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Sample records for clone 3d7 erythrocyte

  1. Limited cross-reactivity among domains of the Plasmodium falciparum clone 3D7 erythrocyte membrane protein 1 family

    DEFF Research Database (Denmark)

    Joergensen, Louise; Turner, Louise; Magistrado, Pamela

    2006-01-01

    The var gene-encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family is responsible for antigenic variation and sequestration of infected erythrocytes during malaria. We have previously grouped the 60 PfEMP1 variants of P. falciparum clone 3D7 into groups A and B/A (category A...

  2. The Plasmodium falciparum exported protein PF3D7_0402000 binds to erythrocyte ankyrin and band 4.1

    Energy Technology Data Exchange (ETDEWEB)

    Shakya, Bikash; Penn, Wesley D.; Nakayasu, Ernesto S.; Lacount, Douglas J.

    2017-09-01

    Plasmodium falciparum extensively modifies the infected red blood cell (RBC), resulting in changes in deformability, shape and surface properties. These alterations suggest that the RBC cytoskeleton is a major target for modification during infection. However, the molecular mechanisms leading to these changes are largely unknown. To begin to address this question, we screened for exported P. falciparum proteins that bound to the erythrocyte cytoskeleton proteins ankyrin 1 (ANK1) and band 4.1 (4.1R), which form critical interactions with other cytoskeletal proteins that contribute to the deformability and stability of RBCs. Yeast two-hybrid screens with ANK1 and 4.1R identified eight interactions with P. falciparum exported proteins, including an interaction between 4.1R and PF3D7_0402000 (PFD0090c). This interaction was first identified in a large-scale screen (Vignali et al., Malaria J, 7:211, 2008), which also reported an interaction between PF3D7_0402000 and ANK1. We confirmed the interactions of PF3D7_0402000 with 4.1R and ANK1 in pair-wise yeast two-hybrid and co-precipitation assays. In both cases, an intact PHIST domain in PF3D7_0402000 was required for binding. Complex purification followed by mass spectrometry analysis provided additional support for the interaction of PF3D7_0402000 with ANK1 and 4.1R. RBC ghost cells loaded with maltose-binding protein (MBP)-PF3D7_0402000 passed through a metal microsphere column less efficiently than mock- or MBP-loaded controls, consistent with an effect of PF3D7_0402000 on RBC rigidity or membrane stability. This study confirmed the interaction of PF3D7_0402000 with 4.1R in multiple independent assays, provided the first evidence that PF3D7_0402000 also binds to ANK1, and suggested that PF3D7_0402000 affects deformability or membrane stability of uninfected RBC ghosts.

  3. 3D7-derived Plasmodium falciparum erythrocyte membrane protein 1 is a frequent target of naturally acquired antibodies recognizing protein domains in a particular pattern independent of malaria transmission intensity

    DEFF Research Database (Denmark)

    Joergensen, Louise; Vestergaard, Lasse S; Turner, Louise

    2007-01-01

    in individuals living in the high transmission village and by the age of 2-4 years most individuals had Abs against most constructs. This level of reactivity was found at the age of 10-20 years in the medium transmission village and was never reached by individuals living under low transmission. Nevertheless...... derived from 3D7 in individuals living under markedly different malaria transmission intensity and were unable to find differences in the Ab acquisition rate to PfEMP1 of different groupings (A, B, or C) or domain type (alpha, beta, gamma, delta, epsilon, or x). Abs were acquired early in life......-parasite relationship factors operating at all transmission intensities....

  4. Phage display used for gene cloning of human recombinant antibody against the erythrocyte surface antigen, rhesus D

    DEFF Research Database (Denmark)

    Dziegiel, M; Nielsen, L K; Andersen, P S

    1995-01-01

    A novel phage display system has been developed for PCR amplification and cloning of the Fab fragments of human immunoglobulin genes. Using this system, we have cloned an antibody from a mouse-human hybridoma cell line directed against the erythrocyte antigen rhesus D. Intact erythrocytes were used...... for absorption of the Fab phages. Soluble Fab fragments produced from the cloned material showed identical performance to the parental antibody in agglutination assays. Gel filtration confirmed that the Fab fragment consists of a kappa-Fd heterodimer. The successful use of intact cells for selection of specific...

  5. Phage display used for gene cloning of human recombinant antibody against the erythrocyte surface antigen, rhesus D

    DEFF Research Database (Denmark)

    Dziegiel, Morten Hanefeld; Nielsen, L K; Andersen, P S

    1995-01-01

    A novel phage display system has been developed for PCR amplification and cloning of the Fab fragments of human immunoglobulin genes. Using this system, we have cloned an antibody from a mouse-human hybridoma cell line directed against the erythrocyte antigen rhesus D. Intact erythrocytes were used...... Fab phages demonstrates that it is possible to by-pass purification of the antigen of interest. Comparison with published germline sequences demonstrated that the immunoglobulin coding regions had the highest homology to the VH 1.9III and V kappa Hum kappa v325 germline genes, respectively....

  6. CD36 selection of 3D7 Plasmodium falciparum associated with severe childhood malaria results in reduced VAR4 expression

    Directory of Open Access Journals (Sweden)

    Hviid Lars

    2008-10-01

    Full Text Available Abstract Background A subset of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1SM is involved in the cytoadherence of P. falciparum-infected red blood cells (iRBC contributing to the pathogenesis of severe disease among young children in malaria endemic areas. The PfEMP1SM are encoded by group A var genes that are composed of a more constrained range of amino acid sequences than groups B and C var genes encoding PfEMP1UM associated with uncomplicated malaria. Also, unlike var genes from groups B and C, those from group A do not have sequences consistent with CD36 binding – a major cytoadhesion phenotype of P. falciparum isolates. Methods A 3D7 PfEMP1SM sub-line (3D7SM expressing VAR4 (PFD1235w/MAL8P1.207 was selected for binding to CD36. The protein expression of this parasite line was monitored by surface staining of iRBC using VAR4-specific antibodies. The serological phenotype of the 3D7SM parasites was determined by flow cytometry using malaria semi-immune and immune plasma and transcription of the 59 var genes in 3D7 were analysed by real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR using var-specific primers. Results A selection-induced increased adhesion of 3D7SM iRBC to CD36 resulted in a reduced var4 transcription and VAR4 surface expression. Conclusion VAR4 is not involved in CD36 adhesion. The current findings are consistent with the notion that CD36 adhesion is not associated with particular virulent parasite phenotypes, such as those believed to be exhibited by VAR4 expressing parasites.

  7. Evidence for erythrocyte-binding antigen 175 as a component of a ligand-blocking blood-stage malaria vaccine

    Science.gov (United States)

    Jiang, Lubin; Gaur, Deepak; Mu, Jianbing; Zhou, Hong; Long, Carole A.; Miller, Louis H.

    2011-01-01

    The ligands that pathogens use to invade their target cells have often proven to be good targets for vaccine development. However, Plasmodium falciparum has redundant ligands that mediate invasion of erythrocytes. The first requirement for the development of a successful ligand-blocking malaria vaccine is the demonstration that antibodies induced to each ligand can block the erythrocyte invasion of parasites with polymorphic sequences. Because of P. falciparum’s redundancy in erythrocyte invasion, each ligand needs to be studied under artificial conditions in which parasite invasion is restricted in its use of alternative pathways. Here we investigate the role of erythrocyte-binding antigen 175 (EBA-175), a parasite ligand that binds to sialic acid on glycophorin A, in the invasion of erythrocytes by 10 P. falciparum clones under conditions in which invasion is partially limited to the EBA-175–glycophorin A pathway, using chymotrypsin-treated erythrocytes. We show that the ability to invade erythrocytes for both sialic acid–independent and sialic acid–dependent pathways requires the EBA-175–glycophorin A pathway for erythrocyte invasion. Importantly, antibodies against region II of EBA-175 from the 3D7 clone blocked invasion of chymotrypsin-treated erythrocytes by >50% by all parasite clones studied, including those with multiple different mutations described in the literature. The one exception was FCR3, which had a similar sequence to 3D7 but only 30% inhibition of invasion of chymotrypsin-treated erythrocytes, indicating alternative pathways for invasion of chymotrypsin-treated erythrocytes. Our findings suggest that antibodies to region II of EBA-175, as one component of a ligand-blocking malaria vaccine, are largely unaffected by polymorphism in EBA-175. PMID:21502513

  8. In vitro antiplasmodial effiacy of mangrove plant, Ipomoea pes-caprae against Plasmodium falciparum (3D7 strain

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    Veera Venkata Satish Pothula

    2015-12-01

    Full Text Available Objective: To evaluate the antiplasmodial activity of mangrove plant, Ipomoea pes-caprae (I. pes-caprae (leaves, stems, flowers and roots against chloroquine-sensitive Plasmodium falciparum (3D7 strain (P. falciparum and cytotoxicity against brine shrimp larvae and THP-1 cell line. Methods: The plants (I. pes-caprae were collected from Machilipatnam mangrove forest (latitude 16°17′ N and longitude 81 °13′ E of Krishna District, Andhra Pradesh, India. Crude extracts from dried leaves, stems, flowers and roots of I. pes-caprae were prepared through Soxhlet extraction using methanol, chloroform, hexane, ethyl acetate and aqueous sequentially. These extracts were tested in vitro against P. falciparum (3D7 strain adopted in laboratory. The crude extracts were also tested for their cytotoxicity against brine shrimp larvae and THP-1 cell line. The phytochemical screenings were also conducted with standard methods. As the part of the study, the extracts were checked for any chemical injury to erythrocytes. Results: Out of these extracts, methanolic and aqueous extracts of all plant parts and chloroform extract of stems were active, and the ethyl acetate extracts were weekly active against P. falciparum. The extracts of chloroform (except stems and hexane were inactive. Amongst these extracts, the methanolic extract of root showed excellent antimalarial activity with the IC 50 value of 15.00 µg/mL. Cytotoxic evaluation revealed that methanolic, aqueous and ethyl acetate extracts were slightly cytotoxic whereas chloroform and hexane extracts were more toxic against brine shrimp. All extracts were non-toxic to THP-1 cells. The chemical injury to erythrocytes was also evaluated and it did not show any morphological changes in erythrocytes due to the effect of plant extracts of I. pes-caprae after 48 h of incubation. The phytochemical screening of the extracts revealed the presence of alkaloids, triterpenes, flavonoids, tannins, coumarins

  9. Cloning

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    Cloning describes the processes used to create an exact genetic replica of another cell, tissue or organism. ... named Dolly. There are three different types of cloning: Gene cloning, which creates copies of genes or ...

  10. A Bioinformatics Approach for Homology Modeling and Binding Site Identification of Triosephosphate Isomerase from Plasmodium falciparum 3D7

    National Research Council Canada - National Science Library

    Ullah, M; Hira, J; Ghosh, T; Ishaque, N; Absar, N

    2012-01-01

    .... The tertiary structure of triose phosphate isomerase of P. falciparum 3D7 was determined by means of homology modeling through multiple alignment followed by intensive optimization and validation...

  11. Cloning

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    ... such as the liver, brain and heart. Other consequences include premature aging and problems with the immune system. Another potential ... cell dies. This is part of the natural aging process that seems to happen in all cell types. As a consequence, clones created from a cell taken from an ...

  12. A Bioinformatics Approach for Homology Modeling and Binding Site Identification of Triosephosphate Isomerase from Plasmodium falciparum 3D7.

    Science.gov (United States)

    Ullah, M; Hira, J; Ghosh, T; Ishaque, N; Absar, N

    2012-10-01

    Malaria is a major public health concern, and malarial parasites have developed resistance against the commonly available drugs. So now a days it is a major concern to find out a new target for drug therapy. Plasmodium falciparum 3D7, one of the strains of plasmodium species also lacks in a functional tricarboxylic acid cycle and solely dependent on glycolysis for its energy supply like other plasmodium species. Although enzymes of malarial parasite have been considered as potential antimalarial drug targets, a little is known about their structural biology. The tertiary structure of triose phosphate isomerase of P. falciparum 3D7 was determined by means of homology modeling through multiple alignment followed by intensive optimization and validation. The modeling was done by Swiss-Model Workspace. The obtained model was verified with the structure validation programs such as, PROCHECK, Verify3D, and QMEAN for reliability. The verify3D value of 0.69 indicates that the environment profile of the model is good. A self-optimized prediction method with alignment or SOPMA is employed for calculation of the secondary structural features of triose phosphate isomerase. The secondary structure indicates that the predicted 3D structure of triosephosphate isomerase of P. falciparum 3D7 contains 48.37% α-helix, 29.27% random coil, and 16.67% extended strand. Active site determination through CASTp suggests that this protein can be utilized as a potential drug target. However, these will further be tested by wet lab studies for a targeted vaccine design against P. falciparum 3D7.

  13. A Bioinformatics Approach for Homology Modeling and Binding Site Identification of Triosephosphate Isomerase from Plasmodium falciparum 3D7

    OpenAIRE

    Ullah, M; Hira, J; Ghosh, T.; Ishaque, N.; Absar, N

    2012-01-01

    Malaria is a major public health concern, and malarial parasites have developed resistance against the commonly available drugs. So now a days it is a major concern to find out a new target for drug therapy. Plasmodium falciparum 3D7, one of the strains of plasmodium species also lacks in a functional tricarboxylic acid cycle and solely dependent on glycolysis for its energy supply like other plasmodium species. Although enzymes of malarial parasite have been considered as potential antimalar...

  14. The Phenolic Compound from Kalanchoe blossfeldiana (Crassulaceae Leaf and Its Antiplasmodial Activity against Plasmodium falciparum 3D7

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    Yenny Febriani Yun

    2016-08-01

    Full Text Available Various species of Kalanchoe plants have been widely used as raw materials in traditional medicines. This study was the continuation of the researches on secondary metabolites from Indonesia Kalanchoe plants, focused on Kalanchoe blossfeldiana. Fresh K. blossfeldiana leaf was extracted with methanol at room temperature to obtain the concentrated extract. The concentrated methanol extract was dissolved in water and then partitioned successively with n-hexane and ethyl acetate. The methanol, n-hexane, ethyl acetate extracts were tested using antiplasmodial assay against Plasmodium falciparum 3D7. The IC50 of methanol, n-hexane, and ethyl acetate extract were 13.002; 2.807, and 11 nM, respectively. Ethyl acetate extract was separated by the combination of chromatography on silica and ODS. This process produced the yellow solid. The chemical structure of the compound was determined based on UV, IR, MS, 1H-NMR, and 13C-NMR analyses and the comparison of data obtained from the literature and identified as phenolic compound, namely 3,3',4',5,7-pentahydroxyflavone or quercetin (1, and displayed antiplasmodial activity with IC50 3.97x10-2 nM.

  15. Strain induced magnetic anisotropy and 3d7 ions effect in CoFe2O4 nanoplatelets

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    Chandekar, Kamlesh V.; Kant, K. Mohan

    2017-11-01

    Cobalt ferrite (CoFe2O4) magnetic nanoplatelets were synthesized by hydrothermal method at 120 °C (H120) and 180 °C (H180) respectively. The formation of inverse spinel cobalt ferrite was confirmed by X- ray diffraction pattern (XRD) and Transmission electron microscopy (TEM). The X-ray diffraction studies shows the linear variation of microstrain with inverse crystallite size. The compressive microstrain of 0.024 and 0.016 was estimated for CoFe2O4 samples H120 and H180 respectively using Williamson-Hall (W-H) plot analysis assuming uniform deformation model. The valence state of metal ions and single phase formation single domain CoFe2O4 was confirmed by X-ray photoemission spectroscopy (XPS) and Raman spectroscopy. X-ray photoemission spectra (XPS) exhibit Fe 2p3/2 peak and Co 2p3/2 peaks in both samples composed of two peaks corresponding to octahedral sites and tetrahedral sites. The strain induced magnetic anisotropy is estimated on basis of strain measured by W-H plot at 300 K. The contribution of the Co2+ ions on octahedral sites of both samples of CoFe2O4 is assigned to the magnetostriction ions in cubic structure of cobalt ferrite by assuming ground state. The magnetic ions with 3d7 transition in CoFe2O4 lattice introduced the local magnetostriction through spin-orbit-lattice interaction with distorted cubic crystal field.

  16. The structure of Plasmodium falciparum 3D7_0606800 reveals a bi-lobed architecture that supports re-annotation as a Venus Flytrap protein.

    Science.gov (United States)

    Parker, Michelle L; Ramaswamy, Raghavendran; van Gordon, Kyle; Powell, Cameron J; Bosch, Jürgen; Boulanger, Martin J

    2017-09-01

    Plasmodium falciparum, the causative agent of malaria, employs a diverse array of surface displayed proteins to promote dissemination and establish infection in the human host. Of these, Pf3D7_0606800 is highly immunogenic and has been designated a potential top 10 candidate for inclusion in a multicomponent malarial vaccine. The role of Pf3D7_0606800 in parasite biology, however, is unknown and its characterization has been complicated by a lack of sequence identity with proteins of known structure or function. Towards elucidating Pf3D7_0606800 function, we determined its structure to a resolution of 2.35 Å using selenium single wavelength anomalous dispersion. A bi-lobed architecture displays the core structural hallmarks of Venus Flytrap (VFT) proteins prompting us to re-annotate Pf3D7_0606800 as PfVFT1. Structural analysis further revealed an extended inter-lobe groove that, when interrogated by molecular docking, appears well suited to bind peptide-based ligands. Collectively, our structural characterization of the highly antigenic P. falciparum surface protein PfVFT1 provides intriguing functional insight and establishes a structural template that could prove valuable for malaria vaccine engineering studies. © 2017 The Protein Society.

  17. Plasmodium Falciparum: Adhesion Phenotype of Infected Erythrocytes Using Classical and Mini-Column Cytoadherence Techniques

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    N Kalantari

    2013-03-01

    Full Text Available Background: Cytoadherence of Plasmodium falciparum- infected erythrocytes to host cells is an impor­tant trait for parasite survival and has a major role in pathology of malaria disease. Infections with P. falciparum usually consist of several subpopulations of parasites with different adhesive proper­ties. This study aimed to compare relative sizes of various binding subpopulations of different P. falciparum isolates. It also investigated the adhesive phenotype of a laboratory P. falciparum line, A4, using different binding techniques.Methods: Seven different P. falciparum isolates (ITG, A4, 3D7 and four field isolates were cultivated to late trophozoite and schizont and then cytoadherence to cell differentiation 36 (CD36, intercellu­lar cell adhesion molecule-1 (ICAM-1, and vascular cell adhesion molecule (V-CAM and E-selectin were examined. The relative binding sizes of parasite subpopulations to human receptors were meas­ured by mini-column cytoadherence method. The adhesion phenotype of P. falciparum-A4 line was evaluated by in vitro static, flow-based and mini-column binding assays.Results: The relative binding size of ITG, A4 and 3D7 clones to a column made with CHO/ICAM-1 was 68%, 54% and 0%, respectively. The relative binding sizes of these lines to CHO/CD36 were 59.7%, 28.7% and 0%, respectively. Different field isolates had variable sizes of respective CD36 and ICAM1-binding subpopulations. A4 line had five different subpopulations each with different binding sizes.Conclusion: This study provided further evidence that P. falciparum isolates have different binding subpopulations sizes in an infection. Furthermore, measurement of ICAM-1 or CD36 binding subpopula­tions may practical to study the cytoadherence phenotypes of P. falciparum field isolates at the molecular level.

  18. Erythrocyte deformability and erythrocyte aggregation in preeclampsia

    NARCIS (Netherlands)

    Pepple, D. J.; Hardeman, M. R.; Mullings, A. M.; Reid, H. L.

    2001-01-01

    One of the features of preeclampsia is impaired blood rheology due to altered erythrocyte aggregation and erythrocyte deformability. We investigated these two parameters which affect the viscosity of blood, along with serum and intraerythrocytic magnesium concentrations, immunoglobulin titres and

  19. Sub-grouping of Plasmodium falciparum 3D7 var genes based on sequence analysis of coding and non-coding regions

    DEFF Research Database (Denmark)

    Lavstsen, Thomas; Salanti, Ali; Jensen, Anja T R

    2003-01-01

    -grouped into three major groups (group A, B and C) and two intermediate groups B/A and B/C representing transitions between the three major groups. The best defined var group, group A, comprises telomeric genes transcribed towards the telomere encoding PfEMP1s with complex domain structures different from the 4...... and organization of the 3D7 PfEMP1 repertoire was investigated on the basis of the complete genome sequence. METHODS: Using two tree-building methods we analysed the coding and non-coding sequences of 3D7 var and rif genes as well as var genes of other parasite strains. RESULTS: var genes can be sub......-domain type dominant of groups B and C. Two sequences belonging to the var1 and var2 subfamilies formed independent groups. A rif subgroup transcribed towards the centromere was found neighbouring var genes of group A such that the rif and var 5' regions merged. This organization appeared to be unique...

  20. CD36 selection of 3D7 Plasmodium falciparum associated with severe childhood malaria results in reduced VAR4 expression

    DEFF Research Database (Denmark)

    Magistrado, Pamela; Staalsoe, Trine; Theander, Thor

    2008-01-01

    ABSTRACT: BACKGROUND: A subset of the Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1SM) is involved in the cytoadherence of P. falciparum-infected red blood cells (iRBC) contributing to the pathogenesis of severe disease among young children in malaria endemic areas. The PfEMP1SM...

  1. A new method for culturing Plasmodium falciparum shows replication at the highest erythrocyte densities

    Science.gov (United States)

    Li, Tao; Glushakova, Svetlana; Zimmerberg, Joshua

    2003-01-01

    Plasmodium falciparum replicates poorly in erythrocyte densities greater than a hematocrit of 20%. A new method to culture the major malaria parasite was developed by using a hollow fiber bioreactor that preserves healthy erythrocytes at hematocrit up to 100%. P. falciparum replicated equally well at all densities studied. This method proved advantageous for large-scale preparation of parasitized erythrocytes (and potentially immunogens thereof), because high yields ( approximately 10(10) in 4 days) could be prepared with less cost and labor. Concomitantly, secreted proteins were concentrated by molecular sieving during culture, perhaps contributing to the parasitemic limit of 8%-12% with the 3D7 strain. The finding that P. falciparum can replicate at packed erythrocyte densities suggests that this system may be useful for study of the pathogenesis of fatal cerebral malaria, of which one feature is densely packed blood cells in brain microvasculature.

  2. Hemoglobinopathic Erythrocytes Affect the Intraerythrocytic Multiplication of Plasmodium falciparum In Vitro

    Science.gov (United States)

    Glushakova, Svetlana; Balaban, Amanda; McQueen, Philip G.; Coutinho, Rosane; Miller, Jeffery L.; Nossal, Ralph; Fairhurst, Rick M.; Zimmerberg, Joshua

    2014-01-01

    Background. The mechanisms by which α-thalassemia and sickle cell traits confer protection from severe Plasmodium falciparum malaria are not yet fully elucidated. We hypothesized that hemoglobinopathic erythrocytes reduce the intraerythrocytic multiplication of P. falciparum, potentially delaying the development of life-threatening parasite densities until parasite clearing immunity is achieved. Methods. We developed a novel in vitro assay to quantify the number of merozoites released from an individual schizont, termed the “intraerythrocytic multiplication factor” (IMF). Results. P. falciparum (3D7 line) schizonts produce variable numbers of merozoites in all erythrocyte types tested, with median IMFs of 27, 27, 29, 23, and 23 in control, HbAS, HbSS, and α- and β-thalassemia trait erythrocytes, respectively. IMF correlated strongly (r2 = 0.97; P erythrocytes was confirmed using clinical parasite isolates with different IMFs. Mathematical modeling of the effect of IMF on malaria progression indicates that the lower IMF in thalassemia trait erythrocytes limits parasite density and anemia severity over the first 2 weeks of parasite replication. Conclusions. P. falciparum IMF, a parasite heritable virulence trait, correlates with erythrocyte indices and is reduced in thalassemia trait erythrocytes. Parasite IMF should be examined in other low-indices erythrocytes. PMID:24688070

  3. Storage of Erythrocytes Induces Suicidal Erythrocyte Death

    National Research Council Canada - National Science Library

    Lang, Elisabeth; Pozdeev, Vitaly I; Xu, Haifeng C; Shinde, Prashant V; Behnke, Kristina; Hamdam, Junnat M; Lehnert, Erik; Scharf, Rüdiger E; Lang, Florian; Häussinger, Dieter; Lang, Karl S; Lang, Philipp A

    2016-01-01

    .... In this study, we explored whether storage of RBC influences the rate of eryptosis. Flow cytometry was employed to quantify phosphatidylserine exposing erythrocytes from annexin V binding and cytosolic Ca2...

  4. Effect of the pre-erythrocytic candidate malaria vaccine RTS,S/AS01E on blood stage immunity in young children

    DEFF Research Database (Denmark)

    Bejon, Philip; Cook, Jackie; Bergmann-Leitner, Elke

    2011-01-01

    -linked immunosorbent assay, antibodies to 4 Plasmodium falciparum merozoite antigens (AMA-1, MSP-1(42), EBA-175, and MSP-3) and by growth inhibitory activity (GIA) using 2 parasite clones (FV0 and 3D7) at 4 times on 860 children who were randomized to receive with RTS,S/AS01(E) or a control vaccine. Results. Antibody......(See the article by Greenhouse et al, on pages 19-26.) Background. RTS,S/AS01(E) is the lead candidate malaria vaccine and confers pre-erythrocytic immunity. Vaccination may therefore impact acquired immunity to blood-stage malaria parasites after natural infection. Methods. We measured, by enzyme...... concentrations to AMA-1, EBA-175, and MSP-1(42) decreased with age during the first year of life, then increased to 32 months of age. Anti-MSP-3 antibody concentrations gradually increased, and GIA gradually decreased up to 32 months. Vaccination with RTS,S/AS01(E) resulted in modest reductions in AMA-1, EBA-175...

  5. What is Cloning?

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    Donate Home Cloning What is Cloning What is Cloning Clones are organisms that are exact genetic copies. ... clones made through modern cloning technologies. How Is Cloning Done? Many people first heard of cloning when ...

  6. Clofazimine Induced Suicidal Death of Human Erythrocytes

    National Research Council Canada - National Science Library

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

    2015-01-01

    .... In erythrocytes phospholipase A2 stimulates eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface...

  7. [Erythrocytic enzymopathy in Uzbekistan].

    Science.gov (United States)

    Bakhramov, S M; Ashrabhodzhaeva, K K

    2011-01-01

    Erythrocyte enzymes participate in the main interactions promoting utilization of glucose-glycolytic, pentosophosphate cycles and glutation system. In this report we study on erythrocyte G6PD deficiency which is the impairment related to the gender and expressed with development of acute drug-associated hemolytic anemia. Out of 13187 studied subjects 122 showed carrying of deficiency of erythrocyte G6PD activity, from them 98 (80.3%) subjects were male, and 24 (19.7%) female. As a whole, among the revealed in the population studies, and also verified in clinic of the persons with deficiency of erythrocyte G6PD there were marked different pathological phenotypes: hereditary nonspherecytary hemolytic anemia, acute drug-induced hemolytic anemia, asymptomatic gene carrying and, selected by us disease with few symptoms. As a whole, among the revealed in the population studies, and also verified in clinic of the persons with deficiency of erythrocyte G6PD there were marked different pathological phenotypes: hereditary nonspherecytary hemolytic anemia, acute drug-induced hemolytic anemia, asymptomatic gene carrying and, selected by us disease with few symptoms.

  8. ESR (Erythrocyte Sedimentation Rate) Test

    Science.gov (United States)

    ... products and services. Advertising & Sponsorship: Policy | Opportunities Erythrocyte Sedimentation Rate (ESR) Share this page: Was this page helpful? Also known as: Sed Rate; Sedimentation Rate; Westergren Sedimentation Rate Formal name: Erythrocyte Sedimentation ...

  9. Antigenic variation of Plasmodium knowlesi malaria: identification of the variant antigen on infected erythrocytes.

    OpenAIRE

    Howard, R J; Barnwell, J W; Kao, V

    1983-01-01

    Erythrocytes infected with mature asexual stages of Plasmodium knowlesi express a new surface antigen such that rhesus monkey antisera specifically agglutinate these cells. Cloned parasites can express different antigenic variants of this antigen. The variant antigen has been identified by comparison of the surface membrane antigens of a clone and of an antigenic variant of that clone of different agglutination phenotype. After lactoperoxidase labeling, 125I-labeled proteins of Mrs 210,000 an...

  10. Oxidative Hemolysis of Erythrocytes

    Science.gov (United States)

    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.

  11. Insect cells are superior to Escherichia coli in producing malaria proteins inducing IgG targeting PfEMP1 on infected erythrocytes

    DEFF Research Database (Denmark)

    Victor, Michala E; Bengtsson, Anja; Andersen, Gorm

    2010-01-01

    The PFD1235w Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigen is associated with severe malaria in children and can be expressed on the surface of infected erythrocytes (IE) adhering to ICAM1. However, the exact three-dimensional structure of this PfEMP1 and its surface...... PfEMP1 antigen expressed on 3D7PFD1235w-IE. Their recognition by human anti-malaria antibodies from previously infected Tanzanian donors was also analysed....

  12. Identification and characterization of a novel Plasmodium falciparum adhesin involved in erythrocyte invasion.

    Directory of Open Access Journals (Sweden)

    Nidhi Hans

    Full Text Available Malaria remains a major health problem worldwide. All clinical symptoms of malaria are attributed to the asexual blood stages of the parasite life cycle. Proteins resident in apical organelles and present on the surface of P. falciparum merozoites are considered promising candidates for the development of blood stage malaria vaccines. In the present study, we have identified and characterized a microneme associated antigen, PfMA [PlasmoDB Gene ID: PF3D7_0316000, PFC0700c]. The gene was selected by applying a set of screening criteria such as transcriptional upregulation at late schizogony, inter-species conservation and the presence of signal sequence or transmembrane domains. The gene sequence of PfMA was found to be conserved amongst various Plasmodium species. We experimentally demonstrated that the transcript for PfMA was expressed only in the late blood stages of parasite consistent with a putative role in erythrocyte invasion. PfMA was localized by immunofluorescence and immuno-electron microscopy to be in the micronemes, an apical organelle of merozoites. The functional role of the PfMA protein in erythrocyte invasion was identified as a parasite adhesin involved in direct attachment with the target erythrocyte. PfMA was demonstrated to bind erythrocytes in a sialic acid independent, chymotrypsin and trypsin resistant manner and its antibodies inhibited P. falciparum erythrocyte invasion. Invasion of erythrocytes is a complex multistep process that involves a number of redundant ligand-receptor interactions many of which still remain unknown and even uncharacterized. Our work has identified and characterized a novel P. falciparum adhesin involved in erythrocyte invasion.

  13. Identification and Characterization of a Novel Plasmodium falciparum Adhesin Involved in Erythrocyte Invasion

    Science.gov (United States)

    Hans, Nidhi; Singh, Shailja; Pandey, Alok K.; Reddy, K. Sony; Gaur, Deepak; Chauhan, Virander S.

    2013-01-01

    Malaria remains a major health problem worldwide. All clinical symptoms of malaria are attributed to the asexual blood stages of the parasite life cycle. Proteins resident in apical organelles and present on the surface of P. falciparum merozoites are considered promising candidates for the development of blood stage malaria vaccines. In the present study, we have identified and characterized a microneme associated antigen, PfMA [PlasmoDB Gene ID: PF3D7_0316000, PFC0700c]. The gene was selected by applying a set of screening criteria such as transcriptional upregulation at late schizogony, inter-species conservation and the presence of signal sequence or transmembrane domains. The gene sequence of PfMA was found to be conserved amongst various Plasmodium species. We experimentally demonstrated that the transcript for PfMA was expressed only in the late blood stages of parasite consistent with a putative role in erythrocyte invasion. PfMA was localized by immunofluorescence and immuno-electron microscopy to be in the micronemes, an apical organelle of merozoites. The functional role of the PfMA protein in erythrocyte invasion was identified as a parasite adhesin involved in direct attachment with the target erythrocyte. PfMA was demonstrated to bind erythrocytes in a sialic acid independent, chymotrypsin and trypsin resistant manner and its antibodies inhibited P. falciparum erythrocyte invasion. Invasion of erythrocytes is a complex multistep process that involves a number of redundant ligand-receptor interactions many of which still remain unknown and even uncharacterized. Our work has identified and characterized a novel P. falciparum adhesin involved in erythrocyte invasion. PMID:24058628

  14. Academic Cloning.

    Science.gov (United States)

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  15. Why Clone?

    Science.gov (United States)

    ... to clone agricultural animals, such as cattle and pigs, that are efficient producers of high-quality milk ... risks involved. Visit Teach.Genetics Cite this page Feedback Disclaimer Permissions Policy Privacy Policy Copyright © University of ...

  16. Cloning, clones and clonal disease.

    Science.gov (United States)

    Luzzatto, L

    2000-01-01

    In the past, cloning has been familiar to plant breeders because many plants can be easily reproduced in this way, bypassing the lengthy process of cross-fertilisation. Recently, the concept of cloning has become popular in human biology and medicine on two accounts. First, individual genes can be cloned from the enormous complexity of the DNA that makes up the human genetic material. It is expected that, within a few years, all the estimated 100,000 human genes will be isolated by this approach. This should make it possible to identify all the genes that determine the individual characteristics of human beings, including those responsible for causing human diseases or for making people more or less susceptible to pick up diseases from the environment. Cloned genes made into pharmaceutical products are already in use for treating a variety of diseases, from hormonal deficiencies to certain types of anaemia.

  17. Temporal expression and localization patterns of variant surface antigens in clinical Plasmodium falciparum isolates during erythrocyte schizogony.

    Directory of Open Access Journals (Sweden)

    Anna Bachmann

    Full Text Available Avoidance of antibody-mediated immune recognition allows parasites to establish chronic infections and enhances opportunities for transmission. The human malaria parasite Plasmodium falciparum possesses a number of multi-copy gene families, including var, rif, stevor and pfmc-2tm, which encode variant antigens believed to be expressed on the surfaces of infected erythrocytes. However, most studies of these antigens are based on in vitro analyses of culture-adapted isolates, most commonly the laboratory strain 3D7, and thus may not be representative of the unique challenges encountered by P. falciparum in the human host. To investigate the expression of the var, rif-A, rif-B, stevor and pfmc-2tm family genes under conditions that mimic more closely the natural course of infection, ex vivo clinical P. falciparum isolates were analyzed using a novel quantitative real-time PCR approach. Expression patterns in the clinical isolates at various time points during the first intraerythrocytic developmental cycle in vitro were compared to those of strain 3D7. In the clinical isolates, in contrast to strain 3D7, there was a peak of expression of the multi-copy gene families rif-A, stevor and pfmc-2tm at the young ring stage, in addition to the already known expression peak in trophozoites. Furthermore, most of the variant surface antigen families were overexpressed in the clinical isolates relative to 3D7, with the exception of the pfmc-2tm family, expression of which was higher in 3D7 parasites. Immunofluorescence analyses performed in parallel revealed two stage-dependent localization patterns of RIFIN, STEVOR and PfMC-2TM. Proteins were exported into the infected erythrocyte at the young trophozoite stage, whereas they remained inside the parasite membrane during schizont stage and were subsequently observed in different compartments in the merozoite. These results reveal a complex pattern of expression of P. falciparum multi-copy gene families during

  18. Human Cloning

    Science.gov (United States)

    2006-07-20

    research group, headed by Douglas Melton and Kevin Eggan, submitted their proposal to a Harvard committee composed of ethicists, scientists and public...United States. Although the company offered no proof of its claim, Dr . Brigette Boisselier, Managing Director of Clonaid, stated that genetic tests would...a year of the Dolly announcement, concerns over human cloning were heightened when Dr . Richard Seed, a Chicago scientist, announced on January 7

  19. Cytoadhesion to gC1qR through Plasmodium falciparum erythrocyte membrane protein 1 in severe malaria

    DEFF Research Database (Denmark)

    Magallón-Tejada, Ariel; Machevo, Sónia; Cisteró, Pau

    2016-01-01

    Cytoadhesion of Plasmodium falciparum infected erythrocytes to gC1qR has been associated with severe malaria, but the parasite ligand involved is currently unknown. To assess if binding to gC1qR is mediated through the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family, we analyzed...... by static binding assays and qPCR the cytoadhesion and var gene transcriptional profile of 86 P. falciparum isolates from Mozambican children with severe and uncomplicated malaria, as well as of a P. falciparum 3D7 line selected for binding to gC1qR (Pf3D7gC1qR). Transcript levels of DC8 correlated...... positively with cytoadhesion to gC1qR (rho = 0.287, P = 0.007), were higher in isolates from children with severe anemia than with uncomplicated malaria, as well as in isolates from Europeans presenting a first episode of malaria (n = 21) than Mozambican adults (n = 25), and were associated with an increased...

  20. Current status of erythrocyte substitutes.

    Science.gov (United States)

    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

  1. Agglutination of Mouse Erythrocytes by Eperythrozoon coccoides

    Science.gov (United States)

    Iralu, Vichazelhu; Ganong, Kevin D.

    1983-01-01

    Erythrocytes from blood of mice infected with Eperythrozoon coccoides for 3 or 4 days agglutinated spontaneously. Washed E. coccoides particles agglutinated washed erythrocytes of uninfected mice. E. coccoides-mediated agglutination of normal mouse erythrocytes would be an excellent system for studies of bacterial adhesion. Images PMID:6832825

  2. Agglutination of Mouse Erythrocytes by Eperythrozoon coccoides

    OpenAIRE

    Iralu, Vichazelhu; Ganong, Kevin D.

    1983-01-01

    Erythrocytes from blood of mice infected with Eperythrozoon coccoides for 3 or 4 days agglutinated spontaneously. Washed E. coccoides particles agglutinated washed erythrocytes of uninfected mice. E. coccoides-mediated agglutination of normal mouse erythrocytes would be an excellent system for studies of bacterial adhesion.

  3. [A physical model of gravitational erythrocyte sedimentation].

    Science.gov (United States)

    Losev, E S

    1992-01-01

    A model of erythrocyte sedimentation under gravity is proposed. The model is based on two-phase description of the blood and it involves a kinetic equation of erythrocyte aggregation. A method of characteristics is employed for analysing the physical pattern of sedimentation for different hematocrit. An approximate decision for trajectory of the interface between pure plasma and low-located region of the erythrocyte suspension is obtained. By utilizing this decision the simple coefficient of the erythrocyte aggregation ability calculated in terms of hematocrit and erythrocyte sedimentation rate is possible.

  4. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

    Directory of Open Access Journals (Sweden)

    Kriti Tyagi

    Full Text Available The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites.Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively.Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1 showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3 showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs for human erythrocyte receptors. However, the third protein (PkTRAg67.1 utilized the additional but different human erythrocyte receptor(s as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite.Recognition and sharing of human erythrocyte receptor(s by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

  5. Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi

    Science.gov (United States)

    Tyagi, Kriti; Gupta, Deepali; Saini, Ekta; Choudhary, Shilpa; Jamwal, Abhishek; Alam, Mohd. Shoeb; Zeeshan, Mohammad; Tyagi, Rupesh K.; Sharma, Yagya D.

    2015-01-01

    Background The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs) to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites. Methods Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively. Results Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1) showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3) showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs) for human erythrocyte receptors. However, the third protein (PkTRAg67.1) utilized the additional but different human erythrocyte receptor(s) as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite. Conclusions Recognition and sharing of human erythrocyte receptor(s) by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host. PMID:26393350

  6. Proliferation following tetraploidization regulates the size and number of erythrocytes in the blood flow during medaka development, as revealed by the abnormal karyotype of erythrocytes in the medaka TFDP1 mutant.

    Science.gov (United States)

    Taimatsu, Kiyohito; Takubo, Keiyo; Maruyama, Kouichi; Suda, Toshio; Kudo, Akira

    2015-05-01

    For the delivery of oxygen, the correct size/number of erythrocytes is required for proper blood flow. By combined analyses of wild-type (WT) medaka and the kyoho (kyo) mutant, we found proliferation-mediated adaptation for size/number of erythrocytes in the blood flow during medaka development. Before the start of heart beating in the WT medaka, the karyotype of erythrocytes was 2N-4N. After the start of blood flow, the karyotype changed to 4N-8N with tetraploidization, and the cell size became larger. After the start of intersegmental and pharyngeal blood flow, the erythrocytes became smaller. The medaka mutant kyo showed erythrocytes of large size, and positional cloning of kyo demonstrated the candidate gene TFDP1, indicating higher polyploidization due to arrest in S-phase in erythrocytes of the kyo mutant. From our findings, we uncovered a previously unrecognized system for the regulation of the size/number in the blood flow:proliferation of erythrocytes following tetraploidization during embryonic development. © 2015 Wiley Periodicals, Inc.

  7. Viscoelastic behavior of erythrocyte membrane.

    Science.gov (United States)

    Tözeren, A; Skalak, R; Sung, K L; Chien, S

    1982-07-01

    A nonlinear viscoelastic relation is developed to describe the viscoelastic properties of erythrocyte membrane. This constitutive equation is used in the analysis of the time-dependent aspiration of an erythrocyte membrane into a micropipette. Equations governing this motion are reduced to a nonlinear integral equation of the Volterra type. A numerical procedure based on a finite difference scheme is used to solve the integral equation and to match the experimental data. The data, aspiration length vs. time, is used to determine the relaxation function at each time step. The inverse problem of obtaining the time dependence of the aspiration length from a given relaxation function is also solved. Analytical results obtained are applied to the experimental data of Chien et al. 1978. Biophys. J. 24:463-487. A relaxation function similar to that of a four-parameter solid with a shear-thinning viscous term is proposed.

  8. Agglutination of human O erythrocytes by influenza A(H1N1) viruses freshly isolated from patients.

    Science.gov (United States)

    Murakami, T; Haruki, K; Seto, Y; Kimura, T; Minoshiro, S; Shibe, K

    1991-04-01

    The hemagglutinin titers of 10 influenza A (H1N1) viruses were examined using the erythrocytes of several species. Human O erythrocytes showed the highest agglutination titer to the viruses, whereas chicken erythrocytes showed a low titer. These findings were noted for at least 10 passages by serial dilutions of the viruses in Madin-Darby canine kidney (MDCK) cells. All influenza A(H1N1) viruses, plaque-cloned directly from throat-washing specimens of patients, also agglutinated human O but not chicken erythrocytes. The results of a hemadsorption test indicated that chicken erythrocytes possess less affinity to MDCK cells infected with the A/Osaka City/2/88(H1N1) stain than to those infected with the A/Yamagata/120/86(H1N1) strain which is used as an inactivated influenza vaccine in Japan. However, there were no significant differences between the A/Osaka City/2/88 and the A/Yamagata/120/86 strains in the hemagglutination inhibition test. Since human O erythrocytes have high agglutination activity to influenza A(H1N1) and also to A(H3N2) and B viruses in MDCK cells, these erythrocytes may be useful for the serological diagnosis of influenza.

  9. Spectroscopic analysis of irradiated erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Selim, Nabila S. [Biophysics Lab, Radiation Physics Department, National Center for Radiation Research and Technology (NCRRT), AEA, P.O. Box 29, Madinat Nasr, Cairo (Egypt); Desouky, Omar S., E-mail: omardesouky@yahoo.com [Biophysics Lab, Radiation Physics Department, National Center for Radiation Research and Technology (NCRRT), AEA, P.O. Box 29, Madinat Nasr, Cairo (Egypt); Ismail, Nagla M.; Dakrory, Amira Z. [Physics Department, Faculty of Girls for Arts, Sciences and Education, Ain Shams University, Cairo (Egypt)

    2011-12-15

    The aim of the present work is to study the effect of gamma radiation on the lipid part of the erythrocyte membrane, and to test the efficiency of lipoic acid as a radioprotector. This effect was evaluated using electron paramagnetic resonance (EPR), and Fourier transform infrared (FT-IR) spectroscopy. The results showed an increase in the number of spin density by 14%, 22% and 65% after exposure to 25, 50 and 100 Gy respectively; whereas there was a decline in the obtained density after incubation with lipoic acid by a factor of approximately 32%. The FT-IR spectra of the irradiated erythrocytes samples showed a marked decrease in the intensity of all characteristic peaks, which increased as the irradiation dose increased. The second-derivative of these spectra, allow the conformationally sensitive membrane acyl chain methylene stretching modes to be separated from the protein (mostly hemoglobin) vibrations that dominate the spectra of intact cells. The 2850 cm{sup -1} band showed changes in the band shape and position after exposure to 50 and 100 Gy. Therefore it can be concluded that the band at 2850 cm{sup -1} only is useful in monitoring the radiation effect of the lipids cell membrane intact cells. - Highlights: > Effect of {gamma} radiation on erythrocyte membrane was studied using EPR and FT-IR. > Efficiency of {alpha}-lipoic acid as radioprotector was tested. > Lipoic acid diminished the free radicals number after gamma irradiation by 32%. > FT-IR spectra of the irradiated erythrocyte showed a decrease in their intensity. > Lipoic acid enhances the membrane to resist the action of gamma radiation.

  10. Effects of nickel chloride on the erythrocytes and erythrocyte immune adherence function in broilers.

    Science.gov (United States)

    Li, Jian; Wu, Bangyuan; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Wang, Xun; Tang, Kun; Yin, Shuang

    2014-11-01

    This study was conducted to investigate the immune adherence function of erythrocytes and erythrocyte induced by dietary nickel chloride (NiCl2) in broilers fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl2 for 42 days. Blood samples were collected from five broilers in each group at 14, 28, and 42 days of age. Changes of erythrocyte parameters showed that total erythrocyte count (TEC), hemoglobin (Hb) contents, and packed cell volume (PCV) were significantly lower (p erythrocyte osmotic fragility (EOF) was higher (p erythrocyte immune adherence function indicated that erythrocyte C3b receptor rosette rate (E-C3bRR) was significantly decreased (p erythrocyte immune complex rosette rate (E-ICRR) was markedly increased (p erythrocytic integrity, erythrocytic ability to transport oxygen, and erythrocyte immune adherence function in broilers. Impairment of the erythrocytes and erythrocyte immune adherence function was one of main effect mechanisms of NiCl2 on the blood function.

  11. Human cloning 2001.

    Science.gov (United States)

    Healy, David L; Weston, Gareth; Pera, Martin F; Rombauts, Luk; Trounson, Alan O

    2002-05-01

    This review summaries human cloning from a clinical perspective. Natural human clones, that is, monozygotic twins, are increasing in the general community. Iatrogenic human clones have been produced for decades in infertile couples given fertility treatment such as ovulation induction. A clear distinction must be made between therapeutic cloning using embryonic stem cells and reproductive cloning attempts. Unlike the early clinical years of in vitro fertilization, with cloning there is no animal model that is safe and dependable. Until there is such a model, 'Dolly'-style human cloning is medically unacceptable.

  12. Cloning of observables

    OpenAIRE

    Ferraro, Alessandro; Galbiati, Matteo; Paris, Matteo G. A.

    2005-01-01

    We introduce the concept of cloning for classes of observables and classify cloning machines for qubit systems according to the number of parameters needed to describe the class under investigation. A no-cloning theorem for observables is derived and the connections between cloning of observables and joint measurements of noncommuting observables are elucidated. Relationships with cloning of states and non-demolition measurements are also analyzed.

  13. [AGGREGATION OF METABOLICALLY DEPLETED HUMAN ERYTHROCYTES].

    Science.gov (United States)

    Sheremet'ev, Yu A; Popovicheva, A N; Rogozin, M M; Levin, G Ya

    2016-01-01

    An aggregation of erythrocytes in autologous plasma after blood storage for 14 days at 4 °C was studied using photometry and light microscopy. The decrease of ATP content, the formation of echinocytes and spheroechinocytes, the decrease of rouleaux form of erythrocyte aggregation were observed during the storage. On the other hand the aggregates of echinocytes were formed in the stored blood. The addition of plasma from the fresh blood didn't restore the normal discocytic shape and aggregation of erythrocytes in the stored blood. The possible mechanisms of erythrocytes and echinocytes aggregation are discussed.

  14. Patulin-induced suicidal erythrocyte death

    National Research Council Canada - National Science Library

    Lupescu, Adrian; Jilani, Kashif; Zbidah, Mohanad; Lang, Florian

    2013-01-01

    .... Similar to apoptosis of nucleated cells, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by cell membrane scrambling leading to phosphatidylserine...

  15. Cloning of the repertoire of individual Plasmodium falciparum var genes using transformation associated recombination (TAR.

    Directory of Open Access Journals (Sweden)

    Annette Gaida

    Full Text Available One of the major virulence factors of the malaria causing parasite is the Plasmodium falciparum encoded erythrocyte membrane protein 1 (PfEMP1. It is translocated to It the membrane of infected erythrocytes and expressed from approximately 60 var genes in a mutually exclusive manner. Switching of var genes allows the parasite to alter functional and antigenic properties of infected erythrocytes, to escape the immune defense and to establish chronic infections. We have developed an efficient method for isolating VAR genes from telomeric and other genome locations by adapting transformation-associated recombination (TAR cloning, which can then be analyzed and sequenced. For this purpose, three plasmids each containing a homologous sequence representing the upstream regions of the group A, B, and C var genes and a sequence homologous to the conserved acidic terminal segment (ATS of var genes were generated. Co-transfection with P. falciparum strain ITG2F6 genomic DNA in yeast cells yielded 200 TAR clones. The relative frequencies of clones from each group were not biased. Clones were screened by PCR, as well as Southern blotting, which revealed clones missed by PCR due to sequence mismatches with the primers. Selected clones were transformed into E. coli and further analyzed by RFLP and end sequencing. Physical analysis of 36 clones revealed 27 distinct types potentially representing 50% of the var gene repertoire. Three clones were selected for sequencing and assembled into single var gene containing contigs. This study demonstrates that it is possible to rapidly obtain the repertoire of var genes from P. falciparum within a single set of cloning experiments. This technique can be applied to individual isolates which will provide a detailed picture of the diversity of var genes in the field. This is a powerful tool to overcome the obstacles with cloning and assembly of multi-gene families by simultaneously cloning each member.

  16. Cloning of the repertoire of individual Plasmodium falciparum var genes using transformation associated recombination (TAR).

    Science.gov (United States)

    Gaida, Annette; Becker, Marion M; Schmid, Christoph D; Bühlmann, Tobias; Louis, Edward J; Beck, Hans-Peter

    2011-03-07

    One of the major virulence factors of the malaria causing parasite is the Plasmodium falciparum encoded erythrocyte membrane protein 1 (PfEMP1). It is translocated to It the membrane of infected erythrocytes and expressed from approximately 60 var genes in a mutually exclusive manner. Switching of var genes allows the parasite to alter functional and antigenic properties of infected erythrocytes, to escape the immune defense and to establish chronic infections. We have developed an efficient method for isolating VAR genes from telomeric and other genome locations by adapting transformation-associated recombination (TAR) cloning, which can then be analyzed and sequenced. For this purpose, three plasmids each containing a homologous sequence representing the upstream regions of the group A, B, and C var genes and a sequence homologous to the conserved acidic terminal segment (ATS) of var genes were generated. Co-transfection with P. falciparum strain ITG2F6 genomic DNA in yeast cells yielded 200 TAR clones. The relative frequencies of clones from each group were not biased. Clones were screened by PCR, as well as Southern blotting, which revealed clones missed by PCR due to sequence mismatches with the primers. Selected clones were transformed into E. coli and further analyzed by RFLP and end sequencing. Physical analysis of 36 clones revealed 27 distinct types potentially representing 50% of the var gene repertoire. Three clones were selected for sequencing and assembled into single var gene containing contigs. This study demonstrates that it is possible to rapidly obtain the repertoire of var genes from P. falciparum within a single set of cloning experiments. This technique can be applied to individual isolates which will provide a detailed picture of the diversity of var genes in the field. This is a powerful tool to overcome the obstacles with cloning and assembly of multi-gene families by simultaneously cloning each member.

  17. Erythrocyte Sedimentation Rate (ESR): MedlinePlus Lab Test Information

    Science.gov (United States)

    ... this page: https://medlineplus.gov/labtests/erythrocytesedimentationrateesr.html Erythrocyte Sedimentation Rate (ESR) To use the sharing features ... this page, please enable JavaScript. What is an Erythrocyte Sedimentation Rate (ESR)? An erythrocyte sedimentation rate (ESR) ...

  18. Cloning and characterisation of the Pasteurella multocida ahpA gene responsible for a haemolytic phenotype in Escherichia coli.

    Science.gov (United States)

    Cox, A J; Hunt, M L; Ruffolo, C G; Adler, B

    2000-03-01

    Haemolysins are membrane-damaging agents which have been described as bacterial virulence factors due to their ability to lyse erythrocytes and other host cells, and therefore inducing a greater inflammatory response (Elliott et al., 1998). Pasteurella multocida was found to be haemolytic under anaerobic conditions. In this study, we cloned and characterised a P. multocida gene, designated ahpA, which conferred a haemolytic phenotype on Escherichia coli when incubated under anaerobic conditions. A deletion was introduced into the ahpA open reading frame which abolished the haemolytic phenotype. The clone containing ahpA showed erythrocyte specificity, causing haemolysis of bovine and equine erythrocytes, and demonstrated weak haemolysis on ovine erythrocytes. Upon further investigation, AhpA was found to affect the expression of the E. coli K-12 latent haemolysin, SheA, under anaerobic conditions.

  19. Invasion of erythrocytes by Babesia bovis

    NARCIS (Netherlands)

    Gaffar, Fasila Razzia

    2004-01-01

    In this thesis we investigated the invasion of erythrocytes taking place during the asexual erythrocytic blood stage of the apicomplexan parasites Babesia bovis parasite. Host cell invasion by apicomplexan parasites is a complex process requiring multiple receptor-ligand interactions, involving

  20. Comparative Erythrocytes Osmotic Fragility Test and some ...

    African Journals Online (AJOL)

    Erythrocytes with HbSS type showed corpuscular haemaglobin concentration that was significantly lower than HbAA and HbAS (p < 0.0001); mean values of HbAA and HbAS did not show any significant difference. In contrast, HbAA erythrocytes showed mean corpuscular volume (MCV) value that was significantly lower ...

  1. Short Communication Erythrocytic parameters as indicators for ...

    African Journals Online (AJOL)

    Short Communication Erythrocytic parameters as indicators for differentiating between the pregnant and pseudopregnant bitches in Nigeria. ... The trend of decrease in PCV and Hb values were not observed in the bitches with pseudopregnancy. This shows that these erythrocytic parameters can be used to detect and ...

  2. Empirical Results on Cloning and Clone Detection

    OpenAIRE

    Wagner, Stefan

    2015-01-01

    Cloning means the use of copy-paste as method in developing software artefacts. This practice has several problems, such as unnecessary increase of these artefacts, and thereby increased comprehension and change efforts, as well as potential inconsistencies. The automatic detection of clones has been a topic for research for several years now and we have made huge progress in terms of precision and recall. This led to a series of empirical analyses we have performed on the effects and the amo...

  3. Application of Mammalian Erythrocytes as Indicators for Newcastle ...

    African Journals Online (AJOL)

    In this study, the potential of heterologous erythrocyte indicator systems for detecting Newcastle Disease (ND) antibodies was investigated using donkey, horse, dog and pig erythrocytes while guinea pig erythrocyte served as the control for comparison. Previous research had shown that guinea pig erythrocyte is useful as ...

