erythrocyte (Ca2+ + Mg2+)-ATPase. 125I-CaM bound to CaM depleted membranes in a Ca2+-dependent manner with a Ka of 6 x 10(-8) M Ca2+ and maximum binding at 4 x 10(-7) M Ca2+. Only the cytoplasmic surface of the membrane bound 125I-CaM. Binding was inhibited by unlabeled CaM and by trifluoperazine. Reduction of the free Ca2+ concentration or addition of trifluoperazine caused a slow reversal of binding. Nanomolar 125I-CaM required several hours to reach binding equilibrium, but the rate was much faster at higher concentrations. Scatchard plots of binding were curvilinear, and a class of high affinity sites was identified with a KD of 0.5 nM and estimated capacity of 400 sites per cell equivalent for inside-out vesicles (IOVs). The high affinity sites of IOVs most likely correspond to Ca2+ transporter since: (a) Ka of activation of (Ca2+ + Mg2+)-ATPase and KD for binding were nearly identical, and (b) partial digestion of IOVs with alpha-chymotrypsin produced activation of the (Ca2+ + Mg2+)-ATPase with loss of the high affinity sites. 125I-CaM bound in solution to a class of binding proteins (KD approximately 55 nM, 7.3 pmol per mg of ghost protein) which were extracted from ghosts by low ionic strength incubation. Soluble binding proteins were covalently cross-linked to 125I-CaM with Lomant's reagent, and 2 bands of 8,000 and 40,000 Mr (Mr of CaM subtracted) and spectrin dimer were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiography. The 8,000 and 40,000 Mr proteins represent a previously unrecognized class of CaM-binding sites which may mediate unexplained Ca2+-induced effects in the erythrocyte.

  11. Diabetic Erythrocytes Test by Correlation Coefficient

    PubMed Central

    Korol, A.M; Foresto, P; Darrigo, M; Rosso, O.A

    2008-01-01

    Even when a healthy individual is studied, his/her erythrocytes in capillaries continually change their shape in a synchronized erratic fashion. In this work, the problem of characterizing the cell behavior is studied from the perspective of bounded correlated random walk, based on the assumption that diffractometric data involves both deterministic and stochastic components. The photometric readings are obtained by ektacytometry over several millions of shear elongated cells, using a home-made device called Erythrodeformeter. We have only a scalar signal and no governing equations; therefore the complete behavior has to be reconstructed in an artificial phase space. To analyze dynamics we used the technique of time delay coordinates suggested by Takens, May algorithm, and Fourier transform. The results suggest that on random-walk approach the samples from healthy controls exhibit significant differences from those from diabetic patients and these could allow us to claim that we have linked mathematical nonlinear tools with clinical aspects of diabetic erythrocytes’ rheological properties. PMID:19415139

  12. Immunity to erythrocytic stages of malarial parasites.

    PubMed

    Long, C A; Daly, T M; Kima, P; Srivastava, I

    1994-01-01

    In those individuals who live in endemic areas, immunity to malaria is slow to develop and stage-specific. The nature and antigenic specificity of this response, which may involve components of both cell-mediated and humoral immunity, is not well understood. Rodent models provide useful systems to explore the spectrum of host responses that may contribute to resolution of erythrocytic-stage infection or possibly to pathogenesis. Moreover, these models allow identification of plasmodial molecules that can induce different types of host responses. Two different mouse model systems, Plasmodium yoelii yoelii and P. chabaudi adami are presented. These have been selected because resolution of infection by P. yoelii yoelii has been shown to require B cell-dependent mechanisms, while control of acute P. chabaudi adami infection can be achieved by T cell-dependent mechanisms. A monoclonal antibody that provides passive protection to P. yoelii challenge infection has been shown to recognize the cysteine-rich, carboxyl-terminal region of the merozoite surface protein-1. This region, obtained in an appropriate configuration from recombinant Escherichia coli, can induce significant protective immune responses in naive mice. In contrast, cell-mediated immune mechanisms make a major contribution to resolution of asexual-stage P. chabaudi adami infection. An empirical approach using continuous flow electrophoresis has identified several low molecular weight plasmodial proteins that can induce partial protective responses in susceptible hosts. These observations are briefly discussed with respect to human malaria.

  13. Erythrocyte exchange and leukapheresis in pregnancy.

    PubMed

    Perseghin, Paolo

    2015-12-01

    Hematological diseases in pregnancy should be carefully managed with a multidisciplinary approach, which should include obstetrics, hematology and, in selected patients, apheresis professionals. Hematological malignancies in pregnant women are rare, but the attending physicians should be aware that the use of cytotoxic drugs, tyrosine-kinase inhibitors or differentiating agents such as all-trans retinoic acid (ATRA) during the first trimester of pregnancy might be teratogenic and, in turn, induce fetal abnormalities or abortion. Thus, in pregnant patients with either acute or chronic leukemia presenting with symptomatic hyperleukocytosis, leukocytapheresis (LA) could be considered as a bridge therapeutic option. Furthermore, sickle cell disease (SCD) in pregnant women is usually managed only with supportive care, i.e. packed red blood cell (RBC) transfusion to prevent excessive hemoglobin decrease, hydration and prevention of acute sickling crisis. Nevertheless, selected patients at high risk for placental detachment due to vasoocclusive acute crisis or with multiple pregnancies may benefit from prophylactic erythrocyte exchange (EEX). Both LA and EEX must be carried out by well trained personnel and the patients (and the fetus) must be under close clinical and instrumental monitoring. In the present paper, recent indications for performing either LA or EEX in pregnant patients are reviewed. PMID:26621538

  14. Nuclear abnormalities of marine fish erythrocytes.

    PubMed

    Strunjak-Perovic, I; Topic Popovic, N; Coz-Rakovac, R; Jadan, M

    2009-07-01

    The aim of this study was to monitor erythrocyte nuclear abnormalities (NA) including micronuclei (MN) in cultured and wild sea bass Dicentrarchus labrax and wild mullet Mugil spp. Seasonal sampling was performed at seven locations along the eastern coast of the Adriatic Sea. The frequency of NA and MN was positively correlated to temperature (NA: P < 0.05, r = 0.11; MN P < 0.05, r = 0.10), and there was also a positive correlation between NA and MN frequency (P < 0.001, r = 0.43). The lowest NA and MN values for both fish species were recorded in spring, while the highest were recorded in autumn. Significantly higher frequency of NA was seen in D. labrax compared to Mugil spp., while MN frequency was low in both species and not significantly different. There was no significant difference in NA and MN frequency between cultured and wild D. labrax sampled in the same month, and there was no difference between wild Mugil spp. sampled near or far from fish farms. In view of sampling sites, the highest values were detected in fishes from the Limski Channel, the lowest from the Janjina location.

  15. Energized endocytosis in human erythrocyte ghosts.

    PubMed Central

    Schriei, S L; Bensch, K G; Johnson, M; Junga, I

    1975-01-01

    The mechanism of endocytosis in resealed human erythrocyte ghosts was studied. The energy for endocytosis or micropinocytosis appears to be derived from Mg-ATP, and membrane internalization is preceded by activation of a membrane-associated Ca,Mg-ATPase and by the active efflux of Ca. Endocytosis, Ca,Mg-ATPase activity, and active Ca efflux all require the presence of Mg. Furthermore, these three phenomena, endocytosis, Ca,Mg-ATPase activity, and active Ca extrusion, all have a concentration dependence on Ca such that low concentrations stimulate and higher concentrations inhibit the phenomena. The optimal concentration of Ca is identical for endocytosis, active Ca efflux, and Ca,Mg-ATPase. Morphologic studies indicated that while active Ca efflux and activation of the Ca,Mg-ATPase activity occurred promptly upon onset of incubation, there was a significant time delay before endocytosis occurred, which suggests that endocytosis additionally involved a more slowly functioning mechanicochemical mechanism. Ruthenium red, a specific inhibitor of Ca,Mg-ATPase and Ca transport, inhibited endocytosis in a concentration-related manner. Prostaglandins E1 and E2 had no measurable effect on ghost endocytosis, active Ca efflux, or Ca,Mg-ATPase activity. Images PMID:124748

  16. Hemagglutinin-Neuraminidase Balance Influences the Virulence Phenotype of a Recombinant H5N3 Influenza A Virus Possessing a Polybasic HA0 Cleavage Site

    PubMed Central

    Diederich, Sandra; Berhane, Yohannes; Embury-Hyatt, Carissa; Hisanaga, Tamiko; Handel, Katherine; Cottam-Birt, Colleen; Ranadheera, Charlene; Kobasa, Darwyn

    2015-01-01

    ABSTRACT Although a polybasic HA0 cleavage site is considered the dominant virulence determinant for highly pathogenic avian influenza (HPAI) H5 and H7 viruses, naturally occurring virus isolates possessing a polybasic HA0 cleavage site have been identified that are low pathogenic in chickens. In this study, we generated a reassortant H5N3 virus that possessed the hemagglutinin (HA) gene from H5N1 HPAI A/swan/Germany/R65/2006 and the remaining gene segments from low pathogenic A/chicken/British Columbia/CN0006/2004 (H7N3). Despite possessing the HA0 cleavage site GERRRKKR/GLF, this rH5N3 virus exhibited a low pathogenic phenotype in chickens. Although rH5N3-inoculated birds replicated and shed virus and seroconverted, transmission to naive contacts did not occur. To determine whether this virus could evolve into a HPAI form, it underwent six serial passages in chickens. A progressive increase in virulence was observed with the virus from passage number six being highly transmissible. Whole-genome sequencing demonstrated the fixation of 12 nonsynonymous mutations involving all eight gene segments during passaging. One of these involved the catalytic site of the neuraminidase (NA; R293K) and is associated with decreased neuraminidase activity and resistance to oseltamivir. Although introducing the R293K mutation into the original low-pathogenicity rH5N3 increased its virulence, transmission to naive contact birds was inefficient, suggesting that one or more of the remaining changes that had accumulated in the passage number six virus also play an important role in transmissibility. Our findings show that the functional linkage and balance between HA and NA proteins contributes to expression of the HPAI phenotype. IMPORTANCE To date, the contribution that hemagglutinin-neuraminidase balance can have on the expression of a highly pathogenic avian influenza virus phenotype has not been thoroughly examined. Reassortment, which can result in new hemagglutinin

  17. Interaction of lectins with membrane receptors on erythrocyte surfaces.

    PubMed

    Sung, L A; Kabat, E A; Chien, S

    1985-08-01

    The interactions of human genotype AO erythrocytes (red blood cells) (RBCs) with N-acetylgalactosamine-reactive lectins isolated from Helix pomatia (HPA) and from Dolichos biflorus (DBA) were studied. Binding curves obtained with the use of tritium-labeled lectins showed that the maximal numbers of lectin molecules capable of binding to human genotype AO RBCs were 3.8 X 10(5) and 2.7 X 10(5) molecules/RBC for HPA and DBA, respectively. The binding of one type of lectin may influence the binding of another type. HPA was found to inhibit the binding of DBA, but not vice versa. The binding of HPA was weakly inhibited by a beta-D-galactose-reactive lectin isolated from Ricinus communis (designated RCA1). Limulus polyphemus lectin (LPA), with specificity for N-acetylneuraminic acid, did not influence the binding of HPA but enhanced the binding of DBA. About 80% of LPA receptors (N-acetylneuraminic acid) were removed from RBC surfaces by neuraminidase treatment. Neuraminidase treatment of RBCs resulted in increases of binding of both HPA and DBA, but through different mechanisms. An equal number (7.6 X 10(5) of new HPA sites were generated on genotypes AO and OO RBCs by neuraminidase treatment, and these new sites accounted for the enhancement (AO cells) and appearance (OO cells) of hemagglutinability by HPA. Neuraminidase treatment did not generate new DBA sites, but increased the DBA affinity for the existing receptors; as a result, genotype AO cells increased their hemagglutinability by DBA, while OO cells remained unagglutinable. The use of RBCs of different genotypes in binding assays with 3H-labeled lectins of known specificities provides an experimental system for studying cell-cell recognition and association.

  18. Mapping rare erythrocyte phenotypes in morocco: a tool to overcome transfusion challenges.

    PubMed

    Benahadi, A; Boulahdid, S; Adouani, B; Laouina, A; Mokhtari, A; Soulaymani, A; Hajjout, K; Benajiba, M; Alami, R

    2014-01-01

    The aim of this research is to search for the distribution of blood groups in all the regions of Morocco. This study, done for the first time, aimed to provide the frequency of the Rhesus system and Kell (K) in more than 55000 blood donors from nine different regions around the country. In addition, the frequency of the Cellano, Duffy, Kidd, and MNS blood antigens was searched for 500 blood donors from the Rabat's region. Frequency of blood donors with rare blood groups was characterized for the first time in the country and compared to results found from other populations. PMID:24744962

  19. The Cellular Localization of Human Cytomegalovirus Glycoprotein Expression Greatly Influences the Frequency and Functional Phenotype of Specific CD4+ T Cell Responses.

    PubMed

    Pachnio, Annette; Zuo, Jianmin; Ryan, Gordon B; Begum, Jusnara; Moss, Paul A H

    2015-10-15

    CMV infection is a significant cause of morbidity and mortality in immunocompromised individuals, and the development of a vaccine is of high priority. Glycoprotein B (gB) is a leading vaccine candidate but the glycoprotein H (gH) pentameric complex is now recognized as the major target for neutralizing Abs. However, little is known about the T cell immune response against gH and glycoprotein L (gL) and this is likely to be an important attribute for vaccine immunogenicity. In this study, we examine and contrast the magnitude and phenotype of the T cell immune response against gB, gH, and gL within healthy donors. gB-specific CD4(+) T cells were found in 95% of donors, and 29 epitopes were defined with gB-specific response sizes ranging from 0.02 to 2.88% of the CD4(+) T cell pool. In contrast, only 20% of donors exhibited a T cell response against gH or gL. Additionally, gB-specific CD4(+) T cells exhibited a more cytotoxic phenotype, with high levels of granzyme B expression. Glycoproteins were effectively presented following delivery to APCs but only gB-derived epitopes were presented following endogenous synthesis. gB expression was observed exclusively within vesicular structures colocalizing with HLA-DM whereas gH was distributed evenly throughout the cytoplasm. Grafting of the C-terminal domain from gB onto gH could not transfer this pattern of presentation. These results reveal that gB is a uniquely immunogenic CMV glycoprotein and this is likely to reflect its unique pattern of endogenous Ag presentation. Consideration may be required toward mechanisms that boost cellular immunity to gH and gL within future subunit vaccines.

  20. An iron stable isotope comparison between human erythrocytes and plasma.

    PubMed

    von Blanckenburg, Friedhelm; Oelze, Marcus; Schmid, Dietmar G; van Zuilen, Kirsten; Gschwind, Hans-Peter; Slade, Alan J; Stitah, Sylvie; Kaufmann, Daniel; Swart, Piet

    2014-11-01

    We present precise iron stable isotope ratios measured by multicollector-ICP mass spectrometry (MC-ICP-MS) of human red blood cells (erythrocytes) and blood plasma from 12 healthy male adults taken during a clinical study. The accurate determination of stable isotope ratios in plasma first required substantial method development work, as minor iron amounts in plasma had to be separated from a large organic matrix prior to mass-spectrometric analysis to avoid spectroscopic interferences and shifts in the mass spectrometer's mass-bias. The (56)Fe/(54)Fe ratio in erythrocytes, expressed as permil difference from the "IRMM-014" iron reference standard (δ(56/54)Fe), ranges from -3.1‰ to -2.2‰, a range typical for male Caucasian adults. The individual subject erythrocyte iron isotope composition can be regarded as uniform over the 21 days investigated, as variations (±0.059 to ±0.15‰) are mostly within the analytical precision of reference materials. In plasma, δ(56/54)Fe values measured in two different laboratories range from -3.0‰ to -2.0‰, and are on average 0.24‰ higher than those in erythrocytes. However, this difference is barely resolvable within one standard deviation of the differences (0.22‰). Taking into account the possible contamination due to hemolysis (iron concentrations are only 0.4 to 2 ppm in plasma compared to approx. 480 ppm in erythrocytes), we model the pure plasma δ(56/54)Fe to be on average 0.4‰ higher than that in erythrocytes. Hence, the plasma iron isotope signature lies between that of the liver and that of erythrocytes. This difference can be explained by redox processes involved during cycling of iron between transferrin and ferritin.

  1. Adenosine signaling in normal and sickle erythrocytes and beyond

    PubMed Central

    Zhang, Yujin; Xia, Yang

    2012-01-01

    Sickle cell disease (SCD) is a debilitating hemolytic genetic disorder with high morbidity and mortality affecting millions of individuals worldwide. Although SCD was discovered more than a century ago, no effective mechanism-based prevention and treatment are available due to poorly understood molecular basis of sickling, the fundamental pathogenic process of the disease. SCD patients constantly face hypoxia. One of the best-known signaling molecules to be induced under hypoxic conditions is adenosine. Recent studies demonstrate that hypoxia-mediated elevated adenosine signaling plays an important role in normal erythrocyte physiology. In contrast, elevated adenosine signaling contributes to sickling and multiple life threatening complications including tissue damage, pulmonary dysfunction and priapism. Here, we summarize recent research on the role of adenosine signaling in normal and sickle erythrocytes, progression of the disease and therapeutic implications. In normal erythrocytes, both genetic and pharmacological studies demonstrate that adenosine can enhance 2,3-bisphosphoglycerate (2,3-BPG) production via A2B receptor (ADORA2B) activation, suggesting that elevated adenosine has an unrecognized role in normal erythrocytes to promote O2 release and prevent acute ischemic tissue injury. However, in sickle erythrocytes, the beneficial role of excessive adenosine-mediated 2,3-BPG induction becomes detrimental by promoting deoxygenation, polymerization of sickle hemoglobin and subsequent sickling. Additionally, adenosine signaling via the A2A receptor (ADORA2A) on invariant natural killer T (iNKT) cells inhibits iNKT cell activation and attenuates pulmonary dysfunction in SCD mice. Finally, elevated adenosine coupled with ADORA2BR activation is responsible for priapism, a dangerous complication seen in SCD. Overall, the research reviewed here reveals a differential role of elevated adenosine in normal erythrocytes, sickle erythrocytes, iNK cells and progression

  2. Erythrocyte G Protein as a Novel Target for Malarial Chemotherapy

    PubMed Central

    Murphy, Sean C; Harrison, Travis; Hamm, Heidi E; Lomasney, Jon W; Mohandas, Narla; Haldar, Kasturi

    2006-01-01

    Background Malaria remains a serious health problem because resistance develops to all currently used drugs when their parasite targets mutate. Novel antimalarial drug targets are urgently needed to reduce global morbidity and mortality. Our prior results suggested that inhibiting erythrocyte Gs signaling blocked invasion by the human malaria parasite Plasmodium falciparum. Methods and Findings We investigated the erythrocyte guanine nucleotide regulatory protein Gs as a novel antimalarial target. Erythrocyte “ghosts” loaded with a Gs peptide designed to block Gs interaction with its receptors, were blocked in β-adrenergic agonist-induced signaling. This finding directly demonstrates that erythrocyte Gs is functional and that propranolol, an antagonist of G protein–coupled β-adrenergic receptors, dampens Gs activity in erythrocytes. We subsequently used the ghost system to directly link inhibition of host Gs to parasite entry. In addition, we discovered that ghosts loaded with the peptide were inhibited in intracellular parasite maturation. Propranolol also inhibited blood-stage parasite growth, as did other β2-antagonists. β-blocker growth inhibition appeared to be due to delay in the terminal schizont stage. When used in combination with existing antimalarials in cell culture, propranolol reduced the 50% and 90% inhibitory concentrations for existing drugs against P. falciparum by 5- to 10-fold and was also effective in reducing drug dose in animal models of infection. Conclusions Together these data establish that, in addition to invasion, erythrocyte G protein signaling is needed for intracellular parasite proliferation and thus may present a novel antimalarial target. The results provide proof of the concept that erythrocyte Gs antagonism offers a novel strategy to fight infection and that it has potential to be used to develop combination therapies with existing antimalarials. PMID:17194200

  3. The significance of erythrocyte antigen site density

    PubMed Central

    Hoyer, Leon W.; Trabold, Norma C.

    1971-01-01

    The importance of antigen site density has been studied by means of a model passive hemolysis system using red cells coupled with sulfanilic acid groups. Relative site numbers were estimated from the covalent linkage of sulfanilic acid-35S to red cell membrane protein, and the effective antigen site number was determined with 125I-labeled rabbit IgG anti-sulfanilic acid (anti-S). Immune hemolysis was demonstrated for red cells which had greater than a threshold number of antigen sites, the value of which was different for normal human cells (80,000 sites/cell), cells from a patient with paroxysmal nocturnal hemoglobinuria (PNH) (40,000 sites/cell), and sheep red blood cells (RBC) (15,000 sites/cell). Cells with antigen site densities below these values did not hemolyze when tested with 1 mg/ml purified rabbit IgM anti-S. 2-8 times greater antigen site densities were required to obtain hemolysis with IgG anti-S. Above the threshold value, hemolysis titers were proportional to the antigen site number until maximal values were obtained. The greater hemolytic efficiency of IgM antibody was demonstrated in this system, and it was established that the magnitude of the difference was related to the test cell antigen site density. These data, taken with previously reported hemagglutination studies, have been used to develop a general classification of immune hemolysis and hemagglutination based on antigen site density and antibody class. It is suggested that the heterogeneity of blood group systems is caused by differences in the site separation of erythrocyte membrane antigens. PMID:5105661

  4. Meta-analysis of the influence of TM6SF2 E167K variant on Plasma Concentration of Aminotransferases across different Populations and Diverse Liver Phenotypes

    PubMed Central

    Sookoian, Silvia; Pirola, Carlos J.

    2016-01-01

    A nonsynonymous E167K (rs58542926 C/T) variant in TM6SF2 gene was recently associated with nonalcoholic fatty liver disease (NAFLD). We explored the association between E167K and plasma concentrations of alanine (ALT) and aspartate (AST) aminotransferases through a meta-analysis. We also estimated the strength of the effect across diverse liver phenotypes, including NAFLD and chronic viral hepatitis; fourteen studies were included. We found that ALT (p = 3.2 × 10−6, n = 94,414) and AST (p = 0007, n = 93,809) levels were significantly associated with rs58542926 in NAFLD. By contrast, rs58542926 was not associated with either ALT (p = 0.24, n = 4187) or AST (p = 0.17, n = 2678) levels in four studies on chronic hepatitis. In conclusion, the results of the pooled estimates in patients with NAFLD showed that carriers of the T allele (EK + KK), when compared with homozygous subjects for the C allele (EE genotype) have increased levels of aminotransferases; however, this increase represents –2.5 (9.8%) and 1.2 (5%) IU/L of ALT and AST respectively, which is fairly small compared with the large effect of PNPLA3- rs738409-G allele that is associated with a –28% increase in serum ALT. PMID:27278285

  5. Hatching behavior of eastern long-necked turtles (Chelodina longicollis): The influence of asynchronous environments on embryonic heart rate and phenotype.

    PubMed

    McGlashan, Jessica K; Loudon, Fiona K; Thompson, Michael B; Spencer, Ricky-John

    2015-10-01

    Variable temperatures within a nest cause asynchronous development within clutches of freshwater turtle embryos, yet synchronous hatching occurs and is thought to be an important survival strategy for hatchlings. Metabolic compensation and circadian rhythms in heart rates of embryonic turtles indicate the potential of communication between embryos in a nest. Heart rates were used to identify metabolic circadian rhythms in clutches of an Australian freshwater turtle (Chelodina longicollis) and determine whether embryos metabolically compensate and hatch synchronously when incubated in asynchronous environments. The effects of a group environment during incubation on egg development and incubation period were also investigated during the final 3 weeks of development. Chelodina longicollis hatch synchronously and metabolically compensate so that less advanced embryos catch up to more advanced clutch-mates. Heart rates of embryos remained stable from week 4-7 in asynchronous (M=89 bpm) and synchronous (M=92 bpm) groups and declined in the final 2 weeks of incubation (M=72 and 77 bpm). Circadian rhythms were present throughout development and diel heart rates of embryos in asynchronous groups showed less deviation from the mean (M=-0.5 bpm) than synchronous groups (M=-4 bpm). Eggs incubated in groups had a significantly shorter incubation period than eggs incubated individually. Phenotypic traits including size, performance, and growth of all hatchlings were not affected. Egg position within a turtle nest is important for coordinating development throughout incubation and facilitating synchronous hatching.

  6. Hatching behavior of eastern long-necked turtles (Chelodina longicollis): The influence of asynchronous environments on embryonic heart rate and phenotype.

    PubMed

    McGlashan, Jessica K; Loudon, Fiona K; Thompson, Michael B; Spencer, Ricky-John

    2015-10-01

    Variable temperatures within a nest cause asynchronous development within clutches of freshwater turtle embryos, yet synchronous hatching occurs and is thought to be an important survival strategy for hatchlings. Metabolic compensation and circadian rhythms in heart rates of embryonic turtles indicate the potential of communication between embryos in a nest. Heart rates were used to identify metabolic circadian rhythms in clutches of an Australian freshwater turtle (Chelodina longicollis) and determine whether embryos metabolically compensate and hatch synchronously when incubated in asynchronous environments. The effects of a group environment during incubation on egg development and incubation period were also investigated during the final 3 weeks of development. Chelodina longicollis hatch synchronously and metabolically compensate so that less advanced embryos catch up to more advanced clutch-mates. Heart rates of embryos remained stable from week 4-7 in asynchronous (M=89 bpm) and synchronous (M=92 bpm) groups and declined in the final 2 weeks of incubation (M=72 and 77 bpm). Circadian rhythms were present throughout development and diel heart rates of embryos in asynchronous groups showed less deviation from the mean (M=-0.5 bpm) than synchronous groups (M=-4 bpm). Eggs incubated in groups had a significantly shorter incubation period than eggs incubated individually. Phenotypic traits including size, performance, and growth of all hatchlings were not affected. Egg position within a turtle nest is important for coordinating development throughout incubation and facilitating synchronous hatching. PMID:26119599

  7. Origins and function of 3-ribosylurate in bovid erythrocytes.

    PubMed

    Davids, V; Blackhurst, D M; Katz, A A; Harley, E H

    2012-06-01

    3-Ribosylurate is a dominant feature on high performance liquid chromatography (HPLC) profiles of acid extracts of erythrocytes from cows and buffalo, but is HPLC-undetectable in acid extracts of erythrocytes from all other species examined to date. Various aspects of this unique low molecular weight substance remain unexplored since it was first identified. In this study, the mutation(s) responsible for the appearance of ribosylurate in these cells is shown to be specific to members of both tribes of the Bovinae subfamily (Bovidae family), being detectable in the erythrocytes of both the cow and the buffalo (Bovini tribe) as well as in the kudu (Strepsicerotini tribe), but not in representative species from the other subfamilies of the Bovidae family. More specifically, expression of the mutation(s) seems to be restricted to the erythrocyte lineage of these species, ribosylurate being undetectable in cow white blood cells and primary cultures of fibroblasts. Novel evidence is presented that ribosylurate has antioxidant activity. Accumulation of high levels specifically within the haemoglobin-rich milieu of circulating erythrocytes may serve to protect perfused tissues by removing pathophysiological levels of hydrogen peroxide from plasma. Maintenance of ribosylurate levels may be important in conditions associated with oxidative stress in Bovinae.

  8. Biochemistry of the erythrocyte Rh polypeptides: a review.

    PubMed Central

    Agre, P.; Smith, B. L.; Hartel-Schenk, S.

    1990-01-01

    The clinically important Rh blood group system is complex, consisting of multiple distinct antigens. Despite clinical recognition for over 50 years, the Rh blood group antigens have remained poorly understood on a molecular level until the recent identification and characterization of the "Rh polypeptides," the core structural proteins of the Rh antigens. This group of erythrocyte membrane proteins of molecular weight 30,000-35,000 daltons was first recognized by employing Rh-specific antibodies to immunoprecipitate radiolabeled components of erythrocyte membranes. By using antibodies specific for the Rh D, c, and E antigens, a series of highly related non-identical proteins were immunoprecipitated, indicating that the Rh antigens are composed of multiple related proteins. The Rh polypeptides have been purified and characterized, and they were found to have several unusual biochemical characteristics. The Rh polypeptides penetrate the membrane bilayer; they are linked to the underlying membrane skeleton; they are covalently fatty acid acylated with palmitate. While the Rh antigenic reactivity is unique to human erythrocytes, the Rh polypeptides have been isolated from erythrocytes of diverse species and are thought to be fundamental components of all mammalian erythrocyte membranes. The functional role of the Rh polypeptides remains undefined, but a role in the organization of membrane phospholipid is suspected. PMID:2127333

  9. Developmental patterns of antioxidant defense mechanisms in human erythrocytes.

    PubMed

    Ripalda, M J; Rudolph, N; Wong, S L

    1989-10-01

    To obtain a profile of erythrocyte antioxidant defense potential during late fetal development, we studied selected antioxidant parameters in blood samples from 65 neonates with birth wt between 520 and 4210 g and from 12 healthy adults. Erythrocyte superoxide dismutase activity did not change significantly with maturation and no significant differences were observed among preterm infants grouped in increasing birth wt categories, term neonates, and adults. Erythrocyte catalase and glutathione peroxidase, as well as plasma vitamin E levels, showed highly significant positive correlations (p less than 0.001) with increasing fetal wt and gestational age; by term, CAT activity reached a level similar to the adult control group, but glutathione peroxidase activity, as well as plasma vitamin E levels, were markedly lower in all the preterm and in the term groups than in adults (p less than 0.01). Erythrocyte glutathione S-transferase activity showed a negative correlation with increasing gestational age (p less than 0.01) and the adult values were considerably lower than any of the neonatal levels (p less than 0.001). The role of glutathione S-transferase in erythrocyte metabolism remains obscure. Maturational changes in the activity of the red cell enzymes that were studied and in the plasma vitamin E level were apparent from about 31-36 wk of gestation, suggesting that the stimulation for these changes may have commenced from about 28-31 wk.

