Evaluation of the repeated-dose liver micronucleus assay using N-nitrosomorpholine in young adult rats: report on collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/Japanese Environmental Mutagen Society (JEMS)-Mammalian Mutagenicity Study (MMS) Group.

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Hayashi, Aya; Kosaka, Mizuki; Kimura, Aoi; Wako, Yumi; Kawasako, Kazufumi; Hamada, Shuichi

2015-03-01

The present study was conducted to evaluate the suitability of a repeated-dose liver micronucleus (LMN) assay in young adult rats as a collaborative study by the Mammalian mutagenicity study (MMS) group. All procedures were performed in accordance with the standard protocols of the MMS Group. Six-week-old male Crl:CD(SD) rats (5 animals/group) received oral doses of the hepatocarcinogen N-nitrosomorpholine (NMOR) at 0 (control), 5, 10, and 30mg/kg/day (10mL/kg) for 14 days. Control animals received vehicle (water). Hepatocytes were collected from the liver 24h after the last dose, and the number of micronucleated hepatocytes (MNHEPs) was determined by microscopy. The number of micronucleated immature erythrocytes (MNIMEs) in the femoral bone marrow was also determined. The liver was examined using histopathologic methods after formalin fixation. The results showed statistically significant and dose-dependent increases in the number of MNHEPs in the liver at doses of 10mg/kg and greater when compared with the vehicle control. However, no significant increase was noted in the number of MNIMEs in the bone marrow at doses of up to 30mg/kg. Histopathology of the liver revealed hypertrophy and single cell necrosis of hepatocytes at doses of 5mg/kg and above. These results showed that the induction of micronuclei by NMOR was detected by the repeated-dose LMN assay, but not by the repeated-dose bone marrow micronucleus assay. Copyright © 2014 Elsevier B.V. All rights reserved.

Micronucleus induction as a measure of I-131 exposure

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Kasuba, V; Horvat, D [Inst. for Medical Recearch and Occupational Health, Zagreb (Croatia). Laboratory for Mutagenesis; Kusic, Z [Clinical Hospital Sestre Milosrdnice, Zagreb (Croatia). Dept. of Oncology and Nuclear Medicine; Vlatkovic, M [Clinical Hospital Centre, Zagreb (Croatia). Dept. of Nuclear Medicine and Radiation Protection

1994-10-01

The change of cell numbers in the peripheral blood following irradiation has been studied for many years, particularly in patients undergoing radiotherapy. Recently, attention is directed towards the use of cytogenetic-mutagenetic methods to estimate the biological effects of received radiation dose. The aim of our study was to identify the difference in number and distribution of micronucleus, depending of applied therapeutic dose of iodine-131. According to their diagnosis, six patients have received iodine-131 in range from 80 to 140 mCi, while in the other group of patients the dose values varied from 7 to 32 mCi. On in vitro peripheral blood lymphocyte cultures micronucleus test was applied. Micronucleus analyses were carried out before the treatment, 24, 48 and 96 hours after the oral application of radiopharmaceutical. The number of micronucleus is showing increase, depending on applied radioactivity of iodine-131 and duration of exposition. The clear dose response relationship was never found. These results illustrate the problem associated with the inhomogeneous distribution of dose which results from the concentration of incorporated radionuclide into thyroid or other tissues. (author).

Assessment of the genotoxicity of 137Cs radiation using Vicia-micronucleus, Tradescantia-micronucleus and Tradescantia-stamen-hair mutation bioassays.

Science.gov (United States)

Minouflet, Marion; Ayrault, Sophie; Badot, Pierre-Marie; Cotelle, Sylvie; Ferard, Jean-François

2005-01-01

Since the middle of the 20th century, ionizing radiations from radioactive isotopes including 137Cs have been investigated to determine their genotoxic impact on living organisms. The present study was designed to compare the effectiveness of three plant bioassays to assess DNA damage induced by low doses of 137Cs: Vicia-micronucleus test (Vicia-MCN), Tradescantia-micronucleus test (Trad-MCN) and Tradescantia-stamen-hair mutation test (Trad-SH) were used. Vicia faba (broad bean) and Tradescantia clone 4430 (spiderwort) were exposed to 137Cs according to different scenarios: external and internal (contamination) irradiations. Experiments were conducted with various levels of radioactivity in solution or in soil, using solid or liquid 137Cs sources. The three bioassays showed different sensitivities to the treatments. Trad-MCN appeared to be the most sensitive test (significative response from 1.5 kBq/200 ml after 30 h of contamination). Moreover, at comparable doses, internal irradiations led to larger effects for the three bioassays. These bioassays are effective tests for assessing the genotoxic effects of radioactive 137Cs pollution.

Assessment of the genotoxicity of 137Cs radiation using Vicia-micronucleus, Tradescantia-micronucleus and Tradescantia-stamen-hair mutation bioassays

International Nuclear Information System (INIS)

Minouflet, Marion; Ayrault, Sophie; Badot, Pierre-Marie; Cotelle, Sylvie; Ferard, Jean-Francois

2005-01-01

Since the middle of the 20th century, ionizing radiations from radioactive isotopes including 137 Cs have been investigated to determine their genotoxic impact on living organisms. The present study was designed to compare the effectiveness of three plant bioassays to assess DNA damage induced by low doses of 137 Cs: Vicia-micronucleus test (Vicia-MCN), Tradescantia-micronucleus test (Trad-MCN) and Tradescantia-stamen-hair mutation test (Trad-SH) were used. Vicia faba (broad bean) and Tradescantia clone 4430 (spiderwort) were exposed to 137 Cs according to different scenarios: external and internal (contamination) irradiations. Experiments were conducted with various levels of radioactivity in solution or in soil, using solid or liquid 137 Cs sources. The three bioassays showed different sensitivities to the treatments. Trad-MCN appeared to be the most sensitive test (significative response from 1.5 kBq/200 ml after 30 h of contamination). Moreover, at comparable doses, internal irradiations led to larger effects for the three bioassays. These bioassays are effective tests for assessing the genotoxic effects of radioactive 137 Cs pollution

Erythrocyte Sedimentation Rate (ESR): MedlinePlus Lab Test Information

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... K. Brunner & Suddarth's Handbook of Laboratory and Diagnostic Tests. 2 nd Ed, Kindle. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. Erythrocyte Sedimentation Rate (ESR); p. 267– ...

Evaluation of the repeated-dose liver micronucleus assay using 2,4-dinitrotoluene: a report of a collaborative study by CSGMT/JEMS.MMS.

Science.gov (United States)

Maeda, Akihisa; Tsuchiyama, Hiromi; Asaoka, Yoshiji; Hirakata, Mikito; Miyoshi, Tomoya; Oshida, Keiyu; Miyamoto, Yohei

2015-03-01

The liver micronucleus assay using young adult rats has the potential to detect liver carcinogens by repeated dosing, and could be expected to be integrated into repeated-dose toxicity studies using a hepatocyte isolation method without the traditional in situ collagenase perfusion. In this study, to assess the performance of the repeated-dose liver micronucleus assay, 2,4-dinitrotoluene (DNT), which is a rodent liver carcinogen, was administered orally to male rats at doses of 50, 100 and 200 mg/kg/day once daily for 14 or 28 consecutive days, and the frequencies of micronucleated hepatocytes (MNHEPs) and micronucleated immature erythrocytes (MNIMEs) were examined. Significant increases in the MNHEPs were observed at 50 mg/kg/day or more in the 14-day treatment, and 50 and 100 mg/kg/day in the 28-day treatment. These increases were dependent on both the dose and the number of administrations, which indicates the possibility that the MNHEPs accumulate as a result of repeated dosing. In contrast, no increase in the MNIMEs was observed. In conclusion, the repeated-dose liver micronucleus assay using young adult rats is sufficiently sensitive to detect the genotoxicity of 2,4-DNT at a low dose.

THE IMPORTANCE OF THE ERYTHROCYTES OSMOTIC FRAGILITY TEST PERFORMED IN CHILDREN WITH INDIRECT HYPERBILIRUB1NEMIA

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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.

CYTOKINESIS-BLOCK MICRONUCLEUS ASSAY IN HUMAN GLIOMA CELLS EXPOSED TO RADIATION

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Jerzy Slowinski

2011-05-01

Full Text Available Biological tests are efficient in reflecting the biological influences of several types of generally harmful exposures. The micronucleus assay is widely used in genotoxicity studies or studies on genomic damage in general. We present methodological aspects of cytokinesis-block micronucleus assay performed in human gliomas irradiated in vitro. Eight human glioblastoma cell lines obtained from DSMZ (Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Germany were gamma-irradiated (60Co over a dose range of 0-10 Gy. Cytokinesis-block micronucleus assay was performed to quantitate cytogenetic damage. The cells were fixed directly on dishes, stained with fluorochrome DAPI and evaluated under fluorescent and phase contrast microscope. The micronucleus frequency was expressed as a micronuclei (MN per binucleated cell (BNC ratio, calculated after scoring at least 100 BNC per dish. The frequency of spontaneous MN ranged from 0.17 to 0.613 (mean: 0.29 ± 0.14. After irradiation increase of MN frequency in the range of 0.312 - 2.241 (mean: 0.98 ± 0.68 was found at 10 Gy. Gliomas are extremely heterogenous in regard to cytogenetic effects of irradiation, as shown in this study by cytokinesis-block micronucleus assay. This test is easily performed on irradiated glioma cell lines and can assist in determining their radiosensitivity. However, in order to obtain reliable and reproducible results, precise criteria for MN scoring must be strictly followed. Simultaneous use of fluorescent and phase contrast equipment improves imaging of morphological details and can further optimize MN scoring.

Etoposide; colchicine; mitomycin C and cyclophosphamide tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster lung (CHL) cells at Covance laboratories; Harrogate UK in support of OECD draft Test Guideline 487.

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Fowler, Paul; Whitwell, James; Jeffrey, Laura; Young, Jamie; Smith, Katie; Kirkland, David

2010-10-29

The following genotoxic chemicals were tested in the in vitro micronucleus assay, at Covance Laboratories, Harrogate, UK in the Chinese hamster lung cell line CHL. Etoposide (a topoisomerase inhibitor), colchicine (an aneugen), mitomycin C (a DNA cross linking agent) and cyclophosphamide (an alkylating agent requiring metabolic activation) were treated with and without cytokinesis block (by addition of cytochalasin B). This work formed part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 for the in vitro micronucleus test. The toxicity measures used, detecting both cytostasis and cell death, were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index or cytokinesis blocked proliferation index in the presence of cytokinesis block. All of the chemicals tested gave significant increases in the percentage of micronucleated cells with and without cytokinesis block at concentrations giving approximately 60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcomes from this series of tests support the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

Micronucleus frequency in exfoliated buccal cells from hairdresser who expose to hair products

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Koh Hui Yee

2015-06-01

Full Text Available Background: Hairdresser is one of the fastest growing occupations in today’s society. Hairdresser help styling, cutting, colouring, perming, curling, straightening hair and various treatment to customer. Somehow, hairdresser are constantly exposed to chemical substances such as aromatic amines, hydrogen peroxide, thioglycolic acid, formaldehyde in hair products which can cause damage to human’s genome. Micronucleus is one of the effective biomarker for processes associated with the induction of DNA damage. Purpose: The aim of this study was to determine the micronucleus frequencies in buccal mucosa epithelial cells of hairdresser who were exposed to chemical of hair products. Method: This study was conducted on twenty female subjects, who were divided into 2 groups: exposed and non-exposed (control group. All subjects recruited were working in the same beauty salon. Buccal cells were obtained from each individual by using cytobrush. The cells were stained with modified Feulgen-Ronssenback method and counting of micronucleus per 1000 cell was done under light microscope. The data were analyzed using independent t-test and one-way Anova (p<0.05. Result: The result showed a significant difference in micronucleus frequency between 2 groups. There were a significantly increase of micronucleus frequency in hairdressers and increase of  micronucleus frequency with the longer duration of exposure. Conclusion: It concluded that the chemical substances of hair products had affected the micronucleus frequency ofthe epithelial cells in buccal mucosa of hairdressers.

Micronucleus test in mice fed on irradiated whole diet

International Nuclear Information System (INIS)

Reddy, P.P.; Reddi, O.S.; Pentiah, P.R.; Rani, M.V.U.; Devi, K.R.; Goud, S.N.

1981-01-01

Eight week old Swiss albino male mice were fed on freshly irradiated or unirradiated whole diet for one week. (Exposure was to 75 or 200 kR γ rays from a 1000 Ci 60 Co γ source at a dose rate of 584 R/min.) On the seventh day, six hours after feeding, the mice were killed and bone marrow preparations were made by the Schmid technique. From each group three animals were taken and from each animal 2000 polychromatic and normochromatic erythrocytes were scored. It was evident from the data obtained that the irradiated whole diet failed to induce any significant increase in the incidence of micronuclei in polychromatic erythrocytes. Similarly, there was no significant increase in the frequency of micronuclei in normochromatic erythrocytes when compared with control data. The polychromatic to normochromatic ratio was also unaffected. The diet consisted of wheat flour (60%). groundnut cake (20%), fish meal (8%), Bengal gram flour (8%), dried yeast (3%), salt/mineral mixture (1%) and traces of vitamins. (U.K.)

Radiation dose-response relationship of micronucleus occurrence in pollen mother cells of tradescantia

International Nuclear Information System (INIS)

Kim, Jin Kyu; Kim, Yeon Ku; Song, Hi Sup

1999-01-01

This study was carried out to investigate the radiation dose-response of micronucleus frequencies in Tradescantia pollen mother cells. The number of micronuclei increased in the tetrads as a result of chromosome deletion after irradiation. The maximal frequency of micronucleus showed a good dose-response relationship in the range of dose 0∼50 cGy. On the basis of the relationship, a dose of 1 cGy resulted in two additional micronuclei in 100 tetrads. The radiation dose-response relationship of micronucleus occurrence is prerequisite to biological monitoring of radiation and can be modified for biological risk assessment of toxicants, and to safety test of water or soil integrity

Role of the micronucleus in stomatogenesis in sexual reproduction of Paramecium tetraurelia: laser microbeam irradiation of the micronucleus

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Tam Laiwa; Ng, S.F.

1986-12-01

Fifteen amicronucleate cell lines and 22 cell lines with defective micronuclei were obtained following selective laser microbeam irradiation of the micronucleus. The amicronucleate cell lines showed reduced growth rate and formed abnormal oral apparatuses in asexual reproduction, and failed to produce any oral apparatus in autogamy. The 22 cell lines with defective micronucleus exhibited various abnormalities of the oral apparatus newly formed during autogamy. These abnormalities included the arrest of membranelle assembly, reduction in the length of the buccal cavity and oral membranelles, disruption of the organization of the membranelles, quadrulation of the dorsal peniculus, and failure of addition of membranellar basal body rows. Hence the micronucleus plays multiple roles in sexual stomatogenesis. Our results agree with the notion that the micronucleus acts during a critical period between the second meiotic division and up to the formation of the zygotic nucleus to control the early stage of oral membranelle assembly. Laser microbeam irradiation might have created recessive mutations and/or chromosomal aberrations, which were expressed during this critical period with the formation of abnormal postmeiotic nuclei.

Structural and numerical chromosome aberration inducers in liver micronucleus test in rats with partial hepatectomy.

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Itoh, Satoru; Hattori, Chiharu; Nagata, Mayumi; Sanbuissho, Atsushi

2012-08-30

The liver micronucleus test is an important method to detect pro-mutagens such as active metabolites not reaching bone marrow due to their short lifespan. We have already reported that dosing of the test compound after partial hepatectomy (PH) is essential to detect genotoxicity of numerical chromosome aberration inducers in mice [Mutat. Res. 632 (2007) 89-98]. In naive animals, the proportion of binucleated cells in rats is less than half of that in mice, which suggests a species difference in the response to chromosome aberration inducers. In the present study, we investigated the responses to structural and numerical chromosome aberration inducers in the rat liver micronucleus test. Two structural chromosome aberretion inducers (diethylnitrosamine and 1,2-dimethylhydrazine) and two numerical chromosome aberration inducers (colchicine and carbendazim) were used in the present study. PH was performed a day before or after the dosing of the test compound in 8-week old male F344 rats and hepatocytes were isolated 4 days after the PH. As a result, diethylnitrosamine and 1,2-dimethylhydrazine, structural chromosome aberration inducers, exhibited significant increase in the incidence of micronucleated hepatocyte (MNH) when given either before and after PH. Colchicine and carbendazim, numerical chromosome aberration inducers, did not result in any toxicologically significant increase in MNH frequency when given before PH, while they exhibited MNH induction when given after PH. It is confirmed that dosing after PH is essential in order to detect genotoxicity of numerical chromosome aberration inducers in rats as well as in mice. Regarding the species difference, a different temporal response to colchicine was identified. Colchicine increased the incidence of MNH 4 days after PH in rats, although such induction in mice was observed 8-10 days after PH. Copyright © 2012 Elsevier B.V. All rights reserved.

Cadmium chloride, benzo[a]pyrene and cyclophosphamide tested in the in vitro mammalian cell micronucleus test (MNvit) in the human lymphoblastoid cell line TK6 at Covance laboratories, Harrogate UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Fowler, Paul; Whitwell, James; Jeffrey, Laura; Young, Jamie; Smith, Katie; Kirkland, David

2010-10-29

The following genotoxic chemicals were tested in the in vitro micronucleus assay, at Covance Laboratories, Harrogate, UK in the human lymphoblastoid cell line TK6. Cadmium chloride (an inorganic carcinogen), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation) and cyclophosphamide (an alkylating agent requiring metabolic activation) were treated with and without cytokinesis block (by addition of cytochalasin B). This work formed part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 for the in vitro micronucleus test. The toxicity measures used, capable of detecting both cytostasis and cell death, were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index or cytokinesis blocked proliferation index in the presence of cytokinesis block. All of the chemicals tested gave significant increases in the percentage of micronucleated cells with and without cytokinesis block at concentrations giving approximately 60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcomes from this series of tests support the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in the in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

Cytochalasin-b micronucleus test of peripheral blood lymphocytes of Kozloduy NPP workers

International Nuclear Information System (INIS)

Hadjidekova, V.; Hristova, R.; Atanassova, P.; Stainova, A.; Popova, L.

2006-01-01

Full text: The cytokinesis-block micronucleus assay in peripheral blood lymphocytes was applied to evaluate occupational radiation exposure of 65 nuclear power plant workers. Blood samples were collected from 43 workers aged between 32-54 years, mean age 41,7 years. The accumulated radiation doses for each subject varied between 7,9 - 766,4 mSv, mean level of the whole group is 237,78 mSv. Controls were 22 healthy individuals, (13 male and 9 female), aged between 27-52 years, mean age 38,8 years, selected from the administrative staff. All subjects participating in this study were interviewed concerning health status, professional history, smoking habit and other aspects relevant to the study. At least 1000 binucleated cells were analysed per person. The detected frequencies of micronuclei in the control group were ranged between 4.0 and 23.5 per 1000 binucleated cells, with the average incidence yield of 12.16 ±5.59 %. The mean group value of the frequency of micronuclei in peripheral lymphocytes of exposed workers was found to be 18.46±6.72 % in 1000 cells. The difference between the mean frequency of micronuclei in the group of exposed subjects and the control group was statistically significant (P<0,001). The correlation coefficient for duration of employment and accumulated doses is 0,30 (P<0,05). After 1,5 Gy in vitro irradiation of peripheral blood from investigated workers and controls a decreased radiosensitivity of NPP workers is detected using micronucleus assay. Decreased radiosensitivity of the professionally exposed workers could be due to the phenomenon of adaptive response. Micronucleus assay in peripheral blood lymphocytes is useful approach in cytogenetic monitoring of occupationally exposed nuclear industry workers

The role of the micronucleus in stomatogenesis in sexual reproduction of Paramecium tetraurelia: laser microbeam irradiation of the micronucleus

International Nuclear Information System (INIS)

Tam Laiwa; Ng, S.F.

1986-01-01

Fifteen amicronucleate cell lines and 22 cell lines with defective micronuclei were obtained following selective laser microbeam irradiation of the micronucleus. The amicronucleate cell lines showed reduced growth rate and formed abnormal oral apparatuses in asexual reproduction, and failed to produce any oral apparatus in autogamy. The 22 cell lines with defective micronucleus exhibited various abnormalities of the oral apparatus newly formed during autogamy. These abnormalities included the arrest of membranelle assembly, reduction in the length of the buccal cavity and oral membranelles, disruption of the organization of the membranelles, quadrulation of the dorsal peniculus, and failure of addition of membranellar basal body rows. Hence the micronucleus plays multiple roles in sexual stomatogenesis. Our results agree with the notion that the micronucleus acts during a critical period between the second meiotic division and up to the formation of the zygotic nucleus to control the early stage of oral membranelle assembly. Laser microbeam irradiation might have created recessive mutations and/or chromosomal aberrations, which were expressed during this critical period with the formation of abnormal postmeiotic nuclei. (author)

Genotoxic, Cytotoxic, Antigenotoxic, and Anticytotoxic Effects of Sulfonamide Chalcone Using the Ames Test and the Mouse Bone Marrow Micronucleus Test.

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Carolina Ribeiro E Silva

Full Text Available Chalcones present several biological activities and sulfonamide chalcone derivatives have shown important biological applications, including antitumor activity. In this study, genotoxic, cytotoxic, antigenotoxic, and anticytotoxic activities of the sulfonamide chalcone N-{4-[3-(4-nitrophenylprop-2-enoyl]phenyl} benzenesulfonamide (CPN were assessed using the Salmonella typhimurium reverse mutation test (Ames test and the mouse bone marrow micronucleus test. The results showed that CPN caused a small increase in the number of histidine revertant colonies in S. typhimurium strains TA98 and TA100, but not statistically significant (p > 0.05. The antimutagenicity test showed that CPN significantly decreased the number of His+ revertants in strain TA98 at all doses tested (p 0.05. Additionally, CPN co-administered with MMC significantly increased PCE/NCE ratio at all doses tested, demonstrating its anticytotoxic effect. In summary, CPN presented genotoxic, cytotoxic, antigenotoxic, and anticytotoxic properties.

Micronucleus frequency and content in healthy relatives of cancer patients

Czech Academy of Sciences Publication Activity Database

Zölzer, F.; Křížová, M.; Skalická, Z.F.; Rössnerová, Andrea; Šrám, Radim

2017-01-01

Roč. 22, č. 7 (2017), s. 667-673 ISSN 1354-750X Institutional support: RVO:68378041 Keywords : micronucleus centromere test * chromosomal damage * inheritable trait Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Human genetics Impact factor: 2.006, year: 2016

Fish eco-genotoxicology: Comet and micronucleus assay in fish erythrocytes as in situ biomarker of freshwater pollution

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Bilal Hussain

2018-02-01

Full Text Available Owing to white meat production Labeo rohita have vast economic importance, but its population has been reduced drastically in River Chenab due to pollution. Atomic absorption spectrophotometry showed a merciless toxicity level of Cd, Cu, Mn, Zn, Pb, Cr, Sn and Hg. Comet assay results indicated significant (p < .05 DNA fragmentation in Labeo rohita as 42.21 ± 2.06%, 31.26 ± 2.41% and 21.84 ± 2.21% DNA in comet tail, tail moment as 17.71 ± 1.79, 10.30 ± 1.78 and 7.81 ± 1.56, olive moment as 13.58 ± 1.306, 8.10 ± 1.04 and 5.88 ± 0.06, respectively, from three different polluted sites on the river. Micronucleus assay showed similar findings of single micronucleus induction (MN as 50.00 ± 6.30‰, double MN 14.40 ± 2.56‰, while nuclear abnormalities (NA were found as 150.00 ± 2.92‰. These higher frequencies of MN induction and NA were found to be the cause of reduction of 96% of the population of this fish species in an experimental area of the River Chenab. This fish species has been found near extinction through the length of the river Chenab and few specimens in rainy seasons if restored by flood, may die in sugarcane mill season. Due to sweeping extinction Labeo rohita showed the highest sensitivity for pollution and could be used as bioindicator and DNA fragmentation in this column feeder fish species as a biomarker of the pollution load in freshwater bodies.

What Can a Micronucleus Teach? Learning about Environmental Mutagenesis

Science.gov (United States)

Linde, Ana R.; Garcia-Vazquez, Eva

2009-01-01

The micronucleus test is widely employed in environmental health research. It can also be an excellent tool for learning important concepts in environmental health. In this article we present an inquiry-based laboratory exercise where students explore several theoretical and practical aspects of environmental mutagenesis employing the micronucleus…

5-Fluorouracil, colchicine, benzo[a]pyrene and cytosine arabinoside tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster V79 cells at Covance Laboratories, Harrogate, UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Whitwell, James; Fowler, Paul; Allars, Sarah; Jenner, Karen; Lloyd, Melvyn; Wood, Debbie; Smith, Katie; Young, Jamie; Jeffrey, Laura; Kirkland, David

2010-10-29

The reference genotoxic agents 5-fluorouracil (a nucleoside analogue, characterised by a steep dose response profile), colchicine (an aneugen that inhibits tubulin polymerisation), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation) and cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair) were tested in the in vitro micronucleus assay using the Chinese hamster V79 cell line at Covance Laboratories, Harrogate, UK. All chemicals were treated in the absence and presence of cytokinesis block (via addition of cytochalasin B) with this work forming part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 on the In Vitro Mammalian Cell Micronucleus Test (MNvit). The toxicity measures used, detecting a possible combination of both cytostasis and cell death (though not cell death directly), were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index in the presence of cytokinesis block. All of the chemicals tested either gave marked increases in the percentage of micronucleated cells with and without cytokinesis block, or did not induce micronuclei at concentrations giving approximately 50-60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcome from this series of tests supports the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

Effect of Green Tea Extract in Reducing Genotoxic Injuries of Cell Phone Microwaves on Bone Marrow

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Zahra Zahedifar

2013-11-01

Full Text Available Background: Green tea (Camellia sinensis extract is rich source of natural antioxidants specially catechin that is quickly absorbed into the body and it has cancer protective, anti microbial and anti inflammation effects. In this study has been studied role of green tea extract against genotoxic damage induced by cell phone microwaves on bone marrow polychromatic erythrocytes of adult male Balb/C mouse.Materials and Methods: In this experimental study 40 mouse were divided into five groups, control animals were located under natural condition, sham -exposed animals were prepared by experimental condition without cell phone waves radiation. Experimental 1 group that irradiated at cell phones for 4 days (3 hours/day and experimental 2 groups were injected intraperitoneal 100 mg/kg green tea extract for 5 days and experimental 3 group that irradiated at active mobile phones for 4 days (3 hours/day and were injected intraperitoneal 100 mg/kg green tea extract for 5 days. After treatment period micronucleus test was evaluated in polychromatic erythrocytes on bone marrow. The quantitative data was analyzed by ANOVA and Tukey test with using of SPSS-13 software at the level of p<0.05.Results: Based on this study, treatment with extracts of green tea decreased micronucleus frequency in bone marrow polychromatic erythrocytes of Balb/C mouse that irradiated at cell phone microwave (0.92±0.129, (p<0.001.Conclusion: Cell phone microwaves (940 MHz increased micronucleus on bone marrow polychromatic erythrocytes of male Balb/C mouse, but green tea had inhibitory effect and it decreased the average number of micronucleus.

Biomonitoring of agricultural workers exposed to pesticide mixtures in Guerrero state, Mexico, with comet assay and micronucleus test.

Science.gov (United States)

Carbajal-López, Yolanda; Gómez-Arroyo, Sandra; Villalobos-Pietrini, Rafael; Calderón-Segura, María Elena; Martínez-Arroyo, Amparo

2016-02-01

The aim of this study was to evaluate the genotoxic effect of pesticides in exfoliated buccal cells of workers occupationally exposed in Guerrero, Mexico, using the comet assay and the micronucleus test. The study compared 111 agricultural workers in three rural communities (Arcelia 62, Ajuchitlan 13, and Tlapehuala 36), with 60 non-exposed individuals. All the participants were males. The presence of DNA damage was investigated in the exfoliated buccal cells of study participants with the comet assay and the micronucleus (MN) test; comet tail length was evaluated in 100 nuclei and 3000 epithelial cells of each individual, respectively; other nuclear anomalies such as nuclear buds, karyolysis, karyorrhexis, and binucleate cells were also evaluated. Study results revealed that the tail migration of DNA and the frequency of MN increased significantly in the exposed group, which also showed nuclear anomalies associated with cytotoxic or genotoxic effect. No positive correlation was noted between exposure time and tail length and micronuclei frequencies. No significant effect on genetic damage was observed as a result of age, smoking, and alcohol consumption. The MN and comet assay in exfoliated buccal cells are useful and minimally invasive methods for monitoring genetic damage in individuals exposed to pesticides. This study provided valuable data for establishing the possible risk to human health associated with pesticide exposure.

40 CFR 799.9539 - TSCA mammalian erythrocyte micronucleus test.

Science.gov (United States)

2010-07-01

... sampling time, unless acceptable inter-animal variability and frequencies of cells with micronuclei are...., Wehr, C.M., and Langlois, R.G. A Simple Fluorescent Staining Procedure for Micronuclei and RNA in...

Evaluation of a liver micronucleus assay in young rats (IV): a study using a double-dosing/single-sampling method by the Collaborative Study Group for the Micronucleus Test (CSGMT)/Japanese Environmental Mutagen Society (JEMS)-Mammalian Mutagenicity Study Group (MMS).