  4. [Lysophosphatidic acid and human erythrocyte aggregation].

    Science.gov (United States)

    Sheremet'ev, Iu A; Popovicheva, A N; Levin, G Ia

    2014-01-01

    The effects of lysophosphatidic acid on the morphology and aggregation of human erythrocytes has been studied. Morphology of erythrocytes and their aggregates were studied by light microscopy. It has been shown that lysophosphatidic acid changes the shape of red blood cells: diskocyte become echinocytes. Aggregation of red blood cells (rouleaux) was significantly reduced in autoplasma. At the same time there is a strong aggregation of echinocytes. This was accompanied by the formation of microvesicles. Adding normal plasma to echinocytes restores shape and aggregation of red blood cells consisting of "rouleaux". A possible mechanism of action of lysophosphatidic acid on erythrocytes is discussed.

  5. Enzymatic assay for methotrexate in erythrocytes

    DEFF Research Database (Denmark)

    Schrøder, H; Heinsvig, E M

    1985-01-01

    Methotrexate (MTX) accumulates in erythrocytes in MTX-treated patients. We present a modified enzymatic assay measuring MTX concentrations between 10 and 60 nmol/l in erythrocytes, adapted for a centrifugal analyser (Cobas Bio). About 40 patient's samples could be analysed within 1 h. The detection...... limit was 3 nmol/l. Within run and between-run precision was 7.4% and 13.5% for control 10 nmol/l and 1.2% and 3.2% for control 50 nmol/l. Recovery was 85-115% of MTX added to haemolysed erythrocytes. We found the method useful for pharmacokinetic studies of MTX in erythrocytes in MTX-treated patients...

  6. Induction of Suicidal Erythrocyte Death by Nelfinavir

    Directory of Open Access Journals (Sweden)

    Rosi Bissinger

    2015-05-01

    Full Text Available 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.

  7. Quantitation of CD55 and CD59 expression on reticulocytes and mature erythrocytes in paroxysmal nocturnal hemoglobinuria, aplastic anemia, and healthy control subjects.

    Science.gov (United States)

    Kim, Yeongsic; Lim, Jihyang; Kim, Myungshin; Kim, Yonggoo; Lee, Jong-Wook; Han, Kyungja

    2010-01-01

    Since PNH occasionally results in bone marrow failure, it is difficult to differentiate PNH from AA with small numbers of CD(55) (-)CD(59) (-) erythrocytes. We quantified CD55 and CD59 molecules expressed on normal reticulocytes and mature erythrocytes of paroxysmal nocturnal hemoglobinuria (PNH), aplastic anemia (AA), and normal individuals in order to determine their usefulness for differentiation between PNH and AA. A total of 56 patients (AA 39 patients, PNH 17 patients) and 10 healthy volunteers were enrolled. Two-color flow cytometric analyses were conducted using thiazole orange, anti-CD55 and CD59 monoclonal antibodies to identify CD(55) (-)CD(59) (-) reticulocytes and mature erythrocytes. Mean fluorescence level of CD(55) (+) mature erythrocytes was lowest in the PNH patients (13.2 x 10(3) MESF), and was significantly lower than in normal controls (16.7 x 10(3) MESF, p erythrocytes was lowest in the PNH subjects (24.5 x 10(3) MESF), significantly less than in normal controls (39.0 x 10(3) MESF, p erythrocytes may be useful in differentiating PNH from AA patients with small numbers of PNH-phenotype erythrocytes, and the total reticulocyte count may prove useful as a marker for PNH clone size.

  8. Statement on Human Cloning

    Science.gov (United States)

    ... as our understanding of this technology advances. Support Stem Cell Research (including Research Cloning) AAAS supports stem cell research, including the use of nuclear transplantation techniques (also ...

  9. Gateway Recombinational Cloning.

    Science.gov (United States)

    Reece-Hoyes, John S; Walhout, Albertha J M

    2018-01-02

    The Gateway recombinatorial cloning system was developed for cloning multiple DNA fragments in parallel (e.g., in 96-well formats) in a standardized manner using the same enzymes. Gateway cloning is based on the highly specific integration and excision reactions of bacteriophage λ into and out of the Escherichia coli genome. Because the sites of recombination (" att " sites) are much longer (25-242 bp) than restriction sites, they are extremely unlikely to occur by chance in DNA fragments. Therefore, the same recombination enzyme can be used to robustly clone many different fragments of variable size in parallel reactions. © 2018 Cold Spring Harbor Laboratory Press.

  10. Stimulation of Erythrocyte Death by Phloretin

    Directory of Open Access Journals (Sweden)

    Rosi Bissinger

    2014-12-01

    Full Text Available Background: Phloretin, a natural component of apples, pears and strawberries, has previously been shown to stimulate apoptosis of nucleated cells. Erythrocytes may similarly enter suicidal death or eryptosis, which is characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i, ceramide, ATP depletion, and activation of protein kinase C (PKC as well as p38 mitogen activated protein kinase (p38 kinase. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, and ceramide abundance from binding of specific antibodies. Results: A 48 h exposure of human erythrocytes to phloretin significantly increased the percentage of annexin-V-binding cells (≥100 µM without significantly influencing forward scatter. Phloretin did not significantly modify [Ca2+]i and the stimulation of annexin-V-binding by phloretin (300 µM did not require presence of extracellular Ca2+. Phloretin did not significantly modify erythrocyte ATP levels, and the effect of phloretin on annexin-V-binding was not significantly altered by PKC inhibitor staurosporine (1 µM or p38 kinase inhibitor SB2203580 (2 µM. However, phloretin significantly increased the ceramide abundance at the cell surface. Conclusions: Phloretin stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect at least partially due to up-regulation of ceramide abundance.

  11. Bile Acid-Induced Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Elisabeth Lang

    2016-04-01

    Full Text Available Background/Aims: In nucleated cells, bile acids may activate cation channels subsequently leading to entry of Ca2+. In erythrocytes, increase of cytosolic Ca2+ activity triggers eryptosis, the suicidal death of erythrocytes characterized by phosphatidylserine exposure at the cell surface and cell shrinkage. Eryptosis is triggered by bile duct ligation, an effect partially attributed to conjugated bilirubin. The present study explored, whether bile acids may stimulate eryptosis. Methods: Phosphatidylserine exposing erythrocytes have been identified utilizing annexin V binding, cell volume estimated from forward scatter, cytosolic Ca2+ activity determined using Fluo-3 fluorescence, and ceramide abundance at the erythrocyte surface utilizing specific antibodies. Results: The exposure of human erythrocytes to glycochenodesoxycholic (GCDC and taurochenodesoxycholic (TCDC acid was followed by a significant decrease of forward scatter and significant increase of Fluo-3 fluorescence, ceramide abundance as well as annexin V binding. The effect on annexin V binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusion: Bile acids stimulate suicidal cell death, an effect paralleled by and in part due to Ca2+ entry and ceramide. The bile acid induced eryptosis may in turn lead to accelerated clearance of circulating erythrocytes and, thus, may contribute to anemia in cholestatic patients.

  12. Characterization of carrier erythrocytes for biosensing applications

    Science.gov (United States)

    Bustamante López, Sandra C.; Meissner, Kenith E.

    2017-09-01

    Erythrocyte abundance, mobility, and carrying capacity make them attractive as a platform for blood analyte sensing as well as for drug delivery. Sensor-loaded erythrocytes, dubbed erythrosensors, could be reinfused into the bloodstream, excited noninvasively through the skin, and used to provide measurement of analyte levels in the bloodstream. Several techniques to load erythrocytes, thus creating carrier erythrocytes, exist. However, their cellular characteristics remain largely unstudied. Changes in cellular characteristics lead to removal from the bloodstream. We hypothesize that erythrosensors need to maintain native erythrocytes' (NEs) characteristics to serve as a long-term sensing platform. Here, we investigate two loading techniques and the properties of the resulting erythrosensors. For loading, hypotonic dilution requires a hypotonic solution while electroporation relies on electrical pulses to perforate the erythrocyte membrane. We analyze the resulting erythrosensor signal, size, morphology, and hemoglobin content. Although the resulting erythrosensors exhibit morphological changes, their size was comparable with NEs. The hypotonic dilution technique was found to load erythrosensors much more efficiently than electroporation, and the sensors were loaded throughout the volume of the erythrosensors. Finally, both techniques resulted in significant loss of hemoglobin. This study points to the need for continued development of loading techniques that better preserve NE characteristics.

  13. Irregular Distortion of The Erythrocytes (Acanthocytes, Spur Cells in Senile Dementia

    Directory of Open Access Journals (Sweden)

    H. B. Goodall

    1994-01-01

    Full Text Available An excess of irregularly di storted red cells with spiked forms (acanthocytes. spur cells has been found in a substantial minority of patient s with seni le dementia of Alzheimer type (7 of 50 patients, 3 of 21 men and 4 of 29 women. Of 100 control patients, 42 men and 58 women, 5 (men and 2 women showed comparable distortion, but, of these, one man may well have incipient dementia and the others had serious organic di seases which may be associated with comparable erythrocytic changes. The cause of the distortion is not yet clear, but the presence of occasional giant erythrocytes in the absence of general macrocytosis suggests a possible abnormality of cell membrane synthes is. This distortion may be a useful marker in patients with loss of memory. Whether it is a manifestation of a haemopoietic clone or a constitutional anomaly associated with Alzheimer’s disease remains to be seen.

  14. Altitude Acclimatization and Blood Volume: Effects of Exogenous Erythrocyte Volume Expansion

    National Research Council Canada - National Science Library

    Sawka, M

    1996-01-01

    ...: (a) altitude acclimatization effects on erythrocyte volume and plasma volume; (b) if exogenous erythrocyte volume expansion alters subsequent erythrocyte volume and plasma volume adaptations; (c...

  15. Swiss-cheese D3- D7 soft SUSY breaking

    Science.gov (United States)

    Misra, Aalok; Shukla, Pramod

    2010-03-01

    We address issues related to (i) a proposal for resolving a long-standing tension between large volume cosmology and phenomenology as regards reconciliation of requirements of different gravitino masses within the same string-theoretic framework, as well as (ii) evaluation of soft supersymmetry breaking terms and open-string moduli masses in the context of type IIB large volume compactifications involving orientifolds of the Swiss-cheese Calabi-Yau WCP[1,1,1,6,9] with a single mobile space-time filling D3-brane and stacks of D7-branes wrapping the "big" divisor Σ as well as supporting D7-brane fluxes. In addition, we also include perturbative α-corrections and non-perturbative world-sheet instanton corrections to the Kähler potential as well as Euclidean D3-instanton superpotential. First, using the toric data for the aforementioned Swiss-cheese Calabi-Yau and GLSM techniques, we obtain in the large volume limit, the geometric Kähler potential for the big (and small) divisor(s) in terms of derivatives of genus-two Siegel theta functions. Next, we show that as the mobile space-time filling D3-brane moves from a particular non-singular elliptic curve embedded in the Swiss-cheese Calabi-Yau to another non-singular elliptic curve, it is possible to obtain 10 12 GeV gravitino during the primordial inflationary era as well as, e.g., a TeV gravitino in the present era, within the same set up for the same volume of the Calabi-Yau stabilized at around 10ls6. Then by constructing local (i.e. localized around the location of the mobile D3-brane in the Calabi-Yau) appropriate involutively-odd harmonic one-form on the big divisor that lies in coker(H∂¯,-(0,1)(CY)→iH∂¯,-(0,1)(Σ)) and extremizing the potential, we show that it is possible to obtain an O(1)g from the wrapping of D7-branes on the big divisor due to competing contributions from the Wilson line moduli relative to the divisor volume modulus. To permit gaugino condensation, we take the rigid limit of the big divisor by considering zero sections of the normal bundle of the same - the same being justified by the extremization of the potential. For the purposes of calculation of the gaugino masses, matter moduli masses and soft supersymmetry breaking parameters, we restrict the mobile D3-brane to the big divisor - this has the additional advantage of nullification of the superpotential generated from gaugino condensation. With the inclusion of the matter moduli corresponding to the position moduli of the mobile D3-brane and the Wilson line moduli corresponding to the D7-branes, we obtain gaugino masses of the order of gravitino mass and the matter fields' masses to be enhanced relative to the gravitino mass. The anomaly-mediated gaugino masses are found to be suppressed relative to the gravity-mediated gaugino masses by the standard loop factor. New non-zero contributions to the μ-terms, though sub-dominant in the large volume limit, are obtained from section of the (small) divisor bundle encoding information about the ED3-instanton fluctuation determinant, filling D3-brane and the Wilson line moduli. There is a (near) universality in the masses, μˆ-parameters, Yukawa couplings and the μˆB-terms for the D3-brane position moduli - the Higgs doublet in our construction - and a hierarchy in the same set and a universality in the A-terms on inclusion of the D7-brane Wilson line moduli.

  16. PODAAC-AQR50-3D7CS

    Data.gov (United States)

    National Aeronautics and Space Administration — Aquarius Level 3 sea surface density standard mapped image data contains gridded 1 degree spatial resolution derived density averaged over daily, 7 day, monthly, and...

  17. PODAAC-AQR50-3D7AS

    Data.gov (United States)

    National Aeronautics and Space Administration — Aquarius Level 3 sea surface density standard mapped image data contains gridded 1 degree spatial resolution density data averaged over daily, 7 day, monthly, and...

  18. PODAAC-AQR50-3D7DS

    Data.gov (United States)

    National Aeronautics and Space Administration — Aquarius Level 3 sea surface density standard mapped image data contains gridded 1 degree spatial resolution density data averaged over daily, 7 day, monthly, and...

  19. Effects of high dietary fluorine on erythrocytes and erythrocyte immune adherence function in broiler chickens.

    Science.gov (United States)

    Deng, Yubing; Cui, Hengmin; Peng, Xi; Fang, Jing; Zuo, Zhicai; Deng, Junliang; Luo, Qin

    2013-11-01

    Fluoride can exert toxic effects on soft tissues, giving rise to a broad array of symptoms and pathological changes. The aim of this study was to investigate on erythrocytes and erythrocyte immune adherence function in broiler chickens fed with high fluorine (F) diets by measuring the total erythrocyte count (TEC), the contents of hemoglobin (Hb), packed cell volumn (PCV), erythrocyte osmotic fragility (EOF), erythrocyte C3b receptor rosette rate (E-C3bRR), and erythrocyte immune complex rosette rate (E-ICRR). A total of 280 1-day-old healthy avian broiler chickens were randomly allotted into four equal groups of 70 birds each and fed with a corn-soybean basal diet containing 22.6 mg F/kg (control group) or same basal diets supplemented with 400, 800, and 1,200 mg F/kg (high F groups I, II, and III) in the form of sodium fluoride for 42 days. Blood samples were collected for the abovementioned parameters analysis at 14, 28, and 42 days of age during the experiment. The experimental results indicated that TEC, Hb, and PCV were significantly lower (p erythrocyte membrane, the transport capacity of oxygen and carbon dioxide, and erythrocyte immune adherence function in broiler chickens.

  20. Cloning-free CRISPR

    NARCIS (Netherlands)

    Arbab, Mandana; Srinivasan, Sharanya; Hashimoto, Tatsunori; Geijsen, Niels; Sherwood, Richard I

    2015-01-01

    We present self-cloning CRISPR/Cas9 (scCRISPR), a technology that allows for CRISPR/Cas9-mediated genomic mutation and site-specific knockin transgene creation within several hours by circumventing the need to clone a site-specific single-guide RNA (sgRNA) or knockin homology construct for each

  1. Cloning, killing, and identity.

    Science.gov (United States)

    McMahan, J

    1999-01-01

    One potentially valuable use of cloning is to provide a source of tissues or organs for transplantation. The most important objection to this use of cloning is that a human clone would be the sort of entity that it would be seriously wrong to kill. I argue that entities of the sort that you and I essentially are do not begin to exist until around the seventh month of fetal gestation. Therefore to kill a clone prior to that would not be to kill someone like you or me but would be only to prevent one of us from existing. And even after one of us begins to exist, the objections to killing it remain comparatively weak until its psychological capacities reach a certain level of maturation. These claims support the permissibility of killing a clone during the early stages of its development in order to use its organs for transplantation. PMID:10226909

  2. Edelfosine Induced Suicidal Death of Human Erythrocytes

    Directory of Open Access Journals (Sweden)

    Marilena Briglia

    2015-11-01

    Full Text Available Background/Aims: The anti-inflammatory, anti-autoimmune, antiparasitic, and anti-viral ether phospholipid edelfosine (1-O-octadecyl-2-O-methylglycero-3-phosphocholine stimulates apoptosis of tumor cells and is thus considered for the treatment of malignancy. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phospholipid scrambling of the cell membrane with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i and oxidative stress. The present study explored, whether and how edelfosine induces eryptosis. Methods: Flow cytometry and photometry, respectively, were employed to estimate phosphatidylserine exposure at the cell surface from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and abundance of reactive oxygen species (ROS from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA fluorescence. Results: A 6 hours exposure of human erythrocytes to edelfosine (5 µM significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter, and significantly increased Fluo3-fluorescence, but did not significantly modify DCFDA fluorescence. The effect of edelfosine on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusions: Edelfosine triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of Ca2+ entry.

  3. Patulin-Induced Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Adrian Lupescu

    2013-07-01

    Full Text Available Background: Patulin, the most common mycotoxin in apples and apple-derived products, triggers apoptosis and has thus been considered for the treatment of cancer. Similar to apoptosis of nucleated cells, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by cell membrane scrambling leading to phosphatidylserine-exposure at the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i. The present study explored, whether exposure of human erythrocytes to patulin is followed by eryptosis. Methods: Forward scatter was measured to estimate cell volume, annexin V binding to detect phosphatidylserine-exposure, hemoglobin release to quantify hemolysis, and Fluo3-fuorescence to determine [Ca2+]i. Results: A 48 h exposure to patulin significantly increased [Ca2+]I (5 µM, significantly decreased forward scatter (5 µM and significantly increased annexin-V-binding (2.5 µM. Patulin (10 µM induced annexin-V-binding was virtually abrogated by removal of extracellular Ca2+. Conclusion: Patulin stimulates Ca2+ entry into erythrocytes, an effect triggering suicidal erythrocyte death or eryptosis.

  4. Patulin-induced suicidal erythrocyte death.

    Science.gov (United States)

    Lupescu, Adrian; Jilani, Kashif; Zbidah, Mohanad; Lang, Florian

    2013-01-01

    Patulin, the most common mycotoxin in apples and apple-derived products, triggers apoptosis and has thus been considered for the treatment of cancer. Similar to apoptosis of nucleated cells, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by cell membrane scrambling leading to phosphatidylserine-exposure at the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca(2+)-activity ([Ca(2+)]i). The present study explored, whether exposure of human erythrocytes to patulin is followed by eryptosis. Forward scatter was measured to estimate cell volume, annexin V binding to detect phosphatidylserine-exposure, hemoglobin release to quantify hemolysis, and Fluo3-fuorescence to determine [Ca(2+)]i. A 48 h exposure to patulin significantly increased [Ca(2+)]I (5 µM), significantly decreased forward scatter (5 µM) and significantly increased annexin-V-binding (2.5 µM). Patulin (10 µM) induced annexin-V-binding was virtually abrogated by removal of extracellular Ca(2+). Patulin stimulates Ca(2+) entry into erythrocytes, an effect triggering suicidal erythrocyte death or eryptosis. Copyright © 2013 S. Karger AG, Basel.

  5. Mapping of hemoglobin in erythrocytes and erythrocyte ghosts using two photon excitation fluorescence microscopy

    Science.gov (United States)

    Bukara, Katarina; Jovanić, Svetlana; Drvenica, Ivana T.; Stančić, Ana; Ilić, Vesna; Rabasović, Mihailo D.; Pantelić, Dejan; Jelenković, Branislav; Bugarski, Branko; Krmpot, Aleksandar J.

    2017-02-01

    The present study describes utilization of two photon excitation fluorescence (2PE) microscopy for visualization of the hemoglobin in human and porcine erythrocytes and their empty membranes (i.e., ghosts). High-quality, label- and fixation-free visualization of hemoglobin was achieved at excitation wavelength 730 nm by detecting visible autofluorescence. Localization in the suspension and spatial distribution (i.e., mapping) of residual hemoglobin in erythrocyte ghosts has been resolved by 2PE. Prior to the 2PE mapping, the presence of residual hemoglobin in the bulk suspension of erythrocyte ghosts was confirmed by cyanmethemoglobin assay. 2PE analysis revealed that the distribution of hemoglobin in intact erythrocytes follows the cells' shape. Two types of erythrocytes, human and porcine, characterized with discocyte and echinocyte morphology, respectively, showed significant differences in hemoglobin distribution. The 2PE images have revealed that despite an extensive washing out procedure after gradual hypotonic hemolysis, a certain amount of hemoglobin localized on the intracellular side always remains bound to the membrane and cannot be eliminated. The obtained results open the possibility to use 2PE microscopy to examine hemoglobin distribution in erythrocytes and estimate the purity level of erythrocyte ghosts in biotechnological processes.

  6. Erythrocyte Membrane Failure by Electromechanical Stress

    Directory of Open Access Journals (Sweden)

    E Du

    2018-01-01

    Full Text Available We envision that electrodeformation of biological cells through dielectrophoresis as a new technique to elucidate the mechanistic details underlying membrane failure by electrical and mechanical stresses. Here we demonstrate the full control of cellular uniaxial deformation and tensile recovery in biological cells via amplitude-modified electric field at radio frequency by an interdigitated electrode array in microfluidics. Transient creep and cyclic experiments were performed on individually tracked human erythrocytes. Observations of the viscoelastic-to-viscoplastic deformation behavior and the localized plastic deformations in erythrocyte membranes suggest that electromechanical stress results in irreversible membrane failure. Examples of membrane failure can be separated into different groups according to the loading scenarios: mechanical stiffening, physical damage, morphological transformation from discocyte to echinocyte, and whole cell lysis. These results show that this technique can be potentially utilized to explore membrane failure in erythrocytes affected by other pathophysiological processes.

  7. Cloning of Plasmodium falciparum by single-cell sorting

    Science.gov (United States)

    Miao, Jun; Li, Xiaolian; Cui, Liwang

    2010-01-01

    Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples. PMID:20435038

  8. Saquinavir Induced Suicidal Death of Human Erythrocytes

    Directory of Open Access Journals (Sweden)

    Sabrina Waibel

    2015-11-01

    Full Text Available Background/Aims: The antiretroviral protease inhibitor saquinavir is used for the treatment of HIV infections. Effects of saquinavir include induction of apoptosis, the suicidal death of nucleated cells. Saquinavir treatment may further lead to anemia. In theory, anemia could result from accelerated erythrocyte loss by enhanced suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i, oxidative stress with increase of reactive oxygen species (ROS and ceramide. The present study explored, whether and how saquinavir induces eryptosis. Methods: To this end, flow cytometry was employed to estimate erythrocyte volume from forward scatter, phosphatidylserine exposure at the cell surface from annexin-V-binding, [Ca2+]i from Fluo3-fluorescence, ROS abundance from DCFDA fluorescence and ceramide abundance utilizing specific antibodies. Results: A 48 hours exposure of human erythrocytes to saquinavir significantly decreased forward scatter (≥ 5 µg/ml, significantly increased the percentage of annexin-V-binding cells (≥ 10 µg/ml, significantly increased Fluo3-fluorescence (15 µg/ml, significantly increased DCFDA fluorescence (15 µg/ml, but did not significantly modify ceramide abundance. The effect of saquinavir on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusions: Saquinavir triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of ROS formation and Ca2+ entry.

  9. Cryo scanning electron microscopy of Plasmodium falciparum-infected erythrocytes

    DEFF Research Database (Denmark)

    Hempel, Casper

    2017-01-01

    Plasmodium falciparum invades erythrocytes as an essential part of their life cycle. While living inside erythrocytes, the parasite remodels the cell's intracellular organization as well as its outer surface. Late trophozoite-stage parasites and schizonts introduce numerous small protrusions...

  10. Lysis of erythrocytes by Trichomonas gallinae.

    Science.gov (United States)

    De Carli, G A; da Silva, A C; Wendorff, A; Rott, M

    1996-01-01

    The hemolytic activity of five live isolates of Trichomonas gallinae was investigated. The isolates were subsequently tested against the erythrocytes of seven adult animal species. Each of the five isolates tested lysed all human blood groups, as well as rabbit, rat, chicken, horse, bovine, and sheep erythrocytes. No hemolysin released by the parasite could be detected. Our preliminary results suggest that the hemolytic activity is not due to the hemolysin release by T. gallinae or to a product of its metabolism. Pretreatment of live trichomonads with concanavalin A reduced levels of hemolysis by 40%.

  11. BIOETHICS AND HUMAN CLONING

    Directory of Open Access Journals (Sweden)

    Željko Kaluđerović

    2011-12-01

    Full Text Available In this paper the authors analyze the process of negotiating and beginning of the United Nations Declaration on Human Cloning as well as the paragraphs of the very Declaration. The negotiation was originally conceived as a clear bioethical debate that should have led to a general agreement to ban human cloning. However, more often it had been discussed about human rights, cultural, civil and religious differences between people and about priorities in case of eventual conflicts between different value systems. In the end, a non-binding Declaration on Human Cloning had been adopted, full of numerous compromises and ambiguous formulations, that relativized the original intention of proposer states. According to authors, it would have been better if bioethical discussion and eventual regulations on cloning mentioned in the following text had been left over to certain professional bodies, and only after the public had been fully informed about it should relevant supranational organizations have taken that into consideration.

  12. Main: Clone Detail [KOME

    Lifescience Database Archive (English)

    Full Text Available Clone Detail Mapping Pseudomolecule data detail Detail information Mapping to the T...IGR japonica Pseudomolecules kome_mapping_pseudomolecule_data_detail.zip kome_mapping_pseudomolecule_data_detail ...

  13. Unified Approach to Universal Cloning and Phase-Covariant Cloning

    OpenAIRE

    Hu, Jia-Zhong; Yu, Zong-Wen; Wang, Xiang-Bin

    2008-01-01

    We analyze the problem of approximate quantum cloning when the quantum state is between two latitudes on the Bloch's sphere. We present an analytical formula for the optimized 1-to-2 cloning. The formula unifies the universal quantum cloning (UQCM) and the phase covariant quantum cloning.

  14. Enzyme free cloning for high throughput gene cloning and expression

    NARCIS (Netherlands)

    de Jong, R.N.; Daniëls, M.; Kaptein, R.|info:eu-repo/dai/nl/074334603; Folkers, G.E.|info:eu-repo/dai/nl/162277202

    2006-01-01

    Structural and functional genomics initiatives significantly improved cloning methods over the past few years. Although recombinational cloning is highly efficient, its costs urged us to search for an alternative high throughput (HTP) cloning method. We implemented a modified Enzyme Free Cloning

  15. Ectopic expression of the erythrocyte band 3 anion exchange protein, using a new avian retrovirus vector

    DEFF Research Database (Denmark)

    Fuerstenberg, S; Beug, H; Introna, M

    1990-01-01

    into protein. Using the Escherichia coli beta-galactosidase gene cloned into the vector as a test construct, expression of enzyme activity could be detected in 90 to 95% of transfected target cells and in 80 to 85% of subsequently infected cells. In addition, a cDNA encoding the avian erythrocyte band 3 anion......A retrovirus vector was constructed from the genome of avian erythroblastosis virus ES4. The v-erbA sequences of avian erythroblastosis virus were replaced by those coding for neomycin phosphotransferase, creating a gag-neo fusion protein which provides G418 resistance as a selectable marker. The v......-erbB sequences following the splice acceptor were replaced by a cloning linker allowing insertion of foreign genes. The vector has been tested in conjunction with several helper viruses for the transmission of G418 resistance, titer, stability, transcription, and the transduction and expression of foreign genes...

  16. Erythrocyte sedimentation rate and C-reactive protein.

    Science.gov (United States)

    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.

  17. Increased caspase-3 immunoreactivity of erythrocytes in STZ diabetic rats.

    Science.gov (United States)

    Fırat, Uğur; Kaya, Savaş; Cim, Abdullah; Büyükbayram, Hüseyin; Gökalp, Osman; Dal, Mehmet Sinan; Tamer, Mehmet Numan

    2012-01-01

    Eryptosis is a term to define apoptosis of erythrocytes. Oxidative stress and hyperglycemia, both of which exist in the diabetic intravascular environment, can trigger eryptosis of erythrocytes. In this experimental study, it is presented that the majority of erythrocytes shows caspase-3 immunoreactivity in streptozocin- (STZ)-induced diabetic rats. Besides that, caspase-3 positive erythrocytes are aggregated and attached to vascular endothelium. In conclusion, these results may start a debate that eryptosis could have a role in the diabetic complications.

  18. Accurate determination of selenium and iron in erythrocytes from ...

    African Journals Online (AJOL)

    Accurate determination of selenium and iron in erythrocytes from Nigeria subjects using INAA. JO Ojo, Jan Kucera. Abstract. Levels of two essential elements playing crucial roles in erythrocyte's structure and functions, iron and selenium, have been carefully determined in 36 erythrocyte samples drawn from two healthy ...

  19. Should erythrocyte destruction in vivo be through phagocytosis alone?

    Indian Academy of Sciences (India)

    did not lower their EDA, strongly suggesting the involvement of non-phagocytic mechanisms in erythrocyte destruction. Assessment of erythrocyte lysis by the chromium release assay of cytotoxicity also provided direct evidence of erythrocyte lysis by leukocytes. T cells appear to be indirectly involved in. EDA associated with.

  20. Paired Chicken and Mammalian Erythrocyte Indicator Systems for ...

    African Journals Online (AJOL)

    Three levels of erythrocytes suspensions, 1.5%, 1% and 0.5% respectively from goat and guinea pig, were compared to conventional 0.5% chicken erythrocytes, in an attempt to investigate the suitability for the two sources of mammalian erythrocytes as indicators for Newcastle disease virus haemagglutination (HA) tests.

  1. 21 CFR 864.6700 - Erythrocyte sedimentation rate test.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Erythrocyte sedimentation rate test. 864.6700... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6700 Erythrocyte sedimentation rate test. (a) Identification. An erythrocyte sedimentation rate test is a device that measures...

  2. Insect cells are superior to Escherichia coli in producing malaria proteins inducing IgG targeting PfEMP1 on infected erythrocytes

    Directory of Open Access Journals (Sweden)

    Joergensen Louise

    2010-11-01

    Full Text Available Abstract Background The PFD1235w Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1 antigen is associated with severe malaria in children and can be expressed on the surface of infected erythrocytes (IE adhering to ICAM1. However, the exact three-dimensional structure of this PfEMP1 and its surface-exposed epitopes are unknown. An insect cell and Escherichia coli based system was used to express single and double domains encoded by the pfd1235w var gene. The resulting recombinant proteins have been evaluated for yield and purity and their ability to induce rat antibodies, which react with the native PFD1235w PfEMP1 antigen expressed on 3D7PFD1235w-IE. Their recognition by human anti-malaria antibodies from previously infected Tanzanian donors was also analysed. Methods The recombinant proteins were run on SDS-PAGE and Western blots for quantification and size estimation. Insect cell and E. coli-produced recombinant proteins were coupled to a bead-based Luminex assay to measure the plasma antibody reactivity of 180 samples collected from Tanzanian individuals. The recombinant proteins used for immunization of rats and antisera were also tested by flow cytometry for their ability to surface label 3D7PFD1235w-IE. Results All seven pAcGP67A constructs were successfully expressed as recombinant protein in baculovirus-infected insect cells and subsequently produced to a purity of 60-97% and a yield of 2-15 mg/L. By comparison, only three of seven pET101/D-TOPO constructs expressed in the E. coli system could be produced at all with purity and yield ranging from 3-95% and 6-11 mg/L. All seven insect cell, but only two of the E. coli produced proteins induced antibodies reactive with native PFD1235w expressed on 3D7PFD1235w-IE. The recombinant proteins were recognized in an age- and transmission intensity-dependent manner by antibodies from 180 Tanzanian individuals in a bead-based Luminex assay. Conclusions The baculovirus based insect cell

  3. Arsenic-induced suicidal erythrocyte death

    Energy Technology Data Exchange (ETDEWEB)

    Mahmud, Hasan; Foeller, Michael; Lang, Florian [University of Tuebingen (Germany). Department of Physiology

    2009-02-15

    Environmental exposure to arsenic has been associated with anemia, which could result from suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and phosphatidylserine exposure at the erythrocyte surface. Eryptosis is triggered by increase in cytosolic Ca{sup 2+} concentration, ceramide and energy depletion. The present experiments explored, whether arsenic stimulates eryptosis. According to annexin V-binding, arsenic trioxide (7{mu}M) within 48 h significantly increased phosphatidylserine exposure of human erythrocytes without inducing hemolysis. According to forward scatter, arsenic trioxide (7{mu}M) significantly decreased cell volume. Moreover, Fluo3-fluorescence showed that arsenic (10 {mu}M) significantly increased cytosolic Ca{sup 2+} concentration. According to binding of respective fluorescent antibodies, arsenic trioxide (10{mu}M) significantly increased ceramide formation. Arsenic (10{mu}M) further lowered the intracellular ATP concentration. Removal of extracellular Ca{sup 2+} or inhibition of the Ca{sup 2+}-permeable cation channels with amiloride blunted the effects of arsenic on annexin V-binding and cell shrinkage. In conclusion, arsenic triggers suicidal erythrocyte death by increasing cytosolic Ca{sup 2+} concentration, by stimulating the formation of ceramide and by decreasing ATP availability. (orig.)

  4. Erythrocyte seditnentation rate in elderly blacks

    African Journals Online (AJOL)

    Abstract This study inv~tigated the erythrocyte sedimen- tation rate (ESR) in an elderly population with the objective of establishing reference ranges and the diagnostic value of the ESR. Elderly blacks were randomly selected frOIn conununities in the. Orange Free State. ESR determinations were done according to the ...

  5. Stimulation of suicidal erythrocyte death by sulforaphane.

    Science.gov (United States)

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

    2015-03-01

    Sulforaphane, an isothiocyanate from cruciferous vegetable, counteracts malignancy. The effect is at least in part due to the stimulation of suicidal death or apoptosis of tumour cells. Mechanisms invoked in sulforaphane-induced apoptosis include mitochondrial depolarization and altered gene expression. Despite the lack of mitochondria and nuclei, erythrocytes may, similar to apoptosis of nucleated cells, enter eryptosis, a suicidal cell death characterized by cell shrinkage and phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca(2+)-activity ([Ca(2+)]i). This study explored whether sulforaphane stimulates eryptosis. Cell volume was estimated from forward scatter, phosphatidylserine exposure at the cell surface from annexin V binding and [Ca(2+)]i from Fluo-3 fluorescence. A 48-hr treatment of human erythrocytes with sulforaphane (50-100 μM) significantly decreased forward scatter, significantly increased the percentage of annexin V binding cells and significantly increased [Ca(2+)]i. The effect of sulforaphane (100 μM) on annexin V binding was significantly blunted but not abrogated by the removal of extracellular Ca(2+). Sulforaphane (100 μM) significantly increased ceramide formation. In conclusion, sulforaphane stimulates suicidal erythrocyte death or eryptosis, an effect at least partially, but not exclusively, due to the stimulation of Ca(2+) entry and ceramide formation. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

  6. Baseline Haematology and Erythrocyte Morphological Changes of ...

    African Journals Online (AJOL)

    olayemitoyin

    Department of Veterinary Pathology, University of Ibadan. Nigeria Ibadan, Nigeria. Summary: This study evaluates the haematological parameters and the observed erythrocytes morphological changes in dogs raised in Ibadan, Oyo State in the south western part of Nigeria. Blood samples were collected from sixty-four.

  7. Baseline Haematology and Erythrocyte Morphological Changes of ...

    African Journals Online (AJOL)

    Summary: This study evaluates the haematological parameters and the observed erythrocytes morphological changes in dogs raised in Ibadan, Oyo State in the south western part of Nigeria. Blood samples were collected from sixty-four apparently healthy dogs. The haematological parameters of the blood samples ...

  8. Erythrocyte aging in sickle cell disease.

    NARCIS (Netherlands)

    Bosman, G.J.C.G.M.

    2004-01-01

    Physiological removal of old erythrocytes from the circulation by macrophages is initiated by binding of autologous IgG to senescent cell antigen (SCA). SCA is generated from the anion exchanger band 3. This process is accompanied by a number of alterations in the function and structure of band 3.

  9. Effect of Lipophilic Bismuth Nanoparticles on Erythrocytes

    Directory of Open Access Journals (Sweden)

    Rene Hernandez-Delgadillo

    2015-01-01

    Full Text Available Lipophilic bismuth dimercaptopropanol nanoparticles (BisBAL NPs have a very important antimicrobial activity; however their effect on human cells or tissues has not been completely studied. Undesirable effects of bismuth include anemia which could result from suicidal erythrocyte death or eryptosis. The objective of this research was to determine the effect of bismuth dimercaptopropanol nanoparticles on blood cells. The nanoparticles are composed of 53 nm crystallites on average and have a spherical structure, agglomerating into clusters of small nanoparticles. Based on cell viability assays and optical microscopy, cytotoxicity on erythrocytes was observed after growing with 500 and 1000 µM of BisBAL NPs for 24 h. AM Calcein was retained inside erythrocytes when they were exposed to 100 µM (or lower concentrations of BisBAL NPs for 24 h, suggesting the absence of damage in plasmatic membrane. Genotoxic assays revealed no damage to genomic DNA of blood cells after 24 h of exposition to BisBAL NPs. Finally, 100–1000 µM of bismuth nanoparticles promotes apoptosis between blood cells after 24 h of incubation. Hence BisBAL NPs at concentrations lower than 100 µM do not cause damage on blood cells; they could potentially be used by humans without affecting erythrocytes and leukocytes.

  10. Brucella melitensis Invades Murine Erythrocytes during Infection

    Science.gov (United States)

    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

  11. The Current Relevance and Applications of Erythrocyte ...

    African Journals Online (AJOL)

    The erythrocyte sedimentation rate (ESR) is a simple and inexpensive laboratory test. It is commonly used to assess the acute phase response. A review of relevant literature was done to evaluate the role of the ESR and its importance in different clinical conditions both inflammatory and non-inflammatory. Despite the critical ...

  12. Changes in Hematological Parameters and Erythrocyte Osmotic ...

    African Journals Online (AJOL)

    The study was aimed at evaluating the changes in haematological parameters and erythrocyte osmotic fragility in lame and aged horses administered with resveratrol supplement (Equithrive joint®). A total of 16 horses of both sexes, aged 18 ± 0.65 and showing lameness grade 3 were used for the study. The horses ...

  13. Electrophoretic mobilities of erythrocytes in various buffers

    Science.gov (United States)

    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.

  14. Changes in haematology, plasma biochemistry and erythrocyte ...

    African Journals Online (AJOL)

    There was also a stress induced increased heterophil/lymphocyte ratio and the erythrocytes were more fragile in hypotonic solution in birds sampled at 8 weeks. Plasma aspartate transaminase (AST), alanine aminotransferase (ALT) and alkaline phosphate (ALP) increased at 8 weeks, though non-significantly, which might ...

  15. Changes in haematology, plasma biochemistry and erythrocyte ...

    African Journals Online (AJOL)

    olayemitoyin

    Summary: The haematology, plasma biochemistry and erythrocyte osmotic fragility of the Nigerian laughing dove. (Streptopelia senegalensis) were studied after 4 and 8 weeks in captivity. At 8 weeks, there was a normocytic hypochromic anaemia characterized by reduced values for packed cell volume (PCV), red blood cell ...

  16. Erythrocyte survival in sheep exposed to ozone

    Energy Technology Data Exchange (ETDEWEB)

    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)

  17. Telfairia Occidentalis Extract Stabilizes Human Erythrocyte ...

    African Journals Online (AJOL)

    In addition to being a widely consumed vegetable in West Africa, the leaves extract of Telfairia occidentalis is believed to have beneficial health effects and is used in tradomedical preparations. The effect of saline extract of T. occidentalis leaves on sickle and normal erythrocytes membrane stability was investigated. Human ...

  18. The correlation between erythrocyte sedimentation rate and ...

    African Journals Online (AJOL)

    Objective: To evaluate the relative importance of infections as indexed by raised erythrocyte sedimentation rate in the aetiology of benign or so called ethnic leucopaenia in persons of African origin. Method: Raised ESR is indicative of the process of organic disease. We sought the correlation of ESR with the total and ...

  19. Erythrocyte stability, membrane protective and haematological ...

    African Journals Online (AJOL)

    The high prevalence rate of diabetes mellitus (DM) in the developing world and its attendant high cost on healthcare have necessitated search for cheaper, effective and readily available alternative therapies in plants. One of such plants used in Nigeria is Newbouldia laevis (P. Beauv) (NLE). Its effect on erythrocyte fragility, ...

  20. Erythrocyte potassium and glutathione polymorphism determination ...

    African Journals Online (AJOL)

    This research is aimed at determining the erythrocyte potassium and glutathione polymorphisms and also to identify the relationship among the various blood parameters in Saanen x Malta crossbred goat raised in Turkey. The allele gene frequencies of KH and KL associated with the potassium concentration were ...

  1. Uric acid increases erythrocyte aggregation: Implications for cardiovascular disease.

    Science.gov (United States)

    Sloop, Gregory D; Bialczak, Jessica K; Weidman, Joseph J; St Cyr, J A

    2016-10-05

    Uric acid may be a risk factor for atherosclerotic cardiovascular disease, although the data conflict and the mechanism by which it may cause cardiovascular disease is uncertain. This study was performed to test the hypothesis that uric acid, an anion at physiologic pH, can cause erythrocyte aggregation, which itself is associated with cardiovascular disease. Normal erythrocytes and erythrocytes with a positive direct antiglobulin test for surface IgG were incubated for 15 minutes in 14.8 mg/dL uric acid. Erythrocytes without added uric acid were used as controls. Erythrocytes were then examined microscopically for aggregation. Aggregates of up to 30 erythrocytes were noted when normal erythrocytes were incubated in uric acid. Larger aggregates were noted when erythrocytes with surface IgG were incubated in uric acid. Aggregation was negligible in controls. These data show that uric acid causes erythrocyte aggregation. The most likely mechanism is decreased erythrocyte zeta potential. Erythrocyte aggregates will increase blood viscosity at low shear rates and increase the risk of atherothrombosis. In this manner, hyperuricemia and decreased zeta potential may be risk factors for atherosclerotic cardiovascular disease.

  2. Conjugated Bilirubin Triggers Anemia by Inducing Erythrocyte Death

    Science.gov (United States)

    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

  3. Study of erythrocyte membrane fluctuation using light scattering analysis

    Science.gov (United States)

    Lee, Hoyoon; Lee, Sangyun; Park, YongKeun; Shin, Sehyun

    2016-03-01

    It is commonly known that alteration of erythrocyte deformability lead to serious microcirculatory diseases such as retinopathy, nephropathy, etc. Various methods and technologies have been developed to diagnose such membrane properties of erythrocytes. In this study, we developed an innovative method to measure hemorheological characteristics of the erythrocyte membrane using a light scattering analysis with simplified optic setting and multi-cell analysis as well. Light scattering intensity through multiple erythrocytes and its power density spectrum were obtained. The results of light scattering analyses were compared in healthy control and artificially hardened sample which was treated with glutaraldehyde. These results were further compared with conventional assays to measure deformable property in hemorheology. We found that light scattering information would reflect the disturbance of membrane fluctuation in artificially damaged erythrocytes. Therefore, measuring fluctuation of erythrocyte membrane using light scattering signal could facilitate simple and precise diagnose of pathological state on erythrocyte as well as related complications.

  4. Inverse fusion PCR cloning.

    Directory of Open Access Journals (Sweden)

    Markus Spiliotis

    Full Text Available Inverse fusion PCR cloning (IFPC is an easy, PCR based three-step cloning method that allows the seamless and directional insertion of PCR products into virtually all plasmids, this with a free choice of the insertion site. The PCR-derived inserts contain a vector-complementary 5'-end that allows a fusion with the vector by an overlap extension PCR, and the resulting amplified insert-vector fusions are then circularized by ligation prior transformation. A minimal amount of starting material is needed and experimental steps are reduced. Untreated circular plasmid, or alternatively bacteria containing the plasmid, can be used as templates for the insertion, and clean-up of the insert fragment is not urgently required. The whole cloning procedure can be performed within a minimal hands-on time and results in the generation of hundreds to ten-thousands of positive colonies, with a minimal background.

  5. Optimal asymptotic cloning machines

    Science.gov (United States)

    Chiribella, Giulio; Yang, Yuxiang

    2014-06-01

    We pose the question whether the asymptotic equivalence between quantum cloning and quantum state estimation, valid at the single-clone level, still holds when all clones are examined globally. We conjecture that the answer is affirmative and present a large amount of evidence supporting our conjecture, developing techniques to derive optimal asymptotic cloners and proving their equivalence with estimation in virtually all scenarios considered in the literature. Our analysis covers the case of arbitrary finite sets of states, arbitrary families of coherent states, arbitrary phase- and multiphase-covariant sets of states, and two-qubit maximally entangled states. In all these examples we observe that the optimal asymptotic cloners enjoy a universality property, consisting in the fact that scaling of their fidelity does not depend on the specific details of the input states, but only on the number of free parameters needed to specify them.

  6. Flow cytometric assessment of canine erythrocytes and platelets for dog erythrocyte antigen 1.1.

    Science.gov (United States)

    Lucidi, Cynthia de A; Takahira, Regina K; Gerlach, John A; Davis, John M; Schwartz, Kenneth A; Scott, Michael A

    2011-12-01

    In human medicine, transfusion of ABO-mismatched platelets has been associated with shortened platelet survival and refractoriness to platelet transfusion because of expression of certain blood group antigens on platelets. It remains unknown if canine platelets express dog erythrocyte antigens (DEAs). The aim of this study was to develop a flow cytometric assay for DEA 1.1 and determine whether DEA 1.1 is present on canine platelets. Blood was collected from 172 clinically healthy dogs. Platelets and erythrocytes from each dog were tested for DEA 1.1 by flow cytometry using anti-DEA 1.1 blood-typing sera. Erythrocytes from each dog were also assessed for DEA 1.1 using a standard tube-typing test (T1) and using a second tube method (T2), if the flow cytometric and T1 results differed. Using flow cytometry, DEA 1.1 was detected on erythrocytes of all 110 dogs shown by T1 or T2 testing to be DEA 1.1-positive. Initial results of the T1 test had a diagnostic accuracy of 93% (160 correct/172 tests). The frequency of erythrocyte DEA 1.1 positivity in previously untyped dogs (n = 118) was 56%. DEA 1.1 expression was not detected on platelets from DEA 1.1-positive dogs. Flow cytometry was a reliable method for detection of DEA 1.1 on canine erythrocytes. The absence of DEA 1.1 on platelets from DEA 1.1-positive dogs suggests that their platelets do not express DEA 1.1 and will not induce production of anti-DEA 1.1 antibodies that might lead to platelet refractoriness or reactions to a subsequent transfusion of DEA 1.1-positive erythrocytes. © 2011 American Society for Veterinary Clinical Pathology.

  7. Antibodies from malaria-exposed pregnant women recognize trypsin resistant epitopes on the surface of Plasmodium falciparum-infected erythrocytes selected for adhesion to chondroitin sulphate A

    DEFF Research Database (Denmark)

    Sharling, Lisa; Enevold, Anders; Sowa, Kordai M P

    2004-01-01

    . falciparum clone FCR3 cultures were used to assay surface IgG binding before and after selection of the parasite for adhesion to CSA. The effect of proteolytic digestion of parasite erythrocyte surface antigens on surface IgG binding and adhesion to CSA and hyaluronic acid (HA) was also studied. RESULTS: P...

  8. Surface co-expression of two different PfEMP1 antigens on single Plasmodium falciparum-infected erythrocytes facilitates binding to ICAM1 and PECAM1

    DEFF Research Database (Denmark)

    Joergensen, Louise; Bengtsson, Dominique C; Bengtsson, Anja

    2010-01-01

    The Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens play a major role in cytoadhesion of infected erythrocytes (IE), antigenic variation, and immunity to malaria. The current consensus on control of variant surface antigen expression is that only one PfEMP1 encoded by one var...... gene is expressed per cell at a time. We measured var mRNA transcript levels by real-time Q-PCR, analysed var gene transcripts by single-cell FISH and directly compared these with PfEMP1 antigen surface expression and cytoadhesion in three different antibody-selected P. falciparum 3D7 sub-lines using......-line was found to bind both CD31/PECAM1 and CD54/ICAM1 and to adhere twice as efficiently to human endothelial cells, compared to infected cells having only one PfEMP1 variant on the surface. These new results on PfEMP1 antigen expression indicate that a re-evaluation of the molecular mechanisms involved in P...

  9. The Cloning of America.

    Science.gov (United States)

    Dobson, Judith E.; Dobson, Russell L.

    1981-01-01

    Proposes that the U.S. school system purports to prize human variability, but many educators are engaged in activities that seek to homogenize students. Describes these activities, including diagnosis, labeling, ability grouping, and positive reinforcement. Presents suggestions for counselors to combat sources of cloning and self-validation. (RC)

  10. Applications of quantum cloning

    Science.gov (United States)

    Pomarico, E.; Sanguinetti, B.; Sekatski, P.; Zbinden, H.; Gisin, N.

    2011-10-01

    Quantum Cloning Machines (QCMs) allow for the copying of information, within the limits imposed by quantum mechanics. These devices are particularly interesting in the high-gain regime, i.e., when one input qubit generates a state of many output qubits. In this regime, they allow for the study of certain aspects of the quantum to classical transition. The understanding of these aspects is the root of the two recent applications that we will review in this paper: the first one is the Quantum Cloning Radiometer, a device which is able to produce an absolute measure of spectral radiance. This device exploits the fact that in the quantum regime information can be copied with only finite fidelity, whereas when a state becomes macroscopic, this fidelity gradually increases to 1. Measuring the fidelity of the cloning operation then allows to precisely determine the absolute spectral radiance of the input optical source. We will then discuss whether a Quantum Cloning Machine could be used to produce a state visible by the naked human eye, and the possibility of a Bell Experiment with humans playing the role of detectors.

  11. Self-Cloning CRISPR

    NARCIS (Netherlands)

    Arbab, M.; Sherwood, R. I.

    2016-01-01

    CRISPR/Cas9-gene editing has emerged as a revolutionary technology to easily modify specific genomic loci by designing complementary sgRNA sequences and introducing these into cells along with Cas9. Self-cloning CRISPR/Cas9 (scCRISPR) uses a self-cleaving palindromic sgRNA plasmid (sgPal) that

  12. Secure the Clones

    Science.gov (United States)

    Jensen, Thomas; Kirchner, Florent; Pichardie, David

    Exchanging mutable data objects with untrusted code is a delicate matter because of the risk of creating a data space that is accessible by an attacker. Consequently, secure programming guidelines for Java stress the importance of using defensive copying before accepting or handing out references to an internal mutable object. However, implementation of a copy method (like clone()) is entirely left to the programmer. It may not provide a sufficiently deep copy of an object and is subject to overriding by a malicious sub-class. Currently no language-based mechanism supports secure object cloning. This paper proposes a type-based annotation system for defining modular copy policies for class-based object-oriented programs. A copy policy specifies the maximally allowed sharing between an object and its clone. We present a static enforcement mechanism that will guarantee that all classes fulfill their copy policy, even in the presence of overriding of copy methods, and establish the semantic correctness of the overall approach in Coq. The mechanism has been implemented and experimentally evaluated on clone methods from several Java libraries.

  13. A Seminar on Human Cloning: Cloning in Reproductive Medicine

    OpenAIRE

    Illmensee, Karl

    2001-01-01

    This review article summarizes the historical development of mammalian cloning, presents current advances and presumed risk factors in the field of reproductive cloning, discusses possible clinical applications of therapeutic and diagnostic cloning and outlines prospective commercial trends in pharmacytical cloning. Predictable progress in biotechnology and stem cell engineering should prove to be advantageous for patients' health and for novel benefits in reproductive and regenerative medicine.

  14. Inhibition of Suicidal Erythrocyte Death by Reversine

    Directory of Open Access Journals (Sweden)

    Mohamed Jemaà

    2017-04-01

    Full Text Available Background/Aims: The A3 adenosine receptor antagonist reversine (2-(4-morpholinoanilino-6-cyclohexylaminopurine influences cellular differentiation, inhibits cell proliferation, induces cell-cycle arrest, triggers apoptosis, causes cell swelling with polyploidy and stimulates autophagy. The effect on apoptosis involves mitochondria and caspases. Erythrocytes are lacking mitochondria but express caspases and are, similar to apoptosis of nucleated cells, able to enter suicidal erythrocyte death or eryptosis. Stimulators of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i, energy depletion and oxidative stress. The present study explored, whether reversine influences eryptosis. Methods: Flow cytometry was employed to quantify phosphatidylserine exposure at the cell surface from annexin-V-binding and cell volume from forward scatter. Measurements were made without or with energy depletion (glucose deprivation for 48 hours, Ca2+ loading (30 minutes treatment with 1 µM Ca2+ ionophore ionomycin, or oxidative stress (15 min exposure to 0.3 mM tert-butylhydroperoxide. Results: A 48 hours exposure of human erythrocytes to reversine (1-10 µM did not significantly modify the percentage of annexin-V-binding cells and forward scatter. Energy depletion, Ca2+ loading, and oxidative stress were each followed by profound and significant increase of the percentage annexin-V-binding erythrocytes and a significant decrease of forward scatter. The effects of each, Ca2+ loading, energy depletion and oxidative stress on annexin-V-binding were significantly blunted in the presence of reversine (1-10 µM. The effect of ionomycin, but not the effects of energy depletion and oxidative stress on forward scatter were again significantly blunted in the presence of reversine (≥1 µM]. Conclusions: Reversine is a powerful inhibitor of cell membrane scrambling following energy depletion, Ca2+ loading and oxidative stress.

  15. Lapatinib Induced Suicidal Death of Human Erythrocytes

    Directory of Open Access Journals (Sweden)

    Jens Zierle

    2015-12-01

    Full Text Available Background/Aims: The human epidermal growth factor receptors tyrosine kinase inhibitor lapatinib has been shown to trigger suicidal death or apoptosis of tumor cells and is thus used for the treatment of malignancy. Side effects of lapatinib include anemia, which could, at least in theory, result from stimulation of eryptosis, the suicidal death of erythrocytes which is characterized by cell shrinkage and phospholipid scrambling of the cell membrane leading to phosphatidylserine translocation to the erythrocyte surface. Mechanisms involved in the triggering of eryptosis include oxidative stress, increase of cytosolic Ca2+ activity ([Ca2+]i, and ceramide. The present study explored, whether lapatinib induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, abundance of reactive oxygen species (ROS from DCFDA dependent fluorescence, and ceramide abundance utilizing labelled specific antibodies. Results: A 48 hours exposure of human erythrocytes to lapatinib (≥ 1 µg/ml significantly increased the percentage of annexin-V-binding cells, and significantly decreased forward scatter. Lapatinib (7.5 µg/ml did not significantly modify DCFDA fluorescence and ceramide abundance. Lapatinib slightly, but significantly decreased Fluo3-fluorescence (≥ 5 µg/ml. Lapatinib (7.5 µg/ml enhanced the annexin-V-binding in the presence of the Ca2+ ionophore ionomycin (1 µM without significantly modifying Fluo3 fluorescence in the presence of ionomycin. The effect of lapatinib on forward scatter but not on annexin-V-binding was significantly blunted by removal of extracellular Ca2+. Conclusion: Lapatinib triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect occurring despite decrease of cytosolic Ca2+ activity.