  10. Effects of the antiepileptic drug carbamazepine on human erythrocytes.

    PubMed

    Suwalsky, Mario; Mennickent, Sigrid; Norris, Beryl; Villena, Fernando; Sotomayor, Carlos P

    2006-12-01

    The structural effects of the antiepileptic drug carbamazepine (CBZ) on the human erythrocyte membrane and molecular models have been investigated in the present work. This report presents the following evidence that CBZ interacts with red cell membranes: (a) X-ray diffraction and fluorescence spectroscopy of phospholipid bilayers showed that CBZ perturbed a class of lipids found in the outer moiety of the erythrocyte membrane; (b) in isolated unsealed human erythrocytes (IUM) the drug induced a disordering effect on the polar head groups and acyl chains of the membrane lipid bilayer; (c) in scanning electron microscopy (SEM) studies on human erythrocytes the formation of echinocytes was observed, due to the preferential insertion of CBZ in the outer monolayer of the red cell membrane. The effects of the drug detected in the present work were observed at concentrations of the order of those currently appearing in serum when it is therapeutically administered. This is the first time that toxic effects of carbamazepine on the human erythrocyte membrane have been described. PMID:16844339

  11. Disorders of erythrocyte structure and function in hypertensive patients

    PubMed Central

    Pytel, Edyta; Duchnowicz, Piotr; Jackowska, Paulina; Wojdan, Katarzyna; Koter-Michalak, Maria; Broncel, Marlena

    2012-01-01

    Summary Background The prevalence of hypertension is growing at an alarming rate. Increasing attention is being focussed on the oxidative stress accompanying this disease. In this study we examined the impact of this disease on some parameters of erythrocytes and human blood plasma. Material/Methods We examined the impact of hypertension on some parameters of erythrocytes and human plasma. The study involved 13 patients with hypertension and 19 healthy subjects. We determined lipid peroxidation, SH groups concentration, antioxidants enzymes activity, ATPase activity, total antioxidant capacity, total cholesterol level and erythrocyte membrane fluidity. Results We found an increased level of lipid peroxidation and the concentration of SH groups in membrane proteins in patients with hypertension, and a decrease in the activity of catalase and superoxide dysmutase. No changes were observed in glutathione peroxidase and ATPase activity, level of total antioxidant capacity, total cholesterol level and fluidity of erythrocyte membranes. Conclusions These results suggest the existence of an impaired oxidative balance in hypertensive human erythrocytes. PMID:22847194

  12. Substrate specificity of amino acid transport in sheep erythrocytes.

    PubMed Central

    Young, J D; Ellory, J C

    1977-01-01

    The specificity of amino acid transport in normal (high-glutathione) sheep erythrocytes was investigated by studying the interaction of various neutral and dibasic amino acids in both competition and exchange experiments. Apparent Ki values were obtained for amino acids as inhibitors of L-alanine influx. Amino acids previously found to be transported by high-glutathione cells at fast rates (L-cysteine, L-alpha-amino-n-butyrate) were the most effective inhibitors. D-Alanine and D-alpha-amino-n-butyrate were without effect. Of the remaining amino acids studied, only L-norvaline, L-valine, L-norleucine, L-serine and L-2,4-diamino-n-butyrate significantly inhibited L-alanine uptake. L-Alanine efflux from pre-loaded cells was markedly stimulated by extracellular L-alanine. Those amino acids that inhibited L-alanine influx also stimulated L-alanine efflux. In addition, D-alanine, D-alpha-amino-n-biutyrate, L-threonine, L-asparagine, L-alpha, beta-diaminoproprionate, L-ornithine, L-lysine and S-2-aminoethyl-L-cysteine also significantly stimulated L-alanine efflux. L-Lysine uptake was inhibited by L-alanine but not by D-alanine, and the inhibitory potency of L-alanine was not influenced by the replacement of Na+ in the incubation medium with choline. L-Lysine efflux from pre-loaded cells was stimulated by L-alanine but not by D-alanine. It is concluded that these cells possess a highly selective stero-specific amino acid-transport system. Although the optimum substrates are small neutral amino acids, this system also has a significant affinity for dibasic amino acids. PMID:849280

  13. Clinical Factors Influencing Phenotype of HCMV-Specific CD8+ T Cells and HCMV-Induced Interferon-Gamma Production after Allogeneic Stem Cells Transplantation

    PubMed Central

    Cantisán, Sara; Cerrato, Carolina; Sánchez-García, Joaquín; Martin, Carmen; Solana, Rafael; Torres-Gomez, Antonio; Torre-Cisneros, Julian

    2013-01-01

    Human cytomegalovirus (HCMV) infection causes significant morbidity and mortality after hematopoietic stem cell transplantation (HSCT). In this work, we characterized the phenotype and interferon-gamma (INF-γ) production of HCMV-specific T cells using QuantiFERON-HCMV assay in 26 patients 6 months after HSCT. We analysed whether these two parameters were associated with clinical variables. Our results showed that the patients receiving stem cells from donors ≥40 years old were 12 times more likely to have HCMV-specific CD8+ T cells with “differentiated phenotype” (CD45RA+CCR7+ ≤6.7% and CD28+ ≤30%) than patients grafted from donors <40 years old (OR = 12; P = 0.014). In addition, a detectable IFN-γ production in response to HCMV peptides (cutoff 0.2 IU/mL IFN-γ; “reactive” QuantiFERON-HCMV test) was statistically associated with HCMV replication after transplantation (OR = 11; P = 0.026), recipients ≥40 versus <40 years old (OR = 11; P = 0.026), and the use of peripheral blood versus bone marrow as stem cell source (OR = 17.5; P = 0.024). In conclusion, donor age is the only factor significantly associated with the presence of the “differentiated phenotype” in HCMV-specific CD8+ T cells, whereas HCMV replication after transplantation, recipient age, and stem cell source are the factors associated with the production of IFN-γ in response to HCMV epitopes. PMID:23424600

  14. [Effects of La3+ on calcium binding to erythrocyte cytoskeleton].

    PubMed

    Kravtsov, G M; Postnov, Iu V

    1992-02-01

    When the whole erythrocytes were exposed to LaCl3, A--23187, ionomycin, orthovanadate and saponin, there was Ca2+ binding only following La3+ treatment of the cells. The binding was evident at a wide range (0.1 microM--1.OmM) of La3+ concentrations. Iodoacetamide-induced (incubation for 3 hours, 37 degrees C) decrease in erythrocyte ATP levels was found to result in a 3-fold reduction in Ca2+ binding to the cytoskeleton. La(3+)-induced Ca2+ binding enhanced the incorporation of 14C-glucose and/or its metabolites into the red cell skeleton. Thus, the detected new type of Ca2+ binding to the cytoskeleton of human and rat erythrocytes is likely to be due to the cumulative process: direct binding of La3+ to the outer surface of a membrane and the metal-induced trigger of nucleotide--dependent intracellular process.

  15. Optical Assay of Erythrocyte Function in Banked Blood

    PubMed Central

    Bhaduri, Basanta; Kandel, Mikhail; Brugnara, Carlo; Tangella, Krishna; Popescu, Gabriel

    2014-01-01

    Stored red blood cells undergo numerous biochemical, structural, and functional changes, commonly referred to as storage lesion. How much these changes impede the ability of erythrocytes to perform their function and, as result, impact clinical outcomes in transfusion patients is unknown. In this study we investigate the effect of the storage on the erythrocyte membrane deformability and morphology. Using optical interferometry we imaged red blood cell (RBC) topography with nanometer sensitivity. Our time-lapse imaging quantifies membrane fluctuations at the nanometer scale, which in turn report on cell stiffness. This property directly impacts the cell's ability to transport oxygen in microvasculature. Interestingly, we found that cells which apparently maintain their normal shape (discocyte) throughout the storage period, stiffen progressively with storage time. By contrast, static parameters, such as mean cell hemoglobin content and morphology do not change during the same period. We propose that our method can be used as an effective assay for monitoring erythrocyte functionality during storage time. PMID:25189281

  16. Frequency of enzyme deficiency variants in erythrocytes of newborn infants

    SciTech Connect

    Mohrenweiser, H.W.

    1981-08-01

    The frequency of enzyme deficiency variants, defined as alleles whose products are either absent or almost devoid of normal activity in erythrocytes, was determined for nine erythrocyte enzymes in some 675 newborn infants and in approximately 200 adults. Examples of this type of genetic abnormality, which in the homozygous condition are often associated with significant health consequences, were detected for seven of the nine enzymes studied. Fifteen inherited enzyme deficiency variants in 1809 determinations from adults were identified. Seven of the deficiency variants involved triosephosphate isomerase, a frequency of 0.01 in the newborn population. The average frequency of 2.4/1000 is 2 to 3 times the frequency observed for rare electrophoretic variants of erythrocyte enzymes in this same population.

  17. Determination of somatic mutations in human erythrocytes by cytometry

    SciTech Connect

    Jensen, R.H.; Langlois, R.G.; Bigbee, W.L.

    1985-06-21

    Flow cytometric assays of human erythrocytes labeled with monoclonal antibodies specific for glycophorin A were used to enumerate variant cells that appear in peripheral blood as a result of somatic gene-loss mutations in erythrocyte precursor cells. The assay was performed on erythrocytes from 10 oncology patients who had received at least one treatment from radiation or mutagenic chemotherapy at least 3 weeks before being assayed. The patients were suffering from many different malignancies (e.g., breast, renal, bone, colon and lung), and were treated with several different mutagenic therapeutics (e.g., cisplatinum, adriamycin, daunomycin, or cyclophosphamide). The frequency of these variant cells is an indication of the amount of mutagenic damage accumulated in the individual's erythropoietic cell population. Comparing these results to HPRT clonogenic assays, we find similar baseline frequencies of somatic mutation as well as similar correlation with mutagenic exposures. 9 refs., 3 figs., 1 tab.

  18. Specific binding of beta-endorphin to normal human erythrocytes

    SciTech Connect

    Chenet, B.; Hollis, V. Jr.; Kang, Y.; Simpkins, C.

    1986-03-05

    Beta-endorphin (BE) exhibits peripheral functions which may not be mediated by interactions with receptors in the brain. Recent studies have demonstrated binding of BE to both opioid and non-opioid receptors on lymphocytes and monocytes. Abood has reported specific binding of /sup 3/H-dihydromorphine in erythrocytes. Using 5 x 10/sup -11/M /sup 125/I-beta-endorphin and 10/sup -5/M unlabeled BE, they have detected 50% specific binding to human erythrocytes. This finding is supported by results from immunoelectron microscopy using rabbit anti-BE antibody and biotinylated secondary antibody with avidin-biotin complexes horseradish peroxidase. Binding is clearly observed and is confined to only one side of the cells. Conclusions: (1) BE binding to human erythrocytes was demonstrated by radioreceptor assay and immunoelectron microscopy, and (2) BE binding sites exist on only one side of the cells.

  19. [Structural-functional changes in erythrocyte membranes in bovine lympholeukemia].

    PubMed

    Riazantsev, V V; Kovalenko, L V; Belous, A M

    1996-01-01

    The condition of lipid peroxidation and activity of enzymes of protective glutathione-dependent anti-oxidation system of erythrocytes: glutathione peroxidase (GSH-P) and glutathione reductase (GSH-R) in cows with leukosis has been studied. The decrease of the level of MDA and GSH-R activity was accompanied by GSH-P activation depending on the stage disease. The considerable lowering of Ca2+ transport to erythrocytes was shown on hematological stage of leucosis. The qualitative composition of membrane proteins does not change according to gel electrophoresis data. But the quantity of main cytoskeleton protein, spectrin, increases in the "white shadows" of erythrocytes in the animals with leucosis. PMID:8755110

  20. Effect of osmotic pressure to bioimpedance indexes of erythrocyte suspensions

    NASA Astrophysics Data System (ADS)

    Melnikov, A. A.; Nikolaev, D. V.; Malahov, M. V.; Smirnov, A. V.

    2012-12-01

    In the paper we studied effects of osmotic modification of red blood cells on bioimpedance parameters of erythrocyte suspension. The Cole parameters: the extracellular (Re) and intracellular (Ri) fluid resistance, the Alpha parameter, the characteristic frequency (Fchar) and the cell membranes capacitance (Cm) of concentrated erythrocyte suspensions were measured by bioimpedance analyser in the frequency range 5 - 500 kHz. Erythrocytes were incubated in hypo-, hyper- and isoosmotic solutions to achieve changes in cell volume. It was found that Re and Alpha increased in the suspensions with low osmolarity and decreased in the hypertonic suspensions. Ri, Fchar and Cm were higher in the hyperosmotic and were lower in the hypoosmotic suspensions. Correlations of all BIS parameters with MCV were obtained, but multiple regression analysis showed that only Alpha parameter was independently related to MCV (β=0.77, p=0.01). Thus Alpha parameter may be related the mean corpuscular volume of cells.

  1. Optical Assay of Erythrocyte Function in Banked Blood

    NASA Astrophysics Data System (ADS)

    Bhaduri, Basanta; Kandel, Mikhail; Brugnara, Carlo; Tangella, Krishna; Popescu, Gabriel

    2014-09-01

    Stored red blood cells undergo numerous biochemical, structural, and functional changes, commonly referred to as storage lesion. How much these changes impede the ability of erythrocytes to perform their function and, as result, impact clinical outcomes in transfusion patients is unknown. In this study we investigate the effect of the storage on the erythrocyte membrane deformability and morphology. Using optical interferometry we imaged red blood cell (RBC) topography with nanometer sensitivity. Our time-lapse imaging quantifies membrane fluctuations at the nanometer scale, which in turn report on cell stiffness. This property directly impacts the cell's ability to transport oxygen in microvasculature. Interestingly, we found that cells which apparently maintain their normal shape (discocyte) throughout the storage period, stiffen progressively with storage time. By contrast, static parameters, such as mean cell hemoglobin content and morphology do not change during the same period. We propose that our method can be used as an effective assay for monitoring erythrocyte functionality during storage time.

  2. Simulation of dielectric spectra of erythrocytes with various shapes

    NASA Astrophysics Data System (ADS)

    Asami, Koji

    2009-07-01

    Dielectric spectra of erythrocyte suspensions were numerically simulated over a frequency range from 1 kHz to 100 MHz to study the effects of erythrocyte shape on the dielectric spectra. First, a biconcave-discoid model for normal erythrocytes or discocytes was compared with an equivalent oblate spheroid model. The two models showed similar dielectric spectra to each other, suggesting that the oblate spheroid model can be approximately used for discocytes. Second, dielectric spectra were simulated for discocytes deformed by osmotic cell swelling. The deformation resulted in the increase in relaxation intensity and the sharpening of spectrum shape. Finally, dielectric spectra were simulated for echinocytes, stomatocytes and sickle cells that are induced by chemical agents and diseases. The dielectric spectra of echinocytes and stomatocytes were similar to each other, being distinguishable from that of discocytes and quite different from that of sickle cells.

  3. The interactions of fibrinogen and dextrans with erythrocytes

    PubMed Central

    Rampling, M.; Sirs, John A.

    1972-01-01

    1. The rate of packing of erythrocytes in whole blood, under a centrifugal field of 200 g, has been studied using an automatic recording centrifuge. 2. Reduction of the supernatant fibrinogen concentration, by repeatedly washing the cells, lowers the rate of packing and reduces the cell flexibility. 3. Resuspending the cells in their own plasma or in isotonic solutions containing fibrinogen restores their flexibility. 4. Rouleaux formation has been shown to have no effect on the rate of packing by comparison of blood diluted with plasma, isotonic NaCl or Ringer—Locke solutions. While the degree of rouleaux formation varied with the diluent used, the rate of packing and packed cell haematocrit were the same, for the same dilution. 5. Both formalin and dextran altered the degree of rouleaux formation and reduced erythrocyte flexibility. Dextran was found to act indirectly on the erythrocyte flexibility by reducing the plasma fibrinogen concentration. PMID:5046146

  4. Comparison of three optical methods to study erythrocyte aggregation.

    PubMed

    Zhao, H; Wang, X; Stoltz, J F

    1999-01-01

    The aim of this work was to evaluate three optical methods designed to determine erythrocyte aggregation: Erythroaggregometer (EA; Regulest, France), Laser-assisted Optical Rotational Cell Analyzer (LORCA; Mechatronics, Netherlands) and Fully Automatic Erythrocyte Aggregometer (FAEA; Myrenne, GmbH, Germany). Blood samples were taken from fifty donors (26 males and 24 females). The aggregation of normal red blood cell (RBC) and RBCs suspended in three normo- and hyperaggregating suspending media was studied. The results revealed some significant correlations between parameters measured by these instruments, in particular, between the indexes of aggregation of EA and LORCA. Further, RBC aggregation of multiple myeloma patients was also studied and a hyper erythrocyte aggregation state was found by EA and LORCA.

  5. Stress-induced rigidification of erythrocytes as determined by laser diffraction and image analysis

    NASA Astrophysics Data System (ADS)

    Wolf, Guido; Bayer, Rainer; Ostuni, Dieter

    1992-07-01

    An apparatus to measure red cell deformability, the laser diffractoscope, is presented. As in ektacytometry, the apparatus generates diffraction patterns using a laser beam that passes through a red blood cell (RBC) suspension in a viscometer. Introducing a CCD camera to record the diffraction pattern and computer-aided image analysis has reduce the measurement error to below 1% (variation coefficient). Employing this apparatus we have studied the effects of mechanical stress on RBC deformability in vitro. We submitted the erythrocytes to different shear stresses of various magnitudes (260 to 2620/s, viscosity of suspending medium 24 cP) and variable duration 1 to 16 min). We demonstrate that a high mechanical stress reduces deformability at low shear rates but does not influence elongation at high shear rates and that the rigidification is related to mechanical stress in a dose-dependent manner. The period of exposure as well as the degree of mechanical stress influences the extent of deformability loss. We also show that RBC rigidification accumulates if mechanical stress is applied repetitively, the cells could not recover from this stress, below a certain threshold (1100/s, 24 cP) shearing does not produce any loss of flexibility, and the decrease of deformability is not accompanied with detectable hemolysis. It is suggested that the shear- induced rigidification is due to rearrangements in the cytoskeleton of the erythrocyte.

  6. Rat Erythrocyte Insulin Receptors: Radioreceptor Assay and Characterization

    PubMed Central

    Ogunwole, John O.; Nerurkar, Shriniwas G.; Hollis, Vincent W.

    1985-01-01

    Highly specific insulin receptors have been identified on the rat erythrocyte. A radioreceptor assay for the evaluation of these receptors has been developed, and the characteristics of these receptors have been investigated. Insulin receptor binding on the rat erythrocytes was found to be dependent on pH, temperature, time, and ionic strength. When incubated for 3½ hours at 15° C, 5.0 × 109 erythrocytes/mL from each of 10 rats were found to bind specifically 7.54 percent (±0.15 SEM) of 40 pg of 125I-insulin. Specific binding was found to be a function of cell concentration. The pH optima for insulin binding were found to be 7.4 and 7.0 in the absence of cations. The presence of cations not only shifted pH optimum to 7.4 from 7.0, but also increased specific insulin binding. These observations suggest the stabilization of negatively charged groups on ligand and receptor, as well as providing a suitable ionic environment for the hormone-receptor interaction. Based on the resistance of rat erythrocytes to the pH of the external buffer, a simple method for determining the internal pH of rat red- blood cells is described. Scatchard analyses of insulin-binding data yielded curvilinear plots, and the number of receptor sites per cell was found to be 762 (±12.1 SD), as opposed to the large variation (410 ± 260 SD) in normal humans. The rat erythrocytes may serve as a useful, precise, sensitive, and efficient model system for future erythrocytic-receptor studies that would be difficult to obtain from human subjects. PMID:3981646

  7. Rat erythrocyte insulin receptors: radioreceptor assay and characterization.

    PubMed

    Ogunwole, J O; Nerurkar, S G; Hollis, V W

    1985-02-01

    Highly specific insulin receptors have been identified on the rat erythrocyte. A radioreceptor assay for the evaluation of these receptors has been developed, and the characteristics of these receptors have been investigated. Insulin receptor binding on the rat erythrocytes was found to be dependent on pH, temperature, time, and ionic strength. When incubated for 3½ hours at 15° C, 5.0 × 10(9) erythrocytes/mL from each of 10 rats were found to bind specifically 7.54 percent (±0.15 SEM) of 40 pg of (125)I-insulin. Specific binding was found to be a function of cell concentration. The pH optima for insulin binding were found to be 7.4 and 7.0 in the absence of cations. The presence of cations not only shifted pH optimum to 7.4 from 7.0, but also increased specific insulin binding.These observations suggest the stabilization of negatively charged groups on ligand and receptor, as well as providing a suitable ionic environment for the hormone-receptor interaction. Based on the resistance of rat erythrocytes to the pH of the external buffer, a simple method for determining the internal pH of rat red- blood cells is described. Scatchard analyses of insulin-binding data yielded curvilinear plots, and the number of receptor sites per cell was found to be 762 (±12.1 SD), as opposed to the large variation (410 ± 260 SD) in normal humans. The rat erythrocytes may serve as a useful, precise, sensitive, and efficient model system for future erythrocytic-receptor studies that would be difficult to obtain from human subjects.

  8. Erythrocyte stiffness during morphological remodeling induced by carbon ion radiation.

    PubMed

    Zhang, Baoping; Liu, Bin; Zhang, Hong; Wang, Jizeng

    2014-01-01

    The adverse effect induced by carbon ion radiation (CIR) is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy) or X-rays (2, 4, 6, and 12 Gy) for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy). The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study provides a new

  9. Erythrocyte Stiffness during Morphological Remodeling Induced by Carbon Ion Radiation

    PubMed Central

    Zhang, Baoping; Liu, Bin; Zhang, Hong; Wang, Jizeng

    2014-01-01

    The adverse effect induced by carbon ion radiation (CIR) is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy) or X-rays (2, 4, 6, and 12 Gy) for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy). The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study provides a new

  10. Role of erythrocytes in leukocyte-endothelial interactions: mathematical model and experimental validation.

    PubMed Central

    Munn, L L; Melder, R J; Jain, R K

    1996-01-01

    The binding of circulating cells to the vascular wall is a central process in inflammation, metastasis, and therapeutic cell delivery. Previous in vitro studies have identified the adhesion molecules on various circulating cells and the endothelium that govern the process under static conditions. Other studies have attempted to simulate in vivo conditions by subjecting adherent cells to shear stress as they interact with the endothelial cells in vitro. These experiments are generally performed with the cells suspended in Newtonian solutions. However, in vivo conditions are more complex because of the non-Newtonian flow of blood, which is a suspension consisting of 20-40% erythrocytes by volume. The forces imparted by the erythrocytes in the flow can contribute to the process of cell adhesion. A number of experimental and theoretical studies have suggested that the rheology of blood can influence the binding of circulating leukocytes by increasing the normal and axial forces on leukocytes or the frequency of their collision with the vessel wall, but there have been no systematic investigations of these phenomena to date. The present study quantifies the contribution of red blood cells (RBCs) in cell capture and adhesion to endothelial monolayers using a combination of mathematical modeling and in vitro studies. Mathematical modeling of the flow experiments suggested a physical mechanism involving RBC-induced leukocyte dispersion and/or increased normal adhesive contact. Flow chamber studies performed with and without RBCs in the suspending medium showed increases in wall collision and binding frequencies, and a decrease in rolling velocity in the presence of erythrocytes. Increased fluid viscosity alone did not influence the binding frequency, and the differences could not be attributed to large near-wall excesses of the lymphocytes. The results indicate that RBCs aid in the transport and initial engagement of lymphocytes to the vascular wall, modifying the existing

  11. Characterization of N-acyl homoserine lactones (AHLs) producing bacteria isolated from vacuum-packaged refrigerated turbot (Scophthalmus maximus) and possible influence of exogenous AHLs on bacterial phenotype.

    PubMed

    Zhang, Caili; Zhu, Suqin; Jatt, Abdul-Nabi; Zeng, Mingyong

    2016-01-01

    Quorum sensing (QS) is a cell-to-cell communication mechanism through which microbial cells communicate and regulate their wide variety of biological activities. N-acyl homoserine lactones (AHLs) are considered to be the most important QS signaling molecules produced by several Gram-negative bacteria. The present study aimed to screen the AHLs-producing bacteria from spoiled vacuum-packaged refrigerated turbot (Scophthalmus maximus) by biosensor assays, and the profiles of AHLs produced by these bacteria were determined using reversed-phase thin-layer chromatography (RP-TLC) and gas chromatography-mass spectrometry (GC-MS). Effects of exogenous AHLs and QS inhibitor (QSI) on the phenotypes (i.e., extracellular proteolytic activity and biofilm formation) of the AHLs-producing bacteria were also evaluated. Our results demonstrated that eight out of twenty-two isolates were found to produce AHLs. Three of the AHLs-producing isolates were identified as Serratia sp., and the other five were found to belong to the family of Aeromonas. Two isolates (i.e., S. liquefaciens A2 and A. sobria B1) with higher AHLs-producing activities were selected for further studies. Mainly, RP-TLC and GC-MS analysis revealed three AHLs, i.e., 3-oxo-C6-HSL, C8-HSL and C10-HSL were produced by S. liquefaciens A2, while five AHLs, i.e., C4-HSL, C6-HSL, C8-HSL, C10-HSL, and C12-HSL, were produced by A. sobria B1. Moreover, production of AHLs in both bacterial strains were found to be density-dependent, and the AHLs activity reached a maximum level in their middle logarithmic phase and decreased in the stationary phase. The addition of exogenous AHLs and QSI decreased the specific protease activity both of the Serratia A2 and Aeromonas B1. Exogenous AHLs inhibited the biofilm formation of Serratia A2 while it enhanced the biofilm formation in Aeromonas B1. QSI inhibited the specific protease activity and biofilm formation in both bacterial strains. PMID:27118073

  12. Characterization of N-acyl homoserine lactones (AHLs) producing bacteria isolated from vacuum-packaged refrigerated turbot (Scophthalmus maximus) and possible influence of exogenous AHLs on bacterial phenotype.

    PubMed

    Zhang, Caili; Zhu, Suqin; Jatt, Abdul-Nabi; Zeng, Mingyong

    2016-01-01

    Quorum sensing (QS) is a cell-to-cell communication mechanism through which microbial cells communicate and regulate their wide variety of biological activities. N-acyl homoserine lactones (AHLs) are considered to be the most important QS signaling molecules produced by several Gram-negative bacteria. The present study aimed to screen the AHLs-producing bacteria from spoiled vacuum-packaged refrigerated turbot (Scophthalmus maximus) by biosensor assays, and the profiles of AHLs produced by these bacteria were determined using reversed-phase thin-layer chromatography (RP-TLC) and gas chromatography-mass spectrometry (GC-MS). Effects of exogenous AHLs and QS inhibitor (QSI) on the phenotypes (i.e., extracellular proteolytic activity and biofilm formation) of the AHLs-producing bacteria were also evaluated. Our results demonstrated that eight out of twenty-two isolates were found to produce AHLs. Three of the AHLs-producing isolates were identified as Serratia sp., and the other five were found to belong to the family of Aeromonas. Two isolates (i.e., S. liquefaciens A2 and A. sobria B1) with higher AHLs-producing activities were selected for further studies. Mainly, RP-TLC and GC-MS analysis revealed three AHLs, i.e., 3-oxo-C6-HSL, C8-HSL and C10-HSL were produced by S. liquefaciens A2, while five AHLs, i.e., C4-HSL, C6-HSL, C8-HSL, C10-HSL, and C12-HSL, were produced by A. sobria B1. Moreover, production of AHLs in both bacterial strains were found to be density-dependent, and the AHLs activity reached a maximum level in their middle logarithmic phase and decreased in the stationary phase. The addition of exogenous AHLs and QSI decreased the specific protease activity both of the Serratia A2 and Aeromonas B1. Exogenous AHLs inhibited the biofilm formation of Serratia A2 while it enhanced the biofilm formation in Aeromonas B1. QSI inhibited the specific protease activity and biofilm formation in both bacterial strains.