Science.gov (United States)

Takasawa, Hironao; Suzuki, Hiroshi; Ogawa, Izumi; Shimada, Yasushi; Kobayashi, Kazuo; Terashima, Yukari; Matsumoto, Hirotaka; Oshida, Keiyu; Ohta, Ryo; Imamura, Tadashi; Miyazaki, Atsushi; Kawabata, Masayoshi; Minowa, Shigenori; Maeda, Akihisa; Hayashi, Makoto

2010-04-30

A collaborative study was conducted to evaluate whether a liver micronucleus assay using four-week-old male F344 rats can be used to detect genotoxic rat hepatocarcinogens using double-dosing with a single-sampling 4 days after the second dose. The assay methods were thoroughly validated by the seven laboratories involved in the study. Seven chemicals, 2,4-diaminotoluene, diethyl nitrosamine, p-dimethylaminoazobenzene, 1,2-dimethylhydrazine dihydrochloride, 2,4-dinitrotolunene, 2,6-dinitrotoluene and mitomycin C, known to produce positive responses in the single-dosing/triple-sampling method were selected for use in the present study, and each chemical was examined in two laboratories with the exception of 2,4-dinitrotolunene. Although several of the compounds were examined at lower doses for reasons of toxicity than in the single-dosing/triple-sampling method, all chemicals tested in the present study induced micronuclei in liver cells indicating a positive result. These findings suggest that the liver micronucleus assay can be used in young rats to detect genotoxic rat hepatocarcinogens using a double-dosing/single-sampling procedure. Further, the number of animals used in the liver micronucleus assay can be reduced by one-third to a half by using the double-dosing/single-sampling method. This reduction in animal numbers also has significant savings in time and resource for liver perfusion and hepatocyte isolation. Copyright 2010 Elsevier B.V. All rights reserved.

Micronuclei and erythrocytic abnormalities frequencies of freshwater fishes: Establishing a baseline for health status

Science.gov (United States)

Sousa, Debora Batista Pinheiro; Torres, Audalio Rebelo; Oliveira, Suelen Rosana Sampaio; Castro, Jonatas da Silva; Neta, Raimunda Nonata Fortes Carvalho

2017-11-01

Majority papers shows that micronucleus test and erythrocyte abnormalities are excellent tools such as tools for monitor fish health and the level of impact in aquatic ecosystems. Nevertheless, still do not know the baseline for those changes in freshwater fishes communities in the Brazilian Northeastern river. In this study, we show the level of basis of two species of freshwater fishes (Colossoma macropomum -tambaqui and Oreochromis niloticus - tilápia) with the aim of establish levels of background these species. The animals were collected from Ambude river in the protected area and blood collected from all fish for analysis. Erythrocyte indices—mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC)—were calculated. Blood samples from all fish were examined for micronuclear changes after Giemsa staining. Micronuclei were found in fish from from Ambude River. The baseline values determined for tambaqui was (micronuclei= 0.0071±0.0026; MCV=0.0073±0.0037; MCHV=0.0071±0.0024) and tilapia (micronuclei= 0.0061±0.0026; MCV=0.0037±0.0017; MCHV=0.056±0.0036). We belive that, we propose using the genotoxic approach for estimating fish health status as the technique allows examination in locus of live fish without the need for animal euthanasia. Besides, baseline level can be to establish levels of background and patterns to pathological and physiological research of these species in future biomonitoring programs.

Fluorescence in situ hybridization in combination with the comet assay and micronucleus test in genetic toxicology

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Hovhannisyan Galina G

2010-09-01

Full Text Available Abstract Comet assay and micronucleus (MN test are widely applied in genotoxicity testing and biomonitoring. While comet assay permits to measure direct DNA-strand breaking capacity of a tested agent MN test allows estimating the induced amount of chromosome and/or genome mutations. The potential of these two methods can be enhanced by the combination with fluorescence in situ hybridization (FISH techniques. FISH plus comet assay allows the recognition of targets of DNA damage and repairing directly. FISH combined with MN test is able to characterize the occurrence of different chromosomes in MN and to identify potential chromosomal targets of mutagenic substances. Thus, combination of FISH with the comet assay or MN test proved to be promising techniques for evaluation of the distribution of DNA and chromosome damage in the entire genome of individual cells. FISH technique also permits to study comet and MN formation, necessary for correct application of these methods. This paper reviews the relevant literature on advantages and limitations of Comet-FISH and MN-FISH assays application in genetic toxicology.

75 FR 5546 - Proposed Significant New Use Rule for Multi-walled Carbon Nanotubes

Science.gov (United States)

2010-02-03

... effects of the PMN substance: A bacterial reverse mutation test (OPPTS Harmonized Test Guideline 870.5100) in vitro; a mammalian erythrocyte micronucleus test (OPPTS Harmonized Test Guideline 870.5395 or Organisation for Economic Co-operation and Development (OECD) 474 test guideline) in vivo, in bone marrow, by...

Cytokinesis-block micronucleus method in micro-blood cultures

International Nuclear Information System (INIS)

Liu Jinwen; Wang Lianzhi; Yang Cangzhen; Yao Yanyu

1991-01-01

This paper reports the cytokinesis-block micronucleus method in micro-blood cultures. The observations on detection induced micronuclei of different doses of 60 Co γ-rays irradiation and spontaneous micronucleus of different ages were performed with CB method in comporison with conventional micronucleus (CM) method. The results showed that with direct peripheral micro-blood cultures the cytoknesis-block micronuclei is also obtained. Using CB method, the micronuclei fequency of different ages was linear relationship, Y = 1.62 + 0.74 D, the spontaneous micronuclei frequency of different ages was 4.14%, the induced micronuclei also was a linear relationship, Y = 6.01 + 0.692 D. Using CM method, it showed that the induced micronuclei was a linear relationship, Y = 0.486 D - 1.968, but there is no significant difference between the micronuclei frequency of different ages. Comparison with CM and direct blood smear methods confirmed that the cytokinesis-block method of micro-blood cultures is more sensitive and precise

Assessment of the genotoxicity of Cu and Zn in raw and anaerobically digested slurry with the Vicia faba micronucleus test

OpenAIRE

Marcato, Claire-Emmanuelle; Pinelli, Eric; Pourrut, Bertrand; Silvestre, Jérôme; Guiresse, Agnès Maritchù

2009-01-01

Genotoxicity of Cu and Zn was assessed by use of the micronucleus (MN) test on Vicia faba roots. Plants were exposed to various leachates of rawand anaerobically digested pig slurry, with maximum total concentrations of 200MCu and 600MZn. The results indicated stabilisation of the organic matter during anaerobic digestion of the slurry and bioconversion of some phytotoxic organic compounds (e.g. phenols or p-cresol), but did not showa relationship between Cu and Zn concentrations and MN fr...

[Influence of Four Kinds of PPCPs on Micronucleus Rate of the Root-Tip Cells of Vicia-faba and Garlic].

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Wang, Lan-jun; Wang, Jin-hua; Zhu, Lu-sheng; Wang, Jun; Zhao, Xiang

2016-04-15

In order to determine the degree of biological genetic injury induced by PPCPs, the genotoxic effects of the doxycycline (DOX), ciprofloxacin (CIP), triclocarban (TCC) and carbamazepine (CBZ) in the concentration range of 12.5-100 mg · L⁻¹ were studied using micronucleus rate and micronucleus index of Vicia-fabe and garlic. The results showed that: (1) When the Vicia-faba root- tip cells were exposed to DOX, CIP, TCC and CBZ, micronucleus rates were higher than 1.67 ‰ (CK₁), it was significantly different from that of the control group (P garlic root tip cells were exposed to DOX, CIP, TCC and CBZ respectively, the micronucleus rates were less than those of the Vicia-faba, while in most treatments significantly higher than that of the control group (0.67‰). The micronucleus index was higher than 3.5 in the groups exposed to CIP with concentrations of 25, 50, 100 mg · L⁻¹ and TCC and CBZ with concentrations of 25 mg · L⁻¹; With the increase of exposure concentrations, the micronucleus rate showed a trend of first increasing and then decreasing as well. (3) Under the same experimental conditions, the cells micronucleus rates of the garlic cells caused by the four tested compounds were significantly lower than those of Vicia-faba. (4) The micronucleus index of the root tip cells of Vicia-faba and garlic treated with the four kinds of compounds followed the order of CIP > CBZ > TCC > DOX. These results demonstrated that the four compounds caused biological genetic injury to root-tip cells of Vicia-faba and garlic, and the genetic damage caused to garlic was significantly lower than that to Vicia-faba. The damages caused by the four kinds of different compounds were also different.

2-Aminoanthracene, 5-fluorouracil, colchicine, benzo[a]pyrene, cadmium chloride and cytosine arabinoside tested in the in vitro mammalian cell micronucleus test (MNvit) in Chinese hamster ovary (CHO) cells at Covance Laboratories, Harrogate UK in support of OECD draft Test Guideline 487.

Science.gov (United States)

Whitwell, James; Fowler, Paul; Allars, Sarah; Jenner, Karen; Lloyd, Melvyn; Wood, Debbie; Smith, Katie; Young, Jamie; Jeffrey, Laura; Kirkland, David

2010-10-29

The reference genotoxic agents 2-aminoanthracene (a metabolism dependent weak clastogen), 5-fluorouracil (a nucleoside analogue, characterised by a steep dose response profile), colchicine (an aneugen that inhibits tubulin polymerisation), benzo[a]pyrene (a polycyclic aromatic hydrocarbon requiring metabolic activation), cadmium chloride (an inorganic carcinogen), and cytosine arabinoside (a nucleoside analogue that inhibits the gap-filling step of excision repair) were tested in the in vitro micronucleus assay using the Chinese hamster ovary (CHO) cell line at Covance Laboratories, Harrogate, UK. All chemicals were treated in the absence and presence of cytokinesis block (via addition of cytochalasin B) with this work forming part of a collaborative evaluation of the toxicity measures recommended in the draft OECD Test Guideline 487 on the In vitro Mammalian Cell Micronucleus Test (MNvit). The toxicity measures used, detecting a possible combination of both cytostasis and cell death (though not cell death directly), were relative population doubling, relative increase in cell counts and relative cell counts for treatments in the absence of cytokinesis block, and replication index in the presence of cytokinesis block. All of the chemicals tested either gave marked positive increases in the percentage of micronucleated cells with and without cytokinesis block, or did not induce micronuclei at concentrations giving approximately 50-60% toxicity (cytostasis and cell death) or less by all of the toxicity measures used. The outcome from this series of tests supports the use of relative increase in cell counts and relative population doubling, as well as relative cell counts, as appropriate measures of cytotoxicity for the non-cytokinesis blocked in vitro micronucleus assay. Copyright © 2010 Elsevier B.V. All rights reserved.

Effects of zerumbone on cisplatin-induced clastogenesis in Sprague ...

African Journals Online (AJOL)

Administrator

2011-06-20

Jun 20, 2011 ... bol ester-induced papilloma formation in mouse skin which is another indication of its ... zerumbet plant. The rhizomes were obtained from the wet market in ... erythrocyte micronucleus test), guideline No. 474 (OECD 1997).

Dependence of the bystander effect for micronucleus formation on dose of heavy-ion radiation in normal human fibroblasts

International Nuclear Information System (INIS)

Matsumoto, Yoshitaka; Hamada, Nobuyuki; Aoki-Nakano, Mizuho; Furusawa, Yoshiya; Funayama, Tomoo; Sakashita, Tetsuya; Kobayashi, Yasuhiko; Wada, Seiichi; Kakizaki, Takehiko

2015-01-01

Ionising radiation-induced bystander effects are well recognised, but its dependence on dose or linear energy transfer (LET) is still a matter of debate. To test this, 49 sites in confluent cultures of AG01522D normal human fibroblasts were targeted with microbeams of carbon (103 keV μm -1 ), neon (375 keV μm -1 ) and argon ions (1260 keV μm -1 ) and evaluated for the bystander-induced formation of micronucleus that is a kind of a chromosome aberration. Targeted exposure to neon and argon ions significantly increased the micronucleus frequency in bystander cells to the similar extent irrespective of the particle numbers per site of 1- 6. In contrast, the bystander micronucleus frequency increased with increasing the number of carbon-ion particles in a range between 1 and 3 particles per site and was similar in a range between 3 and 8 particles per site. These results suggest that the bystander effect of heavy ions for micronucleus formation depends on dose. (authors)

Radiosensitiviness of blood lymphocytes from skin cancer patients and healthy volunteers as determined by micronucleus assay

International Nuclear Information System (INIS)

Lohmann, Tania Helena Ochi.

1995-01-01

Cancer, a major death cause in developed countries, has been related to somatic mutations that could be detected by cytogenetic analysis. Among the tools used in these tests, the micronucleus assay has been largely applied at population surveillance, biological dosimetry and early detection of groups with higher risks to developing cancers. In this study, we analysed the chromosome susceptibility of blood lymphocytes from basocellular skin cancer patients and healthy volunteers. The cytogenetic analysis was performed by a micronucleus assay, using progressive doses of ionizing radiation from a 60 Co source as mutagen. Briefly, the blood lymphocytes were irradiated in vitro, as processed by the cytokinesis-blocked method. The micronucleus frequency and distribution, cell cycle kinetics, nucleation index and dose-response relationship were determined in each patient. The results showed that the basocellular skin cancer patients lymphocytes presented higher spontaneous micronucleus frequency as compared with those from healthy young volunteers but lower than healthy now young volunteers . The radiation-induced micronucleus analysis showed that the basocellular skin cancer patients' lymphocytes presented similar proportion of damage lymphocytes as compared with those from healthy volunteers. Nevertheless, the magnitude of this damage was higher in this group with doses. Higher than 400 c Gy, which was not occurred in healthy volunteers. Cell cycle kinetics, as determined by the nucleation index, was lower in basocellular skin cancer patients as compared with healthy volunteers, indicating a more slow cell cycle. Our data showed that the lymphocytes from carcinoma basocellular patients were more radiosensitive as compared with those form healthy volunteers. (author). 159 refs., 21 figs., 16 tabs

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.

A simple slide test to assess erythrocyte aggregation in acute ST-elevated myocardial infarction and acute ischemic stroke: Its prognostic significance

Directory of Open Access Journals (Sweden)

Atla Bhagya Lakshmi

2011-01-01

Full Text Available A simple slide test and image analysis were used to reveal the presence of an acute-phase response and to determine its intensity in subjects of acute myocardial infarction and acute ischemic stroke. Erythrocytes tend to aggregate during an inflammatory process. Evaluation of erythrocyte adhesiveness/aggregation is currently available to the clinicians indirectly by erythrocyte sedimentation rate (ESR, but ESR correlates poorly with erythrocyte aggregation, hence a simple slide technique using citrated blood was used to evaluate erythrocyte aggregation microscopically and also by using image analysis. Aims: (1 To study erythrocyte aggregation/adhesiveness by a simple slide test in subjects with acute ST-elevated myocardial infarction (STEMI, acute ischemic stroke and healthy controls. (2 To study the prognostic significance of ESR and erythrocyte aggregation/adhesiveness test (EAAT in predicting the outcome after 1 week in subjects of acute myocardial infarction and acute ischemic stroke. Patients and Methods: Three groups of subjects were included in the study; 30 patients of acute STEMI, 30 patients of acute ischemic stroke, and 30 subjects with age- and gender-matched healthy controls. Citrated blood was subjected to simple slide test and ESR estimation by Westergren′s method. Stained smears were examined under 400Χ and graded into four grades. Images were taken from nine fields; three each from head, body, and tail of the smear. The degree of erythrocyte aggregation was quantified using a variable called erythrocyte percentage (EP, by using the software MATLAB Version 7.5. A simple program was used to count the number of black and white pixels in the image by selecting a threshold level. Results: The mean ESR of the subjects with acute myocardial infarction (29 + 17.34 was significantly higher (P = 0.001 than the mean ESR of the control group (15.5 + 12.37. The mean EP of the subjects with acute myocardial infarction (69.91 + 13.25 was

Mutagenic effects of tributyltin and inorganic lead (Pb II on the fish H. malabaricus as evaluated using the comet assay and the piscine micronucleus and chromosome aberration tests

Directory of Open Access Journals (Sweden)

Ferraro Marcos Vinícius M.

2004-01-01

Full Text Available Genotoxicity studies on toxic metals and their organic compounds are very important, especially so in the investigation of the effects of these compounds on the aquatic environments where they tend to accumulate. The use of endemic aquatic organisms as biological sentinels has proved useful to environmental monitoring. We assessed the mutagenic potential of tributyltin (TBT and inorganic lead (PbII using samples of the fish Hoplias malabaricus (commonly called traíra using the comet assay and the piscine micronucleus and chromosome aberration tests. Eighteen H. malabaricus were acclimatized in three individual aquariums, each containing six fish, six fish being exposed to 0.3 mg/g of body weight (bw of TBT, six to 21 mg/g bw of PbII and six being used as controls. Exposure to TBT and PbII was achieved by feeding the fish every five days with Astyanax (a small fish that is part of the normal diet of H. malabaricus which had been injected with solutions of TBT, PbII or with water (the control group. After two months the H. malabaricus were sacrificed and their peripheral blood collected and subjected to the comet and micronucleus assays, the chromosome aberration assay being conducted using kidney-tissue. Although the comet assay showed now mutagenic effects at the lead concentrations used but encountered results with TBT, the micronucleus and chromosome aberrations assays both indicated that TBT and PbII are potentially mutagenic (p < 0.01, the micronucleus assay showing morphological alterations of the nucleus.

Evaluation of the repeated dose liver micronucleus assay using young adult rats with cyclophosphamide monohydrate: a report of a collaborative study by CSGMT/JEMS.MMS.

Science.gov (United States)

Matsumoto, Kazumi; Zaizen, Kazuyo; Miyamoto, Atsushi; Wako, Yumi; Kawasako, Kazufumi; Ishida, Hisao

2015-03-01

The repeated dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect liver carcinogens, and this assay could be integrated into general toxicological studies. In this study, in order to assess the performance of the assay, cyclophosphamide monohydrate (CP) was tested in a 14-day RDLMN assay. Based on the results of the 4-day repeated dose-finding study, 10 mg/kg/day of CP was selected as the highest dose and the lower doses were set at 5, 2.5, 1.25, and 0.625 mg/kg/day for the 14-day RDLMN assay. On the day after the completion of the dosing period, specimens of hepatocytes and bone marrow cells were prepared and the induction of micronuclei was assessed. No changes were observed in the incidences of micronucleated hepatocytes. Nevertheless, the incidences of micronucleated immature erythrocytes in the bone marrow were increased significantly at CP doses of 1.25 mg/kg/day or more. These findings are consistent with reports that CP induces tumors in various tissues but it does not induce liver tumors.

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.

Absence of micronucleus formation in CHO-K1 cells cultivated in platelet lysate enriched medium.

Science.gov (United States)

Bernardi, Martina; Adami, Valentina; Albiero, Elena; Madeo, Domenico; Rodeghiero, Francesco; Astori, Giuseppe

2014-03-01

Human platelet lysate (PL) represents an effective substitute of fetal bovine serum (FBS) for mesenchymal stromal cell (MSC) cultivation. Compared to FBS, PL favors MSC proliferation significantly shortening the population doubling time and avoiding the risks related to the use of animal derivatives. Growth factors contained in the platelets are released upon platelet disruption following freezing/thawing cycles or as we have recently described by using ultrasound. We have investigated whether the increased cell proliferation achieved by using PL could induce mitotic stress and whether the potential formation of free radicals during PL production by ultrasound could cause chromosomal instability in mammalian cells. We have applied an image analysis assisted high content screening (HCS) in vitro micronucleus assay in the Chinese Hamster Ovarian K1 (CHO-K1) rodent mammalian cell line. PL was produced by sonication; for the micronucleus assay, CHO-K1 cells were exposed to increasing concentrations of PL. Cytokinesis was blocked by cytochalasin B, nuclei were stained with bisbenzimide and images were acquired and analyzed automatically using an HCS system, both with a 20× and a 10× objective. Our results suggest that growth stimulus induced by the use of PL did not significantly increase micronucleus formation in CHO-K1 cells compared to negative control. Micronucleus testing in conjunction with HCS could represent a valid tool to evaluate the safety of ancillary materials used in the production of cell-based medicinal products. Copyright © 2013 Elsevier GmbH. All rights reserved.

Comparative Erythrocytes Osmotic Fragility Test and some ...

African Journals Online (AJOL)

Erythrocytes osmotic fragility and haematological parameters of subjects with HbAS (sickle cell trait) and HbSS (sickle cell anaemia) were determined and compared with subjects with HbAA (normal adult haemoglobin), which acted as control. They were divided into three groups of 40 subjects for HbAA, 35 subjects for ...

Genotoxicity assessment of cobalt chloride in Eisenia hortensis earthworms coelomocytes by comet assay and micronucleus test.

Science.gov (United States)

Ciğerci, İbrahim Hakkı; Ali, Muhammad Muddassir; Kaygısız, Şöhret Yüksek; Liman, Recep

2016-02-01

Cobalt and its different compounds are extensively used worldwide and considered as possible environmental pollutant. Earthworms are useful model organism and its different species are used to monitor soil pollution. No study has been found to detect cobalt chloride (CoCl2) genotoxicity in earthworms. So, current study aimed to evaluate CoCl2 induced genotoxicity in Eisenia hortensis earthworms coelomocytes by alkaline comet assay (CA) and micronucleus (MN) test. The earthworms (n = 10 for each group) were exposed to different series of CoCl2 concentrations (100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm) to find LD50. The LD50 for CoCl2 was found at 226 ppm. Then, doses of LD50/2, LD50 and 2XLD50 for 48 h were used. CA and MN demonstrated the significant increase (P earthworms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Hyperthermia-induced micronucleus formation in a human keratinocyte cell line

International Nuclear Information System (INIS)

Hintzsche, Henning; Riese, Thorsten; Stopper, Helga

2012-01-01

Elevated temperature can cause biological effects in vitro and in vivo. Many studies on effects of hypo- and hyperthermia have been conducted, but only few studies systematically investigated the formation of genomic damage in the micronucleus test in human cells in vitro as a consequence of different temperatures. In the present study, HaCaT human keratinocytes were exposed to different temperatures from 37 °C to 42 °C for 24 h in a regular cell culture incubator. Micronucleus frequency as a marker of genomic damage was elevated in a temperature-dependent and statistically significant manner. Apoptosis occurred at temperatures of 39 °C or higher. Cell proliferation was unaffected up to 40 °C and decreased at 41 °C and 42 °C. Expression of the heat shock protein Hsp70 was elevated, particularly at temperatures of 40 °C and higher. These findings are in agreement with several in vivo studies and some in vitro studies looking at single, specific temperatures, but a systematically investigated temperature-dependent increase of genomic damage in human keratinocytes in vitro is demonstrated for the first time here.

Lack of genotoxicity of potassium iodate in the alkaline comet assay and in the cytokinesis-block micronucleus test. Comparison to potassium bromate.

Science.gov (United States)

Poul, J M; Huet, S; Godard, T; Sanders, P

2004-02-01

Iodine could be added to the diet of human population in the form of iodide or iodate but iodate had not been adequately tested for genotoxicity and carcinogenicity. In the present study, genotoxic effects of potassium iodate were evaluated in vitro using the alkaline comet assay and the cytokinesis-block micronucleus assay on CHO cells and compared to halogenate salt analogues potassium bromate and chlorate and also to their respective reduced forms (potassium iodide, bromide and chloride). The results showed that the comet assay failed to detect the presence of DNA damage after a treatment of cells by potassium iodate for concentrations up to 10 mM. This absence of primary DNA damage was confirmed in the cytokinesis-block micronucleus assay. In the same way, results showed that potassium chlorate as well as potassium iodide, bromide and chloride did not induced DNA damage in the alkaline comet assay for doses up to 10 mM. By contrast, potassium bromate exposure led to an increase in both DNA damage and frequency of micronucleated cells. The repair of bromate-induced DNA damage was incomplete 24 h after the end of treatment. These results seem to indicate that potassium bromate would induce DNA damage by several mechanisms besides oxidative stress.

The cytokinesis-block micronucleus assay: a sensitive technique for measuring radiation-induced chromosome damage

International Nuclear Information System (INIS)

Fenech, M.; Morley, A.A.

1987-01-01

The sensitivity of the cytokinesis-block micronucleus assay was demonstrated by the detection in human lymphocytes of in vitro exposures of as low as 0.02 Gy of X-rays. To determine the suitability of this new method for measuring in vivo exposure to radiation the authors have performed initial longitudinal studies on (a) cancer patients undergoing partial body fractionated radiotherapy and (b) BALB-C mice following in vivo whole body irradiation with acute single doses of X-rays. The results for radiotherapy patients indicate that the dose fractions have an additive effect on the observed micronucleus frequency which appeared to decline following three months after completion of therapy. Results with irradiated mice showed a sharp increase in micronucleus frequency for splenocytes sampled immediately after treatment and the rate of decline in micronucleus frequency during the first week after treatment was dose-dependent. (author)

Use of micronucleus test in the assessment of radiation effects in aquatic environments

International Nuclear Information System (INIS)

Araujo, Edvaldo F. de; Silva, Luanna R.S.; Lima, Pedro A. de S.; Amancio, Francisco F.; Melo, Ana Maria M. de A.; Silva, Edvane B. da; Silva, Ronaldo C. da

2011-01-01

The study of the effects of radioactive substances on the environment is accomplished by radioecology. This science has played an important role in combating all forms of pollution. The uncontrolled use of physical and chemical agents has been a concern for environmental regulatory agencies, due to the serious damage to ecosystems. Aquatic organisms are exposed to a variety of pollutants harmful to aquatic systems. The mollusks Biomphalaria glabrata has been featured as a bioindicator to possess characteristics such as short reproductive cycle ease of maintenance in the laboratory and low maintenance cost. The micronucleus assay has been shown to be a great test to identify mutagenic effects caused by physical and chemical agents. In this study the frequency of micronuclei in haemocytes of Biomphalaria glabrata exposed to high doses of 60 Co gamma radiation contributing to a further standardization of this test as an indicator of the presence of radioactive contamination in aquatic environments. The young adult snails of Biomphalaria glabrata were divided into groups and subjected to a dose of 0 (control), 40 and 60 Gy of gamma radiation. The results showed that snails irradiated with 40 Gy showed a smaller number of haemocytes, whereas those exposed to 60 Gy had a greater quantity of these cells compared to control group. It can be concluded that the morphological analysis and the frequency of micronuclei in haemocytes of Biomphalaria glabrata exposed to 60 Co gamma radiation may be used in studies of the action of high doses of radiation in aquatic environments (author)

Micronucleus assay as a biomarker of genotoxicity in the occupational exposure to agrochemicals in rural workers.

Science.gov (United States)

Gentile, N; Mañas, F; Bosch, B; Peralta, L; Gorla, N; Aiassa, D

2012-06-01

This paper aims to evaluate the genotoxic effect of agrochemicals in rural workers occupationally exposed by the micronucleus assay in peripheral blood lymphocytes and to promote the development of health and environmental preventive and protective practices. A total of 30 blood samples from 20 individuals occupationally exposed to different agrochemicals and 10 unexposed persons, who formed the reference group, were analyzed. We found statistically significant differences (p < 0.0005, Student's t Test) in the frequency of micronuclei between the two groups (7.20 ± 1.55 and 15.15 ± 5.10 CBMN for reference and exposed groups respectively). The analysis of age showed a positive correlation (Pearson Correlation Test) with the frequency of micronuclei in exposed population (p < 0.05; r(2) = 0.47), in contrast with smoking habits and years of exposure. Micronucleus assay allows an early detection of populations at higher risk of having genetic damage, allowing us to implement strategies of intervention for the purpose of contributing to reduce that risk.

Assessment of mutagenic, antimutagenic and genotoxicity effects of Mimosa tenuiflora

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Viviane A. Silva

2013-02-01

Full Text Available Genotoxic effects of Mimosa tenuiflora (Willd. Poir, Fabaceae, were investigated by using both micronucleus test and bacterial reverse mutation assay in Salmonella typhimurium TA97, TA98, TA100, TA102 respectively. In respect of Ames test results show that the extract does not induce mutations in any strains of Salmonella typhimurium tested since the mutagenicity index is less than 2. In the antimutagenic effect was observed that the extract at the concentrations tested significantly decreased the mutagenicity index of all strains tested which characterized the extract as antimutagenic in these conditions. In the micronucleus test in vivo, we observed that the concentrations used did not induce an increase in the frequency of micronucleus in normochromatic erythrocytes of mice. Therefore, we concluded that the extract of M. tenuiflora is not mutagenic in the absence of exogenous metabolizing system and does not induce an increase in the frequency of the micronucleus characterized as an agent not mutagenic in these conditions. Further studies of toxicity need to be made to the use of this plant in the treatment of diseases to be stimulated.

Assessment of mutagenic, antimutagenic and genotoxicity effects of Mimosa tenuiflora

Directory of Open Access Journals (Sweden)

Viviane A. Silva

2013-04-01

Full Text Available Genotoxic effects of Mimosa tenuiflora (Willd. Poir, Fabaceae, were investigated by using both micronucleus test and bacterial reverse mutation assay in Salmonella typhimurium TA97, TA98, TA100, TA102 respectively. In respect of Ames test results show that the extract does not induce mutations in any strains of Salmonella typhimurium tested since the mutagenicity index is less than 2. In the antimutagenic effect was observed that the extract at the concentrations tested significantly decreased the mutagenicity index of all strains tested which characterized the extract as antimutagenic in these conditions. In the micronucleus test in vivo, we observed that the concentrations used did not induce an increase in the frequency of micronucleus in normochromatic erythrocytes of mice. Therefore, we concluded that the extract of M. tenuiflora is not mutagenic in the absence of exogenous metabolizing system and does not induce an increase in the frequency of the micronucleus characterized as an agent not mutagenic in these conditions. Further studies of toxicity need to be made to the use of this plant in the treatment of diseases to be stimulated.