  16. Stabilization of Erythrocyte Membranes by Polyamines

    Science.gov (United States)

    Ballas, Samir K.; Mohandas, Narla; Marton, Laurence J.; Shohet, Stephen B.

    1983-04-01

    Using a laser diffraction technique, we have studied the effects of putrescine, spermidine, and spermine, the three physiologic polyamines, on the deformability and mechanical stability of human erythrocyte membranes. Ghosts resealed with polyamines were subjected to high fluid shear stress in an ektacytometer. All polyamines increased the membrane shear modulus (decreased deformability) in a concentration- and time-dependent manner. The order of effectiveness was spermine > spermidine > putrescine. At 10 μ M, spermine appreciably decreased membrane deformability. For the measurement of membrane mechanical stability, resealed ghosts were subjected to constant high shear stress in the ektacytometer and deformability was continuously recorded as the deformable ghosts fragmented into rigid spherical vesicles. Polyamines, especially spermine, caused a noticeable increase in the t1/2 for fragmentation. These effects could not be ascribed to proteolysis or Ca2+-induced transglutamination. That the effects of polyamines were specific and not simply due to their positive charge was demonstrated by the finding that Ca2+ and Mg2+ destabilized the erythrocyte membrane as evidenced by decreasing the t1/2 for fragmentation. Extracellular polyamines were not effective except under conditions that caused significant accumulation inside the cell. The data indicate that intracellular physiologic polyamines, especially spermine, decrease erythrocyte membrane deformability and stabilize the membrane skeleton, making it more resistant to fragmentation.

  17. Induction of Suicidal Erythrocyte Death by Novobiocin

    Directory of Open Access Journals (Sweden)

    Adrian Lupescu

    2014-03-01

    Full Text Available Background: Novobiocin, an aminocoumarin antibiotic, interferes with heat shock protein 90 and hypoxia inducible factor dependent gene expression and thus compromises cell survival. Similar to survival of nucleated cells, erythrocyte survival could be disrupted by eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and by phospholipd scrambling of the cell membrane with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i. The Ca2+ sensitivity of phospholipid scrambling is enhanced by ceramide. The present study explored, whether novobiocin elicits eryptosis. Methods: [Ca2+]i was estimated from Fluo3-fluorescence, ceramide abundance utilizing fluorescent antibodies, cell volume from forward scatter, phosphatidylserine-exposure from annexin V binding. Results: A 48 hours exposure to novobiocin (500 µM was followed by a significant increase of [Ca2+]i, decrease of forward scatter, increase of annexin-V-binding and enhanced ceramide formation. Removal of extracellular Ca2+ virtually abrogated the increase of annexin-V-binding following novobiocin exposure. Conclusions: Novobiocin stimulates eryptosis, an effect at least in part due to entry of extracellular Ca2+ and formation of ceramide.

  18. The First Human Cloned Embryo.

    Science.gov (United States)

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  19. [Nuclear transfer and therapeutic cloning].

    Science.gov (United States)

    Xu, Xiao-Ming; Lei, An-Min; Hua, Jin-Lian; Dou, Zhong-Ying

    2005-03-01

    Nuclear transfer and therapeutic cloning have widespread and attractive prospects in animal agriculture and biomedical applications. We reviewed that the quality of oocytes and nuclear reprogramming of somatic donor cells were the main reasons of the common abnormalities in cloned animals and the low efficiency of cloning and showed the problems and outlets in therapeutic cloning, such as some basic problems in nuclear transfer affected clinical applications of therapeutic cloning. Study on isolation and culture of nuclear transfer embryonic stem (ntES) cells and specific differentiation of ntES cells into important functional cells should be emphasized and could enhance the efficiency. Adult stem cells could help to cure some great diseases, but could not replace therapeutic cloning. Ethics also impeded the development of therapeutic cloning. It is necessary to improve many techniques and reinforce the research of some basic theories, then somatic nuclear transfer and therapeutic cloning may apply to agriculture reproduction and benefit to human life better.

  20. Animal Cloning and Food Safety

    Science.gov (United States)

    ... Home For Consumers Consumer Updates Animal Cloning and Food Safety Share Tweet Linkedin Pin it More sharing options ... on clones of livestock animals to evaluate the safety of food from these animals. The resulting report, called a ...

  1. HUMAN CLONING AND FDA REGULATION

    OpenAIRE

    Vosk, Ted

    1998-01-01

    In the February 27, 1997 issue of the journal Nature scientists from Scotland's Roslin Institute reported their successful efforts to clone an adult sheep using differentiated somatic cells from the animal. The clone, named Dolly, was the first instance of the successful cloning of an adult mammal. The shock waves created by the possible ramifications of this development were immediately felt around the world. For the first time, the cloning of an adult human being was no longer being conside...

  2. Metabolomic analysis of normal and sickle cell erythrocytes.

    Science.gov (United States)

    Darghouth, D; Koehl, B; Junot, C; Roméo, P-H

    2010-09-01

    Metabolic signatures of specialized circulating hematopoietic cells in physiological or human hematological diseases start to be described. We use a simple and highly reproductive extraction method of erythrocytes metabolites coupled with a liquid chromatography-mass spectrometry based metabolites profiling method to determine metabolomes of normal and sickle cell erythrocytes. Sickle cell erythrocytes and normal erythrocytes metabolomes display major differences in glycolysis, in glutathione, in ascorbate metabolisms and in metabolites associated to membranes turnover. In addition, the amounts of metabolites derived from urea cycle and NO metabolism that partly take place within erythrocyte were different between normal and sickle cell erythrocytes. These results show that metabolic profiling of red blood cell diseases can now be determined and might indicate new biomarkers that can be used for the follow-up of sickle cell patients. Copyright 2010. Published by Elsevier SAS.

  3. Recombinational Cloning Using Gateway and In-Fusion Cloning Schemes

    Science.gov (United States)

    Throop, Andrea L.; LaBaer, Joshua

    2015-01-01

    The comprehensive study of protein structure and function, or proteomics, depends on the obtainability of full-length cDNAs in species-specific expression vectors and subsequent functional analysis of the expressed protein. Recombinational cloning is a universal cloning technique based on site-specific recombination that is independent of the insert DNA sequence of interest, which differentiates this method from the classical restriction enzyme-based cloning methods. Recombinational cloning enables rapid and efficient parallel transfer of DNA inserts into multiple expression systems. This unit summarizes strategies for generating expression-ready clones using the most popular recombinational cloning technologies, including the commercially available Gateway® (Life Technologies) and In-Fusion® (Clontech) cloning technologies. PMID:25827088

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  5. [Functional state feature of erythrocytes in healthy term newborn infants].

    Science.gov (United States)

    Evsiukova, I I; Iakushenko, N S; Andreeva, A A; Shevel'kova, A A; Kolesova, T A; Katiukhin, L N; Dobrylko, I A; Mandukshev, I V

    2014-01-01

    Hematological parameters and functional status of erythrocytes were studied by the osmotic and ammonium loads in healthy newborns and in adults. Mean erythrocyte volume of newborns more than in adults. Significant difference index of osmotic fragility of neonates were observed in the transition from swelling to hemolysis. Kinetic of erythrocyte's hemolysis in the ammonium load was studied by low-angle light scattering (LaSca-analyzer). The percentage of erythrocyte hemolysis is lower and the velocity of hemolysis is 2.5 times slower in newborns than in adults.

  6. Evolution of erythrocyte morphology in amphibians (Amphibia: Anura

    Directory of Open Access Journals (Sweden)

    Jie Wei

    2015-10-01

    Full Text Available ABSTRACT We compared the morphology of the erythrocytes of five anurans, two toad species - Bufo gargarizans (Cantor, 1842 and Duttaphrynus melanostictus (Schneider, 1799 and three frog species - Fejervarya limnocharis (Gravenhorst, 1829, Microhyla ornata (Duméril & Bibron, 1841, and Rana zhenhaiensis (Ye, Fei & Matsui, 1995. We then reconstructed the ancestral state of erythrocyte size (ES and nuclear size (NS in amphibians based on a molecular tree. Nine morphological traits of erythrocytes were all significantly different among the five species. The results of principal component analysis showed that the first component (49.1% of variance explained had a high positive loading for erythrocyte length, nuclear length, NS and ratio of erythrocyte length/erythrocyte width; the second axis (28.5% of variance explained mainly represented erythrocyte width and ES. Phylogenetic generalized least squares analysis showed that the relationship between NS and ES was not affected by phylogenetic relationships although there was a significant linear relationship between these two variables. These results suggested that (1 the nine morphological traits of erythrocytes in the five anuran species were species-specific; (2 in amphibians, larger erythrocytes generally had larger nuclei.

  7. Variations on Fibrinogen-Erythrocyte Interactions during Cell Aging

    Science.gov (United States)

    Carvalho, Filomena A.; de Oliveira, Sofia; Freitas, Teresa; Gonçalves, Sónia; Santos, Nuno C.

    2011-01-01

    Erythrocyte hyperaggregation, a cardiovascular risk factor, is considered to be caused by an increase in plasma adhesion proteins, particularly fibrinogen. We have recently reported a specific binding between fibrinogen and an erythrocyte integrin receptor with a β3 or β3-like subunit. In this study we evaluate the influence of erythrocyte aging on the fibrinogen binding. By atomic force microscopy-based force spectroscopy measurements we found that increasing erythrocyte age, there is a decrease of the binding to fibrinogen by decreasing the frequency of its occurrence but not its force. This observation is reinforced by zeta-potential and fluorescence spectroscopy measurements. We conclude that upon erythrocyte aging the number of fibrinogen molecules bound to each cell decreases significantly, due to the progressive impairment of the specific fibrinogen-erythrocyte receptor interaction. Knowing that younger erythrocytes bind more to fibrinogen, we could presume that this population is the main contributor to the cardiovascular diseases associated with increased fibrinogen content in blood, which could disturb the blood flow. Our data also show that the sialic acids exposed on the erythrocyte membrane contribute for the interaction with fibrinogen, possibly by facilitating its binding to the erythrocyte membrane receptor. PMID:21464904

  8. Physicochemical Aspects of the Plasmodium chabaudi-Infected Erythrocyte

    Science.gov (United States)

    Hayakawa, Eri H.; Kobayashi, Seiki; Matsuoka, Hiroyuki

    2015-01-01

    Membrane electrochemical potential is a feature of the molecular profile of the cell membrane and the two-dimensional arrangement of its charge-bearing molecules. Plasmodium species, the causative agents of malaria, are intracellular parasites that remodel host erythrocytes by expressing their own proteins on erythrocyte membranes. Although various aspects of the modifications made to the host erythrocyte membrane have been extensively studied in some human Plasmodium species (such as Plasmodium falciparum), details of the structural and molecular biological modifications made to host erythrocytes by nonhuman Plasmodium parasites have not been studied. We employed zeta potential analysis of erythrocytes parasitized by P. chabaudi, a nonhuman Plasmodium parasite. From these measurements, we found that the surface potential shift was more negative for P. chabaudi-infected erythrocytes than for P. falciparum-infected erythrocytes. However, electron microscopic analysis of the surface of P. chabaudi-infected erythrocytes did not reveal any modifications as compared with nonparasitized erythrocytes. These results suggest that differences in the membrane modifications found herein represent unique attributes related to the pathogenesis profiles of the two different malaria parasite species in different host animals and that these features have been acquired through parasite adaptations acquired over long evolutionary time periods. PMID:26557685

  9. Monosaccharide transport in protein-depleted vesicles from erythrocyte membranes

    National Research Council Canada - National Science Library

    M A Zoccoli; G E Lienhard

    1977-01-01

    .... Based on comparisons between erythrocytes and vesicles with regard to specificity, temparture dependence, and effects of inhibitors, we conclude that sorbose uptake into the vesicles occurs by way...

  10. Three concepts of cloning in human beings.

    Science.gov (United States)

    Cui, Ke-Hui

    2005-07-01

    Human cloning, organ cloning and tissue cloning are various types of cloning that occur at different levels with different methodologies. According to three standards of terminology for an embryo (fertilization through germ cells, development in the uterus and having the potential to produce a human life), tissue cloning and type I organ cloning will not produce an embryo. In contrast, human cloning and type II organ cloning will produce an embryo. Thus, only non-germinal tissue cloning and type I organ cloning are beyond the ethical question and will not change human beings as a species. Using cloned tissues to make new tissues or organs is promising for the future of medicine.

  11. Optimally cloned binary coherent states

    Science.gov (United States)

    Müller, C. R.; Leuchs, G.; Marquardt, Ch.; Andersen, U. L.

    2017-10-01

    Binary coherent state alphabets can be represented in a two-dimensional Hilbert space. We capitalize this formal connection between the otherwise distinct domains of qubits and continuous variable states to map binary phase-shift keyed coherent states onto the Bloch sphere and to derive their quantum-optimal clones. We analyze the Wigner function and the cumulants of the clones, and we conclude that optimal cloning of binary coherent states requires a nonlinearity above second order. We propose several practical and near-optimal cloning schemes and compare their cloning fidelity to the optimal cloner.

  12. Cloning-free CRISPR

    Directory of Open Access Journals (Sweden)

    Mandana Arbab

    2015-11-01

    Full Text Available We present self-cloning CRISPR/Cas9 (scCRISPR, a technology that allows for CRISPR/Cas9-mediated genomic mutation and site-specific knockin transgene creation within several hours by circumventing the need to clone a site-specific single-guide RNA (sgRNA or knockin homology construct for each target locus. We introduce a self-cleaving palindromic sgRNA plasmid and a short double-stranded DNA sequence encoding the desired locus-specific sgRNA into target cells, allowing them to produce a locus-specific sgRNA plasmid through homologous recombination. scCRISPR enables efficient generation of gene knockouts (∼88% mutation rate at approximately one-sixth the cost of plasmid-based sgRNA construction with only 2 hr of preparation for each targeted site. Additionally, we demonstrate efficient site-specific knockin of GFP transgenes without any plasmid cloning or genome-integrated selection cassette in mouse and human embryonic stem cells (2%–4% knockin rate through PCR-based addition of short homology arms. scCRISPR substantially lowers the bar on mouse and human transgenesis.

  13. Investigation of High-Speed Erythrocyte Flow and Erythrocyte-Wall Impact in a Lab-on-a-Chip.

    Science.gov (United States)

    Li, Ping; Zheng, Lu; Zhang, Di; Xie, Yonghui; Feng, Yi; Xie, Gongnan

    2016-11-01

    To better understand erythrocyte high-speed motion, collision characteristics, and collision-induced hemolysis probability in rotary blood pumps, a visual experimental investigation of high-speed erythrocyte flow and erythrocyte-wall collision in a lab-on-a-chip was performed. The erythrocyte suspension was driven by a microsyringe pump connected to the microchip, and the erythrocyte flow and erythrocyte-wall impact process were observed and imaged by an optical microscope and a high-speed camera. Two types of microchips with different impact surfaces (flat and curved) were employed. The motion and deformation features before and after collision were studied in detail. The results show that erythrocytes not only move along the flow direction in the flow plane but also rotate and roll in three-dimensional space. Erythrocytes keep discoid shape during the movement in the straight channel, but their deformations during collision are mainly classified into two types: erythrocyte structure is still stable and the erythrocyte performance can be ensured to a certain extent in the TypeA deformation, while the TypeB deformation makes the membrane more likely to fracture on the stretched side, increasing the probability of hemolysis. Furthermore, the movements and deformations of the erythrocytes after collision are analyzed and classified into two types: bouncing and slipping. Moreover, a simulation method for the flow in microchip was performed and validated through a comparison of the streamlines and experimental erythrocytes tracks, which can be further employed to predict the high-speed blood flow, associated with collision process in mechanical blood pump. Copyright © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  14. Phospholipid epitopes for mouse antibodies against bromelain-treated mouse erythrocytes.

    Science.gov (United States)

    Kawaguchi, S

    1987-01-01

    The reactivity of mouse antibodies against bromelain-treated mouse erythrocytes (BrMRBC) with phospholipid epitopes was assessed by ELISA, using four clones of monoclonal anti-BrMRBC antibodies that had idiotypes distinct from one another. The four antibodies could bind to low-density lipoproteins (LDL) from human and chicken, but not to LDL from mouse and rat. As to liposomes of natural phospholipids, all the clones reacted with liposomes of phosphatidylcholine, and some of them could react with liposomes of sphingomyelin, phosphatidylglycerol, phosphatidylic acid or cardiolipin. For liposomes of synthetic phosphatidylcholine with different fatty acids, the length of carbon chains and the number of unsaturated carbon chains of the fatty acids markedly affected the binding of each monoclonal antibody to the liposomes. The addition of dicetyl phosphate or stearylamine to phosphatidylcholine liposomes changed the reactivity of the liposomes. These results support the view that mouse anti-BrMRBC antibodies can recognize appropriately spaced phosphorylcholine residues on the surface of phospholipid liposomes, LDL and cells. The four clones had similar capacities for binding to LDL as well as to BrMRBC, but they had obviously different capacities for binding to phospholipid liposomes; the epitopes on phospholipid liposomes used in the present study were not so perfect as to react well with every anti-BrMRBC antibody. PMID:2443446

  15. Storage-induced changes in erythrocyte membrane proteins promote recognition by autoantibodies.

    NARCIS (Netherlands)

    Dinkla, S.; Novotny, V.M.J.; Joosten, I.; Bosman, G.J.C.G.M.

    2012-01-01

    Physiological erythrocyte removal is associated with a selective increase in expression of neoantigens on erythrocytes and their vesicles, and subsequent autologous antibody binding and phagocytosis. Chronic erythrocyte transfusion often leads to immunization and the formation of alloantibodies and

  16. Ethical issues in animal cloning.

    Science.gov (United States)

    Fiester, Autumn

    2005-01-01

    The issue of human reproductive cloning has recently received a great deal attention in public discourse. Bioethicists, policy makers, and the media have been quick to identify the key ethical issues involved in human reproductive cloning and to argue, almost unanimously, for an international ban on such attempts. Meanwhile, scientists have proceeded with extensive research agendas in the cloning of animals. Despite this research, there has been little public discussion of the ethical issues raised by animal cloning projects. Polling data show that the public is decidedly against the cloning of animals. To understand the public's reaction and fill the void of reasoned debate about the issue, we need to review the possible objections to animal cloning and assess the merits of the anti-animal cloning stance. Some objections to animal cloning (e.g., the impact of cloning on the population of unwanted animals) can be easily addressed, while others (e.g., the health of cloned animals) require more serious attention by the public and policy makers.

  17. Metallic mercury uptake by catalase Part 1 In Vitro metallic mercury uptake by various kind of animals' erythrocytes and purified human erythrocyte catalase

    OpenAIRE

    劒持,堅志

    1980-01-01

    The uptake of metallic mercury was studied using erythrocytes with different catalase activities taken from various kind of animals. The results were: 1) The uptake of metallic mercury by erythrocytes paralleled the activity of catalase in the erythrocytes with and without hydrogen peroxide, suggesting that the erythrocyte catalase activity is related to the uptake of metallic mercury. 2) The uptake of metallic mercury occurred not only with purified human erythrocyte catalase but also with h...

  18. Erythrocyte aging: a more than superficial resemblance to apoptosis?

    NARCIS (Netherlands)

    Bosman, G.J.C.G.M.; Willekens, F.L.A.; Werre, J.M.

    2005-01-01

    In physiological circumstances, erythrocyte aging leads to binding of autologous IgG followed by recognition and removal through phagocytosis, mainly by Kupffer cells in the liver. This process is triggered by the appearance of a senescent erythrocyte-specific antigen. The functional and structural

  19. Long term storage stabilizes human erythrocyte membrane in ...

    African Journals Online (AJOL)

    Osmotic fragility (OF) test was conducted in Nigerian human black male erythrocytes stored for Oh, 12h, 24h and 48h. Storage of these human erythrocytes for up to 24h failed to alter significantly their membrane characteristics. A leftward shift in osmotic fragiligrams was noted suggestive of storage-time (age) dependent ...

  20. The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis

    Directory of Open Access Journals (Sweden)

    Deanna M. Schmitt

    2017-05-01

    Full Text Available Francisella tularensis is an extremely virulent bacterium that can be transmitted naturally by blood sucking arthropods. During mammalian infection, F. tularensis infects numerous types of host cells, including erythrocytes. As erythrocytes do not undergo phagocytosis or endocytosis, it remains unknown how F. tularensis invades these cells. Furthermore, the consequence of inhabiting the intracellular space of red blood cells (RBCs has not been determined. Here, we provide evidence indicating that residing within an erythrocyte enhances the ability of F. tularensis to colonize ticks following a blood meal. Erythrocyte residence protected F. tularensis from a low pH environment similar to that of gut cells of a feeding tick. Mechanistic studies revealed that the F. tularensis type VI secretion system (T6SS was required for erythrocyte invasion as mutation of mglA (a transcriptional regulator of T6SS genes, dotU, or iglC (two genes encoding T6SS machinery severely diminished bacterial entry into RBCs. Invasion was also inhibited upon treatment of erythrocytes with venom from the Blue-bellied black snake (Pseudechis guttatus, which aggregates spectrin in the cytoskeleton, but not inhibitors of actin polymerization and depolymerization. These data suggest that erythrocyte invasion by F. tularensis is dependent on spectrin utilization which is likely mediated by effectors delivered through the T6SS. Our results begin to elucidate the mechanism of a unique biological process facilitated by F. tularensis to invade erythrocytes, allowing for enhanced colonization of ticks.

  1. Arsenate V induced glutathione efflux from human erythrocytes.

    Science.gov (United States)

    Yildiz, Deniz; Cakir, Yeliz

    2012-01-01

    The objective of the present study was to investigate if arsenate V exposure results in glutathione efflux from human erythrocytes. The changes in intracellular and extracellular nonprotein sulfhydryl and glutathione levels were determined in arsenate (V) exposed erythrocytes. Presence of any cellular membrane damage was assessed by lactate dehydrogenase activity measurement in the supernatant. When erythrocytes were exposed to 10 mM of arsenate (V) for 4 h, the intracellular NPSH level decreased to 0.28±0025 μmol/ml erythrocyte. In contrast, extracellular nonprotein thiol level was increased to 0.180±0.010 μmol/ml erythrocyte in 4 h. Extracellular glutathione levels reached to 0.028±0.001, 0.052±0.002, and 0.054±0.004 μmol/ml erythrocyte with 1, 5, and 10 mM of arsenate (V), respectively. Utilization of MK571 a multi drug resistance-associated protein 1 inhibitor decreased the rate of glutathione efflux from erythrocytes suggesting a role for this membrane transporter in the process. The results of the present study indicate that erythrocytes efflux glutathione when exposed to arsenate (V). Copyright © 2011 Elsevier GmbH. All rights reserved.

  2. Murine erythrocytes contain high levels of lysophospholipase activity

    NARCIS (Netherlands)

    Kamp, J.A.F. op den; Roelofsen, B.; Sanderink, G.; Middelkoop, E.; Hamer, R.

    1984-01-01

    Murine erythrocytes were found to be unique in the high levels of lysophospholipase activity in the cytosol of these cells. The specific activity of the enzyme in the cytosol of the murine cells is 10-times higher than in the cytosol of rabbit erythrocytes and approximately three orders of magnitude

  3. Effect of laser irradiation of donor blood on erythrocyte shape.

    Science.gov (United States)

    Baibekov, I M; Ibragimov, A F; Baibekov, A I

    2012-04-01

    Changes in erythrocyte shape in donor blood during storage and after irradiation with He-Ne laser and infrared laser were studied by scanning electron microscopy, thick drop express-method, and morphometry. It was found that laser irradiation delayed the appearance of erythrocytes of pathological shapes (echinocytes, stomatocytes, etc.) in the blood; He-Ne laser produced a more pronounced effect.

  4. Phenotypic drift in osmotic fragility of Sahel goat erythrocytes ...

    African Journals Online (AJOL)

    Abstract. A typical mammalian erythrocyte fragility phenotype (EFP) exhibits a sigmoidal curve of the dependence of fragilities (% haemolysis) on hypotonic saline concentrations, but the goat EFP tends to be hyperbolic. Physiological variation in median erythrocyte fragility (MEF) and the associated EFP of Sahel goats was ...

  5. Activation of human erythrocyte glutathione – s – transferase (EC ...

    African Journals Online (AJOL)

    ) of the isolated caffeine were tested in-vitro on their possible effect on human erythrocyte (red cell) glutathione – S – transferase (EC. 2.5.1.18) activity. The result indicated significant (P < 0.05) activation of the erythrocyte enzyme (GST) by ...

  6. CD47 functions as a molecular switch for erythrocyte phagocytosis

    NARCIS (Netherlands)

    Burger, Patrick; Hilarius-Stokman, Petra; de Korte, Dirk; van den Berg, Timo K.; van Bruggen, Robin

    2012-01-01

    CD47 on erythrocytes inhibits phagocytosis through interaction with the inhibitory immunoreceptor SIRP alpha expressed by macrophages. Thus, the CD47-SIRP alpha interaction constitutes a negative signal for erythrocyte phagocytosis. However, we report here that CD47 does not only function as a "do

  7. [The effect of low intensity luminescent radiation on erythrocyte membranes].

    Science.gov (United States)

    Monich, V A

    1994-01-01

    It was found that luminescent monochromatized incoherent radiation causes inhibition of the ultraviolet light-induced hemolysis of erythrocytes comparable to that induced by laser light. The obtained data show reduction of the molecular product rate of free radical fat acyclic oxidation in the membranes of intact erythrocytes after irradiation by low intensity red light.

  8. The clinical importance of erythrocyte deformability, a hemorrheological parameter

    NARCIS (Netherlands)

    Mokken, F. C.; Kedaria, M.; Henny, C. P.; Hardeman, M. R.; Gelb, A. W.

    1992-01-01

    Hemorheology, the science of the flow behavior of blood, has become increasingly important in clinical situations. The rheology of blood is dependent on its viscosity, which in turn is influenced by plasma viscosity, hematocrit, erythrocyte aggregation, and erythrocyte deformability. In recent years

  9. A role of phosphatidylserine externalization in clearance of erythrocytes exposed to stress but not in eliminating aging populations of erythrocyte in mice.

    Science.gov (United States)

    Khandelwal, Sanjay; Saxena, Rajiv K

    2008-08-01

    Age dependent changes in phosphatidylserine (PS) externalization were studied in mouse erythrocytes of different age groups (range 1-55 days) by using a newly developed double in vivo biotinylation (DIB) technique. Around 3-4% of the erythrocytes freshly released in the circulation were PS(+) but this proportion fell rapidly to 1% or less and did not increase at later time points. Blocking erythrocyte clearance from the circulation by in vivo depletion of macrophages (by treatment with clodronate loaded liposomes) for up to 7 days did not result in accumulation of PS(+) erythrocytes in the circulation indicating that the low percentage of PS(+) cells within old erythrocytes (age >40 days) was not related to the clearance of PS(+) erythrocytes by macrophages. In vitro treatment with stress inducing agents like deoxyglucose or Ca(++)/calcium ionophore resulted in a marked induction of PS externalization in mouse erythrocytes and this effect was most prominent in the youngest erythrocyte population (age erythrocytes after intravenous infusion into recipient mice indicated that the young erythrocytes were cleared at fastest rate from the circulation as compared to erythrocytes of older age groups. Within young erythrocytes exposed to stress, PS(+) erythrocytes were preferentially cleared. Taken together our results suggest that PS externalization is unlikely to have a role in the removal of old erythrocytes from blood circulation but may have a role in the clearance of stressed and damaged young erythrocytes in blood circulation.

  10. Migraine and erythrocyte biology: a review.

    Science.gov (United States)

    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. © 2014 John Wiley & Sons Ltd.

  11. Mitoxantrone-Induced Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Markus Arnold

    2014-11-01

    Full Text Available Background/Aims: Mitoxantrone, a cytotoxic drug used for the treatment of malignancy and multiple sclerosis, is at least in part effective by triggering apoptosis. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, a type of suicidal cell death. Hallmarks of eryptosis are cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signalling involved in eryptosis include Ca2+-entry, ceramide formation and oxidative stress. Methods: Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, formation of reactive oxidant species (ROS from 2′,7′-dichlorodihydrofluorescein-diacetate fluorescence, and ceramide abundance from binding of fluorescent antibodies in flow cytometry. Results: A 48 hours exposure to mitoxantrone was followed by significant decrease of forward scatter (≥ 5 μg/ml mitoxantrone and increase of annexin-V-binding (≥ 10 μg/ml mitoxantrone, effects paralleled by significant increases of ROS formation (25 μg/ml mitoxantrone and ceramide abundance (25 μg/ml mitoxantrone. The effect of mitoxantrone was not significantly modified by nominal absence of extracellular Ca2+ but significantly blunted by the antioxidant N-acetylcysteine (1 mM. Conclusions: Mitoxantrone triggers cell membrane scrambling, an effect not requiring entry of extracellular Ca2+ but at least partially due to formation of ROS and ceramide.

  12. Binding characteristics of swine erythrocyte insulin receptors

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Erythrocyte membrane skeleton inhibits nanoparticle endocytosis

    Science.gov (United States)

    Gao, Xinli; Yue, Tongtao; Tian, Falin; Liu, Zhiping; Zhang, Xianren

    2017-06-01

    Red blood cells (RBCs), also called erythrocytes, have been experimentally proposed in recent decades as the biological drug delivery systems through entrapping certain drugs by endocytosis. However, the internalization pathway of endocytosis seems to conflict with the robust mechanical properties of RBCs that is induced by the spectrin-actin network of erythrocyte membrane skeleton. In this work, we employed a minimum realistic model and the dissipative particle dynamics method to investigate the influence of the spectrin-actin membrane skeleton on the internalization of nanoparticles (NPs). Our simulations show that the existence of skeleton meshwork indeed induces an inhibiting effect that effectively prevents NPs from internalization. The inhibiting effect is found to depend on the membrane-NP attraction, skeleton tension and relative size of the NP to the membrane skeleton mesh. However, our simulations also demonstrate that there are two possibilities for successful internalization of NPs in the presence of the membrane skeleton. The first case is for NPs that has a much smaller size than the dimension of skeleton meshes, and the other is that the skeleton tension is rather weak so that the formed vesicle can still move inward for NP internalization.

  14. Plasmodium falciparum secretome in erythrocyte and beyond

    Directory of Open Access Journals (Sweden)

    Rani eSoni

    2016-02-01

    Full Text Available 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 development of novel anti-malarial therapies.

  15. Mycoplasma gallisepticum Invades Chicken Erythrocytes during Infection▿

    Science.gov (United States)

    Vogl, Gunther; Plaickner, Astrid; Szathmary, Susan; Stipkovits, László; Rosengarten, Renate; Szostak, Michael P.

    2008-01-01

    Recently, it was demonstrated using in vitro assays that the avian pathogen Mycoplasma gallisepticum is able to invade nonphagocytic cells. It was also shown that this mycoplasma can survive and multiply intracellularly for at least 48 h and that this cell invasion capacity contributes to the systemic spread of M. gallisepticum from the respiratory tract to the inner organs. Using the gentamicin invasion assay and a differential immunofluorescence technique combined with confocal laser scanning microscopy, we were able to demonstrate in in vitro experiments that M. gallisepticum is also capable of invading sheep and chicken erythrocytes. The frequencies of invasion of three well-defined M. gallisepticum strains were examined over a period of 24 h, and a significant increase in invasiveness occurred after 8 h of infection. In addition, blood samples derived from chickens experimentally infected via the aerosol route with the virulent strain M. gallisepticum Rlow were analyzed. Surprisingly, M. gallisepticum Rlow was detected in the bloodstream of infected chickens by nested PCR, as well as by differential immunofluorescence and interference contrast microscopy that showed that mycoplasmas were not only on the surface but also inside chicken erythrocytes. This finding provides novel insight into the pathomechanism of M. gallisepticum and may have implications for the development of preventive strategies. PMID:17954728

  16. Mycoplasma gallisepticum invades chicken erythrocytes during infection.

    Science.gov (United States)

    Vogl, Gunther; Plaickner, Astrid; Szathmary, Susan; Stipkovits, László; Rosengarten, Renate; Szostak, Michael P

    2008-01-01

    Recently, it was demonstrated using in vitro assays that the avian pathogen Mycoplasma gallisepticum is able to invade nonphagocytic cells. It was also shown that this mycoplasma can survive and multiply intracellularly for at least 48 h and that this cell invasion capacity contributes to the systemic spread of M. gallisepticum from the respiratory tract to the inner organs. Using the gentamicin invasion assay and a differential immunofluorescence technique combined with confocal laser scanning microscopy, we were able to demonstrate in in vitro experiments that M. gallisepticum is also capable of invading sheep and chicken erythrocytes. The frequencies of invasion of three well-defined M. gallisepticum strains were examined over a period of 24 h, and a significant increase in invasiveness occurred after 8 h of infection. In addition, blood samples derived from chickens experimentally infected via the aerosol route with the virulent strain M. gallisepticum R(low) were analyzed. Surprisingly, M. gallisepticum R(low) was detected in the bloodstream of infected chickens by nested PCR, as well as by differential immunofluorescence and interference contrast microscopy that showed that mycoplasmas were not only on the surface but also inside chicken erythrocytes. This finding provides novel insight into the pathomechanism of M. gallisepticum and may have implications for the development of preventive strategies.

  17. Lessons learned from cloning dogs.

    Science.gov (United States)

    Kim, M J; Oh, H J; Kim, G A; Park, J E; Park, E J; Jang, G; Ra, J C; Kang, S K; Lee, B C

    2012-08-01

    The aim of this article is to review dog cloning research and to suggest its applications based on a discussion about the normality of cloned dogs. Somatic cell nuclear transfer was successfully used for production of viable cloned puppies despite limited understanding of in vitro dog embryo production. Cloned dogs have similar growth characteristics to those born from natural fertilization, with no evidence of serious adverse effects. The offspring of cloned dogs also have similar growth performance and health to those of naturally bred puppies. Therefore, cloning in domestic dogs can be applied as an assisted reproductive technique to conserve endangered species, to treat sterile canids or aged dogs, to improve reproductive performance of valuable individuals and to generate disease model animals. © 2012 Blackwell Verlag GmbH.

  18. Plasmodium falciparum STEVOR proteins impact erythrocyte mechanical properties

    Science.gov (United States)

    Sanyal, Sohini; Egée, Stéphane; Bouyer, Guillaume; Perrot, Sylvie; Safeukui, Innocent; Bischoff, Emmanuel; Buffet, Pierre; Deitsch, Kirk W.; Mercereau-Puijalon, Odile; David, Peter H.

    2012-01-01

    Infection of erythrocytes with the human malaria parasite, Plasmodium falciparum, results in dramatic changes to the host cell structure and morphology. The predicted functional localization of the STEVOR proteins at the erythrocyte surface suggests that they may be involved in parasite-induced modifications of the erythrocyte membrane during parasite development. To address the biologic function of STEVOR proteins, we subjected a panel of stevor transgenic parasites and wild-type clonal lines exhibiting different expression levels for stevor genes to functional assays exploring parasite-induced modifications of the erythrocyte membrane. Using this approach, we show that stevor expression impacts deformability of the erythrocyte membrane. This process may facilitate parasite sequestration in deep tissue vasculature. PMID:22106347

  19. Adaptation of the genetically tractable malaria pathogen Plasmodium knowlesi to continuous culture in human erythrocytes

    KAUST Repository

    Moon, Robert

    2012-12-24

    Research into the aetiological agent of the most widespread form of severe malaria, Plasmodium falciparum, has benefitted enormously from the ability to culture and genetically manipulate blood-stage forms of the parasite in vitro. However, most malaria outside Africa is caused by a distinct Plasmodium species, Plasmodium vivax, and it has become increasingly apparent that zoonotic infection by the closely related simian parasite Plasmodium knowlesi is a frequent cause of life-threatening malaria in regions of southeast Asia. Neither of these important malarial species can be cultured in human cells in vitro, requiring access to primates with the associated ethical and practical constraints. We report the successful adaptation of P. knowlesi to continuous culture in human erythrocytes. Human-adapted P. knowlesi clones maintain their capacity to replicate in monkey erythrocytes and can be genetically modified with unprecedented efficiency, providing an important and unique model for studying conserved aspects of malarial biology as well as species-specific features of an emerging pathogen.

  20. Erythrocyte selenium concentration as a marker of selenium status.

    Science.gov (United States)

    Stefanowicz, Fiona A; Talwar, Dinesh; O'Reilly, Denis S J; Dickinson, Natalie; Atkinson, John; Hursthouse, Andrew S; Rankin, Jean; Duncan, Andrew

    2013-10-01

    Plasma selenium concentration and glutathione peroxidase (GPx) activity are commonly used as markers of selenium nutritional status. However, plasma selenium concentrations fall independently of selenium status during the acute phase response and GPx is analytically problematic. The assay for erythrocyte selenium is robust and concentrations are unaffected by the systemic inflammatory response. This study was performed to investigate the validity of erythrocyte selenium measurement in assessing selenium status. C-reactive protein (CRP), plasma and erythrocyte selenium concentrations and GPx activity were measured in 96 women from two regions of Malawi with low and high selenium dietary intakes. CRP and plasma and erythrocyte selenium was measured in 91 critically ill patients with a systemic inflammatory response. The median CRP value of all subjects from Malawi was 4.2 mg/L indicating no inflammation. The median CRP value for the critically ill patients was 126 mg/L indicating this group was inflamed. In the non-inflamed population there was a strong positive correlation (r = 0.95) between erythrocyte and plasma selenium and a strong positive correlation (r = 0.77) between erythrocyte selenium and erythrocyte GPx up to 6.10 nmol/g Hb after which maximal activity was reached. In the inflamed population, plasma selenium was low, erythrocyte selenium was normal and there was a weak correlation (r = 0.30) between selenium concentrations in plasma and erythrocytes. This demonstrates that plasma selenium is affected by the inflammatory response while erythrocyte selenium concentration is unaffected and can be used to reliably assess selenium status across a wide range of selenium intakes. Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  1. Human cloning and child welfare.

    Science.gov (United States)

    Burley, J; Harris, J

    1999-01-01

    In this paper we discuss an objection to human cloning which appeals to the welfare of the child. This objection varies according to the sort of harm it is expected the clone will suffer. The three formulations of it that we will consider are: 1. Clones will be harmed by the fearful or prejudicial attitudes people may have about or towards them (H1); 2. Clones will be harmed by the demands and expectations of parents or genotype donors (H2); 3. Clones will be harmed by their own awareness of their origins, for example the knowledge that the genetic donor is a stranger (H3). We will show why these three versions of the child welfare objection do not necessarily supply compelling reasons to ban human reproductive cloning. The claim that we will develop and defend in the course of our discussion is that even if it is the case that a cloned child will suffer harms of the type H1-H3, it is none the less permissible to conceive by cloning so long as these cloning-induced welfare deficits are not such as to blight the existence of the resultant child, whoever this may be. PMID:10226914

  2. Antibodies from malaria-exposed pregnant women recognize trypsin resistant epitopes on the surface of Plasmodium falciparum-infected erythrocytes selected for adhesion to chondroitin sulphate A

    Directory of Open Access Journals (Sweden)

    Staalsoe Trine

    2004-09-01

    Full Text Available Abstract Background The ability of Plasmodium falciparum-infected erythrocytes to adhere to the microvasculature endothelium is thought to play a causal role in malaria pathogenesis. Cytoadhesion to endothelial receptors is generally found to be highly sensitive to trypsinization of the infected erythrocyte surface. However, several studies have found that parasite adhesion to placental receptors can be markedly less sensitive to trypsin. This study investigates whether chondroitin sulphate A (CSA binding parasites express trypsin-resistant variant surface antigens (VSA that bind female-specific antibodies induced as a result of pregnancy associated malaria (PAM. Methods Fluorescence activated cell sorting (FACS was used to measure the levels of adult Scottish and Ghanaian male, and Ghanaian pregnant female plasma immunoglobulin G (IgG that bind to the surface of infected erythrocytes. P. falciparum clone FCR3 cultures were used to assay surface IgG binding before and after selection of the parasite for adhesion to CSA. The effect of proteolytic digestion of parasite erythrocyte surface antigens on surface IgG binding and adhesion to CSA and hyaluronic acid (HA was also studied. Results P. falciparum infected erythrocytes selected for adhesion to CSA were found to express trypsin-resistant VSA that are the target of naturally acquired antibodies from pregnant women living in a malaria endemic region of Ghana. However in vitro adhesion to CSA and HA was relatively trypsin sensitive. An improved labelling technique for the detection of VSA expressed by CSA binding isolates has also been described. Conclusion The VSA expressed by CSA binding P. falciparum isolates are currently considered potential targets for a vaccine against PAM. This study identifies discordance between the trypsin sensitivity of CSA binding and surface recognition of CSA selected parasites by serum IgG from malaria exposed pregnant women. Thus, the complete molecular

  3. Erythrocyte diagnosticum as used in revealingmalignant process

    Directory of Open Access Journals (Sweden)

    L. A. Savluchinskayа

    2017-01-01

    Full Text Available A method is proposed for the development of an erythrocyte diagnosticum based on the evidence of patent № 2452501 (10.06.2012 via development of sensitine obtained from the serum of mares in foal, the above factor being used for diagnosis of malignant neoplasms. In order  to reveal the practical significance of the diagnosticum proposed the findings of the testing of the blood serum of 215 patients with variously located tumors and from 67 individuals without malignant tumors are analyzed. Sensitivity of the method was 88 %, specificity – 89 %,  accuracy – 89 %. The accessibility of the method proposed and simplicity of the reaction as well as the rapid response make it possible to use the method under discussion in any medical institution individually or in the course of screening to obtain primary diagnosis or to reveal risk groups.

  4. Deformability of Erythrocytes and Oxidative Damage in Alzheimer Disease

    Directory of Open Access Journals (Sweden)

    Mukerrem Betul Yerer

    2012-04-01

    Full Text Available Purpose: A lowered cerebral perfusion as a consequence of hemodynamic microcirculatory insufficiency is one of the factors underlying in Alzheimer's disease, which is a neurodegenerative disorder leading to progressive cognitive impairment. Erythrocyte deformability is one of the major factors affecting the microcirculatory hemodynamics which is closely related to the oxidative damage. The aim of this study is to investigate the relationship between the erythrocyte deformability, nitric oxide levels and oxidative stress in Alzheimer's disease. Methods: The blood samples of 30 elderly people in three groups consisting of healthy control and different severities of the disease (low and severe were used. Then the erythrocytes were isolated and the deformability of erythrocytes was determined by Rheodyne SSD evaluating the elongation indexes of the erythrocytes under different shear stress. The catalase, glutathione peroxidase and plasma nitric oxide levels were measured spectrophotometric ally. Results: The plasma nitric oxide levels, catalase activities were found significantly higher and glutathione peroxidase activity was significantly lower in severe Alzheimer's disease patients compared to the control group. However, the deformability of erythrocytes was not significantly affected from these alterations. Conclusion: the oxidant-antioxidant status is dramatically changed in Alzheimer's disease patients with the severity of the disease and similar alterations were seen in the nitric oxide levels without any significant change in erythrocyte deformability. [Cukurova Med J 2012; 37(2.000: 65-75

  5. Erythrocyte sedimentation rate as a marker for coronary heart disease.

    Science.gov (United States)

    Yayan, Josef

    2012-01-01

    Patients with angina pectoris or myocardial infarction frequently present without evidence of cardiac-specific heart enzymes by laboratory analysis or specific pathologic electro-cardiogram findings. The current study analyzed the efficacy of the erythrocyte sedimentation rate as an additional potential indicator for coronary heart disease, the aim being to enable quicker identification of patients with angina pectoris or myocardial infarction so that they can be more rapidly treated. Patients with angina pectoris or myocardial infarction who had undergone a heart catheter examination were included in the study. The diagnosis of acute coronary heart disease was made by the physician who performed coronary angiography. Patients without coronary heart disease were used as a control group. The erythrocyte sedimentation rate was measured in all patients. Patients with angina pectoris or myocardial infarction and an inflammatory or tumor disease were excluded. The erythrocyte sedimentation rate was prolonged in 79 (58.09%) of 136 patients; 69 (50.74%) patients (95% confidence interval ±8.4%, 42.34%-59.14%) had coronary heart disease and a prolonged erythrocyte sedimentation rate. The erythrocyte sedimentation rate was prolonged in ten (7.35%) patients (95% confidence interval ±4.39%, 2.96%-11.74%) without coronary heart disease by coronary angiography. The specificity of the erythrocyte sedimentation rate for coronary heart disease was 70.59% and the sensitivity was 67.65%. Erythrocyte sedimentation rate may be a useful additional diagnostic criterion for coronary heart disease.

  6. Increased dense erythrocytes in flame-burned patients.

    Science.gov (United States)

    Saavedra, Arturo P; Warth, James A; Burke, John F; Norton, Kathryn J; Gelfand, Jeffrey A

    2013-01-01

    We have studied dense erythrocytes separated on Arabinogalactan (Stractan) ultracentrifuged gradients in flame-burned patients and in normal individuals. In each case, the percentage of erythrocytes in the densest layers was increased when compared to age and sex matched controls. Using an in vitro system, we showed that as human whole blood is warmed to 48.6°C, the number of dense erythrocytes increases. In addition, the reduced glutathionine (GSH) content of the densest red blood cells is decreased compared to those in lighter fractions on the same gradient or to dense erythrocytes separated from blood incubated at room temperature. These dense red cells were largely composed of spherocytes and spheroechynocytes, two forms of erythrocytes which have been shown by others to have markedly abnormal flow characteristics in vitro. We have demonstrated that in vivo dense erythrocytes can be generated in the setting of flame burns. Thus, the underlying reason may be oxidant injury as represented by the reduced level of GSH that we found in association with the generation of dense erythrocytes.

  7. Simulation of the osmosis-based drug encapsulation in erythrocytes.

    Science.gov (United States)

    Ge, Duobiao; Zou, Lili; Li, Chengpan; Liu, Sen; Li, Shibo; Sun, Sijie; Ding, Weiping

    2017-09-20

    Drug-loaded erythrocytes have been proposed for the treatment of disease. A common way to load drugs into erythrocytes is to apply osmotic shock. Currently, osmosis-based drug encapsulation is studied mainly experimentally, whereas a related theoretical model is still incomplete. In this study, a set of equations is developed to simulate the osmosis-based drug-encapsulation process. First, the modeling is validated with hemolysis rates and the drug-loaded quantities to be found in the literature. Then, the variation of the erythrocyte volume, formation of the pore on the erythrocyte membrane, and quantities of drug loaded into and hemoglobin released from erythrocytes are studied. Finally, an optimized operating condition for encapsulating drugs is proposed. The results show that the volume of erythrocytes exposed to hypotonic NaCl solution increases first and then abruptly decreases because of the pore formation; afterwards, it again increases and then decreases slowly. In the presence of the pore, the drug is loaded by diffusion, whereas the leak-induced convection goes against the loading. For an allowed 45% hemolysis rate, with a 10% hematocrit, the optimized NaCl concentration is 0.44%, the optimized time for sealing the loaded erythrocytes with hypertonic NaCl solution is at 6.5 s, and the quantity of albumin (drug) loaded is 4.5 mg/ml cells.

  8. Focusing and alignment of erythrocytes in a viscoelastic medium

    Science.gov (United States)

    Go, Taesik; Byeon, Hyeokjun; Lee, Sang Joon

    2017-01-01

    Viscoelastic fluid flow-induced cross-streamline migration has recently received considerable attention because this process provides simple focusing and alignment over a wide range of flow rates. The lateral migration of particles depends on the channel geometry and physicochemical properties of particles. In this study, digital in-line holographic microscopy (DIHM) is employed to investigate the lateral migration of human erythrocytes induced by viscoelastic fluid flow in a rectangular microchannel. DIHM provides 3D spatial distributions of particles and information on particle orientation in the microchannel. The elastic forces generated in the pressure-driven flows of a viscoelastic fluid push suspended particles away from the walls and enforce erythrocytes to have a fixed orientation. Blood cell deformability influences the lateral focusing and fixed orientation in the microchannel. Different from rigid spheres and hardened erythrocytes, deformable normal erythrocytes disperse from the channel center plane, as the flow rate increases. Furthermore, normal erythrocytes have a higher angle of inclination than hardened erythrocytes in the region near the side-walls of the channel. These results may guide the label-free diagnosis of hematological diseases caused by abnormal erythrocyte deformability.

  9. [The discrete horror of cloning].

    Science.gov (United States)

    Guibourg, Ricardo A

    2009-01-01

    The author raises the topic of cloning after the decision of the Argentine government, which concerned for the "dignity of the human person", passed a decree of need and urgency, No. 200/97 (Annex), prohibiting cloning experiments with human beings. Therefore, considering that the topic is so terribly urgent and necessary, the author feels it is timely to consider it.

  10. [Scientific ethics of human cloning].

    Science.gov (United States)

    Valenzuela, Carlos Y

    2005-01-01

    True cloning is fission, budding or other types of asexual reproduction. In humans it occurs in monozygote twinning. This type of cloning is ethically and religiously good. Human cloning can be performed by twinning (TWClo) or nuclear transfer (NTClo). Both methods need a zygote or a nuclear transferred cell, obtained in vitro (IVTec). They are under the IVTec ethics. IVTecs use humans (zygotes, embryos) as drugs or things; increase the risk of malformations; increase development and size of abnormalities and may cause long-term changes. Cloning for preserving extinct (or almost extinct) animals or humans when sexual reproduction is not possible is ethically valid. The previous selection of a phenotype in human cloning violates some ethical principles. NTClo for reproductive or therapeutic purposes is dangerous since it increases the risk for nucleotide or chromosome mutations, de-programming or re-programming errors, aging or malignancy of the embryo cells thus obtained.

  11. Erythrocyte Features for Malaria Parasite Detection in Microscopic Images of Thin Blood Smear: A Review

    Directory of Open Access Journals (Sweden)

    Salam Shuleenda Devi

    2016-12-01

    Full Text Available Microscopic image analysis of blood smear plays a very important role in characterization of erythrocytes in screening of malaria parasites. The characteristics feature of erythrocyte changes due to malaria parasite infection. The microscopic features of the erythrocyte include morphology, intensity and texture. In this paper, the different features used to differentiate the non- infected and malaria infected erythrocyte have been reviewed.

  12. Evidence that Clostridium perfringens theta-toxin induces colloid-osmotic lysis of erythrocytes.

    OpenAIRE

    Harris, R. W.; Sims, P J; Tweten, R K

    1991-01-01

    Clostridium perfringens theta-toxin was shown to lyse target erythrocytes by a colloid-osmotic mechanism. Analysis showed the onset of lysis of erythrocytes by theta-toxin could be temporarily stabilized with 0.3 M sucrose. Flow cytometry analysis of the size distribution of theta-toxin-treated erythrocytes showed swelling of the erythrocytes prior to lysis.

  13. Apolipoprotein M mediates sphingosine-1-phosphate efflux from erythrocytes

    DEFF Research Database (Denmark)

    Christensen, Pernille M.; Bosteen, Markus H.; Hajny, Stefan

    2017-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive lipid implicated in e.g. angiogenesis, lymphocyte trafficking, and endothelial barrier function. Erythrocytes are a main source of plasma S1P together with platelets and endothelial cells. Apolipoprotein M (apoM) in HDL carries 70% of plasma S1P, whereas...... 30% is carried by albumin. The current aim was to investigate the role of apoM in export of S1P from human erythrocytes. Erythrocytes exported S1P more efficiently to HDL than to albumin, particularly when apoM was present in HDL. In contrast, export of sphingosine to HDL was unaffected...

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

    Directory of Open Access Journals (Sweden)

    Giuseppina Di Giacomo

    Full Text Available 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.

  15. Animal cloning: problems and prospects.

    Science.gov (United States)

    Wells, D N

    2005-04-01

    An efficient animal cloning technology would provide many new opportunities for livestock agriculture, human medicine, and animal conservation. Nuclear cloning involves the production of animals that are genetically identical to the donor cells used in a technique known as nuclear transfer (NT). However, at present it is an inefficient process: in cattle, only around 6% of the embryos transferred to the reproductive tracts of recipient cows result in healthy, longterm surviving clones. Of concern are the high losses throughout gestation, during birth and in the post-natal period through to adulthood. Many of the pregnancy losses relate to failure of the placenta to develop and function correctly. Placental dysfunction may also have an adverse influence on postnatal health. These anomalies are probably due to incorrect epigenetic reprogramming of the donor genome following NT, leading to inappropriate patterns of gene expression during the development of clones. Whilst some physiological tests on surviving clones suggest normality, other reports indicate a variety of post-natal clone-associated abnormalities. This variability in outcome may reflect species-specific and/or cloning methodological differences. Importantly, to date it appears that these clone-associated phenotypes are not transmitted to offspring following sexual reproduction. This indicates that they represent epigenetic errors, rather than genetic errors, which are corrected during gametogenesis. Whilst this needs confirmation at the molecular level, it provides initial confidence in the first application of NT in agriculture, namely, the production of small numbers of cloned sires from genetically elite bulls, for natural mating, to effectively disseminate genetic gain. In addition to the animal welfare concerns with the technology, the underlying health of the animals and the consequential effect on food safety are critical aspects that require investigation to gain regulatory and consumer

  16. Differential actions of proteinases and neuraminidase on mammalian erythrocyte surface and its impact on erythrocyte agglutination by concanavalin A.

    Science.gov (United States)

    Sharma, Savita; Gokhale, Sadashiv M

    2012-12-01

    Action of proteinases viz. trypsin and chymotrypsin, and neuraminidase on intact erythrocyte membrane proteins and glycophorins (sialoglycoproteins) exposed to cell surface and its impact on lectin (concanavalin A)-mediated agglutination were studied in Homo sapiens (human), Capra aegagrus hircus (goat) and Bubalus bubalis (buffalo). Membrane proteins and glycophorins analysis by SDS-PAGE as visualized by coomassie brilliant blue and periodic acid-schiff stains, respectively, and agglutination behaviour revealed marked differences: 1) there were prominent dissimilarities in the number and molecular weights of glycophorins in human, goat and buffalo erythrocyte membranes; 2) proteinase action(s) on human and buffalo erythrocyte surface membrane proteins and glycophorins showed similarity but was found different in goat; 3) significant differences in erythrocyte agglutinability with concanavalin A can be attributed to differences in membrane composition and alterations in the surface proteins after enzyme treatment; 4) a direct correlation was found between degradation of glycophorins and concanavalin A agglutinability; 5) action of neuraminidase specifically indicated the negative role of cell surface sialic acids in determining concanavalin A agglutinability of goat and buffalo erythrocytes, similar to human. Present studies clearly indicate that there are some basic differences in human, goat and buffalo erythrocyte membrane proteins, especially with respect to glycophorins, which determine the concanavalin A-mediated agglutination in enzyme treated erythrocytes.

  17. Human cloning: can it be made safe?

    Science.gov (United States)

    Rhind, Susan M; Taylor, Jane E; De Sousa, Paul A; King, Tim J; McGarry, Michelle; Wilmut, Ian

    2003-11-01

    There are continued claims of attempts to clone humans using nuclear transfer, despite the serious problems that have been encountered in cloning other mammals. It is known that epigenetic and genetic mechanisms are involved in clone failure, but we still do not know exactly how. Human reproductive cloning is unethical, but the production of cells from cloned embryos could offer many potential benefits. So, can human cloning be made safe?