  13. Glycosylation of erythrocyte spectrin and its modification in visceral leishmaniasis.

    PubMed

    Samanta, Sajal; Dutta, Devawati; Ghoshal, Angana; Mukhopadhyay, Sumi; Saha, Bibhuti; Sundar, Shyam; Jarmalavicius, Saulius; Forgber, Michael; Mandal, Chhabinath; Walden, Peter; Mandal, Chitra

    2011-01-01

    Using a lectin, Achatinin-H, having preferential specificity for glycoproteins with terminal 9-O-acetyl sialic acid derivatives linked in α2-6 linkages to subterminal N-acetylgalactosamine, eight distinct disease-associated 9-O-acetylated sialoglycoproteins was purified from erythrocytes of visceral leishmaniaisis (VL) patients (RBC(VL)). Analyses of tryptic fragments by mass spectrometry led to the identification of two high-molecular weight 9-O-acetylated sialoglycoproteins as human erythrocytic α- and β-spectrin. Total spectrin purified from erythrocytes of VL patients (spectrin(VL)) was reactive with Achatinin-H. Interestingly, along with two high molecular weight bands corresponding to α- and β-spectrin another low molecular weight 60 kDa band was observed. Total spectrin was also purified from normal human erythrocytes (spectrin(N)) and insignificant binding with Achatinin-H was demonstrated. Additionally, this 60 kDa fragment was totally absent in spectrin(N). Although the presence of both N- and O-glycosylations was found both in spectrin(N) and spectrin(VL), enhanced sialylation was predominantly induced in spectrin(VL). Sialic acids accounted for approximately 1.25 kDa mass of the 60 kDa polypeptide. The demonstration of a few identified sialylated tryptic fragments of α- and β-spectrin(VL) confirmed the presence of terminal sialic acids. Molecular modelling studies of spectrin suggest that a sugar moiety can fit into the potential glycosylation sites. Interestingly, highly sialylated spectrin(VL) showed decreased binding with spectrin-depleted inside-out membrane vesicles of normal erythrocytes compared to spectrin(N) suggesting functional abnormality. Taken together this is the first report of glycosylated eythrocytic spectrin in normal erythrocytes and its enhanced sialylation in RBC(VL). The enhanced sialylation of this cytoskeleton protein is possibly related to the fragmentation of spectrin(VL) as evidenced by the presence of an additional 60

  14. Essential fructosuria: increased levels of fructose 3-phosphate in erythrocytes.

    PubMed

    Petersen, A; Steinmann, B; Gitzelmann, R

    1992-01-01

    Erythrocytes of 3 adult siblings with essential fructosuria contained 45-200 mumol/l fructose 3-phosphate (Fru-3-P), i.e. 3-15 times the concentration in normal controls. Sorbitol 3-phosphate was also increased, but to a lesser degree. An oral load with 50 g of fructose produced an additional 40 mumol/l increase of erythrocyte Fru-3-P after 5 h. The rate of Fru-3-P formation by red cells in vitro was normal. HbA1 and HbA1c were normal. The suspected pathogenetic role of Fru-3-P in diabetic complications is questioned.

  15. Erythrocyte-derived optical nano-vesicles as theranostic agents

    NASA Astrophysics Data System (ADS)

    Mac, Jenny T.; Nunez, Vicente; Bahmani, Baharak; Guerrero, Yadir; Tang, Jack; Vullev, Valentine I.; Anvari, Bahman

    2015-07-01

    We have engineered nano-vesicles, derived from erythrocytes, which can be doped with various near infrared (NIR) organic chromophores, including the FDA-approved indocyanine green (ICG). We refer to these vesicles as NIR erythrocyte-mimicking transducers (NETS) since in response to NIR photo-excitation they can generate heat or emit fluorescent light. Using biochemical methods based on reduction amination, we have functionalized the surface of NET with antibodies to target specific biomolecules. We present results that demonstrate the effectiveness of NETs in targeted imaging of cancer cells that over-express the human epidermal growth factor receptor-2 (HER2).

  16. Erythrocyte membrane fatty acids in multiple myeloma patients.

    PubMed

    Jurczyszyn, Artur; Czepiel, Jacek; Gdula-Argasińska, Joanna; Czapkiewicz, Anna; Biesiada, Grażyna; Dróżdż, Mirosław; Perucki, William; Castillo, Jorge J

    2014-10-01

    Mounting data show that fatty acids (FA) and fatty acid synthase (FAS) function could be potential targets for multiple myeloma (MM) therapy. Our study aimed at comparing the FA composition of erythrocyte membranes of MM patients and healthy controls. MM patients had higher saturated FA and n-6 polyunsaturated FA (PUFA) and lower monounsaturated, n-3 PUFA and trans-FA indices than controls. The n-3/n-6 PUFA ratio was lower in MM patients and there was distinct clustering of variants of individual FA in MM patients. The FA content of erythrocyte membrane could serve as a diagnostic and/or predictive biomarker in MM.

  17. Extraction of DNA from malaria-infected erythrocytes using isotachophoresis.

    PubMed

    Marshall, Lewis A; Han, Crystal M; Santiago, Juan G

    2011-12-15

    We demonstrate a technique for purification of nucleic acids from malaria parasites infecting human erythrocytes using isotachophoresis (ITP). We release nucleic acids from malaria-infected erythrocytes by lysing with heat and proteinase K for 10 min and immediately, thereafter, load sample onto a capillary device. We study the effect of temperature on lysis efficiency. We also implement pressure-driven counterflow during ITP extraction to extend focusing time and increase nucleic acid yield. We show that the purified genomic DNA samples are compatible with polymerase chain reaction (PCR) and demonstrate a clinically relevant limit of detection of 0.5 parasites per nanoliter using quantitative PCR.

  18. Glycosylation of Erythrocyte Spectrin and Its Modification in Visceral Leishmaniasis

    PubMed Central

    Samanta, Sajal; Dutta, Devawati; Ghoshal, Angana; Mukhopadhyay, Sumi; Saha, Bibhuti; Sundar, Shyam; Jarmalavicius, Saulius; Forgber, Michael; Mandal, Chhabinath; Walden, Peter; Mandal, Chitra

    2011-01-01

    Using a lectin, Achatinin-H, having preferential specificity for glycoproteins with terminal 9-O-acetyl sialic acid derivatives linked in α2-6 linkages to subterminal N-acetylgalactosamine, eight distinct disease-associated 9-O-acetylated sialoglycoproteins was purified from erythrocytes of visceral leishmaniaisis (VL) patients (RBCVL). Analyses of tryptic fragments by mass spectrometry led to the identification of two high-molecular weight 9-O-acetylated sialoglycoproteins as human erythrocytic α- and β-spectrin. Total spectrin purified from erythrocytes of VL patients (spectrinVL) was reactive with Achatinin-H. Interestingly, along with two high molecular weight bands corresponding to α- and β-spectrin another low molecular weight 60 kDa band was observed. Total spectrin was also purified from normal human erythrocytes (spectrinN) and insignificant binding with Achatinin-H was demonstrated. Additionally, this 60 kDa fragment was totally absent in spectrinN. Although the presence of both N- and O-glycosylations was found both in spectrinN and spectrinVL, enhanced sialylation was predominantly induced in spectrinVL. Sialic acids accounted for approximately 1.25 kDa mass of the 60 kDa polypeptide. The demonstration of a few identified sialylated tryptic fragments of α- and β-spectrinVL confirmed the presence of terminal sialic acids. Molecular modelling studies of spectrin suggest that a sugar moiety can fit into the potential glycosylation sites. Interestingly, highly sialylated spectrinVL showed decreased binding with spectrin-depleted inside-out membrane vesicles of normal erythrocytes compared to spectrinN suggesting functional abnormality. Taken together this is the first report of glycosylated eythrocytic spectrin in normal erythrocytes and its enhanced sialylation in RBCVL. The enhanced sialylation of this cytoskeleton protein is possibly related to the fragmentation of spectrinVL as evidenced by the presence of an additional 60 kDa fragment, absent in

  19. Abnormalities in the erythrocyte membrane in acute lymphoid leukaemia.

    PubMed Central

    Kundu, M; Basu, J; Chakrabarti, P; Rakshit, M M

    1989-01-01

    Erythrocytes from patients suffering from acute lymphoid leukaemia (ALL) show decreased proportions of spectrin tetrameters and altered spatial distribution of band 4.1 and ankyrins. These abnormalities of the cytoskeleton are probably responsible for altered membrane fluidity and transbilayer distribution of phosphatidylethanolamine in ALL. ALL is associated with severe anaemia and usually, but not always, with overproduction of lymphocytes. To our knowledge, this is the first report of abnormalities in the erythrocyte membrane in ALL which may, in part, be responsible for the observed anaemia. PMID:2730573

  20. [Intermediate phenotype of schizophrenia].

    PubMed

    Hashimoto, Ryota

    2013-04-01

    Genes are major contributors to schizophrenia. The intermediate phenotype concept represents a strategy for identifying risk genes for schizophrenia and for characterizing the neural systems affected by risk gene variants to elucidate quantitative, mechanistic aspects of brain function implicated in schizophrenia. Intermediate phenotypes are defined by being heritable, being able to measure quantitatively; being related to the disorder and its symptoms in the general population; being stable over time; showing increased expression in unaffected relatives of probands; and cosegregation with the disorder in families. Intermediate phenotypes in schizophrenia are neurocognition, neuroimaging, neurophysiology, etc. In this review, we present concept, recent work, and future perspective of intermediate phenotype.

  1. The Influence of Insecticide Resistance, Age, Sex, and Blood Feeding Frequency on Thermal Tolerance of Wild and Laboratory Phenotypes of Anopheles funestus (Diptera: Culicidae).

    PubMed

    Lyons, C L; Oliver, S V; Hunt, R H; Coetzee, M

    2016-03-01

    Resistance to insecticides is a global phenomenon and is increasing at an unprecedented rate. How resistant and susceptible strains of malaria vectors might differ in terms of life history and basic biology is often overlooked, despite the potential importance of such information in light of changing climates. Here, we investigated the upper thermal limits (ULT50) of wild and laboratory strains of Anopheles funestus Giles mosquitoes, including resistance status, sex, age, and blood feeding status as potential factors influencing ULT50. No significant differences in ULT50 were observed between strains displaying different resistance patterns, nor was there a significant difference between wild and laboratory strains. In some instances, strains showed a senescence response, displaying decreased ULT50 with an increase in age, and differences between males and females (females displaying higher ULT50 than males). Blood feeding did not seem to influence ULT50 in any way. For An. funestus, it seems evident that there is no cost to resistance despite what is displayed in other anopheline species. This could have significant impacts for vector control, with resistant populations of An. funestus performing just as well, if not better, than susceptible strains, especially under changing environmental conditions such as those expected to occur with climate change.

  2. The Influence of Insecticide Resistance, Age, Sex, and Blood Feeding Frequency on Thermal Tolerance of Wild and Laboratory Phenotypes of Anopheles funestus (Diptera: Culicidae).

    PubMed

    Lyons, C L; Oliver, S V; Hunt, R H; Coetzee, M

    2016-03-01

    Resistance to insecticides is a global phenomenon and is increasing at an unprecedented rate. How resistant and susceptible strains of malaria vectors might differ in terms of life history and basic biology is often overlooked, despite the potential importance of such information in light of changing climates. Here, we investigated the upper thermal limits (ULT50) of wild and laboratory strains of Anopheles funestus Giles mosquitoes, including resistance status, sex, age, and blood feeding status as potential factors influencing ULT50. No significant differences in ULT50 were observed between strains displaying different resistance patterns, nor was there a significant difference between wild and laboratory strains. In some instances, strains showed a senescence response, displaying decreased ULT50 with an increase in age, and differences between males and females (females displaying higher ULT50 than males). Blood feeding did not seem to influence ULT50 in any way. For An. funestus, it seems evident that there is no cost to resistance despite what is displayed in other anopheline species. This could have significant impacts for vector control, with resistant populations of An. funestus performing just as well, if not better, than susceptible strains, especially under changing environmental conditions such as those expected to occur with climate change. PMID:26718714

  3. A comparison of erythrocyte glutathione S-transferase activity from human foetuses and adults.

    PubMed Central

    Strange, R C; Johnston, J D; Coghill, D R; Hume, R

    1980-01-01

    Glutathione S-transferase activity was measured in partially purified haemolysates of erythrocytes from human foetuses and adults. Enzyme activity was present in erythrocytes obtained between 12 and 40 weeks of gestation. The catalytic properties of the enzyme from foetal cells were similar to those of the enzyme from adult erythrocytes, indicating that probably only one form of the erythrocytes enzyme exists throughout foetal and adult life. PMID:7396875

  4. Study of the Structure, Oxygen-Transporting Functions, and Ionic Composition of Erythrocytes at Vascular Diseases

    PubMed Central

    Revin, Viktor V.; Gromova, Natalia V.; Revina, Elvira S.; Mel'nikova, Natalya A.; Balykova, Larisa A.; Solomadin, Ilia N.; Tychkov, Alexander Yu.; Revina, Nadezhda V.; Gromova, Oksana Yu.; Anashkina, Irina V.; Yakushkin, Viktor A.

    2015-01-01

    The present paper explores the role of erythrocytes in the pathogenesis of vascular diseases. The state of erythrocytes, their ionic composition and structure, and properties of erythrocytes hemoglobin were studied by using laser interference microscopy, Raman scattering spectroscopy, and capillary electrophoresis. In patients suffering from vascular disorders we identified statistically significant changes in the shape of erythrocytes, their ionic composition, and redistribution of hemoglobin throughout cells. PMID:26601112

  5. Python erythrocytes are resistant to α-hemolysin from Escherichia coli.

    PubMed

    Larsen, Casper K; Skals, Marianne; Wang, Tobias; Cheema, Muhammad U; Leipziger, Jens; Praetorius, Helle A

    2011-12-01

    α-Hemolysin (HlyA) from Escherichia coli lyses mammalian erythrocytes by creating nonselective cation pores in the membrane. Pore insertion triggers ATP release and subsequent P2X receptor and pannexin channel activation. Blockage of either P2X receptors or pannexin channels reduces HlyA-induced hemolysis. We found that erythrocytes from Python regius and Python molurus are remarkably resistant to HlyA-induced hemolysis compared to human and Trachemys scripta erythrocytes. HlyA concentrations that induced maximal hemolysis of human erythrocytes did not affect python erythrocytes, but increasing the HlyA concentration 40-fold did induce hemolysis. Python erythrocytes were more resistant to osmotic stress than human erythrocytes, but osmotic stress tolerance per se did not confer HlyA resistance. Erythrocytes from T. scripta, which showed higher osmotic resistance than python erythrocytes, were as susceptible to HlyA as human erythrocytes. Therefore, we tested whether python erythrocytes lack the purinergic signalling known to amplify HlyA-induced hemolysis in human erythrocytes. P. regius erythrocytes increased intracellular Ca²⁺ concentration and reduced cell volume when exposed to 3 mM ATP, indicating the presence of a P2X₇-like receptor. In addition, scavenging extracellular ATP or blocking P2 receptors or pannexin channels reduced the HlyA-induced hemolysis. We tested whether the low HlyA sensitivity resulted from low affinity of HlyA to the python erythrocyte membrane. We found comparable incorporation of HlyA into human and python erythrocyte membranes. Taken together, the remarkable HlyA resistance of python erythrocytes was not explained by increased osmotic resistance, lack of purinergic hemolysis amplification, or differences in HlyA affinity.

  6. Kinetics of viral load and erythrocytic inclusion body formation in pacific herring artificially infected with erythrocytic necrosis virus

    USGS Publications Warehouse

    Glenn, Jolene A.; Emmenegger, Eveline J.; Grady, Courtney A.; Roon, Sean R.; Gregg, Jacob L.; Conway, Carla M.; Winton, James R.; Hershberger, Paul K.

    2012-01-01

    Viral erythrocytic necrosis (VEN) is a condition that affects marine and anadromous fish species, including herrings and salmonids, in the Atlantic and Pacific oceans. Infection is frequently associated with severe anemia and causes episodic mortality among wild and hatchery fish when accompanied by additional stressors; VEN can be presumptively diagnosed by (1) light microscopic identification of a single characteristic—a round, magenta-colored, 0.8-μm-diameter inclusion body (IB) within the cytoplasm of erythrocytes and their precursors on Giemsa-stained blood films; or (2) observation (via transmission electron microscopy [TEM]) of the causative iridovirus, erythrocytic necrosis virus (ENV), within erythrocytes or their precursors. To better understand the kinetics of VEN, specific-pathogen-free Pacific herring Clupea pallasii were infected with ENV by intraperitoneal injection. At 1, 4, 7, 10, 14, 21, and 28 d postexposure, samples of blood, spleen, and kidney were collected and assessed (1) via light microscopy for the number of intracytoplasmic IBs in blood smears and (2) via TEM for the number of virions within erythrocytes. The mean prevalence of intracytoplasmic IBs in the blood cells increased from 0% at 0–4 d postexposure to 94% at 28 d postexposure. Viral load within circulating red blood cells peaked at 7 d postexposure, fell slightly, and then reached a plateau. However, blood cells observed within the kidney and spleen tissues demonstrated high levels of ENV between 14 and 28 d postexposure. The results indicate that the viral load within erythrocytes does not correlate well with IB prevalence and that the virus can persist in infected fish for more than 28 d.

  7. Changes in osmotic fragility of nucleated erythrocytes resulting from blood storage.

    PubMed

    Oyewale, J O

    1994-08-01

    The storage of blood for 24 h at 10 degrees C caused significant changes in osmotic fragility of nucleated erythrocytes of pigeons, peafowls, domestic fowls, lizards and toads. Significant decreases in fragility were seen with pigeon and peafowl erythrocytes. However, the osmotic fragility of domestic fowl, lizard and toad erythrocytes increased significantly.

  8. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme...

  9. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme...

  10. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme...

  11. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme...

  12. 21 CFR 864.7360 - Erythrocytic glucose-6-phosphate dehydrogenase assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythrocytic glucose-6-phosphate dehydrogenase... § 864.7360 Erythrocytic glucose-6-phosphate dehydrogenase assay. (a) Identification. An erythrocytic glucose-6-phosphate dehydrogenase assay is a device used to measure the activity of the enzyme...

  13. Changes in osmotic fragility of nucleated erythrocytes resulting from blood storage.

    PubMed

    Oyewale, J O

    1994-08-01

    The storage of blood for 24 h at 10 degrees C caused significant changes in osmotic fragility of nucleated erythrocytes of pigeons, peafowls, domestic fowls, lizards and toads. Significant decreases in fragility were seen with pigeon and peafowl erythrocytes. However, the osmotic fragility of domestic fowl, lizard and toad erythrocytes increased significantly. PMID:7863738

  14. [Physical essence of erythrocytic sedimentation rate in the gravitation field of the earth].

    PubMed

    Cherniĭ, A N

    2009-01-01

    The erythrocytic sedimentation rate method has been long known in medicine and extensively used in laboratory practice in tuberculosis facilities. However, many authors note that the erythrocytic sedimentation rate phenomenon has not clearly understood. By applying the total theory of relativity and quantum mechanics, the author discloses the physical essence of erythrocytic sedimentation in the gravitation field of the Earth.

  15. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Erythrocyte sedimentation rate test. 864.6700 Section 864.6700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700...

  16. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Erythrocyte sedimentation rate test. 864.6700 Section 864.6700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700...

  17. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythrocyte sedimentation rate test. 864.6700 Section 864.6700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700...

  18. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Erythrocyte sedimentation rate test. 864.6700 Section 864.6700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700...

  19. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Erythrocyte sedimentation rate test. 864.6700 Section 864.6700 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700...

  20. Erythrocyte antioxidant protection of rose hips (Rosa spp.).

    PubMed

    Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

    2012-01-01

    Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

  1. The effect of bromfenvinphos and its impurities on human erythrocyte.

    PubMed

    Szatkowska, Bozena; Bukowska, Bozena; Huras, Bogumiła

    2011-02-01

    Bromfenvinphos - (E,Z)-O,O-diethyl-O-[1-(2,4-dichlorophenyl)-2-bromovinyl] phosphate (BFVF) is the insecticide elaborated in Poland, which has been used against Varroa destructor causing honey bees disease called as varroosis. The substances that are formed as a result of bromfenvinphos synthesis are dihydro-bromfenvinphos (O,O-diethyl O-[1-(2,4-dichlorophenyl)vinyl] phosphate); dibromo-bromfenvinphos (O,O-diethyl O-[1-(2,4-dichlorophenyl)-2,2-dibromovinyl] phosphate); 2,4-dichlorophenacyl bromide; 2,4-dichlorophenacylidene bromide and 2,4-dichlorophenacylidyne bromide. In this work, we evaluated the effect of these compounds on hemolysis and hemoglobin oxidation (met-Hb formation) in human erythrocytes. Moreover, the changes in the size (FSC-A) and the shape (SSC-A) of red blood cells were assessed using flow cytometry and phase contrast microscopy. It was proven that bromfenvinphos at concentrations ranging from 0.5 to 250 μM during 1h incubation did not change the parameters examined in human erythrocytes. Similarly, most of bromfenvinphos impurities did not increase hemolysis and methemoglobin level nor changed the size and shape of the erythrocytes. The exception was dibromo-bromfenvinphos, which changed the FSC-A and SSC-A parameters, as well as 2,4-dichlorophenacyl bromide which induced hemolysis, increased the level of met-Hb and changed erythrocytes morphology.

  2. MODULATION OF HYPOXIC PULMONARY VASOCONSTRICTION BY ERYTHROCYTIC NITRIC OXIDE

    EPA Science Inventory

    Abstract
    American Heart Association 2001

    Modulation of Hypoxic Pulmonary Vasoconstriction by Erythrocytic NO
    McMahon TJ1, Gow AJ1, Huang YCT4, Stamler JS1,2,3
    Departments of Medicine1 and Biochemistry2, and Howard Hughes Medical Institute3,
    Duke University Med...

  3. Age-related carbonyl stress and erythrocyte membrane protein carbonylation.

    PubMed

    Li, Guolin; Liu, Li; Hu, Hui; Zhao, Qiong; Xie, Fuxia; Chen, Keke; Liu, Shenglin; Chen, Yaqin; Shi, Wang; Yin, Dazhong

    2010-01-01

    Reactive carbonyl species (RCS) have been widely used as indicators of oxidative stress. However, the associations of carbonyl stress with aging process and biochemical alteration of erythrocyte are still poorly understood. Fresh blood samples in vacutainer tubes containing sodium heparinate were obtained from 874 volunteers who were divided into young, adult and old groups based on their age. Plasma RCS and thiols concentrations between different age groups and erythrocyte membrane protein carbonylation in the adult group were detected within 24h of the blood sampling. Results showed that the plasma thiols concentration decreased gradually during aging process, and the p-values between all three groups are less than 0.05. The plasma RCS concentration in different age groups showed a nonlinear association with age. The levels in the young group were slightly higher than the adult group (not significant) and lower than the old group (p < 0.01). The protein carbonylation of erythrocyte membrane was positively correlated with plasma RCS concentration (p < 0.01), but not plasma thiols concentration. We conclude that higher levels of RCS, not lower levels of thiols, in plasma are a direct risk factor for the protein carbonylation of erythrocyte membrane. Owing to the decrease of thiols levels and increase of RCS levels during aging process, a shift from RCS-related redox allostasis to carbonyl stress would contribute to age-related biological dysfunction and even aging process.

  4. The anticancer drug adriamycin interacts with the human erythrocyte membrane.

    PubMed

    Suwalsky, M; Hernández, P; Villena, F; Aguilar, F; Sotomayor, C P

    1999-01-01

    Adriamycin is an aminoglycosidic anthracycline antibiotic widely used in the treatment of cancer. Increasing reports point to the involvement of cell membranes in its mechanism of action. The interaction of adriamycin with human erythrocytes was investigated in order to determine the membrane binding sites and the resultant structural perturbation. Electron microscopy revealed that red cells incubated with the therapeutical concentration of the drug in human plasma changed their discoid shape to both stomatocytes and echinocytes. According to the bilayer couple hypothesis, this means that adriamycin was incorporated into either the inner or outer leaflets of the erythrocyte membrane. To explain this unusual result, the drug was incubated with molecular models. One of them consisted of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) multilayers, representative of phospholipid classes located in the outer and inner leaflets of the erythrocyte membrane, respectively. X-ray diffraction showed that adriamycin interaction perturbed the polar head and acyl chain regions of both lipids. Fluorescence spectroscopy on another model, consisting of DMPC large unilamellar vesicles (LUV), confirmed the X-ray results in that adriamycin fluidized its hydrophobic moiety. It is concluded that adriamycin incorporates into both erythrocyte leaflets affecting its membrane structure. PMID:10349743

  5. Associations of erythrocyte fatty acid patterns with insulin resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Synergistic and/or additive effects on cardiometabolic risk may be missed by examining individual fatty acids (FA). A pattern analysis may be a more useful approach. As well, it remains unclear whether erythrocyte fatty acid composition relates to insulin resistance among Hispanic/Latino...

  6. [VISCOELASTISITY AND ELECTRICAL PARAMETERS OF ERYTHROCYTES IN GILBERT SYNDROME].

    PubMed

    Kurilovich, S A; Nemtsova, E G; Kruchinina, M V; Maximov, V N

    2015-01-01

    Results of viscoelastic and electrical properties of erythrocytes study in patients with genetically confirmed Gilbert's syndrome (n = 81) are presented. Dielectrophoresis of erythrocytes in a nonuniform an alterning electric field was performed in81 patients with Gilbert's syndrome and in 20 persons of the comparison group without of the pathology identified by thelaboratory and instrumental examination. The significant differences in viscoelasticity properties of erythrocytes in Gilbert'ssyndrome were obtained. The amplitude of the deformation, the speed of movement to the electrodes and the polarizability on electric field's of all frequencies were significantly lower, but generalized rigidity index, viscosity, index of aggregationand degradation on electric field's of all frequencies were higher than in the comparison group. A number of electricalparameters (conductivity, the capacity of the cells and the relative polarizability) were also higher than in the comparisongroup. Some differences in the parameters of erythrocytes were obtained from homozygous and heterozygous carriers of A(TA), TAA of gene UGT1A1 promotor. PMID:27214984

  7. Phosphorylation of intact erythrocytes in human muscular dystrophy

    SciTech Connect

    Johnson, R.M.; Nigro, M.

    1986-04-01

    The uptake of exogenous /sup 32/Pi into the membrane proteins of intact erythrocytes was measured in 8 patients with Duchenne muscular dystrophy. No abnormalities were noted after autoradiographic analysis. This contrasts with earlier results obtained when isolated membranes were phosphorylated with gamma-(/sup 32/P)ATP, and suggests a possible reinterpretation of those experiments.

  8. Changes in erythrocytic deformability and plasma viscosity in neonatal ictericia.

    PubMed

    Bonillo-Perales, A; Muñoz-Hoyos, A; Martínez-Morales, A; Molina-Carballo, A; Uberos-Fernández, J; Puertas-Prieto, A

    1999-01-01

    We studied 45 full-term newborns divided into 3 groups. Group 1: 17 newborns with bilirubin <10 mg/dL; Group 2: 18 newborns with hemolytic ictericia (bilirubin 11-20 mg/dL) and Group 3: 10 newborns with moderate hemolytic ictericia needing exchange transfusion. The following were studied: erythrocytic deformability, plasma viscosity, plasmatic osmolarity, seric bilirubin, bilirubin/albumin ratio, free fatty acids and corpuscular volume of the erythrocytes. In full-term newborns, the following are risk factors for increased erythrocytic rigidity: neonatal hemolytic illness (p = 0.004, odds ratio: 7.02), increases in total bilirubin (p = 0.02, odds ratio: 4.3) and increases in the bilirubin/albumin ratio (p = 0.025, odds ratio: 4.25). Furthermore, the most important risk factor for high plasma viscosity is also neonatal hemolytic illness (p = 0.01, odds ratio: 2.30). The role of total bilirubin is also important (p = 0.09, odds ratio: 2.10), while that of the bilirubin/albumin ratio (p = 0.012, NS) is less so. The greater the hemolysis, the greater the erythrocytic rigidity and plasma viscosity (p < 0.01). In full-term newborns with moderate ictericia, hemolytic illness and increases in the bilirubin/albumin ratio are accompanied by rheological alterations that could affect cerebral microcirculation and cause a neurological deficit not exclusively related to the levels of bilirubin in plasma.

  9. Effect of high glucose concentrations on human erythrocytes in vitro

    PubMed Central

    Viskupicova, Jana; Blaskovic, Dusan; Galiniak, Sabina; Soszyński, Mirosław; Bartosz, Grzegorz; Horakova, Lubica; Sadowska-Bartosz, Izabela

    2015-01-01

    Exposure to high glucose concentrations in vitro is often employed as a model for understanding erythrocyte modifications in diabetes. However, effects of such experiments may be affected by glucose consumption during prolonged incubation and changes of cellular parameters conditioned by impaired energy balance. The aim of this study was to compare alterations in various red cell parameters in this type of experiment to differentiate between those affected by glycoxidation and those affected by energy imbalance. Erythrocytes were incubated with 5, 45 or 100 mM glucose for up to 72 h. High glucose concentrations intensified lipid peroxidation and loss of activities of erythrocyte enzymes (glutathione S-transferase and glutathione reductase). On the other hand, hemolysis, eryptosis, calcium accumulation, loss of glutathione and increase in the GSSG/GSH ratio were attenuated by high glucose apparently due to maintenance of energy supply to the cells. Loss of plasma membrane Ca2+-ATPase activity and decrease in superoxide production were not affected by glucose concentration, being seemingly determined by processes independent of both glycoxidation and energy depletion. These results point to the necessity of careful interpretation of data obtained in experiments, in which erythrocytes are subject to treatment with high glucose concentrations in vitro. PMID:26141922

  10. Oscillatory tank-treading motion of erythrocytes in shear flows

    PubMed Central

    Dodson, W. R.; Dimitrakopoulos, P.