In vivo micronucleus test as a biomarker of genotoxicity in free-range goats from suspected contaminated environment

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Afusat Jagun Jubril

2017-09-01

Conclusion: The finding indicates the prevalence and frequency of micronucleus as a biomarker of genotoxicity and an indicator of exposure to environmental genotoxic subtances. Hence, this highlights the relevance of these goats as important sentinel animal model. These findings, therefore, serve as a preliminary data for further studies on the latent genotoxic environmental contaminants and their potential deleterious impact. [J Adv Vet Anim Res 2017; 4(3.000: 281-287

EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2015. Scientific Opinion on Flavouring Group Evaluation 208 Revision 1 (FGE.208Rev1): Consideration of genotoxicity data on representatives for 10 alicyclic aldehydes with the a,b-unsaturation in ring / side-chain and precursors from chemical subgroup 2.2 of FGE.19

DEFF Research Database (Denmark)

Beltoft, Vibe Meister; Nørby, Karin Kristiane

genotoxicity studies on p-mentha-1,8-dien-7-al [FL-no: 05.117], the representative substance for FGE.19 subgroup 2.2. This substance was tested in vivo in a combined micronucleus assay in bone marrow and Comet assay in liver and duodenum. It did not induce any increase in micronucleated polychromatic...... erythrocytes of the bone marrow of male rats in the micronucleus test and it did not induce DNA damage in duodenum of the same animals as analysed by the Comet assay. The Comet assay performed in liver shows a positive result and therefore the Panel concluded that p-mentha-1,8-dien-7-al [FL-no: 05...

Evaluation of the repeated-dose liver and gastrointestinal tract micronucleus assays with 22 chemicals using young adult rats: summary of the collaborative study by the Collaborative Study Group for the Micronucleus Test (CSGMT)/The Japanese Environmental Mutagen Society (JEMS) - Mammalian Mutagenicity Study Group (MMS).

Science.gov (United States)

Hamada, Shuichi; Ohyama, Wakako; Takashima, Rie; Shimada, Keisuke; Matsumoto, Kazumi; Kawakami, Satoru; Uno, Fuyumi; Sui, Hajime; Shimada, Yasushi; Imamura, Tadashi; Matsumura, Shoji; Sanada, Hisakazu; Inoue, Kenji; Muto, Shigeharu; Ogawa, Izumi; Hayashi, Aya; Takayanagi, Tomomi; Ogiwara, Yosuke; Maeda, Akihisa; Okada, Emiko; Terashima, Yukari; Takasawa, Hironao; Narumi, Kazunori; Wako, Yumi; Kawasako, Kazufumi; Sano, Masaki; Ohashi, Nobuyuki; Morita, Takeshi; Kojima, Hajime; Honma, Masamitsu; Hayashi, Makoto

2015-03-01

The repeated-dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect hepatocarcinogens. We conducted a collaborative study to assess the performance of this assay and to evaluate the possibility of integrating it into general toxicological studies. Twenty-four testing laboratories belonging to the Mammalian Mutagenicity Study Group, a subgroup of the Japanese Environmental Mutagen Society, participated in this trial. Twenty-two model chemicals, including some hepatocarcinogens, were tested in 14- and/or 28-day RDLMN assays. As a result, 14 out of the 16 hepatocarcinogens were positive, including 9 genotoxic hepatocarcinogens, which were reported negative in the bone marrow/peripheral blood micronucleus (MN) assay by a single treatment. These outcomes show the high sensitivity of the RDLMN assay to hepatocarcinogens. Regarding the specificity, 4 out of the 6 non-liver targeted genotoxic carcinogens gave negative responses. This shows the high organ specificity of the RDLMN assay. In addition to the RDLMN assay, we simultaneously conducted gastrointestinal tract MN assays using 6 of the above carcinogens as an optional trial of the collaborative study. The MN assay using the glandular stomach, which is the first contact site of the test chemical when administered by oral gavage, was able to detect chromosomal aberrations with 3 test chemicals including a stomach-targeted carcinogen. The treatment regime was the 14- and/or 28-day repeated-dose, and the regime is sufficiently promising to incorporate these methods into repeated-dose toxicological studies. The outcomes of our collaborative study indicated that the new techniques to detect chromosomal aberrations in vivo in several tissues worked successfully. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

International Nuclear Information System (INIS)

Boreham, D.R.; Dolling, J.-A.; Maves, S.R.; Siwarungsun, N.; Mitchel, R.E.J.

2000-01-01

We have compared dose-rate effects for γ-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

Dose-rate effects for apoptosis and micronucleus formation in gamma-irradiated human lymphocytes

Energy Technology Data Exchange (ETDEWEB)

Boreham, D.R.; Dolling, J.-A.; Maves, S.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Siwarungsun, N. [Chulalongkorn Univ., Bangkok (Thailand); Mitchel, R.E.J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2000-07-01

We have compared dose-rate effects for {gamma}-radiation-induced apoptosis and micronucleus formation in human lymphocytes. Long-term assessment of individual radiation-induced apoptosis showed little intraindividual variation but significant interindividual variation. The effectiveness of radiation exposure to cause apoptosis or micronucleus formation was reduced by low-dose-rate exposures, but the reduction was apparent at different dose rates for these two end points. Micronucleus formation showed a dose-rate effect when the dose rate was lowered to 0.29 cGy/min, but there was no accompanying cell cycle delay. A further increase in the dose-rate effect was seen at 0.15 cGy/min, but was now accompanied by cell cycle delay. There was no dose-rate effect for the induction of apoptosis until the dose rate was reduced to 0.15 cGy/min, indicating that the mechanisms or signals for processing radiation-induced lesions for these two end points must be different at least in part. There appear to be two mechanisms that contribute to the dose-rate effect for micronucleus formation. One of these does not affect binucleate cell frequency and occurs at dose rates higher than that required to produce a dose-rate effect for apoptosis, and one affects binucleate cell frequency, induced only at the very low dose rate which coincidentally produces a dose-rate effect for apoptosis. Since the dose rate at which cells showed reduced apoptosis as well as a further reduction in micronucleus formation was very low, we conclude that the processing of the radiation-induced lesions that induce apoptosis, and some micronuclei, is very slow in quiescent and PHA-stimulated lymphocytes, respectively. (author)

Test of micronucleus in lymphocytes with the cytokinesis-block like possible indicator of the answer of the patient to the radiotherapy

International Nuclear Information System (INIS)

Giorgio, Marina di; Nasazzi, Nora; Taja, Maria R.; Roth, Berta; Sardi, Mabel; Menendez, Pablo R.

2001-01-01

In order to evaluate the individual cytogenetic response to radiotherapy and its comparison with the clinical response, the cytokinesis-block micronucleus assay was applied to peripheral blood lymphocytes of patients with cervix cancer undergoing radiotherapy. The cytogenetic data were analysed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogenetic recovery factor (k) that might correlate with the individual radiosensitivity, contributing with radiosensitivity tests of current use but applying a rapid methodology easy to implement in a routine clinical laboratory. Long term clinical observations could confirm the validity of k in expressing predisposition of the subject to develop delayed effects. (author)

Biomonitoring of Serbian population revealed by CB micronucleus test before and after the bombing of Yugoslavia

International Nuclear Information System (INIS)

Joksic, G.; Stankovic, M.; Guc-Scekic, M.; Vranjes, A.

2002-01-01

The induction of micronuclei in mitotically active cells has been widely used and promoted as a biological marker of exposure to environmental toxins. Biomonitoring of population using cytochalasin block micronucleus test (CBMN) has been performed for 11 years in our country; the incidence of micronuclei was evaluated in many groups of occupationally exposed persons as well as healthy unexposed controls. The spontaneous frequency of MN per 1000 binucleated cells was 9±3 (mean±SD) for woman, 7±2 for men. The average incidence of micronuclei in lymphocytes of newborns was 5.3±0.6, in their mothers 15±3 per 1000 binucleated cells, respectively. After the bombing of Yugoslavia significantly higher incidence of micronuclei was found in all groups of examines: health adults and newborns. In healthy adults, the average incidence of micronuclei was 28.16±14.63; in young pregnant woman 25.3±5.02 and their foetuses 20.14±9.6 respectively. One year latter (2001) the incidence of MN declined in all adults but enhance in foetal blood lymphocytes. (author)

Micronucleus formation in cultured human keratinocytes: Involvement of intercellular bioactivation.

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van Pelt, F N; Haring, R M; Weterings, P J

1991-01-01

Micronucleus formation in cultured human keratinocytes was studied after exposure to benzo[a]pyrene, cyclophosphamide and 12-O-tetradecanoylphorbol-13-acetate without the addition of an exogenous metabolizing system. The first two agents need bioactivation by specific isoenzymes of cytochrome P-450 to form genotoxic intermediates. Benzo[a]pyrene induced the micronucleus formation in both uninduced and Aroclor 1254-pretreated cultures. Clastogenic effects of cyclophosphamide were observed only in Aroclor 1254-pretreated cells. The tumour promotor 12-O-tetradecanoylphorbol-13-acetate did not affect the frequency of micronuclei in human keratinocytes. The data indicate that cultured human keratinocytes can be used to study the tissue-specific response to genotoxic agents as well as interindividual variation in biotransformation capacity.

Evaluation of micronuclei in mice bone marrow and antioxidant systems in erythrocytes exposed to α-amanitin.

Science.gov (United States)

Marciniak, B; Lopaczyńska, D; Kowalczyk, E; Skośkiewicz, J; Witczak, M; Majczyk, M; Grabowicz, W; Ferenc, T

2013-03-01

α-Amanitin, the main toxic substance from mushroom species (Amanita genus), blocks the activity of RNA polymerase II (Pol II) in mammalian cells causing inhibition of transcription and subsequent synthesis of structural and enzymatic proteins. It has been postulated that α-amanitin generates the increase of reactive oxygen species (ROS) concentration. The micronucleus (MN) test was used on an animal experimental model to evaluate possible potential genotoxic effect of α-amanitin on mice bone marrow cells. At the same time the activity of antioxidant enzymes: superoxide dismutase (SOD) and catalase (CAT) as well as concentration of thiobarbituric acid reactive substance (TBARS) were investigated in the lysate of mice erythrocytes. α-Amanitin was administered intraperitoneally at the doses: 0.1, 0.15, and 0.25 mg/kg bw (LD(50) for mice) 48 h prior to sacrification. A statistically significant increase of SOD activity was observed in the hemolysate for all the investigated α-amanitin doses as compared to the negative control (p activity for α-amanitin doses 0.1 and 0.15 mg/kg was higher in comparison to the negative control but the differences were not statistically significant (p > 0.05). However, for the dose 0.25 mg/kg the activity of CAT was statistically significantly higher (p  0.05). A statistically significant increase of mean values of MN percent was found in polychromatic erythrocytes (PCEs) as compared to the negative control for α-amanitin dose 0.1 and 0.25 mg/kg (p  0.1). The observed disturbances in the activity of the examined antioxidant enzymes in cells exposed in vivo to α-amanitin suggest indirect genotoxic effect of α-amanitin through ROS generation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Study on the mutagenic effects of a new chelating agent (7603) used for accelerating excretion of radionuclides

International Nuclear Information System (INIS)

Shen Binyuan; Luo Meichu; Zhen Guibao; Ruan Tianming; Feng Jialin; Cao Qunli

1989-01-01

The results of studies on the mutagenic effects of a new chelating agent, Suo An Quan (7603) or 5-methxlene Iminodiaeticaid Vanillin, was reported in this paper. For this agent, no mutagenesis was found by the reverse mutation test of Salmonella typhi munine (Amos test), the test of chromosome aberrations in Chinese hamster oocytes (CHO cells), and the test of micronucleus in polychromatic erythrocytes of the bone marrow in mice

The radioprotective potential of 3,5,4'-trihydroxystilbene

International Nuclear Information System (INIS)

Clemente, Mary Judith Q.; Gomez, Marlyn O.

1999-03-01

The radioprotective potential of 3,5,4'trihydroxystilbene or resveratrol, a compound abundant in grapes, was investigated using the micronucleus test. Gamma radiation (6 Gy) was used to induce micronucleus formation in 12-week old Swiss-Webster mice. Five groups with five mice each were used. Three groups were given corresponding treatments (low, normal, high doses of reservatrol) via oral gavage for one week. The negative control group was not given any radiation nor any compound while the positive control group was exposed to radiation but was not given any compound. The mean micronucleus frequencies arranged from highest to lowest are as follows: low dose, positive control, normal dose, high dose and negative control. Using the analysis of variance-complete random design followed by the Duncan multiple range test, it was proven that resveratrol was able to inhibit micronucleus formation in polychromatic erythrocytes of 12-week old Swiss-Webster mice at the normal (60 micrograms) and high (120 micrograms) concentrations assigned. This suggests that its radioprotective potential may follow a dose-dependent pattern. (Author)

In vitro mutagenicity and genotoxicity study of 1,2-dichloroethylene, 1,1,2-trichloroethane, 1,3-dichloropropane, 1,2,3-trichloropropane and 1,1,3-trichloropropene, using the micronucleus test and the alkaline single cell gel electrophoresis technique (comet assay) in human lymphocytes.

Science.gov (United States)

Tafazoli, M; Kirsch-Volders, M

1996-12-20

The main objective of this study was to compare the cytotoxic genotoxic and mutagenic activity of a number of chlorinated aliphatic hydrocarbons, which are widely used as chemical intermediates, solvents, degreasing agents etc. in industry, and to establish the structure-toxicity relationship of the chemicals by using the most adequate determinants in estimating their toxicity. The mutagenicity and cytotoxicity of some of the candidate chemicals, namely 1,2-dichloroethylene, 1,1,2-trichloroethane, 1,3-dichloropropane, 1,2,3-trichloropropane and 1,1,3-trichloropropene were evaluated in an in vitro micronucleus assay. The cytokinesis-block methodology was applied on human lymphocytes in the presence or absence of an external metabolic activation system (S9-mix). In the micronucleus assay, all test substances, except 1,2,3-trichloropropane with and without S9-mix and 1,1,2-trichloroethane without S9-mix in the repeated experiment, exhibited a low but statistically significant mutagenic activity, compared to the concurrent control. However, none of the five chemicals was able to induce a clear and reproducible linear dose-dependent increase in micronucleus frequencies in this assay. Generally, mutagenic activity of the chemicals was found in the absence of severe cytotoxicity and/or cell cycle delay. The DNA breakage capacity and the cytotoxicity of these chemicals were also assessed in the alkaline single cell gel (SCG) electrophoresis test (comet assay) with and without S9-mix in isolated human lymphocytes. All chemical compounds induced DNA breakage, in the presence or absence of the metabolic activation system, at the doses tested. The data showed that the DNA reactivity of the chemicals increased with increasing degree of halogenation. The results of the present work suggested that the comet assay might be a more suitable and sensitive screening method than the micronucleus test for this particular class of compound. However, both assays do detect different

Mutagenicity of the Musa paradisiaca (Musaceae) fruit peel extract in mouse peripheral blood cells in vivo.

Science.gov (United States)

Andrade, C U B; Perazzo, F F; Maistro, E L

2008-01-01

Plants are a source of many biologically active products and nowadays they are of great interest to the pharmaceutical industry. In the present study, the mutagenic potential of the Musa paradisiaca fruit peel extract was assessed by the single-cell gel electrophoresis (SCGE) and micronucleus assays. Animals were treated orally with three different concentrations of the extract (1000, 1500, and 2000 mg/kg body weight). Peripheral blood cells of Swiss mice were collected 24 h after treatment for the SCGE assay and 48 and 72 h for the micronucleus test. The results showed that the two higher doses of the extract of M. paradisiaca induced statistically significant increases in the average numbers of DNA damage in peripheral blood leukocytes for the two higher doses and a significant increase in the mean of micronucleated polychromatic erythrocytes in the three doses tested. The polychromatic/normochromatic erythrocyte ratio scored in the treated groups was not statistically different from the negative control. The data obtained indicate that fruit peel extract from M. paradisiaca showed mutagenic effect in the peripheral blood cells of Swiss albino mice.

Morphometric analysis of erythrocytes from patients with thalassemia using tomographic diffractive microscopy

Science.gov (United States)

Lin, Yang-Hsien; Huang, Shin-Shyang; Wu, Shang-Ju; Sung, Kung-Bin

2017-11-01

Complete blood count is the most common test to detect anemia, but it is unable to obtain the abnormal shape of erythrocytes, which highly correlates with the hematologic function. Tomographic diffractive microscopy (TDM) is an emerging technique capable of quantifying three-dimensional (3-D) refractive index (RI) distributions of erythrocytes without labeling. TDM was used to characterize optical and morphological properties of 172 erythrocytes from healthy volunteers and 419 erythrocytes from thalassemic patients. To efficiently extract and analyze the properties of erythrocytes, we developed an adaptive region-growing method for automatically delineating erythrocytes from 3-D RI maps. The thalassemic erythrocytes not only contained lower hemoglobin content but also showed doughnut shape and significantly lower volume, surface area, effective radius, and average thickness. A multi-indices prediction model achieved perfect accuracy of diagnosing thalassemia using four features, including the optical volume, surface-area-to-volume ratio, sphericity index, and surface area. The results demonstrate the ability of TDM to provide quantitative, hematologic measurements and to assess morphological features of erythrocytes to distinguish healthy and thalassemic erythrocytes.

Micronucleus induction by repeated exposure of diagnostic X-ray on oral buccal mucosa

International Nuclear Information System (INIS)

Lohith Tejashvi, K.; Suchetha Kumari, N.; Shetty, Shishir Ram

2012-01-01

Radiography is the important diagnostic tools essential for diagnosis and planning of orthodontic treatment. X-ray is ionizing radiation which showed various effects include breaking the bond of biological molecules, inducing loss of ability of cell death, increases nuclear alterations. Micronuclei - x000D - (MN) are small chromatin bodies that appear in the cytoplasm by the - x000D - condensation of acrocentric chromosomal fragments or by whole chromosomes. This - x000D - is a sensitive indicator of genetic damage. - x000D - x000D - . To evaluate micronucleus induction by repeated exposure of diagnostic X-ray on human buccal cell. Methods: 25 patients who visiting to ABSMIDS, Department of Oral medicine and Radiology for dental checkup exposed to diagnostic X-ray more than 4 times have been selected for this study. The buccal cell for analysis was collected from the cheek mucosa by means of gentle scraping of epithelial using ice-cream sticks and placed in Buffer saline. This sample was smeared on glass slide and then fixed in methanol:glacial acetic acid (3:1). Air dried and stained with Giemsa for 15-25 minutes. Then 250 cells in each slides were analyzed under microscope and frequency of micronucleus was scored (n=4). Repeated X-ray exposed cells showed micronucleus (1.25%) and nuclear alteration (2.3%) compare to the control. Repeated X-ray exposure leads to induces detectable number of micronucleus and nuclear alterations. (author)

Histopathological and genotoxic effects of chlorpyrifos in rats.

Science.gov (United States)

Ezzi, Lobna; Belhadj Salah, Imen; Haouas, Zohra; Sakly, Amina; Grissa, Intissar; Chakroun, Sana; Kerkeni, Emna; Hassine, Mohsen; Mehdi, Meriem; Ben Cheikh, Hassen

2016-03-01

This study aims to investigate the effects of chlorpyrifos's sub-acute exposure on male rats. Two groups with six animals each were orally treated, respectively, with 3.1 mg/kg b w and 6.2 mg/kg b w of chlorpyrifos during 4 weeks. The genotoxic effect of chlopyrifos was investigated using the comet assay and the micronucleus test. Some hematological and liver's histopathological changes were also evaluated. Results revealed that chlorpyrifos induced histopathological alterations in liver parenchyma. The lymphoid infiltration observed in liver sections and the increase in white blood cells parameter are signs of inflammation. A significant increase in the platelet' count and in polychromatic erythrocytes/normochromatic erythrocytes (PCE/NCE) ratio was observed in chlorpyrifos-treated groups which could be due to the stimulatory effect of chlorpyrifos on cell formation in the bone marrow at lower doses. In addition, the increase of bone marrow micronucleus percentage and the comet tail length revealed a genotoxic potential of chlorpyrifos in vivo.

Combined cytokinesis-block micronucleus and chromosomal aberration assay for the evaluation of radiosensitizers at low radiation doses

International Nuclear Information System (INIS)

Oya, Natsuo; Shibamoto, Yuta; Shibata, Toru

1994-01-01

Several methods have been tried for evaluating the efficacy of hypoxic cell radiosensitizers at clinically relevant low radiation doses (1-4 Gy). The cytokinesis-block micronucleus assay is known to be useful for both the in vitro and in vivo evaluation of radiosensitizers, while the chromosomal aberration assay has been commonly used to assess the mutagenicity of various agents. In the present study, the chromosomal aberration assay and the cytokinesis-block micronucleus assay were performed simultaneously to assess the radiosensitizing effect of etanidazole and KU-2285 at low radiation doses. The correlation between the two assays was also evaluated. In vitro study: EMT-6 cells were irradiated at a dose of 1-3 Gy under hypoxic conditions with or without the drugs at 1 mM. In vivo-in vitro study: EMT-6 tumor-bearing BALB/c mice received 2-4 Gy of radiation with or without administration of the drugs at 200 mg/kg. Single-cell suspensions were then obtained in both studies and were used for the cytokinesis-block micronucleus assay and the chromosomal aberration assay. The micronucleus frequency in binucleate cells was evaluated in the former assay, and the frequency of chromosomal aberrations in metaphase cells was evaluated in the latter assay. In vitro study: the sensitizer enhancement ratios of etanidazole and KU-2285 were 1.73 and 2.21, respectively, in the micronucleus assay, and 1.41 and 1.79 in the chromosomal aberration assay. In vivo-in vitro study: the sensitizer enhancement ratios of etanidazole and KU-2285 were 1.18 and 1.31, respectively, in the micronucleus assay, and 1.16 and 1.42 in the chromosomal aberration assay. In both studies, a linear correlation was observed between the micronucleus frequency and the chromosomal aberration frequency. The background (i.e., the frequency at 0 Gy) of the latter assay was considerably lower than that of the former assay, especially in the in vivo study. 31 refs., 4 figs

Aged garlic extract modulates the oxidative modifications induced by γ-rays in mouse bone marrow and erythrocytes cells

International Nuclear Information System (INIS)

Tawfik, S.S.; Elshamy, E.; Sallam, M.H.

2006-01-01

Gamma-ray generate hydroxyl radicals in cells and induce cellular DNA damage which leads to genotoxicity and chromosomes aberrations. The radioprotective and therapeutic efficacy of aged garlic extract (AGE) was investigated with micronucleus method as a reliable method for the detection of chromosomes damage induced by chemical and radiation. The frequency of micronuclei found in bone marrow erythroblast cells of the Protected and treated groups with 1.0 ml/20 g body wt/day for 10 consecutive days were significantly much lower than that of the exposed groups to γ-irradiation without protection or treatment. In addition, the enzyme activities of mouse erythrocyte antioxidant defense mechanism: superoxide dismutase (SOD), glutathione peroxidase (GSH-P x ) and glutathione reductase (GSH-R) were markedly decreased after irradiation while in protected and treated groups with Age showed significant increase but did not reach the control level except for Gash-R activity of protected group

Decreased erythrocyte superoxide dismutase in elderly men with early nuclear cataract

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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.

Decreased erythrocyte superoxide dismutase in elderly men with early nuclear cataract

Directory of Open Access Journals (Sweden)

Rose

2014-04-01

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.

Analysis of resveratrol and radiation effects in lung cancer cells by micronucleus assay

Energy Technology Data Exchange (ETDEWEB)

Moreno, Carolina S.; Santos, Dymes R.A.; Vieira, Daniel P.; Rogero, Sizue O.; Rogero, Jose R., E-mail: carolina_sm@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Sakuraba, Roberto K.; Weltman, Eduardo [Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Cruz, Aurea S.; Santos, Rezolina P. [Instituto Adolfo Lutz, Sao Paulo, SP (Brazil)

2015-07-01

Mucoepidermoid lung carcinoma is frequently manifested by obstructive trachea symptoms. Radiation and drugs combinations are commonly used in the lung cancer treatment. Currently there is a strong tendency to develop therapeutic strategies focused at the administration of high potential compounds to improve the ionizing radiation treatments, so as to increase the radiation effects on tumor cell while minimizing these effects to surrounding normal tissues. Resveratrol is a polyphenolic phytoalexin compound present in wines and several plants. This compound has a broad spectrum of biological activities such as antioxidant, anticarcinogenic, and induction of cell cycle arrest effects. Analysis of biological effects of ionizing radiation in the presence of resveratrol in different cell cultures has been the subject of many studies. To verify the genotoxic effects in cells exposed to ionizing radiation many methods have been proposed. The cytokinesis-block micronucleus technique is one of the preferred methods. The main of this study was to detect and quantify radioinduced DNA damage in mucoepidermoid lung carcinoma cells (NCI-H292) by cytokinesis-block micronucleus technique using cytocalasin-B. The cell culture was irradiated at a single fraction from a TrueBeam® linear accelerator (0, 0.8, 5, and 10 Gy), in the absence or presence of different resveratrol concentrations (0, 15, 30, and 60 μM). The results showed that resveratrol (15 and μM) induced significant increase frequency (p<0.05) of micronucleus formation in NCI-H292 cell culture non-irradiated and exposed at 5 Gy dose. Moreover, resveratrol (30 μM) induced micronucleus formation at 0.8 Gy dose. (author)

Analysis of resveratrol and radiation effects in lung cancer cells by micronucleus assay

International Nuclear Information System (INIS)

Moreno, Carolina S.; Santos, Dymes R.A.; Vieira, Daniel P.; Rogero, Sizue O.; Rogero, Jose R.; Sakuraba, Roberto K.; Weltman, Eduardo; Cruz, Aurea S.; Santos, Rezolina P.

2015-01-01

Mucoepidermoid lung carcinoma is frequently manifested by obstructive trachea symptoms. Radiation and drugs combinations are commonly used in the lung cancer treatment. Currently there is a strong tendency to develop therapeutic strategies focused at the administration of high potential compounds to improve the ionizing radiation treatments, so as to increase the radiation effects on tumor cell while minimizing these effects to surrounding normal tissues. Resveratrol is a polyphenolic phytoalexin compound present in wines and several plants. This compound has a broad spectrum of biological activities such as antioxidant, anticarcinogenic, and induction of cell cycle arrest effects. Analysis of biological effects of ionizing radiation in the presence of resveratrol in different cell cultures has been the subject of many studies. To verify the genotoxic effects in cells exposed to ionizing radiation many methods have been proposed. The cytokinesis-block micronucleus technique is one of the preferred methods. The main of this study was to detect and quantify radioinduced DNA damage in mucoepidermoid lung carcinoma cells (NCI-H292) by cytokinesis-block micronucleus technique using cytocalasin-B. The cell culture was irradiated at a single fraction from a TrueBeam® linear accelerator (0, 0.8, 5, and 10 Gy), in the absence or presence of different resveratrol concentrations (0, 15, 30, and 60 μM). The results showed that resveratrol (15 and μM) induced significant increase frequency (p<0.05) of micronucleus formation in NCI-H292 cell culture non-irradiated and exposed at 5 Gy dose. Moreover, resveratrol (30 μM) induced micronucleus formation at 0.8 Gy dose. (author)

Kinetics of micronucleus induction and cytotoxicity caused by distinct antineoplastics and alkylating agents in vivo.

Science.gov (United States)

Morales-Ramírez, Pedro; Vallarino-Kelly, Teresita; Cruz-Vallejo, Virginia

2014-01-30

This mini-review aims to compare the differences in the kinetics of the induction of micronucleated polychromatic erythrocytes (MN-PCE) and cytotoxicity by distinct antineoplastic and genotoxic agents in murine peripheral blood in vivo and to correlate these kinetics with the underlying processes. Comparisons were carried out using our previously obtained data with nominal doses causing similar levels of cytotoxicity, as measured in terms reduction of PCE. The aneuploidogens caused the most rapid induction of MN-PCEs and had the highest rates of cytotoxicity and genotoxicity. The promutagens cyclophosphamide and dimethylnitrosamine showed the most delayed responses and had the lowest genotoxic and cytotoxic efficiencies. DNA crosslinking agents had a similar delay of 4-5 h, greater than those of aneuploidogens, but differed in their cytotoxic and genotoxic efficiencies. Methylnitrosourea and 5-aza-cytidine caused greater delays than crosslinking agents. These delays can be due to the methylnitrosourea-mediated induction of formation of mono alkyl adducts which are interpreted as mismatches during DNA duplication, whereas 5-aza-cytidine requires incorporation into the DNA to induce breakage. This review allows us to conclude that the requirement for metabolic activation and the mechanisms of DNA breakage and of micronucleus induction are the main factors that affect the time of maximal MN-PCE induction. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Influence of Erythrocyte Membrane Stability in Atherosclerosis.

Science.gov (United States)

da Silva Garrote-Filho, Mario; Bernardino-Neto, Morun; Penha-Silva, Nilson

2017-04-01

The purpose of this study is to show how an excess of cholesterol in the erythrocyte membrane contributes stochastically to the progression of atherosclerosis, leading to damage in blood rheology and O 2 transport, deposition of cholesterol (from trapped erythrocytes) in an area of intraplaque hemorrhage, and local exacerbation of oxidative stress. Cholesterol contained in the membrane of erythrocytes trapped in an intraplaque hemorrhage contributes to the growth of the necrotic nucleus. There is even a relationship between the amount of cholesterol in the erythrocyte membrane and the severity of atherosclerosis. In addition, the volume variability among erythrocytes, measured by RDW, is predictive of a worsening of this disease. Erythrocytes contribute to the development of atherosclerosis in several ways, especially when trapped in intraplate hemorrhage. These erythrocytes are oxidized and phagocytosed by macrophages. The cholesterol present in the membrane of these erythrocytes subsequently contributes to the growth of the atheroma plaque. In addition, when they rupture, erythrocytes release hemoglobin, which leads to the generation of free radicals. Finally, increased RDW may predict the worsening of atherosclerosis, due to the effects of inflammation and oxidative stress on erythropoiesis and erythrocyte volume. A better understanding of erythrocyte participation in atherosclerosis may contribute to the improvement of the prevention and treatment strategies of this disease.