  18. Quantum Cloning Machines and the Applications

    OpenAIRE

    Fan, Heng; Wang, Yi-Nan; Jing, Li; Yue, Jie-Dong; Shi, Han-Duo; Zhang, Yong-Liang; Mu, Liang-Zhu

    2013-01-01

    No-cloning theorem is fundamental for quantum mechanics and for quantum information science that states an unknown quantum state cannot be cloned perfectly. However, we can try to clone a quantum state approximately with the optimal fidelity, or instead, we can try to clone it perfectly with the largest probability. Thus various quantum cloning machines have been designed for different quantum information protocols. Specifically, quantum cloning machines can be designed to analyze the securit...

  19. Study of Erythrocyte Indices, Erythrocyte Morphometric Indicators, and Oxygen-Binding Properties of Hemoglobin Hematoporphyrin Patients with Cardiovascular Diseases

    Directory of Open Access Journals (Sweden)

    Victor V. Revin

    2017-01-01

    Full Text Available The current study investigates the functional state of erythrocytes and indices of the oxygen-binding capacity of hemoglobin in blood samples from healthy donors and from patients with coronary artery disease and myocardial infarction before and after treatment. It has been established that, in cardiovascular diseases, erythrocyte morphology and hemoglobin oxygen-transporting disorders are observed. Standard therapy does not result in the restoration of the structure and properties of erythrocytes. The authors believe that it is necessary for future therapeutic treatment to include preparations other than cardiovascular agents to enhance the capacity of hemoglobin to transport oxygen to the tissues.

  20. Membrane function alterations in erythrocytes from mood disorder ...

    African Journals Online (AJOL)

    mole: mole) ratio and the altered temperature-dependent activity coefficients of erythrocyte membrane AChE and elevated plasma BChE activities could serve as useful diagnostic pointers for mood disorders. Keywords:Membrane function ...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  2. Erythrocyte oxidative stress markers in children with sickle cell disease

    Directory of Open Access Journals (Sweden)

    Priscila Bacarin Hermann

    2016-07-01

    Conclusions: Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients.

  3. Cryo scanning electron microscopy of Plasmodium falciparum-infected erythrocytes.

    Science.gov (United States)

    Hempel, Casper

    2017-07-01

    Plasmodium falciparum invades erythrocytes as an essential part of their life cycle. While living inside erythrocytes, the parasite remodels the cell's intracellular organization as well as its outer surface. Late trophozoite-stage parasites and schizonts introduce numerous small protrusions on the erythrocyte surface, called knobs. Current methods for studying these knobs include atomic force microscopy and electron microscopy. Standard electron microscopy methods rely on chemical fixation and dehydration modifying cell size. Here, a novel method is presented using rapid freezing and scanning electron microscopy under cryogenic conditions allowing for high resolution and magnification of erythrocytes. This novel technique can be used for precise estimates of knob density and for studies on cytoadhesion. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  4. Immune Evasion Strategies of Pre-Erythrocytic Malaria Parasites

    Directory of Open Access Journals (Sweden)

    Hong Zheng

    2014-01-01

    Full Text Available Malaria is a mosquito-borne infectious disease of humans. It begins with a bite from an infected female Anopheles mosquito and leads to the development of the pre-erythrocytic and blood stages. Blood-stage infection is the exclusive cause of clinical symptoms of malaria. In contrast, the pre-erythrocytic stage is clinically asymptomatic and could be an excellent target for preventive therapies. Although the robust host immune responses limit the development of the liver stage, malaria parasites have also evolved strategies to suppress host defenses at the pre-erythrocytic stage. This paper reviews the immune evasion strategies of malaria parasites at the pre-erythrocytic stage, which could provide us with potential targets to design prophylactic strategies against malaria.

  5. [VISCOELASTISITY AND ELECTRICAL PARAMETERS OF ERYTHROCYTES IN GILBERT SYNDROME].

    Science.gov (United States)

    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.

  6. [Erythrocyte membrane in Duchenne muscular dystrophy. III. Modifications of acetylcholinesterase].

    Science.gov (United States)

    Campagnoli, P; Leporoni, B; Bravi, S; Lenaz, G

    1980-12-15

    Membrane-bound acetylcholinesterase was assayed in erythrocyte ghosts from patients with Duchenne Muscular Distrophy and from the members of their family. Modifications was observed both in Km and Vmax, indicating changes in conformations of the enzyme.

  7. Limitations on Cloning in Classical Mechanics

    OpenAIRE

    Fenyes, Aaron

    2010-01-01

    In this paper, we show that a result precisely analogous to the traditional quantum no-cloning theorem holds in classical mechanics. This classical no-cloning theorem does not prohibit classical cloning, we argue, because it is based on a too-restrictive definition of cloning. Using a less popular, more inclusive definition of cloning, we give examples of classical cloning processes. We also prove that a cloning machine must be at least as complicated as the object it is supposed to clone.

  8. Therapeutic cloning in the mouse

    Science.gov (United States)

    Mombaerts, Peter

    2003-01-01

    Nuclear transfer technology can be applied to produce autologous differentiated cells for therapeutic purposes, a concept termed therapeutic cloning. Countless articles have been published on the ethics and politics of human therapeutic cloning, reflecting the high expectations from this new opportunity for rejuvenation of the aging or diseased body. Yet the research literature on therapeutic cloning, strictly speaking, is comprised of only four articles, all in the mouse. The efficiency of derivation of embryonic stem cell lines via nuclear transfer is remarkably consistent among these reports. However, the efficiency is so low that, in its present form, the concept is unlikely to become widespread in clinical practice. PMID:12949262

  9. Human therapeutic cloning (NTSC): applying research from mammalian reproductive cloning.

    Science.gov (United States)

    French, Andrew J; Wood, Samuel H; Trounson, Alan O

    2006-01-01

    Human therapeutic cloning or nuclear transfer stem cells (NTSC) to produce patient-specific stem cells, holds considerable promise in the field of regenerative medicine. The recent withdrawal of the only scientific publications claiming the successful generation of NTSC lines afford an opportunity to review the available research in mammalian reproductive somatic cell nuclear transfer (SCNT) with the goal of progressing human NTSC. The process of SCNT is prone to epigenetic abnormalities that contribute to very low success rates. Although there are high mortality rates in some species of cloned animals, most surviving clones have been shown to have normal phenotypic and physiological characteristics and to produce healthy offspring. This technology has been applied to an increasing number of mammals for utility in research, agriculture, conservation, and biomedicine. In contrast, attempts at SCNT to produce human embryonic stem cells (hESCs) have been disappointing. Only one group has published reliable evidence of success in deriving a cloned human blastocyst, using an undifferentiated hESC donor cell, and it failed to develop into a hESC line. When optimal conditions are present, it appears that in vitro development of cloned and parthenogenetic embryos, both of which may be utilized to produce hESCs, may be similar to in vitro fertilized embryos. The derivation of ESC lines from cloned embryos is substantially more efficient than the production of viable offspring. This review summarizes developments in mammalian reproductive cloning, cell-to-cell fusion alternatives, and strategies for oocyte procurement that may provide important clues facilitating progress in human therapeutic cloning leading to the successful application of cell-based therapies utilizing autologous hESC lines.

  10. Transbilayer movement of various phosphatidylcholine species in intact human erythrocytes

    OpenAIRE

    van Meer, G.; op den Kamp, J.A.F.

    1982-01-01

    Phosphatidylcholine specific phospholipid exchange protein was used to introduce (14C)-labeled phosphatidylcholine of different fatty acyl compositions into the intact human erythrocyte. Hydrolysis by a combination of phospholipase A2 and sphingomyelinase was applied to prove that originally all newly introduced phosphatidylcholine resided in the outer monolayer. Subsequently the erythrocytes were reincubated at 37°C, and redistribution of the introduced (14C)phosphatidylcholine was monitored...

  11. Kinetics of extracellular ATP in mastoparan 7-activated human erythrocytes

    Science.gov (United States)

    Denis, María Florencia Leal; Incicco, J. Jeremías; Espelt, María Victoria; Verstraeten, Sandra V.; Pignataro, Omar P.; Lazarowski, Eduardo R.; Schwarzbaum, Pablo J.

    2014-01-01

    SUMMARY Background The peptide mastoparan 7 (MST7) stimulated ATP release in human erythrocytes. We explored intra- and extracellular processes governing the time-dependent accumulation of extracellular ATP (i.e., ATPe kinetics). Methods Human erythrocytes were treated with MST7 in the presence or absence of two blockers of pannexin 1. ATPe concentration was monitored by luciferin-luciferase based real-time luminometry. Results Exposure of human erythrocytes to MST7 led to an acute increase in [ATPe], followed by a slower increase phase. ATPe kinetics reflected a strong activation of ATP efflux and a low rate of ATPe hydrolysis by ectoATPase activity. Enhancement of [ATPe] by MST7 required adhesion of erythrocytes to poly-D-lysin-coated coverslips, and correlated with a 31% increase of cAMP and 10% cell swelling. However, when MST7 was dissolved in a hyperosmotic medium to block cell swelling, ATPe accumulation was inhibited by 49%. Erythrocytes pre-exposure to 10 μM of either carbenoxolone or probenecid, two blockers of pannexin 1, exhibited a partial reduction of ATP efflux. Erythrocytes from pannexin 1 knockout mice exhibited similar ATPe kinetics as those of wild type mice erythrocytes exposed to pannexin 1 blockers. Conclusions MST7 induced release of ATP required either cell adhesion or strong activation of cAMP synthesis. Part of this release required cell swelling. Kinetic analysis and a data driven model suggested that ATP efflux is mediated by two ATP conduits displaying different kinetics, with one conduit being fully blocked by pannexin 1 blockers. General Significance Kinetic analysis of extracellular ATP accumulation from human erythrocytes and potential effects on microcirculation. PMID:23742824

  12. Insulin causes insulin-receptor internalization in human erythrocyte ghosts.

    OpenAIRE

    Kelleher, R S; Murray, E F; Peterson, S W

    1987-01-01

    The effect of incubation with insulin on insulin-receptor internalization by erythrocyte ghosts was investigated. The number of surface insulin receptors decreased by 30-40% after incubation of ghosts with insulin. Total insulin-receptor binding to solubilized ghosts was the same in insulin-incubated and control ghosts, whereas insulin binding to an internal vesicular fraction was substantially increased in insulin-incubated ghosts. Our findings suggest that erythrocyte-ghost insulin receptor...

  13. [Comparative estimation of morphofunction characteristics alive and fixed erythrocytes].

    Science.gov (United States)

    Skorkina, M Iu; Fedorova, M Z; Cherniavskikh, S D; Zabiniakov, N A; Sladkova, E A

    2011-01-01

    The method of power spectroscopy carries out the quantitative analysis of elastic properties of alive cells. It has been established that the highest indicators of elasticity nuclear (amphibious) and denuclearized (mammals) alive erythrocytes are registered in epi- and perinuclear space. When fixing with methanol and drying of cells the greatest values of the elastic modulus are displaced to the periphery of the cells. The revealed inversion of elasticity properties of erythrocytes must be considered when assessing the morphofunction characteristics of the fixed cells.

  14. Low toxicity method of inhibiting sickling of sickle erythrocytes

    Science.gov (United States)

    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.

  15. Insulin binding to erythrocytes after acute 16-methyleneprednisolone ingestion.

    Science.gov (United States)

    Dwenger, A; Holle, W; Zick, R; Trautschold, I

    1982-10-01

    The binding of [125I]insulin to erythrocytes, glucose and insulin were determined before and 1, 7 and 35 days after ingestion of 2 X 60-methyleneprednisolone. None of two groups of volunteers (7 males, 4 females showed clear alterations of the insulin binding parameters (Ka and R0), or of the fasting cortisol, glucose and insulin concentrations. These results exclude the possibility that the diabetogenic effect of glucocorticoides is accompanied by an alteration of the insulin receptor characteristics of erythrocytes.

  16. Birth of clones of the world's first cloned dog.

    Science.gov (United States)

    Kim, Min Jung; Oh, Hyun Ju; Kim, Geon A; Setyawan, Erif Maha Nugraha; Choi, Yoo Bin; Lee, Seok Hee; Petersen-Jones, Simon M; Ko, CheMyong J; Lee, Byeong Chun

    2017-11-10

    Animal cloning has gained popularity as a method to produce genetically identical animals or superior animals for research or industrial uses. However, the long-standing question of whether a cloned animal undergoes an accelerated aging process is yet to be answered. As a step towards answering this question, we compared longevity and health of Snuppy, the world's first cloned dog, and its somatic cell donor, Tai, a male Afghan hound. Briefly, both Snuppy and Tai were generally healthy until both developed cancer to which they succumbed at the ages of 10 and 12 years, respectively. The longevity of both the donor and the cloned dog was close to the median lifespan of Afghan hounds which is reported to be 11.9 years. Here, we report creation of 4 clones using adipose-derived mesenchymal stem cells from Snuppy as donor cells. Clinical and molecular follow-up of these reclones over their lives will provide us with a unique opportunity to study the health and longevity of cloned animals compared with their cell donors.

  17. AMPKα1 Deletion Shortens Erythrocyte Life Span in Mice

    Science.gov (United States)

    Wang, Shaobin; Dale, George L.; Song, Ping; Viollet, Benoit; Zou, Ming-hui

    2010-01-01

    AMP-activated protein kinase (AMPK) is an energy sensor essential for maintaining cellular energy homeostasis. Here, we report that AMPKα1 is the predominant isoform of AMPK in murine erythrocytes and mice globally deficient in AMPKα1 (AMPKα1−/−), but not in those lacking AMPKα2, and the mice had markedly enlarged spleens with dramatically increased proportions of Ter119-positive erythroid cells. Blood tests revealed significantly decreased erythrocyte and hemoglobin levels with increased reticulocyte counts and elevated plasma erythropoietin concentrations in AMPKα1−/− mice. The life span of erythrocytes from AMPKα1−/− mice was less than that in wild-type littermates, and the levels of reactive oxygen species and oxidized proteins were significantly increased in AMPKα1−/− erythrocytes. In keeping with the elevated oxidative stress, treatment of AMPKα1−/− mice with the antioxidant, tempol, resulted in decreased reticulocyte counts and improved erythrocyte survival. Furthermore, the expression of Foxo3 and reactive oxygen species scavenging enzymes was significantly decreased in erythroblasts from AMPKα1−/− mice. Collectively, these results establish an essential role for AMPKα1 in regulating oxidative stress and life span in erythrocytes. PMID:20392689

  18. Stimulation of Suicidal Erythrocyte Death by the Antimalarial Drug Mefloquine

    Directory of Open Access Journals (Sweden)

    Rosi Bissinger

    2015-07-01

    Full Text Available Background: The antimalarial drug mefloquine has previously been shown to stimulate apoptosis of nucleated cells. Similar to apoptosis, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include oxidative stress, increase of cytosolic Ca2+-activity ([Ca2+]i, and ceramide. Methods: 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, [Ca2+]i from Fluo3-fluorescence, and ceramide abundance from specific antibody binding. Results: A 48 h treatment of human erythrocytes with mefloquine significantly increased the percentage of annexin-V-binding cells (≥5 µg/ml, significantly decreased forward scatter (≥5 µg/ml, significantly increased ROS abundance (5 µg/ml, significantly increased [Ca2+]i (7.5 µg/ml and significantly increased ceramide abundance (10 µg/ml. The up-regulation of annexin-V-binding following mefloquine treatment was significantly blunted but not abolished by removal of extracellular Ca2+. Even in the absence of extracellular Ca2+, mefloquine significantly increased annexin-V-binding. Conclusions: Mefloquine treatment leads to erythrocyte shrinkage and erythrocyte membrane scrambling, effects at least partially due to induction of oxidative stress, increase of [Ca2+]i and up-regulation of ceramide abundance.

  19. Platelet inhibition by nitrite is dependent on erythrocytes and deoxygenation.

    Directory of Open Access Journals (Sweden)

    Sirada Srihirun

    Full Text Available Nitrite is a nitric oxide (NO metabolite in tissues and blood, which can be converted to NO under hypoxia to facilitate tissue perfusion. Although nitrite is known to cause vasodilation following its reduction to NO, the effect of nitrite on platelet activity remains unclear. In this study, the effect of nitrite and nitrite+erythrocytes, with and without deoxygenation, on platelet activity was investigated.Platelet aggregation was studied in platelet-rich plasma (PRP and PRP+erythrocytes by turbidimetric and impedance aggregometry, respectively. In PRP, DEANONOate inhibited platelet aggregation induced by ADP while nitrite had no effect on platelets. In PRP+erythrocytes, the inhibitory effect of DEANONOate on platelets decreased whereas nitrite at physiologic concentration (0.1 µM inhibited platelet aggregation and ATP release. The effect of nitrite+erythrocytes on platelets was abrogated by C-PTIO (a membrane-impermeable NO scavenger, suggesting an NO-mediated action. Furthermore, deoxygenation enhanced the effect of nitrite as observed from a decrease of P-selectin expression and increase of the cGMP levels in platelets. The ADP-induced platelet aggregation in whole blood showed inverse correlations with the nitrite levels in whole blood and erythrocytes.Nitrite alone at physiological levels has no effect on platelets in plasma. Nitrite in the presence of erythrocytes inhibits platelets through its reduction to NO, which is promoted by deoxygenation. Nitrite may have role in modulating platelet activity in the circulation, especially during hypoxia.

  20. Cyclin A2 regulates erythrocyte morphology and numbers.

    Science.gov (United States)

    Jayapal, Senthil Raja; Ang, Heather Yin-Kuan; Wang, Chelsia Qiuxia; Bisteau, Xavier; Caldez, Matias J; Xuan, Gan Xiao; Yu, Weimiao; Tergaonkar, Vinay; Osato, Motomi; Lim, Bing; Kaldis, Philipp

    2016-11-16

    Cyclin A2 is an essential gene for development and in haematopoietic stem cells and therefore its functions in definitive erythropoiesis have not been investigated. We have ablated cyclin A2 in committed erythroid progenitors in vivo using erythropoietin receptor promoter-driven Cre, which revealed its critical role in regulating erythrocyte morphology and numbers. Erythroid-specific cyclin A2 knockout mice are viable but displayed increased mean erythrocyte volume and reduced erythrocyte counts, as well as increased frequency of erythrocytes containing Howell-Jolly bodies. Erythroblasts lacking cyclin A2 displayed defective enucleation, resulting in reduced production of enucleated erythrocytes and increased frequencies of erythrocytes containing nuclear remnants. Deletion of the Cdk inhibitor p27 Kip1 but not Cdk2, ameliorated the erythroid defects resulting from deficiency of cyclin A2, confirming the critical role of cyclin A2/Cdk activity in erythroid development. Loss of cyclin A2 in bone marrow cells in semisolid culture prevented the formation of BFU-E but not CFU-E colonies, uncovering its essential role in BFU-E function. Our data unveils the critical functions of cyclin A2 in regulating mammalian erythropoiesis.

  1. Antiplasmodial activities of dyes against Plasmodium falciparum asexual and sexual stages: Contrasted uptakes of triarylmethanes Brilliant green, Green S (E142, and Patent Blue V (E131 by erythrocytes

    Directory of Open Access Journals (Sweden)

    Louis-Jérôme Leba

    2017-12-01

    Full Text Available The search for safe antimalarial compounds acting against asexual symptom-responsible stages and sexual transmission-responsible forms of Plasmodium species is one of the major challenges in malaria elimination programs. So far, among current drugs approved for human use, only primaquine has transmission-blocking activity. The discovery of small molecules targeting different Plasmodium falciparum life stages remains a priority in antimalarial drug research. In this context, several independent studies have recently reported antiplasmodial and transmission-blocking activities of commonly used stains, dyes and fluorescent probes against P. falciparum including chloroquine-resistant isolates. Herein we have studied the antimalarial activities of dyes with different scaffold and we report that the triarylmethane dye (TRAM Brilliant green inhibits the growth of asexual stages (IC50 ≤ 2 μM and has exflagellation-blocking activity (IC50 ≤ 800 nM against P. falciparum reference strains (3D7, 7G8 and chloroquine-resistant clinical isolate (Q206. In a second step we have investigated the antiplasmodial activities of two polysulfonated triarylmethane food dyes. Green S (E142 is weakly active against P. falciparum asexual stage (IC50 ≃ 17 μM whereas Patent Blue V (E131 is inactive in both antimalarial assays. By applying liquid chromatography techniques for the culture supernatant analysis after cell washings and lysis, we report the detection of Brilliant green in erythrocytes, the selective uptake of Green S (E142 by infected erythrocytes, whereas Patent Blue V (E131 could not be detected within non-infected and 3D7-infected erythrocytes. Overall, our results suggest that two polysulfonated food dyes might display different affinity with transporters or channels on infected RBC membrane. Keywords: Antimalarial dyes, Transmission blocking, Triarylmethanes, Drug uptake, Brilliant green, Food dyes

  2. Human cloning and 'posthuman' society.

    Science.gov (United States)

    Blackford, Russell

    2005-01-01

    Since early 1997, when the creation of Dolly the sheep by somatic cell nuclear transfer was announced in Nature, numerous government reports, essays, articles and books have considered the ethical problems and policy issues surrounding human reproductive cloning. In this article, I consider what response a modern liberal society should give to the prospect of human cloning, if it became safe and practical. Some opponents of human cloning have argued that permitting it would place us on a slippery slope to a repugnant future society, comparable to that portrayed in Aldous Huxley's novel, Brave New World. I conclude that, leaving aside concerns about safety, none of the psychological or social considerations discussed in this article provides an adequate policy justification for invoking the state's coercive powers to prevent human cloning.

  3. Human Cloning: Let's Discuss It.

    Science.gov (United States)

    Taras, Loretta; Stavroulakis, Anthea M.; Ortiz, Mary T.

    1999-01-01

    Describes experiences with holding discussions on cloning at a variety of levels in undergraduate biology courses. Discusses teaching methods used and student reactions to the discussions. Contains 12 references. (WRM)

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

    DEFF Research Database (Denmark)

    Stevenson, Liz; Laursen, Erik; Cowan, Graeme J

    2015-01-01

    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 assoc...

  5. Diabetic Erythrocytes Test by Correlation Coefficient

    Science.gov (United States)

    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

  6. Islamic perspectives on human cloning.

    Science.gov (United States)

    Sadeghi, Mahmoud

    2007-01-01

    The present paper seeks to assess various views from Islamic jurists relating to human cloning, which is one of the controversial topics in the recent past. Taking Islamic jurisprudence principles, such as the rule of necessity for self preservation and respect for human beings, the rule of la darar wa la dirar ('the necessity to refrain from causing harm to oneself and others') and the rule of usr wa haraj, one may indicate that if human cloning could not be prohibited, as such, it could still be opposed because it gives way to various harmful consequences, which include family disorder, chaos in the clone's family relationships, physical and mental diseases for clones and suffering of egg donors and surrogate mothers. However with due attention to the fact that the reasons behind the prohibition of abortion only restrict the destruction of human embryos in their post-implantation stages, human cloning for biomedical research and exploitation of stem cells from cloned embryos at the blastocyst stage for therapeutic purposes would be acceptable.

  7. Cloning goes to the movies.

    Science.gov (United States)

    Cormick, Craig

    2006-10-01

    Public attitude research conducted by Biotechnology Australia shows that one of the major sources of information on human reproductive cloning is movies. Traditionally, understanding of new and emerging technologies has come through the mass media but human cloning, being so widely addressed through the popular culture of movies, is more effectively defined by Hollywood than the news media or science media. But how well are the science and social issues of cloning portrayed in box office hits such as The Island, Multiplicity, Star Wars: Attack of the Clones and Jurassic Park? These movies have enormous reach and undoubted influence, and are therefore worth analyzing in some detail. This study looks at 33 movies made between 1971 and 2005 that address human reproductive cloning, and it categorizes the films based on their genre and potential influence. Yet rather than simply rating the quality of the science portrayed, the study compares the key messages in these movies with public attitudes towards cloning, to examine the correlations.

  8. Artificial cloning of domestic animals.

    Science.gov (United States)

    Keefer, Carol L

    2015-07-21

    Domestic animals can be cloned using techniques such as embryo splitting and nuclear transfer to produce genetically identical individuals. Although embryo splitting is limited to the production of only a few identical individuals, nuclear transfer of donor nuclei into recipient oocytes, whose own nuclear DNA has been removed, can result in large numbers of identical individuals. Moreover, clones can be produced using donor cells from sterile animals, such as steers and geldings, and, unlike their genetic source, these clones are fertile. In reality, due to low efficiencies and the high costs of cloning domestic species, only a limited number of identical individuals are generally produced, and these clones are primarily used as breed stock. In addition to providing a means of rescuing and propagating valuable genetics, somatic cell nuclear transfer (SCNT) research has contributed knowledge that has led to the direct reprogramming of cells (e.g., to induce pluripotent stem cells) and a better understanding of epigenetic regulation during embryonic development. In this review, I provide a broad overview of the historical development of cloning in domestic animals, of its application to the propagation of livestock and transgenic animal production, and of its scientific promise for advancing basic research.

  9. Morphological characteristics of urine erythrocytes in children with erythrocyturia

    Directory of Open Access Journals (Sweden)

    V.A. Minakova

    2017-09-01

    Full Text Available Background. Nephropathies with erythrocyturia make up about 1/3 of all diseases of the kidneys and the urinary system, and they have some difficulties in differential diagnostics. Quite often, erythrocyturia is the only symptom of these diseases. In connection with this, determination of its origin is an important task in forming the correct diagnosis. Erythrocyturia in most diseases of the lower urinary tract is not accompanied by proteinuria or the presence of cylinders in the urine. The presence of proteinuria (more than 0.3 g/l or 1 g protein in urine per day, along with the appearance of erythrocytic cylinder in the urine sediment, raises suspicion in favor of glomerular or tubular diseases. Glomerular erythrocytes may be detected by means of urea concentration factor (UCF in the urinary sediment as a preliminary test for the determination of the erythrocyturia site. Erythrocytes that pass through the glomerular membrane have a changed form (dysmorphic. Determination of acanthocytes in the urine (ring-shaped erythrocytes with one or several bulges in the form of bubbles of different sizes and types is a more precise criterion of glomerular nephropathy than the presence of dysmorphic erythrocytes. The purpose of the study was to determine the morphological characteristics of urine erythrocytes in children with erythrocyturia, to improve the quality of differential diagnosis. Materials and methods. Determination of the morphological characteristics of urinary erythrocytes using UCF in 73 patients aged 1 to 18 years, of which 45 (61.6 % are patients with hematuric form of glomerulonephritis, 23 (31.5 % — with hereditary nephritis, and 5 (6.8 % — with dysmetabolic nephropathy. Detection of 50 to 80 % of dysmorphic erythrocytes in the urine sediment and finding in urine of more than 5 % of acanthocytes is a highly sensitive and specific diagnostic criterion for glomerular hematuria. Results. In children with a clinical diagnosis

  10. Towards Clone Detection in UML Domain Models

    DEFF Research Database (Denmark)

    Störrle, Harald

    2010-01-01

    , we discuss how model clones arise by analyzing several practical scenarios. We propose a formal definition of models and clones, that allows us to specify a generic clone detection algorithm. Through a thorough analysis of the detail structure of sample UML domain models, recommendations for clone...

  11. Stimulation of Suicidal Erythrocyte Death by Increased Extracellular Phosphate Concentrations

    Directory of Open Access Journals (Sweden)

    Jakob Voelkl

    2014-02-01

    Full Text Available Background/Aim: Anemia in renal insufficiency results in part from impaired erythrocyte formation due to erythropoietin and iron deficiency. Beyond that, renal insufficiency enhances eryptosis, the suicidal erythrocyte death characterized by phosphatidylserine-exposure at the erythrocyte surface. Eryptosis may be stimulated by increase of cytosolic Ca2+-activity ([Ca2+]i. Several uremic toxins have previously been shown to stimulate eryptosis. Renal insufficiency is further paralleled by increase of plasma phosphate concentration. The present study thus explored the effect of phosphate on erythrocyte death. Methods: Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, and [Ca2+]i from Fluo3-fluorescence. Results: Following a 48 hours incubation, the percentage of phosphatidylserine exposing erythrocytes markedly increased as a function of extracellular phosphate concentration (from 0-5 mM. The exposure to 2 mM or 5 mM phosphate was followed by slight but significant hemolysis. [Ca2+]i did not change significantly up to 2 mM phosphate but significantly decreased at 5 mM phosphate. The effect of 2 mM phosphate on phosphatidylserine exposure was significantly augmented by increase of extracellular Ca2+ to 1.7 mM, and significantly blunted by nominal absence of extracellular Ca2+, by additional presence of pyrophosphate as well as by presence of p38 inhibitor SB203580. Conclusion: Increasing phosphate concentration stimulates erythrocyte membrane scrambling, an effect depending on extracellular but not intracellular Ca2+ concentration. It is hypothesized that suicidal erythrocyte death is triggered by complexed CaHPO4.

  12. Erythrocyte G protein as a novel target for malarial chemotherapy.

    Directory of Open Access Journals (Sweden)

    Sean C Murphy

    2006-12-01

    Full Text Available 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.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 beta-adrenergic agonist-induced signaling. This finding directly demonstrates that erythrocyte Gs is functional and that propranolol, an antagonist of G protein-coupled beta-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 beta2-antagonists. beta-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.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.

  13. Impaired in vitro accumulation of mercury in erythrocytes of acatalasemic mice.

    OpenAIRE

    Yamamoto, Hideki; Ishii, Kunihiko; Meguro, Tadamichi; Taketa,Kazuhisa; Ogata,Masana

    1992-01-01

    In order to elucidate the role of erythrocyte catalase in the accumulation of mercury in erythrocytes, labeled erythrocytes and plasma were prepared by exposing normal and acatalasemic mice to radioactive mercury vapor (203Hg0: 6.8mg/m3) for 30 min. Labeled erythrocytes (or plasma) were mixed with unlabeled plasma (or erythrocytes) of normal or acatalasemic mice and incubated at 0 degrees C for 1 h. After incubation, the radioactivity of mercury in the erythrocytes and the plasma was measured...

  14. Mice Deficient in the Putative Phospholipid Flippase ATP11C Exhibit Altered Erythrocyte Shape, Anemia, and Reduced Erythrocyte Life Span*♦

    Science.gov (United States)

    Yabas, Mehmet; Coupland, Lucy A.; Cromer, Deborah; Winterberg, Markus; Teoh, Narci C.; D'Rozario, James; Kirk, Kiaran; Bröer, Stefan; Parish, Christopher R.; Enders, Anselm

    2014-01-01

    Transmembrane lipid transporters are believed to establish and maintain phospholipid asymmetry in biological membranes; however, little is known about the in vivo function of the specific transporters involved. Here, we report that developing erythrocytes from mice lacking the putative phosphatidylserine flippase ATP11C showed a lower rate of PS translocation in vitro compared with erythrocytes from wild-type littermates. Furthermore, the mutant mice had an elevated percentage of phosphatidylserine-exposing mature erythrocytes in the periphery. Although erythrocyte development in ATP11C-deficient mice was normal, the mature erythrocytes had an abnormal shape (stomatocytosis), and the life span of mature erythrocytes was shortened relative to that in control littermates, resulting in anemia in the mutant mice. Thus, our findings uncover an essential role for ATP11C in erythrocyte morphology and survival and provide a new candidate for the rare inherited blood disorder stomatocytosis with uncompensated anemia. PMID:24898253

  15. Detection of Occult Erythrocytic Membrane Damages upon Pharmacological Exposures

    Directory of Open Access Journals (Sweden)

    P. Yu. Alekseyeva

    2007-01-01

    Full Text Available Blood administration of pharmaceuticals may cause occult effects of these agents on erythrocytic membranes. These effects may damage and cause additional membrane defects, but may strengthen. The type and degree of the effects of an agent were detected by calibrated irreversible electroporation with a pulsed electric field (PEF. The paper considers the erythrocytic membranous effects of a wide concentration range of agents used in anesthesiology, such as esmerone, tracrium, and mar-caine-adrenaline. Under the action of PEF and esmerone at the normal concentration N, the rate of erythrocytic hemolysis increased by several times as compared with the control. The similar effect also occurred when esmerone was added at the concentration C=10N. Tracrium exerted a fixing effect on erythrocytic membranes. Upon a combined exposure to PEF and tracrium in the normal concentration C=N; erythrocytic hemolysis was slow. So was with the concentration C=10N. The rate of hemolysis of the red blood cells subjected to a combined action of marcaine adrenaline at the normal concentration C=N and even at the concentration C=10N and PEF was comparable with the hemolytic rate of the reference suspension. 

  16. Chloramines and hypochlorous acid oxidize erythrocyte peroxiredoxin 2.

    Science.gov (United States)

    Stacey, Melissa M; Peskin, Alexander V; Vissers, Margreet C; Winterbourn, Christine C

    2009-11-15

    Peroxiredoxin 2 (Prx2) is an abundant thiol protein that is readily oxidized in erythrocytes exposed to hydrogen peroxide. We investigated its reactivity in human erythrocytes with hypochlorous acid (HOCl) and chloramines, relevant oxidants in inflammation. Prx2 was oxidized to a disulfide-linked dimer by HOCl, glycine chloramine (GlyCl), and monochloramine (NH(2)Cl) in a dose-dependent manner. In the absence of added glucose, Prx2 and GSH showed similar sensitivities. Second-order rate constants for the reactions of Prx2 with NH(2)Cl and GlyCl were 1.5 x 10(4) and 8 M(-1) s(-1), respectively. The NH(2)Cl value is approximately 10 times higher than that for GSH, whereas Prx2 is approximately 30 times less sensitive than GSH to GlyCl. Thus, the relative sensitivity of Prx2 to GlyCl is greater in the erythrocyte. Oxidation of erythrocyte Prx2 and GSH was less in the presence of glucose, probably because of recycling. High doses of NH(2)Cl resulted in incomplete regeneration of reduced Prx2, suggesting impairment of the recycling mechanism. Our results show that, although HOCl and chloramines are less selective than H(2)O(2), they nevertheless oxidize Prx2. Exposure to these inflammatory oxidants will result in Prx2 oxidation and could compromise the erythrocyte's ability to resist damaging oxidative insult.

  17. MODIFICATION OF ERYTHROCYTE MEMBRANE PROTEINS WITH POLYETHYLENE GLYCOL 1500

    Directory of Open Access Journals (Sweden)

    N. G. Zemlianskykh

    2016-10-01

    Full Text Available The aim of the work was to study the effect of polyethylene glycol PEG-1500 on the Ca2+-ATPase activity and changes in CD44 surface marker expression in human erythrocyte membranes. Determination of the Ca2+-ATPase activity was carried out in sealed erythrocyte ghosts by the level of accumulation of inorganic phosphorus. Changes in the expression of CD44 and amount of CD44+-erythrocytes were evaluated by flow cytometry. The inhibition of Ca2+-ATPase activity and a reduction in the level of CD44 expression and also the decrease in the amount CD44+-cells were found, reflecting a fairly complex restructuring in the membrane-cytoskeleton complex of erythrocytes under the influence of PEG-1500. Effect of PEG-1500 on the surface CD44 marker could be mediated by modification of proteins of membrane-cytoskeleton complex, as indicated by accelerated loss of CD44 in erythrocyte membranes after application of protein cross-linking reagent diamide. Reduced activity of Ca2+-ATPase activity may contribute to the increase in intracellular Ca2+ level and thus leads to a modification of interactions of integral proteins with cytoskeletal components that eventually could result in membrane vesiculation and decreasing in expression of the CD44 marker, which is dynamically linked to the cytoskeleton.

  18. Triggering of suicidal erythrocyte death by uremic toxin indoxyl sulfate

    Science.gov (United States)

    2013-01-01

    Background Anemia in end stage renal disease is attributed to impaired erythrocyte formation due to erythropoietin and iron deficiency. On the other hand, end stage renal disease enhances eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and phosphatidylserine-exposure at the erythrocyte surface. Eryptosis may be triggered by increase of cytosolic Ca2+-activity ([Ca2+]i) and by ceramide, which sensitizes erythrocytes to [Ca2+]i. Mechanisms triggering eryptosis in endstage renal disease remained enigmatic. The present study explored the effect of indoxyl sulfate, an uremic toxin accumulated in blood of patients with chronic kidney disease. Methods Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, ceramide abundance by specific antibodies, hemolysis from hemoglobin release, and [Ca2+]i from Fluo3-fluorescence. Results A 48 hours exposure to indoxyl sulfate significantly increased [Ca2+]i (≥ 300 μM), significantly decreased forward scatter (≥ 300 μM) and significantly increased annexin-V-binding (≥ 50 μM). Indoxyl sulfate (150 μM) induced annexin-V-binding was virtually abolished in the nominal absence of extracellular Ca2+. Indoxyl sulfate (150 μM) further enhanced ceramide abundance. Conclusion Indoxyl sulfate stimulates suicidal erythrocyte death or eryptosis, an effect in large part due to stimulation of extracellular Ca2+entry with subsequent stimulation of cell shrinkage and cell membrane scrambling. PMID:24188099

  19. Stimulation of erythrocyte cell membrane scrambling by amiodarone.

    Science.gov (United States)

    Nicolay, Jan P; Bentzen, Peter J; Ghashghaeinia, Mehrdad; Wieder, Thomas; Lang, Florian

    2007-01-01

    Side effects of amiodarone, an effective antiarrhythmic drug, include anemia, which may be caused by decreased formation or accelerated death of erythrocytes. Suicidal erythrocyte death (eryptosis) is characterized by cell shrinkage and cell membrane scrambling leading to phosphatidylserine exposure at the cell surface. Stimulators of erythrocyte membrane scrambling include increase of cytosolic Ca2+ concentration ([Ca2+]i) following activation of Ca2+-permeable cation channels. Moreover, eryptosis is triggered by ceramide. The present study has been performed to test for an effect of amiodarone on eryptosis. Erythrocytes from healthy volunteers were exposed to amiodarone and phosphatidylserine exposure (annexin V binding), cell volume (forward scatter), [Ca2+]i (Fluo3-dependent fluorescence), and ceramide formation (anti-ceramide-FITC antibody and radioactive labelling) determined by flow cytometry. Exposure of erythrocytes to amiodarone (1 microM) increased [Ca2+]i and triggered annexin V binding, but did not significantly decrease forward scatter and did not significantly influence ceramide formation. Amiodarone augmented the increase of annexin binding following hypertonic shock (addition of 550 mM sucrose) but did not significantly alter the enhanced annexin binding following Cl- removal (replacement with gluconate). Amiodarone did not significantly modify the decrease of forward scatter following hypertonic shock or Cl- removal. The present observations disclose a novel action of amiodarone which may contribute to the side effects of the drug.

  20. Very Deep Convolutional Neural Networks for Morphologic Classification of Erythrocytes.

    Science.gov (United States)

    Durant, Thomas J S; Olson, Eben M; Schulz, Wade L; Torres, Richard

    2017-12-01

    Morphologic profiling of the erythrocyte population is a widely used and clinically valuable diagnostic modality, but one that relies on a slow manual process associated with significant labor cost and limited reproducibility. Automated profiling of erythrocytes from digital images by capable machine learning approaches would augment the throughput and value of morphologic analysis. To this end, we sought to evaluate the performance of leading implementation strategies for convolutional neural networks (CNNs) when applied to classification of erythrocytes based on morphology. Erythrocytes were manually classified into 1 of 10 classes using a custom-developed Web application. Using recent literature to guide architectural considerations for neural network design, we implemented a "very deep" CNN, consisting of >150 layers, with dense shortcut connections. The final database comprised 3737 labeled cells. Ensemble model predictions on unseen data demonstrated a harmonic mean of recall and precision metrics of 92.70% and 89.39%, respectively. Of the 748 cells in the test set, 23 misclassification errors were made, with a correct classification frequency of 90.60%, represented as a harmonic mean across the 10 morphologic classes. These findings indicate that erythrocyte morphology profiles could be measured with a high degree of accuracy with "very deep" CNNs. Further, these data support future efforts to expand classes and optimize practical performance in a clinical environment as a prelude to full implementation as a clinical tool. © 2017 American Association for Clinical Chemistry.

  1. [Mystery and problems of cloning].

    Science.gov (United States)

    Nikitin, V A

    2010-01-01

    The attention of investigators is attracted to the fact that, in spite of great efforts in mammalian cloning, advances that have been made in this area of research are not great, and cloned animals have developmental pathologies often incompatible with life and/or reproduction ability. It is yet not clear what technical or biological factors underlie this, and how they are connected or interact with each other, which is more realistic strategically. There is a great number of articles dealing with the influence of cloning with the nuclear transfer on genetic and epigenetic reprogramming of donor cells. At the same time we can see the practical absence of analytical investigations concerning the technology of cloning as such, its weak points, and possible sources of cellular trauma in the course of microsurgery of nuclear transfer or twinning. This article discusses step by step several nuclear transfer techniques and the methods of dividing early preimplanted embryos for twinning with the aim to reveal possible sources of cell damage during micromanipulation that may have negative influence on the development of cloned organisms. Several new author's technologies based on the study of cell biophysical characteristics are described, which allow one to avoid cellular trauma during manipulation and minimize the possibility of cell damage at any rate.

  2. [Cloning and law in Hungary].

    Science.gov (United States)

    Julesz, Máté

    2015-03-01

    Reproductive human cloning is prohibited in Hungary, as in many other countries. Therapeutic human cloning is not prohibited, just like in many other countries. Stem cell therapy is also allowed. Article III, paragraph (3) of the Hungarian basic law (constitution) strictly forbids total human cloning. Article 1 of the Additional Protocol to the Oviedo Convention, on the Prohibition of Cloning Human Beings (1998) stipulates that any intervention seeking to create a human being genetically identical to another human being, whether living or dead, is prohibited. In Hungary, according to Article 174 of the Criminal Code, total human cloning constitutes a crime. Article 180, paragraph (3) of the Hungarian Act on Health declares that embryos shall not be brought about for research purposes; research shall be conducted only on embryos brought about for reproductive purposes when this is authorized by the persons entitled to decide upon its disposal, or when the embryo is damaged. Article 180, paragraph (5) of the Hungarian Act on Health stipulates that multiple individuals who genetically conform to one another shall not be brought about. According to Article 181, paragraph (1) of the Hungarian Act on Health, an embryo used for research shall be kept alive for not longer than 14 days, not counting the time it was frozen for storage and the time period of research.

  3. Detection of antibodies to variant antigens on Plasmodium falciparum-infected erythrocytes by flow cytometry

    DEFF Research Database (Denmark)

    Staalsoe, T; Giha, H A; Dodoo, D

    1999-01-01

    BACKGROUND: Naturally induced antibodies binding to surface antigens of Plasmodium falciparum-infected erythrocytes can be detected by direct agglutination of infected erythrocytes or by indirect immunofluorescence on intact, unfixed, infected erythrocytes. Agglutinating antibodies have previously...

  4. Supernatant of Aged Erythrocytes Causes Lung Inflammation and Coagulopathy in a "Two-Hit" In Vivo Syngeneic Transfusion Model

    NARCIS (Netherlands)

    Vlaar, Alexander P. J.; Hofstra, Jorrit J.; Levi, Marcel; Kulik, Willem; Nieuwland, Rienk; Tool, Anton T. J.; Schultz, Marcus J.; de Korte, Dirk; Juffermans, Nicole P.

    2010-01-01

    Background: Transfusion of erythrocytes is associated with increased morbidity in certain patient groups. Storage time of erythrocytes may contribute to respiratory complications. Using a syngeneic in vivo transfusion model, we investigated whether transfusion of stored rat erythrocytes causes lung

  5. Public perceptions of animal cloning

    DEFF Research Database (Denmark)

    Jelsøe, Erling; Vincentsen, Ulla; Andersen, Ida-Elisabeth

    What was from the outset meant to be a survey testing predefined categories of ethical positions related to new biotechnologies with animal cloning as an example was subsequently developed into a process of broader involvement of groups of citizens in the issue. The survey was conducted at meetings...... in four different cities in Denmark. The participants were introduced to animal cloning and after that they filled out the questionnaire. Finally, the issue was discussed in focus groups. The process as a whole was run in a dialogue oriented way. Through the information they received in combination...... with reflecting on the survey questions the participants were well prepared for discussions in the focus groups. This approach made it possible, on the one hand to get a measure of the citizen's perceptions of the ethical aspects of animal cloning, but also to go deeper into their own thoughts of the issue...

  6. A novel approach for assessments of erythrocyte sedimentation rate.

    Science.gov (United States)

    Pribush, A; Hatskelzon, L; Meyerstein, N

    2011-06-01

    Previous studies have shown that the dispersed phase of sedimenting blood undergoes dramatic structural changes: Discrete red blood cell (RBC) aggregates formed shortly after a settling tube is filled with blood are combined into a continuous network followed by its collapse via the formation of plasma channels, and finally, the collapsed network is dispersed into individual fragments. Based on this scheme of structural transformation, a novel approach for assessments of erythrocyte sedimentation is suggested. Information about erythrocyte sedimentation is extracted from time records of the blood conductivity measured after a dispersion of RBC network into individual fragments. It was found that the sedimentation velocity of RBC network fragments correlates positively with the intensity of attractive intercellular interactions, whereas no effect of hematocrit (Hct) was observed. Thus, unlike Westergren erythrocyte sedimentation rate, sedimentation data obtained by the proposed method do not require correction for Hct. © 2010 Blackwell Publishing Ltd.

  7. Genotoxic Biomarkers in Erythrocytes of Lepidochelys olivacea (Cheloniidae from Colombia

    Directory of Open Access Journals (Sweden)

    Victor Hugo Quiroz Herrera

    2017-09-01

    Full Text Available This research was conducted in the municipality of Bahia Solano, Colombia, and had as a goal to detect damage erythrocytes circulating with nuclear lesions in fifty-five Olive Ridley adult females using acridine orange immunostain, and correlate its frequencies with some physiological and biometric parameters. We determine a micronucleated erythrocytes (MNE frequency of 0.6 ± 0.6 and nuclear buds (NBE of 2.1 ± 1.9. We not found any relationship between the nuclear lesions with physiological or biometric parameters evaluated (Pearson and Kruskal-Wallis, p<0.05. We define a significative statistical difference (p=0.035 between both nuclear lesions frequencies. This results show nuclear damages in erythrocytes of Olive Ridley sea turtle for the first time in Colombia as an outcome of genotoxic stress. Also contributes key information for future research in the ecotoxicology area for endangered marine species.

  8. Simulation of dielectric spectra of erythrocytes with various shapes

    Energy Technology Data Exchange (ETDEWEB)

    Asami, Koji, E-mail: asami@e.kuicr.kyoto-u.ac.j [Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)

    2009-07-07

    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.

  9. Determination of somatic mutations in human erythrocytes by cytometry

    Energy Technology Data Exchange (ETDEWEB)

    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.

  10. Segmentation of leukocytes and erythrocytes in blood smear images.

    Science.gov (United States)

    Bergen, Tobias; Steckhan, Dirk; Wittenberg, Thomas; Zerfass, Thorsten

    2008-01-01

    Differential blood count is a standard method in hematological laboratory diagnosis. In the course of developing a computer-assisted microscopy system for the generation of differential blood counts, the detection and segmentation of white and red blood cells forms an essential step and its exactness is a fundamental prerequisite for the effectiveness of the subsequent classification step. We propose a method for the exact segmentation of leukocytes and erythrocytes in a simultaneous and cooperative way. We combine pixel-wise classification with template matching to locate erythrocytes and use a level-set approach in order to get the exact cell contours of leukocyte nucleus and plasma regions as well as erythrocyte regions. An evaluation comparing the performance of the algorithm to the manual segmentation performed by several persons yielded good results.

  11. Identification of Novel Membrane Structures in Plasmodium falciparum Infected Erythrocytes

    Directory of Open Access Journals (Sweden)

    Clavijo Carlos A

    1998-01-01

    Full Text Available Little is known about the molecular mechanisms underlying the release of merozoites from malaria infected erythrocytes. In this study membranous structures present in the culture medium at the time of merozoite release have been characterized. Biochemical and ultrastructural evidence indicate that membranous structures consist of the infected erythrocyte membrane, the parasitophorous vacuolar membrane and a residual body containing electron dense material. These are subcellular compartments expected in a structure that arises as a consequence of merozoite release from the infected cell. Ultrastructural studies show that a novel structure extends from the former parasite compartment to the surface membrane. Since these membrane modifications are detected only after merozoites have been released from the infected erythrocyte, it is proposed that they might play a role in the release of merozoites from the host cell

  12. Formulation and Drug Loading Features of Nano-Erythrocytes

    Science.gov (United States)

    Dong, Xiaoting; Niu, Yawei; Ding, Yi; Wang, Yuemin; Zhao, Jialan; Leng, Wei; Qin, Linghao

    2017-03-01

    Nano erythrocyte ghosts have recently been used as drug carriers of water-soluble APIs due to inherit biological characteristics of good compatibility, low toxicity, and small side-effect. In this study, we developed a novel drug delivery system based on nano erythrocyte ghosts (STS-Nano-RBCs) to transport Sodium Tanshinone IIA sulfonate (STS) for intravenous use in rat. STS-Nano-RBCs were prepared by hypotonic lysis and by extrusion methods, and its biological properties were investigated compared with STS injection. The results revealed that STS-Nano-RBCs have narrow particle size distribution, good drug loading efficiency, and good stability within 21 days. Compared with STS injection, STS-Nano-RBCs extended the drug release time in vitro and in vivo with better repairing effect on oxidative stress-impaired endothelial cells. These results suggest that the nano erythrocyte ghosts system could be used to deliver STS.

  13. The interactions of fibrinogen and dextrans with erythrocytes

    Science.gov (United States)

    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

  14. The topsy-turvy cloning law.

    Science.gov (United States)

    Brassington, Iain; Oultram, Stuart

    2011-03-01

    In debates about human cloning, a distinction is frequently drawn between therapeutic and reproductive uses of the technology. Naturally enough, this distinction influences the way that the law is framed. The general consensus is that therapeutic cloning is less morally problematic than reproductive cloning--one can hold this position while holding that both are morally unacceptable--and the law frequently leaves the way open for some cloning for the sake of research into new therapeutic techniques while banning it for reproductive purposes. We claim that the position adopted by the law has things the wrong way around: if we accept a moral distinction between therapeutic and reproductive cloning, there are actually more reasons to be morally worried about therapeutic cloning than about reproductive cloning. If cloning is the proper object of legal scrutiny, then, we ought to make sure that we are scrutinising the right kind of clone.

  15. [Anti-erythrocyte and anti-HLA immunization in hemoglobinopathies].

    Science.gov (United States)

    Ben Salah, N; El Borgi, W; Ben Lakhal, F; Ben Mansour, M; Gouider, E; Gorgi, Y; Bardi, R; Zoueri, B; Hafsia, R

    2014-12-01

    Evaluate the anti-erythrocyte and anti-HLA immunization rates in hemoglobinopathies. Cross-sectional study (October 2009-March 2010) on 83 patients followed for hemoglobinopathies. The irregular antibodies research is realized by two techniques: indirect Coombs and enzymatic technique on gel cards. The search for anti-HLA class I antibodies is done by complement dependent lymphocytotoxicity. The mean age was 30 years (14-64 years), the sex ratio M/F is 0.84. Our series included 42 cases of sickle cell disease (29 homozygous sickle cell anemia and 13 sickle-thalassemia) and 41 cases of thalassemia syndromes (26 major and 15 intermediate). The anti-erythrocyte alloimmunization rate is 10.84% without difference between thalassemia syndromes and sickle cell disease. The autoimmunization rate (22.89%) is higher in thalassemia syndromes (41.46%) than in the sickle cell disease (7.14%) (P<0.001). The anti-HLA immunization rate is 31.6% without difference between thalassemia syndromes and sickle cell disease. The young age, transfusion at a young age and the total number of transfusions are the factors that increase the risk of anti-erythrocyte autoimmunization. No clinicobiological parameter does influence the anti-erythrocyte and anti-HLA alloimmunization. There is no significant association between anti-erythrocyte and anti-HLA immunization. The erythrocyte and anti-HLA anti-immunization rates are high in our series. Preventive strategy is needed to ensure optimal blood safety. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. Inhibition of Suicidal Erythrocyte Death by Indirubin-3'-Monoxime.

    Science.gov (United States)

    Liu, Chunqiu; Jiang, Peipei; Xu, Yuanhong; Zheng, Meijuan; Qiao, Jinpin; Zhou, Xueyong; Huang, Dake; Bian, Maohong

    2018-01-01

    Qing Dai is a prized traditional Chinese medicine whose major component, indirubin, and its derivative, indirubin-3'-monoxime (IDM), have inhibitory effects on the growth of many human tumor cells and pronounced anti-leukemic activities. However, the effects of IDM on mature human erythrocytes are unclear. This study aimed to evaluate the potential impact of IDM on erythrocytes and the mechanisms underlying that impact. Utilizing flow cytometry and confocal laser scanning microscopy, phosphatidylserine exposure at the cell surface was estimated by annexin V-fluorescein isothiocyanate (FITC). The relative cell size, expressed in arbitrary units, was evaluated by forward scatter in a flow cytometer. Fluo-3 fluorescence was used to bewrite changes in cytosolic Ca2+ activity, reactive oxygen species (ROS) formation was assessed by 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescence, and ceramide abundance was evaluated by FITC-conjugated specific antibodies. The 24-h exposure of human erythrocytes to IDM (12 µM) significantly decreased the percentage of annexin V-binding erythrocytes and the intracellular calcium concentration ([Ca2+]i). IDM (3-12 µM) did not significantly modify the ceramide level or DCFH-DA fluorescence. Energy depletion (removal of glucose for 24 hours) significantly increased annexin V binding and Fluo-3 fluorescence and diminished forward scatter, and these effects were significantly mitigated by IDM (12 µM). Moreover, the Ca2+ ionophore ionomycin (1 µM, 60 min) and oxidative stress (30 min exposure to 0.05 mM tert-butyl hydroperoxide, t-BHP) similarly triggered eryptosis, which was also significantly suppressed by IDM. IDM is a novel inhibitor of suicidal erythrocyte death following ionomycin treatment, t-BHP treatment and energy depletion. Thus, IDM may counteract anemia and impairment of microcirculation, at least in part, by inhibition of Ca2+ entry into erythrocytes. © 2018 The Author(s). Published by S. Karger AG, Basel.

  17. Stimulating Effect of Elvitegravir on Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Rosi Bissinger

    2016-03-01

    Full Text Available Background/Aims: The antiviral drug Elvitegravir is used for the treatment of Human Immunodeficiency Virus (HIV infections. The present study explored whether the drug is able to trigger eryptosis, the suicidal death of erythrocytes. Eryptosis is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i, oxidative stress, ceramide, activated p38 kinase and activated caspases. The present study explored, whether Elvitegravir induces eryptosis and, if so, to shed light on the mechanisms involved. Methods: Phosphatidylserine abundance at the erythrocyte surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, abundance of reactive oxygen species (ROS from DCFDA dependent fluorescence, and ceramide abundance at the erythrocyte surface utilizing specific antibodies. Results: A 48 hours exposure of human erythrocytes to Elvitegravir (≥ 1.5 µg/ml significantly increased the percentage of annexin-V-binding cells, and significantly decreased forward scatter. Elvitegravir (2.5 µg/ml significantly increased Fluo3-fluorescence, but did not significantly modify DCFDA fluorescence or ceramide abundance. The effect of Elvitegravir on annexin-V-binding was significantly blunted by removal of extracellular Ca2+, but not in the presence of p38 kinase inhibitor SB203580 (2 µM or in the presence of pancaspase inhibitor zVAD (10 µM. Conclusions: Elvitegravir triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to entry of extracellular Ca2+.