    2013-01-01

    In this paper, we investigate the oscillatory dynamics of the tank-treading motion of healthy human erythrocytes in shear flows with capillary number Ca = O(1) and small to moderate viscosity ratios 0.01 ≤ λ ≤ 1.5. These conditions correspond to a wide range of surrounding medium viscosities (4 to 600 mPa s) and shear flow rates (2 to 560 s−1), and match those used in ektacytometry systems. For a given viscosity ratio, as the flow rate increases, the steady-state erythrocyte length L (in the shear plane) increases logarithmically while its depth W (normal to the shear plane) decreases logarithmically. In addition, the flow rate increase dampens the oscillatory erythrocyte inclination but not its lengths oscillations (which show relative variations of about 5–8%). For a given flow rate, as the viscosity ratio increases, the erythrocyte length L contracts while its depth W increases (i.e. the cell becomes less deformed) with small decrease in the lengths variations. The average orientation angle of the erythrocyte shows a significant decrease with the viscosity ratio as does the angle oscillation while the oscillation period increases. These trends continue in higher viscosity ratios resulting eventually in the transition from a (weakly oscillatory) tank-treading motion to a tumbling motion. Our computations show that the erythrocyte width S, which exists in the shear plane, is practically invariant in time, capillary number and viscosity ratio, and corresponds to a real cell thickness of about 2.5 μm. Comparison of our computational results with the predictions of (low degree-of-freedom) theoretical models and experimental findings, suggests that the energy dissipation due to the shape-memory effects is more significant than the energy dissipation due to the membrane viscosity. Our work shows that the oscillatory tank-treading motion can account for more than 50% of the variations found in ektacytometry systems; thus, researchers who wish to study inherent

  11. Oscillatory tank-treading motion of erythrocytes in shear flows.

    PubMed

    Dodson, W R; Dimitrakopoulos, P

    2011-07-01

    In this paper, we investigate the oscillatory dynamics of the tank-treading motion of healthy human erythrocytes in shear flows with capillary number Ca = O(1) and small to moderate viscosity ratios 0.01 ≤ λ ≤ 1.5. These conditions correspond to a wide range of surrounding medium viscosities (4-600 m Pa s) and shear flow rates (2-560 s(-1)), and match those used in ektacytometry systems. For a given viscosity ratio, as the flow rate increases, the steady-state erythrocyte length L (in the shear plane) increases logarithmically while its depth W (normal to the shear plane) decreases logarithmically. In addition, the flow rate increase dampens the oscillatory erythrocyte inclination but not its length oscillations (which show relative variations of about 5-8%). For a given flow rate, as the viscosity ratio increases, the erythrocyte length L contracts while its depth W increases (i.e., the cell becomes less deformed) with a small decrease in the length variations. The average orientation angle of the erythrocyte shows a significant decrease with the viscosity ratio as does the angle oscillation while the oscillation period increases. These trends continue in higher viscosity ratios resulting eventually in the transition from a (weakly oscillatory) tank-treading motion to a tumbling motion. Our computations show that the erythrocyte width S, which exists in the shear plane, is practically invariant in time, capillary number, and viscosity ratio, and corresponds to a real cell thickness of about 2.5 μm. Comparison of our computational results with the predictions of (low degree-of-freedom) theoretical models and experimental findings, suggests that the energy dissipation due to the shape-memory effects is more significant than the energy dissipation due to the membrane viscosity. Our work shows that the oscillatory tank-treading motion can account for more than 50% of the variations found in ektacytometry systems; thus, researchers who wish to study inherent

  12. Erythrocyte membrane composition in patients with primary hypercholesterolemia.

    PubMed

    Vayá, A; Martínez Triguero, M; Réganon, E; Vila, V; Martínez Sales, V; Solá, E; Hernández Mijares, A; Ricart, A

    2008-01-01

    There are conflicting results regarding the erythrocyte membrane cholesterol and phospholipid content in patients with primary hypercholesterolemia (PHC), due to methodological problems in obtaining haemoglobin-free ghosts. At the same time, the different units used and the fact that the cholesterol and phospholipids are not expressed in relation with integral protein membrane content, produces contradictory results. We have analysed in 33 patients with PHC (12 male, 31 female) aged 43+/-12 years and in 33 healthy normolipaemic volunteers (9 male, 24 female) aged 43+/-13 years plasma lipids, along with, erythrocyte membrane cholesterol, phospholipids and integral proteins. PHC patients showed increased erythrocyte membrane cholesterol: 0.36+/-0.15 mg/mg when compared with controls: 0.29+/-0.75 mg/mg; p=0.018. Phospholipid membrane content, although higher in the cases, did not reach statistical significance (PHC patients: 0.38+/-0.15 mg/mg vs. 0.33+/-0.72 mg/mg; p=0.098). The cholesterol/phospholipids ratio (Chol/Ph) was 0.99+/-0.22 in PHC patients versus 0.92+/-0.28 in controls; p=0.127. Our results suggest that there is a slight increase in erythrocyte membrane cholesterol in patients with PHC. Given the increasing importance of erythrocyte membrane cholesterol in the stability of the atheroma plaque due its possible contribution to the clinical signs of ischaemic heart disease, it seems relevant to determine this parameter in risk populations. Therefore, a simple and reproducible method needs to be standardised which would enable comparisons between laboratories and facilitate further studies aimed to it as a marker of acute coronary syndromes.

  13. Human erythrocytes are affected by the organochloride insecticide chlordane.

    PubMed

    Suwalsky, M; Rodríguez, C; Villena, F; Sotomayor, C P

    2005-05-01

    Chlordane is a widely used organochlorine insecticide. In order to evaluate its perturbing effect upon the morphology of human erythrocytes it was caused to interact with human red cells and molecular models of cell membranes. These consisted in bilayers of dimyristoylphosphatidylethanolamine (DMPE) and of dimyristoylphosphatidylcholine (DMPC), representative of phospholipid classes located in the inner and outer monolayers of the erythrocyte membrane, respectively. Scanning electron microscopy (SEM) observations indicated that this pesticide induced a significant alteration in the shape of the erythrocytes as they changed their discoid shape to spherocytes. According to the bilayer couple hypothesis, the shape changes induced in erythrocytes by foreign molecules are due to differential expansion of their two monolayers. The fact that chlordane produced spherocytes would indicate that the pesticide was equally located in the outer and the inner moieties of the red cell membrane. This conclusion was supported by the results obtained from X-ray diffraction studies. These showed that the hydrophobic and polar head regions of DMPC bilayers were perturbed when the insecticide was in a 1:10 molar ratio with respect to the lipid. These results were confirmed by the fluorescence experiments performed in DMPC large unilamellar vesicles (LUV). Chlordane produced a sharp decrease in the anisotropy and general polarization parameters in the 0-0.1 mM range, implying an increase in the fluidity at the acyl chain and polar region of DMPC. On the other hand, the bilayer structure of DMPE was perturbed in a fashion similar to that observed by X-ray diffraction in DMPC, a fact that explains the morphological change induced by chlordane to the human erythrocytes. PMID:15778003

  14. Stimulation of erythrocyte phosphatidylserine exposure by mercury ions

    SciTech Connect

    Eisele, Kerstin; Lang, Philipp A.; Kempe, Daniela S.; Klarl, Barbara A.; Niemoeller, Olivier; Wieder, Thomas; Huber, Stephan M.; Duranton, Christophe; Lang, Florian . E-mail: florian.lang@uni-tuebingen.de

    2006-01-15

    The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg{sup 2+}-induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg{sup 2+} in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca{sup 2+}-sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca{sup 2+} activity and/or activate a sphingomyelinase leading to formation of ceramide. Ceramide sensitizes the scramblase to Ca{sup 2+}. The present experiments explored the effect of Hg{sup 2+} ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg{sup 2+} (1 {mu}M) indeed significantly increased annexin binding from 2.3 {+-} 0.5% (control condition) to 23 {+-} 6% (n = 6). This effect was paralleled by activation of a clotrimazole-sensitive K{sup +}-selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by {approx}66% (n = 7) after challenge with mercury (1 {mu}M). In conclusion, mercury ions activate a clotrimazole-sensitive K{sup +}-selective conductance leading to transient cell shrinkage. Moreover, Hg{sup 2+} increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg{sup 2+}.

  15. [Ratio of erythrocyte and plasma in massive blood transfusion].

    PubMed

    Wen, Xian-Hui; Liu, Feng-Xia; Zhang, Jun-Hua; Gui, Rong

    2014-06-01

    This study was purposed to explore the suitable ratio between fresh frozen plasma and erythrocyte by retrospective analysis of coagulation in patients with massive blood transfusion. The clinical data of 151 cases with massive blood transfusion from January 2011 to January 2013 were analyzed retrospectively. According to coagulation, patients were divided into coagulation normal group (138 cases) and coagulation dysfunction group (13 cases). Based on the ratio of 1:1 of fresh frozen plasma and erythrocyte, the patients were divided into high plasma group(2:1), medium plasma group (1:1) and low plasma (<1:1) subgroups. Coagulation was detected before and after 24 h of massive blood transfusion. The results showed that prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) were prolonged, fibrinogen (FIB) level decreased significantly (all P < 0.05) in the low plasma subgroup of coagulation normal group after massive blood transfusion 24 h; the high plasma and the medium plasma group of coagulation normal group had no significant changes in coagulation (P > 0.05); prothrombin time, activated partial thromboplastin time, thrombin time and fibrinogen level in the medium plasma and low plasma subgroup of coagulation dysfunction group after massive transfusion was still in abnormal levels (P > 0.05), coagulation function in high plasma subgroup was improved significantly (P < 0.05). It is concluded that the ratio of plasma to erythrocyte should be adjusted according to the patient's coagulation function during massive blood transfusion, the ratio between fresh frozen plasma and erythrocyte is recommended to be 2:1 in patients of coagulation dysfunction in order to improve the patient's coagulation function and to reduce the incidence of adverse event, the ratio of fresh frozen plasma to erythrocyte is recommended to be 1:1 in patients with normal coagulation so as to reduce the dilutional coagulopathy and hypervolemia of blood.

  16. Red wine activates plasma membrane redox system in human erythrocytes.

    PubMed

    Tedesco, Idolo; Moccia, Stefania; Volpe, Silvestro; Alfieri, Giovanna; Strollo, Daniela; Bilotto, Stefania; Spagnuolo, Carmela; Di Renzo, Massimo; Aquino, Rita P; Russo, Gian Luigi

    2016-01-01

    In the present study, we report that polyphenols present in red wine obtained by a controlled microvinification process are able to protect human erythrocytes from oxidative stress and to activate Plasma Membrane Redox System (PMRS). Human plasma obtained from healthy subjects was incubated in the presence of whole red wine at a concentration corresponding to 9.13-73 μg/ml gallic acid equivalents to verify the capacity to protect against hypochlorous acid (HOCl)-induced plasma oxidation and to minimize chloramine formation. Red wine reduced hemolysis and chloramine formation induced by HOCl of 40 and 35%, respectively. PMRS present on human erythrocytes transfers electrons from intracellular molecules to extracellular electron acceptors. We demonstrated that whole red wine activated PMRS activity in human erythrocytes isolated from donors in a dose-dependent manner with a maximum at about 70-100 μg/ml gallic acid equivalents. We also showed that red wine increased glutathione (GSH) levels and erythrocytic antioxidant capacity, measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) quenching assay. Furthermore, we reported that GSH played a crucial role in regulating PMRS activity in erythrocytes. In fact, the effect of iodoacetamide, an alkylating agent that induces depletion of intracellular GSH, was completely counteracted by red wine. Bioactive compounds present in red wine, such as gallic acid, resveratrol, catechin, and quercetin were unable to activate PMRS when tested at the concentrations normally present in aged red wines. On the contrary, the increase of PMRS activity was associated with the anthocyanin fraction, suggesting the capacity of this class of compounds to positively modulate PMRS enzymatic activity.

  17. P. falciparum: merozoite surface protein-8 peptides bind specifically to human erythrocytes.

    PubMed

    Puentes, Alvaro; García, Javier; Ocampo, Marisol; Rodríguez, Luis; Vera, Ricardo; Curtidor, Hernando; López, Ramsés; Suarez, Jorge; Valbuena, John; Vanegas, Magnolia; Guzman, Fanny; Tovar, Diana; Patarroyo, Manuel E

    2003-07-01

    This work determined Plasmodium falciparum merozoite surface protein-8 (MSP-8) regions specifically binding to membrane surface receptors on human erythrocytes. Five high activity binding peptides (HABPs), whose binding to erythrocytes became saturable and sensitive on being treated with neuraminidase and chymotrypsin were identified from the MSP-8 protein. Those amino acids directly involved in interaction with erythrocytes were also determined for each one of the HABPs. Some of them specifically recognized 28, 46, and 73 kDa erythrocyte membrane proteins. Some HABPs inhibited in vitro P. falciparum merozoite invasion of erythrocytes by up to 98%, suggesting the MSP-8 protein's possible role in the invasion process.

  18. The physiologic role of erythrocytes in oxygen delivery and implications for blood storage.

    PubMed

    Benedik, Penelope S; Hamlin, Shannan K

    2014-09-01

    Erythrocytes are not just oxygen delivery devices but play an active metabolic role in modulating microvascular blood flow. Hemoglobin and red blood cell morphology change as local oxygen levels fall, eliciting the release of adenosine triphosphate and nitric oxide to initiate local vasodilation. Aged erythrocytes undergo physical and functional changes such that some of the red cell's most physiologically helpful attributes are diminished. This article reviews the functional anatomy and applied physiology of the erythrocyte and the microcirculation with an emphasis on how erythrocytes modulate microvascular function. The effects of cell storage on the metabolic functions of the erythrocyte are also briefly discussed.

  19. Hemorheological changes and hematometric erythrocyte characteristics in rats after sodium nitrite intoxication

    NASA Astrophysics Data System (ADS)

    Ivanov, Ivan; Gluhcheva, Yordanka; Petrova, Emilia; Antonova, Nadia

    2014-05-01

    Sodium nitrite (NaNO2) is a precursor to a variety of organic compounds (pharmaceuticals, dyes and pesticides), but it is best known as a food additive. The aim of the study is to investigate the influence of acute (i.p.) treatment of Wistar rats with NaNO2 (at the dose of 50 mg/kg b.w.) on the blood rheological properties and erythrocyte hematometric indices (Hb, HCT, RBC, MCV, RDW, MCH, MCHC). The significant differences were not found in the whole blood viscosity (WBV) values of the control and NaNO2-treated groups. The changes in the erythrocyte hematometric indices were statistically significant for RDW, MCHC and MCH at the 1st hour, five- and ten days after NaNO2 administration. Interestingly, at the day 5th of the NaNO2 treatment we obtained statistically significant lower values for the RBC count, Hb, HCT, RDW, as well as elevated indices MCV (no statistically significant), MCH, MCHC. The results obtained indicate that hemorheological and hematometric parameters examined should be monitored in cases of acute exposure to nitrites — for the purposes of clinical toxicology. The quantitative values of hematometric indices reported in our experimental model could be suitable for predicting NaNO2 intoxication and methemoglobinemia in animals and humans.

  20. Plasma and erythrocyte phospholipid fatty acid profile in professional basketball and football players.

    PubMed

    Tepsic, Jasna; Vucic, Vesna; Arsic, Aleksandra; Blazencic-Mladenovic, Vera; Mazic, Sanja; Glibetic, Marija

    2009-10-01

    The effect of intensive long-term physical activity on phospholipid fatty acid (FA) composition has not been studied thoroughly. We determined plasma and erythrocyte phospholipid FA status of professional basketball and football players. Our results showed differences in plasma FA profile not only between sportsmen and sedentary subjects, but also between two groups of sportsmen. Plasma FA profile in basketball players showed significantly higher proportion of n-6 FA (20:3, 20:4, and 22:4) and total polyunsaturated FA (PUFA) than controls, while football players had higher palmitoleic acid (16:1) than basketball players and controls. Total PUFA and 22:4 were also higher in basketball than in football players. Erythrocyte FA profile showed no differences between football players and controls. However, basketball players had higher proportion of 18:0 than controls, higher saturated FA and lower 18:2 than two other groups, and higher 22:4 than football players. These findings suggest that long-term intensive exercise and type of sport influence FA profile.

  1. Differences in phenotype and gene expression of prostate stromal cells from patients of varying ages and their influence on tumour formation by prostate epithelial cells

    PubMed Central

    Wang, Yong-Chuan; Yu, Sheng-Qiang; Wang, Xiao-Hai; Han, Bang-Min; Zhao, Fu-Jun; Zhu, Guang-Hui; Hong, Yan; Xia, Shu-Jie

    2011-01-01

    Prostate cancer (PCa) is an age-related disease, and the stromal microenvironment plays an important role in prostatic malignant progression. However, the differences in prostate stromal cells present in young and old tissue are still obscure. We established primary cultured stromal cells from normal prostatic peripheral zone (PZ) of donors of varying ages and found that cultured stromal cells from old donors (PZ-old) were more enlarged and polygonal than those from young donors (PZ-young). Furthermore, based on immunocytochemical and ultrastructural analysis, the components of stromal cells changed from a majority of fibroblasts to a mixture of fibroblasts and myofibroblasts with increasing donor age. Using a three-dimensional in vitro culture system, we found that PZ-old stromal cells could enhance the proliferation, migration and invasion of cocultured benign BPH-1 and PC-3 cells. Using an in vivo tissue recombination system, we also found that PZ-old stromal cells are more effective than PZ-young cells in promoting tumour formation by BPH-1 cells of high passage(>100) and PC-3 cells. To probe the possible mechanism of these effects, we performed cDNA microarray analysis and profiled 509 upregulated genes and 188 downregulated genes in PZ-old cells. Among the changed genes, we found genes coding for a subset of paracrine factors that are capable of influencing adjacent epithelial cells; these include hepatocyte growth factor (HGF), fibroblast growth factor 5 (FGF5), insulin-like growth factor 2 (IGF2), insulin-like growth factor-binding protein 4 (IGFBP4), IGFBP5 and matrix metallopeptidase 1 (MMP1). Changes in the expression of these genes were further confirmed by quantitative real-time polymerase chain reaction (PCR), Western blotting and enzyme-linked immunosorbent assays. Overall, our findings indicate that stromal cells from prostate PZ of old donors are more active than similar cells from young donors in promoting the malignant process of adjacent

  2. Attempts to validate a possible predictive animal model for human erythrocyte G-6-PD deficiency

    SciTech Connect

    Horton, H.M.; Calabrese, E.J.

    1986-01-01

    The use of Dorset sheep erythrocytes as a model for human G-6-PD deficient erythrocytes was investigated. Seven pharmaceuticals were examined for oxidant stressor effects using a liver microsomal enzyme system to generate metabolites of the drugs. The pharmaceuticals examined were salicyclic acid, dapsone, naphthalene, B-naphtol, p-aminobenzoic acid, sulfanilamide and sulfapyridine. The test compounds were incubated with Dorset sheep erythrocytes and oxidant stressor effects were measured through reduced glutathione (GSH) levels and methemaglobin formation. The response of the Dorset sheep erythrocytes to the seven agents was compared to previous studies revealing the response of human G-6-PD deficient erythrocytes to these agents. The results indicated that metabolites of the pharmaceuticals, B-naphthol, dapsone, and sulfanilamide, are oxidant stressor agents towards sheep G-6-PD deficient erythrocytes. These results agreed with studies on the response of human G-6-PD deficient erythrocytes. The metabolized naphthalene and sulfapyridine did not cause oxidant stress in the sheep erythrocytes, despite the fact that these two agents caused oxidizing effects in human G-6-PD deficient erythrocytes in previous studies. None of the non-metabolized parent compounds caused oxidant stress in the sheep erythrocytes, which agreed with the responses of human G-6-PD deficient erythrocytes.

  3. The Drosophila phenotype ontology

    PubMed Central

    2013-01-01

    Background Phenotype ontologies are queryable classifications of phenotypes. They provide a widely-used means for annotating phenotypes in a form that is human-readable, programatically accessible and that can be used to group annotations in biologically meaningful ways. Accurate manual annotation requires clear textual definitions for terms. Accurate grouping and fruitful programatic usage require high-quality formal definitions that can be used to automate classification. The Drosophila phenotype ontology (DPO) has been used to annotate over 159,000 phenotypes in FlyBase to date, but until recently lacked textual or formal definitions. Results We have composed textual definitions for all DPO terms and formal definitions for 77% of them. Formal definitions reference terms from a range of widely-used ontologies including the Phenotype and Trait Ontology (PATO), the Gene Ontology (GO) and the Cell Ontology (CL). We also describe a generally applicable system, devised for the DPO, for recording and reasoning about the timing of death in populations. As a result of the new formalisations, 85% of classifications in the DPO are now inferred rather than asserted, with much of this classification leveraging the structure of the GO. This work has significantly improved the accuracy and completeness of classification and made further development of the DPO more sustainable. Conclusions The DPO provides a set of well-defined terms for annotating Drosophila phenotypes and for grouping and querying the resulting annotation sets in biologically meaningful ways. Such queries have already resulted in successful function predictions from phenotype annotation. Moreover, such formalisations make extended queries possible, including cross-species queries via the external ontologies used in formal definitions. The DPO is openly available under an open source license in both OBO and OWL formats. There is good potential for it to be used more broadly by the Drosophila

  4. The association between erythrocyte internal viscosity, protein non-enzymatic glycosylation and erythrocyte membrane dynamic properties in juvenile diabetes mellitus.

    PubMed Central

    Watala, C.; Witas, H.; Olszowska, L.; Piasecki, W.

    1992-01-01

    The association of intracellular viscosity of red blood cells and the dynamic properties of erythrocyte membranes in children suffering from diabetes has been investigated by means of ESR spectroscopy. It has been revealed that the slight decrease in the ratio hw/hs of maleimide bound to membrane protein-SH groups of erythrocytes in diabetes may ensue from the enhanced membrane protein immobilization in the plane of lipid bilayer. These alterations were accompanied by a corresponding increase in the relative rotational correlation time (tau c) of iodoacetamide spin label, thus suggesting that the conformational changes in membrane proteins may occur at both the intrinsic and more exposed thiol groups. The membranes of diabetic red blood cells were more glycosylated than those of relevant controls, and the extent of glycosylation was found to correlate significantly with h + 1/h0 and tau c (r = -0.652, P < 0.01 and r = 0.609, P < 0.01). Further, the conformational alterations in erythrocyte membranes from diabetic subjects were accompanied by a significant increase in the mobility parameter (h + 1/h0) of haemoglobin molecules in diabetic erythrocytes. The latter changes correlated well with the enhanced intracellular viscosity of diabetic red blood cells and the level of glycosylated haemoglobin. We conclude that the alterations in membrane lipid-protein interactions together with the increased glycosylation-derived internal viscosity may consequently imply altered viscoelastic properties of erythrocyte membranes and, underlying the impaired deformability of red blood cells in the diabetic state, contribute to the development of late diabetic sequelae. PMID:1329916

  5. [Effect of erythrocyte preserved for different lengths of time on anti-D antibody identification with three blood matching tests].

    PubMed

    Xiao, Rui-Qing; Lin, Wu-Cun; Xu, Dan; Zeng, Jie; Wu, Jian-Jun; Zhao, Shu-Ming

    2003-10-01

    The specificity of the antigens and length of preservation time of erythrocytes are the interfering factors in blood group serological tests. In order to clarify the influence of preservation time of erythrocytes on the blood matching test, the titers of anti-D antibody were detected with papain method, BioVue cross matching card and DianaGel cross matching card in 7 series of panel red blood cells preserved for various length of time (0 to 9 months). The results showed that the titer of micro-column gel test (DianaGel card) was one tube higher than that of column agglutinating test (BioVue card). The titer of erythrocytes preserved for 9 months was as high as 256 tested by DianaGel card, but it was only 2 by papain method in the same anti-serum. It is suggested that there was no obvious difference between the results of micro-column gel test and column agglutinating test, and titer of papain method was the lowest. PMID:14575550

  6. Tank-treading of swollen erythrocytes in shear flows

    NASA Astrophysics Data System (ADS)

    Dodson, W. R., III; Dimitrakopoulos, P.

    2012-02-01

    In this paper, we investigate computationally the oscillatory tank-treading motion of healthy swollen human erythrocytes (owing to lower than physiological plasma osmolarity) in shear flows with capillary number Ca=O(1) and small to moderate viscosity ratios 0.01≤λ≤2.75. Swollen cells show similar shear flow dynamics with normal cells but with significantly higher inclination and tank-treading speed owing to the higher cell thickness. For a given viscosity ratio, as the flow rate increases, the steady-state erythrocyte length L (in the shear plane) increases logarithmically while its depth W (normal to the shear plane) decreases logarithmically; increase of the viscosity ratio results in lower cell deformation. The erythrocyte width S, which exists in the shear plane, is practically invariant in time, flow rate, and viscosity ratio and corresponds to a real cell thickness of about 2.5μm at physiological osmolarity (300mO) and 3.4μm at an osmolarity of 217 mO. The erythrocyte inclination decreases as the flow rate increases or as the surrounding fluid viscosity decreases, owing to the increased inner rotational flow which tends to align the cell toward the flow direction. The ektacytometry deformation of swollen cells increases logarithmically with the shear stress but with a slower slope than that for normal cells owing mainly to the higher orientation of the more swollen cells. As the cell swelling increases, the tank-treading period decreases owing to the higher thickness of the actual cell which overcomes the opposite action of the reduced shape-memory effects (i.e., the more spherical-like erythrocyte's reference shape of shearing resistance). The local area incompressibility tensions from the lipid bilayer increase with the cell swelling and cause a higher cytoskeleton prestress; this increased prestress results in smaller, but still measurable, local area changes on the spectrin skeleton of the more swollen erythrocytes. Our work provides insight on

  7. Is Peroxiredoxin II's peroxidase activity strongly inhibited in human erythrocytes?

    PubMed

    Benfeitas, Rui; Selvaggio, Gianluca; Antunes, Fernando; Coelho, Pedro; Salvador, Armindo

    2014-10-01

    H2O2 elimination in human erythrocytes is mainly carried out by catalase (Cat), glutathione peroxidase (GPx1) and the more recently discovered peroxiredoxin 2 (Prx2). However, the contribution of Prx2 to H2O2 consumption is still unclear. Prx2's high reactivity with H2O2 (kPrx2=10×10(7) M(-1)s(-1), kCat =7×10(7) M(-1)s(-1), kGPx1 =4×10(7) M(-1)s(-1)) and high abundance ([Prx2]= 570µM, [Cat]= 32µM, [GPx1]= 1µM) suggest that under low H2O2 supply rates it should consume >99% of the H2O2. However, extensive evidence indicates that in intact erythrocytes Prx2 contributes no more than Cat to H2O2 consumption. In order for this to be attained, Prx2's effective rate constant with H2O2would have to be just ~10(5) M(-1)s(-1), much lower than that determined in multiple experiments with the purified proteins. Nevertheless, nearly all Prx2 is oxidized within 1min of exposing erythrocytes to a H2O2 bolus, which is inconsistent with an irreversible inhibition. A mathematical model of the H2O2 metabolism in human erythrocytes [Benfeitas et al. (2014) Free Radic. Biol. Med.] where Prx2 either has a low kPrx2 or is subject to a strong (>99%) but readily reversible inhibition achieves quantitative agreement with detailed experimental observations of the responses of the redox status of Prx2 in human erythrocytes and suggests functional advantages of this design (see companion abstract). By contrast, a variant where Prx2 is fully active with kPrx2=10(8) M(-1)s(-1) shows important qualitative discrepancies. Altogether, these results suggest that Prx2's peroxidase activity is strongly inhibited in human erythrocytes. We acknowledge fellowship SFRH/BD/51199/2010, grants PEst-C/SAU/LA0001/2013-2014, PEst-OE/QUI/UI0612/2013, PEst-OE/QUI/UI0313/2014, and FCOMP-01-0124-FEDER-020978 (PTDC/QUI-BIQ/119657/2010) co-financed by FEDER through the COMPETE program and by FCT.

  8. A simple protocol for platelet-mediated clumping of Plasmodium falciparum-infected erythrocytes in a resource poor setting.

    PubMed

    Tembo, Dumizulu L; Montgomery, Jacqui; Craig, Alister G; Wassmer, Samuel C

    2013-01-01

    P. falciparum causes the majority of severe malarial infections. The pathophysiological mechanisms underlying cerebral malaria (CM) are not fully understood and several hypotheses have been put forward, including mechanical obstruction of microvessels by P. falciparum-parasitized red blood cells (pRBC). Indeed, during the intra-erythrocytic stage of its life cycle, P. falciparum has the unique ability to modify the surface of the infected erythrocyte by exporting surface antigens with varying adhesive properties onto the RBC membrane. This allows the sequestration of pRBC in multiple tissues and organs by adhesion to endothelial cells lining the microvasculature of post-capillary venules (1). By doing so, the mature forms of the parasite avoid splenic clearance of the deformed infected erythrocytes (2) and restrict their environment to a more favorable low oxygen pressure (3). As a consequence of this sequestration, it is only immature asexual parasites and gametocytes that can be detected in peripheral blood. Cytoadherence and sequestration of mature pRBC to the numerous host receptors expressed on microvascular beds occurs in severe and uncomplicated disease. However, several lines of evidence suggest that only specific adhesive phenotypes are likely to be associated with severe pathological outcomes of malaria. One example of such specific host-parasite interactions has been demonstrated in vitro, where the ability of intercellular adhesion molecule-1 to support binding of pRBC with particular adhesive properties has been linked to development of cerebral malaria (4,5). The placenta has also been recognized as a site of preferential pRBC accumulation in malaria-infected pregnant women, with chondrotin sulphate A expressed on syncytiotrophoblasts that line the placental intervillous space as the main receptor (6). Rosetting of pRBC to uninfected erythrocytes via the complement receptor 1 (CD35)(7,8) has also been associated with severe disease (9). One of the

  9. A simple protocol for platelet-mediated clumping of Plasmodium falciparum-infected erythrocytes in a resource poor setting.