Dielectric inspection of erythrocyte morphology

International Nuclear Information System (INIS)

Hayashi, Yoshihito; Oshige, Ikuya; Katsumoto, Yoichi; Omori, Shinji; Yasuda, Akio; Asami, Koji

2008-01-01

We performed a systematic study of the sensitivity of dielectric spectroscopy to erythrocyte morphology. Namely, rabbit erythrocytes of four different shapes were prepared by precisely controlling the pH of the suspending medium, and their complex permittivities over the frequency range from 0.1 to 110 MHz were measured and analyzed. Their quantitative analysis shows that the characteristic frequency and the broadening parameter of the dielectric relaxation of interfacial polarization are highly specific to the erythrocyte shape, while they are insensitive to the cell volume fraction. Therefore, these two dielectric parameters can be used to differentiate erythrocytes of different shapes, if dielectric spectroscopy is applied to flow-cytometric inspection of single blood cells. In addition, we revealed the applicability and limitations of the analytical theory of interfacial polarization to explain the experimental permittivities of non-spherical erythrocytes

Dielectric inspection of erythrocyte morphology

Energy Technology Data Exchange (ETDEWEB)

Hayashi, Yoshihito; Oshige, Ikuya; Katsumoto, Yoichi; Omori, Shinji; Yasuda, Akio [Life Science Laboratory, Materials Laboratories, Sony Corporation, Sony Bioinformatics Center, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510 (Japan); Asami, Koji [Laboratory of Molecular Aggregation Analysis, Division of Multidisciplinary Chemistry, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)], E-mail: Yoshihito.Hayashi@jp.sony.com

2008-05-21

We performed a systematic study of the sensitivity of dielectric spectroscopy to erythrocyte morphology. Namely, rabbit erythrocytes of four different shapes were prepared by precisely controlling the pH of the suspending medium, and their complex permittivities over the frequency range from 0.1 to 110 MHz were measured and analyzed. Their quantitative analysis shows that the characteristic frequency and the broadening parameter of the dielectric relaxation of interfacial polarization are highly specific to the erythrocyte shape, while they are insensitive to the cell volume fraction. Therefore, these two dielectric parameters can be used to differentiate erythrocytes of different shapes, if dielectric spectroscopy is applied to flow-cytometric inspection of single blood cells. In addition, we revealed the applicability and limitations of the analytical theory of interfacial polarization to explain the experimental permittivities of non-spherical erythrocytes.

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

Bilayer/cytoskeleton interactions in lipid-symmetric erythrocytes assessed by a photoactivable phospholipid analogue

International Nuclear Information System (INIS)

Pradhan, D.; Schlegel, R.A.; Williamson, P.

1991-01-01

Two mechanisms have been proposed for maintenance of transbilayer phospholipid asymmetry in the erythrocyte plasma membrane, one involving specific interactions between the aminophospholipids of the inner leaflet of the bilayer and the cytoskeleton, particularly spectrin, and the other involving the aminophospholipid translocase. If the former mechanism is correct, then erythrocytes which have lost their asymmetric distribution of phospholipids should display altered bilayer/cytoskeleton interactions. To test this possibility, normal erythrocytes, erythrocytes from patients with chronic myelogenous leukemia or sickle disease, and lipid-symmetric and -asymmetric erythrocyte ghosts were labeled with the radioactive photoactivable analogue of phosphatidylethanolamine, 2-(2-azido-4-nitrobenzoyl)-1-acyl-sn-glycero-3-phospho[ 14 C] ethanolamine ([ 14 C]AzPE), previously shown to label cytoskeletal proteins from the bilayer. The labeling pattern of cytoskeletal proteins in pathologic erythrocytes and lipid-asymmetric erythrocyte ghosts was indistinguishable from normal erythrocytes, indicating that the probe detects no differences in bilayer/cytoskeleton interactions in these cells. In contrast, in lipid-symmetric erythrocyte ghosts, labeling of bands 4.1 and 4.2 and actin, and to a lesser extent ankyrin, by [ 14 C]AzPE was considerably reduced. Significantly, however, labeling of spectrin was unaltered in the lipid-symmetric cells. These results do not support a model in which spectrin is involved in the maintenance of an asymmetric distribution of phospholipids in erythrocytes

Temperature-dependent binding of cyclosporine to an erythrocyte protein

International Nuclear Information System (INIS)

Agarwal, R.P.; Threatte, G.A.; McPherson, R.A.

1987-01-01

In this competitive binding assay to measure endogenous binding capacity for cyclosporine (CsA) in erythrocyte lysates, a fixed amount of [ 3 H]CsA plus various concentrations of unlabeled CsA is incubated with aliquots of a test hemolysate. Free CsA is then adsorbed onto charcoal and removed by centrifugation; CsA complexed with a cyclosporine-binding protein (CsBP) remains in the supernate. We confirmed the validity of this charcoal-separation mode of binding analysis by comparison with equilibrium dialysis. Scatchard plot analysis of the results at 4 degrees C yielded a straight line with slope corresponding to a binding constant of 1.9 X 10(7) L/mol and a saturation capacity of approximately 4 mumol per liter of packed erythrocytes. Similar analysis of binding data at 24 degrees C and 37 degrees C showed that the binding constant decreased with increasing temperature, but the saturation capacity did not change. CsBP was not membrane bound but appeared to be freely distributed within erythrocytes. 125 I-labeled CsA did not complex with the erythrocyte CsBP. Several antibiotics and other drugs did not inhibit binding between CsA and CsBP. These findings may explain the temperature-dependent uptake of CsA by erythrocytes in whole blood and suggest that measurement of CsBP in erythrocytes or lymphocytes may help predict therapeutic response or toxicity after administration of CsA

Evaluating the genotoxic effects of workers exposed to lead using micronucleus assay, comet assay and TCR gene mutation test

International Nuclear Information System (INIS)

Chen Zhijian; Lou Jianlin; Chen Shijie; Zheng Wei; Wu Wei; Jin Lifen; Deng Hongping; He Jiliang

2006-01-01

To evaluate the genotoxic effects of lead (Pb) exposure, 25 workers in a workplace producing storage battery were monitored for three genetic end-points using micronucleus (MN) assay, comet assay and TCR gene mutation test. Twenty-five controls were matched with workers according to age, gender and smoking. The air Pb concentration in the workplace was 1.26 mg/m 3 . All subjects were measured for Pb concentration of blood by atom absorption spectrophotometry. The mean Pb concentration of blood in workers (0.32 mg/l) was significantly higher than that in controls (0.02 mg/l). The results of MN test showed that the mean micronuclei rate (MNR) and mean micronucleated cells rate (MCR) in workers were 9.04 ± 1.51 per mille and 7.76 ± 1.23 per mille , respectively, which were significantly higher than those (2.36 ± 0.42 per mille and 1.92 ± 0.31 per mille ) in controls (P -4 and 1.74 ± 0.17 x 10 -4 , respectively, there was no significant difference between workers and controls (P > 0.05). The results of our study indicated that the genetic damage was detectable in 25 workers occupationally exposed to lead

Micronucleus test for radiation biodosimetry in mass casualty events: Evaluation of visual and automated scoring

Energy Technology Data Exchange (ETDEWEB)

Bolognesi, Claudia, E-mail: claudia.bolognesi@istge.i [Environmental Carcinogenesis Unit, National Cancer Research Institute, Largo R. Benzi 10, 16132 Genoa (Italy); Balia, Cristina; Roggieri, Paola [Environmental Carcinogenesis Unit, National Cancer Research Institute, Largo R. Benzi 10, 16132 Genoa (Italy); Cardinale, Francesco [Clinical Epidemiology Unit, National Cancer Research Institute, Largo R. Benzi 10, 16132 Genoa (Italy); Department of Health Sciences, University of Genoa, Genoa (Italy); Bruzzi, Paolo [Clinical Epidemiology Unit, National Cancer Research Institute, Largo R. Benzi 10, 16132 Genoa (Italy); Sorcinelli, Francesca [Environmental Carcinogenesis Unit, National Cancer Research Institute, Largo R. Benzi 10, 16132 Genoa (Italy); Laboratory of Genetics, Histology and Molecular Biology Section, Army Medical and Veterinary, Research Center, Via Santo Stefano Rotondo 4, 00184 Roma (Italy); Lista, Florigio [Laboratory of Genetics, Histology and Molecular Biology Section, Army Medical and Veterinary, Research Center, Via Santo Stefano Rotondo 4, 00184 Roma (Italy); D' Amelio, Raffaele [Sapienza, Universita di Roma II Facolta di Medicina e Chirurgia and Ministero della Difesa, Direzione Generale Sanita Militare (Italy); Righi, Enzo [Frascati National Laboratories, National Institute of Nuclear Physics, Via Enrico Fermi 40, 00044 Frascati, Rome (Italy)

2011-02-15

In the case of a large-scale nuclear or radiological incidents a reliable estimate of dose is an essential tool for providing timely assessment of radiation exposure and for making life-saving medical decisions. Cytogenetics is considered as the 'gold standard' for biodosimetry. The dicentric analysis (DA) represents the most specific cytogenetic bioassay. The micronucleus test (MN) applied in interphase in peripheral lymphocytes is an alternative and simpler approach. A dose-effect calibration curve for the MN frequency in peripheral lymphocytes from 27 adult donors was established after in vitro irradiation at a dose range 0.15-8 Gy of {sup 137}Cs gamma rays (dose rate 6 Gy min{sup -1}). Dose prediction by visual scoring in a dose-blinded study (0.15-4.0 Gy) revealed a high level of accuracy (R = 0.89). The scoring of MN is time consuming and requires adequate skills and expertise. Automated image analysis is a feasible approach allowing to reduce the time and to increase the accuracy of the dose estimation decreasing the variability due to subjective evaluation. A good correlation (R = 0.705) between visual and automated scoring with visual correction was observed over the dose range 0-2 Gy. Almost perfect discrimination power for exposure to 1-2 Gy, and a satisfactory power for 0.6 Gy were detected. This threshold level can be considered sufficient for identification of sub lethally exposed individuals by automated CBMN assay.

Cytogenotoxicity screening of source water, wastewater and treated water of drinking water treatment plants using two in vivo test systems: Allium cepa root based and Nile tilapia erythrocyte based tests.

Science.gov (United States)

Hemachandra, Chamini K; Pathiratne, Asoka

2017-01-01

Biological effect directed in vivo tests with model organisms are useful in assessing potential health risks associated with chemical contaminations in surface waters. This study examined the applicability of two in vivo test systems viz. plant, Allium cepa root based tests and fish, Oreochromis niloticus erythrocyte based tests for screening cytogenotoxic potential of raw source water, water treatment waste (effluents) and treated water of drinking water treatment plants (DWTPs) using two DWTPs associated with a major river in Sri Lanka. Measured physico-chemical parameters of the raw water, effluents and treated water samples complied with the respective Sri Lankan standards. In the in vivo tests, raw water induced statistically significant root growth retardation, mitodepression and chromosomal abnormalities in the root meristem of the plant and micronuclei/nuclear buds evolution and genetic damage (as reflected by comet scores) in the erythrocytes of the fish compared to the aged tap water controls signifying greater genotoxicity of the source water especially in the dry period. The effluents provoked relatively high cytogenotoxic effects on both test systems but the toxicity in most cases was considerably reduced to the raw water level with the effluent dilution (1:8). In vivo tests indicated reduction of cytogenotoxic potential in the tested drinking water samples. The results support the potential applications of practically feasible in vivo biological test systems such as A. cepa root based tests and the fish erythrocyte based tests as complementary tools for screening cytogenotoxicity potential of the source water and water treatment waste reaching downstream of aquatic ecosystems and for evaluating cytogenotoxicity eliminating efficacy of the DWTPs in different seasons in view of human and ecological safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

In vitro genotoxicity of neutral red after photo-activation and metabolic activation in the Ames test, the micronucleus test and the comet assay.

Science.gov (United States)

Guérard, Melanie; Zeller, Andreas; Singer, Thomas; Gocke, Elmar

2012-07-04

Neutral red (Nr) is relatively non-toxic and is widely used as indicator dye in many biological test systems. It absorbs visible light and is known to act as a photosensitizer, involving the generation of reactive oxygen species (type-I reaction) and singlet oxygen (type-II reaction). The mutagenicity of Nr was determined in the Ames test (with Salmonella typhimurium strains TA1535, TA97, TA98, TA98NR, TA100, and TA102) with and without metabolic activation, and with and without photo-activation on agar plates. Similarly to the situation following metabolic activation, photo-mutagenicity of Nr was seen with all Salmonella strains tested, albeit with different effects between these strains. To our knowledge, Nr is the only photo-mutagen showing such a broad action. Since the effects are also observed in strains not known to be responsive to ROS, this indicates that ROS production is not the sole mode of action that leads to photo-genotoxicity. The reactive species produced by irradiation are short-lived as pre-irradiation of an Nr solution did not produce mutagenic effects when added to the bacteria. In addition, mutagenicity in TA98 following irradiation was stronger than in the nitroreductase-deficient strain TA98NR, indicating that nitro derivatives that are transformed by bacterial nitroreductase to hydroxylamines appear to play a role in the photo-mutagenicity of Nr. Photo-genotoxicity of Nr was further investigated in the comet assay and micronucleus test in L5178Y cells. Concentration-dependent increases in primary DNA damage and in the frequency of micronuclei were observed after irradiation. Copyright © 2012 Elsevier B.V. All rights reserved.

The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

Science.gov (United States)

Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

1978-11-01

An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes.

P-gp expression in brown trout erythrocytes: evidence of a detoxification mechanism in fish erythrocytes.

Science.gov (United States)

Valton, Emeline; Amblard, Christian; Wawrzyniak, Ivan; Penault-Llorca, Frederique; Bamdad, Mahchid

2013-12-05

Blood is a site of physiological transport for a great variety of molecules, including xenobiotics. Blood cells in aquatic vertebrates, such as fish, are directly exposed to aquatic pollution. P-gp are ubiquitous "membrane detoxification proteins" implicated in the cellular efflux of various xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs), which may be pollutants. The existence of this P-gp detoxification system inducible by benzo [a] pyrene (BaP), a highly cytotoxic PAH, was investigated in the nucleated erythrocytes of brown trout. Western blot analysis showed the expression of a 140-kDa P-gp in trout erythrocytes. Primary cultures of erythrocytes exposed to increasing concentrations of BaP showed no evidence of cell toxicity. Yet, in the same BaP-treated erythrocytes, P-gp expression increased significantly in a dose-dependent manner. Brown trout P-gp erythrocytes act as membrane defence mechanism against the pollutant, a property that can be exploited for future biomarker development to monitor water quality.

Effects of lead on enzymes of porphyrine biosynthesis in chloroplasts and erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Hampp, R.; Kriebitzsch, C.; Ziegler, H.

1974-01-01

Two enzymes of the chlorophyll biosynthesis pathway, delta-aminolevulinic acid dehydratase (ALAD) and prophobilinogenase (PBGA), show a pronounced sensitivity to lead ion, as was shown in isolated chloroplasts of spinach. It has been reported by several authors that the activity of ALAD involved in the hemoglobine-biosynthesis in erythrocytes is also very sensitive to lead ions. Spinach chloroplasts were isolated and sonicated and the enzyme activity tested. Calf blood was collected with heparin and kept at 0/sup 0/C until enzyme determination. Hemolyzed erythrocytes (rapid freezing and thawing twice) were used as the source of enzymes. The incubation mixture was the same as for chloroplasts; the hemoglobin content per test was about 44 mg (ALAD) and 91 mg (PBGA). ALAD in erythrocytes is somewhat more sensitive to lead ions than ALAD in chloroplasts. PBGA in erythrocytes is also inhibited by Pb/sup 2 +/ ions, again more than the chloroplast enzyme. At all concentrations of Pb/sup 2 +/ checked in our experiments the percentage of inhibition was higher with PBGA. 3 references, 1 figure.

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 �

Lack of micronucleus induction activity of ethyl tertiary-butyl ether in the bone marrow of F344 rats by sub-chronic drinking-water treatment, inhalation exposure, or acute intraperitoneal injection.

Science.gov (United States)

Noguchi, Tadashi; Kamigaito, Tomoyuki; Katagiri, Taku; Kondou, Hitomi; Yamazaki, Kazunori; Aiso, Shigetoshi; Nishizawa, Tomoshi; Nagano, Kasuke; Fukushima, Shoji

2013-01-01

Ethyl tertiary-butyl ether (ETBE) is an oxygenated gasoline additive synthesized from ethanol and isobutene that is used to reduce CO2 emissions. To support the Kyoto Protocol, the production of ETBE has undergone a marked increase. Previous reports have indicated that exposure to ETBE or methyl tertiary-butyl ether resulted in liver and kidney tumors in rats and/or mice. These reports raise concern about the effects of human exposure being brought about by the increased use of ETBE. The present study was conducted to evaluate the genotoxicity of ETBE using micronucleus induction of polychromatic erythrocytes in the bone marrow of male and female rats treated with ETBE in the drinking-water at concentrations of 0, 1,600, 4,000 or 10,000 ppm or exposed to ETBE vapor at 0, 500, 1,500 or 5,000 ppm for 13 weeks. There were no significant increases in micronucleus induction in either the drinking water-administered or inhalation-administered groups at any concentration of ETBE; although, in both groups red blood cells and hemoglobin concentration were slightly reduced in the peripheral blood in rats administered the highest concentration of ETBE. In addition, two consecutive daily intraperitoneal injections of ETBE at doses of 0, 250, 500 or 1,000 mg/kg did not increase the frequency of micronucleated bone marrow cells in either sex; all rats receiving intraperitoneal injections of ETBE at a dose of 2,000 mg/kg died after treatment day 1. These data suggest that ETBE is not genotoxic in vivo.

[Ceruloplasmin receptor on human erythrocytes].

Science.gov (United States)

Saenko, E L; Basevich, V V; Iaropolov, A I

1988-08-01

The structural fragments of the human ceruloplasmin (CP) molecule and of erythrocyte receptors which provide for the specific interaction of CP with erythrocytes were identified, and their properties were investigated. The interaction of CP with erythrocytes, both intact and treated with neuroaminidase and proteolytic enzymes (trypsin, chymotrypsin, papaine, pronase E) is described. Experiments with CP reception were performed at 4 degrees C, using [125I]CP and [125I]asialo-CP. The parameters of binding were determined in Scatchard plots. It was demonstrated that the specific binding of CP to erythrocyte receptors is determined by its interaction with two structural sites of the carbohydrate moiety of the CP molecule, i.e., the terminal residues of sialic acids and a site, (formula; see text) located at a large distance from the chain terminus.

Cytological assay of micronucleus induction by radiation in oral cancer

International Nuclear Information System (INIS)

Bhattathiri, V.N.; Bindu, L.; Remani, P.; Chandralekha, B.; Davis, C.A.; Krishnan Nair, M.

1996-01-01

A study was conducted to analyze the dose-response relationship of micronucleus (MN) induction by radiation in eighty-three patients with oral cancers. Serial scrape smears were taken before treatment and after delivery of various fractions of a course of radical radiotherapy. The smears were stained with Giemsa's stain and frequency of micronucleated cells (MNC) evaluated. Before treatment 70.5% of tumours showed MNC, the mean value being 4.18 MNC/1000 cells. The frequency of MNC, increased with increasing dose of radiation. As regards relation to treatment duration, there was initially a slight increase, followed by rapid increase and then a plateauing. Radiosensitive and resistant tumours showed differing pattern of change. The MN test by serial cytological assay has potential as a tool to understand the dynamics of radiation induced cell death and predict radiosensitivity. (author). 4 refs., 5 figs

Splenic Trapping of Heat-Treated Erythrocytes in Leukaemia and Allied Conditions

Energy Technology Data Exchange (ETDEWEB)

Badrawi, H. S.; Razzak, M. A.; Guirgis, B. [Department of Medicine and Division of Nuclear Medicine, Faculty of Medicine, Cairo University, Cairo, United Arab Republic (Egypt)

1971-02-15

In a trial to find whether or not the enlarged spleen plays a role in the production of the form of anaemia commonly encountered in leukaemias and allied conditions, 44 patients suffering from these disease states were studied using {sup 51}Cr-labelled erythrocytes heated at 50 Degree-Sign C for 60 min. Cells altered in this manner have been shown by various workers to be selectively sequestered by the spleen. As a control, the test was performed on 24 normal subjects. In these normals, the disappearance half-time of radioactivity from the circulation (T{sub Vulgar-Fraction-One-Half} amounted to 172 {+-} 69 min (mean {+-} 1 S.D.), the lowest limit being 74 min. Accordingly, patients with less than 74 min were considered to have an abnormally rapid disappearance of heat-treated erythrocytes from the circulation and consequently exaggerated splenic sequestration of these altered cells. Splenic trapping of heat-treated erythrocytes was most marked in acute leukaemia (four out of six patients). However, three had associated normoblastic hypoplasia of the sternal marrow. Corticosteroids induced a remission with reversion of both processes responsible for the anaemia in two out of the four patients. In chronic myeloid leukaemia, exaggerated splenic sequestration of altered cells was seen in four of the 15 cases examined. This condition was of extra-erythrocytic origin, since repetition of the test using normal donor heat-treated erythrocytes did not significantly alter the disappearance half-time. However, there was no correlation between the size of the spleen and its avidity for trapping the altered cells. Follow-up studies showed that therapy caused prolongation of the half-time of heat-treated erythrocytes, the effect being more apparent after corticosteroids than with X-rays or Endoxan, In Hodgkin's disease, increased red cell trapping was observed in two out of the seven patients studied. In contrast, five cases of chronic lymphatic leukaemia, six lymphosarcoma and

Role of erythrocyte tropomodulin in the biomechanics and topology of the erythrocyte membrane skeletal network

OpenAIRE

Green, Terrell Ann

2010-01-01

The erythrocyte membrane skeleton is a multi-protein complex providing mechanical properties and stability to erythrocytes. Defects in the skeleton can manifest in dysfunction and disease such as hemolytic anemia. Erythrocyte tropomodulin (E-Tmod) is a slow-growing end actin-capping protein and has been proposed that together with tropomyosin 5 or 5b they form a "molecular ruler" which dictates protofilament length of 37 nm in the network. In this study, the role for E-Tmod in the network org...

The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

Science.gov (United States)

Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

1978-01-01

An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes. Images PMID:152321

Clofazimine Induced Suicidal Death of Human Erythrocytes

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Arbace Officioso

2015-08-01

Full Text Available Background/Aims: The antimycobacterial riminophenazine clofazimine has previously been shown to up-regulate cellular phospholipase A2 and to induce apoptosis. 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. Phospholipase A2 is in part effective by fostering formation of prostaglandin E2, which triggers Ca2+ entry. Stimulators of Ca2+ entry and eryptosis further include oxidative stress and energy depletion. The present study tested, whether and how clofazimine induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, hemolysis from hemoglobin release, cytosolic Ca2+ activity ([Ca2+]i from Fluo3-fluorescence, reactive oxygen species (ROS from 2′, 7′-dichlorodihydrofluorescein diacetate (DCFDA fluorescence, and cytosolic ATP level utilizing a luciferin-luciferase assay kit. Results: A 24-48 hours exposure of human erythrocytes to clofazimine (≥1.5 µg/ml significantly increased the percentage of annexin-V-binding cells without appreciably modifying forward scatter. Clofazimine significantly increased [Ca2+]i, significantly decreased cytosolic ATP, but did not significantly modify ROS. The effect of clofazimine on annexin-V-binding was significantly blunted, but not fully abolished by removal of extracellular Ca2+, and by phospholipase A2 inhibitor quinacrine (25 µM. Clofazimine further augmented the effect of Ca2+ ionophore ionomycin (0.1 µM on eryptosis. The clofazimine induced annexin-V-binding was, however, completely abrogated by combined Ca2+ removal and addition of quinacrine. Conclusion: Clofazimine stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect in part dependent on entry of extracellular Ca2+, paralleled by cellular energy depletion and sensitive to

Extracellular histones induce erythrocyte fragility and anemia.

Science.gov (United States)

Kordbacheh, Farzaneh; O'Meara, Connor H; Coupland, Lucy A; Lelliott, Patrick M; Parish, Christopher R

2017-12-28

Extracellular histones have been shown to play an important pathogenic role in many diseases, primarily through their cytotoxicity toward nucleated cells and their ability to promote platelet activation with resultant thrombosis and thrombocytopenia. In contrast, little is known about the effect of extracellular histones on erythrocyte function. We demonstrate in this study that histones promote erythrocyte aggregation, sedimentation, and using a novel in vitro shear stress model, we show that histones induce erythrocyte fragility and lysis in a concentration-dependent manner. Furthermore, histones impair erythrocyte deformability based on reduced passage of erythrocytes through an artificial spleen. These in vitro results were mirrored in vivo with the injection of histones inducing anemia within minutes of administration, with a concomitant increase in splenic hemoglobin content. Thrombocytopenia and leukopenia were also observed. These findings suggest that histones binding to erythrocytes may contribute to the elevated erythrocyte sedimentation rates observed in inflammatory conditions. Furthermore, histone-induced increases in red blood cell lysis and splenic clearance may be a significant factor in the unexplained anemias seen in critically ill patients. © 2017 by The American Society of Hematology.

The mechanism of erythrocyte sedimentation. Part 2: The global collapse of settling erythrocyte network.

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Pribush, A; Meyerstein, D; Meyerstein, N

2010-01-01

Results reported in the companion paper showed that erythrocytes in quiescent blood are combined into a network followed by the formation of plasma channels within it. This study is focused on structural changes in the settling dispersed phase subsequent to the channeling and the effect of the structural organization on the sedimentation rate. It is suggested that the initial, slow stage of erythrocyte sedimentation is mainly controlled by the gravitational compactness of the collapsed network. The lifetime of RBC network and hence the duration of the slow regime of erythrocyte sedimentation decrease with an increase in the intercellular pair potential and with a decrease in Hct. The gravitational compactness of the collapsed network causes its rupture into individual fragments. The catastrophic collapse of the network transforms erythrocyte sedimentation from slow to fast regime. The size of RBC network fragment is insignificantly affected by Hct and is mainly determined by the intensity of intercellular attractive interactions. When cells were suspended in the weak aggregating medium, the Stokes radius of fragments does not differ measurably from that of individual RBCs. The proposed mechanism provides a reasonable explanation of the effects of RBC aggregation, Hct and the initial height of the blood column on the delayed erythrocyte sedimentation.

Erythrocyte fluorescence and lead intoxication.

Science.gov (United States)

Clark, K G

1976-01-01

Blood samples from people exposed to inorganic lead were examined by fluorescence microscopy for excess erythrocyte porphyrin. With continued lead absorption, fluorescent erythrocytes appeared in the circulation of workers handling this metal or its compounds, and they progressively increased in number and brilliance. These changes ensued if the blood lead concentration was maintained above 2-42 mumol/l (50 mug/100 ml), and preceded any material fall in the haemoglobin value. At one factory, 62-5% of 81 symptomless workers showed erythrocyte fluorescence attributable to the toxic effects of lead. Excess fluorocytes were found in blood samples from a child with pica and three of her eight siblings. These four were subsequently shown to have slightly increased blood lead concentrations (2-03 to 2-32 mumol/l). Fluorescence microscopy for excess erythrocyte porphyrin is a sensitive method for the detection of chronic lead intoxication. A relatively slight increase in the blood lead is associated with demonstrabel changes in erythrocyte porphyrin content. The procedure requires little blood, and may be performed upon stored samples collected for lead estimation. The results are not readily influenced by contamination, and provide good confirmatory evidence for the absorption of biochemically active lead. PMID:963005

Low dose effects detected by micronucleus assay in lymphocytes

International Nuclear Information System (INIS)

Koeteles, G.J.; Bojtor, I.; Kubasova, T.; Horvath, G.

1997-01-01

The effects of low doses of X-rays between 0.01 and 1 Gy were studied on whole blood samples of various individuals using the cytokinesis-blocked lymphocyte micronucleus assay as an endpoint. The adaptive response could be induced in G 0 cells by 0.01 Gy followed by 1 Gy challenging dose within a time period of 8 hours, in vitro. The probability distribution of micronucleus increments in those samples which had received very low doses in the range 0.01-0.05 Gy proved to be of asymmetrical type (i.e. lognormal) -very likely to the same shape which has been verified for unirradiated (control) population - while the variable turned to be normally distributed at or above 1 Gy. Profound changes have been experienced in the main characteristics of the linear dose - response relationship and in regression parameters, as well, when successively lessened dose ranges were studied toward 0.01 Gy. In the range below ∼ 0.2 Gy the response were found to be unrelated to the absorbed dose. These findings suggest that in (very) low dose range a higher attention should be needed to biological parameters like repair, protective mechanisms and antioxidant capacities, rather than to the absorbed radiation energy only. (author)

Changes in haematology, plasma biochemistry and erythrocyte ...

African Journals Online (AJOL)

The results suggest that maintaining wild birds in captivity for a prolonged period could be stressful as shown by the heterophil/lymphocytes ratio and reduced erythrocyte osmotic resistance, and could lead to decreases in erythrocyte parameters and muscle wasting. Keywords: Haematological parameters, erythrocyte ...

Triggering of Erythrocyte Cell Membrane Scrambling by Emodin

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Morena Mischitelli

2016-11-01

Full Text Available Background/Aims: The natural anthraquinone derivative emodin (1,3,8-trihydroxy-6-methylanthraquinone is a component of several Chinese medicinal herbal preparations utilized for more than 2000 years. The substance has been used against diverse disorders including malignancy, inflammation and microbial infection. The substance is effective in part by triggering suicidal death or apoptosis. Similar to apoptosis of nucleated cells erythrocytes may enter suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signaling involved in the triggering of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i, oxidative stress and ceramide. The present study aimed to test, whether emodin induces eryptosis and, if so, to elucidate underlying cellular mechanisms. Methods: Phosphatidylserine abundance at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence, and ceramide abundance utilizing specific antibodies. Results: Exposure of human erythrocytes for 48 hours to emodin (≥ 10 µM significantly increased the percentage of annexin-V-binding cells, and at higher concentrations (≥ 50 µM significantly increased forward scatter. Emodin significantly increased Fluo3-fluorescence (≥ 10 µM, DCFDA fluorescence (75 µM and ceramide abundance (75 µM. The effect of emodin on annexin-V-binding was significantly blunted but not abolished by removal of extracellular Ca2+. Conclusions: Emodin triggers phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part due to stimulation of Ca2+ entry and paralleled by oxidative stress and ceramide appearance at the erythroctye surface.