  18. Erythrocyte Stiffness during Morphological Remodeling Induced by Carbon Ion Radiation

    Science.gov (United States)

    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

  19. Viral erythrocytic necrosis: Chapter 2.2.7

    Science.gov (United States)

    Winton, James R.; Hershberger, Paul K.

    2014-01-01

    Viral erythrocytic necrosis (VEN), originally termed piscine erythrocytic necrosis, is a condition that has been reported to affect the red blood cells (RBCs) of many species of marine and anadromous fishes in both the Atlantic and Pacific Oceans (Nicholson and Reno 1981; Smail 1982; Wolf 1988; Dannevig and Thorud 1999). Fish with VEN may develop a severe anemia that can reduce their stamina, predispose them to other infections or increase the impact of other stressors (MacMillan et al. 1980; Nicholson and Reno 1981; Meyers et al. 1986; Haney et al. 1992) resulting in population-scale impacts in susceptible species (Hershberger et al. 2009).

  20. Electrophysiological studies of malaria parasite-infected erythrocytes: Current status

    Science.gov (United States)

    Staines, Henry M.; Alkhalil, Abdulnaser; Allen, Richard J.; De Jonge, Hugo R.; Derbyshire, Elvira; Egée, Stéphane; Ginsburg, Hagai; Hill, David A.; Huber, Stephan M.; Kirk, Kiaran; Lang, Florian; Lisk, Godfrey; Oteng, Eugene; Pillai, Ajay D.; Rayavara, Kempaiah; Rouhani, Sherin; Saliba, Kevin J.; Shen, Crystal; Solomon, Tsione; Thomas, Serge L. Y.; Verloo, Patrick; Desai, Sanjay A.

    2009-01-01

    The altered permeability characteristics of erythrocytes infected with malaria parasites have been a source of interest for over 30 years. Recent electrophysiological studies have provided strong evidence that these changes reflect transmembrane transport through ion channels in the host erythrocyte plasma membrane. However, conflicting results and differing interpretations of the data have led to confusion in this field. In an effort to unravel these issues, the groups involved recently came together for a week of discussion and experimentation. In this article, the various models for altered transport are reviewed, together with the areas of consensus in the field and those that require a better understanding. PMID:17292372

  1. [Relevance of erythrocyte parameters on fluid management in critical care].

    Science.gov (United States)

    Wang, Zhi-gang; Zhang, Yan; Zhu, Li-hong

    2013-05-01

    To manage fluid therapy in severely ill patients through investigating the relationship between erythrocyte parameters and central venous pressure (CVP) and its denoted blood volume. The research project was divided into two parts. Part I: CVP and concurrent erythrocyte parameters [red blood count (RBC), hemoglobin (Hb), haematocrit (HCT)] were serially recorded in a severely ill patient every morning for 38 days. The obtained values of CVP were divided into three groups (10 cm H2O group), then erythrocyte parameters of each period were compared to obtain the relationship among them. At the same time, "the best" CVP (blood volume was in suitable state) and "the best" erythrocyte parameters (accordingly the blood was not be diluted or concentrated) were obtained. Part II: "the best" CVP and corresponding "the best" erythrocyte parameters were determined in another patient. When the patient's blood volume was in doubt, detected her erythrocyte parameters right away. If the variance between the "practical" and "the best" values was notable, blood volume replenishment or diureses were performed. Then the resulting CVP of fluid expansion or diuresis before and after the treatment were compared, or else other influencing factors should be seeked. Part I: the values of RBC, Hb and HCT in group CVP>10 cm H2O were lower than those of group CVPerythrocyte parameters were determined (RBC was 3.43×10(9)/L, Hb was 97.4 g/L, HCT was 0.310). Part II: "the best" CVP of the this patient was 8 to 10 cm H2O too, accordingly "the best" erythrocyte parameter in term of Hb was 105 g/L. The CVP was obviously elevated in the group in which Hb was higher than "the best" Hb subsequent to fluid expansion (8.29±1.80 cm H2O vs. 5.86±1.57 cm H2O, Perythrocyte parameters, "the best" erythrocyte parameters accompanying "the best" CVP would probably guide fluid therapy best in severely ill patients.

  2. Multiple loci influence erythrocyte phenotypes in the CHARGE Consortium

    OpenAIRE

    Ganesh, Santhi K.; Zakai, Neil A.; van Rooij, Frank J A.; Soranzo, Nicole; Smith, Albert V.; Nalls, Michael A.; Chen, Ming-Huei; Kottgen, Anna; Glazer, Nicole L.; Dehghan, Abbas; Kuhnel, Brigitte; Aspelund, Thor; Yang, Qiong; Tanaka, Toshiko; Jaffe, Andrew

    2009-01-01

    Erythrocyte measures are heritable and have important health implications, yet their genetic determinants are largely unknown. We performed genome-wide association analyses in 24,167 European-ancestry individuals for six erythrocyte traits and identified associations at 23 loci (P values 5?10-8 to 1?10-57). Replication testing in an independent set of 9,456 European-ancestry individuals showed strong evidence of association in all 23 loci in meta-analysis of the discovery and replication coho...

  3. Erythrocyte-derived optical nano-vesicles as theranostic agents

    Science.gov (United States)

    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).

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

    OpenAIRE

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

    2003-01-01

    © 2003 – IOS Press. All rights reserved 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, P50 and erythrocyte deformability and also to verify if the role of adrenaline on erythrocyte properties is sex-dependent. Blood sample...

  5. Python erythrocytes are resistant to α-hemolysin from Escherichia coli.

    Science.gov (United States)

    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. Calpain-1 knockout reveals broad effects on erythrocyte deformability and physiology

    Science.gov (United States)

    Wieschhaus, Adam; Khan, Anwar; Zaidi, Asma; Rogalin, Henry; Hanada, Toshihiko; Liu, Fei; De Franceschi, Lucia; Brugnara, Carlo; Rivera, Alicia; Chishti, Athar H.

    2014-01-01

    Pharmacological inhibitors of cysteine proteases have provided useful insights into the regulation of calpain activity in erythrocytes. However, the precise biological function of calpain activity in erythrocytes remains poorly understood. Erythrocytes express calpain-1, an isoform regulated by calpastatin, the endogenous inhibitor of calpains. In the present study, we investigated the function of calpain-1 in mature erythrocytes using our calpain-1-null [KO (knockout)] mouse model. The calpain-1 gene deletion results in improved erythrocyte deformability without any measurable effect on erythrocyte lifespan in vivo. The calcium-induced sphero-echinocyte shape transition is compromised in the KO erythrocytes. Erythrocyte membrane proteins ankyrin, band 3, protein 4.1R, adducin and dematin are degraded in the calcium-loaded normal erythrocytes but not in the KO erythrocytes. In contrast, the integrity of spectrin and its state of phosphorylation are not affected in the calcium-loaded erythrocytes of either genotype. To assess the functional consequences of attenuated cytoskeletal remodelling in the KO erythrocytes, the activity of major membrane transporters was measured. The activity of the K+–Cl− co-transporter and the Gardos channel was significantly reduced in the KO erythrocytes. Similarly, the basal activity of the calcium pump was reduced in the absence of calmodulin in the KO erythrocyte membrane. Interestingly, the calmodulin-stimulated calcium pump activity was significantly elevated in the KO erythrocytes, implying a wider range of pump regulation by calcium and calmodulin. Taken together, and with the atomic force microscopy of the skeletal network, the results of the present study provide the first evidence for the physiological function of calpain-1 in erythrocytes with therapeutic implications for calcium imbalance pathologies such as sickle cell disease. PMID:22870887

  7. Enhancing blockade of Plasmodium falciparum erythrocyte invasion: assessing combinations of antibodies against PfRH5 and other merozoite antigens.

    Directory of Open Access Journals (Sweden)

    Andrew R Williams

    Full Text Available No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC(50 values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte-binding antigens such as PfRH4, to inhibit the growth of a homologous P. falciparum clone. A combination of antibodies against PfRH4 and basigin, the erythrocyte receptor for PfRH5, also potently inhibited parasite growth. This methodology provides the first quantitative evidence that polyclonal vaccine-induced antibodies can act synergistically against P. falciparum antigens and should help to guide the rational development of future multi-antigen vaccines.

  8. Anti-oxidant activity of holo- and apo-c-phycocyanin and their protective effects on human erythrocytes.

    Science.gov (United States)

    Pleonsil, Pornthip; Soogarun, Suphan; Suwanwong, Yaneenart

    2013-09-01

    This study was conducted to investigate the anti-oxidant activity of the recombinant apo-c-phycocyanin (c-PC) β-subunit compared to native c-PC purified from Spirulina sp. The gene encoding the β-subunit of c-PC was successfully cloned and expressed in Escherichia coli. The anti-oxidant capacities of recombinant apo-c-PC(β) and native c-PC were evaluated by measuring their Trolox equivalent antioxidant capacities and examining their protective effects on erythrocytes from normal and homozygous haemoglobin E individuals against peroxyl radicals and hydrogen peroxide. The results demonstrated that the anti-oxidant capacities are native c-PC≫Trolox>recombinant apo-c-PC(β). Both anti-oxidant proteins can potentially protect erythrocytes from oxidative damage. Expression of c-PC in bacteria reduces the cost and time for protein production, and the recombinant protein could be further developed to obtain a more efficient protein for therapeutic purposes. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Positional cloning of deafness genes

    NARCIS (Netherlands)

    Kremer, H.; Cremers, F.P.M.

    2009-01-01

    The identification of the majority of the known causative genes involved in nonsyndromic sensorineural hearing loss (NSHL) started with linkage analysis as part of a positional cloning procedure. The human and mouse genome projects in combination with technical developments on genotyping,

  10. Kinetics of viral load and erythrocytic inclusion body formation in pacific herring artificially infected with erythrocytic necrosis virus

    Science.gov (United States)

    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.

  11. Janus kinase 3 is expressed in erythrocytes, phosphorylated upon energy depletion and involved in the regulation of suicidal erythrocyte death.

    Science.gov (United States)

    Bhavsar, Shefalee K; Gu, Shuchen; Bobbala, Diwakar; Lang, Florian

    2011-01-01

    Janus kinase 3, a tyrosine kinase expressed in haematopoetic tissues, plays a decisive role in T-lymphocyte survival. JAK3 deficiency leads to (Severe) Combined Immunodeficiency (SCID) resulting from enhanced lymphocyte apoptosis. JAK3 is activated by phosphorylation. Nothing is known about expression of JAK3 in erythrocytes, which may undergo apoptosis-like cell death (eryptosis) characterized by cell membrane scrambling with phosphatidylserine exposure and cell shrinkage. Triggers of eryptosis include energy depletion. The present study utilized immunohistochemistry and confocal microscopy to test for JAK3 expression and phosphorylation, and FACS analysis to determine phosphatidylserine exposure (annexin binding) and cell volume (forward scatter). As a result, JAK3 was expressed in erythrocytes and phosphorylated following 24h and 48h glucose depletion. Forward scatter was slightly but significantly smaller in erythrocytes from JAK3-deficient mice (jak3(-/-)) than in erythrocytes from wild type mice (jak3(+/+)). Annexin V binding was similarly low in both genotypes. The JAK3 inhibitors WHI-P131/JANEX-1 (4-(4'-Hydroxyphenyl)amino-6,7-dimethoxyquinazoline, 156μM) and WHI-P154 (4-[(3'-Bromo-4'-hydroxyphenyl)amino]-6,7-dimethoxyquinazoline, 11.2μM) did not significantly modify annexin V binding or forward scatter. Glucose depletion increased annexin V binding, an effect significantly blunted in jak3(-/-) erythrocytes and in the presence of the JAK3 inhibitors. The observations disclose a completely novel role of Janus kinase 3, i.e. the triggering of cell membrane scrambling in energy depleted erythrocytes. Copyright © 2011 S. Karger AG, Basel.

  12. [Physical essence of erythrocytic sedimentation rate in the gravitation field of the earth].

    Science.gov (United States)

    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.

  13. Determination of alternative pathway of complement activity in mouse serum using rabbit erythrocytes

    NARCIS (Netherlands)

    Dijk, H. van; Rademaker, P.M.; Willers, J.M.N

    1980-01-01

    Rabbit, mouse and sheep erythrocytes expressing different concentrations of membrane sialic acid were used to study possible modes of activation of the alternative complement (C) pathway in mouse, human and guinea pig serum. Mouse erythrocytes activated only human serum, whereas rabbit erythrocytes

  14. An erythrocytic virus of the brazilian tree-frog, Phrynohyas venulosa

    Directory of Open Access Journals (Sweden)

    A. P. Alves de Matos

    1995-10-01

    Full Text Available Blood erythrocytes of Brazilian tree-frogs, Phrynohyas venulosa were found to frequently contain single, small, densely staining inclusions. Electron microscopy showed these to be icosahedral viral particles which measured from 250-280 nm in diameter; they were devoid of an envelope, and thus differed from previously described viruses of frog erythrocytes. The infected erythrocytes lacked a crystalline body.

  15. The involvement of erythrocyte metabolism in organismal homeostasis in health and disease

    NARCIS (Netherlands)

    Bosman, G.J.C.G.M.

    2016-01-01

    Historically, study of erythrocyte homeostasis has focussed on the survival of erythrocytes in the blood bank and, especially in pathological circumstances, on the mechanisms leading to accelerated aging and removal from the circulation. Recent proteomic and metabolomic data suggest that erythrocyte

  16. Experiment study and FEM simulation on erythrocytes under linear stretching of optical micromanipulation

    Science.gov (United States)

    Liu, Ying; Song, Huadong; Zhu, Panpan; Lu, Hao; Tang, Qi

    2017-08-01

    The elasticity of erythrocytes is an important criterion to evaluate the quality of blood. This paper presents a novel research on erythrocytes' elasticity with the application of optical tweezers and the finite element method (FEM) during blood storage. In this work, the erythrocytes with different in vitro times were linearly stretched by trapping force using optical tweezers and the time dependent elasticity of erythrocytes was investigated. The experimental results indicate that the membrane shear moduli of erythrocytes increased with the increasing in vitro time, namely the elasticity was decreasing. Simultaneously, an erythrocyte shell model with two parameters (membrane thickness h and membrane shear modulus H) was built to simulate the linear stretching states of erythrocytes by the FEM, and the simulations conform to the results obtained in the experiment. The evolution process was found that the erythrocytes membrane thicknesses were decreasing. The analysis assumes that the partial proteins and lipid bilayer of erythrocyte membrane were decomposed during the in vitro preservation of blood, which results in thin thickness, weak bending resistance, and losing elasticity of erythrocyte membrane. This study implies that the FEM can be employed to investigate the inward mechanical property changes of erythrocyte in different environments, which also can be a guideline for studying the erythrocyte mechanical state suffered from different diseases.

  17. Erythrocyte ageing in vivo and in vitro: structural aspects and implications for transfusion.

    NARCIS (Netherlands)

    Bosman, G.J.C.G.M.; Werre, J.M.; Willekens, F.L.A.; Novotny, V.M.J.

    2008-01-01

    Erythrocyte transfusion is essential in conditions of large blood loss, of inadequate bone marrow production and of increased erythrocyte breakdown. The structural and biochemical changes that erythrocytes go through during storage, probably associated with the disappearance of up to 30% of the

  18. ABO Blood Groups Influence Macrophage-mediated Phagocytosis of Plasmodium falciparum-infected Erythrocytes

    Science.gov (United States)

    Branch, Donald R.; Hult, Annika K.; Olsson, Martin L.; Liles, W. Conrad; Cserti-Gazdewich, Christine M.; Kain, Kevin C.

    2012-01-01

    Erythrocyte polymorphisms associated with a survival advantage to Plasmodium falciparum infection have undergone positive selection. There is a predominance of blood group O in malaria-endemic regions, and several lines of evidence suggest that ABO blood groups may influence the outcome of P. falciparum infection. Based on the hypothesis that enhanced innate clearance of infected polymorphic erythrocytes is associated with protection from severe malaria, we investigated whether P. falciparum-infected O erythrocytes are more efficiently cleared by macrophages than infected A and B erythrocytes. We show that human macrophages in vitro and mouse monocytes in vivo phagocytose P. falciparum-infected O erythrocytes more avidly than infected A and B erythrocytes and that uptake is associated with increased hemichrome deposition and high molecular weight band 3 aggregates in infected O erythrocytes. Using infected A1, A2, and O erythrocytes, we demonstrate an inverse association of phagocytic capacity with the amount of A antigen on the surface of infected erythrocytes. Finally, we report that enzymatic conversion of B erythrocytes to type as O before infection significantly enhances their uptake by macrophages to observed level comparable to that with infected O wild-type erythrocytes. These data provide the first evidence that ABO blood group antigens influence macrophage clearance of P. falciparum-infected erythrocytes and suggest an additional mechanism by which blood group O may confer resistance to severe malaria. PMID:23071435

  19. Quantum cloning machines and the applications

    Science.gov (United States)

    Fan, Heng; Wang, Yi-Nan; Jing, Li; Yue, Jie-Dong; Shi, Han-Duo; Zhang, Yong-Liang; Mu, Liang-Zhu

    2014-11-01

    No-cloning theorem is fundamental for quantum mechanics and for quantum information science that states an unknown quantum state cannot be cloned perfectly. However, we can try to clone a quantum state approximately with the optimal fidelity, or instead, we can try to clone it perfectly with the largest probability. Thus various quantum cloning machines have been designed for different quantum information protocols. Specifically, quantum cloning machines can be designed to analyze the security of quantum key distribution protocols such as BB84 protocol, six-state protocol, B92 protocol and their generalizations. Some well-known quantum cloning machines include universal quantum cloning machine, phase-covariant cloning machine, the asymmetric quantum cloning machine and the probabilistic quantum cloning machine. In the past years, much progress has been made in studying quantum cloning machines and their applications and implementations, both theoretically and experimentally. In this review, we will give a complete description of those important developments about quantum cloning and some related topics. On the other hand, this review is self-consistent, and in particular, we try to present some detailed formulations so that further study can be taken based on those results.

  20. Quantum cloning machines and the applications

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Heng, E-mail: hfan@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing 100190 (China); Wang, Yi-Nan; Jing, Li [School of Physics, Peking University, Beijing 100871 (China); Yue, Jie-Dong [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Shi, Han-Duo; Zhang, Yong-Liang; Mu, Liang-Zhu [School of Physics, Peking University, Beijing 100871 (China)

    2014-11-20

    No-cloning theorem is fundamental for quantum mechanics and for quantum information science that states an unknown quantum state cannot be cloned perfectly. However, we can try to clone a quantum state approximately with the optimal fidelity, or instead, we can try to clone it perfectly with the largest probability. Thus various quantum cloning machines have been designed for different quantum information protocols. Specifically, quantum cloning machines can be designed to analyze the security of quantum key distribution protocols such as BB84 protocol, six-state protocol, B92 protocol and their generalizations. Some well-known quantum cloning machines include universal quantum cloning machine, phase-covariant cloning machine, the asymmetric quantum cloning machine and the probabilistic quantum cloning machine. In the past years, much progress has been made in studying quantum cloning machines and their applications and implementations, both theoretically and experimentally. In this review, we will give a complete description of those important developments about quantum cloning and some related topics. On the other hand, this review is self-consistent, and in particular, we try to present some detailed formulations so that further study can be taken based on those results.

  1. Gene encoding erythrocyte binding ligand linked to blood stage multiplication rate phenotype in Plasmodium yoelii yoelii.

    Science.gov (United States)

    Pattaradilokrat, Sittiporn; Culleton, Richard L; Cheesman, Sandra J; Carter, Richard

    2009-04-28

    Variation in the multiplication rate of blood stage malaria parasites is often positively correlated with the severity of the disease they cause. The rodent malaria parasite Plasmodium yoelii yoelii has strains with marked differences in multiplication rate and pathogenicity in the blood. We have used genetic analysis by linkage group selection (LGS) to identify genes that determine differences in multiplication rate. Genetic crosses were generated between genetically unrelated, fast- (17XYM) and slowly multiplying (33XC) clones of P. y. yoelii. The uncloned progenies of these crosses were placed under multiplication rate selection in blood infections in mice. The selected progenies were screened for reduction in intensity of quantitative genetic markers of the slowly multiplying parent. A small number of strongly selected markers formed a linkage group on P. y. yoelii chromosome 13. Of these, that most strongly selected marked the gene encoding the P. yoelii erythrocyte binding ligand (pyebl), which has been independently identified by Otsuki and colleagues [Otsuki H, et al. (2009) Proc Natl Acad Sci USA 106:10.1073/pnas.0811313106] as a major determinant of virulence in these parasites. In an analysis of a previous genetic cross in P. y. yoelii, pyebl alleles of fast- and slowly multiplying parents segregated with the fast and slow multiplication rate phenotype in the cloned recombinant progeny, implying the involvement of the pyebl locus in determining the multiplication rate. Our genome-wide LGS analysis also indicated effects of at least 1 other locus on multiplication rate, as did the findings of Otsuki and colleagues on virulence in P. y. yoelii.

  2. Energy Values of Nine Populus Clones

    Science.gov (United States)

    Terry F. Strong

    1980-01-01

    Compares calorific values for components of nine Populus clones. The components include stem wood, stem bark, and branches. Also compares calorific values for clones of balsam poplar and black cottonwood parentages.

  3. Human reproductive cloning: a conflict of liberties.

    Science.gov (United States)

    Havstad, Joyce C

    2010-02-01

    Proponents of human reproductive cloning do not dispute that cloning may lead to violations of clones' right to self-determination, or that these violations could cause psychological harms. But they proceed with their endorsement of human reproductive cloning by dismissing these psychological harms, mainly in two ways. The first tactic is to point out that to commit the genetic fallacy is indeed a mistake; the second is to invoke Parfit's non-identity problem. The argument of this paper is that neither approach succeeds in removing our moral responsibility to consider and to prevent psychological harms to cloned individuals. In fact, the same commitment to personal liberty that generates the right to reproduce by means of cloning also creates the need to limit that right appropriately. Discussion of human reproductive cloning ought to involve a careful and balanced consideration of both the relevant aspects of personal liberty - the parents' right to reproductive freedom and the cloned child's right to self-determination.

  4. Transbilayer movement of various phosphatidylcholine species in intact human erythrocytes

    NARCIS (Netherlands)

    van Meer, G.|info:eu-repo/dai/nl/068570368; op den Kamp, J.A.F.

    1982-01-01

    Phosphatidylcholine specific phospholipid exchange protein was used to introduce (14C)-labeled phosphatidylcholine of different fatty acyl compositions into the intact human erythrocyte. Hydrolysis by a combination of phospholipase A2 and sphingomyelinase was applied to prove that originally all

  5. Dyslipidemia, altered erythrocyte fatty acids and selenium are ...

    African Journals Online (AJOL)

    Dyslipidemia, reduced omega-3 and -6 fatty acids and antioxidative nutrients are modulatory risk factors associated with dementia. Diet, genetics and environment interact with nutritional metabolism and susceptibility to neurodegeneration. This study investigated the relationship between erythrocyte fatty acids and selected ...

  6. Determination of molecular species of lecithin from erythrocytes and plasma

    NARCIS (Netherlands)

    Golde, L.M.G. van; Tomasi, V.; Deenen, L.L.M. van

    The molecular species of lecithin from erythrocyte and plasma of man and rabbit were determined after conversion of the lecithins into diglycerides by means of hydrolysis with phospholipase C. The resultant diglycerides were separated by thin-layer chromatography on silica impregnated with silver

  7. Erythrocyte indices and serum biochemical constituents of broiler ...

    African Journals Online (AJOL)

    One hundred and twenty (120) four weeks old Ross breed broiler finisher birds were used to study the effect of feeding maggot meal as a replacement for fish meal on erythrocyte indices and serum biochemical constituents. The birds were divided into 5 treatment groups identified as T1, T2, T3 , T4 and T5 with 24 birds per ...

  8. Acid Sphingomyelinase Inhibition Prevents Hemolysis During Erythrocyte Storage

    Directory of Open Access Journals (Sweden)

    Richard S. Hoehn

    2016-06-01

    Full Text Available Background/Aims: During storage, units of human red blood cells (pRBCs experience membrane destabilization and hemolysis which may cause harm to transfusion recipients. This study investigates whether inhibition of acid sphingomyelinase could stabilize erythrocyte membranes and prevent hemolysis during storage. Methods: Human and murine pRBCs were stored under standard blood banking conditions with and without the addition of amitriptyline, a known acid sphingomyelinase inhibitor. Hemoglobin was measured with an electronic hematology analyzer and flow cytometry was used to measure erythrocyte size, complexity, phosphatidylserine externalization, and band 3 protein expression. Results: Cell-free hemoglobin, a marker of hemolysis, increased during pRBC storage. Amitriptyline treatment decreased hemolysis in a dose-dependent manner. Standard pRBC storage led to loss of erythrocyte size and membrane complexity, increased phosphatidylserine externalization, and decreased band 3 protein integrity as determined by flow cytometry. Each of these changes was reduced by treatment with amitriptyline. Transfusion of amitriptyline-treated pRBCs resulted in decreased circulating free hemoglobin. Conclusion: Erythrocyte storage is associated with changes in cell size, complexity, membrane molecular composition, and increased hemolysis. Acid sphingomyelinase inhibition reduced these changes in a dose-dependent manner. Our data suggest a novel mechanism to attenuate the harmful effects after transfusion of aged blood products.

  9. Erythrocyte phospholipid and polyunsaturated fatty acid composition in diabetic retinopathy.

    Science.gov (United States)

    Koehrer, Philippe; Saab, Sarah; Berdeaux, Olivier; Isaïco, Rodica; Grégoire, Stéphane; Cabaret, Stéphanie; Bron, Alain M; Creuzot-Garcher, Catherine P; Bretillon, Lionel; Acar, Niyazi

    2014-01-01

    Long chain polyunsaturated fatty acids (LCPUFAs) including docosahexaenoic acid and arachidonic acid are suspected to play a key role in the pathogenesis of diabetes. LCPUFAs are known to be preferentially concentrated in specific phospholipids termed as plasmalogens. This study was aimed to highlight potential changes in the metabolism of phospholipids, and particularly plasmalogens, and LCPUFAs at various stages of diabetic retinopathy in humans. We performed lipidomic analyses on red blood cell membranes from controls and mainly type 2 diabetes mellitus patients with or without retinopathy. The fatty acid composition of erythrocytes was determined by gas chromatography and the phospholipid structure was determined by liquid chromatography equipped with an electrospray ionisation source and coupled with a tandem mass spectrometer (LC-ESI-MS/MS). A significant decrease in levels of docosahexaenoic acid and arachidonic acid in erythrocytes of diabetic patients with or without retinopathy was observed. The origin of this decrease was a loss of phosphatidyl-ethanolamine phospholipids esterified with these LCPUFAs. In diabetic patients without retinopathy, this change was balanced by an increase in the levels of several phosphatidyl-choline species. No influence of diabetes nor of diabetic retinopathy was observed on the concentrations of plasmalogen-type phospholipids. Diabetes and diabetic retinopathy were associated with a reduction of erythrocyte LCPUFAs in phosphatidyl-ethanolamines. The increase of the amounts of phosphatidyl-choline species in erythrocytes of diabetic patients without diabetic retinopathy might be a compensatory mechanism for the loss of LC-PUFA-rich phosphatidyl-ethanolamines.

  10. Erythrocyte phospholipid and polyunsaturated fatty acid composition in diabetic retinopathy.

    Directory of Open Access Journals (Sweden)

    Philippe Koehrer

    Full Text Available Long chain polyunsaturated fatty acids (LCPUFAs including docosahexaenoic acid and arachidonic acid are suspected to play a key role in the pathogenesis of diabetes. LCPUFAs are known to be preferentially concentrated in specific phospholipids termed as plasmalogens. This study was aimed to highlight potential changes in the metabolism of phospholipids, and particularly plasmalogens, and LCPUFAs at various stages of diabetic retinopathy in humans.We performed lipidomic analyses on red blood cell membranes from controls and mainly type 2 diabetes mellitus patients with or without retinopathy. The fatty acid composition of erythrocytes was determined by gas chromatography and the phospholipid structure was determined by liquid chromatography equipped with an electrospray ionisation source and coupled with a tandem mass spectrometer (LC-ESI-MS/MS. A significant decrease in levels of docosahexaenoic acid and arachidonic acid in erythrocytes of diabetic patients with or without retinopathy was observed. The origin of this decrease was a loss of phosphatidyl-ethanolamine phospholipids esterified with these LCPUFAs. In diabetic patients without retinopathy, this change was balanced by an increase in the levels of several phosphatidyl-choline species. No influence of diabetes nor of diabetic retinopathy was observed on the concentrations of plasmalogen-type phospholipids.Diabetes and diabetic retinopathy were associated with a reduction of erythrocyte LCPUFAs in phosphatidyl-ethanolamines. The increase of the amounts of phosphatidyl-choline species in erythrocytes of diabetic patients without diabetic retinopathy might be a compensatory mechanism for the loss of LC-PUFA-rich phosphatidyl-ethanolamines.

  11. In vitro effects of aspirin and paracetamol on human erythrocyte ...

    African Journals Online (AJOL)

    The activity of glutathione-S-transferase of human erythrocytes was monitored spectrophotometically in the presence and absence of two analgesics (aspirin and paracetamol). Five different concentrations (1.0, 3.0, 5.0, 7.0, 9.0 and 10.0 mg/ml) of each analgesic were used which covers the reported therapeutic and toxic ...

  12. influence of pregnancy on some erythrocyte biochemical profiles in ...

    African Journals Online (AJOL)

    Femi Olaleye

    of Na2EDTA-2-mercaptoethanol. Preparation of lysate for some clinical chemical parameters assays. The haemolysate was prepared as described by Wilson and Dixon (1991). The erythrocyte count of the lithium chloride-washed cells was determined as described by. Jam (1986), after thorough mixing, 108 red blood cells.

  13. Erratum Detergent-resistant membranes in human erythrocytes and ...

    Indian Academy of Sciences (India)

    Unknown

    Figure 3. Immunodetection of flotillin-2 and band 3 in DRMs isolated from erythrocyte ghosts by various treatments. Flotillin-2. (left) and band 3 (right) Western blotting in ten fractions of 0⋅5 ml each, obtained from the sucrose gradients described in figure 2 and numbered from top to bottom. Flotillin-2 is enriched in DRMs ...

  14. Role of aminotransferases in glutamate metabolism of human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ellinger, James J. [University of Wisconsin-Madison, Department of Biochemistry (United States); Lewis, Ian A. [Princeton University, Lewis-Sigler Institute for Integrative Genomics (United States); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, Department of Biochemistry (United States)

    2011-04-15

    Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from {alpha}-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional {sup 1}H-{sup 13}C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

  15. Erythrocyte osmotic fragility of pigs administered ascorbic acid and ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-01-11

    Jan 11, 2010 ... The experiment was carried out with the aim of investigating the effect of an antioxidant ascorbic acid on erythrocyte osmotic fragility of pigs transported by road for 4 h during the harmattan season. 16 pigs administered with ascorbic acid at the dose of 250 mg/kg per os and individually served as.

  16. Influence of haemoglobin solution from sickled erythrocytes on ...

    African Journals Online (AJOL)

    There are conflicting reports concerning vascular reactivity changes in sickle cell anaemia (SCA). The goal of the present study was to examine possible interactions between components of sickle erythrocytes and the vascular endothelium, that may alter vascular reactivity in isolated rabbit carotid arteries.

  17. Erythrocyte indices of iron status in children with cyanotic congenital ...

    African Journals Online (AJOL)

    Background Iron (Fe) deficiency is a known feature of cyanotic congenital heart disease (CCHD) and may worsen symptoms. The prevalence of iron deficiency among children with CCHD at the University College Hospital (UCH), Ibadan is unknown. Erythrocyte indices of iron status are easier and less expensive to ...

  18. Erythrocyte Sodium Sensitivity and Eryptosis in Chronic Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Anna Meyring-Wösten

    2017-06-01

    Full Text Available Background/Aims: In hemodialysis (HD patients the endothelial and erythrocyte glycocalyx is impaired which in turn correlates with elevated erythrocyte sodium sensitivity (ESS. Additionally, apoptotic erythrocyte death (eryptosis, characterized by phosphatidylserine (PS exposure on the cell surface, is increased in this population. We aimed to explore the relationship of ESS and eryptosis. Methods: Blood samples were collected from 11 healthy controls and 20 chronic HD patients before and after midweek HD. ESS was quantified by the salt blood test. PS-exposure, intracellular reactive oxygen species (ROS of erythrocytes and reticulocytes were assessed by flow cytometry. Results: Compared to controls ESS was significantly higher in HD patients preHD and did not change during treatment. The percentage of eryptotic cells did not differ between controls and patients preHD. However, eryptosis decreased during HD. ESS and eryptosis were uncorrelated, while eryptosis was positively correlated with intracellular ROS and percent reticulocytes. Conclusions: Higher ESS levels in HD patients indicate a pathologic glycocalyx. ESS and eryptosis were not correlated. The decreased eryptosis postHD may possibly be related to dialytic uremic toxin removal, but is likely multifactorial. The relationship between eryptosis and intracellular ROS warrants further research.

  19. Effect of garlic's mode of administration on erythrocytes and plasma ...

    African Journals Online (AJOL)

    Garlic preparations are recognized as hypolipidemic, cardioprotective and antihypertensive agents. However, there are some discrepancies about the beneficial effects of garlic according to dosage and mode of administration. We aimed to determine the ability of high dosage garlic (5 g/kg bw) to modulate erythrocytes and ...

  20. Improved Erythrocyte Osmotic Fragility and Packed Cell Volume ...

    African Journals Online (AJOL)

    Improved Erythrocyte Osmotic Fragility and Packed Cell Volume following administration of Aloe barbadensis Juice Extract in Rats. ... Abstract. Aloe barbadensis is a popular house plant that has a long history of a multipurpose folk remedy. ... Keywords: osmotic fragility, packed cell volume, haemoglobin, Aloe vera ...

  1. Mercury chloride-induced oxidative stress in human erythrocytes ...

    African Journals Online (AJOL)

    ONOS

    2010-01-25

    Jan 25, 2010 ... Key words: Mercury chloride, vitamins C and E, oxidative stress, erythrocytes, in vitro. ... of free radicals induced by oxidative damage to lipids and lipoproteins in various cellular ... metals toxicity in different experimental systems ..... vitamins C, E and beta carotene aganist gamma-ray-induced DNA damage ...

  2. A comparative analysis of kinetic models of erythrocyte glycolysis.

    NARCIS (Netherlands)

    du Preez, F.B.; Conradie, R.; Penkler, G.P.; Holm, K.; van dooren, F.L.J.; Snoep, J.L.

    2008-01-01

    Since the 1970s, with Heinrich as a pioneer in the field, numerous kinetic models of erythrocyte glycolysis have been constructed. A functional comparison of eight of these models indicates that the production of ATP and GSH in the red blood cell is largely controlled by the demand reactions. The

  3. Erythrocyte Antioxidant Protection of Rose Hips (Rosa spp.

    Directory of Open Access Journals (Sweden)

    C. Widén

    2012-01-01

    Full Text Available 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 C18 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.

  4. Changes in erythrocytic deformability and plasma viscosity in neonatal ictericia.

    Science.gov (United States)

    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 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 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.

  5. Investigation of the peripheral erythrocytes of Cyprinus carpio

    African Journals Online (AJOL)

    Clastogenic effects of home wastes and agricultural contaminates of Lake Uluabat ("40°11'41.38"N, "28°27'08.40"E) were investigated in peripheral erythrocytes of Cyprinus carpio. Examination of blood smears showed that the formation of micronuclei was significantly increased (f = 21.89, df = 3) with p value > 0.001during ...

  6. Modulatory Role of Antioxidant Vitamins C and E on Erythrocyte ...

    African Journals Online (AJOL)

    Vitamin C and E supplements were administered to sodium nitrate-treated rats in order to examine the possible ameliorative effects of these antioxidants on erythrocyte osmotic fragility. Seventy adult Wistar rats were randomly divided into seven groups (n=10) and administered drugs or distilled water orally using a metallic ...

  7. Detergent-resistant membranes in human erythrocytes and their ...

    Indian Academy of Sciences (India)

    Unknown

    Introduction. Lipid microdomains enriched in cholesterol and sphin- golipids are thought to exist in vivo in the membranes of living cells (Edidin 1997, 2001; Brown and London. 1998; Pike 2004). These structures are sites of ...... induced in erythrocytes infected by malaria parasites; Cell. Microbiol. 4 383–395. Heerklotz H ...

  8. Lipid Peroxidation And Erythrocyte Fragility In Poorly Controlled ...

    African Journals Online (AJOL)

    Thus there is increased interest in determining the oxidative status of persons with diabetes. Objectives: This study was carried out to determine if the plasma oxidative stress status is high in diabetics (especially those that are poorly controlled) and to determine the effect on erythrocyte stability. Methods: Plasma levels of ...

  9. Procalcitonin and white blood cell count (WBC), erythrocyte ...

    African Journals Online (AJOL)

    The present prospective observational study aimed to determine the correlation between procalcitonin (PCT) and white blood cell count (WBC), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in toddlers before and after treatment. Moreover, 50 patients aged 1 to 36 months who were hospitalized at the ...

  10. In vitro Erythrocyte Haemolysis Inhibition Properties of Senna ...

    African Journals Online (AJOL)

    The objective of this work was to study the antioxidant properties, of this plant using an erythrocyte haemolysis inhibition assay, because one way to justify the traditional anticancer uses can be through the concept of antioxidant effect. Crude extracts from leaves and bark of S. singueana were prepared by maceration with ...

  11. Erythrocytes for Drug Delivery and their Applications: A Review ...

    African Journals Online (AJOL)

    Recent advances have witnessed the emergence of an increasing number of novel carriers for the delivery of drugs. In this manuscript, we review and discuss the blood cellular carriers because of their great biocompatibility and thus a reduction in side effects. Our emphasis was on the erythrocyte because recent studies ...

  12. Clinical utility of the erythrocyte sedimentation rate test and ...

    African Journals Online (AJOL)

    Background: The erythrocyte sedimentation rate (ESR) is a relatively non-specific test that is often ignored during the diagnosis and monitoring of disease. However, in recent times, the test is often requested alongside haemoglobin electrophoretic pattern as pre marital test. This study was aimed at determining the ESR ...

  13. Erythrocyte osmotic fragility of pigs administered ascorbic acid and ...

    African Journals Online (AJOL)

    The experiment was carried out with the aim of investigating the effect of an antioxidant ascorbic acid on erythrocyte osmotic fragility of pigs transported by road for 4 h during the harmattan season. 16 pigs administered with ascorbic acid at the dose of 250 mg/kg per os and individually served as experimental animals and ...

  14. Influence of pregnancy on some erythrocyte biochemical profiles in ...

    African Journals Online (AJOL)

    One billion erythrocytes lysate samples obtained from pregnant (28-day old) and non-pregnant groups or New Zealand white Chinchilla rabbits (eight rabbits per group) were analysed to determine the influence of pregnancy on the profile of some of the intracellular electrolytes, enzymes, lipids, proteins and rnetabolites.

  15. Associations of erythrocyte fatty acid patterns with insulin resistance

    Science.gov (United States)

    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...

  16. Erythrocyte membrane fatty acids in multiple sclerosis patients and ...

    African Journals Online (AJOL)

    The risk of developing multiple sclerosis (MS) is associated with increased dietary intake of saturated fatty acids. For many years it has been suspected that this disease might be associated with an imbalance between unsaturated and saturated fatty acids. We determined erythrocyte membrane fatty acids levels in Hot ...

  17. Effective and efficient model clone detection

    DEFF Research Database (Denmark)

    Störrle, Harald

    2015-01-01

    automatically (“MDD-style”) or hand-crafted following the blueprint defined by the model (“MBSD-style”). Unfortunately, however, model clones are much less well studied than code clones. In this paper, we present a clone detection algorithm for UML domain models. Our approach covers a much greater variety...

  18. Interaction of selected anthocyanins with erythrocytes and liposome membranes.

    Science.gov (United States)

    Bonarska-Kujawa, Dorota; Pruchnik, Hanna; Kleszczyńska, Halina

    2012-06-01

    Anthocyanins are one of the main flavonoid groups. They are responsible for, e.g., the color of plants and have antioxidant features and a wide spectrum of medical activity. The subject of the study was the following compounds that belong to the anthocyanins and which can be found, e.g., in strawberries and chokeberries: callistephin chloride (pelargonidin-3-O-glucoside chloride) and ideain chloride (cyanidin-3-O-galactoside chloride). The aim of the study was to determine the compounds' antioxidant activity towards the erythrocyte membrane and changes incurred by the tested anthocyanins in the lipid phase of the erythrocyte membrane, in liposomes composed of erythrocyte lipids and in DPPC, DPPC/cholesterol and egg lecithin liposomes. In particular, we studied the effect of the two selected anthocyanins on red blood cell morphology, on packing order in the lipid hydrophilic phase, on fluidity of the hydrophobic phase, as well as on the temperature of phase transition in DPPC and DPPC/cholesterol liposomes. Fluorimetry with the Laurdan and Prodan probes indicated increased packing density in the hydrophilic phase of the membrane in the presence of anthocyanins. Using the fluorescence probes DPH and TMA-DPH, no effect was noted inside the hydrophobic phase of the membrane, as the lipid bilayer fluidity was not modified. The compounds slightly lowered the phase transition temperature of phosphatidylcholine liposomes. The study has shown that both anthocyanins are incorporated into the outer region of the erythrocyte membrane, affecting its shape and lipid packing order, which is reflected in the increasing number of echinocytes. The investigation proved that the compounds penetrate only the outer part of the external lipid layer of liposomes composed of erythrocyte lipids, DPPC, DPPC/cholesterol and egg lecithin lipids, changing its packing order. Fluorimetry studies with DPH-PA proved that the tested anthocyanins are very effective antioxidants. The antioxidant

  19. Stimulation of Suicidal Erythrocyte Death by Phosphatase Inhibitor Calyculin A

    Directory of Open Access Journals (Sweden)

    Mustafa Almasry

    2016-11-01

    Full Text Available Background/Aims: The serine/threonine protein phosphatase 1 and 2a inhibitor Calyculin A may trigger suicidal death or apoptosis of tumor cells. Similar to apoptosis of nucleated cells, erythrocytes may enter eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+] i. Eryptosis is fostered by activation of staurosporine sensitive protein kinase C, SB203580 sensitive p38 kinase, and D4476 sensitive casein kinase. Eryptosis may further involve zVAD sensitive caspases. The present study explored, whether Calyculin A induces eryptosis and, if so, whether its effect requires Ca2+ entry, kinases and/or caspases Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, and [Ca2+] i from Fluo-3 fluorescence, as determined by flow cytometry. Results: A 48 hours exposure of human erythrocytes to Calyculin A (≥ 2.5 nM significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter and significantly increased Fluo-3 fluorescence. The effect of Calyculin A on annexin-V-binding was significantly blunted by removal of extracellular Ca2+, by staurosorine (1 µM, SB203580 (2 µM, D4476 (10 µM, and zVAD (10 µM. Conclusions: Calyculin A triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part requiring Ca2+ entry, kinase activity and caspase activation.

  20. Blood erythrocyte and hemoglobin concentrations in premature adrenarche.

    Science.gov (United States)

    Utriainen, Pauliina; Jääskeläinen, Jarmo; Voutilainen, Raimo

    2013-01-01

    Premature adrenarche (PA) is characterized by an earlier than normal increase in adrenocortical androgen production, and it is associated with increased serum IGF-I concentrations. Both the GH-IGF system and androgens, particularly testosterone, are known to enhance erythropoiesis. Our objective was to test the hypothesis that blood erythrocyte count and blood hemoglobin (B-Hb) concentration are increased in PA. Sixty-four prepubertal children (10 boys) with clinically and biochemically defined PA and 62 healthy prepubertal controls (10 boys) participating in our Premature Adrenarche study were examined, and a fasting blood sample was drawn at a university hospital. We evaluated B-Hb and erythrocyte, thrombocyte, and leukocyte counts and their association with serum dehydroepiandrosterone sulfate (DHEAS), testosterone and IGF-I concentrations. Children with PA had higher mean blood erythrocyte count (4.74 vs. 4.64 × 10(12)/liter, P = 0.04; significant difference in girls but not in boys) and a tendency toward higher B-Hb (130 vs. 128 g/liter, P = 0.06) than their controls. No difference was observed in leukocyte or thrombocyte counts between the study groups. In linear regression models including age, sex, body mass index SD score, IGF-I, and DHEAS or testosterone, B-Hb was associated with serum DHEAS (P = 0.04), testosterone (P = 0.01), and IGF-I (P ≤ 0.003) concentrations in the entire study cohort and with IGF-I separately in girls (P ≤ 0.02). Similar models showed a significant association of blood erythrocyte count with serum IGF-I concentration (P = 0.003-0.049) but not with DHEAS or testosterone. Increased erythrocyte count in PA girls suggests that relatively small increases in serum androgen or IGF-I concentrations during adrenarche may associate with enhanced erythropoiesis.

  1. Red wine activates plasma membrane redox system in human erythrocytes.

    Science.gov (United States)

    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.

  2. A single-copy galK promoter cloning vector suitable for cloning strong promoters

    DEFF Research Database (Denmark)

    Dandanell, Gert; Court, Donald L.; Hammer, Karin

    1986-01-01

    We report the construction of lambda galK promoter cloning vectors for cloning and characterization of strong promoters. This phage, which contains a unique HindIII cloning site, was applied to the cloning and analysis of transcription initiations of the regulatory region of the deo-operon of...

  3. [Effect of congrong powder preparation on erythrocyte parameter and index of blood rheology in rats].

    Science.gov (United States)

    Liu, Zhengran; Zhang, Dong; Wu, Haijun; Li, Yueling; Chen, Shiping; Yang, Yumei

    2010-11-01

    To observe the effect of Congrong powder preparation on erythrocyte parameter and the index of blood rheology in healthy rats. The 50 rats were randomly divided into 5 groups ( physiological saline group, testosterone propionate group, large-dose administered group, moderate-dose administered group, small-dose administered group). Blood were taken to determine erythrocyte parameter and the index of blood rheology. Congrong powder preparation had no effect on erythrocyte parameter. There was an increase in whole blood viscosity, whole blood reduction viscosity, and in the erythrocyte rigidity index in the large-dose administered group. Congrong powder can influence deformability and some related characters of erythrocytes.

  4. Enhanced bilirubin binding to different mammalian erythrocytes in the presence of magnesium ions

    OpenAIRE

    Ali, M. K.; Siddiqui, M.U; Tayyab, S.

    2001-01-01

    Effect of magnesium ions on the binding of bilirubin to erythrocytes of different mammalian species, namely, human, buffalo, goat and sheep was studied. Increase in the concentration of magnesium ions led to a gradual increase in the erythrocyte-bound bilirubin in both human and buffalo erythrocytes whereas in sheep and goat erythrocytes, the pronounced increase was found beyond 2.0 and 2.7 mM MgCl2 concentrations respectively. Percentage increase in erythrocyte-bound bilirubin was found high...

  5. Determination of glucose metabolites in stored erythrocytes and in erythrocytes from patients with thalassemia by analytical isotachophoresis.

    Science.gov (United States)

    Kuçi, Zyrafete; Hins, Jürgen; Kuçi, Selim; Renner, Susanne; Flottmann, Dirk; Bruchelt, Gernot

    2006-11-30

    Glycolysis is for some cells, such as erythrocytes, neutrophil granulocytes and many cancer cells, the only or most important source of energy (ATP) production. Based on previous studies we developed an isotachophoretic (ITP) method which allows, in principle, the simultaneous determination of all metabolites of glycolysis. Since glucose metabolites are small anions, mobility of some of them may overlap in isotachophoresis and, therefore, partial mixed zones are generated. By variation of the leading/terminating system, however, it is possible to separate the compounds of interest. In this communication, we describe a method for analysis of glucose metabolites in erythrocytes from healthy donors during storage in blood bags, and from patients with thalassemia, with special respect to intracellular 2,3 bisphosphoglycerate, lactate and ATP/ADP. The well known characteristic changes of glycolysis in erythrocytes during blood storage and in erythrocytes from thalassemia patients, which are often analysed by separate enzymatic assays, could be confirmed with this isotachophoretic procedure. The method is currently adapted for analysis of glycolysis in neutrophil granulocytes and cancer cells which requires some modifications of sample preparation and performance of the isotachophoretic analysis.

  6. Acute dark chocolate ingestion is beneficial for hemodynamics via enhancement of erythrocyte deformability in healthy humans.

    Science.gov (United States)

    Radosinska, Jana; Horvathova, Martina; Frimmel, Karel; Muchova, Jana; Vidosovicova, Maria; Vazan, Rastislav; Bernatova, Iveta

    2017-03-01

    Erythrocyte deformability is an important property of erythrocytes that considerably affects blood flow and hemodynamics. The high content of polyphenols present in dark chocolate has been reported to play a protective role in functionality of erythrocytes. We hypothesized that chocolate might influence erythrocytes not only after repeated chronic intake, but also immediately after its ingestion. Thus, we determined the acute effect of dark chocolate and milk (with lower content of biologically active substances) chocolate intake on erythrocyte deformability. We also focused on selected factors that may affect erythrocyte deformability, specifically nitric oxide production in erythrocytes and total antioxidant capacity of plasma. We determined posttreatment changes in the mentioned parameters 2hours after consumption of chocolate compared with their levels before consumption of chocolate. In contrast to milk chocolate intake, the dark chocolate led to a significantly higher increase in erythrocyte deformability. Nitric oxide production in erythrocytes was not changed after dark chocolate intake, but significantly decreased after milk chocolate. The plasma total antioxidant capacity remained unaffected after ingestion of both chocolates. We conclude that our hypothesis was confirmed. Single ingestion of dark chocolate improved erythrocyte deformability despite unchanged nitric oxide production and antioxidant capacity of plasma. Increased deformability of erythrocytes may considerably improve rheological properties of blood and thus hemodynamics in humans, resulting in better tissue oxygenation. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Attempts to validate a possible predictive animal model for human erythrocyte G-6-PD deficiency

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Flow cytometric determination of osmotic behaviour of animal erythrocytes toward their engineering for drug delivery

    Directory of Open Access Journals (Sweden)

    Kostić Ivana T.

    2015-01-01

    Full Text Available Despite the fact that the methods based on the osmotic properties of the cells are the most widely used for loading of drugs in human and animal erythrocytes, data related to the osmotic properties of erythrocytes derived from animal blood are scarce. This work was performed with an aim to investigate the possibility of use the flow cytometry as a tool for determination the osmotic behaviour of porcine and bovine erythrocytes, and thus facilitate the engineering of erythrocytes from animal blood to be drug carriers. The method of flow cytometry successfully provided the information about bovine and porcine erythrocyte osmotic fragility, and made the initial steps in assessment of erythrocyte shape in a large number of erythrocytes. Although this method is not able to confirm the swelling of pig erythrocytes, it indicated to the differences in pig erythrocytes that had basic hematological parameters inside and outside the reference values. In order to apply/use the porcine and bovine erythrocytes as drug carriers, the method of flow cytometry, confirming the presence of osmotically different fractions of red blood cells, indicated that various amounts of the encapsulated drug in porcine and bovine erythrocytes can be expected.

  9. Biological characterization of clones derived from the edmonston strain of measles virus in comparison with schwarz and CAM-70 vaccine strains

    Directory of Open Access Journals (Sweden)

    Maria Beatriz Junqueira Borges

    1996-08-01

    Full Text Available Four virus clones were derived from the Edmonston strain of measles virus by repeated plaque purification. These clones were compared with the vaccine strains Schwarz and CAM-70 in terms of biological activities including plaque formation, hemagglutination, hemolysis and replication in Vero cells and chick embryo fibroblasts (CEF. Two clones of intermediate plaque yielded mixed plaque populations on subcultivation whereas the other two, showing small and large plaque sizes, showed stable plaque phenotypes. The vaccine strains showed consistent homogeneous plaque populations. All the Edmonston clones showed agglutination of monkey erythrocytes in isotonic solution while both vaccine strains hemagglutinated only in the presence of high salt concentrations. Variation in the hemolytic activity was observed among the four clones but no hemolytic activity was detected for the vaccine virus strains. Vaccine strains replicated efficiently both in Vero cells and CEF. All four clones showed efficient replication in Vero cells but different replication profiles in CEF. Two of them replicated efficiently, one was of intermediate efficiency and the other showed no replication in CEF. Two of the clones showed characteristics similar to vaccine strains. One in terms of size and homogeneity of plaques, the other for a low hemolytic activity and both for the efficiency of propagation in CEF.

  10. El envejecimiento de los clones

    OpenAIRE

    Trippi, Victorio S.

    2007-01-01

    El envejecimiento de los clones se observa en plantas que muestran crecimiento definido por un determinismo genético, cuando se multiplican con tejidos que evolucionan hacia el crecimiento reproductivo. Las plantas fuertemente influenciadas por el ambiente, pueden mostrar fenómenos de senescencia cuando la condición de ambiente determina el crecimiento reproductivo. Los cambios asociados con la edad resultan de alteraciones del citoplasma como un tipo de diferenciación cel...

  11. Identification and characterization of human SLP-2, a novel homologue of stomatin (band 7.2b) present in erythrocytes and other tissues.

    Science.gov (United States)

    Wang, Y; Morrow, J S

    2000-03-17

    Human stomatin (band 7.2b) is a 31-kDa erythrocyte membrane protein of unknown function but implicated in the control of ion channel permeability, mechanoreception, and lipid domain organization. Although absent in erythrocytes from patients with hereditary stomatocytosis, stomatin is not linked to this disorder. A second stomatin homologue, termed SLP-1, has been identified in nonerythroid tissues, and other stomatin related proteins are found in Drosophila, Caenorhabditis elegans, and plants. We now report the cloning and characterization of a new and unusual stomatin homologue, human SLP-2 (stomatin-like protein 2). SLP-2 is encoded by an approximately 1.5-kilobase mRNA (GenBank(TM) accession no. AF190167). The gene for human SLP-2, HUSLP2, is present on chromosome 9p13. Its derived amino acid sequence predicts a 38,537-kDa protein that is overall approximately 20% similar to human stomatin. Northern and Western blots for SLP-1 and SLP-2 reveal a wide but incompletely overlapping tissue distribution. Unlike SLP-1, SLP-2 is also present in mature human erythrocytes ( approximately 4,000 +/- 5,600 (+/- 2 S.D.) copies/cell). SLP-2 lacks a characteristic NH(2)-terminal hydrophobic domain found in other stomatin homologues and (unlike stomatin) is fully extractable from erythrocyte membranes by NaOH, pH 11. SLP-2 partitions into both Triton X-100-soluble and -insoluble pools in erythrocyte ghost membranes or when expressed in cultured COS cells and migrates anomalously on SDS-polyacrylamide gel electrophoresis analysis with apparent mobilities of approximately 45,500, 44,600, and 34,300 M(r). The smallest of these protein bands is believed to represent the product of alternative translation initiated at AUGs beginning with nt 217 or 391, although this point has not been rigorously proven. Collectively, these findings identify a novel and unusual member of the stomatin gene superfamily that interacts with the peripheral erythrocyte cytoskeleton and presumably other

  12. Therapeutic and reproductive cloning: a critique.

    Science.gov (United States)

    Bowring, Finn

    2004-01-01

    This article is a critical examination of the science and ethics of human cloning. It summarises the key scientific milestones in the development of nuclear transplantation, explains the importance of cloning to research into the medical potential of embryonic stem cells, and discusses the well-worn distinction between 'therapeutic' and 'reproductive' cloning. Suggesting that this distinction will be impossible to police, it goes on to consider the ethics of full human cloning. It is concluded that it represents an unacceptable form of parental despotism, and that the genetic engineering and cloning of future human beings will fracture the foundations of modern humanism.