    PubMed

    Tembo, Dumizulu L; Montgomery, Jacqui; Craig, Alister G; Wassmer, Samuel C

    2013-01-01

    P. falciparum causes the majority of severe malarial infections. The pathophysiological mechanisms underlying cerebral malaria (CM) are not fully understood and several hypotheses have been put forward, including mechanical obstruction of microvessels by P. falciparum-parasitized red blood cells (pRBC). Indeed, during the intra-erythrocytic stage of its life cycle, P. falciparum has the unique ability to modify the surface of the infected erythrocyte by exporting surface antigens with varying adhesive properties onto the RBC membrane. This allows the sequestration of pRBC in multiple tissues and organs by adhesion to endothelial cells lining the microvasculature of post-capillary venules (1). By doing so, the mature forms of the parasite avoid splenic clearance of the deformed infected erythrocytes (2) and restrict their environment to a more favorable low oxygen pressure (3). As a consequence of this sequestration, it is only immature asexual parasites and gametocytes that can be detected in peripheral blood. Cytoadherence and sequestration of mature pRBC to the numerous host receptors expressed on microvascular beds occurs in severe and uncomplicated disease. However, several lines of evidence suggest that only specific adhesive phenotypes are likely to be associated with severe pathological outcomes of malaria. One example of such specific host-parasite interactions has been demonstrated in vitro, where the ability of intercellular adhesion molecule-1 to support binding of pRBC with particular adhesive properties has been linked to development of cerebral malaria (4,5). The placenta has also been recognized as a site of preferential pRBC accumulation in malaria-infected pregnant women, with chondrotin sulphate A expressed on syncytiotrophoblasts that line the placental intervillous space as the main receptor (6). Rosetting of pRBC to uninfected erythrocytes via the complement receptor 1 (CD35)(7,8) has also been associated with severe disease (9). One of the

  10. The integrated phenotype.

    PubMed

    Murren, Courtney J

    2012-07-01

    Proper functioning of complex phenotypes requires that multiple traits work together. Examination of relationships among traits within and between complex characters and how they interact to function as a whole organism is critical to advancing our understanding of evolutionary developmental plasticity. Phenotypic integration refers to the relationships among multiple characters of a complex phenotype, and their relationships with other functional units (modules) in an organism. In this review, I summarize a brief history of the concept of phenotypic integration in plant and animal biology. Following an introduction of concepts, including modularity, I use an empirical case-study approach to highlight recent advance in clarifying the developmental and genomic basis of integration. I end by highlighting some novel approaches to genomic and epigenetic perturbations that offer promise in further addressing the role of phenotypic integration in evolutionary diversification. In the age of the phenotype, studies that examine the genomic and developmental changes in relationships of traits across environments will shape the next chapter in our quest for understanding the evolution of complex characters.

  11. Heat transport in laminar flow of erythrocyte suspensions.

    PubMed

    Ahuja, A S

    1975-07-01

    Measurements of thermal conductivity were made in laminar flow of dog and turkey erythrocyte suspensions in a stainless stell tube of about 1 mm ID. These measurements were independent of the shear rate, showing that the red cell motion relative to plasma in flowing blood had no effect on the heat transfer. Measurements of thermal conductivity were further made in suspensions of polystyrene spheres of 100 mum and were found to be dependent upon the shear rate. The Graetz solution corresponding to uniform wall temperature was used for determining the value of thermal conductivity in an apparatus calibrated with tap water. The overall accuracy of the results is within 10%. A model based on the particle rotation with the entrained fluid is proposed. It is pointed out that the diffusion of platelets, red cells, and possibly plasma proteins (such as fibrinogen) will be augmented if they happen to be in the hydrodynamic field of rotating erythrocytes. PMID:1150598

  12. Effects of ascorbate fatty ester derivatives on erythrocyte membrane lipoperoxidation.

    PubMed

    Spengler, M I; Rasia, M; Palma, S; Allemandi, D

    2011-01-01

    6-O-alkyl ascorbic acid esters (ASC(n)) are amphiphilic molecules that behave as surfactants in aqueous solution. ASC(n) have shown some physical and rheological properties that suggest a potential utility as drug carriers. The present paper aims to evaluate the effect of ASC(n) on erythrocyte properties in order to get information regarding the relationship between osmotic fragility, erythrocyte deformability and membrane lipoperoxidation process. The assays were performed at the following concentrations: the critical micelar concentration (CMC), producing 10% hemolysis (CH(10)) and producing 50% hemolysis (CH(50)). We observed that ASC(n) (ASC(8), ASC(10) and ASC(12)), at concentration nearby CMC, neither affected cell deformability nor produced lipoperoxidation. Nevertheless, at higher concentrations (CH(10) and CH(50)), the RBCs incubated with ASC(n) were affected by a significant and progressive loss of deformability, simultaneously with an increase of osmotic fragility and membrane lipoperoxidation.

  13. Human erythrocytes as nanoparticle carriers for magnetic particle imaging.

    PubMed

    Markov, D E; Boeve, H; Gleich, B; Borgert, J; Antonelli, A; Sfara, C; Magnani, M

    2010-11-01

    The potential of red blood cells (RBCs) loaded with iron oxide nanoparticles as a tracer material for magnetic particle imaging (MPI) has been investigated. MPI is an emerging, quantitative medical imaging modality which holds promise in terms of sensitivity in combination with spatial and temporal resolution. Steady-state and dynamic magnetization measurements, supported by semi-empirical modeling, were employed to analyze the MPI signal generation using RBCs as novel biomimetic constructs. Since the superparamagnetic iron oxide (SPIO) bulk material that is used in this study contains nanoparticles with different sizes, it is suggested that during the RBC loading procedure, a preferential entrapment of nanoparticles with hydrodynamic diameter ≤60 nm occurs by size-selection through the erythrocyte membrane pores. This affects the MPI signal of an erythrocyte-based tracer, compared to bulk. The reduced signal is counterbalanced by a higher in vivo stability of the SPIO-loaded RBCs constructs for MPI applications.

  14. Cell Electrofusion in Centrifuged Erythrocyte Pellets Assessed by Dielectric Spectroscopy.

    PubMed

    Asami, Koji

    2016-04-01

    We have characterized cell electrofusion in cell pellets by dielectric spectroscopy. Cell pellets were formed from horse erythrocyte suspensions by centrifugation and were subjected to intense AC pulses. The dielectric spectra of the pellets were measured over a frequency range of 10 Hz to 10 MHz. The application of AC pulses caused low-frequency (LF) dielectric relaxation below about 100 kHz. The LF dielectric relaxation was markedly affected not only by pretreatment of cells at 50 °C, which disrupts the spectrin network of erythrocytes, but also by the parameters of the AC pulses (frequency of the sine wave and repeat count of the pulses). The occurrence of the LF dielectric relaxation was qualitatively accounted for by modeling fusion products in the pellet by prolate spheroidal cells whose long axes run parallel to the applied electric field.

  15. Recent advancements in erythrocytes, platelets, and albumin as delivery systems

    PubMed Central

    Xu, Peipei; Wang, Ruju; Wang, Xiaohui; Ouyang, Jian

    2016-01-01

    In the past few years, nanomaterial-based drug delivery systems have been applied to enhance the efficacy of therapeutics and to alleviate negative effects through the controlled delivery of targeting and releasing agents. However, few drug carriers can achieve high targeting efficacy, even when targeting modalities and surface markers are introduced. Immunological problems have also limited their wide applications. Biological drug delivery systems, such as erythrocytes, platelets, and albumin, have been extensively investigated because of their unique properties. In this review, erythrocytes, platelets, and albumin are described as efficient drug delivery systems. Their properties, applications, advantages, and limitations in disease treatment are explained. This review confirms that these systems can be used to facilitate a specific, biocompatible, and smart drug delivery. PMID:27274282

  16. Heat transport in laminar flow of erythrocyte suspensions.

    PubMed

    Ahuja, A S

    1975-07-01

    Measurements of thermal conductivity were made in laminar flow of dog and turkey erythrocyte suspensions in a stainless stell tube of about 1 mm ID. These measurements were independent of the shear rate, showing that the red cell motion relative to plasma in flowing blood had no effect on the heat transfer. Measurements of thermal conductivity were further made in suspensions of polystyrene spheres of 100 mum and were found to be dependent upon the shear rate. The Graetz solution corresponding to uniform wall temperature was used for determining the value of thermal conductivity in an apparatus calibrated with tap water. The overall accuracy of the results is within 10%. A model based on the particle rotation with the entrained fluid is proposed. It is pointed out that the diffusion of platelets, red cells, and possibly plasma proteins (such as fibrinogen) will be augmented if they happen to be in the hydrodynamic field of rotating erythrocytes.

  17. Human erythrocytes as nanoparticle carriers for magnetic particle imaging.

    PubMed

    Markov, D E; Boeve, H; Gleich, B; Borgert, J; Antonelli, A; Sfara, C; Magnani, M

    2010-11-01

    The potential of red blood cells (RBCs) loaded with iron oxide nanoparticles as a tracer material for magnetic particle imaging (MPI) has been investigated. MPI is an emerging, quantitative medical imaging modality which holds promise in terms of sensitivity in combination with spatial and temporal resolution. Steady-state and dynamic magnetization measurements, supported by semi-empirical modeling, were employed to analyze the MPI signal generation using RBCs as novel biomimetic constructs. Since the superparamagnetic iron oxide (SPIO) bulk material that is used in this study contains nanoparticles with different sizes, it is suggested that during the RBC loading procedure, a preferential entrapment of nanoparticles with hydrodynamic diameter ≤60 nm occurs by size-selection through the erythrocyte membrane pores. This affects the MPI signal of an erythrocyte-based tracer, compared to bulk. The reduced signal is counterbalanced by a higher in vivo stability of the SPIO-loaded RBCs constructs for MPI applications. PMID:20959685

  18. Recent advancements in erythrocytes, platelets, and albumin as delivery systems.

    PubMed

    Xu, Peipei; Wang, Ruju; Wang, Xiaohui; Ouyang, Jian

    2016-01-01

    In the past few years, nanomaterial-based drug delivery systems have been applied to enhance the efficacy of therapeutics and to alleviate negative effects through the controlled delivery of targeting and releasing agents. However, few drug carriers can achieve high targeting efficacy, even when targeting modalities and surface markers are introduced. Immunological problems have also limited their wide applications. Biological drug delivery systems, such as erythrocytes, platelets, and albumin, have been extensively investigated because of their unique properties. In this review, erythrocytes, platelets, and albumin are described as efficient drug delivery systems. Their properties, applications, advantages, and limitations in disease treatment are explained. This review confirms that these systems can be used to facilitate a specific, biocompatible, and smart drug delivery.

  19. The Behavioural Phenotype of Angelman Syndrome

    ERIC Educational Resources Information Center

    Horsler, K.; Oliver, C.

    2006-01-01

    Background: The purpose of this review is to examine the notion of a behavioural phenotype for Angelman syndrome and identify methodological and conceptual influences on the accepted presentation. Methods: Studies examining the behavioural characteristics associated with Angelman syndrome are reviewed and methodology is described. Results:…

  20. The Relativity of Genotypes and Phenotypes.

    ERIC Educational Resources Information Center

    Willie, Charles Vert

    1995-01-01

    Asserts that Herrnstein and Murray's "The Bell Curve" (1994) is an attempt to influence and control public discourse about public policy and inequality. It examines four of the book's flaws in classification, analyses, research, and its failure to recognize intelligence as having both genotypic and phenotypic manifestations. (GR)

  1. Venom Evolution: Gene Loss Shapes Phenotypic Adaptation.

    PubMed

    Casewell, Nicholas R

    2016-09-26

    Snake venoms are variable protein mixtures with a multitude of bioactivities. New work shows, surprisingly, that it is the loss of toxin-encoding genes that strongly influences venom function in rattlesnakes, highlighting how gene loss can underpin adaptive phenotypic change. PMID:27676304

  2. Erythrocyte membrane stability to hydrogen peroxide is decreased in Alzheimer disease.

    PubMed

    Gilca, Marilena; Lixandru, Daniela; Gaman, Laura; Vîrgolici, Bogdana; Atanasiu, Valeriu; Stoian, Irina

    2014-01-01

    The brain and erythrocytes have similar susceptibility toward free radicals. Therefore, erythrocyte abnormalities might indicate the progression of the oxidative damage in Alzheimer disease (AD). The aim of this study was to investigate erythrocyte membrane stability and plasma antioxidant status in AD. Fasting blood samples (from 17 patients with AD and 14 healthy controls) were obtained and erythrocyte membrane stability against hydrogen peroxide and 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), serum Trolox equivalent antioxidant capacity (TEAC), residual antioxidant activity or gap (GAP), erythrocyte catalase activity (CAT), erythrocyte superoxide dismutase (SOD) activity, erythrocyte nonproteic thiols, and total plasma thiols were determined. A significant decrease in erythrocyte membrane stability to hydrogen peroxide was found in AD patients when compared with controls (P<0.05). On the contrary, CAT activity (P<0.0001) and total plasma thiols (P<0.05) were increased in patients with AD compared with controls. Our results indicate that the most satisfactory measurement of the oxidative stress level in the blood of patients with AD is the erythrocyte membrane stability to hydrogen peroxide. Reduced erythrocyte membrane stability may be further evaluated as a potential peripheral marker for oxidative damage in AD.

  3. Bilayer/cytoskeleton interactions in lipid-symmetric erythrocytes assessed by a photoactivable phospholipid analogue

    SciTech Connect

    Pradhan, D.; Schlegel, R.A. ); Williamson, P. )

    1991-08-06

    Two mechanisms have been proposed for maintenance of transbilayer phospholipid asymmetry in the erythrocyte plasma membrane, one involving specific interactions between the aminophospholipids of the inner leaflet of the bilayer and the cytoskeleton, particularly spectrin, and the other involving the aminophospholipid translocase. If the former mechanism is correct, then erythrocytes which have lost their asymmetric distribution of phospholipids should display altered bilayer/cytoskeleton interactions. To test this possibility, normal erythrocytes, erythrocytes from patients with chronic myelogenous leukemia or sickle disease, and lipid-symmetric and -asymmetric erythrocyte ghosts were labeled with the radioactive photoactivable analogue of phosphatidylethanolamine, 2-(2-azido-4-nitrobenzoyl)-1-acyl-sn-glycero-3-phospho({sup 14}C) ethanolamine (({sup 14}C)AzPE), previously shown to label cytoskeletal proteins from the bilayer. The labeling pattern of cytoskeletal proteins in pathologic erythrocytes and lipid-asymmetric erythrocyte ghosts was indistinguishable from normal erythrocytes, indicating that the probe detects no differences in bilayer/cytoskeleton interactions in these cells. In contrast, in lipid-symmetric erythrocyte ghosts, labeling of bands 4.1 and 4.2 and actin, and to a lesser extent ankyrin, by ({sup 14}C)AzPE was considerably reduced. Significantly, however, labeling of spectrin was unaltered in the lipid-symmetric cells. These results do not support a model in which spectrin is involved in the maintenance of an asymmetric distribution of phospholipids in erythrocytes.

  4. Circulating IgM Requires Plasma Membrane Disruption to Bind Apoptotic and Non-Apoptotic Nucleated Cells and Erythrocytes

    PubMed Central

    Hesketh, Emily E.; Dransfield, Ian; Kluth, David C.; Hughes, Jeremy

    2015-01-01

    Autoimmunity is associated with defective phagocytic clearance of apoptotic cells. IgM deficient mice exhibit an autoimmune phenotype consistent with a role for circulating IgM antibodies in apoptotic cell clearance. We have extensively characterised IgM binding to non-apoptotic and apoptotic mouse thymocytes and human Jurkat cells using flow cytometry, confocal imaging and electron microscopy. We demonstrate strong specific IgM binding to a subset of Annexin-V (AnnV)+PI (Propidium Iodide)+ apoptotic cells with disrupted cell membranes. Electron microscopy studies indicated that IgM+AnnV+PI+ apoptotic cells exhibited morphologically advanced apoptosis with marked plasma membrane disruption compared to IgM-AnnV+PI+ apoptotic cells, suggesting that access to intracellular epitopes is required for IgM to bind. Strong and comparable binding of IgM to permeabilised non-apoptotic and apoptotic cells suggests that IgM bound epitopes are 'apoptosis independent' such that IgM may bind any cell with profound disruption of cell plasma membrane integrity. In addition, permeabilised erythrocytes exhibited significant IgM binding thus supporting the importance of cell membrane epitopes. These data suggest that IgM may recognize and tag damaged nucleated cells or erythrocytes that exhibit significant cell membrane disruption. The role of IgM in vivo in conditions characterized by severe cell damage such as ischemic injury, sepsis and thrombotic microangiopathies merits further exploration. PMID:26121639

  5. Circulating IgM Requires Plasma Membrane Disruption to Bind Apoptotic and Non-Apoptotic Nucleated Cells and Erythrocytes.

    PubMed

    Hesketh, Emily E; Dransfield, Ian; Kluth, David C; Hughes, Jeremy

    2015-01-01

    Autoimmunity is associated with defective phagocytic clearance of apoptotic cells. IgM deficient mice exhibit an autoimmune phenotype consistent with a role for circulating IgM antibodies in apoptotic cell clearance. We have extensively characterised IgM binding to non-apoptotic and apoptotic mouse thymocytes and human Jurkat cells using flow cytometry, confocal imaging and electron microscopy. We demonstrate strong specific IgM binding to a subset of Annexin-V (AnnV)+PI (Propidium Iodide)+ apoptotic cells with disrupted cell membranes. Electron microscopy studies indicated that IgM+AnnV+PI+ apoptotic cells exhibited morphologically advanced apoptosis with marked plasma membrane disruption compared to IgM-AnnV+PI+ apoptotic cells, suggesting that access to intracellular epitopes is required for IgM to bind. Strong and comparable binding of IgM to permeabilised non-apoptotic and apoptotic cells suggests that IgM bound epitopes are 'apoptosis independent' such that IgM may bind any cell with profound disruption of cell plasma membrane integrity. In addition, permeabilised erythrocytes exhibited significant IgM binding thus supporting the importance of cell membrane epitopes. These data suggest that IgM may recognize and tag damaged nucleated cells or erythrocytes that exhibit significant cell membrane disruption. The role of IgM in vivo in conditions characterized by severe cell damage such as ischemic injury, sepsis and thrombotic microangiopathies merits further exploration.

  6. Structural specificity of serotonin effect on human erythrocyte fragility.

    PubMed

    Gilboa-Garber, N; Kirstein-Segal, R

    1998-08-01

    Serotonin, a neurotransmitter and vasoconstrictor, affects various cell properties. We have analyzed the importance of its structural components for its extensive effect on human erythrocyte fragility, using its O- and N-linked derivatives and related compounds. The results presented in this communication indicate that the amino group, free of adjacent negative charges, and the hydroxyl group are indispensable for the serotonin-induced increase in red blood cell fragility. PMID:9758719

  7. Structural alterations of erythrocyte membrane components induced by exhaustive exercise.

    PubMed

    Brzeszczynska, Joanna; Pieniazek, Anna; Gwozdzinski, Lukasz; Gwozdzinski, Krzysztof; Jegier, Anna

    2008-12-01

    Physical exercise was used as a model of the physiological modulator of free radical production to examine the effects of exercise-induced oxidative modifications on the physico-biochemical properties of erythrocyte membrane. The aim of our work was to investigate conformational changes of erythrocyte membrane proteins, membrane fluidity, and membrane susceptibility to disintegration. Venous blood was taken before, immediately after, and 1 h after an exhaustive incremental cycling test (30 W.min-1 ramp), performed by 11 healthy untrained males on balanced diets (mean age, 22 +/- 2 years; mean body mass index, 25 +/- 4.5 kg.m-2). In response to this exercise, individual maximum heart rate was 195 +/- 12 beats.min-1 and maximum wattage was 292 +/- 27 W. Electron paramagnetic resonance spectroscopy was used to investigate alterations in membrane proteins and membrane dynamics, and to measure production of radical species. The reducing potential of plasma (RPP) was measured using the reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the ferric-reducing ability of plasma. Exercise induced decreases in erythrocyte membrane fluidity in the polar region (p < 0.0001) and alterations in the conformational state of membrane proteins (p < 0.05). An increase in RPP was observed immediately after exercise (p < 0.001), with a further increase 1 h postexercise (p < 0.0001). Supporting measurements of lipid peroxidation showed an increase in thiobarbituric acid reactive substances immediately after exercise (p < 0.05) and at 1 h of recovery (p < 0.001); however, free radicals were not detected. Results indicate the existence of early postexercise mild oxidative stress after single-exercise performance, which induced structural changes in erythrocyte membrane components (protein aggregation) and in the membrane organization (lipids rigidization) that followed lipid peroxidation but did not lead to cellular hemolysis.

  8. Sodium and potassium transport in trout (Salmo gairdneri) erythrocytes.

    PubMed Central

    Bourne, P K; Cossins, A R

    1984-01-01

    The principal pathways of Na+ and K+ transport in trout erythrocytes have been characterized. Approximately 50% of K+ influx in steady-state erythrocytes was inhibited by ouabain (1 mM) and 46% by furosemide (1 mM). Furosemide-sensitive K+ influx was a saturable function of external K+ concentration with a Km of 25 mM. This flux component was also inhibited by SITS (4-acetamido-4'-isothiocyanatostilbene-2'2-disulphonate) (concentration required for 50% inhibition, I50 = 7.6 X 10(-6)M) and by the removal of external Cl-. An increase in cell volume stimulated furosemide-sensitive K+ influx and cell shrinkage inhibited this flux. K+ efflux was mainly furosemide-sensitive (64% of total). This pathway was unaffected by variations in extracellular K+ concentration and is therefore not exchange diffusion. However, it was affected by variations in cell volume in a similar way to the furosemide-sensitive K+ influx. Na+ influx was only slightly sensitive to furosemide (13% of total) but this component was very sensitive to changes in cell volume; decreased cell volume increased Na+ influx whilst increased cell volume inhibited Na+ influx. Furosemide-sensitive K+ influx was unaffected by variations in external Na+ concentration. Similarly, furosemide-sensitive Na+ influx was unaffected by variations in external K+ concentration. This indicates that the passive influxes of Na+ and K+ were not coupled, in contrast to the situation in avian erythrocytes. The opposite effects of cell volume upon passive Na+ and K+ fluxes are in good agreement with the net movements of these cations during volume regulation in erythrocytes of the flounder (Cala, 1977) and the toadfish (Lauf, 1982). PMID:6707960

  9. Are polyphosphoinositides associated with glycophorin in human erythrocyte membranes?

    PubMed

    Shukla, S D; Coleman, R; Finean, J B; Michell, R H

    1979-05-01

    Glycophorin prepared by a lithium di-iodosalicylate-extraction/phenol-partition method was rich in polyphosphoinositides (phosphatidyl-myo-inositol 4-phosphate and phosphatidyl-myo-inositol 4,5-bisphosphate), but glycophorin extracted by Triton X-100 showed no such enrichment. The enrichment observed in the former preparations appeared not to be caused by pre-existing association between glycophorin and polyphosphoinositides in the human erythrocyte membrane, but to be largely a consequence of the preparative procedures.

  10. Dielectric relaxations on erythrocyte membrane as revealed by spectrin denaturation.

    PubMed

    Ivanov, I T; Paarvanova, B

    2016-08-01

    We studied the effect of spectrin denaturation at 49.5°C (TA) on the dielectric relaxations and related changes in the complex impedance, Z*, complex capacitance, C*, and dielectric loss curve of suspensions containing human erythrocytes, erythrocyte ghost membranes (EMs) and Triton-X-100 residues of EMs. The loss curve prior to, minus the loss curve after TA, resulted in a bell-shaped peak at 1.5MHz. The changes in the real and imaginary components of Z* and C* at TA, i.e., ΔZre, ΔZim, ΔCre and ΔCim, calculated in the same way, strongly varied with frequency. Between 1.0 and 12MHz the -ΔZim vs ΔZre, and ΔCim vs ΔCre plots depicted semicircles with critical frequencies, fcr, at 2.5MHz expressing recently reported relaxation of spectrin dipoles. Between 0.02 and 1.0MHz the -ΔZim vs ΔZre plot exhibited another relaxation whose fcr mirrored that of beta relaxation. This relaxation was absent on Triton-X-shells, while on erythrocytes and EMs it was inhibited by selective dissociation of either attachment sites between spectrin and bilayer. Considering above findings and inaccessibility of cytosole to outside field at such frequencies, the latter relaxation was assumed originating from a piezoelectric effect on the highly deformable spectrin filaments.

  11. Micronucleated erythrocytes in newborn rats exposed to raltegravir placental transfer.

    PubMed

    Torres-Mendoza, Blanca Miriam; Coronado-Medina, Damharis Elizabeth; Gómez-Meda, Belinda Claudia; Vázquez-Valls, Eduardo; Zamora-Perez, Ana Lourdes; Lemus-Varela, María de Lourdes; Zúñiga-González, Guillermo Moisés

    2014-01-01

    The use of raltegravir in treating HIV/AIDS has been proposed due to its effectiveness in suppressing high loads of HIV RNA in pregnant women, thus preventing infection of the fetus. However, administration of raltegravir during pregnancy produces a compound which is transferred to high concentrations to the offspring. The objective of this study is to evaluate the transplacental genotoxic effect of raltegravir in newborn rats. We evaluated the number of micronucleated erythrocytes (MNE), micronucleated polychromatic erythrocytes (MNPCE), and polychromatic erythrocytes (PCE) in the peripheral blood samples of the offspring of Wistar rats treated 6 days before birth with oral administration of raltegravir. The animals were randomly assigned to five groups as follows: raltegravir at doses of 15, 30, or 60 mg/day, cyclophosphamide 10 mg/kg (positive control), or 0.5 ml of sterile water (negative control). In addition, the effect of these drugs on the weight and height of newborns was assessed. There were no differences in the number of MNE, MNPCE, and PCE, and a slight decrease in the weight and height was observed in the offspring of the rat mothers treated with raltegravir. Genotoxicity studies are required in pregnant women to determine the risk of using raltegravir to the fetuses.

  12. Drug-loaded erythrocytes: on the road toward marketing approval.

    PubMed

    Bourgeaux, Vanessa; Lanao, José M; Bax, Bridget E; Godfrin, Yann

    2016-01-01

    Erythrocyte drug encapsulation is one of the most promising therapeutic alternative approaches for the administration of toxic or rapidly cleared drugs. Drug-loaded erythrocytes can operate through one of the three main mechanisms of action: extension of circulation half-life (bioreactor), slow drug release, or specific organ targeting. Although the clinical development of erythrocyte carriers is confronted with regulatory and development process challenges, industrial development is expanding. The manufacture of this type of product can be either centralized or bedside based, and different procedures are employed for the encapsulation of therapeutic agents. The major challenges for successful industrialization include production scalability, process validation, and quality control of the released therapeutic agents. Advantages and drawbacks of the different manufacturing processes as well as success key points of clinical development are discussed. Several entrapment technologies based on osmotic methods have been industrialized. Companies have already achieved many of the critical clinical stages, thus providing the opportunity in the future to cover a wide range of diseases for which effective therapies are not currently available. PMID:26929599

  13. Micronucleated Erythrocytes in Newborn Rats Exposed to Raltegravir Placental Transfer

    PubMed Central

    Torres-Mendoza, Blanca Miriam; Coronado-Medina, Damharis Elizabeth; Vázquez-Valls, Eduardo; Zamora-Perez, Ana Lourdes; Lemus-Varela, María de Lourdes

    2014-01-01

    The use of raltegravir in treating HIV/AIDS has been proposed due to its effectiveness in suppressing high loads of HIV RNA in pregnant women, thus preventing infection of the fetus. However, administration of raltegravir during pregnancy produces a compound which is transferred to high concentrations to the offspring. The objective of this study is to evaluate the transplacental genotoxic effect of raltegravir in newborn rats. We evaluated the number of micronucleated erythrocytes (MNE), micronucleated polychromatic erythrocytes (MNPCE), and polychromatic erythrocytes (PCE) in the peripheral blood samples of the offspring of Wistar rats treated 6 days before birth with oral administration of raltegravir. The animals were randomly assigned to five groups as follows: raltegravir at doses of 15, 30, or 60 mg/day, cyclophosphamide 10 mg/kg (positive control), or 0.5 ml of sterile water (negative control). In addition, the effect of these drugs on the weight and height of newborns was assessed. There were no differences in the number of MNE, MNPCE, and PCE, and a slight decrease in the weight and height was observed in the offspring of the rat mothers treated with raltegravir. Genotoxicity studies are required in pregnant women to determine the risk of using raltegravir to the fetuses. PMID:24977162

  14. Erythrocyte deformability - A partner of the inflammatory response.

    PubMed

    Silva-Herdade, Ana Santos; Andolina, Giulia; Faggio, Caterina; Calado, Ângelo; Saldanha, Carlota

    2016-09-01

    We aim to establish an in vivo animal model of acute inflammation using PAF (platelet activating factor) as inflammatory agent and to study the erythrocyte deformability changes induced by the inflammatory response. Counting the number of rolling and adherent neutrophils to endothelium after 2, 4 and 6h of intrascrotal injection of PAF we showed the induction of an inflammatory state. Blood samples are collected in order to measure the erythrocyte deformability and to quantify NO efflux from the red blood cells (RBCs). The results show an increased number of rolling and adherent neutrophils after 2h and 4h of inflammation as well as decreased values of erythrocyte deformability in the same time-points. This result is in line with the need of a low blood viscosity to the recruitment process that will improve leukocyte migration towards the endothelial wall. NO efflux from RBCs is also affected by the inflammatory response at the first hours of inflammation. This animal model demonstrates in vivo the association between an acute inflammatory response and the rheological properties of the blood, namely the RBCs deformability. For those reasons we consider this as an adequate model to study acute inflammatory responses as well as hemorheological parameters. PMID:27142964

  15. 7Li NMR study of normal human erythrocytes

    NASA Astrophysics Data System (ADS)

    Pettegrew, J. W.; Post, J. F. M.; Panchalingam, K.; Withers, G.; Woessner, D. E.