Micronucleus formation in cultured human keratinocytes following exposure to mitomycin C and cyclophosphamide.

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van Pelt, F N; Haring, R M; Overkamp, M J; Weterings, P J

1991-02-01

A method is described to investigate the induction of micronuclei in cultured human keratinocytes after short-term exposure to known clastogenic agents. The cytokinesis-block method was applied to facilitate the scoring of micronucleated cells. Mitomycin C, a direct-acting compound, caused a 5-20-fold increase in micronuclei over the controls at the highest concentration tested (1 microgram/ml). Cyclophosphamide, an agent requiring metabolic activation, did not induce the formation of micronuclei in cultured keratinocytes. However, after pretreatment of the keratinocyte cultures with Aroclor 1254 for 72 h, exposure to cyclophosphamide resulted in a 3-fold increase in micronucleus frequency over the controls. No cytogenetic effect of Aroclor 1254 was observed in control experiments.

Conjugated Bilirubin Triggers Anemia by Inducing Erythrocyte Death

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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

In vitro and in vivo antimutagenic effects of DIG, a herbal preparation of Berberis vulgaris, Taraxacum officinale and Arctium lappa, against mitomycin C.

Science.gov (United States)

Di Giorgio, C; Boyer, L; De Meo, M; Laurant, C; Elias, R; Ollivier, E

2015-07-01

DIG, a liquid herbal preparation made from a mixture of diluted mother tinctures of Berberis vulgaris, Taraxacum officinale and Arctium lappa, was assessed for its antimutagenic properties against mitomycin C. The micronucleus assay on Chinese hamster ovary (CHO)-K1 cells was used to evaluate the in vitro anticlastogenic activity of DIG compared to those of separately diluted mother tinctures. The micronucleus assay was performed on mouse erythrocytes and the comet assay was performed on mouse liver, kidney, lung, brain and testicles to assess the protective effects of DIG (0.2 and 2 % at libitum) against an intraperitoneal injection of mitomycin C (1 mg Kg(-1)) in mice. DIG exerted a powerful anticlastogenic activity, under both pretreatment and simultaneous treatment conditions as assessed by the micronucleus assay in CHO-K1 cells. Its protective activity was greater than that observed for each mother tincture. DIG reduced micronuclei levels in mouse erythrocytes and suppressed >80 % of DNA strand breaks in the liver, kidney, lung, brain and testicles of mice exposed to mitomycin C.

Sickle erythrocytes inhibit human endothelial cell DNA synthesis

International Nuclear Information System (INIS)

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

1990-01-01

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

Allosensibilisation to erythrocyte antigens (literature review

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N. V. Mineeva

2015-01-01

Full Text Available In this article literature review of the causes of allosensibilisation to erythrocyte antigens are presented. It is shown that the ability to produce antierythrocyte antibodies is affected by many factors, principal of whom it is difficult to identify. For the allosensibilisation development requires genetically determined differences in erythrocyte antigens phenotypes of donor and recipient, mother and fetus, which can lead to immune response and antibodies production. The biochemical nature of erythrocyte antigens, antigen dose (the amount of transfused doses, the number of antigens determinants on donor and fetus erythrocytes, the number of pregnancies are important. Individual patient characteristics: age, gender, diseases, the use of immunosuppressive therapy and the presence of inflammatory processes, are also relevant. Note that antibody to one erythrocyte antigens have clinical value, and to the other – have no. The actual data about frequency of clinically significant antibodies contribute to the development of post-transfusion hemolytic complications prophylaxis as well as the improvement of laboratory diagnosis of hemolytic disease of the newborn in the presence of maternal antierythrocyte antibodies.

Significance of the proportion of binucleate cells in the micronucleus assay

International Nuclear Information System (INIS)

Imamura, Masahiro; Edgren, M.R.

1994-01-01

Using treatment with cytochalasin-B (Cyt-B) for the induction of a cytokinetic block, the significance of the proportion of binucleate cells (BNC) in the micronucleus (MN) assay was investigated in a methodological study. A Chinese hamster cell line V79 was used in which MN were induced by radiation. In complementary tests the radiation effect in inducing MN was enhanced by depletion of the cellular glutathione content with buthionine sulfoximine (BSO). The data indicated that the concentration of Cyt-B is the major factor which determines the proportion of BNC. This proportion was shown to be independent of radiation dose and of BSO. Furthermore, the MN frequency was not related to the percentage of BNC. Therefore, a high proportion of BNC may be practical for the MN assay, but may not make the technique more accurate. (author)

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...

Assessment of the mutagenic and antimutagenic activity of Synadenium umbellatum Pax latex by micronucleus test in mice

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PR. Melo-Reis

Full Text Available Synadenium umbellatum Pax, popularly known as "cola-nota", is a medicinal plant that grows in tropical regions. The latex of this plant is used against various diseases, such as diabetes mellitus, leprosy, tripanosomiasis, leukemia, and several malignant tumors. The mutagenic, antimutagenic, and cytotoxic effects of the latex of this plant were investigated by measuring the frequency of micronuclei in mice bone marrow cells. To evaluate mutagenicity, the animals were treated with four doses of latex (10, 30, 50, and 100 mg/kg body weight. To study the antimutagenic activity, the animals were simultaneously treated with latex and mitomycin C (4 mg/kg. The cytotoxicity was evaluated by polychromatic and normochromatic erythrocytes ratio. Our results showed a significant increase of frequency of micronucleated polychromatic erythrocytes (MNPCE compared to the negative control group (p 0.05 was detected at the doses of 50 and 100 mg/kg. Under our experimental conditions, the results obtained indicate strong mutagenic and cytotoxic activity of S. umbellatum latex except the dose of 10 mg/kg and moderate antimutagenic effect at lower doses.

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.

Study on ionizing radiation to the workers' lymphocyte micronucleus rate and chromosome aberrations

International Nuclear Information System (INIS)

Li Jianhua; Wang Linchao; He Wei

2007-01-01

Objective: To study lymphocyte genetic material of an iron and steel enterprise workers exposed to the ionizing radiation, find out measures to protect their health and reduce ionizing radiation occupation harm. Methods: 342 workers were choseh as the exposed group who worked in an iron and steel enterprise in the beam installment operation, to examine their circumference blood lymphocyte micronucleus rate and the chromosome aberrations, simultaneously select 280 chefs as the control group, The irradiation dosage was determined and statistical analysis was carded out wich the consideration of their length of work and differences in work post. Results: Exposed group: the micronucleus rate masculine gender (MNR), 4 people, the masculine gender pick out rate is 12.87%. The chromosome aberration factor masculine gender (CAF), 12 people, the masculine rate is 3.51%. Control group: MNR 3 people, the asculine gender pick out rate is 1.07%; CAF 2 people, masculine gender rate is 0.72%. Comparing the two groups, every item has the significant difference. Workers in is the exposed group workers have the average exposure dose of 6.73mSv/a, MNR,CAF are illuminated to the dosage have a positive line correlation. They become increased as the job lenght prolongs. The nucleon name, the material calculation and the medical X-radial are responsible for the highest ratio. Conclusion: In iron and steel enterprises, long-time ionizing radiation can cause the workers' circumference blood lymphocyte micronucleus rate and the chromosome aberrations obvious to rise. The beam protection measures strengthened so as to reduce the harms to workers. (authors)

The Uremic Toxin Acrolein Promotes Suicidal Erythrocyte Death

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Mohamed Siyabeldin E. Ahmed

2013-05-01

Full Text Available Background: Anemia is a major complication of end stage renal disease. The anemia is mainly the result of impaired formation of erythrocytes due to lack of erythropoietin and iron deficiency. Compelling evidence, however, points to the contribution of accelerated erythrocyte death, which decreases the life span of circulating erythrocytes. Erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and by cell membrane scrambling with phosphatidylserine-exposure at the erythrocyte surface. Triggers of eryptosis include increase of cytosolic Ca2+-activity ([Ca2+]i. Erythrocytes could be sensitized to cytosolic Ca2+ by ceramide. In end stage renal disease, eryptosis may possibly be stimulated by uremic toxins. The present study explored, whether the uremic toxin acrolein could trigger eryptosis. Methods: Cell volume was estimated from forward scatter, phosphatidylserine-exposure from annexin-V-binding, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and ceramide from fluorescent antibodies. Results: A 48 h exposure to acrolein (30 － 50 µM did not significantly modify [Ca2+]i but significantly decreased forward scatter and increased annexin-V-binding. Acrolein further triggered slight, but significant hemolysis and increased ceramide formation in erythrocytes. Acrolein (50 µM induced annexin-V-binding was significantly blunted in the nominal absence of extracellular Ca2+. Acrolein augmented the annexin-V-binding following treatment with Ca2+ ionophore ionomycin (1 µM. Conclusion: Acrolein stimulates suicidal erythrocyte death or eryptosis, an effect at least in part due to stimulation of ceramide formation with subsequent sensitisation of the erythrocytes to cytosolic Ca2+.

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

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

The malaria parasite RhopH protein complex interacts with erythrocyte calmyrin identified from a comprehensive erythrocyte protein library.

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Miura, Toyokazu; Takeo, Satoru; Ntege, Edward H; Otsuki, Hitoshi; Sawasaki, Tatsuya; Ishino, Tomoko; Takashima, Eizo; Tsuboi, Takafumi

2018-06-02

Malaria merozoite apical organelles; microneme and rhoptry secreted proteins play functional roles during and following invasion of host erythrocytes. Among numerous proteins, the rhoptries discharge high molecular weight proteins known as RhopH complex. Recent reports suggest that the RhopH complex is essential for growth and survival of the malaria parasite within erythrocytes. However, an in-depth understanding of the host-parasite molecular interactions is indispensable. Here we utilized a comprehensive mouse erythrocyte protein library consisting of 443 proteins produced by a wheat germ cell-free system, combined with AlphaScreen technology to identify mouse erythrocyte calmyrin as an interacting molecule of the rodent malaria parasite Plasmodium yoelii RhopH complex (PyRhopH). The PyRhopH interaction was dependent on the calmyrin N-terminus and divalent cation capacity. The finding unveils a recommendable and invaluable usefulness of our comprehensive mouse erythrocyte protein library together with the AlphaScreen technology in investigating a wide-range of host-parasite molecular interactions. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of dietary fat on lipid composition of serum and erythrocytes of the swine and in vitro incorporation of fatty acids into erythrocyte membranes

International Nuclear Information System (INIS)

Sato, Hiroaki

1974-01-01

Changes in ftty acid patterns of lipids in serum and erythrocytes induced by dietary fats and in vitro incorporation of fatty acids into erythrocyte membranes were investigated with pigs. On feeding various diets, it was found that fatty acid composition of serum and erythrocytes could be modified and altered toward the fatty acid pattern of the diet. In vitro, the incorporation of labelled fatty acids into erythrocyte membranes was accelerated by the addition of cofactors such as lysolecithin, CoA and ATP. Dietary fats also had certain effects on the incorporation of fatty acids into erythrocyte membranes. Erythrocytes, collected from the blood of pigs fed corn oil, incorporated and also released more labelled linoleate than those of pigs fed hydrogenated soybean oil. Palmitic acid was more slowly incorporated into erythrocyte membranes than linoleic acid in the pigs fed both a commercial chow and scheduled meals, indicating selective esterification of fatty acids in the erythrocyte membranes. (author)

Delivery route determines the presence of immune complexes on umbilical cord erythrocytes.

Science.gov (United States)

de Lima, Andrés; Franco, Luis C; Sarmiento, Andrés; González, John M

2017-11-01

Umbilical cord blood offers a unique opportunity to study the basal level of immunoglobulin complexes. This study aims to determine the presence of immune complexes and complement deposition on erythrocytes from umbilical cord blood from normal, full-term pregnancies. In vitro pre-formed IgA, IgG, and IgM complexes were used as positive control for flow cytometry detection, and for C3d deposition. Blood samples (34) of umbilical cord blood taken from vaginal and cesarean deliveries were tested for the presence of immunoglobulin complexes. Fourteen samples from vaginal deliveries and 20 samples from cesarean deliveries were assessed. IgG and IgM complexes were detected on erythrocytes, whereas no IgA complexes or complement deposition was observed. Interestingly, the percentage of IgG complexes was higher on erythrocytes from vaginal delivery samples compared to those from cesarean deliveries. No other associations between immune complexes and other maternal or newborn variables were found. IgG and IgM complexes seem to be normally present on umbilical cord erythrocytes. Erythrocytes from vaginal deliveries have a higher percentage of IgG complexes present compared to that from cesarean deliveries. Since no C3d activity was detected, these complexes are non-pathological and should be part of the newborn's initial innate immune response.

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...

Structure of malaria invasion protein RH5 with erythrocyte basigin and blocking antibodies.

Science.gov (United States)

Wright, Katherine E; Hjerrild, Kathryn A; Bartlett, Jonathan; Douglas, Alexander D; Jin, Jing; Brown, Rebecca E; Illingworth, Joseph J; Ashfield, Rebecca; Clemmensen, Stine B; de Jongh, Willem A; Draper, Simon J; Higgins, Matthew K

2014-11-20

Invasion of host erythrocytes is essential to the life cycle of Plasmodium parasites and development of the pathology of malaria. The stages of erythrocyte invasion, including initial contact, apical reorientation, junction formation, and active invagination, are directed by coordinated release of specialized apical organelles and their parasite protein contents. Among these proteins, and central to invasion by all species, are two parasite protein families, the reticulocyte-binding protein homologue (RH) and erythrocyte-binding like proteins, which mediate host-parasite interactions. RH5 from Plasmodium falciparum (PfRH5) is the only member of either family demonstrated to be necessary for erythrocyte invasion in all tested strains, through its interaction with the erythrocyte surface protein basigin (also known as CD147 and EMMPRIN). Antibodies targeting PfRH5 or basigin efficiently block parasite invasion in vitro, making PfRH5 an excellent vaccine candidate. Here we present crystal structures of PfRH5 in complex with basigin and two distinct inhibitory antibodies. PfRH5 adopts a novel fold in which two three-helical bundles come together in a kite-like architecture, presenting binding sites for basigin and inhibitory antibodies at one tip. This provides the first structural insight into erythrocyte binding by the Plasmodium RH protein family and identifies novel inhibitory epitopes to guide design of a new generation of vaccines against the blood-stage parasite.

In vitro and ex vivo effect of hyaluronic acid on erythrocyte flow properties

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Palatnik S

2010-02-01

Full Text Available Abstract Background Hyaluronic acid (HA is present in many tissues; its presence in serum may be related to certain inflammatory conditions, tissue damage, sepsis, liver malfunction and some malignancies. In the present work, our goal was to investigate the significance of hyaluronic acid effect on erythrocyte flow properties. Therefore we performed in vitro experiments incubating red blood cells (RBCs with several HA concentrations. Afterwards, in order to corroborate the pathophysiological significance of the results obtained, we replicated the in vitro experiment with ex vivo RBCs from diagnosed rheumatoid arthritis (RA patients, a serum HA-increasing pathology. Methods Erythrocyte deformability (by filtration through nucleopore membranes and erythrocyte aggregability (EA were tested on blood from healthy donors additioned with purified HA. EA was measured by transmitted light and analyzed with a mathematical model yielding two parameters, the aggregation rate and the size of the aggregates. Conformational changes of cytoskeleton proteins were estimated by electron paramagnetic resonance spectroscopy (EPR. Results In vitro, erythrocytes treated with HA showed increased rigidity index (RI and reduced aggregability, situation strongly related to the rigidization of the membrane cytoskeleton triggered by HA, as shown by EPR results. Also, a significant correlation (r: 0.77, p Conclusions Our results lead us to postulate the hypothesis that HA interacts with the erythrocyte surface leading to modifications in erythrocyte rheological and flow properties, both ex vivo and in vitro.

Reduced Plasmodium vivax erythrocyte infection in PNG Duffy-negative heterozygotes.

Science.gov (United States)

Kasehagen, Laurin J; Mueller, Ivo; Kiniboro, Benson; Bockarie, Moses J; Reeder, John C; Kazura, James W; Kastens, Will; McNamara, David T; King, Charles H; Whalen, Christopher C; Zimmerman, Peter A

2007-03-28

Erythrocyte Duffy blood group negativity reaches fixation in African populations where Plasmodium vivax (Pv) is uncommon. While it is known that Duffy-negative individuals are highly resistant to Pv erythrocyte infection, little is known regarding Pv susceptibility among heterozygous carriers of a Duffy-negative allele (+/-). Our limited knowledge of the selective advantages or disadvantages associated with this genotype constrains our understanding of the effect that interventions against Pv may have on the health of people living in malaria-endemic regions. We conducted cross-sectional malaria prevalence surveys in Papua New Guinea (PNG), where we have previously identified a new Duffy-negative allele among individuals living in a region endemic for all four human malaria parasite species. We evaluated infection status by conventional blood smear light microscopy and semi-quantitative PCR-based strategies. Analysis of a longitudinal cohort constructed from our surveys showed that Duffy heterozygous (+/-) individuals were protected from Pv erythrocyte infection compared to those homozygous for wild-type alleles (+/+) (log-rank tests: LM, p = 0.049; PCR, p = 0.065). Evaluation of Pv parasitemia, determined by semi-quantitative PCR-based methods, was significantly lower in Duffy +/- vs. +/+ individuals (Mann-Whitney U: p = 0.023). Overall, we observed no association between susceptibility to P. falciparum erythrocyte infection and Duffy genotype. Our findings provide the first evidence that Duffy-negative heterozygosity reduces erythrocyte susceptibility to Pv infection. As this reduction was not associated with greater susceptibility to Pf malaria, our in vivo observations provide evidence that Pv-targeted control measures can be developed safely.

Exhaustive Exercise-induced Oxidative Stress Alteration of Erythrocyte Oxygen Release Capacity.

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Xiong, Yanlian; Xiong, Yanlei; Wang, Yueming; Zhao, Yajin; Li, Yaojin; Ren, Yang; Wang, Ruofeng; Zhao, Mingzi; Hao, Yitong; Liu, Haibei; Wang, Xiang

2018-05-24

The aim of the present study is to explore the effect of exhaustive running exercise (ERE) in the oxygen release capacity of rat erythrocytes. Rats were divided into sedentary control (C), moderate running exercise (MRE) and exhaustive running exercise groups. The thermodynamics and kinetics properties of the erythrocyte oxygen release process of different groups were tested. We also determined the degree of band-3 oxidative and phosphorylation, anion transport activity and carbonic anhydrase isoform II(CAII) activity. Biochemical studies suggested that exhaustive running significantly increased oxidative injury parameters in TBARS and methaemoglobin levels. Furthermore, exhaustive running significantly decreased anion transport activity and carbonic anhydrase isoform II(CAII) activity. Thermodynamic analysis indicated that erythrocytes oxygen release ability also significantly increased due to elevated 2,3-DPG level after exhaustive running. Kinetic analysis indicated that exhaustive running resulted in significantly decreased T50 value. We presented evidence that exhaustive running remarkably impacted thermodynamics and kinetics properties of RBCs oxygen release. In addition, changes in 2,3-DPG levels and band-3 oxidation and phosphorylation could be the driving force for exhaustive running induced alterations in erythrocytes oxygen release thermodynamics and kinetics properties.

Label-free sensor for automatic identification of erythrocytes using digital in-line holographic microscopy and machine learning.

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

2018-04-30

Cell types of erythrocytes should be identified because they are closely related to their functionality and viability. Conventional methods for classifying erythrocytes are time consuming and labor intensive. Therefore, an automatic and accurate erythrocyte classification system is indispensable in healthcare and biomedical fields. In this study, we proposed a new label-free sensor for automatic identification of erythrocyte cell types using a digital in-line holographic microscopy (DIHM) combined with machine learning algorithms. A total of 12 features, including information on intensity distributions, morphological descriptors, and optical focusing characteristics, is quantitatively obtained from numerically reconstructed holographic images. All individual features for discocytes, echinocytes, and spherocytes are statistically different. To improve the performance of cell type identification, we adopted several machine learning algorithms, such as decision tree model, support vector machine, linear discriminant classification, and k-nearest neighbor classification. With the aid of these machine learning algorithms, the extracted features are effectively utilized to distinguish erythrocytes. Among the four tested algorithms, the decision tree model exhibits the best identification performance for the training sets (n = 440, 98.18%) and test sets (n = 190, 97.37%). This proposed methodology, which smartly combined DIHM and machine learning, would be helpful for sensing abnormal erythrocytes and computer-aided diagnosis of hematological diseases in clinic. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of gamma radiation on levels of adenine nucleotides in erythrocytes of healthy individuals after submaximum physical exertion

International Nuclear Information System (INIS)

Zagorski, T.; Dudek, I.; Mazurek, M.; Berkan, L.; Chmielewski, H.; Kedziora, J.

1994-01-01

The authors studied the effect of gamma radiation and submaximum physical exercise on adenosine-5'-triphosphate (ATP), adenosine-5'-diphosphate (ADP) and adenosine-5'-monophosphate (AMP) contents in erythrocytes of healthy males. Twenty one men aged 20-22 years were examined. They underwent physical exercise at doses of 2 w/kg body weight for 15 min. Erythrocytes were exposed to gamma radiation (500 Gy doses) from 60 Co source. The concentration of adenine nucleotides in erythrocytes was measured by the Boehringer Mannheim tests. The submaximum physical exercise was found to decrease ATP content and to increase ADP and AMP in erythrocytes. Gamma radiation at 500 Gy dose was found to decrease ATP concentration in erythrocytes both at rest and after submaximum exercise and to increase AD content. It was revealed that AMP content increased at rest and decreased after submaximum exercise in irradiated erythrocytes. (author). 20 refs, 1 tab

Micronucleus assay for radiation workers

International Nuclear Information System (INIS)

Balasem, A.N.; Ali, A.S.K.

1997-01-01

Micronucleus assay was performed on 49 radiation workers and 22 healthy volunteers. Radiation workers were subdivided into two groups according to their employments durations in the radiation field. Group a consisted of 18 radiation workers who have been in this work between 5 and 22 years. Group b included 31 employees who have been classified as radiation workers for 1 to 4.5 years. Statistical analysis showed significant variations between the yields of micronuclei in groups A and B as well as between group A and a group of healthy controls. Meanwhile no significant difference was noticed between the yields of micronuclei in group B and the corresponding values in the healthy controls. The possible effect of age in the induction of micronuclei was discussed and a comparison with the yield of chromosomal aberrations was described. It seems that cytokinesis- blocking method may be used to detect the radiation-induced micronuclei in workers exposed occupationally to ionizing radiation in levels below the maximum permissible limit of 0.05 Sv per year

Correlation of In Vivo Versus In Vitro Benchmark Doses (BMDs) Derived From Micronucleus Test Data: A Proof of Concept Study.

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Soeteman-Hernández, Lya G; Fellows, Mick D; Johnson, George E; Slob, Wout

2015-12-01

In this study, we explored the applicability of using in vitro micronucleus (MN) data from human lymphoblastoid TK6 cells to derive in vivo genotoxicity potency information. Nineteen chemicals covering a broad spectrum of genotoxic modes of action were tested in an in vitro MN test using TK6 cells using the same study protocol. Several of these chemicals were considered to need metabolic activation, and these were administered in the presence of S9. The Benchmark dose (BMD) approach was applied using the dose-response modeling program PROAST to estimate the genotoxic potency from the in vitro data. The resulting in vitro BMDs were compared with previously derived BMDs from in vivo MN and carcinogenicity studies. A proportional correlation was observed between the BMDs from the in vitro MN and the BMDs from the in vivo MN assays. Further, a clear correlation was found between the BMDs from in vitro MN and the associated BMDs for malignant tumors. Although these results are based on only 19 compounds, they show that genotoxicity potencies estimated from in vitro tests may result in useful information regarding in vivo genotoxic potency, as well as expected cancer potency. Extension of the number of compounds and further investigation of metabolic activation (S9) and of other toxicokinetic factors would be needed to validate our initial conclusions. However, this initial work suggests that this approach could be used for in vitro to in vivo extrapolations which would support the reduction of animals used in research (3Rs: replacement, reduction, and refinement). © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology.

Therapeutic efficacy and safety evaluation of erythrocyte concentrate used in dogs

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Ildiko Barabasi

2016-11-01

Full Text Available Therapeutic efficacy and safety evaluation of erythrocyte concentrate used in dogs 1Ildikó BARABÁSI, 1Cristina ȘTEFǍNUȚ, 1Laurenţ OGNEAN 1University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400037, Manastur street, no.3-5, Cluj-Napoca, Romania *Corresponding author: lognean@yahoo.com   Keywords: dogs, erythrocyte concentrate, hematocrit, immune-mediated hemolytic anemia, transfusion therapy Introduction: The minimum dose of whole blood products as well as erythrocyte concentrate has been under a lot of debate, new equations for calculating the optimal dose being made up from a large variety of hematologists (Kisielewicz et al 2014; Helm and Knottenbelt, 2010; Gibson, 2007. Aim: The therapeutical efficacy of erythrocyte concentrates in dogs with different types of anemia by measuring the hematocrit level 6 hours after the transfusion and a complete blood count 5 days post-transfusion therapy. Materials and methods: Blood tests were performed with ADIVA hematological analyzer; the 6 hour post-transfusion hematocrit was determined by a micro hematocrit. On admission every patient received a routine blood test that included 40 hematological parameters and 21 biochemical parameters. In addition, a detailed examination of the blood smears was also performed by the ADIVA hematological analyzer with 26 parameters that mostly referred to red blood cell and white blood cell morphology. Blood typing was done using the RapidVet quick test kit. Patients received only type specific blood and to limit transfusion reaction occurrences, in addition, a crossmatch test was performed before every transfusion. Statistical analysis was accomplished with GraphPadInStat 3.0 and the graphical depiction of the obtained results was made using the Origin 8.5. graphics program. Results: Statistical analysis reveal that the total red blood cell count underwent very significant changes (p=0.0052 as well as the hemoglobin (p=0.0085. The hematocrit

Micronucleus as biomarkers of cancer risk in anabolic androgenic steroids users.

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Souza, L da Cunha Menezes; da Cruz, L A; Cerqueira, E de Moraes Marcílio; Meireles, Jrc

2017-03-01

The use of anabolic androgenic steroids (AAS) has grown among practitioners of recreational bodybuilding, with significant contributions of designer steroids, aiming muscle hypertrophy in healthy subjects. The abusive use of AAS in general is associated with adverse effects; one of the most worrisome is cancer development. The aim of this study was to evaluate the effectiveness of the cytokinesis block micronucleus (CBMN) test in human lymphocytes in identifying risk groups for cancer development in users of AAS. Blood was collected from 15 AAS users bodybuilders (G1), 20 non-users bodybuilders (G2) and 20 non-users sedentary (G3). MN analysis was performed on a minimum of 1000 binucleated lymphocytes. The occurrence of MN was significantly higher ( p < 0.05) in individuals of G1 compared to G2 and G3. The results indicate the sensitivity of CBMN in human lymphocytes in the identification of chromosomal damage in consequence of AAS.

Cytokinesis-block micronucleus assay evolves into a 'cytome' assay of chromosomal instability, mitotic dysfunction and cell death

International Nuclear Information System (INIS)

Fenech, Michael

2006-01-01

The cytokinesis-block micronucleus (CBMN) assay was originally developed as an ideal system for measuring micronuclei (MNi) however it can also be used to measure nucleoplasmic bridges (NPBs), nuclear buds (NBUDs), cell death (necrosis or apoptosis) and nuclear division rate. Current evidence suggests that (a) NPBs originate from dicentric chromosomes in which the centromeres have been pulled to the opposite poles of the cell at anaphase and are therefore indicative of DNA mis-repair, chromosome rearrangement or telomere end-fusions, (b) NPBs may break to form MNi, (c) the nuclear budding process is the mechanism by which cells remove amplified and/or excess DNA and is therefore a marker of gene amplification and/or altered gene dosage, (d) cell cycle checkpoint defects result in micronucleus formation and (e) hypomethylation of DNA, induced nutritionally or by inhibition of DNA methyl transferase can lead to micronucleus formation either via chromosome loss or chromosome breakage. The strong correlation between micronucleus formation, nuclear budding and NPBs (r = 0.75-0.77, P < 0.001) induced by either folic acid deficiency or exposure to ionising radiation is supportive of the hypothesis that folic acid deficiency and/or ionising radiation cause genomic instability and gene amplification by the initiation of breakage-fusion-bridge cycles. In its comprehensive mode, the CBMN assay measures all cells including necrotic and apoptotic cells as well as number of nuclei per cell to provide a measure of cytotoxicity and mitotic activity. The CBMN assay has in fact evolved into a 'cytome' method for measuring comprehensively chromosomal instability phenotype and altered cellular viability caused by genetic defects and/or nutrional deficiencies and/or exogenous genotoxins thus opening up an exciting future for the use of this methodology in the emerging fields of nutrigenomics and toxicogenomics and their combinations

An improved in vitro micronucleus assay to biological dosimetry

International Nuclear Information System (INIS)

Ocampo, Ivette Z.; Okazaki, Kayo; Vieira, Daniel P.