  13. Production of gene-corrected adult beta globin protein in human erythrocytes differentiated from patient iPSCs after genome editing of the sickle point mutation

    Science.gov (United States)

    Huang, Xiaosong; Wang, Ying; Yan, Wei; Smith, Cory; Ye, Zhaohui; Wang, Jing; Gao, Yongxing; Mendelsohn, Laurel; Cheng, Linzhao

    2015-01-01

    Summary Human induced pluripotent stem cells (iPSCs) and genome editing provide a precise way to generate gene-corrected cells for disease modeling and cell therapies. Human iPSCs generated from sickle cell disease (SCD) patients have a homozygous missense point mutation in the HBB gene encoding adult β-globin proteins, and are used as a model system to improve strategies of human gene therapy. We demonstrate that the CRISPR/Cas9 system designer nuclease is much more efficient in stimulating gene targeting of the endogenous HBB locus near the SCD point mutation in human iPSCs than ZFNs and TALENs. Using a specific guide RNA and Cas9, we readily corrected one allele of the SCD HBB gene in human iPSCs by homologous recombination with a donor DNA template containing the wild-type HBB DNA and a selection cassette that was subsequently removed to avoid possible interference of HBB transcription and translation. We chose targeted iPSC clones that have one corrected and one disrupted SCD allele for erythroid differentiation assays, using an improved xeno-free and feeder-free culture condition we recently established. Erythrocytes from either the corrected or its parental (uncorrected) iPSC line were generated with similar efficiencies. Currently ~6%-10% of these differentiated erythrocytes indeed lacked nuclei, characteristic of further matured erythrocytes called reticulocytes. We also detected the 16-kD β-globin protein expressed from the corrected HBB allele in the erythrocytes differentiated from genome-edited iPSCs. Our results represent a significant step towards the clinical applications of genome editing using patient-derived iPSCs to generate disease-free cells for cell and gene therapies. PMID:25702619

  14. Cloning expeditions: risky but rewarding.

    Science.gov (United States)

    Lodish, Harvey

    2013-12-01

    In the 1980s, a good part of my laboratory was using the then-new recombinant DNA techniques to clone and characterize many important cell surface membrane proteins: GLUT1 (the red cell glucose transporter) and then GLUT2 and GLUT4, the red cell anion exchange protein (Band 3), asialoglycoprotein receptor subunits, sucrase-isomaltase, the erythropoietin receptor, and two of the subunits of the transforming growth factor β (TGF-β) receptor. These cloned genes opened many new fields of basic research, including membrane insertion and trafficking of transmembrane proteins, signal transduction by many members of the cytokine and TGF-β families of receptors, and the cellular physiology of glucose and anion transport. They also led to many insights into the molecular biology of several cancers, hematopoietic disorders, and diabetes. This work was done by an exceptional group of postdocs and students who took exceptionally large risks in developing and using novel cloning technologies. Unsurprisingly, all have gone on to become leaders in the fields of molecular cell biology and molecular medicine.

  15. Cloning Expeditions: Risky but Rewarding

    Science.gov (United States)

    2013-01-01

    In the 1980s, a good part of my laboratory was using the then-new recombinant DNA techniques to clone and characterize many important cell surface membrane proteins: GLUT1 (the red cell glucose transporter) and then GLUT2 and GLUT4, the red cell anion exchange protein (Band 3), asialoglycoprotein receptor subunits, sucrase-isomaltase, the erythropoietin receptor, and two of the subunits of the transforming growth factor β (TGF-β) receptor. These cloned genes opened many new fields of basic research, including membrane insertion and trafficking of transmembrane proteins, signal transduction by many members of the cytokine and TGF-β families of receptors, and the cellular physiology of glucose and anion transport. They also led to many insights into the molecular biology of several cancers, hematopoietic disorders, and diabetes. This work was done by an exceptional group of postdocs and students who took exceptionally large risks in developing and using novel cloning technologies. Unsurprisingly, all have gone on to become leaders in the fields of molecular cell biology and molecular medicine. PMID:24061478

  16. Genetic Evidence for Erythrocyte Receptor Glycophorin B Expression Levels Defining a Dominant Plasmodium falciparum Invasion Pathway into Human Erythrocytes

    Science.gov (United States)

    Dankwa, Selasi; Chaand, Mudit; Kanjee, Usheer; Jiang, Rays H. Y.; Nobre, Luis V.; Goldberg, Jonathan M.; Bei, Amy K.; Moechtar, Mischka A.; Grüring, Christof; Ahouidi, Ambroise D.; Ndiaye, Daouda; Dieye, Tandakha N.; Mboup, Souleymane; Weekes, Michael P.

    2017-01-01

    ABSTRACT Plasmodium falciparum, the parasite that causes the deadliest form of malaria, has evolved multiple proteins known as invasion ligands that bind to specific erythrocyte receptors to facilitate invasion of human erythrocytes. The EBA-175/glycophorin A (GPA) and Rh5/basigin ligand-receptor interactions, referred to as invasion pathways, have been the subject of intense study. In this study, we focused on the less-characterized sialic acid-containing receptors glycophorin B (GPB) and glycophorin C (GPC). Through bioinformatic analysis, we identified extensive variation in glycophorin B (GYPB) transcript levels in individuals from Benin, suggesting selection from malaria pressure. To elucidate the importance of the GPB and GPC receptors relative to the well-described EBA-175/GPA invasion pathway, we used an ex vivo erythrocyte culture system to decrease expression of GPA, GPB, or GPC via lentiviral short hairpin RNA transduction of erythroid progenitor cells, with global surface proteomic profiling. We assessed the efficiency of parasite invasion into knockdown cells using a panel of wild-type P. falciparum laboratory strains and invasion ligand knockout lines, as well as P. falciparum Senegalese clinical isolates and a short-term-culture-adapted strain. For this, we optimized an invasion assay suitable for use with small numbers of erythrocytes. We found that all laboratory strains and the majority of field strains tested were dependent on GPB expression level for invasion. The collective data suggest that the GPA and GPB receptors are of greater importance than the GPC receptor, supporting a hierarchy of erythrocyte receptor usage in P. falciparum. PMID:28760933

  17. Segregation into separate rouleaux of erythrocytes from different species. Evidence against the agglomerin hypothesis of rouleaux formation.

    OpenAIRE

    Forsdyke, D R; Ford, P. M.

    1983-01-01

    Erythrocytes from one species were labelled with fluorescein isothiocyanate and mixed with unlabelled erythrocytes from another species. Albumin polymers were added to generate rouleaux. The species of origin of erythrocytes in rouleaux was determined by fluorescence microscopy. Erythrocytes from different species segregated into independent rouleaux. However, fluorescent and non-fluorescent erythrocytes from one individual were mixed randomly in rouleaux. These results confirm, using a novel...

  18. [Nonspecific effect of morphine on the erythrocyte membrane].

    Science.gov (United States)

    Kuznetsov, P E; Zlobin, V A; Nazarov, G V; Kuznetsova, N B; Rogacheva, S M; Gracheva, A A

    2004-01-01

    The effect of low morphine concentrations on the plasmatic membranes of erythrocytes without opiate receptors was investigated. It was shown that the ATPase activity and hemolytic stability of erythrocytes, which characterize the state of cell membranes and the mobility of the near-membrane water phase, depend on the concentration of morphine, and this dependence is wave-like. The nonmonotonous dependence of the biological response was suggested to be due to changes in the structure of water hydrogen links near the membrane surface, induced by opiate molecules. The hypothesis was confirmed by the results of studies of morphine water solutions using the methods of fluorescent probe and light scattering. It was found that the intensity of light scattering by water and the mobility of its molecules considerably increase in the presence of strictly specified concentrations of morphine.

  19. Quantitative evaluation of respiration induced metabolic oscillations in erythrocytes

    DEFF Research Database (Denmark)

    Hald, Bjørn; Madsen, Mads F; Danø, Sune

    2009-01-01

    solely by steady state consideration. The metabolic system exhibits a broad distribution of time scales. Relaxations of modes with hemoglobin and Mg(2+) binding reactions are very fast, while modes involving glycolytic, membrane transport and 2,3-BPG shunt reactions are much slower. Incomplete slow mode......The changes in the partial pressures of oxygen and carbon dioxide (P(O(2)) and P(CO(2))) during blood circulation alter erythrocyte metabolism, hereby causing flux changes between oxygenated and deoxygenated blood. In the study we have modeled this effect by extending the comprehensive kinetic...... model by Mulquiney and Kuchel [P.J. Mulquiney, and P.W. Kuchel. Model of 2,3-bisphosphoglycerate metabolism in the human erythrocyte based on detailed enzyme kinetic equations: equations and parameter refinement, Biochem. J. 1999, 342, 581-596.] with a kinetic model of hemoglobin oxy...

  20. Sickle discocytes form more rouleaux in vitro than normal erythrocytes.

    Science.gov (United States)

    Obiefuna, P C; Photiades, D P

    1990-06-01

    Rouleaux formation of washed erythrocytes was studied in 32 normal (HbAA) individuals and 30 sickle cell anaemia (HbSS) patients. Washed red cells were suspended in their plasma and rouleaux formation visualized with the aid of an inverted microscope connected to a video camera-monitor unit. Aggregation rate was studied by visual particle counting. Washed sickle discocytes showed rouleaux formation three times as high as normal cells. Red cells were also suspended in buffered Ringer solution containing dextran (a rouleaux inducer). Again, washed erythrocytes from sicklers were about 3 times more aggregable than normal cells at all pH values studied. Increased acidity appeared to aggravate rouleaux formation in both Hb genotypes. We also found plasma fibrinogen concentration in sicklers to be about twice as high as that of normals. High rouleaux formation in sicklers could be attributed not only to fibrinogen and other plasma factors but also to cellular factors.

  1. Human erythrocytes as nanoparticle carriers for magnetic particle imaging

    Energy Technology Data Exchange (ETDEWEB)

    Markov, D E; Boeve, H [Philips Research Europe, High Tech Campus 4, 5656 AE Eindhoven (Netherlands); Gleich, B; Borgert, J [Philips Research Europe, Sector Medical Imaging Systems, Roentgenstrasse 24-26, 22335 Hamburg (Germany); Antonelli, A; Sfara, C; Magnani, M, E-mail: hans.boeve@philips.co, E-mail: bernhard.gleich@philips.co, E-mail: joern.borgert@philips.co, E-mail: antonella.antonelli@uniurb.i, E-mail: carla.sfara@uniurb.i, E-mail: mauro.magnani@uniurb.i [Department of Biomolecular Sciences, University of Urbino, Via Saffi 2, Urbino, 61029 (Italy)

    2010-11-07

    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.

  2. Biochemically altered human erythrocytes as a carrier for targeted delivery of primaquine: an in vitro study.

    Science.gov (United States)

    Alanazi, Fars K; Harisa, Gamal El-Din I; Maqboul, Ahmad; Abdel-Hamid, Magdi; Neau, Steven H; Alsarra, Ibrahim A

    2011-04-01

    The aim of this study was to investigate human erythrocytes as a carrier for targeted drug delivery of primaquine (PQ). The process of PQ loading in human erythrocytes, as well as the effect of PQ loading on the oxidative status of erythrocytes, was also studied. At PQ concentrations of 2, 4, 6, and 8 mg/mL and an incubation time of 2 h, the ratios of the concentrations of PQ entrapped in erythrocytes to that in the incubation medium were 0.515, 0.688, 0.697 and 0.788, respectively. The maximal decline of erythrocyte reduced glutathione content was observed at 8 mg/mL of PQ compared with native erythrocytes p erythrocytes was increased in comparison with unloaded cells. Electron microscopy revealed spherocyte formation with PQ carrier erythrocytes. PQ-loaded cells showed sustained drug release over a 48 h period. Erythrocytes were loaded with PQ successfully, but there were some biochemical as well as physiological changes that resulted from the effect of PQ on the oxidative status of drug-loaded erythrocytes. These changes may result in favorable targeting of PQ-loaded cells to reticulo-endothelial organs. The relative impact of these changes remains to be explored in ongoing animal studies.

  3. Hybrid sequencing approach applied to human fecal metagenomic clone libraries revealed clones with potential biotechnological applications.

    Directory of Open Access Journals (Sweden)

    Mária Džunková

    Full Text Available Natural environments represent an incredible source of microbial genetic diversity. Discovery of novel biomolecules involves biotechnological methods that often require the design and implementation of biochemical assays to screen clone libraries. However, when an assay is applied to thousands of clones, one may eventually end up with very few positive clones which, in most of the cases, have to be "domesticated" for downstream characterization and application, and this makes screening both laborious and expensive. The negative clones, which are not considered by the selected assay, may also have biotechnological potential; however, unfortunately they would remain unexplored. Knowledge of the clone sequences provides important clues about potential biotechnological application of the clones in the library; however, the sequencing of clones one-by-one would be very time-consuming and expensive. In this study, we characterized the first metagenomic clone library from the feces of a healthy human volunteer, using a method based on 454 pyrosequencing coupled with a clone-by-clone Sanger end-sequencing. Instead of whole individual clone sequencing, we sequenced 358 clones in a pool. The medium-large insert (7-15 kb cloning strategy allowed us to assemble these clones correctly, and to assign the clone ends to maintain the link between the position of a living clone in the library and the annotated contig from the 454 assembly. Finally, we found several open reading frames (ORFs with previously described potential medical application. The proposed approach allows planning ad-hoc biochemical assays for the clones of interest, and the appropriate sub-cloning strategy for gene expression in suitable vectors/hosts.

  4. The reference range of serum, plasma and erythrocyte magnesium

    Directory of Open Access Journals (Sweden)

    Suzanna Immanuel

    2006-12-01

    Full Text Available The interest in the clinical importance of serum magnesium level has just recently begun with the analysis and findings of abnormal magnesium level in cardiovascular, metabolic and neuromuscular disorder. Although the serum level does not reflect the body magnesium level, but currently, only serum magnesium determination is widely used. Erythrocyte magnesium is considered more sensitive than serum magnesium as it reflects intracellular magnesium status. According to NCCLS (National Committee for Clinical Laboratory Standards every laboratory is recommended to have its own reference range for the tests it performs, including magnesium determination. The reference range obtained is appropriate for the population and affected by the method and technique. This study aimed to find the reference range of serum and plasma magnesium and also intracellular magnesium i.e. erythrocyte magnesium by direct method, and compare the results of serum and plasma magnesium. Blood was taken from 114-blood donor from Unit Transfusi Darah Daerah (UTDD Budhyarto Palang Merah Indonesia (PMI DKI Jakarta, consisted of 57 male and 57 female, aged 17 – 65 years, clinically healthy according to PMI donor criteria. Blood was taken from blood set, collected into 4 ml vacuum tube without anticoagulant for serum magnesium determination and 3 ml vacuum tube with lithium heparin for determination of erythrocyte and plasma magnesium Determination of magnesium level was performed with clinical chemistry auto analyzer Hitachi 912 by Xylidil Blue method colorimetrically. This study showed no significant difference between serum and heparinized plasma extra cellular magnesium. The reference range for serum or plasma magnesium was 1.30 – 2.00 mEq/L and for erythrocyte magnesium was 4.46 - 7.10 mEq/L. (Med J Indones 2006; 15:229-35Keywords: Reference range, extracellular magnesium, intracellular magnesium

  5. Purification and properties of enolase of human erythrocytes

    NARCIS (Netherlands)

    Hoorn, R.K.J.; Flikweert, J.P.; Staal, Gerard E.J.

    1974-01-01

    1. 1. Human erythrocyte enolase (2-phospho-D-glycerate hydrolyase, EC 4.2.1.11) was purified I000-fold. 2. 2. The pH-optimum was at pH 6.5. The molecular weight, estimated by gel filtration, was found to be 95,000 ± 5,000. 3. 3. Electrophoresis on agar-agarose at pH 8.5 and 6.4 showed only one

  6. Purification and properties of enolase of human erythrocytes

    NARCIS (Netherlands)

    Hoorn, R.K.J.; Flikweert, J.P.; Staal, Gerard E.J.

    1. 1. Human erythrocyte enolase (2-phospho-D-glycerate hydrolyase, EC 4.2.1.11) was purified I000-fold. 2. 2. The pH-optimum was at pH 6.5. The molecular weight, estimated by gel filtration, was found to be 95,000 ± 5,000. 3. 3. Electrophoresis on agar-agarose at pH 8.5 and 6.4 showed only one

  7. Erythrocyte glucose-6-phosphate dehydrogenase from Brazilian opossum Didelphis marsupialis

    Directory of Open Access Journals (Sweden)

    Barretto O.C. de O.

    2006-01-01

    Full Text Available In a comparative study of erythrocyte metabolism of vertebrates, the specific activity of glucose-6-phosphate dehydrogenase (G6PD of the Brazilian opossum Didelphis marsupialis in a hemolysate was shown to be high, 207 ± 38 IU g-1 Hb-1 min-1 at 37ºC, compared to the human erythrocyte activity of 12 ± 2 IU g-1 Hb-1 min-1 at 37ºC. The apparent high specific activity of the mixture led us to investigate the physicochemical properties of the opossum enzyme. We report that reduced glutathione (GSH in the erythrocytes was only 50% higher than in human erythrocytes, a value lower than expected from the high G6PD activity since GSH is maintained in a reduced state by G6PD activity. The molecular mass, determined by G-200 Sephadex column chromatography at pH 8.0, was 265 kDa, which is essentially the same as that of human G6PD (260 kDa. The Michaelis-Menten constants (Km: 55 µM for glucose-6-phosphate and nicotinamide adenine dinucleotide phosphate (Km: 3.3 µM were similar to those of the human enzyme (Km: 50-70 and Km: 2.9-4.4, respectively. A 450-fold purification of the opossum enzyme was achieved and the specific activity of the purified enzyme, 90 IU/mg protein, was actually lower than the 150 IU/mg protein observed for human G6PD. We conclude that G6PD after purification from the hemolysate of D. marsupialis does not have a high specific activity. Thus, it is quite probable that the red cell hyperactivity reported may be explained by increased synthesis of G6PD molecules per unit of hemoglobin or to reduced inactivation in the RBC hemolysate.

  8. Influence of calcium blockers on the SPR of erythrocytes

    Science.gov (United States)

    Shynkarenko, Olena V.; Tril, Orest; Wojnarowska, Renata; Prohorenko, Sergiy; Shergii, E. M.

    2017-01-01

    One of the promising areas of research is the impact of calcium channel blockers (CB) of biological fluids. This paper shows that the CB impact on a biological fluid can be efficiently combine with the surface plasmon resonance (SPR). It is shown that the addition of CB at the SPR measurements affect the stability of membranes and acts differently on the kinetics of erythrocytes ligament in the different groups of people.

  9. Observation on PI (Π) based dimensions of the erythrocyte

    African Journals Online (AJOL)

    This paper reports data, which suggests that the relative dimensions of the blood erythrocyte appear to be approximate powers of the number pi (Π = 3.14). The estimated dimensions are: center thickness = 0.81μm; rim thickness = 2.58μm; diameter = 7.82μm; circumference = 24.57μm. These yielded simple ratios of: 1.00: ...

  10. Effects of Aspirin on Rheological Properties of Erythrocytes In Vitro

    OpenAIRE

    Elblbesy, Mohamed A.; Hereba, Abdel Rahman M.; Shawki, Mamdouh M.

    2012-01-01

    Aspirin is of proven value as an antithrombotic drug. In unstable angina it reduces the risk of death and myocardial infarction by half. Most studies on the mechanism of action of aspirin have concentrated on the effect of aspirin on platelets. In the present study we have tried to prove that there is another biophysical mechanism of aspirin, and that is through the effect of aspirin on erythrocytes. In this study ten blood samples were incubated with aspirin at different concentrations. The ...

  11. Stability of erythrocyte suspensions layered on stationary and flowing liquids

    Science.gov (United States)

    Omenyi, S. N.; Rhodes, P. H.; Snyder, R. S.

    1982-01-01

    The apparent stability of erythrocyte suspensions layered on stationary and flowing Ficoll solutions was studied considering the effects of particle concentration, type and size, and the different flow rates of the particle suspensions and chamber liquid. The data from the flowing system were empirically fitted and, when extrapolated to zero chamber liquid flow rate, gave values comparable to the data from the stationary system, thus confirming the validity of the data and our approach to obtain that data.

  12. [Ratio of erythrocyte and plasma in massive blood transfusion].

    Science.gov (United States)

    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 (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 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 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.

  13. Piperlongumine-Induced Phosphatidylserine Translocation in the Erythrocyte Membrane

    Directory of Open Access Journals (Sweden)

    Rosi Bissinger

    2014-10-01

    Full Text Available Background: Piperlongumine, a component of Piper longum fruit, is considered as a treatment for malignancy. It is effective by inducing apoptosis. Mechanisms involved in the apoptotic action of piperlongumine include oxidative stress and activation of p38 kinase. In analogy to apoptosis of nucleated cells, erythrocytes may undergo eryptosis, the suicidal death of erythrocytes characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine-exposure at the erythrocyte surface. Signaling involved in eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i, formation of ceramide, oxidative stress and activation of p38 kinase. Methods: Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, [Ca2+]i from Fluo3 fluorescence, reactive oxygen species from 2',7'-dichlorodihydrofluorescein-diacetate fluorescence, and ceramide abundance from binding of fluorescent antibodies in flow cytometry. Results: A 48 h exposure to piperlongumine (30 µM was followed by significant decrease of forward scatter and increase of annexin-V-binding. Piperlongumine did not significantly modify [Ca2+]i and the effect was not dependent on presence of extracellular Ca2+. Piperlongumine significantly increased ROS formation and ceramide abundance. Conclusions: Piperlongumine triggers cell membrane scrambling, an effect independent from entry of extracellular Ca2+ but at least partially due to ROS and ceramide formation.

  14. Erythrocyte oxidative stress markers in children with sickle cell disease

    Directory of Open Access Journals (Sweden)

    Priscila Bacarin Hermann

    2016-08-01

    Full Text Available Abstract Objective To determine eight parameters of oxidative stress markers in erythrocytes from children with sickle cell disease and compare with the same parameters in erythrocytes from healthy children, since oxidative stress plays an important role in the pathophysiology of sickle cell disease and because this disease is a serious public health problem in many countries. Methods Blood samples were obtained from 45 children with sickle cell disease (21 males and 24 females with a mean age of 9 years; range: 3–13 years and 280 blood samples were obtained from children without hemoglobinopathies (137 males and 143 females with a mean age of 10 years; range: 8–11 years, as a control group. All blood samples were analyzed for methemoglobin, reduced glutathione, thiobarbituric acid reactive substances, percentage of hemolysis, reactive oxygen species, and activity of the enzymes glucose 6-phosphate dehydrogenase, superoxide dismutase, and catalase. Data were analyzed using Student's t-test and were expressed as the mean ± standard deviation. A p-value of <0.05 was considered significant. Results Significant differences were observed between children with sickle cell disease and the control group for the parameters methemoglobin, thiobarbituric acid reactive substances, hemolysis, glucose 6-phosphate dehydrogenase activity, and reactive oxygen species, with higher levels in the patients than in the controls. Conclusions Oxidative stress parameters in children's erythrocytes were determined using simple laboratory methods with small volumes of blood; these biomarkers can be useful to evaluate disease progression and outcomes in patients.

  15. Transformation of zearalenone and zearalenol by rat erythrocytes.

    Science.gov (United States)

    Chang, W M; Lin, J K

    1984-11-01

    The interconversion of zearalenone and zearalenol by rat erythrocytes in vitro has been investigated. The major metabolite obtained by incubating zearalenone with erythrocytes or whole blood from Sprague-Dawley rats was alpha-zearalenol. beta-Zearalenol was also formed but at levels several times lower than those of alpha-zearalenol. In the cell-free haemolysate NADPH was much more effective than NADH as a co-factor in the reduction of zearalenone. The maximal transformation of zearalenone to zearalenol by haemolysates occurred at pH 8.0. Both NAD+ and NADP+ were effective as co-factors in the oxidation of alpha-zearalenol to zearalenone. However, only NADP+ was effective as a co-factor in the oxidation of beta-zearalenol. Conversion of alpha-zearalenol and beta-zearalenol to the corresponding epimer was observed in both erythrocyte suspensions and in cell-free haemolysates. The significance of these findings to the metabolism of zearalenone in vivo is discussed.

  16. Rapamycin alleviates oxidative stress-induced damage in rat erythrocytes.

    Science.gov (United States)

    Singh, Abhishek Kumar; Singh, Sandeep; Garg, Geetika; Rizvi, Syed Ibrahim

    2016-10-01

    An imbalanced cellular redox system promotes the production of reactive oxygen species (ROS) that may lead to oxidative stress-mediated cell death. Erythrocytes are the best-studied model of antioxidant defense mechanism. The present study was undertaken to investigate the effect of the immunosuppressant drug rapamycin, an inducer of autophagy, on redox balance of erythrocytes and blood plasma of oxidatively challenged rats. Male Wistar rats were oxidatively challenged with HgCl2 (5 mg/kg body mass (b.m.)). A significant (p membrane redox system (PMRS), intracellular Ca2+ influx, lipid peroxidation (LPO), osmotic fragility, plasma protein carbonyl (PCO) content, and plasma advanced oxidation protein products (AOPP) and simultaneously significant reduction in glutathione (GSH) level and ferric reducing ability of plasma (FRAP) were observed in rats exposed to HgCl2. Furthermore, rapamycin (0.5 mg/kg b.m.) provided significant protection against HgCl2-induced alterations in rat erythrocytes and plasma by reducing ROS production, PMRS activity, intracellular Ca2+ influx, LPO, osmotic fragility, PCO content, and AOPP and also restored the level of antioxidant GSH and FRAP. Our observations provide evidence that rapamycin improves redox status and attenuates oxidative stress in oxidatively challenged rats. Our data also demonstrate that rapamycin is a comparatively safe immunosuppressant drug.

  17. Micronucleated Erythrocytes in Newborn Rats Exposed to Raltegravir Placental Transfer

    Directory of Open Access Journals (Sweden)

    Blanca Miriam Torres-Mendoza

    2014-01-01

    Full Text Available 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.

  18. Drug-loaded erythrocytes: on the road toward marketing approval

    Science.gov (United States)

    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

  19. Towards Clone Detection in UML Domain Models

    DEFF Research Database (Denmark)

    Störrle, Harald

    2013-01-01

    Code clones (i.e., duplicate fragments of code) have been studied for long, and there is strong evidence that they are a major source of software faults. Anecdotal evidence suggests that this phenomenon occurs similarly in models, suggesting that model clones are as detrimental to model quality...... as they are to code quality. However, programming language code and visual models have significant differences that make it difficult to directly transfer notions and algorithms developed in the code clone arena to model clones. In this article, we develop and propose a definition of the notion of “model clone” based...... on the thorough analysis of practical scenarios. We propose a formal definition of model clones, specify a clone detection algorithm for UML domain models, and implement it prototypically. We investigate different similarity heuristics to be used in the algorithm, and report the performance of our approach. While...

  20. Cloning cattle: the methods in the madness.

    Science.gov (United States)

    Oback, Björn; Wells, David N

    2007-01-01

    Somatic cell nuclear transfer (SCNT) is much more widely and efficiently practiced in cattle than in any other species, making this arguably the most important mammal cloned to date. While the initial objective behind cattle cloning was commercially driven--in particular to multiply genetically superior animals with desired phenotypic traits and to produce genetically modified animals-researchers have now started to use bovine SCNT as a tool to address diverse questions in developmental and cell biology. In this paper, we review current cattle cloning methodologies and their potential technical or biological pitfalls at any step of the procedure. In doing so, we focus on one methodological parameter, namely donor cell selection. We emphasize the impact of epigenetic and genetic differences between embryonic, germ, and somatic donor cell types on cloning efficiency. Lastly, we discuss adult phenotypes and fitness of cloned cattle and their offspring and illustrate some of the more imminent commercial cattle cloning applications.

  1. [Changes of erythrocyte deformability in rats acclimatized to hypoxia and its molemechanism].

    Science.gov (United States)

    Nie, Hong-Jing; Tian, Yun-Mei; Zhang, Dong-Xiang; Wang, Hai

    2011-02-01

    To observe the changes of erythrocyte deformability in rats acclimatized to hypoxia and its molemechanism. Male rats were randomly divided into three groups (n = 10): normal control group, acute hypoxia group and hypoxia acclimatization group. Animals were exposed to hypoxia for 0, 1, 28 d, blooded from their hearts after anaesthetized, respectively. Erythrocyte deformability, membrane fluidity, cholesterin and total lipid, lipid components of erythrocyte membrane, erythrocyte membrane ATPase and the concentrations of Na+ and Ca2+ were measured respectively. The two-dimensional electrophoresis maps of the rats erythrocyte membrane protein were achieved. The different protein spots were founded by image master 2D elite and identified by mass spectrum. (1) In acute hypoxia group, the deformability, membrane fluidity, the content of membrane cholesterin and total lipid were declined. The content of phosphatidylserines (PS), sphingomyelin (SM) in erythrocyte membrane lipids were increased, phosphatidylcholine (PC) reduced. The activity of ATP enzymes reduced and the concentration of Na+ and Ca2+ in erythrocyte increased. The two-dimensional electrophoresis maps of the rats erythrocyte membrane protein were achieved. Four of the seven protein spots selected increased and three of them showed no change. (2) In hypoxia acclimatization group, the deformability, membrane fluidity, the content of membrane cholesterin and total lipid were increased than those in acute hypoxia group, similar to normal group. The content of PS, SM in erythrocyte membrane lipids were reduced, PC increased. The activity of ATP enzymes induced and the concentration of Na+ and Ca2+ in erythrocyte increased after hypoxia acclimatization. Four of those protein spots mentioned increase and three declined after hypoxia acclimatization. They were respectively proved by mass spectrum to be alexin binding protein, aquaporin chip, membrane inhibitor reactive lysis, phospholipids scramblase, glucose

  2. Telomeres and the ethics of human cloning.

    Science.gov (United States)

    Allhoff, Fritz

    2004-01-01

    In search of a potential problem with cloning, I investigate the phenomenon of telomere shortening which is caused by cell replication; clones created from somatic cells will have shortened telomeres and therefore reach a state of senescence more rapidly. While genetic intervention might fix this problem at some point in the future, I ask whether, absent technological advances, this biological phenomenon undermines the moral permissibility of cloning.

  3. Altitude acclimatization and blood volume: effects of exogenous erythrocyte volume expansion

    DEFF Research Database (Denmark)

    Sawka, M N; Young, Jette Feveile; Rock, P B

    1996-01-01

    We studied sea-level residents during 13 days of altitude acclimatization to determine 1) altitude acclimatization effects on erythrocyte volume and plasma volume, 2) if exogenous erythrocyte volume expansion alters subsequent erythrocyte volume and plasma volume adaptations, 3) if an increased...... blood oxygen content alters erythropoietin responses during altitude acclimatization, and 4) mechanisms responsible for plasma loss at altitude. Sixteen healthy men had a series of hematologic measurements made at sea level, on the first and ninth days of altitude (4,300 m) residence, and after...... returning to sea level. Twenty-four hours before the ascent to altitude, one group received a 700-ml infusion of autologous erythrocytes (42% hematocrit), whereas the other group received only a saline infusion. Erythrocyte infusion increased erythrocyte volume by approximately 10%, whereas saline infusion...

  4. AN APPROACH FOR CLONE DETECTION IN DOCUMENTATION REUSE

    OpenAIRE

    D. V. Lutsiv; D. V. Koznov; H. A. Basit; E. L. Ouh; M. N. Smirnov; K. Y. Romanovsky

    2014-01-01

    The paper focuses on the searching method for repetitions in DocBook/DRL or plain text documents. An algorithm has been designed based on software clone detection. The algorithm supports filtering results: clones are rejected if clone length in the group is less than 5 symbols, intersection of clone groups is eliminated, meaningfulness clones are removed, the groups containing clones consisting only of XML are eliminated. Remaining search is supported: found clones are extracted from the docu...

  5. Genetic Diversity of Polymorphic Vaccine Candidate Antigens (Apical Membrane Antigen-1, Merozoite Surface Protein-3, and Erythrocyte Binding Antigen-175) in Plasmodium falciparum Isolates from Western and Central Africa

    Science.gov (United States)

    Soulama, Issiaka; Bigoga, Jude D.; Ndiaye, Magatte; Bougouma, Edith C.; Quagraine, Josephine; Casimiro, Prisca N.; Stedman, Timothy T.; Sirima, Sodiomon B.

    2011-01-01

    The malaria vaccine candidate antigens erythrocyte binding antigen 175 (EBA-175), merozoite surface protein 3 (MSP-3), and apical membrane antigen (AMA-1) from Plasmodium falciparum isolates from countries in central and west Africa were assessed for allelic diversity. Samples were collected on filter paper from 600 P. falciparum-infected symptomatic patients in Cameroon, Republic of Congo, Burkina Faso, Ghana, and Senegal and screened for class-specific amplification fragments. Genetic diversity, assessed by mean heterozygosity, was comparable among countries. We detected a clinical increase in eba 175 F-allele frequency from west to east across the study region. No statistical difference in msp-3 allele distribution between countries was observed. The ama-1 3D7 alleles were present at a lower frequency in central Africa than in West Africa. We also detected little to no genetic differentiation among sampling locations. This finding indicates that, at least at the level of resolution offered by restriction fragment length polymorphism analysis, these antigens showed remarkable genetic homogeneity throughout the region sampled, perhaps caused by balancing selection to maintain a diverse array of antigen haplotyes. PMID:21292899

  6. Human cloning: Eastern Mediterranean Region perspective.

    Science.gov (United States)

    Abdur Rab, M; Khayat, M H

    2006-01-01

    Recent advances in genomics and biotechnology have ushered in a new era in health development. Therapeutic cloning possesses enormous potential for revolutionizing medical and therapeutic techniques. Cloning technology, however, is perceived as having the potential for reproductive cloning, which raises serious ethical and moral concerns. It is important that the Islamic countries come to a consensus on this vital issue. Developing science and technology for better health is a religious and moral obligation. There is an urgent need for Muslim scholars to discuss the issue of stem cell research and cloning rationally; such dialogue will not only consider the scientific merits but also the moral, ethical and legal implications.

  7. Metabolomic phenotyping of a cloned pig model

    Directory of Open Access Journals (Sweden)

    Callesen Henrik

    2011-08-01

    Full Text Available Abstract Background Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs. Results The metabolic phenotype of cloned pigs (n = 5 was for the first time elucidated by nuclear magnetic resonance (NMR-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6 by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established. Conclusions From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals.

  8. Metabolomic phenotyping of a cloned pig model

    Science.gov (United States)

    2011-01-01

    Background Pigs are widely used as models for human physiological changes in intervention studies, because of the close resemblance between human and porcine physiology and the high degree of experimental control when using an animal model. Cloned animals have, in principle, identical genotypes and possibly also phenotypes and this offer an extra level of experimental control which could possibly make them a desirable tool for intervention studies. Therefore, in the present study, we address how phenotype and phenotypic variation is affected by cloning, through comparison of cloned pigs and normal outbred pigs. Results The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n = 6) by multivariate data analysis, which revealed differences in the metabolic phenotypes. Plasma lactate was higher for cloned vs control pigs, while multiple metabolites were altered in the bile. However a lower inter-individual variability for cloned pigs compared with control pigs could not be established. Conclusions From the present study we conclude that cloned and normal outbred pigs are phenotypically different. However, it cannot be concluded that the use of cloned animals will reduce the inter-individual variation in intervention studies, though this is based on a limited number of animals. PMID:21859467

  9. Species-specific challenges in dog cloning.

    Science.gov (United States)

    Kim, G A; Oh, H J; Park, J E; Kim, M J; Park, E J; Jo, Y K; Jang, G; Kim, M K; Kim, H J; Lee, B C

    2012-12-01

    Somatic cell nuclear transfer (SCNT) is now an established procedure used in cloning of several species. SCNT in dogs involves multiple steps including the removal of the nuclear material, injection of a donor cell, fusion, activation of the reconstructed oocytes and finally transfer to a synchronized female recipient. There are therefore many factors that contribute to cloning efficiency. By performing a retrospective analysis of 2005-2012 published papers regarding dog cloning, we define the optimum procedure and summarize the specific feature for dog cloning. © 2012 Blackwell Verlag GmbH.

  10. Quantum cloning disturbed by thermal Davies environment

    Science.gov (United States)

    Dajka, Jerzy; Łuczka, Jerzy

    2016-06-01

    A network of quantum gates designed to implement universal quantum cloning machine is studied. We analyze how thermal environment coupled to auxiliary qubits, `blank paper' and `toner' required at the preparation stage of copying, modifies an output fidelity of the cloner. Thermal environment is described in terms of the Markovian Davies theory. We show that such a cloning machine is not universal any more but its output is independent of at least a part of parameters of the environment. As a case study, we consider cloning of states in a six-state cryptography's protocol. We also briefly discuss cloning of arbitrary input states.

  11. Human cloning and our sense of self.

    Science.gov (United States)

    Brock, Dan W

    2002-04-12

    This Viewpoint formulates and responds to three lines of argument concerning human reproductive cloning's potential to undermine our sense of self or identity. First, cloning would undermine our sense of individuality or uniqueness. But it could only undermine our genetic uniqueness, not our full individuality. Second, cloning would undermine the value or worth of human beings. But it would not make individuals replaceable or of any less moral worth. Third, a clone's freedom or autonomy to construct his or her own life would be undermined by the presence of an earlier twin. But only a mistaken belief in genetic determinism supports this feared loss of freedom.

  12. Phenomenological implications of D3/D7 (reversed) µ-split-like ...

    Indian Academy of Sciences (India)

    2016-01-05

    Jan 5, 2016 ... some fine tuning, it is possible to obtain another light Higgs of mass 125 GeV. We discuss the role of the heavy quarks/sleptons and the light Higgs in (i) obtaining long-lived gluinos (a natural consequence ..... production mechanism, we estimated the gravitino relic abundance to be around 0.1 by evaluating ...

  13. Phenomenological implications of D3/D7 (reversed) µ-split-like ...

    Indian Academy of Sciences (India)

    2016-01-05

    Cheese Calabi–Yau string-theoretic compactification with a mobile 3- and fluxed stacks of wrapped 7-branes. It provides a natural realization of (reversed) -split-like supersymmetry wherein the squarks, sleptons, ...

  14. Data of evolutionary structure change: 1AKMA-3D7SC [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 15 7.253 1.00 72.69 C ATOM 625 CA SER A 81 34.219 50.951 3.873 1.00 90.99 C ...9 3.79 SER CA 6.51 3.80 GLY CA 3.90 SER CA -map>...64 3.82 THR CA 3.83 SER CA -map> SER CA 267...e>ATOM 971 CA TRP A 125 24.722 69.542 6.056 1.00 15.89 C -map> TR...VAL CA 3.81 TRP CA tance-map> LEU CA 397 ALA CA 39

  15. Nutrition and Reproductive Health: Sperm versus Erythrocyte Lipidomic Profile and ?-3 Intake

    OpenAIRE

    Gabriela Ruth Mendeluk; Mariano Isaac Cohen; Carla Ferreri; Chryssostomos Chatgilialoglu

    2015-01-01

    Fatty acid analyses of sperm and erythrocyte cell membrane phospholipids in idiopathic infertile patients evidenced that erythrocyte contents of EPA, DHA, omega-6–omega-3 ratio and arachidonic acid provide a mathematical correspondence for the prediction of EPA level in sperm cells. The erythrocyte lipidomic profile of patients was significantly altered, with signatures of typical Western pattern dietary habits and no fish intake. A supplementation with nutritional levels of EPA and DHA and a...

  16. Inhibition by Teriflunomide of Erythrocyte Cell Membrane Scrambling Following Energy Depletion, Oxidative Stress and Ionomycin

    National Research Council Canada - National Science Library

    Zierle, Jens; Bissinger, Rosi; Lang, Florian

    2016-01-01

    ... with translocation of phosphatidylserine to the erythrocyte surface. Triggers of cell membrane scrambling include energy depletion, oxidative stress and increase of cytosolic Ca2+ activity ([Ca2...

  17. [Density-specific distribution of erythrocytes in different types of anemia].

    Science.gov (United States)

    Shurkhina, E S; Nesterenko, V M; Kolodeĭ, S V; Tsvetaeva, N V; Ermakova, T A; Nikulina, O F; Kolosheĭnova, T I; Ataullakhanov, F I

    2009-01-01

    To study density-specific distribution of erythrocytes (DSDE) in different types of anemia. DSDE was determined in anemic patients by fractionation of the whole blood in hematocritic capillaries in the presence of mixtures of dimethyl- and dibutylphthalates with known density. Parameters are proposed which characterize DSDE changes typical for each type of anemia: mean erythrocyte density (MED)--mean density of total erythrocytic population; DSDE width (W)--a characteristic of erythrocytic population heterogeneity; light fraction of erythrocytes (LEF)--% of the cells with density less than 1.086 g/ml (hypochromic cells and reticulocytes); dense fraction of erythrocytes (DEF)--% of cells with density over 1.112 g/ml (hyperchromic cells forming as a result of erythrocyte dehydration). DSDE parameters for different types of anemia differed: reduced MED was typical for iron deficiency anemia (IDA) and paroxysmal nocturnal hemoglobinuria (PNH), increased DEF was seen in microspherocytic anemia (MSA), autoimmune hemolytic anemia (AHA), deficiency of glucose-6-phosphate dehydrogenase, increased LEF was observed in reticulocytosis in all anemia types except MSA, DSDE W was larger in MSA, AHA, PNA. DSDE is determined by proportion of erythropoiesis and sequestration of erythrocytes as well as pathological impacts leading to impairment of membrane permeability for cations and erythrocytic metabolism. Informative value of DSDE parameters makes them effective for diagnostic screening of anemias and control over course of different diseases.

  18. ATP release and extracellular nucleotidase activity in erythrocytes and coronary circulation of rainbow trout

    DEFF Research Database (Denmark)

    Jensen, Frank Bo; Agnisola, Claudio; Novak, Ivana

    2009-01-01

    The present study tested the hypothesis that rainbow trout erythrocytes release ATP upon deoxygenation, a mechanism that enables mammalian erythrocytes to produce local vasodilation. We also investigated ATP release and ectonucleotidase activity in the coronary circulation of the isolated trout...... heart. Erythrocytes suspended in an albumin-containing saline and equilibrated at physiological Pco2 showed negligible hemolysis (... in its absence, revealing the presence of ectonucleotidase activity. The induction of either a slow (minutes) or a fast (seconds) decrease in hemoglobin O2 saturation did not lead to additional ATP release. An elevation of Pco2 was also without influence on erythrocyte ATP release. In the saline...

  19. Kai 1 and Kai 2: Characterization of these dog erythrocyte antigens by monoclonal antibodies

    National Research Council Canada - National Science Library

    Jae Ho Lee; Urs Giger; Hee Young Kim

    2017-01-01

    Dog Erythrocyte Antigens (DEA) have thus far been found by sensitizing dogs with canine allogeneic blood and are clinically important regarding blood transfusion incompatibilities, but remain poorly defined...

  20. Pathomorphosis of erythrocytes in patients with acquired valvular heart diseases and under conditions of their correction.

    Science.gov (United States)

    Novitskii, V V; Ryazantseva, N V; Vecherskii, Yu Yu; Lapitskaya, O I; Stepovaya, E A

    2004-03-01

    Scanning electron microscopic study of the morphology and surface architectonics of erythrocytes in patients with acquired aortic and mitral valve diseases showed signs of morphological restructuring of the erythrocyte population. Reversibly transformed transitional red blood cells and irreversibly changed prehemolytical and degenerative erythrocytes were much more incident in these patients than in donors. The number of functionally intact biconcave discocytes notably decreased in comparison with donors. Morphological heterogeneity of the erythrocyte pool increased during the immediate period after replacement of heart valves with mechanical disc prostheses. Disorganization of the surface relief of red blood cells persisted 12-24 months after surgery.

  1. Future and applications of cloning.

    Science.gov (United States)

    Trounson, Alan O

    2006-01-01

    The birth of viable offspring from somatic cell nuclear transfer (SCNT) in mammals caused a major re-examination of the understanding of the commitment of cells to specific tissue lineages during differentiation. The questions of whether cells undergo dedifferentiation or transdifferentiation during the development of offspring and how these changes are controlled is a source of ongoing debate that is yet to be resolved. Irrespective of the outcome of this debate, it is clear that cloning using SCNT has a place and purpose in the future of research and animal breeding. The future uses of SCNT could include the production of transgenic mice, the production of transgenic livestock and assisting with the re-establishment of endangered species. Human medicine also would benefit from future use of SCNT because it would allow the production of patient-specific embryonic stem cells.

  2. Complex Minigene Library Vaccination for Discovery of Pre-Erythrocytic Plasmodium T Cell Antigens.

    Science.gov (United States)

    Stone, Brad C; Kas, Arnold; Billman, Zachary P; Fuller, Deborah H; Fuller, James T; Shendure, Jay; Murphy, Sean C

    2016-01-01

    Development of a subunit vaccine targeting liver-stage Plasmodium parasites requires the identification of antigens capable of inducing protective T cell responses. However, traditional methods of antigen identification are incapable of evaluating T cell responses against large numbers of proteins expressed by these parasites. This bottleneck has limited development of subunit vaccines against Plasmodium and other complex intracellular pathogens. To address this bottleneck, we are developing a synthetic minigene technology for multi-antigen DNA vaccines. In an initial test of this approach, pools of long (150 bp) antigen-encoding oligonucleotides were synthesized and recombined into vectors by ligation-independent cloning to produce two DNA minigene library vaccines. Each vaccine encoded peptides derived from 36 (vaccine 1) and 53 (vaccine 2) secreted or transmembrane pre-erythrocytic P. yoelii proteins. BALB/cj mice were vaccinated three times with a single vaccine by biolistic particle delivery (gene gun) and screened for interferon-γ-producing T cell responses by ELISPOT. Library vaccination induced responses against four novel antigens. Naïve mice exposed to radiation-attenuated sporozoites mounted a response against only one of the four novel targets (PyMDH, malate dehydrogenase). The response to PyMDH could not be recalled by additional homologous sporozoite immunizations but could be partially recalled by heterologous cross-species sporozoite exposure. Vaccination against the dominant PyMDH epitope by DNA priming and recombinant Listeria boosting did not protect against sporozoite challenge. Improvements in library design and delivery, combined with methods promoting an increase in screening sensitivity, may enable complex minigene screening to serve as a high-throughput system for discovery of novel T cell antigens.

  3. The ethics of human reproductive cloning.

    Science.gov (United States)

    Strong, Carson

    2005-03-01

    This article addresses the question of whether human reproductive cloning could be ethically justifiable in at least some cases involving infertile couples who would choose cloning as a way to have a genetically related child. At present, the risk of congenital anomalies constitutes a compelling argument against human reproductive cloning. The article explores whether reproductive cloning could be ethically justifiable if, at some future time, cloning becomes possible without an elevated risk of anomalies. It is argued that freedom to use cloning is a form of procreative freedom and, as such, deserves respect. All of the objections that have been raised against human reproductive cloning fall under three main categories: those that appeal to the interests of the child, those based on consequences for society, and those arising from teleological views. Objections that appeal to the child's interests are, in turn, of two main kinds: consequentialist and deontological. All of these types of objections are examined, and it is found that each involves serious problems that prevent it from being a reasonable objection in the context of the infertility cases considered. It is concluded that human reproductive cloning would be ethically justifiable in at least some cases involving infertile couples, provided that it could be performed without an elevated risk of anomalies.

  4. What's so bad about human cloning?

    Science.gov (United States)

    Breitowitz, Yitzchok

    2002-12-01

    There appears to be a consensus in the general community that reproductive cloning is an immoral technology that should be banned. It may, however, be argued, at least from the perspective of the Jewish tradition, that reproductive cloning has many positive benefits. It is thus essential that one carefully weigh the costs and the benefits before deciding on a definitive course of action.

  5. Computerized adaptive testing with item cloning

    NARCIS (Netherlands)

    Glas, Cornelis A.W.; van der Linden, Willem J.

    2003-01-01

    To increase the number of items available for adaptive testing and reduce the cost of item writing, the use of techniques of item cloning has been proposed. An important consequence of item cloning is possible variability between the item parameters. To deal with this variability, a multilevel item

  6. Recombination-assisted megaprimer (RAM) cloning

    Science.gov (United States)

    Mathieu, Jacques; Alvarez, Emilia; Alvarez, Pedro J.J.

    2014-01-01

    No molecular cloning technique is considered universally reliable, and many suffer from being too laborious, complex, or expensive. Restriction-free cloning is among the simplest, most rapid, and cost-effective methods, but does not always provide successful results. We modified this method to enhance its success rate through the use of exponential amplification coupled with homologous end-joining. This new method, recombination-assisted megaprimer (RAM) cloning, significantly extends the application of restriction-free cloning, and allows efficient vector construction with much less time and effort when restriction-free cloning fails to provide satisfactory results. The following modifications were made to the protocol:•Limited number of PCR cycles for both megaprimer synthesis and the cloning reaction to reduce error propagation.•Elimination of phosphorylation and ligation steps previously reported for cloning methods that used exponential amplification, through the inclusion of a reverse primer in the cloning reaction with a 20 base pair region of homology to the forward primer.•The inclusion of 1 M betaine to enhance both reaction specificity and yield. PMID:26150930

  7. Challenges in regulating farm animal cloning

    DEFF Research Database (Denmark)

    Gunning, Jennifer; Hartlev, Mette; Gamborg, Christian

    Report from the project Cloning in Public: A specific support action within the 6th framework programme, priority 5: Food quality and safety......Report from the project Cloning in Public: A specific support action within the 6th framework programme, priority 5: Food quality and safety...

  8. Cloning of endangered mammalian species: any progress?

    Science.gov (United States)

    Loi, Pasqualino; Galli, Cesare; Ptak, Grazyna

    2007-05-01

    Attempts through somatic cell nuclear transfer to expand wild populations that have shrunk to critical numbers is a logical extension of the successful cloning of mammals. However, although the first mammal was cloned 10 years ago, nuclear reprogramming remains phenomenological, with abnormal gene expression and epigenetic deregulation being associated with the cloning process. In addition, although cloning of wild animals using host oocytes from different species has been successful, little is known about the implication of partial or total mitochondrial DNA heteroplasmy in cloned embryos, fetuses and offspring. Finally, there is a need for suitable foster mothers for inter-intra specific cloned embryos. Considering these issues, the limited success achieved in cloning endangered animals is not surprising. However, optimism comes from the rapid gain in the understanding of the molecular clues underlying nuclear reprogramming. If it is possible to achieve a controlled reversal of the differentiated state of a cell then it is probable that other issues that impair the cloning of endangered animals, such as the inter-intra species oocyte or womb donor, will be overcome in the medium term.

  9. Cloning of partial putative gonadotropin hormone receptor ...

    Indian Academy of Sciences (India)

    Equus asinus. –. 71·0. –. Macaca fascicularis. –. 83·9. –. Gallus gallus. –. 74·2. –. Canis familiaris. –. –. 74·2. Drosophila melanogaster. –. 61·3. –. Figure 2. Structure of the cloned insert. (a) Diagrammatic representation of the cloned DNA fragment; arrangement of the PCR products are illustrated with primers. Letters 'F' and.

  10. Cloning and superluminal signaling£

    Indian Academy of Sciences (India)

    is possible, we can then have (usable) superluminal signaling [8]. The basic principle behind no exact cloning is the principle of no-signaling (i.e., no superluminal signaling). Allowing no-signaling, Gisin [7] has reproduced the 1. 2 optimal universal symmetric cloning machine of Buzek and Hillery [2] for qubits. We shall ...

  11. Metabolomic phenotyping of af cloned pig model

    DEFF Research Database (Denmark)

    Clausen, Morten Rahr; Christensen, Kirstine Lykke; Hedemann, Mette Skou

    2011-01-01

    outbred pigs. Results The metabolic phenotype of cloned pigs (n = 5) was for the first time elucidated by nuclear magnetic resonance (NMR)-based metabolomic analysis of multiple bio-fluids including plasma, bile and urine. The metabolic phenotype of the cloned pigs was compared with normal outbred pigs (n...

  12. Low magnesium concentration in erythrocytes of children with acute asthma.

    Science.gov (United States)

    Sedighi, Mostafa; Pourpak, Zahra; Bavarian, Behrouz; Safaralizadeh, Reza; Zare, Ahad; Moin, Mostafa

    2006-12-01

    Magnesium (Mg) is the second most abundant intracellular cation and is involved in numerous physiological functions, including protein folding, intracellular signaling and enzyme catalysis. It has been shown that magnesium deficiency exacerbates pulmonary airways hyper reactivity. Several studies suggest that magnesium level has no effect on asthma but others had shown a contributory effect. Because of its intracellular abundance the aim of this study was to determine if there was any difference in plasma and intracellular Mg concentrations of children with acute asthma compared to non asthmatic children. Twenty nine patients with acute asthma aged 2 to11 years admitted to the emergency department of hospital and 37 non asthmatic children with the same age were included in our study. 0.5 mL of heparinized whole blood samples of patients who were meeting inclusion criteria at the onset of admission with bronchoconstriction and before using any medication was drawn and it was immediately sent to the laboratory. Plasma and erythrocytes were separated and stored at -20C and later their Mg levels were quantified with atomic absorption spectrophotometry method. The average plasma and intracellular magnesium levels in patients were (0.79 +/- 0.098 mmol/L) and (1.17 +/- 0.27 mmol/L) respectively. Results of 37 non asthmatic persons [plasma (0.85 +/- 0.1 mmol/L ) and erythrocytes (1.33 +/- 0.21 mmol/L)] showed that there was no significant difference between plasma Mg levels in two groups (p 0.06) but intracellular magnesium level was significantly lower (p 0.03) in patients group. These results indicate that intracellular Mg level may be a more accurate method to assess Mg level in patients with asthma. Hence, determination of Mg concentration in erythrocytes may be used in evaluation of asthma pathophysiology. There are recommendations for using intravenous Mg sulfate in acute asthma, and this study supports the rational for using it in emergency departments for acute

  13. Associations of erythrocyte fatty acid patterns with insulin resistance.

    Science.gov (United States)

    Bigornia, Sherman J; Lichtenstein, Alice H; Harris, William S; Tucker, Katherine L

    2016-03-01

    Synergistic or additive effects or both on cardiometabolic risk may be missed by examining individual fatty acids (FAs). A pattern analysis may be a more useful approach. In addition, it remains unclear whether erythrocyte FA composition relates to insulin resistance among Hispanics/Latinos. We derived erythrocyte FA patterns for a Puerto Rican cohort and examined their association with diet and insulin resistance in cross-sectional and prospective analyses. At baseline, principal components analysis was used to derive factor patterns with the use of 24 erythrocyte FAs from 1157 participants of the Boston Puerto Rican Health Study (aged 45-75 y). Dietary intake was assessed with a validated semiquantitative food-frequency questionnaire. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated at baseline and at the 2-y follow-up. Relations between FA patterns and HOMA-IR were analyzed in a sample of 922 participants with available data. Five FA patterns were derived, differentiated by 1) relatively high de novo lipogenesis (DNL) FAs and low n-6 (ω-6) FAs, 2) high very-long-chain saturated FAs, 3) high n-3 (ω-3) FAs, 4) high linoleic acid and low arachidonic acid, and 5) high trans FAs. The DNL pattern was positively correlated with sugar and inversely with n-6 and monounsaturated FA intakes. Only the DNL pattern was positively related to baseline HOMA-IR [adjusted geometric means (95% CIs) for quartiles 1 and 4: 1.72 (1.58, 1.87) and 2.20 (2.02, 2.39); P-trend insulin sensitivity in a Hispanic/Latino cohort. © 2016 American Society for Nutrition.