    The biological action of lithium is of great interest because of the therapeutic efficacy of the cation in manic-depressive illness. To investigate possible molecular interactions of lithium, 7Li NMR studies were conducted on normal human erythrocytes which had been incubated with lithium chloride. The uptake of lithium ions was followed by 7Li NMR, using a dysprosium, tripolyphosphate shift reagent. Lithium uptake followed single-exponential kinetics with a time constant of 14.7 h. The intracellular lithium relaxation times were T 1 ⋍ 5 s and T 2 ⋍ 0.15 s, which implies a lengthening of the lithium correlation time. It was found that lithium does not interact significantly with hemoglobin, the erythrocyte membrane, or artificial phospholipid membranes. Based on measurements of lithium T1 and T2 in concentrated agar gels, the large difference between T1 and T2 for intracellular lithium ions may be due to diffusion of the hydrated lithium ion through heterogeneous electrostatic field gradients created by the erythrocyte membrane-associated cytoskeletal network. Lithium binding to the membrane-associated cytoskeleton, however, cannot be ruled out. Because of the large differences between T1 and T2 of intracellular lithium ions, 1Li NMR may be a sensitive and promising noninvasive method to probe the intracellular environment.

  16. Biorheological action of Ascaris lumbricoides larvae on human erythrocytes.

    PubMed

    de León, Patricia Ponce; Del Balzo, Gonzalo; Riquelme, Bibiana

    2013-03-01

    Previous studies have shown that A. lumbricoides extracts capture sialic acid (SA) from human red blood cells (RBC). The aim of this work was to study hemorheological alterations in vitro caused by parasite larvae. The biorheological action of three larva concentrates of first and second larval stage on group O erythrocytes was analyzed by incubating the erythrocyte packed together with an equal volume of larvae (treated RBC) and PBS (control RBC). Distribution and parameters of aggregation (digital image analysis), aggregation kinetics (erythroaggregameter), and viscoelasticity (erythrodeformeter) were measured. The digital image analysis showed that all the larvae diminished the isolated cells percentage and increased the size of the formed aggregates. The aggregate formation velocity was lower in the treated than in the control. The deformability index (ID) values of treated RBC did not present variations with respect to those of the control, but a decrease in the erythrocyte elastic modulus (μ(m)) and membrane surface viscosity (η(m)) values was observed, indicating that the larvae not only induced a diminution in the membrane surface viscosity of RBC but also altered the dynamic viscoelasticity of the membrane. Experiments carried out in vitro support the conclusion that the contact between larvae and RBC produces hemorheological alterations.

  17. Modulation Effects of Curcumin on Erythrocyte Ion-Transporter Activity

    PubMed Central

    Singh, Prabhakar; Rizvi, Syed Ibrahim

    2015-01-01

    Curcumin ((1E,6E)-1,7-Bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione), the yellow biphenolic pigment isolated from turmeric (Curcuma longa), has various medicinal benefits through antioxidation, anti-inflammation, cardiovascular protection, immunomodulation, enhancing of the apoptotic process, and antiangiogenic property. We explored the effects of curcumin in vitro (10−5 M to 10−8 M) and in vivo (340 and 170 mg/kg b.w., oral) on Na+/K+ ATPase (NKA), Na+/H+ exchanger (NHE) activity, and membrane lipid hydroperoxides (ROOH) in control and experimental oxidative stress erythrocytes of Wistar rats. As a result, we found that curcumin potently modulated the membrane transporters activity with protecting membrane lipids against hydro-peroxidation in control as well as oxidatively challenged erythrocytes evidenced by stimulation of NKA, downregulation of NHE, and reduction of ROOH in the membrane. The observed results corroborate membrane transporters activity with susceptibility of erythrocyte membrane towards oxidative damage. Results explain the protective mechanism of curcumin against oxidative stress mediated impairment in ions-transporters activity and health beneficial effects. PMID:26421014

  18. Drug-loaded erythrocytes: on the road toward marketing approval.

    PubMed

    Bourgeaux, Vanessa; Lanao, José M; Bax, Bridget E; Godfrin, Yann

    2016-01-01

    Erythrocyte drug encapsulation is one of the most promising therapeutic alternative approaches for the administration of toxic or rapidly cleared drugs. Drug-loaded erythrocytes can operate through one of the three main mechanisms of action: extension of circulation half-life (bioreactor), slow drug release, or specific organ targeting. Although the clinical development of erythrocyte carriers is confronted with regulatory and development process challenges, industrial development is expanding. The manufacture of this type of product can be either centralized or bedside based, and different procedures are employed for the encapsulation of therapeutic agents. The major challenges for successful industrialization include production scalability, process validation, and quality control of the released therapeutic agents. Advantages and drawbacks of the different manufacturing processes as well as success key points of clinical development are discussed. Several entrapment technologies based on osmotic methods have been industrialized. Companies have already achieved many of the critical clinical stages, thus providing the opportunity in the future to cover a wide range of diseases for which effective therapies are not currently available.

  19. Electro-orientation of ellipsoidal erythrocytes. Theory and experiment.

    PubMed Central

    Miller, R D; Jones, T B

    1993-01-01

    The frequency-dependent orientation of human and llama erythrocytes suspended in isotonic solutions and subjected to linearly polarized electric fields is examined. Human erythrocytes may be represented as oblate spheroids (3.9:3.9:1.1 microns) with two distinguishable orientations, while the llama cells are approximated as ellipsoids with three distinct axes (4.0:2.0:1.1 microns). Under appropriate experimental conditions, both orientations of the human cells and all three orientations of the llama cells are observed. A theoretical cell model which accounts for the membrane as a thin confocal layer of ideal capacitance is used to predict the orientational spectra. The predicted spectra compare favorably in frequency range and orientational sequence with experimental data. Estimates for cell internal conductivity and permittivity are obtained by adjusting the values of these important parameters to achieve the closet fit of the theoretical curves to the data. By the use of this method, the internal conductivity of llama erythrocytes is estimated to be 0.26 S/m (+/- 20%), while the effective internal dielectric constant and conductivity of Euglena gracilis are estimated to be 120 (+/- 10%) and 0.43 S/m (+/- 20%), respectively. PMID:8324193

  20. Diet of racing sled dogs affects erythrocyte depression by stress.

    PubMed

    Adkins, T O; Kronfeld, D S

    1982-09-01

    Fourteen racing huskies were matched into pairs then assigned to two diets, a commercial stress diet and an experimental diet. Proportions of protein: fat:carbohydrate on an available energy basis were 23:57:20 in a commercial stress diet and 28:69:3 in an experimental diet. The team participated in the 1979 Iditarod Trail race and was overtaken by an episode of diarrhea. Clinical signs were suggestive of parvovirus infection; high serum titers of parvo antibodies were found after the race. Blood examination showed normal levels of metabolites, electrolytes and enzymes after the race. Erythrocyte counts were depressed significantly during the race, by 15% in dogs fed an experimental diet and by 27% in those fed a commercial stress diet. Erythrocyte parameters have also become depressed during the racing season in middle distance sled dogs fed 28% protein (energy basis) but not 32 or 39%. Depressed red blood cell production has been demonstrated previously in dogs subjected to stress induced experimentally in several ways, and its restoration has been affected by dietary protein. Erythrocyte parameters may be useful indicies of the degree of stress in a dog as well as the adequacy of its protein intake during stress. PMID:17422178

  1. Dielectric relaxations on erythrocyte membrane as revealed by spectrin denaturation.

    PubMed

    Ivanov, I T; Paarvanova, B

    2016-08-01

    We studied the effect of spectrin denaturation at 49.5°C (TA) on the dielectric relaxations and related changes in the complex impedance, Z*, complex capacitance, C*, and dielectric loss curve of suspensions containing human erythrocytes, erythrocyte ghost membranes (EMs) and Triton-X-100 residues of EMs. The loss curve prior to, minus the loss curve after TA, resulted in a bell-shaped peak at 1.5MHz. The changes in the real and imaginary components of Z* and C* at TA, i.e., ΔZre, ΔZim, ΔCre and ΔCim, calculated in the same way, strongly varied with frequency. Between 1.0 and 12MHz the -ΔZim vs ΔZre, and ΔCim vs ΔCre plots depicted semicircles with critical frequencies, fcr, at 2.5MHz expressing recently reported relaxation of spectrin dipoles. Between 0.02 and 1.0MHz the -ΔZim vs ΔZre plot exhibited another relaxation whose fcr mirrored that of beta relaxation. This relaxation was absent on Triton-X-shells, while on erythrocytes and EMs it was inhibited by selective dissociation of either attachment sites between spectrin and bilayer. Considering above findings and inaccessibility of cytosole to outside field at such frequencies, the latter relaxation was assumed originating from a piezoelectric effect on the highly deformable spectrin filaments. PMID:27071054

  2. Disorders in the Morphology and Nanostructure of Erythrocyte Membranes after Long-term Storage of Erythrocyte Suspension: Atomic Force Microscopy Study.

    PubMed

    Moroz, V V; Chernysh, A M; Kozlova, E K; Sergunova, V A; Gudkova, O E; Khoroshilov, S E; Onufrievich, A D; Kostin, A I

    2015-07-01

    Disorders in the erythrocyte morphology and structure of their membranes during long-term storage of erythrocyte suspension (30 days at 4°C) were studied by atomic force microscopy. The morphology and nanostructure of erythrocyte membranes, biochemical parameters, ion exchange parameters, and hemoglobin spectra were recorded. The transformation of erythrocyte morphology and destruction of their membranes were observed throughout the storage period. Irreversible forms of spheroechinocytes and their fragments formed by the end of storage. The concentrations of potassium ions and lactate in solution of the blood preservatiive increased, while pH value decreased. Hemolysis detected by the erythrocyte "leakage" effect was observed starting from days 16-23 of storage.

  3. H-deficient blood groups of Reunion island. II. Differences between Indians (Bombay Phenotype) and whites (Reunion phenotype).

    PubMed

    Le Pendu, J; Gerard, G; Vitrac, D; Juszczak, G; Liberge, G; Rouger, P; Salmon, C; Lambert, F; Dalix, A M; Oriol, R

    1983-05-01

    Two variants of recessive, H-deficient nonsecretor individuals (h/h, se/se) were identified on Reunion Island: (1) H-negative individuals corresponding to the classical Bombay phenotypes (OhO, OhA, OhB, OhAB) who lack completely the H antigen on their red cells; all of them were Indian and had strong anti-H antibodies reacting with normal O and Oh red cells from whites; and (2) H-weak individuals (Oh, Ah, Bh, ABh). This phenotype represented the majority (85%) of the H-deficient phenotypes on Reunion Island, and all of them were white. They had only a weak expression of the H antigen and showed small but detectable amounts of ABH antigens on their red cells. Their anti-H antibodies reacted with normal O erythrocytes, but failed to react with Oh red cells, regardless of the ethnic origin of the donor. They were all from the same geographical area on the Island (Cilaos) and showed homogeneous titers of anti-H antibodies in sera. We propose to call this particular variant of weak H phenotype, belonging to the so-called para-Bombay series, Reunion.

  4. Mediterranean-style diet effect on the structural properties of the erythrocyte cell membrane of hypertensive patients: the Prevencion con Dieta Mediterranea Study.

    PubMed

    Barceló, Francisca; Perona, Javier S; Prades, Jesús; Funari, Sérgio S; Gomez-Gracia, Enrique; Conde, Manuel; Estruch, Ramon; Ruiz-Gutiérrez, Valentina

    2009-11-01

    A currently ongoing randomized trial has revealed that the Mediterranean diet, rich in virgin olive oil or nuts, reduces systolic blood pressure in high-risk cardiovascular patients. Here, we present a structural substudy to assess the effect of a Mediterranean-style diet supplemented with nuts or virgin olive oil on erythrocyte membrane properties in 36 hypertensive participants after 1 year of intervention. Erythrocyte membrane lipid composition, structural properties of reconstituted erythrocyte membranes, and serum concentrations of inflammatory markers are reported. After the intervention, the membrane cholesterol content decreased, whereas that of phospholipids increased in all of the dietary groups; the diminishing cholesterol:phospholipid ratio could be associated with an increase in the membrane fluidity. Moreover, reconstituted membranes from the nuts and virgin olive oil groups showed a higher propensity to form a nonlamellar inverted hexagonal phase structure that was related to an increase in phosphatidylethanolamine lipid class. These data suggest that the Mediterranean-style diet affects the lipid metabolism that is altered in hypertensive patients, influencing the structural membrane properties. The erythrocyte membrane modulation described provides insight in the structural bases underlying the beneficial effect of a Mediterranean-style diet in hypertensive subjects. PMID:19805640

  5. Mediterranean-style diet effect on the structural properties of the erythrocyte cell membrane of hypertensive patients: the Prevencion con Dieta Mediterranea Study.

    PubMed

    Barceló, Francisca; Perona, Javier S; Prades, Jesús; Funari, Sérgio S; Gomez-Gracia, Enrique; Conde, Manuel; Estruch, Ramon; Ruiz-Gutiérrez, Valentina

    2009-11-01

    A currently ongoing randomized trial has revealed that the Mediterranean diet, rich in virgin olive oil or nuts, reduces systolic blood pressure in high-risk cardiovascular patients. Here, we present a structural substudy to assess the effect of a Mediterranean-style diet supplemented with nuts or virgin olive oil on erythrocyte membrane properties in 36 hypertensive participants after 1 year of intervention. Erythrocyte membrane lipid composition, structural properties of reconstituted erythrocyte membranes, and serum concentrations of inflammatory markers are reported. After the intervention, the membrane cholesterol content decreased, whereas that of phospholipids increased in all of the dietary groups; the diminishing cholesterol:phospholipid ratio could be associated with an increase in the membrane fluidity. Moreover, reconstituted membranes from the nuts and virgin olive oil groups showed a higher propensity to form a nonlamellar inverted hexagonal phase structure that was related to an increase in phosphatidylethanolamine lipid class. These data suggest that the Mediterranean-style diet affects the lipid metabolism that is altered in hypertensive patients, influencing the structural membrane properties. The erythrocyte membrane modulation described provides insight in the structural bases underlying the beneficial effect of a Mediterranean-style diet in hypertensive subjects.

  6. Effect of treatment on erythrocyte phosphoribosyl pyrophosphate synthetase and glutathione reductase activity in patients with primary gout.

    PubMed Central

    Braven, J; Hardwell, T R; Hickling, P; Whittaker, M

    1986-01-01

    The activities of erythrocyte phosphoribosyl pyrophosphate (PRPP) synthetase and glutathione reductase (GTR) were studied in 26 patients with primary gout who were receiving no treatment or treatment with either allopurinol or azapropazone, and compared with the activity in a group of healthy controls. The activity of PRPP synthetase was significantly higher in the gout group and was not influenced by either drug. No significant difference in the activity of GTR was observed. The failure of either drug to suppress the increased activity of PRPP synthetase associated with gout is discussed. PMID:3024593

  7. Evidence that verotoxins (Shiga-like toxins) from Escherichia coli bind to P blood group antigens of human erythrocytes in vitro.

    PubMed Central

    Bitzan, M; Richardson, S; Huang, C; Boyd, B; Petric, M; Karmali, M A

    1994-01-01

    The interaction of verotoxins (VTs) with human erythrocytes (RBCs) in vitro was investigated, with particular reference to the role of P blood group glycolipids that are structurally related to the known VT receptors. RBC binding of purified VT1, VT2, VT2c, and VT2e was detected by direct and indirect immunofluorescence. Glycolipids were extracted from defined RBCs, separated by thin-layer chromatography, and assessed for VT binding in an overlay assay by adding toxin and specific antibodies. All VTs bound to P1 phenotype (Pk, P, and P1 antigens) and P2 phenotype (Pk and P antigens) RBCs but not to p phenotype (lacking the Pk, P, and P1 antigens) RBCs. Binding of VT1 and VT2 was approximately 10-fold greater to P1 and the rare Pk2 (Pk antigen but no P1 or P antigen) phenotype cells than to P2 phenotype RBCs, whereas VT2e bound equally well to P1 and P2 phenotype cells. The VT1 and VT2 immunofluorescence results correlated with the detection of P1 and/or increased amounts of Pk (globotriaosylceramide) antigen; VT2e immunofluorescence correlated with the detection of P (globotetraosylceramide) antigen. The Pk band pattern and VT binding observed in the thin-layer chromatogram of human P1 and P phenotype RBC extracts varied from that of human kidney and Pk1 phenotype (Pk and P1 antigens) RBCs. We conclude that each VT binds to human RBCs in vitro by utilizing specific P blood group glycolipids as receptors. On P1 and P phenotype RBCs, the accessibility of the Pk antigen for VTs appeared to be restricted. The occurrence of VT-RBC binding in natural VT-producing Escherichia coli disease and its relevance for the pathophysiology of hemolytic uremic syndrome remain to be established. Images PMID:8039905

  8. Erythrocytes in nanomedicine: an optimal blend of natural and synthetic materials.

    PubMed

    Zhang, Haijun

    2016-07-21

    A hybrid approach strategy using synthetic nanoparticles and erythrocytes offers an optimal blend of natural and synthetic materials. The combined advantages of erythrocytes and nanoparticles could serve as an immune-evasive multifunctional platform. This review summarized the research on state-of-the-art and significant advances in erythrocytes for nanomedicine, and presented are their fabrication process, their unique properties and applications. According to its structure, this review mainly focuses on three kinds of erythrocyte-based nanomedicine: whole erythrocytes as carriers, cell membrane coated nanoparticles, and nanoerythrosomes. In addition, some future prospects are also prudentially addressed. We expect rapid success in the advancement of erythrocyte-based nanomedicines, from the bench to the bedside.

  9. Anti-Self Phosphatidylserine Antibodies Recognize Uninfected Erythrocytes Promoting Malarial Anemia.

    PubMed

    Fernandez-Arias, Cristina; Rivera-Correa, Juan; Gallego-Delgado, Julio; Rudlaff, Rachel; Fernandez, Clemente; Roussel, Camille; Götz, Anton; Gonzalez, Sandra; Mohanty, Akshaya; Mohanty, Sanjib; Wassmer, Samuel; Buffet, Pierre; Ndour, Papa Alioune; Rodriguez, Ana

    2016-02-10

    Plasmodium species, the parasitic agents of malaria, invade erythrocytes to reproduce, resulting in erythrocyte loss. However, a greater loss is caused by the elimination of uninfected erythrocytes, sometimes long after infection has been cleared. Using a mouse model, we found that Plasmodium infection induces the generation of anti-self antibodies that bind to the surface of uninfected erythrocytes from infected, but not uninfected, mice. These antibodies recognize phosphatidylserine, which is exposed on the surface of a fraction of uninfected erythrocytes during malaria. We find that phosphatidylserine-exposing erythrocytes are reticulocytes expressing high levels of CD47, a "do-not-eat-me" signal, but the binding of anti-phosphatidylserine antibodies mediates their phagocytosis, contributing to anemia. In human patients with late postmalarial anemia, we found a strong inverse correlation between the levels of anti-phosphatidylserine antibodies and plasma hemoglobin, suggesting a similar role in humans. Inhibition of this pathway may be exploited for treating malarial anemia.

  10. Modifications of a cholinesterase method for determination of erythrocyte cholinesterase activity in wild mammals.

    PubMed

    Donovan, D A; Zinkl, J G

    1994-04-01

    A method to determine erythrocyte cholinesterase (ChE) activity was modified for use in wild mammals. Erythrocyte ChE of California voles (Microtus californicus) was primarily acetylcholinesterase (AChE), which was similar to the brain and unlike plasma which was primarily butyrylcholinesterase (BChE). Triplicate erythrocyte AChE analyses from individual animals of several species of wild rodents revealed a mean coefficient of variation of 8.7% (SD = 4.3%). Erythrocyte ChE activity of several wild mammals of California revealed that mule deer (Odocoileus hemionus) had the highest erythrocyte AChE activity (1,514.5 mU/ml) and dusky-footed woodrats (Neotoma fuscipes) had the lowest activity (524.3 mU/ml). No ChE activity was found in erythrocytes of several species of birds and fish. PMID:8028108

  11. Simultaneous in vivo phenotyping of CYP enzymes.

    PubMed

    Ghassabian, Sussan; Murray, Michael

    2013-01-01

    As major determinants of the duration of drug action the CYP enzymes strongly influence drug efficacy and toxicity. In vivo phenotyping for CYP activities using cocktails of well-tolerated CYP-specific substrates may be valuable in the development of personalized medicine protocols, particularly for drugs that have significant toxicity profiles. However, the use of the cocktail approach in the clinic is dependent on the rapid provision of patient-specific information to the clinician. Here we describe the application of liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the simultaneous phenotyping of five major drug-metabolizing CYPs in patients within a 5-min assay.

  12. Functional significance of glutamate-cysteine ligase modifier for erythrocyte survival in vitro and in vivo.

    PubMed

    Föller, M; Harris, I S; Elia, A; John, R; Lang, F; Kavanagh, T J; Mak, T W

    2013-10-01

    Erythrocytes endure constant exposure to oxidative stress. The major oxidative stress scavenger in erythrocytes is glutathione. The rate-limiting enzyme for glutathione synthesis is glutamate-cysteine ligase, which consists of a catalytic subunit (GCLC) and a modifier subunit (GCLM). Here, we examined erythrocyte survival in GCLM-deficient (gclm(-/-)) mice. Erythrocytes from gclm(-/-) mice showed greatly reduced intracellular glutathione. Prolonged incubation resulted in complete lysis of gclm(-/-) erythrocytes, which could be reversed by exogenous delivery of the antioxidant Trolox. To test the importance of GCLM in vivo, mice were treated with phenylhydrazine (PHZ; 0.07 mg/g b.w.) to induce oxidative stress. Gclm(-/-) mice showed dramatically increased hemolysis compared with gclm(+/+) controls. In addition, PHZ-treated gclm(-/-) mice displayed markedly larger accumulations of injured erythrocytes in the spleen than gclm(+/+) mice within 24 h of treatment. Iron staining indicated precipitations of the erythrocyte-derived pigment hemosiderin in kidney tubules of gclm(-/-) mice and none in gclm(+/+) controls. In fact, 24 h after treatment, kidney function began to diminish in gclm(-/-) mice as evident from increased serum creatinine and urea. Consequently, while all PHZ-treated gclm(+/+) mice survived, 90% of PHZ-treated gclm(-/-) mice died within 5 days of treatment. In vitro, upon incubation in the absence or presence of additional oxidative stress, gclm(-/-) erythrocytes exposed significantly more phosphatidylserine, a cell death marker, than gclm(+/+) erythrocytes, an effect at least partially due to increased cytosolic Ca(2+) concentration. Under resting conditions, gclm(-/-) mice exhibited reticulocytosis, indicating that the enhanced erythrocyte death was offset by accelerated erythrocyte generation. GCLM is thus indispensable for erythrocyte survival, in vitro and in vivo, during oxidative stress.

  13. Parathyroid hormone ablation alters erythrocyte parameters that are rescued by calcium-sensing receptor gene deletion.

    PubMed

    Romero, Jose R; Youte, Rodeler; Brown, Edward M; Pollak, Martin R; Goltzman, David; Karaplis, Andrew; Pong, Lie-Chin; Chien, Lawrence; Chattopadhyay, Naibedya; Rivera, Alicia

    2013-07-01

    The mechanisms by which parathyroid hormone (PTH) produces anemia are unclear. Parathyroid hormone secretion is regulated by the extracellular Ca2+ -sensing receptor. We investigated the effects of ablating PTH on hematological indices and erythrocytes volume regulation in wild-type, PTH-null, and Ca2+ -sensing receptor-null/PTH-null mice. The erythrocyte parameters were measured in whole mouse blood, and volume regulatory systems were determined by plasma membrane K+ fluxes, and osmotic fragility was measured by hemoglobin determination at varying osmolarities. We observed that the absence of PTH significantly increases mean erythrocyte volume and reticulocyte counts, while decreasing erythrocyte counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin concentration. These changes were accompanied by increases in erythrocyte cation content, a denser cell population, and increased K+ permeability, which were in part mediated by activation of the K+ /Cl- cotransporter and Gardos channel. In addition we observed that erythrocyte osmotic fragility in PTH-null compared with wild-type mice was enhanced. When Ca2+ -sensing receptor gene was deleted on the background of PTH-null mice, we observed that several of the alterations in erythrocyte parameters of PTH-null mice were largely rescued, particularly those related to erythrocyte volume, K+ fluxes and osmotic fragility, and became similar to those observed in wild-type mice. Our results demonstrate that Ca2+ -sensing receptor and parathyroid hormone are functionally coupled to maintain erythrocyte homeostasis. PMID:23528155

  14. Studies on the role of goat heart galectin-1 as an erythrocyte membrane perturbing agent.

    PubMed

    Ashraf, Ghulam Md; Perveen, Asma; Zaidi, Syed Kashif; Tabrez, Shams; Kamal, Mohammad A; Banu, Naheed

    2015-01-01

    Galectins are β-galactoside binding lectins with a potential hemolytic role on erythrocyte membrane integrity and permeability. In the present study, goat heart galectin-1 (GHG-1) was purified and investigated for its hemolytic actions on erythrocyte membrane. When exposed to various saccharides, lactose and sucrose provided maximum protection against hemolysis, while glucose and galactose provided lesser protection against hemolysis. GHG-1 agglutinated erythrocytes were found to be significantly hemolyzed in comparison with unagglutinated erythrocytes. A concentration dependent rise in the hemolysis of trypsinized rabbit erythrocytes was observed in the presence of GHG-1. Similarly, a temperature dependent gradual increase in percent hemolysis was observed in GHG-1 agglutinated erythrocytes as compared to negligible hemolysis in unagglutinated cells. The hemolysis of GHG-1 treated erythrocytes showed a sharp rise with the increasing pH up to 7.5 which became constant till pH 9.5. The extent of erythrocyte hemolysis increased with the increase in the incubation period, with maximum hemolysis after 5 h of incubation. The results of this study establish the ability of galectins as a potential hemolytic agent of erythrocyte membrane, which in turn opens an interesting avenue in the field of proteomics and glycobiology.

  15. Changes in the nuclear matrix of chicken erythrocytes that accompany maturation.

    PubMed Central

    Chen, H Y; Sun, J M; Hendzel, M J; Rattner, J B; Davie, J R

    1996-01-01

    The protein composition and structure of nuclear matrices isolated from adult chicken immature and mature erythrocytes were analysed. Visualization of nuclear matrices by electron microscopy showed that immature-erythrocyte nuclear matrices had internal structures, while most mature-erythrocyte nuclear matrices did not. Both mature- and immature-erythrocyte nuclear matrices were surrounded by a fibrous network of intermediate filaments. Two-dimensional gel electrophoretic analysis of proteins obtained from fractionated nuclear matrices led to the assignment of the proteins as components of the nuclear porelamina, internal matrix, or cytoskeleton. Common and different proteins belonging to one of the three groups were identified in nuclear matrices of immature and mature erythrocytes. Investigation of the partitioning of histone deacetylase activity, an enzyme associated with the internal matrix, among the erythroid nuclear matrix fractions provided evidence that mature- and immature-erythrocyte nuclear matrices have internal structures. However, the activity of histone deacetylase and level of internal matrix proteins from mature-erythrocyte nuclear matrices were less than those from immature-erythrocyte matrices. The low levels of nuclear RNA and internal matrix proteins may account for lack of visual evidence for an internal matrix in mature erythrocytes. PMID:8947496

  16. Effect of dietary zinc deficiency on the endogenous phosphorylation and dephosphorylation of rat erythrocyte membrane

    SciTech Connect

    Paterson, P.G.; Allen, O.B.; Bettger, W.J.

    1987-12-01

    The effect of dietary zinc deficiency on patterns of phosphorylation and dephosphorylation of rat erythrocyte membrane proteins and erythrocyte filterability was examined. Weanling male Wistar rats were fed an egg white-based diet containing less than 1.1 mg zinc/kg diet ad libitum for 3 wk. Control rats were either pair-fed or ad libitum-fed the basal diet supplemented with 100 mg zinc/kg diet. Net phosphorylation and dephosphorylation of erythrocyte membrane proteins were carried out by an in vitro assay utilizing (gamma-/sup 32/P)ATP. The membrane proteins were subsequently separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the /sup 32/P content of gel slices was counted by Cerenkov counting. Erythrocyte filterability was measured as the filtration time of suspensions of erythrocytes, both untreated and preincubated with diamide, under constant pressure. Erythrocyte ghosts from zinc-deficient rats demonstrated greater dephosphorylation of protein bands R1 plus R2 and R7 than pair-fed rats and greater net phosphorylation of band R2.2 than pair-fed or ad libitum-fed control rats (P less than 0.05). Erythrocytes from ad libitum-fed control rats showed significantly longer filtration times than those from zinc-deficient or pair-fed control rats. In conclusion, dietary zinc deficiency alters in vitro patterns of erythrocyte membrane protein phosphorylation and dephosphorylation, whereas the depression in food intake associated with the zinc deficiency increases erythrocyte filterability. 71 references.

  17. Insect erythrocyte agglutinins. In vitro opsonization experiments with Clitumnus extradentatus and Periplaneta americana haemocytes.