2013-01-01

The biological dosimetry is widely used to estimate the absorbed dose in people occupationally or accidentally exposed to the radiation for a better medical treatment, minimizing the harmful effects. Many techniques and methods have been proposed to detect and quantify the radioinduced lesions in genetic material, among them, the micronucleus (MN) assay. In the present study, we proposed an improved in vitro micronucleus technique that is rapid, sensitive and with minor cell manipulations. Assays were carried out with human tumor cells (MCF-7) seeded (3x10 4 cells) in slides placed into Petri dishes. Adherent cells were maintained with RPMI medium, supplemented with fetal calf serum, 1 % antibiotics, cytochalasin B (2 μg/mL), and incubated at 37 deg C in the presence of 5% CO2 for 72h. Cells were pre-treated for 24h with aminoguanidine, a nitric oxide synthase inhibitor. Nitric oxide is an intracellular free-radical, involved in DNA double-strand break repair mechanisms. After incubation, adherent cells on slides were briefly fixed with paraformaldehyde and stained with acridine orange (100 μg/mL) for analysis through fluorescence microscopy. Dye fluorescence permitted accurate discrimination between nuclei and micronuclei (bright green) and cytoplasm (red), and made possible a faster counting of binucleated cells. Aminoguanidine (2 mM) induced significant increase (p< 0.05) in frequencies of binucleated cells with micronuclei and in the number of micronuclei per binucleated cell. Data showed that proposed modifications permit to understand an early aspect of NO inhibition and suggested an improved protocol to MN assays. (author)

Comet assay and micronucleus tests on Oreochromis niloticus (Perciforme: Cichlidae) exposed to raw sugarcane vinasse and to phisicochemical treated vinasse by pH adjustment with lime (CaO).

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Correia, Jorge E; Christofoletti, Cintya Ap; Ansoar-Rodríguez, Yadira; Guedes, Thays A; Fontanetti, Carmem S

2017-04-01

In Brazil vinasse, a main sugarcane distillery residue, stands out because every liter of alcohol generates 10-15 L of vinasse as waste. An alternative for the disposal of this waste is the fertirrigation of the sugarcane culture itself. However, the high amount released can saturate the soil and through leaching/percolation contaminate water resources. The aim of this study is verifying the toxic potential of vinasse in tilapias and effectiveness of the physicalchemical treatment of this waste with pH adjustment with lime (CaO). The comet assay and the micronucleus test were applied on animals exposed to dilutions of raw vinasse and vinasse adjusted to neutral pH. Bioassays with raw vinasse dilutions indicated a toxic and genotoxic potential; fish exposed to the highest concentration died less than 48 h after the exposure; the incidence of micronucleus was significantly higher when compared to negative control for all dilutions. For the comet assay, the scores of damage were statistically higher for all dilutions, with the exception of the 1% dillution. However, in the bioassay with the chemically treated vinasse (neutral pH), most fish in the 10% dilution survived and there was no significant difference when compared to the control. Damage scores in the comet assay were similar to the results of the untreated vinasse. The chemical treatment of vinasse with lime to neutralize the pH proved to be an effective alternative for the toxicity reduction of this residue, since it reduced the mortality of fish at higher concentrations and the incidence of damage to DNA. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular mechanisms of erythrocyte photo-irradiation

International Nuclear Information System (INIS)

Ferreira, W.T.; Souza, M.C.

1985-01-01

The role of singlet oxygen and the lipid peroxidation of erythrocyte membrane are studied. The irradiation of erythrocytes with visible light in the presence of a photodynamic mediator (toluidine blue) is reported. A system of light application by optical fiber, connected to a catheter is suggested for local instillation of the photosensitizing agent. (M.A.C.) [pt

Erythrocyte and platelet fatty acids in retinitis pigmentosa.

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Stanzial, A M; Bonomi, L; Cobbe, C; Olivieri, O; Girelli, D; Trevisan, M T; Bassi, A; Ferrari, S; Corrocher, R

1991-05-01

The fatty acid composition and the glutathione-peroxidase activity (GSH-Px) of erythrocytes and platelets, the production of malondialdehyde (MDA) by platelets and the activity of the main systems of transmembrane cation transport in erythrocyte have been studied in 12 patients (5 males and 7 females) affected by retinitis pigmentosa (RP). A remarkable increase of saturated fatty acids (SFA), particularly of stearic acid (C18:0), has been noted in these patients. The reduced unsaturated/saturated fatty acids ratio (PUFA/SFA) observed in both erythrocytes and platelets and the decrease of arachidonic acid in platelets may depend by an active peroxidation process as documented by the increase of MDA. Platelet glutathione-peroxidase (PTL-GSH-PX) and plasma retinol were in the normal range, whereas erythrocyte glutathione-peroxidase (E-GSH-PX), MDA and plasma alfa-toco-pherol were increased in patients with RP. The activities of Na(+)-K+ pump, cotransport and Na(+)-Li+ countertransport were normal in RP erythrocytes.

Hepatic or splenic targeting of carrier erythrocytes: a murine model

International Nuclear Information System (INIS)

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

1987-01-01

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 2 O 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 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

Human erythrocytes inhibit complement-mediated solubilization of immune complexes by human serum

International Nuclear Information System (INIS)

Dorval, B.L.

1987-01-01

The aim of this study was to develop an autologus human system to evaluate the effects of human erythrocytes on solubilization of immune complex precipitates (IC) by human serum. Incubation of IC with fresh human serum or guinea pig serum resulted in solubilization of IC. When packed erythrocytes were added to human serum or guinea pig serum binding of IC to the erythrocyte occurred and IC solubilization was inhibited significantly (p <.025). Sheep erythrocytes did not bind IC or inhibit IC solubilization. To evaluate the role of human erythrocyte complement receptor (CR1) on these findings, human erythrocytes were treated with trypsin or anti-CR1 antibodies. Both treatments abrogated IC binding to human erythrocytes but did not affect the ability of the human erythrocyte to inhibit IC solubilization. Radioimmunoassay was used to measure C3, C4 and C5 activation in human serum after incubation with IC, human erythrocytes, human erythrocytes plus IC, whole blood or in whole blood plus IC

Triggering of Suicidal Erythrocyte Death Following Boswellic Acid Exposure

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Salvatrice Calabrò

2015-08-01

Full Text Available Background/Aims: The antinflammatory natural product boswellic acid is effective against cancer at least in part by inducing tumor cell apoptosis. Similar to apoptosis of nucleated cells erythrocytes may enter eryptosis, a suicidal death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include oxidative stress, increase of cytosolic Ca2+-activity ([Ca2+]i, energy depletion, ceramide formation and p38 kinase activation. The present study tested, whether and how boswellic acid induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, ceramide abundance utilizing specific antibodies, reactive oxygen species (ROS from 2′,7′-dichlorodihydrofuorescein diacetate (DCFDA fluorescence, and cytosolic ATP concentration utilizing a luciferin-luciferase assay kit. Results: A 24 hours exposure of human erythrocytes to boswellic acid (5 µg/ml significantly increased the percentage of annexin-V-binding cells (to 9.3 ±0.9 % and significantly decreased forward scatter. Boswellic acid did not significantly modify [Ca2+]i, cytosolic ATP, ROS, or ceramide abundance. The effect of boswellic acid on annexin-V-binding was significantly blunted, but not abolished by p38 kinase inhibitors skepinone (2 µM and SB203580 (2 µM. Conclusions: Boswellic acid stimulates cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part dependent on p38 protein kinase activity.

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

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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.

Factors influencing erythrocyte choline concentrations.

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Miller, B L; Jenden, D J; Tang, C; Read, S

1989-01-01

Choline concentrations in human erythrocytes increase after freezing and thawing, during incubation in Krebs-phosphate for 30 min or on storage at 0 degrees C for 3-24 hr. The increase is prevented by protein precipitation by 10% perchloric acid, 10% zinc hydroxide, 10% sodium tungstate or boiling in water. It is not prevented by EDTA (10 mM) and is increased by oleate (5 mM). We suggest that the increase is due to the action of phospholipase D on erythrocyte phospholipids.

Genotoxicity testing of peptides: Folate deprivation as a marker of exaggerated pharmacology

International Nuclear Information System (INIS)

Guérard, Melanie; Zeller, Andreas; Festag, Matthias; Schubert, Christine; Singer, Thomas; Müller, Lutz

2014-01-01

The incidence of micronucleated-cells is considered to be a marker of a genotoxic event and can be caused by direct- or indirect-DNA reactive mechanisms. In particular, small increases in the incidence of micronuclei, which are not associated with toxicity in the target tissue or any structurally altering properties of the compound, trigger the suspicion that an indirect mechanism could be at play. In a bone marrow micronucleus test of a synthetic peptide (a dual agonist of the GLP-1 and GIP receptors) that had been integrated into a regulatory 13-week repeat-dose toxicity study in the rat, small increases in the incidence of micronuclei had been observed, together with pronounced reductions in food intake and body weight gain. Because it is well established that folate plays a crucial role in maintaining genomic integrity and pronounced reductions in food intake and body weight gain were observed, folate levels were determined from plasma samples initially collected for toxicokinetic analytics. A dose-dependent decrease in plasma folate levels was evident after 4 weeks of treatment at the mid and high dose levels, persisted until the end of the treatment duration of 13-weeks and returned to baseline levels during the recovery period of 4 weeks. Based on these properties, and the fact that the compound tested (peptide) per se is not expected to reach the nucleus and cause DNA damage, the rationale is supported that the elevated incidence of micronucleated polychromatic erythrocytes is directly linked to the exaggerated pharmacology of the compound resulting in a decreased folate level. - Highlights: • A synthetic peptide has been evaluated for potential genotoxicity • Small increases in an integrated (13-weeks) micronucleus test were observed • Further, animals had a pronounced reductions in food intake and body weight gain • A dose-dependent decrease in plasma folate levels was evident from week 4 onwards • Elevated micronuclei-incidence due to the

Induction of transient radioresistance in human erythrocytes

International Nuclear Information System (INIS)

Krokosz, Anita; Szweda-Lewandowska, Zofia

2006-01-01

Human erythrocytes suspended in an isotonic Na-phosphate buffer, pH 7.4 (hematocrit of 2%), were irradiated with γ-rays with single and split doses under air or N 2 O in order to determine the physicochemical changes caused by the dose inducing an increase in resistance to radiation-induced hemolysis. The obtained results showed that under the applied irradiation conditions, the dose of 0.4 kGy induced changes in erythrocytes, which were responsible for temporary resistance of erythrocytes to hemolysis. We concluded that the observed resistance is caused mainly by the structural changes in proteins

Antioxidant evaluation of heterocyclic compounds by cytokinesis-block micronucleus assay.

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Godevac, Dejan; Tesević, Vele; Vajs, Vlatka; Milosavljević, Slobodan; Stanković, Miroslava

2013-03-01

This article summarizes the results of using cytokinesis-block micronucleus (CBMN) assay to evaluate the antioxidant potential of heterocyclic compounds. Most studies were carried out with naturally occurring heterocyclic compounds such as plant polyphenols: flavonoids, xanthones, coumarins, and ellagitannins, or plant derived products (juices, extracts, supplements) rich in bioactive heterocyclic compounds. There are also some studies dealing with synthetic heterocyclic antioxidants. CBMN assay is an in vitro study that has been used to evaluate antioxidant and protective effects of heterocyclic compounds on induced chromosome aberration in human lymphocytes.

Erythrocyte metallothionein as an index of zinc status in humans

International Nuclear Information System (INIS)

Grider, A.; Bailey, L.B.; Cousins, R.J.

1990-01-01

Metallothionein concentrations in erythrocyte lysates derived from human subjects were measured by an ELISA procedure. IgG obtained from serum of sheep injected with human metallothionein 1 was used in this competitive assay. Subjects were fed a semipurified zinc-deficient diet for an 8-day depletion period after 3 days of acclimation. Fasting plasma zinc concentrations were reduced ∼7%. Metallothionein in the erythrocyte lysates was significantly decreased to 59% of the initial level by the end of the depletion period. Supplementation of these depleted subjects with zinc did not increase erythrocyte metallothionein levels within 24 hr. Daily supplementation of control subjects with zinc increased erythrocyte metallothionein to a 7-fold maximum within 7 days. These levels were reduced by 61% within 14 days after zinc supplementation was terminated. Incubation of rat [ 35 S]metallothionein with human erythrocyte lysate showed a time-dependent increase in 35 S soluble in 20% trichloroacetic acid, indicating degradation of the labeled protein, presumably via protease activity in the lysate. It is proposed that zinc supplementation induces erythrocyte metallothionein during erythropoiesis and that low zinc intake decreases synthesis and/or accelerates degradation of the protein in reticulocytes/erythrocytes. Metallothionein levels in erythrocytes may provide a useful index upon which to assess zinc status in humans

Transcriptomic Analysis of Young and Old Erythrocytes of Fish

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Miriam Götting

2017-12-01

Full Text Available Understanding gene expression changes over the lifespan of cells is of fundamental interest and gives important insights into processes related to maturation and aging. This study was undertaken to understand the global transcriptome changes associated with aging in fish erythrocytes. Fish erythrocytes retain their nuclei throughout their lifetime and they are transcriptionally and translationally active. However, they lose important functions during their lifespan in the circulation. We separated rainbow trout (Oncorhynchus mykiss erythrocytes into young and old fractions using fixed angle-centrifugation and analyzed transcriptome changes using RNA sequencing (RNA-seq technology and quantitative real-time PCR. We found 930 differentially expressed between young and old erythrocyte fractions; 889 of these showed higher transcript levels in young, while only 34 protein-coding genes had higher transcript levels in old erythrocytes. In particular genes involved in ion binding, signal transduction, membrane transport, and those encoding various enzyme classes are affected in old erythrocytes. The transcripts with higher levels in old erythrocytes were associated with seven different GO terms within biological processes and nine within molecular functions and cellular components, respectively. Our study furthermore found several highly abundant transcripts as well as a number of differentially expressed genes (DEGs for which the protein products are currently not known revealing the gaps of knowledge in most non-mammalian vertebrates. Our data provide the first insight into changes involved in aging on the transcriptional level and thus opens new perspectives for the study of maturation processes in fish erythrocytes.

Micronucleus test of varying amounts of potassium bromate (KBrO3) on the meristematic cells of Allium cepa var. aggregatum root tips

International Nuclear Information System (INIS)

Cajigal Romnick, M.; Somera, Leomerto A.

1999-03-01

Four hundred twenty onion bulbs of the multiplier variety Allium cepa var. aggregatum were used as test materials to assay the micronucleus induction capacity of potassium bromate doses of 0, 5, 10, 25, 50, 75, and 100 parts per million. Microscopic analyses were done using onion root tips prepared according to a modified technique of Medina (1994). These analyses were done on root tips taken from onions grown in KBrO 3 for three days and for five days. The study was conducted following a completely randomized design and the data were statistically analyzed using a non-parametric equivalent of the analysis of variance. A significant amount of micronucleated cells (MCN) were found among treated onions compared with the almost non-occurrence in the control groups (0 ppm). The Kruskal-Wallis H-test and the Wilcoxon two-samples tests revealed significant differences among treatment means and that a significant increase in the number of MCN occurs as the dose of KBr0 3 increased in both day experiments. Results from the higher doses of 50, 75, and 100 ppm were found to be significantly the same for the day 3 experiments while those of the day 5 higher doses are characterized by lack of clear cellular and nuclear outline such that scoring is difficult. Differences in MCN averages for the day 3 and 5 experiments appear to be insignificant. However, day 3 results show averages that are more significantly different from each other. These prove that the MCN can be used as an efficient and time-saving parameter for the allium test of chemicals with chromosome breaking capacities. (Author)

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

Erythrocyte enrichment in hematopoietic progenitor cell cultures based on magnetic susceptibility of the hemoglobin.

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Xiaoxia Jin

Full Text Available Using novel media formulations, it has been demonstrated that human placenta and umbilical cord blood-derived CD34+ cells can be expanded and differentiated into erythroid cells with high efficiency. However, obtaining mature and functional erythrocytes from the immature cell cultures with high purity and in an efficient manner remains a significant challenge. A distinguishing feature of a reticulocyte and maturing erythrocyte is the increasing concentration of hemoglobin and decreasing cell volume that results in increased cell magnetophoretic mobility (MM when exposed to high magnetic fields and gradients, under anoxic conditions. Taking advantage of these initial observations, we studied a noninvasive (label-free magnetic separation and analysis process to enrich and identify cultured functional erythrocytes. In addition to the magnetic cell separation and cell motion analysis in the magnetic field, the cell cultures were characterized for cell sedimentation rate, cell volume distributions using differential interference microscopy, immunophenotyping (glycophorin A, hemoglobin concentration and shear-induced deformability (elongation index, EI, by ektacytometry to test for mature erythrocyte attributes. A commercial, packed column high-gradient magnetic separator (HGMS was used for magnetic separation. The magnetically enriched fraction comprised 80% of the maturing cells (predominantly reticulocytes that showed near 70% overlap of EI with the reference cord blood-derived RBC and over 50% overlap with the adult donor RBCs. The results demonstrate feasibility of label-free magnetic enrichment of erythrocyte fraction of CD34+ progenitor-derived cultures based on the presence of paramagnetic hemoglobin in the maturing erythrocytes.

Erythrocyte membrane ATPase and calcium pumping activities in porcine malignant hyperthermia

International Nuclear Information System (INIS)

Thatte, H.S.; Mickelson, J.R.; Addis, P.B.; Louis, C.F.

1987-01-01

To investigate possible abnormalities in erythrocyte membrane enzyme activities in the pharmacogenetic disorder MH, membrane ATPase activities have been examined in erythrocyte ghosts prepared from red blood cells of MHS and normal swine. While no differences were noted in Mg2+-ATPase activities, the (Na+, K+)-ATPase activity of MHS erythrocyte ghosts was less than that of normal ghosts. Ca2+-ATPase activity exhibited low- and high-affinity Ca2+-binding sites in both types of erythrocyte ghost. While the Km for Ca2+ was greater for normal than for MHS erythrocyte ghosts at the high-affinity Ca2+-binding site, the reverse was true at the low-affinity Ca2+-binding site. Irrespective of the type of calcium binding site occupied, the Vmax for normal erythrocyte ghost Ca2+-ATPase activity was greater than that for MHS ghosts. In the presence of calmodulin, there was now no difference between MHS and normal erythrocyte ghosts in either the Km for Ca2+ or the Vmax of the Ca2+-ATPase activity. To determine if the calcium pumping activity of intact MHS and normal pig erythrocytes differed, calcium efflux from the 45 Ca-loaded erythrocytes was determined; this activity was significantly greater for MHS than for normal erythrocytes. Thus, the present study confirms that there are abnormalities in the membranes of MHS pig red blood cells. However, we conclude that these abnormalities are unlikely to result in an impaired ability of MHS erythrocytes to regulate their cytosolic Ca2+ concentration

Erythrocyte zinc levels in children with bronchial asthma.

Science.gov (United States)

Arik Yilmaz, E; Ozmen, S; Bostanci, I; Misirlioglu, E Dibek; Ertan, U

2011-12-01

Zinc deficiency may be suspected to play a role in the pathogenesis, control, and severity of asthma because of its antioxidant, antiapoptotic, and anti-inflammatory effects. We aimed to investigate whether there was any relationship between erythrocyte zinc levels and childhood asthma. The erythrocyte zinc levels of 67 asthmatic and 45 healthy children were analyzed in this case-control study. The mean concentrations of erythrocyte zinc were 1215.8 ± 145.1 µg/dl in asthma patients and 1206.9 ± 119.5 µg/dl in controls with no significant difference (P = 0.472). The erythrocyte zinc level was below 1,000 µg/dl in 6 asthmatic patients (8.9%) and 2 control group patients (4.4%). There was no relationship between erythrocyte zinc levels and duration of follow-up, severity, and control of the asthma (P > 0.05). On the other hand, patients hospitalized for an asthma attack had significantly lower erythrocyte zinc levels compared with nonhospitalized patients and the control group (P = 0.000 and P = 0.004 respectively). This study's findings indicate that asthmatic children are not a risk group for zinc deficiency. We emphasize that checking zinc levels in children who are hospitalized for an asthma attack may be useful. Copyright © 2011 Wiley Periodicals, Inc.

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...

Breed and species comparison of amino acid transport variation in equine erythrocytes.

Science.gov (United States)

Fincham, D A; Young, J D; Mason, D K; Collins, E A; Snow, D H

1985-05-01

The amino acid permeability of red blood cells from Equus caballus (thoroughbred, Arab, shire and pony), E przewalskii (Przewalski's horse), E asinus (donkey and mule) and E burchelli (common or plains zebra) was measured. Individual animals exhibited stable but widely differing rates of L-[U-14C]alanine uptake in the range 5 to 1554 mumol (litre cells)-1 h-1 (0.2 mM extracellular L-alanine, 37 degrees C). Of the thoroughbreds tested, 30 per cent had red blood cells which were essentially impermeable to L-alanine (5 to 10 mumol (litre cells)-1 h-1, giving transport rates similar to those found previously in amino acid transport-deficient sheep erythrocytes. In contrast, only 3 per cent of the ponies tested had red blood cells impermeable to L-alanine. No cases of erythrocyte amino acid transport deficiency were found in the other horse breeds and species tested.

Deformability of Erythrocytes and Oxidative Damage in Alzheimer Disease

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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

Ferrokinetic and erythrocyte survival studies in healthy and anemic cats

Energy Technology Data Exchange (ETDEWEB)

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

1983-03-01

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

Ferrokinetic and erythrocyte survival studies in healthy and anemic cats

International Nuclear Information System (INIS)

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

1983-01-01

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

State of the Art High-Throughput Approaches to Genotoxicity: Flow Micronucleus, Ames II, GreenScreen and Comet

Science.gov (United States)

State of the Art High-Throughput Approaches to Genotoxicity: Flow Micronucleus, Ames II, GreenScreen and Comet (Presented by Dr. Marilyn J. Aardema, Chief Scientific Advisor, Toxicology, Dr. Leon Stankowski, et. al. (6/28/2012)

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.

Nucleoplasmic bridges are a sensitive measure of chromosome rearrangement in the cytokinesis-block micronucleus assay

International Nuclear Information System (INIS)

Fenech, M.; Umegaki, K.

2003-01-01

Full text: We have performed experiments using the WIL2-NS human B-lymphoblastoid cell line and primary human lymphocytes to (a) determine the importance of including measurements of nucleoplasmic bridges (NPB) in the cytokinesis-block micronucleus (CBMN) assay and (b) provide evidence that NPB originate from dicentric chromosomes and centric ring chromosomes. In addition we describe theoretical models that explain how dicentric chromosomes and centric ring chromosomes may result in the formation of NPB at anaphase. The results with WIL2-NS showed that it was possible to distinguish genotoxic effects induced by different oxidizing agents in terms of the NPB/micronucleus frequency ratio. The results with lymphocytes indicated a strong correlation (a) between NPB, centric ring chromosomes and dicentric chromosomes in metaphases (R>0.93, P 0.93, P<0.0001). The dose-response curves with gamma rays were very similar for NPB, ring chromosomes and dicentric chromosomes, as were the dose-responses for MNi, acentric rings and fragments. However, not all acentric chromosomes and dicentric chromosomes/centric rings were converted to MNi and NPB respectively, depending on the dose of radiation. Preliminary data, using FISH, suggests that NPB often represent DNA from a structural rearrangement involving only one or two homologous chromosomes. The results from this study validate the inclusion of NPB in the CBMN assay which provides a valuable measure of chromosome breakage/ rearrangement that was otherwise not available in the micronucleus assay. The CBMN assay allows NPB measurement to be achieved reliably because inhibition of cytokinesis prevents the loss of NPB that would otherwise occur if cells were allowed to divide

Influence of styryl dyes on blood erythrocytes

Science.gov (United States)

Nizomov, Negmat; Barakaeva, Mubaro; Kurtaliev, Eldar N.; Rahimov, Sherzod I.; Khakimova, Dilorom P.; Khodjayev, Gayrat; Yashchuk, Valeriy N.

2008-08-01

It was studied the influence of F, Sbt, Sil, Sbo monomer and homodimer Dst-5, Dst-10, Dbt-5, Dbt-10, Dil-10, Dbo-10 styryl dyes on blood erythrocytes of white rats. It was shown that the homodimer styryl dyes Dst-5, Dbt-5 and Dbo-10 decrease the erythrocytes quantity by 1.5-2 times more as compared with monomer dyes Sbt and Sbo. The main cause of dyes different action is the different oxidation degree of intracellular hemoglobin evoked by these dyes. It was established that the observed effects was connected with different penetration of these dyes through membrane of erythrocytes and with interaction of these dyes with albumin localized in membranes of cells.

The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis

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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.

Micronucleus Assay and Heavy Metals Characterization of E-waste ...

African Journals Online (AJOL)

ADOWIE PERE

2018-03-28

Mar 28, 2018 ... Ba) in the sediments, water, leachate and aquatic fauna (Tilapia guineensis, Callinectes amnicola and Cardiosoma ..... (2003) limit standard (0.01mg/L) for treated waste water .... the erythrocyte of grey mullet (Mugil cephalus).

The effect of gamma radiation on the Common carp (Cyprinus carpio): In vivo genotoxicity assessment with the micronucleus and comet assays.

Science.gov (United States)

M K, Praveen Kumar; Soorambail K, Shyama; Bhagatsingh Harisingh, Sonaye; D'costa, Avelyno; Ramesh Chandra, Chaubey

2015-10-01

Radioactive wastes may be leached into freshwater, either accidentally or in industrial effluents. We have studied gamma radiation-induced DNA damage in the freshwater fish Cyprinus carpio. Fish were irradiated with 2-10Gy gamma radiation and genotoxic effects in blood cells were studied with the micronucleus (MN) and comet assays. Micronuclei and a dose-dependent increase in comet-tail DNA were seen in dose- and time-dependent studies. The highest % tail DNA was observed at 24h, declining until 72h, which may indicate the repair of radiation-induced DNA single-strand breaks after gamma radiation. However, double-stranded DNA damage may not have been repaired, as indicated by increased micronuclei at later periods. A positive correlation was observed between the comet and micronucleus assay results. This study confirms the mutagenic/genotoxic potential of gamma radiation in the Common carp, as well as the possible combined use of the micronucleus and comet assays for in vivo laboratory studies with fresh-water fish for screening the genotoxic potential of radioactive pollution. Copyright © 2015 Elsevier B.V. All rights reserved.

Significance of the proportion of binucleate cells in the micronucleus assay; A methodological study

Energy Technology Data Exchange (ETDEWEB)

Imamura, Masahiro; Edgren, M.R. (Karolinska Inst., Stockholm (Sweden). Dept. of Radiation Physics)

1994-03-01

Using treatment with cytochalasin-B (Cyt-B) for the induction of a cytokinetic block, the significance of the proportion of binucleate cells (BNC) in the micronucleus (MN) assay was investigated in a methodological study. A Chinese hamster cell line V79 was used in which MN were induced by radiation. In complementary tests the radiation effect in inducing MN was enhanced by depletion of the cellular glutathione content with buthionine sulfoximine (BSO). The data indicated that the concentration of Cyt-B is the major factor which determines the proportion of BNC. This proportion was shown to be independent of radiation dose and of BSO. Furthermore, the MN frequency was not related to the percentage of BNC. Therefore, a high proportion of BNC may be practical for the MN assay, but may not make the technique more accurate. (author).

Assessment of the genotoxic impact of pesticides on farming communities in the countryside of Santa Catarina State, Brazil

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Jaqueli Salvagni

2011-01-01

Full Text Available The aim of this study was to assess the use of pesticides on farms located in the Lambedor River watershed in Guatambu, State of Santa Catarina, as well as to determine, by micronucleus testing, the risk of genotoxic impact. Samples from locally collected Cyprinus carpio, Hypostomus punctatus, Rhamdia quelen and Oreochromis niloticus gave evidence of a mean increase in micronuclei frequency from 6.21 to 13.78 in 1,000 erythrocytes, a clear indication of the genotoxic potenciality of pesticide residues in regional dams, and their significant contribution to local environmental contamination.

Combination of physico-chemical analysis, Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay/nuclear abnormalities tests for cyto-genotoxicity assessments of treated effluents discharged from textile industries.

Science.gov (United States)

Hemachandra, Chamini K; Pathiratne, Asoka

2016-09-01

Bioassays for cyto-genotoxicity assessments are generally not required in current textile industry effluent discharge management regulations. The present study applied in vivo plant and fish based toxicity tests viz. Allium cepa test system and Oreochromis niloticus erythrocyte based comet assay and nuclear abnormalities tests in combination with physico-chemical analysis for assessing potential cytotoxic/genotoxic impacts of treated textile industry effluents reaching a major river (Kelani River) in Sri Lanka. Of the treated effluents tested from two textile industries, color in the Textile industry 1 effluents occasionally and color, biochemical oxygen demand and chemical oxygen demand in the Textile industry 2 effluents frequently exceeded the specified Sri Lankan tolerance limits for discharge of industrial effluents into inland surface waters. Exposure of A. cepa bulbs to 100% and 12.5% treated effluents from both industries resulted in statistically significant root growth retardation, mito-depression, and induction of chromosomal abnormalities in root meristematic cells in comparison to the dilution water in all cases demonstrating cyto-genotoxicity associated with the treated effluents. Exposure of O. niloticus to the 100% and 12.5% effluents, resulted in erythrocytic genetic damage as shown by elevated total comet scores and induction of nuclear abnormalities confirming the genotoxicity of the treated effluents even with 1:8 dilution. The results provide strong scientific evidence for the crucial necessity of incorporating cyto-genotoxicity impact assessment tools in textile industry effluent management regulations considering human health and ecological health of the receiving water course under chronic exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

Erythrocyte Membrane Failure by Electromechanical Stress

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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.