  14. Dietary plasmalogen increases erythrocyte membrane plasmalogen in rats

    Directory of Open Access Journals (Sweden)

    Mawatari Shiro

    2012-11-01

    Full Text Available Abstract Background Many disorders with plasmalogen deficiency have been reported. Replenishment or replacement of tissue plasmalogens of these disorders would be beneficial to the patients with these disorders, but effects of dietary plasmalogen on mammals have not been reported. Methods Plasmalogens were purified from chicken skin. The purified plasmalogens consisted of 96.4% ethanolamine plasmalogen (PlsEtn, 2.4% choline plasmalogen (PlsCho and 0.5% sphingomyelin (SM. A diet containing 0.1% the purified plasmalogens (PlsEtn diet was given to rats. Relative composition of phospholipids was measured by a high performance liquid chromatography (HPLC method that can separate intact plasmalogens and all other phospholipid classes by a single chromatographic run. Results The PlsEtn diet given to Zucker diabetic fatty (ZDF rats for 4 weeks caused decreases of plasma cholesterol and plasma phospholipid as compared to control diet. The other routine laboratory tests of plasma including triacylglycerol, glucose, liver and renal functions, albumin, and body weight were not different. Relative compositions of erythrocyte PlsEtn and phosphatidylethanolamine (PE increased, and that of phosphatidylcholine (PC decreased in PlsEtn diet group. The PlsEtn diet given to normal rats for 9 weeks again caused decrease of plasma cholesterol and phospholipid, and it induced increase of relative composition of PlsEtn of the erythrocyte membrane. The other routine laboratory tests of plasma and body weight were not different. Conclusions Dietary PlsEtn increases relative composition of PlsEtn of erythrocyte membranes in normal and ZDF rats, and it causes decreases of plasma cholesterol and plasma phospholipids. Dietary PlsEtn for 9 weeks seemingly causes no adverse effect to health of normal rats.

  15. [Human cloning in Muslim and Arab law].

    Science.gov (United States)

    Aldeeb Abu-Sahlieh, Sami A

    2009-01-01

    Cloning is a modern medical procedure that Muslim religious authorities treat en resorting to the general principles established by classical Muslim law based on the Koran and the Sunnah of Muhhamad as the messenger of God. In this regard, human beings are not capable of deciding what is or what is not lawful without resorting to divine norms. Cloning clashes with several principles. Firstly, the principle of the respect for life in relation to surpernumeraries, but Muslim authors are not in unanimous agreement on the determination of the moment at which life begins. Secondly, is the respect of progeny: cloning could only take place between a married couple. But even if these two principles are respected, cloning poses two major problems: the diversity of species expounded by the Koran and the Sunnah and a lack of interest. Which explains the quasi-unanimous opposition of Muslim writings regarding cloning.

  16. "Goodbye Dolly?" The ethics of human cloning.

    Science.gov (United States)

    Harris, J

    1997-01-01

    The ethical implications of human clones have been much alluded to, but have seldom been examined with any rigour. This paper examines the possible uses and abuses of human cloning and draws out the principal ethical dimensions, both of what might be done and its meaning. The paper examines some of the major public and official responses to cloning by authorities such as President Clinton, the World Health Organisation, the European parliament, UNESCO, and others and reveals their inadequacies as foundations for a coherent public policy on human cloning. The paper ends by defending a conception of reproductive rights of "procreative autonomy" which shows human cloning to be not inconsistent with human rights and dignity. PMID:9451604

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

    Science.gov (United States)

    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. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  18. Decreased erythrocyte superoxide dismutase in elderly men with early nuclear cataract

    Directory of Open Access Journals (Sweden)

    Rose Rose

    2015-12-01

    Full Text Available BACKGROUND Imbalance between oxidative processes and antioxidant defenses has been considered to play a role in cataractogenesis, particularly in diabetes patients. Superoxide dismutase (SOD is an important precursor for oxidative stress in the human lens, and its activity is mainly dependent on the copper and zinc levels in the body. The aim of this study was to compare erythrocyte SOD, erythrocyte zinc and total serum testosterone levels in male patients with early senile nuclear cataract and evaluate the correlations between the parameters in all subjects. METHODS A community-based study of cross-sectional design was conducted at Cilandak District Primary Health Center where 52 adult and 17 elderly men with early senile nuclear cataract were chosen as the study subjects. Erythrocyte SOD, erythrocyte zinc, serum testosterone, and fasting blood glucose (FBG levels were measured in all subjects. Nuclear cataract stage was assessed with the Pentacam® instrument (Oculus, Germany. Independent Student t test and Pearson’s correlation were used to analyze the results. RESULTS Erythrocyte SOD level was significantly decreased in elderly men compared to adult men (p=0.014. Erythrocyte zinc, serum testosterone and FBG did not differ significantly in adult and elderly males (at p=0.304; p=0.145;and p=0.376, respectively. Erythrocyte SOD activity was significantly associated with erythrocyte zinc level (r=0.486; p=0.048. CONCLUSIONS Lower erythrocyte SOD activity was found in elderly males than in adult males with early nuclear cataract. There was a relationship between erythrocyte SOD and erythrocyte zinc level in elderly males with early nuclear cataract.

  19. Probing Volume Changes and the Intracellular Water in Single Erythrocytes

    Science.gov (United States)

    Park, Sanghoon; Arora, Silki; Mauser, Jennifer; Chakrabarti, Debopam; Schulte, Alfons

    2012-02-01

    In the living cell, water is one of the most abundant substances, and cells have developed very efficient machinery for transporting water in and out. Erythrocytes can undergo large, but reversible, volume changes under hydrostatic pressure and a possible mechanism may involve transport of water. We employ confocal micro-Raman spectroscopy over the frequency range from 150 to 4000 cm-1 to probe both the intracellular hemoglobin and water in individual red blood cells under physiological conditions. We investigate changes in the OH stretch bands near 3400 cm-1 due to the cellular water. Results of experiments that employ variations in external parameters such as pressure will be presented.

  20. [Presentation of a method of interpreting erythrocyte deformability].

    Science.gov (United States)

    Cortinovis, A; Crippa, A; Sciacca, V; Caravaggio, V

    1988-05-01

    The physical principles of a method based on a haematic double filtration, according to Reid classic technique is explained. The aim is to determine a method for researching the characteristics of erythrocytic deformability, without changing the original medium, exoerythrocytic essential component of the membrane physiochemical quality and intraerythrocytic for the fast, active exchanges, after an evaluation of different techniques and instrumentation. A practical example for calculating the factor of correction, with reference to personal material, is made. This method has the advantage that it does not need the manipulation of the sample and does not delay the determination.

  1. Effects of Alcohol on Membrane Fluidity of Human Erythrocyte

    OpenAIRE

    Mori, Ichiya; Hiramatsu, Midori; Toda, Naomi; Koide, Yayoi; Miyagawa, Fumio

    1994-01-01

    Membrane fluidity in human erythrocytes was measured by a spin label method using an electron spin resonance spectrometer in healthy volunteers after ingestion of alcohol (1.5 ml of whisky/kg body weight). Fluidity in the lipid bilayer closer to the hydrophilic face decreased at 30 min and 90 min, and fluidity in the hydrophobic core decreased at 90 min after ingestion of alcohol. In the same experiment, the level of thiobarbituric acid reactive substances in the serum decreased 30 min after ...

  2. Anomalous diffusion of erythrocytes in the presence of polyvinylpyrrolidone.

    Science.gov (United States)

    Fritz, O G

    1984-01-01

    The diffusion coefficient of erythrocytes was measured using quasi-elastic light-scattering (QELS) techniques. The cells were suspended in phosphate-buffered saline solutions with and without a macromolecule, polyvinylpyrrolidone (PVP[360]). In the presence of the PVP(360) an anomalously high diffusion coefficient was measured for metabolizing cells with a normal transmembrane potential. The results are in agreement with experiments on rouleau formation by red blood cells and are supportive of the hypothesis of a long-range coherent interaction between metabolically active biological cells. Images FIGURE 8 FIGURE 9 FIGURE 10 PMID:6478035

  3. Erythrocyte glutathione levels in lithium-induced hypothyroidism.

    Science.gov (United States)

    Engin, Atilla; Altan, Nilgun; Isik, Erdal

    2005-01-01

    Lithium, widely used in the prophylaxis of psychiatric patients with bipolar affective disorders, is well known to induce thyroid alterations. However, a possible metabolic linkage between blood thyroxine levels and its regulatory function on erythrocyte glutathione concentration has not yet been evaluated in lithium-treated patients. The aim of this study was to assess the antioxidative capacity of erythrocytes in lithium-induced hypothyroidism before and after thyroxine replacement. Thyroid ultrasound with clinical and laboratory evaluation of thyroid function and thyroid-stimulating hormone assay were performed prior to and at 6-month intervals during lithium prophylaxis in 76 patients with bipolar affective disorders. The daily lithium dosage was adjusted to 600-1200 mg and the mean duration of treatment was 2.2 +/- 0.4 years. Final assessment revealed that 12 patients had evidence of primary hypothyroidism, and these were assigned as the test group. Lithium prophylaxis was supplemented with thyroxine at a dosage of 100 mg/day within 6 months after thyroid dysfunction was diagnosed. Red blood cell superoxide dismutase activities and the glutathione contents were measured before and after thyroxine replacement. In order to assess the effect of long-term lithium administration on red blood cell glutathione and superoxide dismutase levels, 12 patients who had not developed hypothyroidism during the follow-up period were selected for the lithium-treated euthyroid group. Mann Whitney U-test and Wilcoxon rank sum W-test were used for comparison of data. A comparison of the lithium-treated test group with healthy volunteers and their own values after thyroxine replacement revealed a significant decrease in red blood cell glutathione concentrations (p = 0.000) in the hypothyroid state. However, no clinically significant changes were observed in red blood cell superoxide dismutase activities of the test group. A statistical survey also demonstrated that there was no

  4. Erythrocyte volume in acidified venous blood from exercising limbs.

    Science.gov (United States)

    Van Beaumont, W.; Rochelle, R. H.

    1973-01-01

    Five male volunteers performed arm exercises in the sitting position by cranking the pedals of a bicycle ergometer at 50 revolutions per min. The initial mechanical work load of 0 kgm/min was increased every minute by 75 kgm/min until exhaustion occurred. The data obtained show a significant acidification of the venous blood from the working arms and a substantial increase in venous pCO2 during this type of muscular activity. However, the erythrocyte volume remained unaltered during the exercise.

  5. AQUA Cloning: A Versatile and Simple Enzyme-Free Cloning Approach.

    Directory of Open Access Journals (Sweden)

    Hannes M Beyer

    Full Text Available Assembly cloning is increasingly replacing conventional restriction enzyme and DNA-ligase-dependent cloning methods for reasons of efficiency and performance. Here, we describe AQUA (advanced quick assembly, a simple and versatile seamless assembly cloning approach. We demonstrate the applicability and versatility of AQUA Cloning in selected proof-of-principle applications including targeted insertion-, deletion- and site-directed point-mutagenesis, and combinatorial cloning. Furthermore, we show the one pot de novo assembly of multiple DNA fragments into a single circular plasmid encoding a complex light- and chemically-regulated Boolean A NIMPLY B logic operation. AQUA Cloning harnesses intrinsic in vivo processing of linear DNA fragments with short regions of homology of 16 to 32 bp mediated by Escherichia coli. It does not require any kits, enzymes or preparations of reagents and is the simplest assembly cloning protocol to date.

  6. No decreased erythrocyte deformability in type 1 (insulin-dependent) diabetes, either by filtration or by ektacytometry

    NARCIS (Netherlands)

    Schut, N. H.; van Arkel, E. C.; Hardeman, M. R.; Bilo, H. J.; Michels, R. P.; Vreeken, J.

    1993-01-01

    A lower erythrocyte deformability, which causes impairment of the microcirculation, is postulated to contribute to diabetic organ complications. Erythrocyte deformability was measured in four groups of type 1 (insulin-dependent) diabetic subjects and 30 controls by filtration and ektacytometry.

  7. Electron Pathways through Erythrocyte Plasma Membrane in Human Physiology and Pathology: Potential Redox Biomarker?

    Directory of Open Access Journals (Sweden)

    Elena Matteucci

    2007-01-01

    Full Text Available Erythrocytes are involved in the transport of oxygen and carbon dioxide in the body. Since pH is the influential factor in the Bohr-Haldane effect, pHi is actively maintained via secondary active transports Na+/H+ exchange and HC3 -/Cl- anion exchanger. Because of the redox properties of the iron, hemoglobin generates reactive oxygen species and thus, the human erythrocyte is constantly exposed to oxidative damage. Although the adult erythrocyte lacks protein synthesis and cannot restore damaged proteins, it is equipped with high activity of protective enzymes. Redox changes in the cell initiate various signalling pathways. Plasma membrane oxido-reductases (PMORs are transmembrane electron transport systems that have been found in the membranes of all cells and have been extensively characterized in the human erythrocyte. Erythrocyte PMORs transfer reducing equivalents from intracellular reductants to extracellular oxidants, thus their most important role seems to be to enable the cell respond to changes in intra- and extra-cellular redox environments.So far the activity of erythrocyte PMORs in disease states has not been systematically investigated. This review summarizes present knowledge on erythrocyte electron transfer activity in humans (health, type 1 diabetes, diabetic nephropathy, and chronic uremia and hypothesizes an integrated model of the functional organization of erythrocyte plasma membrane where electron pathways work in parallel with transport metabolons to maintain redox homeostasis.

  8. Effects of Polyelectrolyte Microcapsules with Different Surface Charge on Erythrocyte Sedimentation Rate.

    Science.gov (United States)

    Naumov, A A; Dubrovskii, A V; Potselueva, M M; Tikhonenko, S A

    2017-05-01

    Relationship between changes in the erythrocyte sedimentation rate in rats and concentration and charge of polyelectrolyte microcapsules was studied by the Panchenkov method. Positively charged microcapsules reduced erythrocyte sedimentation rate in a concentrationdependent manner. This effect was related to a decrease in the content of high-molecularweight proteins in the plasma due to their adsorption in positively charged microcapsules with polyacrylamide surface layer.

  9. In Vivo distribution of hydrocortisone over whole blood : A novel method for the extraction of erythrocytes

    NARCIS (Netherlands)

    Driessen, O.; Treuren, L.; Moolenaar, A.; Meijer, J.W.A.; Verheijen, P.

    1990-01-01

    Ten mg hydrocortisone (HC) was administered intravenously to a healthy volunteer after a dexamethasone suppresion test and HC concentrations were determined from 1-270 min in plasma, plasma water and on erythrocytes. HC was extracted front erythrocyte concentrates with high efficiency by HC-poor

  10. Erythrocyte migration and gap formation in rabbit blood clots in vitro.

    Science.gov (United States)

    Ueki, T; Yazama, F; Horiuchi, T; Yamada, M

    2008-04-01

    Thrombolytic agents must be carried by the blood circulation to thrombi to exert their functions. Structural gaps exist between blood vessels and thrombi or in the area surrounding thrombi. Therefore, information about fundamental gap formation at thrombotic areas is critically important for thrombolytic therapy. We previously reported that t-PA accelerates the activities of bovine erythrocytes and hemoglobin (Hb) towards bovine plasminogen activation. Here, we examined gap generation by observing morphological changes during thrombolytic processes in rabbit blood clots deformation of erythrocytes from blood clots and Hb transfer from erythrocytes to serum in vitro. Rabbit venous blood samples (1 ml) were stored under sterile conditions in glass tubes at 37 degrees C for 2, 24, 48 h, 1, and 2 weeks. We examined clot diameter, erythrocyte diameter and number as well as Hb volume in the serum, as well as histological changes in the clots. The diameter of blood clots did not change until 2 weeks after sampling. Erythrocyte diameter decreased within 48 h and at 2 weeks after sampling at the clot surface (p erythrocytes in the serum started to increase starting from 24 h after sampling (p erythrocyte envelope became disrupted and cytoplasm started to flow through pores into the serum at 24 h. The results indicated that blood clots are reduced due to clot retraction, erythrocyte dissociation and cytoplasm leakage without a distinct fibrinolytic reaction. These results indicated that gaps start to form between 2 and 24 h after blood clotting.

  11. Platelet-independent adhesion of calcium-loaded erythrocytes to von Willebrand factor

    NARCIS (Netherlands)

    Smeets, M.W.J. (Michel W.J.); R. Bierings (Ruben); Meems, H. (Henriet); F.P.J. Mul (F. P J); D. Geerts (Dirk); A.P.J. Vlaar (Alexander); J. Voorberg (Jan); P.L. Hordijk (Peter )

    2017-01-01

    textabstractAdhesion of erythrocytes to endothelial cells lining the vascular wall can cause vaso-occlusive events that impair blood flow which in turn may result in ischemia and tissue damage. Adhesion of erythrocytes to vascular endothelial cells has been described in multiple hemolytic disorders,

  12. Sesquicentennial of the birth of Edmund Faustinus Biernacki, a discoverer of the erythrocyte sedimentation rate.

    Science.gov (United States)

    Kucharz, Eugeniusz J

    2017-01-01

    Edmund Faustinus Biernacki (1866-1911) was a Polish physician and philosopher of medicine. He described erythrocyte sedimentation, designed equipment to measure the erythrocyte sedimentation rate, and applied it to clinical practice. His contribution to the development of one of the most commonly used medical laboratory tests is forgotten, and the test is attributed to other scientists.

  13. An ex vivo study of nitric oxide efflux from human erythrocytes in both genders.

    Science.gov (United States)

    Duarte, Catarina; Napoleão, Patrícia; Freitas, Teresa; Saldanha, Carlota

    2016-01-01

    Acetylcholinesterase (AChE) is located on outer surface of erythrocyte membrane. Gender-related differences in erythrocyte AChE enzyme activity had been verified in young adults. It is also known that binding of acetylcholine (ACh) with AChE on erythrocyte membrane initiates a signal transduction mechanism that stimulates nitric oxide (NO) efflux. This ex vivo study was done to compare the amount of NO efflux obtained from erythrocytes of healthy donors in males and females. We included 66 gender age-matched healthy donors (40-60 years old). We performed quantification of erythrocyte NO efflux from erythrocytes and of the membrane AChE enzyme activity. There are no significant differences in NO efflux from erythrocytes between men and women. Regarding AChE enzyme activity values, in this range of age, no differences between genders were obtained. However, the values of AChE enzyme activity in the third quartile of NO efflux values were significantly higher (p gender. For the same range of values of NO efflux from erythrocytes, in both gender, it was verified higher values of AChE enzyme activity in women.

  14. Triggers, Inhibitors, Mechanisms, and Significance of Eryptosis: The Suicidal Erythrocyte Death

    Directory of Open Access Journals (Sweden)

    Elisabeth Lang

    2015-01-01

    Full Text Available 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.

  15. CD47 in Erythrocyte Ageing and Clearance - the Dutch Point of View

    NARCIS (Netherlands)

    Burger, Patrick; de Korte, Dirk; van den Berg, Timo K.; van Bruggen, Robin

    2012-01-01

    Recently, an important role for CD47, a well-known 'don't eat me' signal, in the clearance of aged erythrocytes was revealed. Experimental data support the conversion of CD47 from a 'don't eat me' to an 'eat me' signal through a conformational change in CD47. Intriguingly, erythrocyte phagocytosis

  16. The erythrocyte sedimentation rate, rouleaux formation and hyperviscosity syndrome. Theory and fact.

    Science.gov (United States)

    Ballas, S K

    1975-01-01

    Uncomplicated hyperviscosity syndrome secondary to hypergammaglobulinemic states seems to be associated with rouleaux formation on the peripheral blood film and a normal or near normal erythrocyte sedimentation rate. Conversely, the concomitant finding of rouleaux formation with a normal erythrocyte sedimentation rate is highly suggestive of the hyperviscosity syndrome. The theoretical and factual justifications for this hypothesis are presented.

  17. Host erythrocyte polymorphisms and exposure to Plasmodium falciparum in Papua New Guinea.

    NARCIS (Netherlands)

    Fowkes, F.J.; Michon, P.; Pilling, L.; Ripley, R.M.; Tavul, L.; Imrie, H.J.; Woods, C.M.; Mgone, C.S.; Luty, A.J.F.; Day, K.P.

    2008-01-01

    BACKGROUND: The protection afforded by human erythrocyte polymorphisms against the malaria parasite, Plasmodium falciparum, has been proposed to be due to reduced ability of the parasite to invade or develop in erythrocytes. If this were the case, variable levels of parasitaemia and rates of

  18. Plasmodium falciparum Erythrocyte Membrane Protein 1 Diversity in Seven Genomes – Divide and Conquer

    DEFF Research Database (Denmark)

    Rask, Thomas Salhøj; Hansen, Daniel Aaen; Theander, Thor G.

    2010-01-01

    The var gene encoded hyper-variable Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family mediates cytoadhesion of infected erythrocytes to human endothelium. Antibodies blocking cytoadhesion are important mediators of malaria immunity acquired by endemic populations. The development...

  19. Sheep erythrocyte membrane binding and transfer of long-chain fatty acids

    DEFF Research Database (Denmark)

    Bojesen, Inge Norby; Bojesen, Eigil

    1999-01-01

    Palmitic acid, oleic acid, linoleic acid, arachidonic acid, sheep erythrocyte ghosts, transporting elements, transport kinetics, fatty acid transport, transport rate constants......Palmitic acid, oleic acid, linoleic acid, arachidonic acid, sheep erythrocyte ghosts, transporting elements, transport kinetics, fatty acid transport, transport rate constants...

  20. Sequential, ordered acquisition of antibodies to Plasmodium falciparum erythrocyte membrane protein 1 domains

    DEFF Research Database (Denmark)

    Cham, Gerald K K; Turner, Louise; Lusingu, John

    2009-01-01

    The binding of erythrocytes infected with mature blood stage parasites to the vascular bed is key to the pathogenesis of malignant malaria. The binding is mediated by members of Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family. PfEMP1s can be divided into groups, and it has...

  1. Informativeness of polarization measurements in determining microphysical parameters of native erythrocyte populations

    Science.gov (United States)

    Kugeiko, M. M.; Smunev, D. A.

    2017-09-01

    The efficiency of polarized and nonpolarized radiation for determining microphysical parameters of native erythrocyte populations has been studied. On the basis of using regression relations between determined and measured parameters of native erythrocyte populations, possibilities of the simultaneous rapid determination of their average volume and average surface area, which can be used as a new diagnostic erythrocytometric parameter, are demonstrated.

  2. Triggers, Inhibitors, Mechanisms, and Significance of Eryptosis: The Suicidal Erythrocyte Death

    Science.gov (United States)

    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

  3. Expression of Plasmodium falciparum erythrocyte membrane protein 1 in experimentally infected humans

    DEFF Research Database (Denmark)

    Lavstsen, Thomas; Magistrado, Pamela; Hermsen, Cornelus C

    2005-01-01

    -encoded Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family, which is expressed on the surface of infected erythrocytes where it mediates binding to endothelial receptors. Thus, severe malaria may be caused by parasites expressing PfEMP1 variants that afford parasites optimal sequestration...

  4. The knocked-out erythrocyte sedimentation rate: periodontal abscess.

    Science.gov (United States)

    Sevinc, Alper; Bayindir, Yasar; But, Ayse

    2008-01-01

    The erythrocyte sedimentation rate (ESR) is a common but nonspecific test that is often used as an indicator of active disease. Infection of dental origin may be responsible for a number of cases in unresolved elevated ESR and fever etiology. Dental sepsis is the one of the potential causes of persistent fever that can escape detection. An 18-year-old female patient was admitted to the emergency room with complaints of headache, fever, nausea, and vomiting for the past four days. Erythrocyte sedimentation rate was 110 mm/h. She was started empirically on antibiotic treatment as no etiology was found. Four days later, while searching for the etiology of the fever, the patient experienced an acute pain in association with localizing symptoms in two decayed teeth. Oral examination revealed abscess formation in both teeth. Teeth were extracted and ESR was decreased to 95 mm/h on the day of the second extraction and to 60, 35, and 10 mm/h taken weekly. During the follow-up, she was in good health with no fever seen 3 months after treatment and her ESR was 15 mm/h. Dental infection should be considered as an unusual but very treatable cause of pyrexia of unknown origin.

  5. Reduced PKC α Activity Induces Senescent Phenotype in Erythrocytes

    Directory of Open Access Journals (Sweden)

    Rukmini B. Govekar

    2012-01-01

    Full Text Available The molecular mechanism mediating expression of senescent cell antigen-aggregated or cleaved band 3 and externalized phosphatidylserine (PS on the surface of aged erythrocytes and their premature expression in certain anemias is not completely elucidated. The erythrocytes with these surface modifications undergo macrophage-mediated phagocytosis. In this study, the role of protein kinase C (PKC isoforms in the expression of these surface modifications was investigated. Inhibition of PKC α by 30 μM rottlerin (R30 and 2.3 nM Gö 6976 caused expression of both the senescent cell marker-externalized PS measured by FACS analysis and aggregated band 3 detected by western blotting. In contrast to this observation, but in keeping with literature, PKC activation by phorbol-12-myristate-13-acetate (PMA also led to the expression of senescence markers. We explain this antithesis by demonstrating that PMA-treated cells show reduction in the activity of PKC α, thereby simulating inhibition. The reduction in PKC α activity may be attributed to the known downregulation of PMA-activated PKC α, caused by its membrane translocation and proteolysis. We demonstrate membrane translocation of PKC α in PMA-treated cells to substantiate this inference. Thus loss of PKC α activity either by inhibition or downregulation can cause surface modifications which can trigger erythrophagocytosis.

  6. Altered erythrocyte Na-K pump in anorectic patients

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Modulation of Erythrocyte Plasma Membrane Redox System Activity by Curcumin

    Directory of Open Access Journals (Sweden)

    Prabhakar Singh

    2016-01-01

    Full Text Available 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.

  8. Plasmodium falciparum erythrocyte invasion: combining function with immune evasion.

    Directory of Open Access Journals (Sweden)

    Gavin J Wright

    2014-03-01

    Full Text Available All the symptoms and pathology of malaria are caused by the intraerythrocytic stages of the Plasmodium parasite life cycle. Because Plasmodium parasites cannot replicate outside a host cell, their ability to recognize and invade erythrocytes is an essential step for both parasite survival and malaria pathogenesis. This makes invasion a conceptually attractive vaccine target, especially because it is one of the few stages when the parasite is directly exposed to the host humoral immune system. This apparent vulnerability, however, has been countered by the parasite, which has evolved sophisticated molecular mechanisms to evade the host immune response so that parasites asymptomatically replicate within immune individuals. These mechanisms include the expansion of parasite invasion ligands, resulting in multiple and apparently redundant invasion "pathways", highly polymorphic parasite surface proteins that are immunologically distinct, and parasite proteins which are poorly immunogenic. These formidable defences have so far thwarted attempts to develop an effective blood-stage vaccine, leading many to question whether there really is an exploitable chink in the parasite's immune evasion defences. Here, we review recent advances in the molecular understanding of the P. falciparum erythrocyte invasion field, discuss some of the challenges that have so far prevented the development of blood-stage vaccines, and conclude that the parasite invasion ligand RH5 represents an essential pinch point that might be vulnerable to vaccination.

  9. Human embryo cloning prohibited in Hong Kong.

    Science.gov (United States)

    Liu, Athena

    2005-12-01

    Since the birth of Dolly (the cloned sheep) in 1997, debates have arisen on the ethical and legal questions of cloning-for-biomedical-research (more commonly termed "therapeutic cloning") and of reproductive cloning using human gametes. Hong Kong enacted the Human Reproductive Technology Ordinance (Cap 561) in 2000. Section 15(1)(e) of this Ordinance prohibits the "replacing of the nucleus of a cell of an embryo with a nucleus taken from any other cell," i.e., nucleus substitution. Section 15(1)(f) prohibits the cloning of any embryo. The scope of the latter, therefore, is arguably the widest, prohibiting all cloning techniques such as cell nucleus replacement, embryo splitting, parthenogenesis, and cloning using stem cell lines. Although the Human Reproductive Technology Ordinance is not yet fully operative, this article examines how these prohibitions may adversely impact on basic research and the vision of the Hong Kong scientific community. It concludes that in light of recent scientific developments, it is time to review if the law offers a coherent set of policies in this area.

  10. The unexpected effect of PEGylated gold nanoparticles on the primary function of erythrocytes

    Science.gov (United States)

    He, Zeng; Liu, Jiaxin; Du, Libo

    2014-07-01

    Polyethylene glycol-functionalized gold nanoparticles (PEGylated AuNPs) have been widely used as nanocarriers for the delivery of various drugs. However, little attention has been paid to whether the PEGylated AuNPs could affect the primary function of human erythrocytes, which is the main cellular component in the blood. In the current study, we show that both the deformability and oxygen-delivering ability of erythrocytes are decreased when treated with PEGyalted AuNPs of various sizes, which can be attributed to the interaction between PEGylated AuNPs and erythrocyte membranes. It is observed that the PEGylated AuNPs could also induce the aggregation of band-3 and the ATP decrease of erythrocytes. In addition, the PEGylated AuNPs can accelerate the loss of CD47 on erythrocyte membranes, possibly enhancing the senescent process of erythrocytes and the following clearance by SIRPα-expressing leukocytes in bloodstream. The results suggested that PEGylated AuNPs have the potential to affect the primary function of human erythrocytes, which should be considered when using them as drug carriers.Polyethylene glycol-functionalized gold nanoparticles (PEGylated AuNPs) have been widely used as nanocarriers for the delivery of various drugs. However, little attention has been paid to whether the PEGylated AuNPs could affect the primary function of human erythrocytes, which is the main cellular component in the blood. In the current study, we show that both the deformability and oxygen-delivering ability of erythrocytes are decreased when treated with PEGyalted AuNPs of various sizes, which can be attributed to the interaction between PEGylated AuNPs and erythrocyte membranes. It is observed that the PEGylated AuNPs could also induce the aggregation of band-3 and the ATP decrease of erythrocytes. In addition, the PEGylated AuNPs can accelerate the loss of CD47 on erythrocyte membranes, possibly enhancing the senescent process of erythrocytes and the following clearance by

  11. [Morphofunctional and biochemical properties of erythrocytes in early postnatal ontogenesis in rats in norm and after prenatal stress].

    Science.gov (United States)

    Golubeva, E K; Nazarov, S B; Tomilova, I K

    2011-07-01

    Morphofunctional and biochemical properties of erythrocyte membrane were investigated in early postnatal ontogenesis in rats in norm and after prenatal immobilization stress. The transient decrease of erythrocyte membranes stability was revealed in the control rats. The ability to erythrocyte transformation and the concentration of lipid peroxidation products are increased. It has been shown by an increase of percentage discocytes and lower lipid peroxidation level that the erythrocyte membrane of the rats after prenatal stress is more stable.

  12. Serial cloning of pigs by somatic cell nuclear transfer: restoration of phenotypic normality during serial cloning.

    Science.gov (United States)

    Cho, Seong-Keun; Kim, Jae-Hwan; Park, Jong-Yi; Choi, Yun-Jung; Bang, Jae-Il; Hwang, Kyu-Chan; Cho, Eun-Jeong; Sohn, Sea-Hwan; Uhm, Sang Jun; Koo, Deog-Bon; Lee, Kyung-Kwang; Kim, Teoan; Kim, Jin-Hoi

    2007-12-01

    Somatic cell nuclear transfer (scNT) is a useful way to create cloned animals. However, scNT clones exhibit high levels of phenotypic instability. This instability may be due to epigenetic reprogramming and/or genomic damage in the donor cells. To test this, we produced transgenic pig fibroblasts harboring the truncated human thrombopoietin (hTPO) gene and used them as donor cells in scNT to produce first-generation (G1) cloned piglets. In this study, 2,818 scNT embryos were transferred to 11 recipients and five G1 piglets were obtained. Among them, a clone had a dimorphic facial appearance with severe hypertelorism and a broad prominent nasal bridge. The other clones looked normal. Second-generation (G2) scNT piglets were then produced using ear cells from a G1 piglet that had an abnormal nose phenotype. We reasoned that, if the phenotypic abnormality of the G1 clone was not present in the G2 and third-generation (G3) clones, or was absent in the G2 clones but reappeared in the G3 clones, the phenotypic instability of the G1 clone could be attributed to faulty epigenetic reprogramming rather than to inherent/accidental genomic damage to the donor cells. Blastocyst rates, cell numbers in blastocyst, pregnancy rates, term placenta weight and ponderal index, and birth weight between G1 and G2 clones did not differ, but were significantly (P clones and could not find any significant differences in the methylation patterns between G1 and G2 clones. Indeed, we failed to detect the phenotypic abnormality in the G2 and G3 clones. Thus, the phenotypic abnormality of the G1 clone is likely to be due to epigenetic dysregulation. Additional observations then suggested that expression of the hTPO gene in the transgenic clones did not appear to be the cause of the phenotypic abnormality in the G1 clones and that the abnormality was acquired by only a few of the G1 clone's cells during its gestational development. 2007 Wiley-Liss, Inc

  13. Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract.

    Science.gov (United States)

    Okoko, Tebekeme; Ere, Diepreye

    2012-06-01

    To investigate the in vitro antioxidant potential of Carica papaya (C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation. Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract (at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage. Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities using in vitro models in a concentration dependent manner (Ppapaya leaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy. Thus, the leaves can be exploited for pharmaceutical and nutritional purposes.

  14. Impaired erythrocyte filterability of spontaneously hypertensive rats: investigation by nickel filtration technique.

    Science.gov (United States)

    Ariyoshi, Kyoko; Maruyama, Toru; Odashiro, Keita; Akashi, Koichi; Fujino, Takehiko; Uyesaka, Nobuhiro

    2010-01-01

    Deformability of erythrocytes plays a key role in the impairment of the microcirculation in hypertension. However, erythrocyte deformability in spontaneously hypertensive rats (SHR) during development of hypertension has not been fully investigated so far. Erythrocyte filterability (whole cell deformability) was investigated in relation to blood pressure measured by the tail-cuff method in SHR and age-matched Wistar-Kyoto rats (WKY), using a highly sensitive and reproducible nickel mesh filtration technique. Impaired erythrocyte filterability was marked (37.0+/-17.5%) in prehypertensive young SHR (7 weeks of age) and sustained (51.6+/-13.3%) in hypertensive mature SHR (18 weeks of age), when compared with that of age-matched WKY (62.1+/-7.2% in 7 weeks of age, Perythrocytes, but the erythrocyte count was significantly (Perythrocyte filterability in SHR is considered to contribute to the development and maintenance of genetic hypertension. (Circ J 2010; 74: 129 - 136).

  15. The effects of superoxide dismutase knockout on the oxidative stress parameters and survival of mouse erythrocytes.

    Science.gov (United States)

    Grzelak, Agnieszka; Kruszewski, Marcin; Macierzyńska, Ewa; Piotrowski, Łukasz; Pułaski, Łukasz; Rychlik, Błazej; Bartosz, Grzegorz

    2009-01-01

    The erythrocytes of 12-month old Sod1 (-/-) mice showed an increased level of reactive oxygen species (ROS), as estimated by the degree of dihydroethidine and dihydrorhodamine oxidation, and the increased level of Heinz bodies. No indices of severe oxidative stress were found in the red blood cells and blood plasma of Sod1 (-/-) mice as judged from the lack of significant changes in the levels of erythrocyte and plasma glutathione, plasma protein thiol and carbonyl groups and thiobarbituric-acid reactive substances in the blood plasma. However, a decreased erythrocyte lifespan, increased reticulocyte count and splenomegaly were noted, indicating the importance of superoxide dismutase for maintaining erythrocyte viability. The levels of erythrocyte ROS and Heinz bodies and the reticulocyte count were indistinguishable in Sod1 (+/+) and Sod1 (+/-) mice, suggesting that a superoxide dismutase activity decrease to half of its normal value may be sufficient to secure the protective effects of the enzyme.

  16. A rapid method for counting nucleated erythrocytes on stained blood smears by digital image analysis

    Science.gov (United States)

    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.

  17. Hemolitic action of Naja naja atra cardiotoxin on erythrocytes from different animals

    Directory of Open Access Journals (Sweden)

    J. C. Troiano

    2006-01-01

    Full Text Available A comparative study on the sensitivity of erythrocytes from different vertebrate species (avian, mammalian and reptilian to the hemolytic action caused by cardiotoxin isolated from Naja naja atra venom was carried out. Cardiotoxin was able to induce direct hemolysis in washed erythrocytes from several animals, except for llama. The EC50 values from hemolysis of the most sensitive (cat and the most resistant (snake animal varied approximately tenfold. According to the cell behavior, it was possible to characterize four types of behavior: The first was observed in cat, horse and human cells; the second in rat, rabbit and dog erythrocytes; and the third only in llama erythrocytes, which were resistant to cardiotoxin concentrations up to 300 µg/ml. Finally, avian and reptilian erythrocytes were more resistant to cardiotoxin III-induced hemolysis than those of the mammalian species.

  18. [Effects of acute hypervolemic hemodilution and intraoperative blood salvage on erythrocyte morphology and biomechanics].

    Science.gov (United States)

    Zhang, Yiwen; Xinh, Zumin; Guo, Qiang; He, Zhongcheng

    2015-07-01

    To investigate the effects of acute hypervolemic hemodilution (AHH) and intraoperative blood salvage (IOBS) on the morphology and biomechanics of erythrocytes using atomic force microscopy (AFM). Blood samples were collected from 20 patients undergoing orthopedic surgery before operation (T1), immediately after AHH (T2), and after blood salvage (T3). AFM at nanometer resolution was used to examine the morphology and biomechanics of the collected erythrocytes. The blood samples collected at T1 showed a significantly lower ratio of heteromorphous erythrocytes than those collected at T2 and T3 [(2.6∓1.3)% vs (19.3∓1.6)% and (17.6∓1.4)%, Pbiomechanics of the single erythrocyte in salvaged blood and blood after AHH compared with those of venous blood. AHH and IOBS may cause significant changes in the morphology and biomechanics of erythrocytes in the salvaged blood.

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

    Science.gov (United States)

    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. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Simplified cryopreservation of porcine cloned blastocysts

    DEFF Research Database (Denmark)

    Du, Yutao; Zhang, Yunhai; Li, Juan

    2007-01-01

    )â€"handmade cloning (HMC)â€"to establish a simplified and efficient cryopreservation system for porcine cloned embryos. In Experiment 1, zonae pellucidae of oocytes were partially digested with pronase, followed by centrifugation to polarize lipid particles. Ninety percent (173/192) oocytes were successfully......). Our results prove that porcine embryos produced from delipated oocytes by PA or HMC can be cryopreserved effectively by ultrarapid vitrification. Further experiments are required to assess the in vivo developmental competence of the cloned-vitrified embryos  ...

  1. Alterations of erythrocyte rheology and cellular susceptibility in end stage renal disease: Effects of peritoneal dialysis.

    Directory of Open Access Journals (Sweden)

    Nesrin Zeynep Ertan

    Full Text Available In this study, we investigated the effects of peritoneal dialysis on hemorheological and hematological parameters and their relations with oxidant and antioxidant status of uremic patients. Hemorheological parameters (erythrocyte deformability, erythrocyte aggregation, osmotic deformability, blood and plasma viscosity were measured in patients with renal insufficiency undergoing peritoneal dialysis (PD and volunteers. Erythrocyte deformability, osmotic deformability and aggregation in both autologous plasma and 3% dextran 70 were measured by laser diffraction ektacytometry. Enzyme activities of glutathione peroxidase, superoxide dismutase and catalase were studied in erythrocytes; lipid peroxidation was studied by measuring the amount of malondialdehyde in both erythrocytes and plasma samples. Blood viscosity at native hematocrit was significantly lower in PD patients at all measured shear rates compared to controls, but it was high in PD patients at corrected (45% hematocrit. Erythrocyte deformability did not show any difference between the two groups. Osmotic deformability was significantly lower in PD patients compared to controls. Aggregation index values were significantly high in PD patients in plasma Catalase and glutathione peroxidase activities in erythrocytes were decreased in PD patients whereas superoxide dismutase activity was increased compared to controls. Malondialdehyde was significantly increased in erythrocytes and plasma samples of PD patients which also shows correlations with aggregation parameters. It has been concluded that erythrocytes in PD patients are more prone to aggregation and this tendency could be influenced by lipid peroxidation activity in patient's plasma. These results imply that uremic conditions, loss of plasma proteins and an increased risk of oxidative stress because of decreasing levels of antioxidant enzymes affect erythrocyte rheology during peritoneal dialysis. This level of distortion may have

  2. Age sensitivity of NFkappaB abundance and programmed cell death in erythrocytes induced by NFkappaB inhibitors

    NARCIS (Netherlands)

    Ghashghaeinia, M.; Cluitmans, J.C.A.; Toulany, M.; Saki, M.; Koberle, M.; Lang, E.; Dreischer, P.; Biedermann, T.; Duszenko, M.; Lang, F.; Bosman, G.J.C.G.M.; Wieder, T.

    2013-01-01

    BACKGROUND/AIMS: Erythrocytes may enter eryptosis, a suicidal death characterized by cell shrinkage and phosphatidylserine exposure at the erythrocyte outer membrane. Susceptibility to eryptosis is enhanced in aged erythrocytes and stimulated by NFkappaB-inhibitors Bay 11-7082 and parthenolide. Here

  3. Hierarchical, domain type-specific acquisition of antibodies to Plasmodium falciparum erythrocyte membrane protein 1 in Tanzanian children

    DEFF Research Database (Denmark)

    Cham, Gerald K K; Turner, Louise; Kurtis, Jonathan D

    2010-01-01

    Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a variant antigen expressed on the surface of malaria-infected erythrocytes. PfEMP1 attaches to the vascular lining and allows infected erythrocytes to avoid filtration through the spleen. Each parasite genome encodes about 60...

  4. var gene transcription and PfEMP1 expression in the rosetting and cytoadhesive Plasmodium falciparum clone FCR3S1.2

    OpenAIRE

    Chen Qijun; Normark Johan; Blomqvist Karin; Moll Kirsten; Albrecht Letusa; Wahlgren Mats

    2011-01-01

    Abstract Background The pathogenicity of Plasmodium falciparum is in part due to the ability of the parasitized red blood cell (pRBC) to adhere to intra-vascular host cell receptors and serum-proteins. Binding of the pRBC is mediated by Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), a large multi-variant molecule encoded by a family of ≈60 var genes. Methods The study of var gene transcription in the parasite clone FCR3S1.2 was performed by semi-quantitative PCR and quantitati...

  5. [Cloning and expression of alpha-D-galactosidase from coffee bean (Coffea liberica & Coffea canephora)].

    Science.gov (United States)

    Liang, Su-Yu; Zheng, Xue-Qin

    2005-09-01

    Alpha-D-galactosidase (alpha-Gal,E.C. 3.2.1.22) is an exo-glycosidase. The enzyme isolated from coffee beans has been well characterized. It has high activity in hydrolyzing the terminal alpha-D-galactoside residues from glycoconjugates on human blood group B erythrocytes, as well as in converting the blood group B into O. A different 1089 bp cDNA open reading frame(ORF) encoding Gal of Coffea liberica & C. canephora was cloned by homology-based RT-PCR. The cloned Gal most closely resembles the corresponding one from C. aribica (98.7% and 99.27% identity). Heterologous overexpression of the two 1.1 kb cDNA fragments was obtained by using one Pichia pastoris stain GS115 and two secret expression vectors, pPICZalphaA and pGAPZalphaA. The expressed protein from P. pastoris stain GS115 was concentrated by ammonium sulfate precipitation and SDS-PAGE assay showed a clear band in the gel. The highest activity of the recombinant enzyme was up to 48.22 U/mL.

  6. Human cloning and the myth of disenchantment

    National Research Council Canada - National Science Library

    Laurențiu, Staicu

    2012-01-01

    This study has a twofold objective: firstly, it aims to examine the main types of argument that have been formulated against human cloning, to identify their presuppositions and to evaluate their strength...

  7. Cloning and molecular characterization of glyceraldehyde-3 ...

    African Journals Online (AJOL)

    Cloning and molecular characterization of glyceraldehyde-3-phosphate dehydrogenase gene from thermotolerant mushroom, Lentinus polychrous. ... sequence of the L. polychrous GAPDH-encoded protein shared significant sequence identity with other GAPDH proteins from basidiomycetes. Phylogenetic analysis ...

  8. DNA microarrays : a molecular cloning manual

    National Research Council Canada - National Science Library

    Sambrook, Joseph; Bowtell, David

    2002-01-01

    .... This manual, designed to extend and to complement the information in the best-selling Molecular Cloning, is a synthesis of the expertise and experience of more than 30 contributors all innovators in a fast moving field...

  9. Cloning and characterization of new bioluminescent proteins

    Science.gov (United States)

    Szent-Gyorgyi, Christopher; Ballou, Byron T.; Dagnal, Erich; Bryan, Bruce

    1999-07-01

    Over the past two years Prolume has undertaken a comprehensive program to clone luciferases and associated 'green fluorescent proteins' (GFPs) from marine animals that use coelenterazine as the luciferin. To data we have cloned several bioluminescent proteins, including two novel copepod luciferases and two anthozoan GFPs. These four proteins have sequences that differ greatly form previously cloned analogous proteins; the sequence diversity apparently is due to independent evolutionary origins and unusual evolutionary constraints. Thus coelenterazine-based bioluminescent systems may also manifest a variety of useful properties. We discuss form this taxonomic perspective the initial biochemical and spectral characterization of our cloned proteins. Emphasis is placed on the anthozoan luciferase-GFP systems, whose efficient resonance energy transfer has elicited much current interest.

  10. Meat and Milk Compositions of Bovine Clones

    National Research Council Canada - National Science Library

    X. Cindy Tian; Chikara Kubota; Kunihito Sakashita; Yoshiaki Izaike; Ryoichi Okano; Norio Tabara; Carol Curchoe; Lavina Jacob; Yuqin Zhang; Sadie Smith; Charles Bormann; Jie Xu; Masumi Sato; Sheila Andrew; Xiangzhong Yang; R. Michael Roberts

    2005-01-01

    ...? Here, we provide data on >100 parameters that compare the composition of meat and milk from beef and dairy cattle derived from cloning to those of genetic- and breed-matched control animals from conventional reproduction...

  11. Endangered wolves cloned from adult somatic cells.

    Science.gov (United States)

    Kim, Min Kyu; Jang, Goo; Oh, Hyun Ju; Yuda, Fibrianto; Kim, Hye Jin; Hwang, Woo Suk; Hossein, Mohammad Shamim; Kim, Joung Joo; Shin, Nam Shik; Kang, Sung Keun; Lee, Byeong Chun

    2007-01-01

    Over the world, canine species, including the gray wolf, have been gradually endangered or extinct. Many efforts have been made to recover and conserve these canids. The aim of this study was to produce the endangered gray wolf with somatic cell nuclear transfer (SCNT) for conservation. Adult ear fibroblasts from a female gray wolf (Canis lupus) were isolated and cultured in vitro as donor cells. Because of limitations in obtaining gray wolf matured oocytes, in vivo matured canine oocytes obtained by flushing the oviducts from the isthmus to the infundibulum were used. After removing the cumulus cells, the oocyte was enucleated, microinjected, fused with a donor cell, and activated. The reconstructed cloned wolf embryos were transferred into the oviducts of the naturally synchronized surrogate mothers. Two pregnancies were detected by ultrasonography at 23 days of gestation in recipient dogs. In each surrogate dog, two fetal sacs were confirmed by early pregnancy diagnosis at 23 days, but only two cloned wolves were delivered. The first cloned wolf was delivered by cesarean section on October 18, 2005, 60 days after embryo transfer. The second cloned wolf was delivered on October 26, 2005, at 61 days postembryo transfer. Microsatellite analysis was performed with genomic DNA from the donor wolf, the two cloned wolves, and the two surrogate female recipients to confirm the genetic identity of the cloned wolves. Analysis of 19 microsatellite loci confirmed that the cloned wolves were genetically identical to the donor wolf. In conclusion, we demonstrated live birth of two cloned gray wolves by nuclear transfer of wolf somatic cells into enucleated canine oocyte, indicating that SCNT is a practical approach for conserving endangered canids.

  12. Influence of iodine-containing radiographic contrast media on the phenotype of erythrocytes from different laboratory animal species.

    Science.gov (United States)

    Hiebl, B; Hopperdietzel, C; Hünigen, H; Dietze, K; Klein, S; Schreier, B; Jung, F

    2013-01-01

    It is well known that clinically relevant concentrations of iodine-containing radiographic contrast media (CM) induce morphological changes in human erythrocytes. However, there are only few reports about CM effects on erythrocytes of animals (e.g. mice, rats, rabbits, and pigs). Thus, two conventional iodine-containing CM (iodixanol, Visipaque™ 320; iomeprol, Iomeprol™ 350) were tested for their effects on the morphology of erythrocytes from these. After venous blood sampling and blood centrifugation, the autologous plasma was supplemented with 40 vol% CM. Then, a defined number of erythrocytes was incubated in this CM-supplemented plasma for 5 min at body temperature (37°C). Subsequently, 10 μL of the cell suspension were transferred to a purified glass slide and the number of discocytes, echinocytes, and acanthocytes was counted within a total number of 100 erythrocytes (40 fold primary magnification, transmitted light mode). Shape changes of the erythrocytes from all animal species strongly depended on the type of CM and compared to the effects which have already been described for human erythrocytes. Incubation in both CM resulted in morphological changes of the erythrocytes. Incubation in a iodixanol/plasma mixture induced the lowest echinocyte or acanthocyte formation. Porcine erythrocytes showed a much more distinct shape change than those of other animal species and humans. These results suggest erythrocytes from mice, rats, and rabbits are a suitable model system for a model system for human erythrocytes when CM effects on the cellular shape of erythrocytes have to be tested. The distinct deformation of the pig erythrocytes could be due to differences in the pig erythrocyte membrane or the physical and chemical constitution of pig erythrocytes.

  13. Emotional reactions to human reproductive cloning.

    Science.gov (United States)

    May, Joshua

    2016-01-01

    Extant surveys of people's attitudes towards human reproductive cloning focus on moral judgements alone, not emotional reactions or sentiments. This is especially important given that some (especially Leon Kass) have argued against such cloning on the ground that it engenders widespread negative emotions, like disgust, that provide a moral guide. To provide some data on emotional reactions to human cloning, with a focus on repugnance, given its prominence in the literature. This brief mixed-method study measures the self-reported attitudes and emotions (positive or negative) towards cloning from a sample of participants in the USA. Most participants condemned cloning as immoral and said it should be illegal. The most commonly reported positive sentiment was by far interest/curiosity. Negative emotions were much more varied, but anxiety was the most common. Only about a third of participants selected disgust or repugnance as something they felt, and an even smaller portion had this emotion come to mind prior to seeing a list of options. Participants felt primarily interested and anxious about human reproductive cloning. They did not primarily feel disgust or repugnance. This provides initial empirical evidence that such a reaction is not appropriately widespread. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  14. Reproductive cloning combined with genetic modification.

    Science.gov (United States)

    Strong, C

    2005-11-01

    Although there is widespread opposition to reproductive cloning, some have argued that its use by infertile couples to have genetically related children would be ethically justifiable. Others have suggested that lesbian or gay couples might wish to use cloning to have genetically related children. Most of the main objections to human reproductive cloning are based on the child's lack of unique nuclear DNA. In the future, it may be possible safely to create children using cloning combined with genetic modifications, so that they have unique nuclear DNA. The genetic modifications could be aimed at giving such children genetic characteristics of both members of the couple concerned. Thus, cloning combined with genetic modification could be appealing to infertile, lesbian, or gay couples who seek genetically related children who have genetic characteristics of both members. In such scenarios, the various objections to human reproductive cloning that are based on the lack of genetic uniqueness would no longer be applicable. The author argues that it would be ethically justifiable for such couples to create children in this manner, assuming these techniques could be used safely.

  15. CloneAssistant 1.0: a stand-alone software for automated cloning primer design.

    Science.gov (United States)

    Shao, Chaogang; Meng, Yijun; Lv, Shaolei; Zhong, Wei; Wang, Zheyu; Chen, Ming

    2010-11-01

    "CloneAssistant 1.0" is a stand-alone software compatible with the current Windows operating systems, which can automatically design cloning primers with full consideration of the sequence information of vectors and genes, cloning strategies, the principles of primer design, reading frames, position effects, and enzymatic reaction conditions for users. Five internal XML (extensible markup language) databases [restriction enzymes, plasmids, universal buffers, PCR (polymerase chain reaction) protection bases, and an MCS (multiple cloning site) double digest interference database] were established to serve as the basic support for "CloneAssistant 1.0". The primer pairs designed are sorted according to the difficulty of the follow-up experiments. Once a primer pair is selected by the user, detailed experimental guidance for this primer pair will be provided. In addition, "CloneAssistant 1.0" can be used for restriction map analysis, ORF (open reading frame) finding, sequence alignment and complementary analysis, translation, restriction enzyme and universal buffer queries, and isocaudamer analysis. "CloneAssistant 1.0" makes gene clone design much easier, and it can be freely downloaded from http://bis.zju.edu.cn/clone. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Birth of viable puppies derived from breeding cloned female dogs with a cloned male.

    Science.gov (United States)

    Park, J E; Hong, S G; Kang, J T; Oh, H J; Kim, M K; Kim, M J; Kim, H J; Kim, D Y; Jang, G; Lee, B C

    2009-09-15

    Since the establishment of production of viable cloned dogs by somatic cell nucleus transfer, great concern has been given to the reproductive abilities of these animals (Canis familiaris). Therefore, we investigated reproductive activity of cloned dogs by (1) performing sperm analysis using computer-assisted sperm analysis and early embryonic development, (2) assessing reproductive cycling by measuring serum progesterone (P4) levels and performing vaginal cytology, and (3) breeding cloned dogs using artificial insemination. Results showed that most parameters of sperm motility in a cloned male dog were within the reference range, and in vivo-matured oocytes from a noncloned female were successfully fertilized by spermatozoa from a cloned male dog and develop normally to the 8-cell stage. Three cloned female dogs displayed normal patterns of P4 levels and morphologic changes of the vaginal epithelium. Two cloned female dogs became pregnant using semen from a cloned male dog and successfully delivered 10 puppies by natural labor. In conclusion, these data demonstrated that both cloned male and female dogs are fertile, and their puppies are currently alive and healthy with normal growth patterns.