    PubMed Central

    Rowley, A F; Ratcliffe, N A

    1980-01-01

    The effect of naturally occurring haemagglutinins on the in vitro phagocytosis of sheep erythrocytes by the blood cells (haemocytes) of Clitumnus extradentatus and Periplaneta americana was studied. The results showed that the haemagglutinins in both species failed to act as opsonins. Indeed, in some instances, incubation of erythrocytes in haemolymph resulted in less avid ingestion as compared with the saline-incubated controls. This reduced phagocytosis was probably caused by the clumping of erythrocytes on the haemocyte monolayers, leaving fewer single red cells available for uptake. The possible roles of these erythrocyte agglutinins in the host defence systems of insects are discussed. Images Figures 1-3 Figures 6-7 PMID:7000682

  18. A Lectin-Like Receptor is Involved in Invasion of Erythrocytes by Plasmodium falciparum

    NASA Astrophysics Data System (ADS)

    Jungery, M.; Pasvol, G.; Newbold, C. I.; Weatherall, D. J.

    1983-02-01

    Glycophorin both in solution and inserted into liposomes blocks invasion of erythrocytes by the malaria parasite Plasmodium falciparum. Furthermore, one sugar, N-acetyl-D-glucosamine (GlcNAc), completely blocks invasion of the erythrocyte by this parasite. GlcNAc coupled to bovine serum albumin to prevent the sugar entering infected erythrocytes was at least 100,000 times more effective than GlcNAc alone. Bovine serum albumin coupled to lactose or bovine serum albumin alone had no effect on invasion. These results suggest that the binding of P. falciparum to erythrocytes is lectin-like and is determined by carbohydrates on glycophorin.

  19. Microfluidic isolation of leukocytes from whole blood for phenotype and gene expression analysis.

    PubMed

    Sethu, Palaniappan; Moldawer, Lyle L; Mindrinos, Michael N; Scumpia, Philip O; Tannahill, Cynthia L; Wilhelmy, Julie; Efron, Philip A; Brownstein, Bernard H; Tompkins, Ronald G; Toner, Mehmet

    2006-08-01

    Technologies that enable the isolation of cell subtypes from small samples of complex populations will greatly facilitate the implementation of proteomics and genomics to human diseases. Transcriptome analysis of blood requires the depletion of contaminating erythrocytes. We report an automated microfluidic device to rapidly deplete erythrocytes from whole blood via deionized water lysis and to collect enriched leukocytes for phenotype and genomic analyses. Starting with blood from healthy subjects, we demonstrate the utility of this microfluidic cassette and lysis protocol to prepare unstimulated leukocytes, and leukocytes stimulated ex vivo with Staphylococcal enterotoxin B, which mimics some of the cellular effects seen in patients with severe bacterial infections. Microarrays are used to assess the global gene expression response to enterotoxin B. The results demonstrate that this system can isolate unactivated leukocytes from small blood samples without any significant loss, which permits more information to be obtained from subsequent analysis, and will be readily applicable to clinical settings.

  20. Down Syndrome: Cognitive Phenotype

    ERIC Educational Resources Information Center

    Silverman, Wayne

    2007-01-01

    Down syndrome is the most prevalent cause of intellectual impairment associated with a genetic anomaly, in this case, trisomy of chromosome 21. It affects both physical and cognitive development and produces a characteristic phenotype, although affected individuals vary considerably with respect to severity of specific impairments. Studies…

  1. Ultrasonic Backscattering from Suspended Erythrocytes: Dependence on Frequency and Size.

    NASA Astrophysics Data System (ADS)

    Kuo, Ihyuan

    The ultrasonic scattering properties of blood have been intensively investigated since the echo signal from red blood cells carries abundant diagnostic information for the study of blood flow and blood properties in the vessels. Recently, ultrasound of frequency higher than 20 MHz has been implemented in intravascular imaging to obtain better images of the vessel wall. In this research measurements were extended to 30 MHz to better understand the effect of blood on the operation of these intravascular devices. The experimentally measured backscatter of saline suspended porcine erythrocytes for frequency up to 30 MHz agrees very well with the theoretical analysis which indicate that Rayleigh scattering is still valid below this frequency. The analysis utilize the T-matrix method to calculate the backscattering cross section of an erythrocyte modeled as a fluid sphere, disk, and biconcave disk. Measurements on the backscattering coefficients of porcine, bovine, and lamb erythrocytes reveal that the backscatter has a square dependence on cell volume. The cell size dependent backscatter is also analyzed via a continuum approach. It is found that the echo intensity of high frequency ultrasound suffers greatly from the attenuation. The dilemma may be solved by using a spherically focused transducer. An analysis of the focused beam reflected from a perfect planar reflector leads to the modification of the standard substitution method for the backscatter measurement since the "image source" theory is found to be inappropriate for the focused beam. Reflection of the focused beam near the focal point is described based on Huygens' principle. Experimental and theoretical results indicate that the backscatter is dependent upon the position of the scatterer and the geometry of the transducer if a focused beam is used. Since ultrasound velocity information is needed for scattering measurements, an innovative method for measuring the acoustic speed and the attenuation coefficient

  2. Human erythrocytes analyzed by generalized 2D Raman correlation spectroscopy

    NASA Astrophysics Data System (ADS)

    Wesełucha-Birczyńska, Aleksandra; Kozicki, Mateusz; Czepiel, Jacek; Łabanowska, Maria; Nowak, Piotr; Kowalczyk, Grzegorz; Kurdziel, Magdalena; Birczyńska, Malwina; Biesiada, Grażyna; Mach, Tomasz; Garlicki, Aleksander

    2014-07-01

    The most numerous elements of the blood cells, erythrocytes, consist mainly of two components: homogeneous interior filled with hemoglobin and closure which is the cell membrane. To gain insight into their specific properties we studied the process of disintegration, considering these two constituents, and comparing the natural aging process of human healthy blood cells. MicroRaman spectra of hemoglobin within the single RBC were recorded using 514.5, and 785 nm laser lines. The generalized 2D correlation method was applied to analyze the collected spectra. The time passed from blood donation was regarded as an external perturbation. The time was no more than 40 days according to the current storage limit of blood banks, although, the average RBC life span is 120 days. An analysis of the prominent synchronous and asynchronous cross peaks allow us to get insight into the mechanism of hemoglobin decomposition. Appearing asynchronous cross-peaks point towards globin and heme separation from each other, while synchronous shows already broken globin into individual amino acids. Raman scattering analysis of hemoglobin “wrapping”, i.e. healthy erythrocyte ghosts, allows for the following peculiarity of their behavior. The increasing power of the excitation laser induced alterations in the assemblage of membrane lipids. 2D correlation maps, obtained with increasing laser power recognized as an external perturbation, allows for the consideration of alterations in the erythrocyte membrane structure and composition, which occurs first in the proteins. Cross-peaks were observed indicating an asynchronous correlation between the senescent-cell antigen (SCA) and heme or proteins vibrations. The EPR spectra of the whole blood was analyzed regarding time as an external stimulus. The 2D correlation spectra points towards participation of the selected metal ion centers in the disintegration process.

  3. Erythrocyte osmotic fragility and oxidative stress in experimental hypothyroidism.

    PubMed

    Dariyerli, Nuran; Toplan, Selmin; Akyolcu, Mehmet Can; Hatemi, Husrev; Yigit, Gunnur

    2004-10-01

    The present study was planned to explain the relation between erythrocyte osmotic fragility and oxidative stress and antioxidant statue in primary hypothyroid-induced experimental rats. Twenty-four Spraque Dawley type female rats were divided into two, as control (n = 12) and experimental (n = 12), groups weighing between 160 and 200 g. The experimental group animals have received tap water methimazole added standard fodder to block the iodine pumps for 30 d (75 mg/100 g). Control group animals were fed tap water and only standard fodder for the same period. At the end of 30 d blood samples were drawn from the abdominal aorta of the rats under ether anesthesia. T3, T4, and TSH levels were measured and the animals that had relatively lower T3, T4, and higher TSH levels were accepted as hypothyroid group. Hormone levels of the control group were at euthyroid conditions. Osmotic fragility, as a lipid peroxidation indicator malondialdehyde (MDA), antioxidant defense system indicators superoxide dismutase (SOD) and glutathione (GSH) levels were measured in the blood samples. Osmotic fragility test results: There was no statistically significant difference found between maximum osmotic hemolysis limit values of both group. Minimum osmotic hemolysis limit value of hypothyroid group was found to be higher than that of control group values (p < 0.02). The standard hemolysis and hemolytic increment curve of the hypothyroid group drawn according to osmotic fragility test results was found to be shifted to the right when compared to control group's curve. This situation and hemolytic increment value, which shows maximum hemolysis ratio, is the proof of increased osmotic fragility of the erythrocytes in hypothyroidism. There is no statistically significant difference found between hypothyroid and control groups in the lipid peroxidation indicator MDA and antioxidant indicators SOD and GSH levels. As a result of our study it may be concluded that hypothyroidism may lead to an

  4. Human erythrocytes have binding sites for beta-endorphin.

    PubMed Central

    Simpkins, C. O.; Chenet, B. P.; Kang, Y. H.; Mazorow, D. L.; Millar, D. B.; Hollis, V. W.

    1989-01-01

    Monoiodinated human beta-endorphin was found to bind specifically to human erythrocytes. Unlabeled beta-endorphin and beta-endorphin inhibited binding, but (-)naloxone, [D-Ala2, D-Leu5]-enkephalin, and leu- and met-enkephalin did not. Immunoelectron microscopy, using rabbit anti-beta-endorphin antibody, an antirabbit IgG secondary antibody, and complexed horseradish peroxidase, revealed that at low concentrations beta-endorphin binds to the cell surface. Electron spin resonance spectroscopy showed no effect of beta-endorphin on membrane fluidity. This receptor does not appear to conform to the characteristics of an opiate receptor. Images Figures 2 and 3 PMID:2560064

  5. Solubilization of native actin monomers from human erythrocyte membranes.

    PubMed

    Tilley, L; Dwyer, M; Ralston, G B

    1986-01-01

    Up to 50% of the actin in erythrocyte membranes can be solubilized at low ionic strength in a form capable of inhibiting DNAse I, in the presence of 0.4 mM ATP and 0.05 mM calcium. In the absence of calcium and ATP, actin is released but is apparently rapidly denatured. Solubilization of G-actin increases with temperature up to 37 degrees C. At higher temperatures, actin is released rapidly but quickly loses its ability to inhibit DNAse I. PMID:3789986

  6. Malaria parasite pre-erythrocytic stage infection: Gliding and Hiding

    PubMed Central

    Vaughan, Ashley M.; Aly, Ahmed S. I.; Kappe, Stefan H. I.

    2008-01-01

    Summary Malaria is caused by red blood cell-infectious forms of Plasmodium parasites resulting in illness and possible death of infected hosts. The mosquito-borne sporozoite stage of the parasite and the initial infection in the liver, however cause little pathology and no symptoms. Nevertheless, these pre-erythrocytic parasite stages are attracting passionate research efforts not least because they are the most promising targets for malaria vaccine development. Here, we review how the infectious sporozoite makes its way to the liver, subsequently develops in hepatocytes and the factors, both parasite and host, involved in the interactions that occur during this ‘silent’ phase of infection. PMID:18779047

  7. [Rate of erythrocyte sedimentation in buffaloes in related to age].

    PubMed

    d'Angelo, A; Zicarelli, L; Damiano, B; Avallone, L; Crasto, A

    1984-03-30

    The behavior of the ERS was studied in water buffalo of both sexes from one week to nine years of age. A progressive and considerable increase in the values of the ERS, with a respective increase in the animal's age, was noted. Concerning the factors conditioning such peculiarities, the authors attribute importance to the following items: the number of erythrocytes, the plasmatic viscosity, and the total proteinemia (especially in the region of the gamma-globulins that, among those taken in the study, exhibited the greatest variations).

  8. Behavioural phenotypes predict disease susceptibility and infectiousness.

    PubMed

    Araujo, Alessandra; Kirschman, Lucas; Warne, Robin W

    2016-08-01

    Behavioural phenotypes may provide a means for identifying individuals that disproportionally contribute to disease spread and epizootic outbreaks. For example, bolder phenotypes may experience greater exposure and susceptibility to pathogenic infection because of distinct interactions with conspecifics and their environment. We tested the value of behavioural phenotypes in larval amphibians for predicting ranavirus transmission in experimental trials. We found that behavioural phenotypes characterized by latency-to-food and swimming profiles were predictive of disease susceptibility and infectiousness defined as the capacity of an infected host to transmit an infection by contacts. While viral shedding rates were positively associated with transmission, we also found an inverse relationship between contacts and infections. Together these results suggest intrinsic traits that influence behaviour and the quantity of pathogens shed during conspecific interactions may be an important contributor to ranavirus transmission. These results suggest that behavioural phenotypes provide a means to identify individuals more likely to spread disease and thus give insights into disease outbreaks that threaten wildlife and humans. PMID:27555652

  9. Single cell dynamic phenotyping

    PubMed Central

    Patsch, Katherin; Chiu, Chi-Li; Engeln, Mark; Agus, David B.; Mallick, Parag; Mumenthaler, Shannon M.; Ruderman, Daniel

    2016-01-01

    Live cell imaging has improved our ability to measure phenotypic heterogeneity. However, bottlenecks in imaging and image processing often make it difficult to differentiate interesting biological behavior from technical artifact. Thus there is a need for new methods that improve data quality without sacrificing throughput. Here we present a 3-step workflow to improve dynamic phenotype measurements of heterogeneous cell populations. We provide guidelines for image acquisition, phenotype tracking, and data filtering to remove erroneous cell tracks using the novel Tracking Aberration Measure (TrAM). Our workflow is broadly applicable across imaging platforms and analysis software. By applying this workflow to cancer cell assays, we reduced aberrant cell track prevalence from 17% to 2%. The cost of this improvement was removing 15% of the well-tracked cells. This enabled detection of significant motility differences between cell lines. Similarly, we avoided detecting a false change in translocation kinetics by eliminating the true cause: varied proportions of unresponsive cells. Finally, by systematically seeking heterogeneous behaviors, we detected subpopulations that otherwise could have been missed, including early apoptotic events and pre-mitotic cells. We provide optimized protocols for specific applications and step-by-step guidelines for adapting them to a variety of biological systems. PMID:27708391

  10. Pressure-induced hemolysis of in vivo aged human erythrocytes is enhanced by inhibition of water transport via aquaporin-1

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Takeo; Miyauchi, Shin; Isahara, Yasuyuki

    2013-06-01

    Human erythrocytes are fractionated into young, intermediate, and old cells according to their densities. Pressure-induced hemolysis reflects sensitively membrane perturbations. Therefore, the hemolysis of erythrocytes at 200 MPa was examined using fractionated cells. Pressure-induced hemolysis of old (or in vivo aged) erythrocytes was enhanced, compared with those of young and intermediate cells which showed the same hemolytic values. Flow cytometric analysis showed less fragmentation of old erythrocytes under pressure. Moreover, the water transport through the membrane was suppressed in old erythrocytes than intermediate ones. The low permeability of water in old erythrocytes was confirmed by osmotic hemolysis using a hypotonic buffer. These results suggest that water transport via aquaporin-1 (AQP1) is inhibited in old erythrocytes. As the number of AQP1 molecules remained constant in old erythrocytes, the function of AQP1 may be reduced.

  11. Plasmodium induces swelling-activated ClC-2 anion channels in the host erythrocyte.

    PubMed

    Huber, Stephan M; Duranton, Christophe; Henke, Guido; Van De Sand, Claudia; Heussler, Volker; Shumilina, Ekaterina; Sandu, Ciprian D; Tanneur, Valerie; Brand, Verena; Kasinathan, Ravi S; Lang, Karl S; Kremsner, Peter G; Hübner, Christian A; Rust, Marco B; Dedek, Karin; Jentsch, Thomas J; Lang, Florian

    2004-10-01

    Intraerythrocytic growth of the human malaria parasite Plasmodium falciparum depends on delivery of nutrients. Moreover, infection challenges cell volume constancy of the host erythrocyte requiring enhanced activity of cell volume regulatory mechanisms. Patch clamp recording demonstrated inwardly and outwardly rectifying anion channels in infected but not in control erythrocytes. The molecular identity of those channels remained elusive. We show here for one channel type that voltage dependence, cell volume sensitivity, and activation by oxidation are identical to ClC-2. Moreover, Western blots and FACS analysis showed protein and functional ClC-2 expression in human erythrocytes and erythrocytes from wild type (Clcn2(+/+)) but not from Clcn2(-/-) mice. Finally, patch clamp recording revealed activation of volume-sensitive inwardly rectifying channels in Plasmodium berghei-infected Clcn2(+/+) but not Clcn2(-/-) erythrocytes. Erythrocytes from infected mice of both genotypes differed in cell volume and inhibition of ClC-2 by ZnCl(2) (1 mm) induced an increase of cell volume only in parasitized Clcn2(+/+) erythrocytes. Lack of ClC-2 did not inhibit P. berghei development in vivo nor substantially affect the mortality of infected mice. In conclusion, activation of host ClC-2 channels participates in the altered permeability of Plasmodium-infected erythrocytes but is not required for intraerythrocytic parasite survival. PMID:15272009

  12. Slow Freezing Coupled Static Magnetic Field Exposure Enhances Cryopreservative Efficiency—A Study on Human Erythrocytes

    PubMed Central

    Lin, Chun-Yen; Wei, Po-Li; Chang, Wei-Jen; Huang, Yung-Kai; Feng, Sheng-Wei; Lin, Che-Tong; Lee, Sheng-Yang; Huang, Haw-Ming

    2013-01-01

    The aim of this study was to assess the cryoprotective effect of static magnetic fields (SMFs) on human erythrocytes during the slow cooling procedure. Human erythrocytes suspended in 20% glycerol were slowly frozen with a 0.4-T or 0.8-T SMF and then moved to a −80°C freezer for 24 hr. The changes in survival rate, morphology, and metabolites of the thawed erythrocytes were examined. To understand possible cryoprotective mechanisms of SMF, membrane fluidity and dehydration stability of SMF-exposed erythrocytes were tested. For each test, sham-exposed erythrocytes were used as controls. Our results showed that freezing coupled with 0.4-T or 0.8-T SMFs significantly increased the relative survival ratios of the frozen-thawed erythrocytes by 10% and 20% (p<0.001), respectively. The SMFs had no effect on erythrocyte morphology and metabolite levels. However, membrane fluidity of the samples exposed to 0.8-T SMF decreased significantly (p<0.05) in the hydrophobic regions. For the dehydration stability experiments, the samples exposed to 0.8-T SMF exhibited significantly lower (p<0.05) hemolysis. These results demonstrate that a 0.8-T SMF decreases membrane fluidity and enhances erythrocyte membrane stability to resist dehydration damage caused by slow cooling procedures. PMID:23520546

  13. The binding of calcium ions by erythrocytes and 'ghost' -cell membranes.

    PubMed

    Long, C; Mouat, B

    1971-08-01

    1. Washed human erythrocytes, suspended in iso-osmotic sucrose containing 2.5mm-calcium chloride, bind about 400mug-atoms of calcium/litre of packed cells. Sucrose may be replaced by other sugars. 2. Partial replacement of sucrose by iso-osmotic potassium chloride diminishes the uptake of calcium, 50% inhibition occurring at about 50mm-potassium chloride. 3. Other univalent cations behave like potassium, whereas bivalent cations are much more inhibitory. The tervalent cations, yttrium and lanthanum, however, are the most effective inhibitors of calcium uptake. 4. An approximate correlation exists between the calcium uptake and the sialic acid content of erythrocytes of various species and of human erythrocytes that have been partially depleted of sialic acid by treatment with neuraminidase. However, even after complete removal of sialic acid, human erythrocytes still bind about 140mug-atoms of calcium/litre of packed cells. 5. A Scatchard (1949) plot of calcium uptake at various Ca(2+) concentrations in the suspending media shows the presence of three different binding sites on the external surface of the human erythrocyte membrane. 6. Erythrocyte ;ghost' cells, the membranes of which appear to be permeable to Ca(2+) ions, can bind about 1000mug-atoms of calcium per ;ghost'-cell equivalent of 1 litre of packed erythrocytes. This indicates that there are also binding sites for calcium on the internal surface of the erythrocyte membrane. PMID:5124387

  14. Cinnarizine and flunarizine improve the tumour radiosensitisation induced by erythrocyte transfusion in anaemic mice.

    PubMed Central

    Wood, P. J.; Hirst, D. G.

    1989-01-01

    The ability of the calcium antagonists, cinnarizine and flunarizine, to enhance the radiosensitisation produced by the administration of an erythrocyte transfusion to anaemic, RIF-1 or SCCVII/St tumour bearing mice was determined. Erythrocyte transfusion alone increased radiation cell killing 10-fold in the RIF-1 tumour when given 0-4 h before X-rays. In contrast, the SCCVII/St showed only a 4-fold increase in sensitivity, apparent when erythrocytes were given 2-6 h before irradiation. The administration of 50 mg kg-1 cinnarizine or flunarizine to anaemic mice followed by erythrocyte transfusion 0 h before X-rays produced the same level of cell survival for both tumours, a 20-fold increase in cell killing for cinnarizine, and a 30-40-fold effect for flunarizine, even though at this time interval, the erythrocyte transfusion alone did not sensitise the SCCVII/St tumour to X-rays. Further investigations indicated, however, that the erythrocyte transfusion was necessary to achieve the sensitisation with the calcium antagonists, since giving flunarizine to anaemic mice alone only achieved a 4-fold increase in radiation cell killing. In addition, flunarizine given with erythrocyte transfusion 4 h before X-rays, in SCCVII/St, the optimal time for radiosensitisation in this tumour, did not further increase the level of cell killing achieved by flunarizine plus erythrocyte transfusion 0 h before X-rays. PMID:2803913

  15. Human autologous and allogeneic rosettes with erythrocytes of the Bombay type.

    PubMed

    Lang, J M; Bigel, P; Mayer, S

    1977-06-01

    Human red blood cells of the Bombay type which lack ABH group substances can bind to allogeneic lymphocytes just as well as erythrocytes of any other type. A much lower percentage of auto-rosettes between erythrocytes and lymphocytes from the Bombay donor was observed, a result which may be due at least partially to some T lymphocyte defect in the Bombay donor.

  16. PMCA activity and membrane tubulin affect deformability of erythrocytes from normal and hypertensive human subjects.

    PubMed

    Monesterolo, Noelia E; Nigra, Ayelen D; Campetelli, Alexis N; Santander, Verónica S; Rivelli, Juan F; Arce, Carlos A; Casale, Cesar H

    2015-11-01

    Our previous studies demonstrated formation of a complex between acetylated tubulin and brain plasma membrane Ca(2+)-ATPase (PMCA), and the effect of the lipid environment on structure of this complex and on PMCA activity. Deformability of erythrocytes from hypertensive human subjects was reduced by an increase in membrane tubulin content. In the present study, we examined the regulation of PMCA activity by tubulin in normotensive and hypertensive erythrocytes, and the effect of exogenously added diacylglycerol (DAG) and phosphatidic acid (PA) on erythrocyte deformability. Some of the key findings were that: (i) PMCA was associated with tubulin in normotensive and hypertensive erythrocytes, (ii) PMCA enzyme activity was directly correlated with erythrocyte deformability, and (iii) when tubulin was present in the erythrocyte membrane, treatment with DAG or PA led to increased deformability and associated PMCA activity. Taken together, our findings indicate that PMCA activity is involved in deformability of both normotensive and hypertensive erythrocytes. This rheological property of erythrocytes is affected by acetylated tubulin and its lipid environment because both regulate PMCA activity.

  17. Lysis of erythrocytes from stored human blood by phospholipase C (Bacillus cereus).

    PubMed Central

    Little, C; Rumsby, M G

    1980-01-01

    The ability of phospholipase C (Bacillus cereus) to lyse erythrocytes from human blood that had been stored under Transfusion Service conditions for up to 16 weeks has been examined. When incubated at 20 degrees C with enzyme (0.03 mg/ml, 55 units/ml) for up to 1 h fresh erythrocytes were not lysed. After about 4 weeks of storage a population of very readily lysed erythrocytes appeared. The morphological changes in erythrocytes from blood stored up to 16 weeks were examined by scanning electron microscopy. The proportion of very readily lysed erythrocytes correlated well with the proportion of spheroechinocytes I. This morphological form was shown to be preferentially removed by phospholipase C and before lysis a transient appearance of smooth spheres occurred. The decrease in blood ATP concentrations on storage was measured and found to correlate with the disappearance of discoid erythrocyte forms, but not directly with the increased susceptibility of the erythrocytes to lysis by the enzyme. However, erythrocytes of up to at least 15 weeks of age could be made less susceptible to lysis by pre-incubation in a medium designed to cause intracellular regeneration of ATP. During the lysis of spheroechinocytes I by electrophoretically pure recrystallized phospholipase C a rapid degradation of phosphatidylcholine, phosphatidylethanolamine and phosphatidylserine + phosphatidylinositol) occurred together with a slower degradation of sphingomyelin. Images PLATE 2 PLATE 1 PMID:6773524

  18. Studies on erythrocyte membrane. V. Haemolytic effect of methylsalicylate and its possible mechanism.

    PubMed

    Murugesh, N; Kumar, V R; Vembar, S; Damodaran, C

    1981-11-01

    The haemolytic effect of methylsalicylate (MS) on human and sheep erythrocytes is reported for the first time to our knowledge. Human erythrocytes are more sensitive to this effect. Haemolysis is proportional to the concentration of methylsalicylate and the duration of incubation. Lowering of surface tension and the ensuing membrane damage appear to be the mechanism by which the haemolytic effect is produced.

  19. Studies on erythrocyte membrane. VII. In vitro haemolytic effect of Sesbania grandiflora leaves.

    PubMed

    Kumar, V R; Murugesh, N; Vembar, S; Damodaran, C

    1982-02-01

    Aqueous extract of the leaves of Sesbania grandiflora produced haemolysis of human and sheep erythrocytes even at very low concentrations. Haemolysis was greater when the pH was acidic. The liberation of phospholipids and sterols into the supernatant as a result of haemolysis indicated possible damage to the erythrocyte membrane.

  20. Dynamic and electrokinetic behavior of erythrocyte membrane in diabetes mellitus and diabetic cardiovascular disease.

    PubMed

    Adak, Sangeeta; Chowdhury, Subhankar; Bhattacharyya, Maitree

    2008-02-01

    The dynamic and electrokinetic properties of erythrocyte membrane are explored as significant indices involved in the association of diabetes and diabetic cardiovascular disease. Lipid peroxidation studies reveal malondialdehyde concentration to reach a maximum in diabetic cardiovascular patients. Lower fluidity of erythrocyte membrane implies declined ability of erythrocyte to deform in pathogenic state, which is supported by decreased osmotic resistance. Membrane protein profile modification detected by Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) indicates a significant reduction in the quantity of ankyrin protein band 2.1 in diabetic subjects. In addition the reduction in an immunoreactive band against polyclonal anti-ankyrin antibody during Western blot analysis confirms the modification of ankyrin protein in diseased erythrocyte (reported for the first time). The electrokinetic behavior of erythrocyte membrane is monitored by laser Doppler velocimetry mode of the Nano-ZS. Changes in zeta potential values of the red blood cell membrane are consistent with decreased membrane fluidity in diseased erythrocytes (reported for the first time). Membrane potential values of control, diabetic and diabetic cardiovascular erythrocytes are -37.24+/-1.5 mV, -28.44+/-1.34 mV, and -22.21+/-1.21 mV respectively indicating a gradual lowering of zeta potential when erythrocyte membrane undergoes progressive changes - from simple agglomeration to fluid gel formation - and finally to a rigid gel.

  1. Triggers, Inhibitors, Mechanisms, and Significance of Eryptosis: The Suicidal Erythrocyte Death

    PubMed Central

    Lang, Elisabeth

    2015-01-01

    Suicidal erythrocyte death or eryptosis is characterized by erythrocyte shrinkage, cell membrane blebbing, and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry, ceramide formation, stimulation of caspases, calpain activation, energy depletion, oxidative stress, and dysregulation of several kinases. Eryptosis is triggered by a wide variety of xenobiotics. It is inhibited by several xenobiotics and endogenous molecules including NO and erythropoietin. The susceptibility of erythrocytes to eryptosis increases with erythrocyte age. Phosphatidylserine exposing erythrocytes adhere to the vascular wall by binding to endothelial CXC-Motiv-Chemokin-16/Scavenger-receptor for phosphatidylserine and oxidized low density lipoprotein (CXCL16). Phosphatidylserine exposing erythrocytes are further engulfed by phagocytosing cells and are thus rapidly cleared from circulating blood. Eryptosis eliminates infected or defective erythrocytes thus counteracting parasitemia in malaria and preventing detrimental hemolysis of defective cells. Excessive eryptosis, however, may lead to anemia and may interfere with microcirculation. Enhanced eryptosis contributes to the pathophysiology of several clinical disorders including metabolic syndrome and diabetes, malignancy, cardiac and renal insufficiency, hemolytic uremic syndrome, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Facilitating or inhibiting eryptosis may be a therapeutic option in those disorders. PMID:25821808

  2. Severe pancytopenia due to acute folate deficiency despite normal folate erythrocyte level.

    PubMed

    Huguenin, Antoine; Barraud, Sara; Daliphard, Sylvie; Marot, Didier; Garnotel, Roselyne; Bani-Sadr, Firouzé

    2016-06-01

    We report the case of an alcoholic patient with severe pancytopenia with low plasma folate level but normal erythrocyte folates and cobalamin levels. The bone marrow smear concluded to a pancytopenia due to folates and/or cobalamin deficiency. Severe pancytopenia due to acute plasma folate deficiency can be observed despite normal erythrocyte folates level which reflects the organism's folates store. PMID:27108778

  3. Refractive properties of separate erythrocytes of Chernobyl clean-up workers at different pH

    NASA Astrophysics Data System (ADS)

    Mazarevica, Gunta; Freivalds, Talivaldis; Bruvere, Ruta; Gabruseva, Natalija; Leice, Alevtine; Zvagule, Tija

    2000-04-01

    This study is focused on the modifications in erythrocytes of Chernobyl nuclear power plant accident clean-up workers as a late health effect of short-term impact of high level radioactive contamination. As a result, a new method based on erythrocyte refractive index properties at different pH has been elaborated.