Micronucleus test of varying amounts of potassium bromate (KBrO{sub 3}) on the meristematic cells of Allium cepa var. aggregatum root tips

Energy Technology Data Exchange (ETDEWEB)

Cajigal Romnick, M; Somera, Leomerto A

1999-03-01

Four hundred twenty onion bulbs of the multiplier variety Allium cepa var. aggregatum were used as test materials to assay the micronucleus induction capacity of potassium bromate doses of 0, 5, 10, 25, 50, 75, and 100 parts per million. Microscopic analyses were done using onion root tips prepared according to a modified technique of Medina (1994). These analyses were done on root tips taken from onions grown in KBrO{sub 3} for three days and for five days. The study was conducted following a completely randomized design and the data were statistically analyzed using a non-parametric equivalent of the analysis of variance. A significant amount of micronucleated cells (MCN) were found among treated onions compared with the almost non-occurrence in the control groups (0 ppm). The Kruskal-Wallis H-test and the Wilcoxon two-samples tests revealed significant differences among treatment means and that a significant increase in the number of MCN occurs as the dose of KBr0{sub 3} increased in both day experiments. Results from the higher doses of 50, 75, and 100 ppm were found to be significantly the same for the day 3 experiments while those of the day 5 higher doses are characterized by lack of clear cellular and nuclear outline such that scoring is difficult. Differences in MCN averages for the day 3 and 5 experiments appear to be insignificant. However, day 3 results show averages that are more significantly different from each other. These prove that the MCN can be used as an efficient and time-saving parameter for the allium test of chemicals with chromosome breaking capacities. (Author)

Erythrocyte signal transduction pathways, their oxygenation dependence and functional significance.

Science.gov (United States)

Barvitenko, Nadezhda N; Adragna, Norma C; Weber, Roy E

2005-01-01

Erythrocytes play a key role in human and vertebrate metabolism. Tissue O2 supply is regulated by both hemoglobin (Hb)-O2 affinity and erythrocyte rheology, a key determinant of tissue perfusion. Oxygenation-deoxygenation transitions of Hb may lead to re-organization of the cytoskeleton and signalling pathways activation/deactivation in an O2-dependent manner. Deoxygenated Hb binds to the cytoplasmic domain of the anion exchanger band 3, which is anchored to the cytoskeleton, and is considered a major mechanism underlying the oxygenation-dependence of several erythrocyte functions. This work discusses the multiple modes of Hb-cytoskeleton interactions. In addition, it reviews the effects of Mg2+, 2,3-diphosphoglycerate, NO, shear stress and Ca2+, all factors accompanying the oxygenation-deoxygenation cycle in circulating red cells. Due to the extensive literature on the subject, the data discussed here, pertain mainly to human erythrocytes whose O2 affinity is modulated by 2,3-diphosphoglycerate, ectothermic vertebrate erythrocytes that use ATP, and to bird erythrocytes that use inositol pentaphosphate. Copyright 2005 S. Karger AG, Basel.

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

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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.

Effect of gamma radiation on the concentration of pyruvate and lactate in erythrocytes of healthy men after submaximal physical exercise

International Nuclear Information System (INIS)

Zagorski, T.; Dudek, I.; Berkan, L.; Chmielewski, H.; Kedziora, J.

1993-01-01

The aim of this work was to study the effect of gamma radiation and submaximal physical exercise on the concentration of final products of anaerobic glycolytic pathway in erythrocytes of healthy men. Twenty one men aged 20-22 were examined. They underwent physical exercise at doses of 2 w/kg body weight for 15 min. Erythrocytes were taken in the rest and after physical exercise and were exposed to gamma radiation (500 Gy doses) from 60 Co source. The concentration of pyruvate was estimated by Fermognost tests and the concentration of lactate by Boehringer Mannheim tests. The submaximal physical exercise was found to cause a significantly increased concentration of pyruvate and lactate in the non-radiated and irradiated erythrocytes. Gamma radiation at 500 Gy dose was found to increase concentration of pyruvate in erythrocytes (in the rest and after physical exercise) with simultaneous decrease of lactate concentration. (author). 17 refs, 1 tab

Rubidium contents in erythrocyte of children, rice and soil in the areas with different selenium status

International Nuclear Information System (INIS)

Liu Nianqing; Zhao Shunying; Qian Qinfang; Zhu Lianzhen; Piao Jianhua

1997-01-01

Rubidium concentration of erythrocyte of healthy children aged from 6-11 years living in four areas of Sichuan Province with different selenium status was measured by PIXE and the results show that the Rb concentration in erythrocyte for the Keshan Disease area is two times more than other three areas. Meanwhile the glutathione peroxidase (GSHPx) activity of erythrocyte was determined and the results confirm that children in the Keshan Disease area are really with selenium deficiency. The Rb contents in rice and soil samples from the Keshan Disease area and the Se-deficiency area but with Se-supplementation to the inhabitants, were tested by INNA. It was found that Rb contents in rice and soil from the former area were much higher than those from the latter. This result indicates that Rb in erythrocyte of children is mainly taken from staple food (rice) and that a higher Rb level in soil is probably another environmental factor causing the Keshan Disease

Paired Chicken and Mammalian Erythrocyte Indicator Systems for ...

African Journals Online (AJOL)

A retrospective flock health analysis revealed that the higher titres were associated with confirmable Newcastle Disease (ND) outbreaks in the affected flocks. These findings therefore suggested that the use of standardised guinea pig erythrocytes in parallel with chicken erythrocytes as indicators, might facilitate field ND ...

Genotoxic potential generated by biomass burning in the Brazilian Legal Amazon by Tradescantia micronucleus bioassay: a toxicity assessment study

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Artaxo Paulo

2011-05-01

Full Text Available Abstract Background The Brazilian Amazon has suffered impacts from non-sustainable economic development, especially owing to the expansion of agricultural commodities into forest areas. The Tangará da Serra region, located in the southern of the Legal Amazon, is characterized by non-mechanized sugar cane production. In addition, it lies on the dispersion path of the pollution plume generated by biomass burning. The aim of this study was to assess the genotoxic potential of the atmosphere in the Tangará da Serra region, using Tradescantia pallida as in situ bioindicator. Methods The study was conducted during the dry and rainy seasons, where the plants were exposed to two types of exposure, active and passive. Results The results showed that in all the sampling seasons, irrespective of exposure type, there was an increase in micronucleus frequency, compared to control and that it was statistically significant in the dry season. A strong and significant relationship was also observed between the increase in micronucleus incidence and the rise in fine particulate matter, and hospital morbidity from respiratory diseases in children. Conclusions Based on the results, we demonstrated that pollutants generated by biomass burning in the Brazilian Amazon can induce genetic damage in test plants that was more prominent during dry season, and correlated with the level of particulates and elevated respiratory morbidity.

Erythrocyte survival studies in a rat myelogenous leukemia

International Nuclear Information System (INIS)

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

1982-01-01

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

The reference range of serum, plasma and erythrocyte magnesium

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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

In Vitro Protective Effect of Phikud Navakot Extraction on Erythrocyte

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Kanchana Kengkoom

2016-01-01

Full Text Available Phikud Navakot (PN, Thai herbal remedy in National List of Essential Medicines, has been claimed to reduce many cardiovascular symptoms especially dizziness and fainting. Apart from blood supply, erythrocyte morphology, in both shape and size, is one of the main consideration factors in cardiovascular diseases and may be affected by vascular oxidative stress. However, little is known about antioxidative property of PN on erythrocyte to preserve red blood cell integrity. In this study, 1,000 μM hydrogen peroxide-induced oxidative stress was conducted on sheep erythrocyte. Three doses of PN (1, 0.5, and 0.25 mg/mL and 10 μM of ascorbic acid were compared. The released hemoglobin absorbance was measured to demonstrate hemolysis. Electron microscopic and immunohistochemical studies were also performed to characterize dysmorphic erythrocyte and osmotic ability in relation to aquaporin- (AQP- 1 expression, respectively. The results revealed that all doses of PN and ascorbic acid decreased the severity of dysmorphic erythrocyte, particularly echinocyte, acanthocyte, knizocyte, codocyte, clumping, and other malformations. However, the most effective was 0.5 mg/mL PN dosage. In addition, hydrostatic pressure may be increased in dysmorphic erythrocyte in association with AQP-1 upregulation. Our results demonstrated that PN composes antioxidative effect to maintain the integrity and osmotic ability on sheep erythrocyte.

Erythrocyte nanovesicles: Biogenesis, biolo

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Gamaleldin I. Harisa

2017-01-01

Full Text Available Nanovesicles (NVs represent a novel transporter for cell signals to modify functions of target cells. Therefore, NVs play many roles in both physiological and pathological processes. This report highlights biogenesis, composition and biological roles of erythrocytes derived nanovesicles (EDNVs. Furthermore, we address utilization of EDNVs as novel drug delivery cargo as well as therapeutic target. EDNVs are lipid bilayer vesicles rich in phospholipids, proteins, lipid raft, and hemoglobin. In vivo EDNVs biogenesis is triggered by an increase of intracellular calcium levels, ATP depletion and under effect of oxidative stress conditions. However, in vitro production of EDNVs can be achieved via hypotonic treatment and extrusion of erythrocyte. NVs can be used as biomarkers for diagnosis, monitoring of therapy and drug delivery system. Many therapeutic agents are suggested to decrease NVs biogenesis.

Genotoxic and Antigenotoxic Assessment of Chios Mastic Oil by the In Vitro Micronucleus Test on Human Lymphocytes and the In Vivo Wing Somatic Test on Drosophila.

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Dimitris Vlastos

Full Text Available Chios mastic oil (CMO, the essential oil derived from Pistacia lentiscus (L. var. chia (Duham, has generated considerable interest because of its antimicrobial, anticancer, antioxidant and other beneficial properties. In the present study, the potential genotoxic activity of CMO as well as its antigenotoxic properties against the mutagenic agent mitomycin-C (MMC were evaluated by employing the in vitro Cytokinesis Block MicroNucleus (CBMN assay and the in vivo Somatic Mutation And Recombination Test (SMART. In the in vitro experiments, lymphocytes were treated with 0.01, 0.05 and 0.10% (v/v of CMO with or without 0.05 μg/ml MMC, while in the in vivo assay Drosophila larvae were fed with 0.05, 0.10, 0.50 and 1.00% (v/v of CMO with or without 2.50 μg/ml MMC. CMO did not significantly increase the frequency of micronuclei (MN or total wing spots, indicating lack of mutagenic or recombinogenic activity. However, the in vitro analysis suggested cytotoxic activity of CMO. The simultaneous administration of MMC with CMO did not alter considerably the frequencies of MMC-induced MN and wing spots showing that CMO doesn't exert antigenotoxic or antirecombinogenic action. Therefore, CMO could be considered as a safe product in terms of genotoxic potential. Even though it could not afford any protection against DNA damage, at least under our experimental conditions, its cytotoxic potential could be of interest.

Comparison of micronucleus frequencies and proliferation kinetics in three X-irradiated cell lines

International Nuclear Information System (INIS)

Kaffenberger, W.; Becker, K.; Beuningen, D. van

1990-01-01

The kinetics of the occurrence of micronuclei was correlated with the survival of three mammalian cell lines of human, monkey, and mouse origin after irradiation with 240 kV X-rays. Particular attention was paid to the evaluation of the individual proliferation kinetics of the cell lines as well as to the characterization of micronuclei subpopulation with respect to size and possible biological importance using DNA and BUdR labelling techniques, fluorescence microscopy, and image analysis. The results demonstrate very characteristic size distributions of micronuclei for the three cell lines independent of radiation dose and time after irradiation. A close correlation between cell death and the occurrence of micronuclei (expressed as a calculated 'MN index') after irradiation could be established only when the kinetics of progression of cells through the cell cycle (e.g. the doubling time) and the biological characteristics of micronuclei (e.g. BUdR positivity, the micronucleus frequencies, and the number of micronuclei per main nucleus) were taken into account. Therefore, the micronucleus assay might not be useful as a quantitative perdictive assay in vivo but may allow qualitative estimations of radiation damage only because the necessary proliferation parameters of the cells might not be possible to establish in vivo. (orig.) [de

Subcutaneous administration of carrier erythrocytes: slow release of entrapped agent

International Nuclear Information System (INIS)

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

1988-01-01

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 [ 14 C]sucrose, [ 3 H]inulin, and 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 [ 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

Intraspecific variation in erythrocyte sizes among populations of Hypsiboas cordobas (Anura: Hylidae

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Mariana Baraquet

2013-12-01

Full Text Available We studied the morphology and size of erythrocytes of H. cordobae, and analysed the geographic variation of this character along the distribution of the species, in relation to the latitudinal and altitudinal distances. Erythrocyte shape of the H. cordobae is ellipsoidal and the nuclei are also ellipsoidal and centrally oriented. Erythrocyte and nuclear size showed significant differences among populations, with the highest mean size corresponding to the population of Achiras (low altitude site and the lowest mean size to Los Linderos (high altitude site. There was no significant relationship between the latitude of each population and the both erythrocyte and nuclear size. The altitudinal variation in erythrocyte cell size may be attributable to the surface available for gas exchange; a small erythrocyte offers a possibility of greater rate of exchange than a larger one. Our results are consistent with studies of other amphibians, where intraspecific comparisons of populations at different altitudes show that individuals at higher altitudes are characterized by smaller erythrocytes.

[Protective Effect of S-isopentenyl-L-cysteine against DNA Damage in Irradiated Mice].

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Zheng, Qi-sheng; Yu, Guang-yun; He, Xin; Jiang, Ming; Chu, Xiao-fei; Zhao, Shu-yi; Fan, Sai-jun; Liu, Pei-xun

2015-10-01

To evaluate the protective effect of S-isopentenyl-L-cysteine,a new cysteine derivative,on DNA damage induced by radiation by using acute radiation injury animal models. Forty ICR mice were randomly divided into five groups:the control group,1.0Gy gamma irradiation group,1.0Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,7.2Gy gamma irradiation group,and 7.2Gy gamma irradiation combined with S-isopentenyl-L-cysteine group,with 8 mice in each group.The comet assay and bone marrow polychromatic micronucleus experiments were performed to evaluate the double-strand DNA breaks in ICR mice exposed to 1.0 and 7.2Gy gamma-ray, respectively. The tail DNA percentage,tail length,tail moment,and olive tail moment of peripheral blood lymphocytes in 7.2Gy gamma irradiation group were significantly higher than that of the control group (PL-cysteine group was significantly less than that of 7.2Gy gamma irradiation group (PL-cysteine before irradiation,the micronucleus rate of ICR mice exposed to 1.0 and 7.2Gy gamma-ray decreased from (39.5000 ± 3.3141)‰ to (28.1667±4.1345)‰ (P=0.033) and from (76.5000 ± 4.6242)‰ to (22.8333 ± 3.6553)‰(P=0.000),respectively. The bone marrow polychromatic micronucleus experiment indicated that the value of polychromatic erythrocyte (PCE)/normochromatic erythrocyte(NCE) of ICR mice exposed to 1.0 and 7.2Gy gamma-ray was less than the control group(PL-cysteine before irradiation was significantly higher than the corresponding groups (PL-cysteine has a good protective effect against DNA damage induced by radiation.

Detection of Occult Erythrocytic Membrane Damages upon Pharmacological Exposures

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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. 

Evaluation of genotoxicity after application of Listerine(R) on human lymphocytes by micronucleus and single cell gel electrophoresis assays.

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Türkez, Hasan; Togar, Basak; Arabaci, Taner

2012-04-01

Listerine (LN) is one of the most commonly used mouth rinses worldwide although very limited information is available concerning its genotoxicity. In another view, the biological safety profile of oral care products is frequently assumed on the basis of simplistic test models. Therefore, the present study was undertaken to investigate the in vitro genotoxic potential of LN using micronucleus and single cell gel electrophoresis tests as genetic endpoints. Different concentrations of LN (0-100% of ml/culture, v/v) were applied to whole human blood cultures (n = 5). The result of the present study showed that there were no statistically significant differences (p > 0.05) between the control group and the groups treated with LN alone in both analysed endpoints. In conclusion, our result first demonstrated the absence of genotoxicity of LN on human lymphocytes.

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...

Effects of Rambutan Peel Extract to The Number of Erythrocytes and Haemoglobin in Rats Exposed to Cigarette Smoke

Science.gov (United States)

Lisdiana; Dewi, F. K.

2017-04-01

Cigarette smoke is one of the exogenous free radicals sources. When it is inhaled, its activity may damage the structure of erythrocyte membrane function. The impacts of free radicals can be reduced through the provision of antioxidants. Rambutan fruit peel contains the phenolic compound in the form of polyphenols that are antioxidants. The purpose of this study is to determine the effect of rambutan fruit peel extracts to the number of erythrocytes and haemoglobin in rats exposed to cigarette smoke. This design used Post Test Control Group Design. A sample of 25 rats was divided into five groups, each group consisting of 5 rats. The positive control group (K+) were given a standard food and drinking water. The negative control group (K) by three cigarettes, the treatment group (KP1, KP2, KP3) by three cigarettes and skin extract of rambutan each treatment group with a dose 15 mg/kg, 30 mg/kg and 45 mg/kg for 30 days. Data on the number of erythrocytes and haemoglobin in rat blood was analysed with LSD and to determine the optimum dosage was analysed by using regression test. Research results shown that the content of rambutan fruit peel extract may increase the number of erythrocytes and haemoglobin of blood. Conclusions from this research are the rambutan fruit peel extract at a dose of 45 mg/kg body weight can increase and maintain the number of erythrocytes and haemoglobin in the blood of rat exposed to cigarette smoke.

Plasmodium falciparum-infected erythrocytes do not adhere well to C32 melanoma cells or CD36 unless rosettes with uninfected erythrocytes are first disrupted.

OpenAIRE

Handunnetti, S M; Hasler, T H; Howard, R J

1992-01-01

Plasmodium falciparum malaria parasites modify the human erythrocytes in which they grow so that some parasitized erythrocytes (PE) can cytoadhere (C+) to host vascular endothelial cells or adhere in rosettes (R+) to uninfected erythrocytes. These C+ and R+ adherence properties of PE appear to mediate much of the pathogenesis of severe malaria infections, in part by blocking blood flow in microvessels. From one parasite strain, PE were selected in vitro for C+ R+ or C+ R- adherence properties...

Delayed effects of radiation on enzymes in erythrocytes

International Nuclear Information System (INIS)

Li Jinying; Zhang Weiping; Liu Benti

1998-01-01

Objective: To study the delayed effects of radiation on the enzymes in erythrocytes. Methods: The activity of 8 enzymes, related glycolysis, hexose monophosphate shunt, nucleotide metabolism, redox reaction and esterase in erythrocytes of five patients with bone marrow form of acute radiation sickness (ARS) were assayed at 1,2,3 and 6 years after exposure to 60 Co radiation. Results: The decreased activities of glucose-6-phosphate dehydrogenase (G6PD), pyruvate kinase (PK), NADH-methemoglobin reductase (MR) during the stage of crisis and of acetylcholinesterase (ACE) during the stage of convalescence were recovered to varying extent, whereas the lowered activities of the first three enzymes in some cases remained unchanged. There was no correlation between the enzyme activity and the radiation dose as well as the age of the patients. Conclusion: It is demonstrated that the delayed effects of radiation damage to erythrocyte enzymes are most significant in PK of glycolysis, G6PD of hexose monophosphate shunt and MR of redox reaction. It is suggested that the genes related to the synthesis of erythrocyte enzymes may be damaged by radiation

Isolation of low-molecular-weight lead-binding protein from human erythrocytes

International Nuclear Information System (INIS)

Raghavan, S.R.V.; Gonick, H.C.

1977-01-01

In blood, lead is mainly associated with erythrocytes and only a very small amount is found in plasma. Previously it was thought that the lead was bound to the erythrocyte cell membrane but more recently it has been observed that lead is bound primarily to the cell contents, ostensibly hemoglobin. In examining the lead-binding properties of normal human erythrocytes and those of lead-exposed industrial workers, we have found that, whereas lead binds only to hemoglobin in normal erythrocytes, there is also appreciable binding of lead to a low-molecular weight-protein in erythrocytes from lead-exposed workers. The synthesis of this protein may be induced by lead exposure. The 10,000 molecular weight protein may act as a storage site and mechanism for segregating lead in a non-toxic form

Adenosine deaminase activity of erythrocytes in hyperuricemia

International Nuclear Information System (INIS)

Krueger, W.; Richter, V.; Beenken, O.; Weinhold, D.; Hirschberg, K.; Rotzsch, W.; Akademie der Wissenschaften der DDR, Leipzig. Zentralinstitut fuer Isotopen- und Strahlenforschung)

1982-01-01

Erythrocytic adenosine deaminase (ADA) activity was determined in 55 patients with primary hyperuricemia and in 37 healthy control persons. Unlike the controls, the ADA activity in the patient group showed a two-peak response. Hyperuricemia patients with high ADA activity also exhibited increased uric acid excretion and elevated 15 N incorporation into uric acid. High activity values of erythrocytic ADA can be interpreted as an uric acid overproduction, giving hints for a therapeutic plan. (author)

Stimulation of Suicidal Erythrocyte Death by Increased Extracellular Phosphate Concentrations

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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.

Effects of estradiol and progesterone on the variability of the micronucleus assay

International Nuclear Information System (INIS)

Baeyens, Ans; Vandersickel, Veerle; Thierens, Hubert; Ridder, Leo De; Vral, Anne

2005-01-01

To investigate chromosomal radiosensitivity of lymphocytes the micronucleus (MN) assay has been used for many years. The results of these studies suggest the use of the MN assay as a biomarker for cancer predisposition. However, the MN assay has still some limitations associated with the reproducibility and sensitivity. Especially a high intra-individual variability has been observed. An explanation for this high intra-individual variability is not yet available. In literature it is suggested that the high variability among females is attributable to hormonal status. In this study we investigated if the high intra-individual variability in micronucleus formation in lymphocytes of females after in vitro exposure to ionising radiation is caused by variations in hormone levels of estradiol (E2) and progesterone (PROG). For this, the MN assay was performed on blood samples of 18 healthy women during 7 consecutive weeks while the estradiol and progesterone levels were determined at the same time. The MN assay was also examined in cultures of isolated blood lymphocytes with estradiol or progesterone levels added in vitro. The results demonstrated that estradiol and progesterone levels have no influence on the variations in radiation-induced MN yields observed in blood samples of healthy women. These conclusions were confirmed by the 'in vitro' experiments as no correlation between the MN yields and the concentrations of hormones (estradiol or progesterone) added in vitro to isolated lymphocytes cultures was observed

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 pr....... The identification of PfEMP1 domains expressed by parasites causing disease in infants and young children is important for development of vaccines protecting against severe malaria.......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...... previously been suggested that parasites expressing group A or B/A PfEMP1s are most pathogenic. To test the hypothesis that the first malaria infections in infants and young children are dominated by parasites expressing A and B/A PfEMP1s, we measured the plasma Ab level against 48 recombinant PfEMP1 domains...

Stimulation of ceramide formation and suicidal erythrocyte death by vitamin K(3) (menadione).

Science.gov (United States)

Qadri, Syed M; Eberhard, Matthias; Mahmud, Hasan; Föller, Michael; Lang, Florian

2009-11-25

Vitamin K(3) is an essential micronutrient required for the activation of coagulation factors and thus hemostasis. Administration of vitamin K(3) analogues may cause anemia, which at least in theory could be due to stimulation of suicidal erythrocyte death or eryptosis characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane leading to exposure of phosphatidylserine at the erythrocyte surface. Eryptosis is triggered by an increase in the cytosolic Ca(2+) activity, by ceramide and by energy depletion (decrease of cytosolic ATP). The present experiments explored, whether vitamin K(3) may influence eryptosis. Hemolysis was estimated from the supernatant hemoglobin concentration, phosphatidylserine-exposing erythrocytes from annexin V-binding in fluorescence-activated cell sorter (FACS) analysis, erythrocyte volume from forward scatter in FACS analysis, ceramide formation from binding of fluorescent antibodies, and erythrocyte ATP content from a luciferin-luciferase assay. As a result, vitamin K(3) (> or =1microM) caused lysis of an only small fraction of erythrocytes, but significantly increased ceramide formation, significantly increased the percentage of annexin V-binding erythrocytes, significantly decreased forward scatter and, at higher concentrations, significantly decreased the cellular ATP content. In conclusion, vitamin K(3) stimulates suicidal erythrocyte death, an effect at least partially due to ceramide formation and ATP depletion.

L-Sorbose but not D-tagatose induces hemolysis of dog erythrocytes in vitro.

Science.gov (United States)

Bär, A; Leeman, W R

1999-04-01

Previous investigations have demonstrated that L-sorbose induces hemolysis of dog erythrocytes. This effect is probably the consequence of an ATP depletion of the red blood cells subsequent to inhibition of hexokinase, and thus the glycolytic pathway, by sorbose 1-phosphate. In the present study, the susceptibility of dog erythrocytes to D-tagatose, a stereoisomer of L-sorbose, was examined. Washed dog erythrocytes were suspended in Hanks' balanced salt solution (HBSS, containing 5.6 mM glucose) with or without the addition of 0.6, 6, and 60 mM L-sorbose or D-tagatose, or in HBSS with total glucose concentrations of 5.6, 6 and 60 mM D-glucose. After incubation for 24 h at 34 degrees C, the suspensions were centrifuged, and the percentage of hemolysis was determined by measuring the hemoglobin in the sediment and the supernatant. The amount of hemoglobin released in the medium did not differ significantly between the control (HBSS) and the test incubations with glucose or D-tagatose supplementation. In contrast, the addition of 6 and 60 mM L-sorbose resulted in significant hemolysis. At the low dose (0.6 mM), L-sorbose did not have an adverse effect. It is concluded that D-tagatose, unlike L-sorbose, does not have a hemolytic effect on canine erythrocytes. Copyright 1999 Academic Press.

Physiological variations in levels of 2,3-diphosphoglycerate in horse erythrocytes.

Science.gov (United States)

Lewis, I M; McLan, J G

1975-03-01

The levels of 2,3-diphosphoglycerate (2,3-DPG), which affects the transport of oxygen by haemoglobin, were examined in horse blood. Resting levels of erythrocyte 2,3-DPG were established in thoroughbred horses, and levels of 2,3-DPG together with haemoglobin levels, were examined in a variety of conditions. A negative correlation was observed between erythrocyte 2,3-DPG and haemoglobin levels. Mares had higher erythrocyte 2,3-DPG levels was observed during training, and this variation may have a significant effect on haemoglobin oxygen transport. Erythrocyte 2,3-DPG levels were not affected by age or exercise.

Desickling of Sickle Cell Erythrocytes by Pulsed RF Fields.

Science.gov (United States)

1986-09-16

spectrophotometery. Field induced menbrane potential which causes the L partyl breakdown of the memrbrane and the formation of pores was calculated... plasma . Fig.5 shows the photographs of sickled and desickled SS erythrocytes which are suspended in Hank’s solution. As shown, desickled erythrocytes

Life cycle-dependent cytoskeletal modifications in Plasmodium falciparum infected erythrocytes.

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Hui Shi

Full Text Available Plasmodium falciparum infection of human erythrocytes is known to result in the modification of the host cell cytoskeleton by parasite-coded proteins. However, such modifications and corresponding implications in malaria pathogenesis have not been fully explored. Here, we probed the gradual modification of infected erythrocyte cytoskeleton with advancing stages of infection using atomic force microscopy (AFM. We reported a novel strategy to derive accurate and quantitative information on the knob structures and their connections with the spectrin network by performing AFM-based imaging analysis of the cytoplasmic surface of infected erythrocytes. Significant changes on the red cell cytoskeleton were observed from the expansion of spectrin network mesh size, extension of spectrin tetramers and the decrease of spectrin abundance with advancing stages of infection. The spectrin network appeared to aggregate around knobs but also appeared sparser at non-knob areas as the parasite matured. This dramatic modification of the erythrocyte skeleton during the advancing stage of malaria infection could contribute to the loss of deformability of the infected erythrocyte.

Life cycle-dependent cytoskeletal modifications in Plasmodium falciparum infected erythrocytes.

Science.gov (United States)

Shi, Hui; Liu, Zhuo; Li, Ang; Yin, Jing; Chong, Alvin G L; Tan, Kevin S W; Zhang, Yong; Lim, Chwee Teck

2013-01-01

Plasmodium falciparum infection of human erythrocytes is known to result in the modification of the host cell cytoskeleton by parasite-coded proteins. However, such modifications and corresponding implications in malaria pathogenesis have not been fully explored. Here, we probed the gradual modification of infected erythrocyte cytoskeleton with advancing stages of infection using atomic force microscopy (AFM). We reported a novel strategy to derive accurate and quantitative information on the knob structures and their connections with the spectrin network by performing AFM-based imaging analysis of the cytoplasmic surface of infected erythrocytes. Significant changes on the red cell cytoskeleton were observed from the expansion of spectrin network mesh size, extension of spectrin tetramers and the decrease of spectrin abundance with advancing stages of infection. The spectrin network appeared to aggregate around knobs but also appeared sparser at non-knob areas as the parasite matured. This dramatic modification of the erythrocyte skeleton during the advancing stage of malaria infection could contribute to the loss of deformability of the infected erythrocyte.

The role of the erythrocyte in antitumour drug transport

NARCIS (Netherlands)

Dumez, Herlinde

2005-01-01

The area of research on the substance-carrier capacity of the erythrocyte is rather limited and it remains difficult to estimate the impact of erythrocyte drug level monitoring in the clinic. Although equilibrium between blood and tissues based on the dissolution of compounds in the plasma water

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

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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.

Insulin radioreceptor assay on murine splenic leukocytes and peripheral erythrocytes

International Nuclear Information System (INIS)

Shimizu, F.; Kahn, R.

1982-01-01

Insulin radioreceptor assays were developed using splenic leukocytes and peripheral erythrocytes from individual mice. Splenic leukocytes were prepared using an NH 4 Cl buffer which did not alter insulin binding, but gave much higher yields than density gradient methods. Mouse erythrocytes were isolated from heparinized blood by three passages over a Boyum gradient, and a similar buffer was used to separate cells from free [ 125 I]iodoinsulin at the end of the binding incubation. Insulin binding to both splenic leukocytes and peripheral erythrocytes had typical pH, temperature, and time dependencies, and increased linearly with an increased number of cells. Optimal conditions for the splenic leukocytes (6 x 10 7 /ml) consisted of incubation with [ 125 I]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.0. In cells from 20 individual mice, the specific [ 125 I]iodoinsulin binding was 2.6 +/- 0.1% (SEM), and nonspecific binding was 0.3 +/- 0.04% (10.6% of total binding). Erythrocytes (2.8 x 10 9 /ml) were incubated with [ 125 ]iodoinsulin at 15 C for 2 h in Hepes buffer, pH 8.2. In cells from 25 individual mice, the specific [ 125 I]iodoinsulin binding was 4.5 +/- 0.2%, and nonspecific binding was 0.7 +/- 0.03% (13.6% of total binding). In both splenic leukocytes and peripheral erythrocytes, analysis of equilibrium binding data produced curvilinear Scatchard plots with approximately 3500 binding sites/leukocyte and 20 binding sites/erythrocyte. These data demonstrate that adequate numbers of splenic leukocytes and peripheral erythrocytes can be obtained from individual mice to study insulin binding in a precise and reproducible manner

Partial recovery of erythrocyte glycogen in diabetic rats treated with phenobarbital

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da-Silva C.A.