  17. Do Clones Dream of Love? Images of Clones in Popular Culture

    Directory of Open Access Journals (Sweden)

    Dragana Antonijević

    2016-02-01

    Full Text Available Fantasies about clones, cyborgs and androids have become part and parcel of the mythology of modern times – the mythologies of the biotechnological era in which the achievements of genetic engineering have inflamed fears of possible abuse of scientific knowledge and the consequences of such abuse. The paper considers the phenomenon of reproductive cloning of human beings as it is represented in popular culture, especially film as it is one of the most important sources of representations and constructions of ideas about clones. After the introductory consideration of this phenomenon in scientific, ethical and media debates which are imbued with rejection of reproductive cloning, I have analyzed the different uses of the clone motif in selected movies. I have examined the structure and content of the genre formula of "social melodrama" which is present in films about clones, and have analyzed the mythical patterns pertaining to the topic of cloning, such as the myth of immortality, the myth of twins, the myth of the uniqueness of human kind etc. Ultimately, the nature and origins of the fear of clones and disgust that clones cause have been examined, and it has been shown that they mostly boil down to the fear of the dehumanization of human beings, the fear of the loss of difference and the transgression of biological, sociocultural and metaphysical boundaries.

  18. A GBP 130 derived peptide from Plasmodium falciparum binds to human erythrocytes and inhibits merozoite invasion in vitro

    Directory of Open Access Journals (Sweden)

    Jorge E Suarez

    2000-08-01

    Full Text Available The malarial GBP 130 protein binds weakly to intact human erythrocytes; the binding sites seem to be located in the repeat region and this region's antibodies block the merozoite invasion. A peptide from this region (residues from 701 to 720 which binds to human erythrocytes was identified. This peptide named 2220 did not bind to sialic acid; the binding site on human erythrocyte was affected by treatment with trypsin but not by chymotrypsin. The peptide was able to inhibit Plasmodium falciparum merozoite invasion of erythrocytes. The residues F701, K703, L705, T706, E713 (FYKILTNTDPNDEVERDNAD were found to be critical for peptide binding to erythrocytes.

  19. Influence of suspension osmolarity and erythrocyte volume on cell deformability

    Energy Technology Data Exchange (ETDEWEB)

    Feo, C. (Institut de Pathologie Cellulaire, INSERM, 94 - Kremlin-Bicetre (France)); Phillips, W.M. (School of Mechanical Engineering, Purdue University, West Lafayette, IN (USA))

    1982-01-01

    Erythrocytes were suspended in dextran solutions of phosphate buffered saline with solution osmolarities from 400 to 20 mosM/kg. The dilute suspensions were subjected to linear shear and their deformation determined by laser diffractometry (Ektacytometer). Cell volumes were measured using a Coulter counter following fixation in glutaraldehyde to eliminate the influence of deformability on the volume measurement. Minimum deformability generally agreed with the maximum cellular volume produced by hypotonic solutions. However, reduced deformability was observed for both hyperosmotic and hypoosmotic conditions. The oncotic effect of the dextran delayed hemolysis to surprisingly low values of solution osmolarity. In contrast with the usual osmotic fragility results, in the hypotonic dextran solutions there was no evidence of hemoglobin release. At low shear stresses, deformability was found to be enhanced by reducing intracellular viscosity (via osmotic water transport into the cell). However, the maximum cellular deformation obtained at high shear stress was always less than for the normal discocyte at normal osmolarities.

  20. Clinical relevance of erythrocyte ferritin in microcytic anemias.

    Science.gov (United States)

    Vagace, Jose M; Peças, Antonio; Groiss, Jorge; Bento, Celeste; Ribeiro, Maria Leticia; Gervasini, Guillermo

    2015-03-10

    Erythrocyte ferritin (EF) reflects the balance between iron supply and its utilization for hemoglobin synthesis. This balance is altered in microcytosis. We aimed to evaluate the diagnostic value of both EF and the ratio (FRR) plasma ferritin (PF)/EF in these disorders. A total of 231 subjects participated in the study. Samples from 93 adult patients with different causes of microcytosis, 57 healthy subjects and 81 full-term newborns were analyzed to determine EF and PF concentrations and other hematological parameters. In patients with iron deficiency, and in contrast to PF, EF decreased only in the presence of anemia and in direct correlation with the degree of microcytosis (Pearson's panemia of inflammation than in those with thalassemia (p<10e-5), thus helping to discriminate between these disorders. EF and FRR are tools that may be useful in the diagnosis of the main causes of microcytosis. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Mechanisms and pathophysiological significance of eryptosis, the suicidal erythrocyte death.

    Science.gov (United States)

    Lang, Elisabeth; Lang, Florian

    2015-03-01

    Eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and cell membrane scrambling, is stimulated by Ca(2+) entry through Ca(2+)-permeable, PGE2-activated cation channels, by ceramide, caspases, calpain, complement, hyperosmotic shock, energy depletion, oxidative stress, and deranged activity of several kinases (e.g. AMPK, GK, PAK2, CK1α, JAK3, PKC, p38-MAPK). Eryptosis is triggered by intoxication, malignancy, hepatic failure, diabetes, chronic renal insufficiency, hemolytic uremic syndrome, dehydration, phosphate depletion, fever, sepsis, mycoplasma infection, malaria, iron deficiency, sickle cell anemia, thalassemia, glucose 6-phosphate dehydrogenase deficiency, and Wilson's disease. Eryptosis may precede and protect against hemolysis but by the same token result in anemia and deranged microcirculation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. A Combined Numerical and Experimental Analysis on Erythrocyte Damage Mechanism in Microscale Flow

    Directory of Open Access Journals (Sweden)

    Di Zhang

    2013-01-01

    Full Text Available An experimental system was designed and completed to realize the visualization of erythrocyte suspension microscale flow in microchannel and obtain the geometric parameters. The numerical simulation of the flow in the microchannel was accomplished to obtain the distribution of the physical parameters. Combined with the experimental data, the fitted curves of the physical parameters and geometric parameters on the axis were achieved. By analyzing the energy balance of the erythrocyte, the curve of the elasticity modulus of the erythrocyte membrane was obtained. The mechanism of the hemolysis caused by collision was expounded. Besides, the comparison among different cases was completed, illustrating the influence of the flow rate on hemolysis. The result shows that the predominant force of longitudinal compression is the pressure difference per erythrocyte. The curve of the elasticity modulus indicates that the membrane elasticity rapidly decreases as the erythrocyte approaches to the wall. The erythrocyte membrane loses elasticity, indicating that the contractile protein is fragile to the compressive loading, which increases significantly with a higher flow rate, making the erythrocyte membrane more likely to fracture.

  3. In vitro erythrocyte oxidative damage of Morinda citrifolia L (noni leaves extract

    Directory of Open Access Journals (Sweden)

    Alicia Lagarto

    2013-06-01

    Full Text Available Slight decrease of hemoglobin and erythrocyte count was observed previously after subchronic oral dosing of Morinda citrifolia L leaves extract in rats. Induction of erythrocyte membrane damage could be the cause for these effects. Aims: The objective of this investigation was to assess the in vitro cytotoxicity of Morinda citrifolia L leaves extract and fractions on rat erythrocytes. Methods: Hemolytic damage was assayed in rat erythrocytes. Oxidative stress was assessed by measuring methemoglobin formation, thiobarbituric acid reactive substances (TBARS and enzyme antioxidant activities, superoxide dismutase (SOD and catalase (CAT. Results: Morinda citrifolia L extract caused no hemolysis and induced oxidative damage to red cells in vitro. Methemoglobin increase was observed at concentration between 2 and 8 mg/ml of the extract. Lipid peroxidation was increased and CAT and SOD activities were depleted indicating a possible increase of hydrogen peroxide and superoxide radicals in erythrocytes. Ethyl acetate, dichloromethane and butanol fraction did not cause methemoglobin formation while water fraction increased methemoglobin level at doses up to 6 mg/ml. Conclusions: We concluded that high doses of Morinda citrifolia L extract promote erythrocyte oxidative damage due to metabolites present in water fraction. These could be the cause of decreased erythrocyte and hemoglobin levels observed. [J Intercult Ethnopharmacol 2013; 2(3.000: 135-140

  4. Nucleated Teleost Erythrocytes Play an Nk-Lysin- and Autophagy-Dependent Role in Antiviral Immunity

    Science.gov (United States)

    Pereiro, Patricia; Romero, Alejandro; Díaz-Rosales, Patricia; Estepa, Amparo; Figueras, Antonio; Novoa, Beatriz

    2017-01-01

    With the exception of mammals, vertebrate erythrocytes are nucleated. Nevertheless, these cells are usually considered as mere carriers of hemoglobin. In this work, however, we describe for the first time an unrecognized role of teleost red blood cells (RBCs). We found that Nk-lysin (Nkl), an antimicrobial peptide produced by NK-cells and cytotoxic T-lymphocytes, was also expressed in flatfish turbot (Scophthalmus maximus) erythrocytes. Although the antiviral role of Nkl remains to be elucidated, we found a positive correlation between the transcription of nkl and the resistance to an infection with Rhabdovirus in a teleost fish. Surprisingly, Nkl was found to be present in the autophagolysosomes of erythrocytes, and therefore this higher resistance provided by Nkl could be related to autophagy. The organelles of RBCs are degraded through autophagy during the maturation process of these cells. In this work, we observed that the blockage of autophagy increased the replication of viral hemorrhagic septicemia virus in nucleated teleost erythrocytes, which suggests that this mechanism may also be a key process in the defense against viruses in these cells. Nkl, which possesses membrane-perturbing ability and was affected by this modulation of RBC autophagy, could also participate in this process. For the first time, autophagy has been described not only as a life cycle event during the maturation of erythrocytes but also as a pivotal antiviral mechanism in nucleated erythrocytes. These results suggest a role of erythrocytes and Nkl in the antiviral immunity of fish and other vertebrates with nucleated RBCs. PMID:29163526

  5. The study of the dynamics of erythrocytes under the influence of an external electric field

    Science.gov (United States)

    Mamaeva, Sargylana N.; Maksimov, Georgy V.; Antonov, Stepan R.

    2017-11-01

    A mathematical model is considered for the determination of the surface charge of an erythrocyte with its shape approximated by a surface of revolution of the second order, and the investigation of the dynamics of erythrocytes under the influence of an external electric field. In the first part of this work, the electrical surface charge of the erythrocyte of the patient was calculated with the assumption that the change in the shape and size of the red blood cells leads to stabilization of the electric field, providing a normal electrostatic repulsion. In the second part of the work, the research results of dynamics of changes in the morphology of erythrocytes under the influence of an external electric field depending on the values of their surface charge and resistance of blood plasma is presented. In the course of the work, the dependence of the surface charge of red blood cells from their shape and size is presented. The determination of the relationship between the value of the charge field and the surface of erythrocytes in norm and in pathology is shown. The dependence of the velocity of the erythrocytes on the characteristics of the external electric field, surface charge of the erythrocyte and properties of the medium is obtained. The results of this study can be applied indirectly to diagnose diseases and to develop recommendations for experimental studies of hemodynamics under the influence of various external physical factors.

  6. [Changes of physiological and biochemical characteristics of rat erythrocytes after blood loss].

    Science.gov (United States)

    Maslova, M N; Kazennov, A M; Katiukhin, L N; Novozhilov, A V; Skverchinskaia, E A; Tavrovskaia, T V

    2007-01-01

    In experiments of Wistar male rats, changes are studied of erythrocyte hematological, biochemical (activitities of transport ATPases), and rheological properties (capability for aggregation and deformability) 7 days after bloodletting of 12-15 % of the total blood mass. It has been shown that alongside with an elevation of erythrocyte volume and of the number of immature cells - reticulocytes, there was a statistically significant increase of Na,K-ATPase and Ca-ATPase activities in the whole erythrocytes and their membrane preparations - ghosts, the increment of activity in the case of Na,K-ATPase being essentially higher in the whole cells. This indicates the appearance of an enzyme activator inside the erythrocytes. There are also revealed a decrease of firmness of erythrocyte aggregates, a deceleration of spontaneous aggregation, and an increase of index of erythrocyte deformability. The conclusion is made that changes of erythrocyte rheological properties are interconnected with changes of the Na,K-ATPase activity and are directed to optimization of blood circulation in large vessels and capillary network.

  7. Hepatic confinement of newly produced erythrocytes caused by low-temperature exposure in Xenopus laevis.

    Science.gov (United States)

    Maekawa, Shun; Iemura, Hitomi; Kuramochi, Yuko; Nogawa-Kosaka, Nami; Nishikawa, Hironori; Okui, Takehito; Aizawa, Youichi; Kato, Takashi

    2012-09-01

    Diminished erythrocyte count and erythropoiesis have been reported during hypothermia in some ectothermic animals. In this study, the African clawed frog, Xenopus laevis, was used to investigate the cause of hypothermia-induced anemia. We developed a new model of hypothermia at 5°C and monitored blood cell count and erythropoiesis on several days. Erythrocyte count declined by 30% on the first day following cold exposure (5°C) and mRNA expression of hemeoxygenase-1 was enhanced 10-fold; accumulation of iron as a result of heme degradation was observed in the liver. One day after low-temperature exposure, erythropoietin mRNA expression was elevated in the liver and lung compared with that at normal temperature (22°C) by qRT-PCR analysis. Examination of liver sections (i.e. the erythropoietic organ) showed an increase in o-dianisidine-positive erythrocytes in the hepatic sinusoid 5 days after the onset of low-temperature exposure compared with normal liver. Peripheral erythrocyte count remained low, indicating that newly produced erythrocytes did not migrate from the liver to the circulation during hypothermia. In conclusion, this study reveals hypothermic anemia as being associated with hepatic erythrocyte destruction; prolonged anemia during low-temperature exposure is concomitant with newly produced erythrocytes being confined to the liver and may lead to new insights into vertebrate hematopoiesis.

  8. Plasmodium falciparum acid basic repeat antigen (ABRA) peptides: erythrocyte binding and biological activity.

    Science.gov (United States)

    Curtidor, H; Urquiza, M; Suarez, J E; Rodriguez, L E; Ocampo, M; Puentes, A; Garcia, J E; Vera, R; Lopéz, R; Ramirez, L E; Pinzon, M; Patarroyo, M E

    2001-08-14

    Non overlapping 20-mer peptides, covering the complete sequence of acid basic repeat antigen (ABRA) of Plasmodium falciparum, were synthesised and tested in binding assays to erythrocytes. Five peptides localised in the N-terminal region coded 2148 (121LQSHKKLIKALKKNIESYQN(140)), 2149 (141KKHLIYKNKSYNPLLLSCVK(160)), 2150 (161KMNMLKENVDYIQKNQNLFK(180)), 2152 (201YKSQGHKKETSQNQNENNDN(220)) and 2153 (221QKYQEVNDEDDVNDEEDTND(240)) specifically bind to erythrocytes. These peptides bind independently of the peptide and erythrocyte charge, with high affinity (Kd between 70 and 180 nM) and the hydrophobic interaction is important for this binding ( approximately 30% hydrophobic critical residues). These results allow us define a specific erythrocyte binding region (residues 121-240), which may bound to at least three different binding sites on erythrocytes. Peptide 2153 shares the underlined sequence 221QKYQEVNDEDDVNDEEDTND(240) with an earlier 18-mer peptide recognised by human exposed sera. Peptides number 2148 and 2149 in vitro inhibit erythrocyte invasion by merozoites. We found that 2149 peptide and some of its glycine analogues show specific haemolytic and/or antimicrobial activity. We discuss a possible role of ABRA or its regions in the merozoite invasion of erythrocyte.

  9. Deoxygenation Affects Composition of Membrane-Bound Proteins in Human Erythrocytes

    Directory of Open Access Journals (Sweden)

    Oksana G. Luneva

    2016-06-01

    Full Text Available Background/Aims: ATP release from erythrocyte plays a key role in hypoxia-induced elevation of blood flow in systematic circulation. We have previously shown that hemolysis contributes to erythrocyte ATP release triggered by several stimuli, including hypoxia, but the molecular mechanisms of hypoxia-increased membrane fragility remain unknown. Methods: In this study, we compared the action of hypoxia on hemolysis, ATP release and the composition of membrane-bound proteins in human erythrocytes. Results: Twenty minutes incubation of human erythrocytes in the oxygen-free environment increased the content of extracellular hemoglobin by ∼1.5 fold. Paired measurements of hemoglobin and ATP content in the same samples, showed a positive correlation between hemolysis and ATP release. Comparative analysis of SDS-PAGE electrophoresis of erythrocyte ghosts obtained under control and deoxygenated conditions revealed a ∼2-fold elevation of the content of membrane-bound protein with Mr of ∼60 kDa. Conclusion: Deoxygenation of human erythrocytes affects composition of membrane-bound proteins. Additional experiments should be performed to identify the molecular origin of 60 kDa protein and its role in the attenuation of erythrocyte integrity and ATP release in hypoxic conditions.

  10. Identification of Babesia bigemina infected erythrocyte surface antigens containing epitopes conserved among strains.

    Science.gov (United States)

    Shompole, S; McElwain, T F; Jasmer, D P; Hines, S A; Katende, J; Musoke, A J; Rurangirwa, F R; McGuire, T C

    1994-03-01

    The presence of previously uncharacterized antigens (new antigens) on the surface of intact erythrocytes infected with three strains of Babesia bigemina from Kenya and one each from Puerto Rico, Mexico, St. Croix, and Texcoco-Mexico was demonstrated by indirect immunofluorescent antibody (IFA) reactions. These antigens were not strain specific because antibodies in bovine immune serum to either the Mexico or Kenya isolates reacted with all seven strains tested. Homologous and heterologous immune serum antibodies bound a maximum of 83% and 55%, respectively, of intact erythrocytes infected with the Kenya-Ngong strain but not uninfected erythrocytes. Both sera caused agglutination of only infected erythrocytes. Antibodies eluted from the surface of glutaraldehyde (0.25%) fixed infected erythrocytes had IFA reaction patterns among strains similar to those of immune sera before elution. Eluted antibodies were used to determine if these antigens were protein and encoded by B. bigemina. Eluted antibodies bound seven parasite-encoded proteins of 240, 220, 66, 62, 58, 52 and 38 kDa in an erythrocyte surface-specific immunoprecipitation reaction of 35S-methionine labelled proteins. It was concluded that the surface of B. bigemina infected erythrocytes had parasite-encoded proteins and that these proteins had surface exposed epitopes that were conserved among the seven strains examined which were from two continents.

  11. Hereditary spherocytosis and elliptocytosis associated with prosthetic heart valve replacement: rheological study of erythrocyte modifications.

    Science.gov (United States)

    Caprari, Patrizia; Tarzia, Anna; Mojoli, Giorgio; Cianciulli, Paolo; Mannella, Emilio; Martorana, Maria Cristina

    2009-04-01

    The implantation of a prosthetic heart valve (HVP) in patients with hereditary spherocytosis (HS) and hereditary elliptocytosis (HE) is rare, and the changes in the structure and deformability of erythrocytes that follow implantation in these patients have been poorly described. In the present study, the erythrocytes in HS and HE patients with mechanical HVP were compared to the erythrocytes in patients with only congenital membrane defects, in terms of biochemical modifications and rheological behaviour. Integral and cytoskeletal erythrocyte membrane proteins were studied, and blood viscosity (shear rate/shear stress ratio), aggregation ratio [eta(1 s(-1))/eta(200 s(-1))], and red cell visco-elasticity were determined. Valve replacement with a mechanical prosthesis worsened anaemia and resulted in a change in haemolysis, from sub-clinical to evident. The rheological investigation of erythrocytes from HS patients confirmed the characteristic increased viscosity and aggregation ratio and the decreased deformability. The rheological behaviour of erythrocytes from patients with HVP showed a decrease in viscosity and an increase in elastic modulus. In these patients, the prosthesis seems to have induced traumatic damage to the erythrocyte membrane, leading to fragmentation and lysis, which in turn modified rheological parameters. The biochemical and rheological investigation allowed us to understand the clinical and haematological pictures of the patients and to describe the role played by different factors in haemolytic anaemia.

  12. Nucleated Teleost Erythrocytes Play an Nk-Lysin- and Autophagy-Dependent Role in Antiviral Immunity.

    Science.gov (United States)

    Pereiro, Patricia; Romero, Alejandro; Díaz-Rosales, Patricia; Estepa, Amparo; Figueras, Antonio; Novoa, Beatriz

    2017-01-01

    With the exception of mammals, vertebrate erythrocytes are nucleated. Nevertheless, these cells are usually considered as mere carriers of hemoglobin. In this work, however, we describe for the first time an unrecognized role of teleost red blood cells (RBCs). We found that Nk-lysin (Nkl), an antimicrobial peptide produced by NK-cells and cytotoxic T-lymphocytes, was also expressed in flatfish turbot (Scophthalmus maximus) erythrocytes. Although the antiviral role of Nkl remains to be elucidated, we found a positive correlation between the transcription of nkl and the resistance to an infection with Rhabdovirus in a teleost fish. Surprisingly, Nkl was found to be present in the autophagolysosomes of erythrocytes, and therefore this higher resistance provided by Nkl could be related to autophagy. The organelles of RBCs are degraded through autophagy during the maturation process of these cells. In this work, we observed that the blockage of autophagy increased the replication of viral hemorrhagic septicemia virus in nucleated teleost erythrocytes, which suggests that this mechanism may also be a key process in the defense against viruses in these cells. Nkl, which possesses membrane-perturbing ability and was affected by this modulation of RBC autophagy, could also participate in this process. For the first time, autophagy has been described not only as a life cycle event during the maturation of erythrocytes but also as a pivotal antiviral mechanism in nucleated erythrocytes. These results suggest a role of erythrocytes and Nkl in the antiviral immunity of fish and other vertebrates with nucleated RBCs.

  13. THE IMPORTANCE OF THE ERYTHROCYTES OSMOTIC FRAGILITY TEST PERFORMED IN CHILDREN WITH INDIRECT HYPERBILIRUB1NEMIA

    Directory of Open Access Journals (Sweden)

    Ivana Stojanović

    2005-07-01

    Full Text Available The osmotic fragility test of erythrocytes is useful in the diagnosis of different types of hereditary hemolytic anemias followed with hyperbilirubinemia. Hemolytic anemias, characterized by accelerated destruction of red blood cells, are usually the consequence of many metabolic abnormalities like cellular membrane defect, erythrocyte enzymes defect or hemoglobin abnormalities – hemoglobinopathies. The object of our study was to assess the relationship between osmotic fragility test of erythrocytes and severity of indirect hyperbilirubinemia in some inherited erythrocytes’ disorders. We did the osmotic fragility test of erythrocytes by using Dacie, s method with normal values of erythrocytes hemolysis between 0,48 to 0,34% NaCl (minimal to maximal hemolysis. In hereditary spherocytosis, fragility of erythrocytes was increased (min. at 0,50 % NaCl to max. 0,44 % NaCl . In the child with β- thalassemia and cycle cell anemia erythrocytes fragility was decreased (min . at 0,42 to max. 0,32 % NaCl, that is 0,40% min. of hemolysis and 0,34% max. hemolysis in the second case. In newborn infants with high levels of indirect bilirubin in serum as a cause of physiological jaundice, the osmotic fragility test was within a normal range. Our findings point out the diagnostic value of osmotic fragility test in assessing patients with the indirect hyperbilirubinemia. This simple and important diagnostic test can be performed in small laboratories.

  14. Breakdown of Phosphatidylserine Asymmetry Following Treatment of Erythrocytes with Lumefantrine

    Directory of Open Access Journals (Sweden)

    Kousi Alzoubi

    2014-02-01

    Full Text Available Background: Lumefantrine, a commonly used antimalarial drug, inhibits hemozoin formation in parasites. Several other antimalarial substances counteract parasitemia by triggering suicidal death or eryptosis of infected erythrocytes. Eryptosis is characterized by cell shrinkage and cell membrane scrambling leading to phosphatidylserine-exposure at the erythrocyte surface. Signaling involved in eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i, formation of ceramide, oxidative stress and/or activation of p38 kinase, protein kinase C (PKC, or caspases. The present study explored, whether lumefantrine stimulates eryptosis. Methods: Cell volume has been estimated from forward scatter, phosphatidylserine-exposure from annexin V binding, [Ca2+]i from Fluo3-fluorescence, reactive oxygen species from 2',7'-dichlorodihydrofluorescein-diacetate fluorescence, content of reduced glutathione (GSH from mercury orange fluorescence, and ceramide abundance from binding of fluorescent antibodies in flow cytometry. Results: A 48 h exposure to lumefantrine (3 µg/mL was followed by a significant increase of annexin-V-binding without significantly altering forward scatter, [Ca2+]i, ROS formation, reduced GSH, or ceramide abundance. The annexin-V-binding following lumefantrine treatment was not significantly modified by p38 kinase inhibitors SB203580 (2 μM and p38 Inh III (1 μM, PKC inhibitor staurosporine (1 µM or pancaspase inhibitor zVAD (1 or 10 µM. Conclusions: Lumefantrine triggers cell membrane scrambling, an effect independent from entry of extracellular Ca2+, ceramide formation, ROS formation, glutathione content, p38 kinase, PKC or caspases.

  15. Optical properties of biomimetic probes engineered from erythrocytes

    Science.gov (United States)

    Burns, Joshua M.; Saager, Rolf; Majaron, Boris; Jia, Wangcun; Anvari, Bahman

    2017-01-01

    Light-activated theranostic materials offer a potential platform for optical imaging and phototherapeutic applications. We have engineered constructs derived from erythrocytes, which can be doped with the FDA-approved near infrared (NIR) chromophore, indocyanine green (ICG). We refer to these constructs as NIR erythrocyte-mimicking transducers (NETs). Herein, we investigated the effects of changing the NETs mean diameter from micron- (≈4 μm) to nano- (≈90 nm) scale, and the ICG concentration utilized in the fabrication of NETs from 5 to 20 μM on the resulting absorption and scattering characteristics of the NETs. Our approach consisted of integrating sphere-based measurements of light transmittance and reflectance, and subsequent utilization of these measurements in an inverse adding-doubling algorithm to estimate the absorption (μ a) and reduced scattering (μ s‧) coefficients of these NETs. For a given NETs diameter, values of μ a increased over the approximate spectral band of 630-860 nm with increasing ICG concentration. Micron-sized NETs produced the highest peak value of μ a when using ICG concentrations of 10 and 20 μM, and showed increased values of μ s‧ as compared to nano-sized NETs. Spectral profiles of μ s‧ for these NETs showed a trend consistent with Mie scattering behavior for spherical objects. For all NETs investigated, changing the ICG concentration minimally affected the scattering characteristics. A Monte Carlo-based model of light distribution showed that the presence of these NETs enhanced the fluence levels within simulated blood vessels. These results provide important data towards determining the appropriate light dosimetry parameters for an intended light-based biomedical application of NETs.

  16. Public perceptions of farm animal cloning in Europe

    DEFF Research Database (Denmark)

    Lassen, Jesper

    This report presents a picture of European opinion on farm animal cloning. In the report, both agricultural and biomedical applications of farm animal cloning are considered. With the arrival of Dolly, animal cloning became an integral part of the biotech debate, but this debate did not isolate...... animal cloning as a single issue....

  17. Cloning: Past, Present, and the Exciting Future. Breakthroughs in Bioscience.

    Science.gov (United States)

    Di Berardino, Marie A.

    This document explores the history of cloning by focusing on Dolly the Sheep, one of the first large animal clonings. The disadvantages and advantages of transgenic clones are discussed as well as the future implications of cloning from the perspective of human health. (Contains 10 resources.) (YDS)

  18. AN APPROACH FOR CLONE DETECTION IN DOCUMENTATION REUSE

    Directory of Open Access Journals (Sweden)

    D. V. Lutsiv

    2014-07-01

    Full Text Available The paper focuses on the searching method for repetitions in DocBook/DRL or plain text documents. An algorithm has been designed based on software clone detection. The algorithm supports filtering results: clones are rejected if clone length in the group is less than 5 symbols, intersection of clone groups is eliminated, meaningfulness clones are removed, the groups containing clones consisting only of XML are eliminated. Remaining search is supported: found clones are extracted from the documentation, and clone search is repeated. One step is proved to be enough. Adaptive reuse technique of Paul Bassett – Stan Jarzabek has been implemented. A software tool has been developed on the basis of the algorithm. The tool supports setting parameters for repetitions detection and visualization of the obtained results. The tool is integrated into DocLine document development environment, and provides refactoring of documents using found clones. The Clone Miner clone detection utility is used for clones search. The method has been evaluated for Linux Kernel Documentation (29 documents, 25000 lines. Five semantic kinds of clones have been selected: terms (abbreviations, one word and two word terms, hyperlinks, license agreements, functionality description, and code examples. 451 meaningful clone groups have been found, average clone length is 4.43 tokens, and average number of clones in a group is 3.56.

  19. New insights on the regulation of the adenine nucleotide pool of erythrocytes in mouse models

    Science.gov (United States)

    O’Brien, William G.; Ling, Han Shawn; Lee, Cheng Chi

    2017-01-01

    The observation that induced torpor in non-hibernating mammals could result from an increased AMP concentration in circulation led our investigation to reveal that the added AMP altered oxygen transport of erythrocytes. To further study the effect of AMP in regulation of erythrocyte function and systemic metabolism, we generated mouse models deficient in key erythrocyte enzymes in AMP metabolism. We have previously reported altered erythrocyte adenine nucleotide levels corresponding to altered oxygen saturation in mice deficient in both CD73 and AMPD3. Here we further investigate how these Ampd3-/-/Cd73-/- mice respond to the administered dose of AMP in comparison with the control models of single enzyme deficiency and wild type. We found that Ampd3-/-/Cd73-/- mice are more sensitive to AMP-induced hypometabolism than mice with a single enzyme deficiency, which are more sensitive than wild type. A dose-dependent rightward shift of erythrocyte p50 values in response to increasing amounts of extracellular AMP was observed. We provide further evidence for the direct uptake of AMP by erythrocytes that is insensitive to dipyridamole, a blocker for ENT1. The uptake of AMP by the erythrocytes remained linear at the highest concentration tested, 10mM. We also observed competitive inhibition of AMP uptake by ATP and ADP but not by the other nucleotides and metabolites tested. Importantly, our studies suggest that AMP uptake is associated with an erythrocyte ATP release that is partially sensitive to inhibition by TRO19622 and Ca++ ion. Taken together, our study suggests a novel mechanism by which erythrocytes recycle and maintain their adenine nucleotide pool through AMP uptake and ATP release. PMID:28746349

  20. Erythrocyte-derived microparticles supporting activated protein C-mediated regulation of blood coagulation.

    Science.gov (United States)

    Koshiar, Ruzica Livaja; Somajo, Sofia; Norström, Eva; Dahlbäck, Björn

    2014-01-01

    Elevated levels of erythrocyte-derived microparticles are present in the circulation in medical conditions affecting the red blood cells. Erythrocyte-derived microparticles expose phosphatidylserine thus providing a suitable surface for procoagulant reactions leading to thrombin formation via the tenase and prothrombinase complexes. Patients with elevated levels of circulating erythrocyte-derived microparticles have increased thrombin generation in vivo. The aim of the present study was to investigate whether erythrocyte-derived microparticles are able to support the anticoagulant reactions of the protein C system. Erythrocyte-derived microparticles were isolated using ultracentrifugation after incubation of freshly prepared erythrocytes with the ionophore A23187 or from outdated erythrocyte concentrates, the different microparticles preparations yielding similar results. According to flow cytometry analysis, the microparticles exposed phoshatidylserine and bound lactadherin, annexin V, and protein S, which is a cofactor to activated protein C. The microparticles were able to assemble the tenase and prothrombinase complexes and to stimulate the formation of thrombin in plasma-based thrombin generation assay both in presence and absence of added tissue factor. The addition of activated protein C in the thrombin generation assay inhibited thrombin generation in a dose-dependent fashion. The anticoagulant effect of activated protein C in the thrombin generation assay was inhibited by a monoclonal antibody that prevents binding of protein S to microparticles and also attenuated by anti-TFPI antibodies. In the presence of erythrocyte-derived microparticles, activated protein C inhibited tenase and prothrombinase by degrading the cofactors FVIIIa and FVa, respectively. Protein S stimulated the Arg306-cleavage in FVa, whereas efficient inhibition of FVIIIa depended on the synergistic cofactor activity of protein S and FV. In summary, the erythrocyte-derived microparticle

  1. Dapsone hydroxylamine induces premature removal of human erythrocytes by membrane reorganization and antibody binding

    Science.gov (United States)

    Bordin, Luciana; Fiore, Cristina; Zen, Francesco; Coleman, Michael D; Ragazzi, Eugenio; Clari, Giulio

    2010-01-01

    BACKGROUND AND PURPOSE N-hydroxylation of dapsone leads to the formation of the toxic hydroxylamines responsible for the clinical methaemoglobinaemia associated with dapsone therapy. Dapsone has been associated with decreased lifespan of erythrocytes, with consequences such as anaemia and morbidity in patients treated with dapsone for malaria. Here, we investigated how dapsone and/or its hydroxylamine derivative (DDS-NHOH) induced erythrocyte membrane alterations that could lead to premature cell removal. EXPERIMENTAL APPROACH Erythrocytes from healthy donors were subjected to incubation with dapsone and DDS-NHOH for varying times and the band 3 protein tyrosine-phosphorylation process, band 3 aggregation, membrane alteration and IgG binding were all examined and compared with erythrocytes from two patients receiving dapsone therapy. KEY RESULTS The hydroxylamine derivative, but not dapsone (the parent sulphone) altered membrane protein interactions, leading both to aggregation of band 3 protein and to circulating autologous antibody binding, shown in erythrocytes from patients receiving dapsone therapy. The band 3 tyrosine-phosphorylation process can be used as a diagnostic system to monitor membrane alterations both in vitro, assessing concentration and time-dependent effects of DDS-NHOH treatment, and in vivo, evaluating erythrocytes from dapsone-treated patients, in resting or oxidatively stimulated conditions. CONCLUSIONS AND IMPLICATIONS DDS-NHOH-induced alterations of human erythrocytes can be directly monitored in vitro by tyrosine-phosphorylation level and formation of band 3 protein aggregates. The latter, together with antibody-mediated labelling of erythrocytes, also observed after clinical use of dapsone, may lead to shortening of erythrocyte lifespan. PMID:20662842

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

    Science.gov (United States)

    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. The Trw type IV secretion system of Bartonella mediates host-specific adhesion to erythrocytes.

    Directory of Open Access Journals (Sweden)

    Muriel Vayssier-Taussat

    2010-06-01

    Full Text Available Bacterial pathogens typically infect only a limited range of hosts; however, the genetic mechanisms governing host-specificity are poorly understood. The alpha-proteobacterial genus Bartonella comprises 21 species that cause host-specific intraerythrocytic bacteremia as hallmark of infection in their respective mammalian reservoirs, including the human-specific pathogens Bartonella quintana and Bartonella bacilliformis that cause trench fever and Oroya fever, respectively. Here, we have identified bacterial factors that mediate host-specific erythrocyte colonization in the mammalian reservoirs. Using mouse-specific Bartonella birtlesii, human-specific Bartonella quintana, cat-specific Bartonella henselae and rat-specific Bartonella tribocorum, we established in vitro adhesion and invasion assays with isolated erythrocytes that fully reproduce the host-specificity of erythrocyte infection as observed in vivo. By signature-tagged mutagenesis of B. birtlesii and mutant selection in a mouse infection model we identified mutants impaired in establishing intraerythrocytic bacteremia. Among 45 abacteremic mutants, five failed to adhere to and invade mouse erythrocytes in vitro. The corresponding genes encode components of the type IV secretion system (T4SS Trw, demonstrating that this virulence factor laterally acquired by the Bartonella lineage is directly involved in adherence to erythrocytes. Strikingly, ectopic expression of Trw of rat-specific B. tribocorum in cat-specific B. henselae or human-specific B. quintana expanded their host range for erythrocyte infection to rat, demonstrating that Trw mediates host-specific erythrocyte infection. A molecular evolutionary analysis of the trw locus further indicated that the variable, surface-located TrwL and TrwJ might represent the T4SS components that determine host-specificity of erythrocyte parasitism. In conclusion, we show that the laterally acquired Trw T4SS diversified in the Bartonella lineage

  4. The Effects of Electromagnetic Fields Generated from 1800 MHz Cell Phones on Erythrocyte Rheological Parameters and Zinc Level in Rats

    Directory of Open Access Journals (Sweden)

    Ümit Divrikli

    2012-06-01

    Full Text Available Objective: The aim of this study was to investigate the effects of the electromagnetic field generated from the 1800 MHz radiofrequency radiation (EF on erythrocyte rheological parameters and erythrocyte zinc levels. Material and Methods: Twenty-four male Wistar Albino rats were randomly grouped as follows: 1 two control groups and 2 study groups: i Group A: EF exposed group (2.5 h/day for 30 days, the phone on stand-by, and ii Group B: EF exposed group (2.5 min/day for 30 days, the phone ringing in silent mode. At the end of the experimental period erythrocyte rheological parameters such as erythrocyte deformability and aggregation were determined by an ectacytometer. Erythrocyte zinc level, which affects hemorheological parameters, was also measured by atomic absorption spectrophotometer. Results: Erythrocyte deformability was decreased in both study groups but the decrease in group A was not statistically significant. Exposure to EF did not have any significant effect on erythrocyte aggregation. On the other hand, erythrocyte zinc level was significantly reduced in both study groups. Conclusion: Exposure to EF may have decreased tissue oxygenation due to reduced erythrocyte deformability. Decrease in erythrocyte zinc level may have caused the impairment in erythrocyte deformability.

  5. The Effects of Electromagnetic Fields Generated from 1800 MHz Cell Phones on Erythrocyte Rheological Parameters and Zinc Level in Rats.

    Science.gov (United States)

    Erken, Gülten; Küçükatay, Melek Bor; Turgut, Sebahat; Erken, Haydar Ali; Cömlekçi, Selçuk; Divrikli, Umit; Genç, Osman

    2012-06-01

    The aim of this study was to investigate the effects of the electromagnetic field generated from the 1800 MHz radiofrequency radiation (EF) on erythrocyte rheological parameters and erythrocyte zinc levels. Twenty-four male Wistar Albino rats were randomly grouped as follows: 1) two control groups and 2) study groups: i) Group A: EF exposed group (2.5 h/day for 30 days, the phone on stand-by), and ii) Group B: EF exposed group (2.5 min/day for 30 days, the phone ringing in silent mode). At the end of the experimental period erythrocyte rheological parameters such as erythrocyte deformability and aggregation were determined by an ectacytometer. Erythrocyte zinc level, which affects hemorheological parameters, was also measured by atomic absorption spectrophotometer. Erythrocyte deformability was decreased in both study groups but the decrease in group A was not statistically significant. Exposure to EF did not have any significant effect on erythrocyte aggregation. On the other hand, erythrocyte zinc level was significantly reduced in both study groups. Exposure to EF may have decreased tissue oxygenation due to reduced erythrocyte deformability. Decrease in erythrocyte zinc level may have caused the impairment in erythrocyte deformability.

  6. Impairment of Barrier Properties of Erythrocyte Membranes Caused by Low Temperatures is a Result of Disorganization of Hemoglobin Supramolecular Structure.

    Science.gov (United States)

    Gulevskvy, A K; Repin, N V; Schenvavsky, I I

    The antecedence of impairment of plasmatic membrane structure and functions forms the basis of the dominative concept about mechanisms of cell cryoinjuries. A role of alterations of hemoglobin supramolecular structure in erythrocytes remains unclear. Comparison of continuity of membranes of native erythrocytes and resealed ghosts after freeze-thawing with a cryoprotectant at a low concentration (4%). Cryoresistance of native erythrocytes and resealed ghosts with and without low concentrations of cryoprotectants (4% glycerol) was compared according to egress of the following markers: hemoglobin, 14С-sucrose and K+ as well as by scanning electron microscopy. It was found that resealed erythrocyte ghosts, where hemoglobin content was 4-5 times lower than in erythrocytes, were much more cryoresistant than native erythrocytes, which was especially noticeable when a low concentration of cryoprotectant (4% glycerol) was used. These data confirm an earlier proposed hypothesis on the role of supramolecular hemoglobin structure in cryoinjury mechanisms of erythrocytes.

  7. In vitro studies of graphene oxide reinforced hydroxyapatite nanobiocomposite on human erythrocytes

    Science.gov (United States)

    Radha, G.; Rohith Vinod, K.; Venkatesan, Balaji; Vellaichamy, Elangovan; Balakumar, S.

    2017-05-01

    We report the interaction of graphene oxide reinforced hydroxyapatite (GO-HAp) nanocomposites with human erythrocytes. The hemocompatibility of GO-HAp found to be superior as compared to the pristine graphene oxide. It is found that the HAp nanoparticles on GO decrease the disruption of erythrocytes by minimizing the exposure of oxygen groups to phosphatidylcholine surface of erythrocyte membrane and it enhances hemocompatibility. Further, it is also found that the graphene oxide reinforced HAp nanobiocomposite enhances the metabolic activity of osteoblasts-like cells by promoting cell proliferation.

  8. Encapsulation of interleukin-2 in murine erythrocytes and subsequent deposition in mice receiving a subcutaneous injection

    Energy Technology Data Exchange (ETDEWEB)

    DeLoach, J.R.; Andrews, K.; Sheffield, C.L.

    1988-04-01

    Radiolabeled recombinant human interleukin-2 (IL-2) was successfully encapsulated in both mouse and sheep erythrocytes. Of the added IL-2, 70% was recovered bound to or encapsulated within the carrier cells. Erythrocytes containing IL-2 were stable in vitro and most of the IL-2 remained associated with the cells following a 16-h incubation at 37 degrees C. When carrier erythrocytes containing IL-2 were injected subcutaneously into mice, intact (/sup 35/S)IL-2 was detectable in a number of tissues 3 days after injection.

  9. Association of aggressive periodontitis with reduced erythrocyte counts and reduced hemoglobin levels.

    Science.gov (United States)

    Anand, P S; Sagar, D K; Ashok, S; Kamath, K P

    2014-12-01

    Studies have shown that erythrocyte counts and hemoglobin levels are reduced in patients with chronic periodontitis, suggesting that this condition may be associated with anemia of chronic disease. Although increased leukocyte counts have been reported in aggressive periodontitis, very little is known about the effects of aggressive periodontitis on erythrocyte counts. The present study was undertaken to determine whether generalized aggressive periodontitis is associated with reduced erythrocyte counts and reduced hemoglobin levels. The present study was conducted as a case-control study in which 64 patients with generalized aggressive periodontitis were categorized as cases and 58 periodontally healthy individuals were categorized as controls. Erythrocyte parameters (such as erythrocyte count, hemoglobin concentration, and hematocrit and erythrocyte indices) and clinical parameters (such as gingival index, plaque index, probing depth, clinical attachment level and percentage of severe sites) were recorded. Significant differences were observed between cases and controls in mean erythrocyte count (4.45 ± 0.6 × 10(6) erythrocytes/μL and 4.78 ± 0.56 × 10(6) erythrocytes/μL respectively, p = 0.002) and hemoglobin level (12.43 ± 1.83 g/dL and 13.53 ± 1.64 g/dL, respectively, p = 0.001). Other erythrocyte parameters, such as hematocrit, mean corpuscular volume and mean corpuscular hemoglobin, were also significantly lower among cases compared with controls. Logistic regression analyses showed that generalized aggressive periodontitis was significantly associated with lower erythrocyte counts ( p = 0.032) and a lower hemoglobin concentration ( p = 0.017). The findings of the present study suggest that patients with generalized aggressive periodontitis tend to have lower erythrocyte counts and lower hemoglobin levels compared with periodontally healthy controls. This suggests that generalized aggressive periodontitis, like chronic

  10. Phase measurements of erythrocytes affected by metal ions with quantitative interferometric microscopy

    Science.gov (United States)

    Wang, Shouyu; Yan, Keding; Shan, Yanke; Xu, Mingfei; Liu, Fei; Xue, Liang

    2015-12-01

    Erythrocyte morphology is an important factor in disease diagnosis, however, traditional setups as microscopes and cytometers cannot provide enough quantitative information of cellular morphology for in-depth statistics and analysis. In order to capture variations of erythrocytes affected by metal ions, quantitative interferometric microscopy (QIM) is applied to monitor their morphology changes. Combined with phase retrieval and cell recognition, erythrocyte phase images, as well as phase area and volume, can be accurately and automatically obtained. The research proves that QIM is an effective tool in cellular observation and measurement.

  11. Identification of novel genetic determinants of erythrocyte membrane fatty acid composition among Greenlanders

    DEFF Research Database (Denmark)

    Andersen, Mette Korre; Jørsboe, Emil; Sandholt, Camilla Helene

    2016-01-01

    the understanding of the mechanisms and pathways involved in regulation of FA tissue levels, by identifying genetic loci associated with inter-individual differences in erythrocyte membrane FA levels. We assessed the levels of 22 FAs in the phospholipid fraction of erythrocyte membranes from 2,626 Greenlanders.......181), p = 2.8x10-4). In conclusion, we have identified novel genetic determinants of FA composition in phospholipids in erythrocyte membranes, and have shown examples of links between genetic variants associated with altered FA membrane levels and changes in metabolic traits....

  12. Method for Determining Erythrocyte Surface Area by Polarization and Nephelometric Measurements

    Science.gov (United States)

    Kugeiko, M. M.; Smunev, D. A.

    2016-01-01

    We propose a fast method for determining the surface area and volume of erythrocytes in the biconcave-discoid shape, based on establishing regression relations between the parameters to be determined and the angular polarization coefficients P(Θ) and scattering indicatrix σ(Θ). We have shown that using σ(Θ) for angles 6° and 17°, P(Θ) for angles 81° and 119° lets us determine the surface area of the erythrocytes within ≈1% and the volume of the erythrocytes within ≈2%.

  13. Occupational cadmium exposure-associated oxidative stress and erythrocyte fragility among jewelry workers in India.

    Science.gov (United States)

    Moitra, Subhabrata; Brashier, Bill B; Sahu, Subhashis

    2014-09-01

    Cadmium-induced pulmonary and renal target organ effects are well-established although its association with oxidative stress and associated hematological effects for human toxicity remain understudied. In a population of cadmium-exposed male jewelry manufacturing workers (n = 32) and referents without direct exposure (n = 21), all with urinary cadmium quantification, we measured plasma antioxidant enzymes (catalase, superoxide dismutase), lipid peroxidation (malondialdehyde), erythrocyte fragility, and surface irregularity of the erythrocyte membrane. Compared to referents, exposed workers manifested significantly lower plasma antioxidant enzymes, and increased malondialdehyde and erythrocyte fragility (for all, P toxicity. © 2014 Wiley Periodicals, Inc.

  14. Cytotoxic effect of poly-dispersed single walled carbon nanotubes on erythrocytes in vitro and in vivo.

    Science.gov (United States)

    Sachar, Sumedha; Saxena, Rajiv K

    2011-01-01

    Single wall Carbon Nanotubes (SWCNTs) are hydrophobic and do not disperse in aqueous solvents. Acid functionalization of SWCNTs results in attachment of carboxy and sulfonate groups to carbon atoms and the resulting acid functionalized product (AF-SWCNTs) is negatively charged and disperses easily in water and buffers. In the present study, effect of AF-SWCNTs on blood erythrocytes was examined. Incubation of mouse erythrocytes with AF-SWCNTs and not with control SWCNTs, resulted in a dose and time dependent lysis of erythrocyte. Using fluorescence tagged AF-SWCNTs, binding of AF-SWCNTs with erythrocytes could be demonstrated. Confocal microscopy results indicated that AF-SWCNTs could enter the erythrocytes. Treatment with AF-SWCNTs resulted in exposure of hydrophobic patches on erythrocyte membrane that is indicative of membrane damage. A time and dose dependent increase in externalization of phosphatidylserine on erythrocyte membrane bilayer was also found. Administration of AF-SWCNTs through intravenous route resulted in a transient anemia as seen by a sharp decline in blood erythrocyte count accompanied with a significant drop in blood haemoglobin level. Administration of AF-SWCNTs through intratracheal administration also showed significant decline in RBC count while administration through other routes (gavage and intra-peritoneal) was not effective. By using a recently developed technique of a two step in vivo biotinylation of erythrocytes that enables simultaneous enumeration of young (age 40 days) erythrocytes in mouse blood, it was found that the in vivo toxic effect of AF-SWCNTs was more pronounced on older subpopulation of erythrocytes. Subpopulation of old erythrocytes fell after treatment with AF-SWCNTs but recovered by third day after the intravenous administration of AF-SWCNTs. Taken together our results indicate that treatment with AF-SWCNTs results in acute membrane damage and eventual lysis of erythrocytes. Intravenous administration of AF

  15. Enhanced suicidal erythrocyte death in mice carrying a loss-of-function mutation of the adenomatous polyposis coli gene

    Science.gov (United States)

    Qadri, Syed M; Mahmud, Hasan; Lang, Elisabeth; Gu, Shuchen; Bobbala, Diwakar; Zelenak, Christine; Jilani, Kashif; Siegfried, Alexandra; Föller, Michael; Lang, Florian

    2012-01-01

    Abstract Loss-of-function mutations in human adenomatous polyposis coli (APC) lead to multiple colonic adenomatous polyps eventually resulting in colonic carcinoma. Similarly, heterozygous mice carrying defective APC (apcMin/+) suffer from intestinal tumours. The animals further suffer from anaemia, which in theory could result from accelerated eryptosis, a suicidal erythrocyte death triggered by enhanced cytosolic Ca2+ activity and characterized by cell membrane scrambling and cell shrinkage. To explore, whether APC-deficiency enhances eryptosis, we estimated cell membrane scrambling from annexin V binding, cell size from forward scatter and cytosolic ATP utilizing luciferin–luciferase in isolated erythrocytes from apcMin/+ mice and wild-type mice (apc+/+). Clearance of circulating erythrocytes was estimated by carboxyfluorescein-diacetate-succinimidyl-ester labelling. As a result, apcMin/+ mice were anaemic despite reticulocytosis. Cytosolic ATP was significantly lower and annexin V binding significantly higher in apcMin/+ erythrocytes than in apc+/+ erythrocytes. Glucose depletion enhanced annexin V binding, an effect significantly more pronounced in apcMin/+ erythrocytes than in apc+/+ erythrocytes. Extracellular Ca2+ removal or inhibition of Ca2+ entry with amiloride (1 mM) blunted the increase but did not abrogate the genotype differences of annexin V binding following glucose depletion. Stimulation of Ca2+-entry by treatment with Ca2+-ionophore ionomycin (10 μM) increased annexin V binding, an effect again significantly more pronounced in apcMin/+ erythrocytes than in apc+/+ erythrocytes. Following retrieval and injection into the circulation of the same mice, apcMin/+ erythrocytes were more rapidly cleared from circulating blood than apc+/+ erythrocytes. Most labelled erythrocytes were trapped in the spleen, which was significantly enlarged in apcMin/+ mice. The observations point to accelerated eryptosis and subsequent clearance of apcMin/+ erythrocytes

  16. Phenomenon of Cloning and specificity of its usage

    OpenAIRE

    Yusubova, Zyliya; Zeremskaya, Yuliya Aleksandrovna

    2017-01-01

    Cloning is studied by different branches of science. Medicine is interested in cloning because of its ability to transplant special tissues and organs, genetics - with the purpose of studying heredity and succession, sociology deals with moral and ethic aspects of the phenomenon. The paper is devoted to the study of cloning, its special features and usage in different spheres of social life. The article represents main types of cloning, specificity of vegetative and animal cloning and problem...

  17. Cloning mice and men: prohibiting the use of iPS cells for human reproductive cloning.

    Science.gov (United States)

    Lo, Bernard; Parham, Lindsay; Alvarez-Buylla, Arturo; Cedars, Marcelle; Conklin, Bruce; Fisher, Susan; Gates, Elena; Giudice, Linda; Halme, Dina Gould; Hershon, William; Kriegstein, Arnold; Kwok, Pui-Yan; Wagner, Richard

    2010-01-08

    The use of iPSCs and tetraploid complementation for human reproductive cloning would raise profound ethical objections. Professional standards and laws that ban human reproductive cloning by somatic cell nuclear transfer should be revised to also forbid it by other methods, such as iPSCs via tetraploid complementation. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Update on the First Cloned Dog and Outlook for Canine Cloning.

    Science.gov (United States)

    Jang, Goo; Lee, ByeongChun

    2015-10-01

    As man's best friend, dogs have an important position in human society. Ten years ago, we reported the first cloned dog, and his birth has raised various scientific issues, such as those related to health, reproduction, and life span. He has developed without any unique health issues. In this article, we summarize and present perspectives on canine cloning.

  19. Benefits and problems with cloning animals.

    Science.gov (United States)

    Smith, L C; Bordignon, V; Babkine, M; Fecteau, G; Keefer, C

    2000-01-01

    Animal cloning is becoming a useful technique for producing transgenic farm animals and is likely to be used to produce clones from valuable adults. Other applications will also undoubtedly be discovered in the near future, such as for preserving endangered breeds and species. Although cloning promises great advantages for commerce and research alike, its outcome is not always certain due to high pregnancy losses and high morbidity and mortality during the neonatal period. Research into the mechanisms involved in the reprogramming of the nucleus is being conducted throughout the world in an attempt to better understand the molecular and cellular mechanisms involved in correcting these problems. Although the cause of these anomalies remains mostly unknown, similar phenotypes have been observed in calves derived through in vitro fertilization, suggesting that culture conditions are involved in these phenomena. In the meantime, veterinarians and theriogenologists have an important role to play in improving the efficiency of cloning by finding treatments to assure normal gestation to term and to develop preventative and curative care for cloned neonates. Images Figure 1. PMID:11143925

  20. Elephant grass clones for silage production

    Directory of Open Access Journals (Sweden)

    Rerisson José Cipriano dos Santos

    2013-02-01

    Full Text Available Ensiling warm-season grasses often requires wilting due to their high moisture content, and the presence of low-soluble sugars in these grasses usually demands the use of additives during the ensiling process. This study evaluated the bromatological composition of the fodder and silage from five Pennisetum sp. clones (IPA HV 241, IPA/UFRPE Taiwan A-146 2.114, IPA/UFRPE Taiwan A-146 2.37, Elephant B, and Mott. The contents of 20 Polyvinyl chloride (PVC silos, which were opened after 90 days of storage, were used for the bromatological analysis and the evaluation of the pH, nitrogen, ammonia, buffer capacity, soluble carbohydrates, and fermentation coefficients. The effluent losses, gases and dry matter recovery were also calculated. Although differences were observed among the clones (p < 0.05 for the concentrations of dry matter, insoluble nitrogen in acid detergents, insoluble nitrogen in neutral detergents, soluble carbohydrates, fermentation coefficients, and in vitro digestibility in the forage before ensiling, no differences were observed for most of these variables after ensiling. All of the clones were efficient in the fermentation process. The IPA/UFRPE TAIWAN A-146 2.37 clone, however, presented a higher dry matter concentration and the best fermentation coefficient, resulting in a better silage quality, compared to the other clones.