  4. Modulation of Erythrocyte Plasma Membrane Redox System Activity by Curcumin

    PubMed Central

    Singh, Prabhakar; Kesharwani, Rajesh Kumar; Misra, Krishna; Rizvi, Syed Ibrahim

    2016-01-01

    Plasma membrane redox system (PMRS) is an electron transport chain system ubiquitously present throughout all cell types. It transfers electron from intracellular substrates to extracellular acceptors for regulation of redox status. Curcumin, isolated from Curcuma longa, has modulatory effects on cellular physiology due to its membrane interaction ability and antioxidant potential. The present study investigates the effect of curcumin on PMRS activity of erythrocytes isolated from Wistar rats in vitro and in vivo and validated through an in silico docking simulation study using Molegro Virtual Docker (MVD). Effects of curcumin were also evaluated on level of glutathione (GSH) and the oxidant potential of plasma measured in terms of plasma ferric equivalent oxidative potentials (PFEOP). Results show that curcumin significantly (p < 0.01) downregulated the PMRS activity in a dose-dependent manner. Molecular docking results suggest that curcumin interacts with amino acids at the active site cavity of cytochrome b5 reductase, a key constituent of PMRS. Curcumin also increased the GSH level in erythrocytes and plasma while simultaneously decreasing the oxidant potential (PFEOP) of plasma. Altered PMRS activity and redox status are associated with the pathophysiology of several health complications including aging and diabetes; hence, the above finding may explain part of the role of curcumin in health beneficial effects. PMID:26904287

  5. The osmotic response of human erythrocytes and the membrane cytoskeleton.

    PubMed

    Heubusch, P; Jung, C Y; Green, F A

    1985-02-01

    The volumes of human erythrocytes suspended in solutions of varying concentrations of sodium chloride and sucrose were measured by a Coulter Channelyzer Model H4 with appropriate corrections. The cells showed greatly restricted volume changes at osmolarities between 200-700 mOsm. At osmolarities outside this limit, on the other hand, the cells showed nonrestricted volume changes following essentially the predictions of an ideal osmometer. This unexpected volume response was not spuriously due to changes in shape or to a changing orientation of the cells as they traversed the aperture. The restricted volume change observed was abolished when the cells had previously been treated with diamide or had been heated for 60 minutes at 50 degrees C, conditions that are known to disturb the spectrin-actin network. The possibility must be considered that the osmotic behavior of human erythrocytes may be nonideal and that this nonideal behavior is primarily due to mechanical restriction provided by the spectrin-actin network of the membrane cytoskeleton. PMID:3918046

  6. Modulation of Erythrocyte Plasma Membrane Redox System Activity by Curcumin.

    PubMed

    Singh, Prabhakar; Kesharwani, Rajesh Kumar; Misra, Krishna; Rizvi, Syed Ibrahim

    2016-01-01

    Plasma membrane redox system (PMRS) is an electron transport chain system ubiquitously present throughout all cell types. It transfers electron from intracellular substrates to extracellular acceptors for regulation of redox status. Curcumin, isolated from Curcuma longa, has modulatory effects on cellular physiology due to its membrane interaction ability and antioxidant potential. The present study investigates the effect of curcumin on PMRS activity of erythrocytes isolated from Wistar rats in vitro and in vivo and validated through an in silico docking simulation study using Molegro Virtual Docker (MVD). Effects of curcumin were also evaluated on level of glutathione (GSH) and the oxidant potential of plasma measured in terms of plasma ferric equivalent oxidative potentials (PFEOP). Results show that curcumin significantly (p < 0.01) downregulated the PMRS activity in a dose-dependent manner. Molecular docking results suggest that curcumin interacts with amino acids at the active site cavity of cytochrome b 5 reductase, a key constituent of PMRS. Curcumin also increased the GSH level in erythrocytes and plasma while simultaneously decreasing the oxidant potential (PFEOP) of plasma. Altered PMRS activity and redox status are associated with the pathophysiology of several health complications including aging and diabetes; hence, the above finding may explain part of the role of curcumin in health beneficial effects. PMID:26904287

  7. Proteomic identification of erythrocyte membrane protein deficiency in hereditary spherocytosis.

    PubMed

    Peker, Selen; Akar, Nejat; Demiralp, Duygu Ozel

    2012-03-01

    Hereditary spherocytosis (HS) is the most common congenital hemolytic anemia in Caucasians, with an estimated prevalence ranging from 1:2000 to 1:5000. The molecular defect in one of the erythrocytes (RBC) membrane proteins underlying HS like; spectrin-α, spectrin-β, ankyrin, band 3 and protein 4.2 that lead to membrane destabilization and vesiculation, may change the RBCs into denser and more rigid cells (spherocytes), which are removed by the spleen, leading to the development of hemolytic anemia. It is classified as mild, moderate and severe, according to the degree of the hemolytic anemia and the associated symptoms. Two-dimensional gel electrophoresis (2-DE) is potentially valuable method for studying heritable disorders as HS that involve membrane proteins. This separation technique of proteins based upon two biophysically unrelated parameters; molecular weight and charge, is a good option in clinical proteomics in terms of ability to separate complex mixtures, display post-translational modifications and changes after phosphorylation. In this study, we have used contemporary methods with some modifications for the solubilisation, separation and identification of erythrocyte membrane proteins in normal and in HS RBCs. Spectrin alpha and beta chain, ankyrin and band 3 proteins expression differences were found with PDQuest software 8.0.1. and peptide mass fingerprinting (PMF) analysis performed for identification of proteins in this study.

  8. Physicochemical characterization of artificial nanoerythrosomes derived from erythrocyte ghost membranes.

    PubMed

    Deák, Róbert; Mihály, Judith; Szigyártó, Imola Cs; Wacha, András; Lelkes, Gábor; Bóta, Attila

    2015-11-01

    Colloidal stabile nanoerythrosomes with 200 nm average diameter were formed from hemoglobin-free erythrocyte ghost membrane via sonication and membrane extrusion. The incorporation of extra lipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC), added to the sonicated ghosts, caused significant changes in the thermotropic character of the original membranes. As a result of the increased DPPC ratio the chain melting of the hydrated DPPC system and the characteristic small angle X-ray scattering (SAXS) of the lipid bilayers appeared. Significant morphological changes were followed by transmission electron microscopy combined with freeze fracture method (FF-TEM). After the ultrasonic treatment the large entities of erythrocyte ghosts transformed into nearly spherical nanoerythrosomes with diameters between 100 and 300 nm and at the same time a great number of 10-30 nm large membrane proteins or protein clusters were dispersed in the aqueous medium. The infrared spectroscopy (FT-IR) pointed out, that the sonication did not cause changes in the secondary structures of the membrane proteins under our preparation conditions. About fivefold of extra lipid--compared to the lipid content of the original membrane--caused homogeneous dispersion of nanoerythrosomes however the shape of the vesicles was not uniform. After the addition of about tenfold of DPPC, monoform and monodisperse nanoerythrosomes became typical. The outer surfaces of these roughly spherical objects were frequently polygonal, consisting of a net of pentagons and hexagons.

  9. Age related alterations of adrenoreceptor activity in erythrocyte membrane.

    PubMed

    Lomsadze, G; Khetsuriani, R; Arabuli, M; Intskirveli, N; Sanikidze, T

    2011-06-01

    The aim of the study was the investigation of age-related functional alterations of adrenoreceptors and the effect of agonist and antagonist drugs on age related adrenoreceptor activity in erythrocyte membrane. The impact of isopropanol and propanol on functional activity β- adrenergic receptors in red blood cell membrane were studied in 50 practically healthy men--volunteers. (I group--75-89 years old, II group--22-30 years old). The EPR signals S1 and S2 were registered in red blood cell membrane samples after incubation with isopropanol and propanol respectively. It was found that decreasing sensitivity (functional activity) of red blood cells membrane adrenoreceptors comes with aging (S1olderythrocyte could be a new therapeutic marker in the treatment different diseases.

  10. [Erythrocyte protoporphyrin during recovery from malnutrition in rats].

    PubMed

    Haydée Langini, S; Río de Gómez del Río, M E; Pita Martín de Portela, M L

    1999-09-01

    Interrelationships between Erythrocyte Protoporphyrin (EP), dietary Iron/Protein ratio (Fe/Prot) and Fe liver content (Feh) were studied during nutritional recovery in an experimental model: weanling female Wistar rats (To) were depleted with a protein-free diet (LP), losing 20% of their initial body weight. Then they were recovered until 45 days of age (T45) with diets containing: casein: 20 g/100 g; Fe (ammonium Fe citrate) (ppm.): 0, 75 or 100 (groups A1, A2 and A3, respectively). Hematocrit, Hemoglobin (Hb) (g/dL). Erythrocyte Protoporphyrin (EP) (microgram/dL Red Blood Cells) and Feh (microgram) were determined at To, LP and T45. Results were compared with control rats (C) fed with 20% of casein and Fe, 50 ppm. EP: a) decreased in C from To to T45 (99 +/- 24; 36 +/- 9; p < 0.01); b) increased in A1 and A2 at T45 (123 +/- 21; 93 +/- 29, respectively, p < 0.01) while A3 did not show significant difference (45 +/- 7) regarding to C: c) correlated inversely with Feh. According to the inverse correlation between EP and Fe/Prot (r = -0.99), we found that 92 ppm was an adequate Fe amount to prevent EP increase. These results confirm that during recovery from undernutrition EP depends on iron liver content, being an adequate indicator of iron nutritional status; therefore, EP would be useful as a predictor of the optimum Fe/Prot ratio for nutritional recovery.

  11. Evaluation of Hemagglutination Activity of Chitosan Nanoparticles Using Human Erythrocytes

    PubMed Central

    de Lima, Jefferson Muniz; Sarmento, Ronaldo Rodrigues; de Souza, Joelma Rodrigues; Brayner, Fábio André; Feitosa, Ana Paula Sampaio; Padilha, Rafael; Alves, Luiz Carlos; Porto, Isaque Jerônimo; Batista, Roberta Ferreti Bonan Dantas; de Oliveira, Juliano Elvis; de Medeiros, Eliton Souto; Bonan, Paulo Rogério Ferreti; Castellano, Lúcio Roberto

    2015-01-01

    Chitosan is a polysaccharide composed of randomly distributed chains of β-(1-4) D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L−1. The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS) collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH. PMID:25759815

  12. Evaluation of hemagglutination activity of chitosan nanoparticles using human erythrocytes.

    PubMed

    de Lima, Jefferson Muniz; Sarmento, Ronaldo Rodrigues; de Souza, Joelma Rodrigues; Brayner, Fábio André; Feitosa, Ana Paula Sampaio; Padilha, Rafael; Alves, Luiz Carlos; Porto, Isaque Jerônimo; Batista, Roberta Ferreti Bonan Dantas; de Oliveira, Juliano Elvis; de Medeiros, Eliton Souto; Bonan, Paulo Rogério Ferreti; Castellano, Lúcio Roberto

    2015-01-01

    Chitosan is a polysaccharide composed of randomly distributed chains of β-(1-4) D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L(-1). The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS) collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH.

  13. The Response of Duck Erythrocytes to Nonhemolytic Hypotonic Media

    PubMed Central

    Kregenow, Floyd M.

    1971-01-01

    Duck erythrocytes were incubated in hypotonic media at tonicities which do not produce hemolysis. The cells' response can be divided into two phases: an initial rapid phase of osmotic swelling and a second more prolonged phase (volume regulatory phase) in which the cells shrink until they approach their initial isotonic volume. Shrinkage associated with the volume regulatory phase is the consequence of a nearly isosmotic loss of KCl and water from the cell. The potassium loss results from a transient increase in K efflux. There is also a small reduction in Na permeability. Changes in cell size during the volume regulatory phase are not altered by 10-4 M ouabain although this concentration of ouabain does change the cellular cation content. The over-all response of duck erythrocytes is considered as an example of "isosmotic intracellular regulation," a term used to describe a form of volume regulation common to euryhaline invertebrates which is achieved by adjusting the number of effective intracellular osmotic particles. The volume regulatory phase is discussed as the product of a membrane mechanism which is sensitive to some parameter associated with cell volume and is capable of regulating the loss of potassium from the cell. This mechanism is able to regulate cell size when the Na-K exchange, ouabain-inhibitable pump mechanism is blocked. PMID:5112657

  14. Evaluation of hemagglutination activity of chitosan nanoparticles using human erythrocytes.

    PubMed

    de Lima, Jefferson Muniz; Sarmento, Ronaldo Rodrigues; de Souza, Joelma Rodrigues; Brayner, Fábio André; Feitosa, Ana Paula Sampaio; Padilha, Rafael; Alves, Luiz Carlos; Porto, Isaque Jerônimo; Batista, Roberta Ferreti Bonan Dantas; de Oliveira, Juliano Elvis; de Medeiros, Eliton Souto; Bonan, Paulo Rogério Ferreti; Castellano, Lúcio Roberto

    2015-01-01

    Chitosan is a polysaccharide composed of randomly distributed chains of β-(1-4) D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L(-1). The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS) collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH. PMID:25759815

  15. LIN28A Expression Reduces Sickling of Cultured Human Erythrocytes

    PubMed Central

    de Vasconcellos, Jaira F.; Fasano, Ross M.; Lee, Y. Terry; Kaushal, Megha; Byrnes, Colleen; Meier, Emily R.; Anderson, Molly; Rabel, Antoinette; Braylan, Raul; Stroncek, David F.; Miller, Jeffery L.

    2014-01-01

    Induction of fetal hemoglobin (HbF) has therapeutic importance for patients with sickle cell disease (SCD) and the beta-thalassemias. It was recently reported that increased expression of LIN28 proteins or decreased expression of its target let-7 miRNAs enhances HbF levels in cultured primary human erythroblasts from adult healthy donors. Here LIN28A effects were studied further using erythrocytes cultured from peripheral blood progenitor cells of pediatric subjects with SCD. Transgenic expression of LIN28A was accomplished by lentiviral transduction in CD34(+) sickle cells cultivated ex vivo in serum-free medium. LIN28A over-expression (LIN28A-OE) increased HbF, reduced beta (sickle)-globin, and strongly suppressed all members of the let-7 family of miRNAs. LIN28A-OE did not affect erythroblast differentiation or prevent enucleation, but it significantly reduced or ameliorated the sickling morphologies of the enucleated erythrocytes. PMID:25188417

  16. Altered erythrocyte Na-K pump in anorectic patients

    SciTech Connect

    Pasquali, R.; Strocchi, E.; Malini, P.; Casimirri, F.; Ambrosioni, E.; Melchionda, N.; Labo, G.

    1985-07-01

    The status of the erythrocyte sodium pump was evaluated in a group of patients suffering from anorexia nervosa and a group of healthy female control subjects. Anorectic patients showed significantly higher mean values of digoxin-binding sites/cell (ie, the number of Na-K-ATPase units) with respect to control subjects while no differences were found in the specific /sup 86/Rb uptake (which reflects the Na-K-ATPase activity) between the two groups. A significant correlation was found between relative weight and the number of Na-K-ATPase pump units (r = -0.66; P less than 0.0001). Anorectic patients showed lower serum T3 concentrations (71.3 +/- 53 ng/dL) with respect to control subjects (100.8 +/- 4.7 ng/dL; P less than 0.0005) and a significant negative correlation between T3 levels and the number of pump units (r = -0.52; P less than 0.003) was found. This study therefore shows that the erythrocyte Na-K pump may be altered in several anorectic patients. The authors suggest that this feature could be interrelated with the degree of underweight and/or malnutrition.

  17. The effect of retinyl palmitate added to iron-fortified maize porridge on erythrocyte incorporation of iron in African children with vitamin A deficiency.

    PubMed

    Davidsson, Lena; Adou, Pierre; Zeder, Christophe; Walczyk, Thomas; Hurrell, Richard

    2003-08-01

    Retinyl palmitate added to Fe-fortified maize bread has been reported to enhance Fe absorption in adult Venezuelan subjects but not in Western Europeans. It is not known to what extent these results were influenced by differences in vitamin A status of the study subjects. The objective of the present study was to evaluate the influence of retinyl palmitate added to Fe-fortified maize porridge on erythrocyte incorporation of Fe in children with vitamin A deficiency, before and after vitamin A supplementation. Erythrocyte incorporation of Fe-stable isotopes was measured 14 d after intake of maize porridge (2.0 mg Fe added as ferrous sulfate) with and without added retinyl palmitate (3.5 micromol; 3300 IU). The study was repeated 3 weeks after vitamin A supplementation (intake of a single dose of 210 micromol retinyl palmitate; 'vitamin A capsule'). Vitamin A status was evaluated by the modified relative dose-response (MRDR) technique. Retinyl palmitate added to the test meal reduced the geometric mean erythrocyte incorporation of Fe at baseline from 4.0 to 2.6 % (P=0.008, n 13; paired t test). At 3 weeks after vitamin A supplementation, geometric mean erythrocyte incorporation was 1.9 and 2.3 % respectively from the test meal with and without added retinyl palmitate (P=0.283). Mean dehydroretinol:retinol molar ratios were 0.156 and 0.125 before and after intake of the single dose of 210 micromol retinyl palmitate; 'vitamin A capsule' (P=0.15). In conclusion, retinyl palmitate added to the labelled test meals significantly decreased erythrocyte incorporation of Fe in children with vitamin A deficiency at baseline but had no statistically significant effect 3 weeks after vitamin A supplementation. The difference in response to retinyl palmitate added to Fe-fortified maize porridge on erythrocyte incorporation of Fe before and after intake of the vitamin A capsule indicates, indirectly, changes in vitamin A status not measurable by the MRDR technique. The lack of

  18. Oxidized low-density lipoprotein (Ox-LDL) impacts on erythrocyte viscoelasticity and its molecular mechanism.

    PubMed

    Wang, Xiang; Yang, Li; Liu, Yao; Gao, Wei; Peng, Weiyan; Sung, K-L Paul; Sung, Lanping Amy

    2009-10-16

    The oxidized low-density lipoprotein (Ox-LDL) plays an important role in atherosclerosis, yet it remains unclear if it damages circulating erythrocytes. In this study, erythrocyte deformability and its membrane proteins after Ox-LDL incubations are investigated by micropipette aspiration, thiol radical measurement, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Results show that Ox-LDL incubation reduces the erythrocyte deformability, decreases free thiol radical contents in erythrocytes, and induces the cross-linking among membrane proteins. SDS-PAGE analysis reveals a high molecular weight (HMW) complex as well as new bands between spectrins and band 3 and reduced ratios between band 3 and other major membrane skeletal proteins. Analyses indicate that Ox-LDL makes erythrocytes harder to deform through a molecular mechanism by which the oxidation of free thiol radicals forms disulfide bonds among membrane skeletal proteins.

  19. Recurrent fatal hydrops fetalis associated with a nucleotide substitution in the erythrocyte beta-spectrin gene.

    PubMed Central

    Gallagher, P G; Weed, S A; Tse, W T; Benoit, L; Morrow, J S; Marchesi, S L; Mohandas, N; Forget, B G

    1995-01-01

    We studied a kindred in which four third-trimester fetal losses occurred, associated with severe Coombs-negative hemolytic anemia and hydrops fetalis. Postmortem examination of two infants revealed extensive extramedullary erythropoiesis. Studies of erythrocytes and erythrocyte membranes from the parents revealed abnormal erythrocyte membrane mechanical stability as well as structural and functional abnormalities in spectrin, the principal structural protein of the erythrocyte membrane. Genetic studies identified a point mutation of the beta-spectrin gene, S2019P, in a region of beta spectrin that is critical for normal spectrin function. Both parents and two living children were heterozygous for this mutation; three infants dying of hydrops fetalis were homozygous for this mutation. In an in vitro assay using recombinant peptides, the mutant beta-spectrin peptide demonstrated a significant abnormality in its ability to interact with alpha spectrin. This is the first description of a molecular defect of the erythrocyte membrane associated with hydrops fetalis. Images PMID:7883966

  20. Two non-vesicular ATP release pathways in the mouse erythrocyte membrane

    PubMed Central

    Qiu, Feng; Wang, Junjie; Spray, David C.; Scemes, Eliana; Dahl, Gerhard

    2011-01-01

    Erythrocytes are exceptionally suited for analysis of non-exocytotic release mechanisms of ATP, because these cells under physiological conditions lack vesicles. Previous studies have indicated, that Pannexin1 (Panx1) provides a key ATP permeation pathway in many cell types, including human and frog erythrocytes. Here we show that erythrocytes of Panx1-/- mice lend further support to this conclusion. However, ATP release, although attenuated, was still observed in Panx1-/- mouse erythrocytes. In contrast to Panx1+/+ cells, this release was not correlated with uptake of extracellularly applied dyes, was insensitive to Panx1 channel blockers, and was inhibited by dipyridamole and stimulated by iloprost. Thus, in erythrocytes, two independent pathways mediate the release of ATP. We also show that glyburide is a strong inhibitor of Panx1 channels. PMID:21983290

  1. Production of erythrocyte autoantibodies in NZB mice is inhibited by CD4 antibodies.

    PubMed Central

    Oliveira, G G; Hutchings, P R; Roitt, I M; Lydyard, P M

    1994-01-01

    NZB mice spontaneously develop haemolytic anaemia as the result of production of erythrocyte autoantibodies. The mechanisms leading to breakdown in tolerance to erythrocyte autoantigens are unknown. Antibodies to CD4 have been successfully used to treat several murine models of autoimmune disease. In this study we injected NZB mice with non-depleting CD4 antibodies and were able to prevent and abrogate erythrocyte autoantibody production in young (Coombs' negative) and old (Coombs' positive) mice, respectively. Our data indicate the dependency of autoantibody production on CD4+ T cells. However, withdrawal of anti-CD4 antibodies resulted in the appearance of erythrocyte autoantibodies, showing that under these conditions we were unable to re-establish tolerance to autoantigens on erythrocytes using anti-CD4 treatment. PMID:8187337

  2. Effects of genistein and daidzein on erythrocyte membrane fluidity: an electron paramagnetic resonance study.

    PubMed

    Ajdzanović, Vladimir; Spasojević, Ivan; Filipović, Branko; Sosić-Jurjević, Branka; Sekulić, Milka; Milosević, Verica

    2010-04-01

    The maintenance of erythrocyte membrane fluidity at the physiological level is an important factor affecting the ability of erythrocytes to pass through blood vessels of small luminal diameter. Genistein and daidzein, which are used as alternative therapeutics in cardiovascular conditions, can be incorporated into the cell membrane and change its fluidity. The aim of this study was to examine the effects of genistein and daidzein on erythrocyte membrane fluidity at graded depths. We used electron paramagnetic resonance (EPR) spectroscopy and fatty acid spin probes (5-DS and 12-DS) where EPR spectra were dependent on fluidity. The results showed that genistein significantly (p < 0.05) decreased erythrocyte membrane fluidity near the hydrophilic surface, while daidzein significantly (p < 0.05) increased the same parameter in deeper regions of the membrane. These data suggest that the deep fluidizing effects of daidzein on erythrocyte membranes make it a better therapeutic choice than genistein in some cardiovascular conditions.

  3. Morphological Effects and Antioxidant Capacity of Solanum crispum (Natre) In Vitro Assayed on Human Erythrocytes.

    PubMed

    Suwalsky, Mario; Ramírez, Patricia; Avello, Marcia; Villena, Fernando; Gallardo, María José; Barriga, Andrés; Manrique-Moreno, Marcela

    2016-06-01

    In order to gain insight into the molecular mechanism of the antioxidant properties of Solanum crispum, aqueous extracts of its leaves were assayed on human erythrocytes and molecular models of its membrane. Phenolics and alkaloids were detected by HPLC-MS. Scanning electron and defocusing microscopy showed that S. crispum changed erythrocytes from the normal shape to echinocytes. These results imply that molecules present in the aqueous extracts were located in the outer monolayer of the erythrocyte membrane. Dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were chosen as representative of phospholipid classes located in the outer and inner monolayers of the erythrocyte membrane, respectively. X-ray diffraction showed that S. crispum preferentially interacted with DMPC bilayers. Experiments regarding its antioxidant properties showed that S. crispum neutralized the oxidative capacity of HClO on DMPE bilayers; defocusing microscopy and hemolysis assays demonstrated the protective effect of S. crispum against the oxidant effects of HClO on human erythrocytes. PMID:26809653

  4. Relationship between erythrocyte volume and cell age in humans and baboons. Technical report

    SciTech Connect

    Thompson, C.B.; Galli, R.L.; Melaragno, A.J.; Valeri, C.R.

    1983-03-30

    The relationship of red blood cell size to age during steady-state hematopoiesis has been studied using erythrocytes separated on the basis of size using counterflow centrifugation. The ratio of the age-related enzyme, erythrocyte glutamic oxaloacetic transferase (EGOT), to hemoglobin (Hb) increased progressively through the fractions, suggesting a correlation between erythrocyte volume and age. Reticulocytes, while present in all fractions, were selectively enriched in the larger subpopulations. To verify the biochemical evidence that erythrocytes decrease in volume with aging, in vivo cohort labeling of red blood cells with 59Fe was performed in baboons. A similar relationship of EGOT to Hb was observed to that in the human subpopulations. While a certain amount of erythrocyte volume heterogeneity seems to be present as a result of erythropoeisis, our data support the hypothesis that red blood cells decrease in volume as they age.

  5. A rapid method for counting nucleated erythrocytes on stained blood smears by digital image analysis

    USGS Publications Warehouse

    Gering, E.; Atkinson, C.T.

    2004-01-01

    Measures of parasitemia by intraerythrocytic hematozoan parasites are normally expressed as the number of infected erythrocytes per n erythrocytes and are notoriously tedious and time consuming to measure. We describe a protocol for generating rapid counts of nucleated erythrocytes from digital micrographs of thin blood smears that can be used to estimate intensity of hematozoan infections in nonmammalian vertebrate hosts. This method takes advantage of the bold contrast and relatively uniform size and morphology of erythrocyte nuclei on Giemsa-stained blood smears and uses ImageJ, a java-based image analysis program developed at the U.S. National Institutes of Health and available on the internet, to recognize and count these nuclei. This technique makes feasible rapid and accurate counts of total erythrocytes in large numbers of microscope fields, which can be used in the calculation of peripheral parasitemias in low-intensity infections.

  6. Serological Conservation of Parasite-Infected Erythrocytes Predicts Plasmodium falciparum Erythrocyte Membrane Protein 1 Gene Expression but Not Severity of Childhood Malaria.

    PubMed

    Warimwe, George M; Abdi, Abdirahman I; Muthui, Michelle; Fegan, Gregory; Musyoki, Jennifer N; Marsh, Kevin; Bull, Peter C

    2016-05-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), expressed on P. falciparum-infected erythrocytes, is a major family of clonally variant targets of naturally acquired immunity to malaria. Previous studies have demonstrated that in areas where malaria is endemic, antibodies to infected erythrocytes from children with severe malaria tend to be more seroprevalent than antibodies to infected erythrocytes from children with nonsevere malaria. These data have led to a working hypothesis that PfEMP1 variants associated with parasite virulence are relatively conserved in structure. However, the longevity of such serologically conserved variants in the parasite population is unknown. Here, using infected erythrocytes from recently sampled clinical P. falciparum samples, we measured serological conservation using pools of antibodies in sera that had been sampled 10 to 12 years earlier. The serological conservation of infected erythrocytes strongly correlated with the expression of specific PfEMP1 subsets previously found to be associated with severe malaria. However, we found no association between serological conservation per se and disease severity within these data. This contrasts with the simple hypothesis that P. falciparum isolates with a serologically conserved group of PfEMP1 variants cause severe malaria. The data are instead consistent with periodic turnover of the immunodominant epitopes of PfEMP1 associated with severe malaria.

  7. Heterologous desensitization of adenylate cyclase from pigeon erythrocytes under the action of the catalytic subunit of cAMP-dependent protein kinase

    SciTech Connect

    Popov, K.M.; Bulargina, T.V.; Severin, E.S.

    1985-09-20

    Preincubation of the plasma membranes from pigeon erythrocytes with the catalytic subunit of cAMP-dependent protein kinase leads to desensitization of adenylate cyclase of the erythrocytes. The adenylate cyclase activity, measured in the presence of 10 ..mu..M isoproterenol and 50 ..mu..M GTP-..gamma..-S, is decreased by 40% in 10 min of incubation, while the activity in the presence of 50 ..mu..M GTP-..gamma..-S is decreased by 35% in 20 min. The decrease in the adenylate cyclase activity is due to an increase in the lag phase of activation of the enzyme in the presence of a GTP analog stable to hydrolysis and a decrease in the activity in the steady-state phase of activation. Heterologous desensitization of adenylate cyclase under the action of cAMP-dependent protein kinase is coupled with a decrease in the number of ..beta..-adrenoreceptors capable of passing into a state of high affinity for antagonists in the absence of guanylic nucleotides. The influence of the catalytic subunit on adenylate cyclase entirely models the process of desensitization of the enzyme absorbed in the influence of isoproterenol or cAMP on erythrocytes.