1997-01-01

Full Text Available Erythrocytes may play a role in glucose homeostasis during the postprandial period. Erythrocytes from diabetic patients are defective in glucose transport and metabolism, functions that may affect glycogen storage. Phenobarbital, a hepatic enzyme inducer, has been used in the treatment of patients with non-insulin-dependent diabetes mellitus (NIDDM, increasing the insulin-mediated glucose disposal. We studied the effects of phenobarbital treatment in vivo on glycemia and erythrocyte glycogen content in control and alloxan-diabetic rats during the postprandial period. In control rats (blood glucose, 73 to 111 mg/dl in femoral and suprahepatic veins the erythrocyte glycogen content was 45.4 ± 1.1 and 39.1 ± 0.8 µg/g Hb (mean ± SEM, N = 4-6 in the femoral artery and vein, respectively, and 37.9 ± 1.1 in the portal vein and 47.5 ± 0.9 in the suprahepatic vein. Diabetic rats (blood glucose, 300-350 mg/dl presented low (P<0.05 erythrocyte glycogen content, i.e., 9.6 ± 0.1 and 7.1 ± 0.7 µg/g Hb in the femoral artery and vein, respectively, and 10.0 ± 0.7 and 10.7 ± 0.5 in the portal and suprahepatic veins, respectively. After 10 days of treatment, phenobarbital (0.5 mg/ml in the drinking water did not change blood glucose or erythrocyte glycogen content in control rats. In diabetic rats, however, it lowered (P<0.05 blood glucose in the femoral artery (from 305 ± 18 to 204 ± 45 mg/dl and femoral vein (from 300 ± 11 to 174 ± 48 mg/dl and suprahepatic vein (from 350 ± 10 to 174 ± 42 mg/dl, but the reduction was not sufficient for complete recovery. Phenobarbital also stimulated the glycogen synthesis, leading to a partial recovery of glycogen stores in erythrocytes. In treated rats, erythrocyte glycogen content increased to 20.7 ± 3.8 µg/g Hb in the femoral artery and 30.9 ± 0.9 µg/g Hb in the suprahepatic vein (P<0.05. These data indicate that phenobarbital activated some of the insulin-stimulated glucose metabolism steps which were

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...... by the presence of apoM. The specific ability of apoM to promote export of S1P was independent of apoM being bound in HDL particles. Treatment with MK-571, an inhibitor of the ABCC1 transporter, effectively reduced export of S1P from human erythrocytes to apoM, whereas the export was unaffected by inhibitors...

Vitamin E supplementation protects erythrocyte membranes from oxidative stress in healthy Chinese middle-aged and elderly people.

Science.gov (United States)

Sun, Yongye; Ma, Aiguo; Li, Yong; Han, Xiuxia; Wang, Qiuzhen; Liang, Hui

2012-05-01

Elderly people are subject to higher levels of oxidative stress than are young people. Vitamin E, as a powerful antioxidant residing mainly in biomembranes, may provide effective protection against oxidative membrane damage and resultant age-related deterioration, especially in the elderly. We hypothesized that appropriate levels of vitamin E supplementation would protect erythrocyte membranes from oxidative stress and thus improve membrane fluidity in healthy middle-aged and elderly people. To test this, we conducted a 4-month double-blind, randomized trial in which 180 healthy subjects (55-70 years old) were randomly divided into 4 groups: group C (control), and 3 treatment groups in which daily doses of 100 mg (VE1), 200 mg (VE2), and 300 mg (VE3) dl-α-tocopheryl acetate were administered. We measured plasma α-tocopherol concentration, malondialdehyde, and superoxide dismutase levels, erythrocyte hemolysis, and erythrocyte membrane fluidity at the beginning and end of the trial. After 4 months supplementation, plasma α-tocopherol concentrations in the 3 treatment groups had increased by 71%, 78%, and 95%, respectively (all P stress in healthy middle-aged to elderly people, at least in part by improving erythrocyte membrane fluidity and reducing erythrocyte hemolysis. Copyright © 2012 Elsevier Inc. All rights reserved.

Sacha Inchi (Plukenetia volubilis L. powder: acute toxicity, 90 days oral toxicity study and micronucleus assay in rodents

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Idania Rodeiro

2018-02-01

Full Text Available Context: Sacha Inchi has been consumed for years by indigenous peoples. Meanwhile, its toxicological potential has not been sufficiently studied. Aims: To assess the acute, sub-chronic toxicity and genotoxicity evaluation of Sacha Inchi powder obtained from Plukenetia volubilis L. Methods: A dose of 2000 mg/kg was orally administered to rats and mice and toxicity symptoms for 14 days were observed. In repeated dose study, the product was orally administered to Sprague Dawley rats of both sexes. Animals received 50, 250 and 500 mg/kg/day of the product for 90 days. At the end, animals were sacrificed and samples were done for hematological and biochemical analysis, organ weighs and histopathological examination. Genotoxicity potential of Sacha Inchi powder was evaluated through micronucleus test in mice. Negative controls received the vehicle (carboxymethyl cellulose, 0.5% used. Results: No morbidity or mortality at 2000 mg/kg of the product were found. Sacha Inchi powder oral administration during 90 days to rats did not lead to death, body weight gain, food consumption, or adverse events. No significant changes on hematological or biochemical parameters, organ weights or histopathological findings were observed. Induction of micronucleus formation attributable to the product was not found in mice. Conclusions: No toxicity effects after oral acute exposure of Sacha Inchi power to rats and mice were observed. Neither toxicity attributable to oral doses of the product up to 500 mg/kg during 90 days to rats were found. Results suggested Sacha Inchi powder does not have genotoxicity potential under our experimental conditions.

The effects of polymeric plutonium on erythrocyte survival in mice, (1)

International Nuclear Information System (INIS)

Joshima, Hisamasa; Kashima, Masatoshi; Matsuoka, Osamu

1976-01-01

The changes in erythrocyte counts, hematocrit, hemoglobin, reticulocyte counts and erythrocyte survival following an intravenous injection of polymeric 239 Pu at the dose level of 15 μCi/kg, 10 μCi/kg and 5 μCi/kg were studied in CF no. 1 male mice in order to investigate the possible pathogenesis of anemia produced by irradiation of polymeric plutonium. The administration of 15 μCi/kg and 10 μCi/kg of polymeric plutonium produced anemia but 5 μCi/kg had no significant effect. Studies with 51 Cr labelled erythrocyte showed a moderate reduction in survival of erythrocyte following a single intraveneous injection of polymeric plutonium. Not only the intracorpuscular effect but also extracorpuscular effect of polymeric plutonium was considered to lead to a reduction in erythrocyte survival, but no clear dose relationship could be observed between the reduction of survival and either intracorpuscular effect or extracorpuscular effect. Although the most important pathogenesis of anemia produced by polymeric plutonium is supposed to be a decreased erythropoiesis, it was believed that both qualitatively impaired erythropoiesis and abnormal erythrocyte destruction might also play some role in the occurrence of anemia. (auth.)

Micronucleus formation compared to the survival rate of human melanoma cells after X-ray and neutron irradiation and hyperthermia

Energy Technology Data Exchange (ETDEWEB)

van Beuningen, D.; Streffer, C.; Bertholdt, G.

1981-09-01

After neutron and X-ray irradiation and combined X-ray irradiation and hyperthermia (3 hours, 42/sup 0/C), the survival rate of human melanoma cells was measured by means of the colony formation test and compared to the formation of micronuclei. Neutrons had a stronger effect on the formation of micronuclei than the combination of X-rays and hyperthermia. X-rays had the lowest effect. The dose effect curve showed a break at that dose level at which a reduction of cells was observed in the cultures. A good relation between survival rate and formation of micronuclei was found for the X-ray irradiation, but not for the neutron irradiation and the combined treatment. These observations are discussed. At least for X-rays, the micronucleus test has turned out to be a good screening method for the radiosensitivity of a biologic system.

Protective effects of several plant polyphenols against chromosomal damage induced in vivo by X-rays. Comparative study versus diosmin and rutin

Energy Technology Data Exchange (ETDEWEB)

Alcaraz, M; Rosa, B [Radiology and Physical Medicine Department of Furfural Espanol S.A., Murcia (Spain); Castillo, J; Benavente-Garcia, O; Lorente, J [Research and Development Department of Furfural Espanol S.A., Murcia (Spain); Vicente, V [Pathology Department of Furfural Espanol S.A., Murcia (Spain); Canteras, M [Biostatistical Department, Faculty of Medicine, University of Murcia, Murcia (Spain)

2001-03-01

Protective effects of grape (Vitis vinifera) seed (GSE), Citrus spp. fruits (CE) and olive (Olea europaea L.) leaf (OL) extracts, the flavonoids diosmin and rutin, widely used as pharmaceuticals, and dimethylsulphoxide (DMSO) against chromosomal damage induced by X-rays were determined by using the micronucleus test for anticlastogenic activity. The reduction of the frequency of micronucleated polychromatic erythrocytes (MnPCEs) in bone marrow of mouse exposed to X-rays was examined. The most effective compounds were, in order: GSE {approx} CE > rutin {approx} DMSO {approx} OL > diosmin. These results suggest a correlation between the antioxidant and anticlastogenic activity of these polyphenolic extracts. (author)

Protective effects of several plant polyphenols against chromosomal damage induced in vivo by X-rays. Comparative study versus diosmin and rutin

International Nuclear Information System (INIS)

Alcaraz, M.; Rosa, B.; Castillo, J.; Benavente-Garcia, O.; Lorente, J.; Vicente, V.; Canteras, M.

2001-01-01

Protective effects of grape (Vitis vinifera) seed (GSE), Citrus spp. fruits (CE) and olive (Olea europaea L.) leaf (OL) extracts, the flavonoids diosmin and rutin, widely used as pharmaceuticals, and dimethylsulphoxide (DMSO) against chromosomal damage induced by X-rays were determined by using the micronucleus test for anticlastogenic activity. The reduction of the frequency of micronucleated polychromatic erythrocytes (MnPCEs) in bone marrow of mouse exposed to X-rays was examined. The most effective compounds were, in order: GSE ∼ CE > rutin ∼ DMSO ∼ OL > diosmin. These results suggest a correlation between the antioxidant and anticlastogenic activity of these polyphenolic extracts. (author)

Stimulation of erythrocyte phosphatidylserine exposure by mercury ions

International Nuclear Information System (INIS)

Eisele, Kerstin; Lang, Philipp A.; Kempe, Daniela S.; Klarl, Barbara A.; Niemoeller, Olivier; Wieder, Thomas; Huber, Stephan M.; Duranton, Christophe; Lang, Florian

2006-01-01

The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg 2+ -induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg 2+ in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca 2+ -sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca 2+ activity and/or activate a sphingomyelinase leading to formation of ceramide. Ceramide sensitizes the scramblase to Ca 2+ . The present experiments explored the effect of Hg 2+ ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg 2+ (1 μM) indeed significantly increased annexin binding from 2.3 ± 0.5% (control condition) to 23 ± 6% (n = 6). This effect was paralleled by activation of a clotrimazole-sensitive K + -selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by ∼66% (n = 7) after challenge with mercury (1 μM). In conclusion, mercury ions activate a clotrimazole-sensitive K + -selective conductance leading to transient cell shrinkage. Moreover, Hg 2+ increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg 2+

No effect of human serum and erythrocytes enriched in n-3 fatty acids by oral intake on Plasmodium falciparum bloodstage parasites in vitro

DEFF Research Database (Denmark)

Abu-Zeid, Y.A.; Hansen, Harald S.; Jakobsen, P.H.

1993-01-01

-s) and pre-intake erythrocyte (pre-e). Also the effect of EPA and arachidonic acid (AA, 20:4n-6) on the erythrocytic growth of P. falciparum was tested using in vitro assays. The results show that both post-s and post-e had no antimalarial activity on P. falciparum. No differential antimalarial effect...... acid (EPA, 20:5n-3) of 3.5g/d and docosahexaenoic acid (DHA, 22:6n-3) of 2.5 g/d and 24 mg/d of total tocopherol. Post-intake fish oil serum (post-s) and erythrocytes (post-e) were tested in vitro for inhibitory activity against blood stages of P. falciparum compared with pre-intake serum (pre...

Red not dead: signaling in and from erythrocytes.

Science.gov (United States)

Sprague, Randy S; Stephenson, Alan H; Ellsworth, Mary L

2007-11-01

The oxygen required to meet metabolic needs of all tissues is delivered by the erythrocyte, a small, flexible cell which, in mammals, is devoid of a nucleus and mitochondria. Despite its simple appearance, this 'bag of hemoglobin' has an important role in its own distribution, enabling the delivery of oxygen to precisely meet localized metabolic need. When an erythrocyte enters an area in which tissue oxygen demand exceeds supply, a signaling pathway is activated resulting in the release of adenosine 5'-triphosphate (ATP). This ATP acts in a paracrine fashion to increase vascular caliber resulting in increased oxygen delivery. Defects in this pathway are found in erythrocytes of humans with type 2 diabetes (DM2) and could contribute to the perfusion abnormalities in skeletal muscle associated with this disease.

Carbohydrate metabolism in erythrocytes of copper deficient rats.

Science.gov (United States)

Brooks, S P J; Cockell, K A; Dawson, B A; Ratnayake, W M N; Lampi, B J; Belonje, B; Black, D B; Plouffe, L J

2003-11-01

Dietary copper deficiency is known to adversely affect the circulatory system of fructose-fed rats. Part of the problem may lie in the effect of copper deficiency on intermediary metabolism. To test this, weanling male Long-Evans rats were fed for 4 or 8 weeks on sucrose-based diets containing low or adequate copper content. Copper deficient rats had significantly lower plasma and tissue copper as well as lower plasma copper, zinc-superoxide dismutase activity. Copper deficient rats also had a significantly higher heart:body weight ratio when compared to pair-fed controls. Direct measurement of glycolysis and pentose phosphate pathway flux in erythrocytes using (13)C NMR showed no differences in carbon flux from glucose or fructose to pyruvate but a significantly higher flux through the lactate dehydrogenase locus in copper deficient rats (approximately 1.3 times, average of glucose and glucose + fructose measurements). Copper-deficient animals had significantly higher erythrocyte concentrations of glucose, fructose, glyceraldehyde 3-phosphate and NAD(+). Liver metabolite levels were also affected by copper deficiency being elevated in glycogen and fructose 1-phosphate content. The results show small changes in carbohydrate metabolism of copper deficient rats.

MODIFICATION OF ERYTHROCYTE MEMBRANE PROTEINS WITH POLYETHYLENE GLYCOL 1500

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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.

 Oxidative stress modulates the organization of erythrocyte membrane cytoskeleton

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Maria Olszewska

2012-07-01

Full Text Available  Background:Apart from their main role in transporting oxygen and carbon dioxide, erythrocytes play also an important role in organism antioxidative defence. Direct exposure to reactive oxygen species (ROS results in shortening of their half-life, even by 50�20The presence of glucose, being the substrate in pentose phosphate pathway (PPP cycle, is one of the factors that can have influence on the level of oxidative stress. The activity of PPP increases during oxidative stress. Glucose guarantees normal PPP functioning with the production of reductive equivalents in the amounts necessary to reproduction of glutathione – nonenzymatic free radical scavenger. In available literature there are no reports regarding the changes in protein contents of erythrocyte cytoskeleton exposed to t-butyl hydroperoxide in relation to glucose presence in incubation medium.Material/methods:Erythrocytes taken from 10 healthy subjects were used to assess the influence of generated free radicals on erythrocyte proteins and chosen parameters of oxidative stress. Erythrocytes were incubated in the solutions containing deferent concentrations of t-butyl hydroperoxide and glucose. Electrophoresis was performed on polyacrylamide gel in denaturating conditions. The contents of tryptophan in membranes was evaluated spectrofluorometrically.Results/conclusions:In vitro conditions oxidative stress leads to protein damage in erythrocyte cytoskeleton, both in proteins inside the cell as well as having contact with extracellular environment. In consequence, the amount of low-molecular proteins – mainly globin, which bind to cytoskeleton, increases. This process takes place independently of glucose presence in incubation medium. One of the element of protein cytoskeleton, tryptophan, also undergoes degradation. The decrease of its contents is higher during erythrocyte exposure to t-BOOH in environment containing glucose, what can suggest prooxidative influence of glucose in

Platelet inhibition by nitrite is dependent on erythrocytes and deoxygenation.

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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.

Stimulation of Suicidal Erythrocyte Death by the Antimalarial Drug Mefloquine

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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.

Inhibitory effects of Enteromorpha linza polysaccharide on micronucleus of Allium sativum root cells.

Science.gov (United States)

Zhang, Zhongshan; Wang, Xiaomei; Li, Jingfen; Liu, Chongbin; Zhang, Quanbin

2016-06-01

In this study, the antimutagenic function of the polysaccharide from Enteromorpha linza with the micronucleus test of Allium sativum root cells induced by sulfur dioxide and ultraviolet was studied. The concentration-effect relation of the two inducers was firstly evaluated. The results showed that an increase of genotoxicity damage was demonstrated and micronuclei frequency induced by sulfur dioxide and ultraviolet displayed dose dependent increases. All the doses of polysaccharide did affect the micronuclei frequency formation compared with the negative control. And also, the significant increase in inhibition rate of micronuclei frequency was observed with the increase of the dose of polysaccharide. It was showed maximum inhibition of micronuclei frequency cells (71.74% and 66.70%) at a concentration of 200g/mL in three experiments. The low molecular weight polysaccharide showed higher inhibition rate than raw polysaccharide at the higher concentration (50g/mL) in the absence of sulfur dioxide and ultraviolet. It was confirmed to be a good mutant inhibitor. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

Estudo fitoquímico e análise mutagênica das folhas e inflorescências de Erythrina mulungu (Mart. ex Benth. através do teste de micronúcleo em roedores Phytochemical and mutagenic analysis of leaves and inflorescences of Erythrina mulungu (Mart. Ex Benth through micronucleus test in rodents

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A.P De Bona

2012-01-01

Full Text Available Este trabalho teve como objetivo investigar a composição química, estabelecer a dose letal média (DL50 e avaliar os potenciais efeitos mutagênicos do extrato hidroalcoólico de folhas e inflorescências de Erythrina mulungu Mart. ex Benth por meio do teste de micronúcleo em medula óssea de camundongos. Os ensaios fitoquímicos foram realizados através de reações preliminares com mudança de coloração e/ou formação de precipitado; a DL50, por meio da administração intraperitoneal de três concentrações dos extratos, avaliando-se o número de óbitos após 48 horas e o teste de micronúcleo foi feito por meio do método do esfregaço, após exposição dos animais a cinco dias de tratamento. Os resultados fitoquímicos demonstraram presença de açúcares redutores, fenóis e taninos, proteínas e aminoácidos, flavonóides, alcalóides, depsídeos e depsidonas e derivados de cumarina em ambos os órgãos; saponinas espumídicas e esteróides e triterpenóides nas folhas e glicosídeos cardiotônicos e antraquinônicos e alcalóides nas inflorescências. Para a DL50 a folha demonstrou-se atóxica e a inflorescência moderadamente tóxica. Para o teste de micronúcleo, os resultados indicaram ausência de citotoxicidade e genotoxicidade dose-dependente para as folhas e independente da dose para as inflorescências. Assim, esses resultados sugerem que a planta, nas condições analisadas, possui potencial para induzir danos ao DNA.This study aimed to investigate the chemical composition, to establish the mean lethal dose (LD50 and to assess the potential mutagenic effects of hydroalcoholic extract of leaves and inflorescences of Erythrina mulungu Mart. ex Benth by using micronucleus test in bone marrow of mice. Phytochemical assays were carried out through preliminary reactions with color change and/or precipitate formation; the LD50 was obtained by intraperitoneal administration of three concentrations of the extracts, assessing

Dose response curve for micronucleus of cytokinesis-block method in human lymphocytes after 60Co-gamma ray exposure

International Nuclear Information System (INIS)

Gao Jinsheng; Zheng Siying; Cai Feng

1993-08-01

The micronucleus technique of cytokines block has been proposed as a new method to measure chromosome damage in cytogenetic. The cytokines is blocked by using cytochalasin B (Cyt-B), and micronuclei are scored in cytokines-blocked (CB) cells. This can easily be done owing to the appearance of binucleate cells and large numbers accumulated by adding 3.0 μg/ml cytochalasin B at 44 hours and scoring at 72 hours. The results show that the optimum concentration of Cyt-B is 3.0 μg/ml. the Cyt-B itself can not induce the increase of micronuclei. The micronucleus frequency of normal individuals in vivo, there is an approximately linear relationship between the frequency of induced micronuclei and irradiation dose. The formula is Y 0.36 D + 2.74 (γ 2 = 0.995 P<0.01). Because the cytokines block method is simple and reliable, it is effective for assaying chromosome damage caused by genetic toxic materials

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.

Erythrocyte antioxidant protection of rose hips (Rosa spp.).

Science.gov (United States)

Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

2012-01-01

Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

Inclusion bodies in loggerhead erythrocytes are associated with unstable hemoglobin and resemble human Heinz bodies.

Science.gov (United States)

Basile, Filomena; Di Santi, Annalisa; Caldora, Mercedes; Ferretti, Luigi; Bentivegna, Flegra; Pica, Alessandra

2011-08-01

The aim of this study was to clarify the role of the erythrocyte inclusions found during the hematological screening of loggerhead population of the Mediterranean Sea. We studied the erythrocyte inclusions in blood specimens collected from six juvenile and nine adult specimens of the loggerhead turtle, Caretta caretta, from the Adriatic and Tyrrhenian Seas. Our study indicates that the percentage of mature erythrocytes containing inclusions ranged from 3 to 82%. Each erythrocyte contained only one round inclusion body. Inclusion bodies stained with May Grünwald-Giemsa show that their cytochemical and ultrastructure characteristics are identical to those of human Heinz bodies. Because Heinz bodies originate from the precipitation of unstable hemoglobin (Hb) and cause globular osmotic resistance to increase, we analyzed loggerhead Hb using electrophoresis and high-performance liquid chromatography to detect and quantitate Hb fractions. We also tested the resistance of Hb to alkaline pH, heat, isopropanol denaturation, and globular osmosis. Our hemogram results excluded the occurrence of any infection, which could be associated with an inclusion body, in all the specimens. Negative Feulgen staining indicated that the inclusion bodies are not derived from DNA fragmentation. We hypothesize that amino acid substitutions could explain why loggerhead Hb precipitates under normal physiologic conditions, forming Heinz bodies. The identification of inclusion bodies in loggerhead erythrocytes allow us to better understand the haematological characteristics and the physiology of these ancient reptiles, thus aiding efforts to conserve such an endangered species. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

No effect of human serum and erythrocytes enriched in n-3 fatty acids by oral intake on Plasmodium falciparum blood stage parasites in vitro

DEFF Research Database (Denmark)

Abu-Zeid, Y A; Hansen, H S; Jakobsen, P H

1993-01-01

-s) and pre-intake erythrocyte (pre-e). Also the effect of EPA and arachidonic acid (AA, 20:4n-6) on the erythrocytic growth of P. falciparum was tested using in vitro assays. The results show that both post-s and post-e had no antimalarial activity on P. falciparum. No differential antimalarial effect...... acid (EPA, 20:5n-3) of 3.5 g/d and docosahexaenoic acid (DHA, 22:6n-3) of 2.5 g/d and 24 mg/d of total tocopherol. Post-intake fish oil serum (post-s) and erythrocytes (post-e) were tested in vitro for inhibitory activity against blood stages of P. falciparum compared with pre-intake serum (pre...

78 FR 66700 - Toxic Substances Control Act Chemical Testing; Receipt of Test Data

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2013-11-06

... additive for food Rat--Up-and-Down processing, and as Procedure. ingredient in aluminum Micronucleus Test... Toxicity to Fish; Acute Toxicity to Daphnia; Toxicity to Algae; Acute Toxicity to Mammals; Bacterial..., cold Study in Zebra Fish set, and sheet-fed (Brachydanio rerio). applications. Acute Toxicity Study in...

Hemolitic action of Naja naja atra cardiotoxin on erythrocytes from different animals

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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.

Spray drying for preservation of erythrocytes: effect of atomization on hemolysis.

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McLean, Mary; Han, Xiao-Yue; Higgins, Adam Z

2013-04-01

Spray drying has the potential to enable storage of erythrocytes at room temperature in the dry state. The spray drying process involves atomization of a liquid into small droplets and drying of the droplets in a gas stream. In this short report, we focus on the atomization process. To decouple atomization from drying, erythrocyte suspensions were sprayed with a two-fluid atomizer nozzle using humid nitrogen as the atomizing gas. The median droplet size was less than 100 μm for all of the spray conditions investigated, indicating that the suspensions were successfully atomized. Hemolysis was significantly affected by the hematocrit of the erythrocyte suspension, the suspension flow rate, and the atomizing gas flow rate (pspray drying may be a feasible option for erythrocyte biopreservation.

In Vitro and In Vivo Genotoxicity Assessment of Aristolochia manshuriensis Kom.

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Youn-Hwan Hwang

2012-01-01

Full Text Available Arisolochiae species plants containing aristolochic acids I and II (AA I and AA II are well known to cause aristolochic acid nephropathy (AAN. Recently, there are various approaches to use AAs-containing herbs after the removal of their toxic factors. However, there is little information about genotoxicity of Arisolochiae manshuriensis Kom. (AMK per se. To obtain safety information for AMK, its genotoxicity was evaluated in accordance with OECD guideline. To evaluate genotoxicity of AMK, we tested bacterial reverse mutation assay, chromosomal aberration test, and micronucleus test. Here, we also determined the amounts of AA I and II in AMK (2.85 ± 0.08 and 0.50 ± 0.02 mg/g extract, resp.. In bacterial reverse mutation assay, AMK dose-dependently increased revertant colony numbers in TA98, TA100 and TA1537 regardless of metabolic activation. AMK increased the incidence of chromosomal aberration in Chinese hamster ovary-K1 cells, but there was no statistically significant difference. The incidences of micronucleus in bone marrow erythrocyte were significantly increased in mice after oral administration of AMK (5000 mg/kg, comparing with those of vehicle group (P<0.05. The results of three standard tests suggest that the genotoxicity of AMK is directly related to the AAs contents in AMK.

Lack of genotoxic effect of food dyes amaranth, sunset yellow and tartrazine and their metabolites in the gut micronucleus assay in mice.

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Poul, Martine; Jarry, Gérard; Elhkim, Mostafa Ould; Poul, Jean-Michel

2009-02-01

The food dyes amaranth, sunset yellow and tartrazine were administered twice, at 24h intervals, by oral gavage to mice and assessed in the in vivo gut micronucleus test for genotoxic effects (frequency of micronucleated cells) and toxicity (apoptotic and mitotic cells). The concentrations of each compound and their main metabolites (sulfanilic acid and naphthionic acid) were measured in faeces during a 24-h period after single oral administrations of the food dyes to mice. Parent dye compounds and their main aromatic amine metabolites were detected in significant amounts in the environment of colonic cells. Acute oral exposure to food dye additives amaranth, sunset yellow and tartrazine did not induce genotoxic effect in the micronucleus gut assay in mice at doses up to 2000 mg/kg b.w. Food dyes administration increased the mitotic cells at all dose levels when compared to controls. These results suggest that the transient DNA damages previously observed in the colon of mice treated by amaranth and tartrazine by the in vivo comet assay [Sasaki, Y.F., Kawaguchi, S., Kamaya, A., Ohshita, M., Kabasawa, K., Iwama, K., Taniguchi, K., Tsuda, S., 2002. The comet assay with 8 mouse organs: results with 39 currently used food additives. Mutat. Res. 519, 103-119] are unable to be fixed in stable genotoxic lesions and might be partly explained by local cytotoxicity of the dyes.

3-Nitrobenzanthrone (3-NBA) induced micronucleus formation and DNA damage in human hepatoma (HepG2) cells.

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Lamy, Evelyn; Kassie, Fekadu; Gminski, Richard; Schmeiser, Heinz H; Mersch-Sundermann, Volker

2004-01-15

3-Nitrobenzanthrone (3-NBA), identified in diesel exhaust and in airborne particulate matter, is a potent mutagen in Salmonella, induces micronuclei formation in mice and in human cells and DNA adducts in rats. In the present study, we investigated the genotoxic potency of 3-NBA in human HepG2 cells using the micronucleus (MN) assay and the single cell gel electrophoresis (SCGE). 3-NBA caused a genotoxic effect at concentrations > or =12 nM in both assays. In the micronucleus assay, we found 98.7+/-10.3 MN/1000 BNC at a concentration of 100 nM 3-NBA in comparison to 27.3+/-0.6 MN/1000 BNC with the negative control. At the same concentration, the DNA-migration (SCGE) showed an Olive tail moment (OTM) of 2.7+/-0.45 and %DNA in the tail of 8.28+/-0.76; OTM and %DNA in the tail of cells treated with the negative control were 0.73+/-0.08 and 2.81+/-0.30, respectively. The results are discussed under consideration of former studies.

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

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

2015-01-01

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

Radioprotection on nucleated and anucleated erythrocytes by oxide-reduction coenzymes

International Nuclear Information System (INIS)

Fernandez, M.; Tomicic, I.; Rojo, I.

1981-01-01

The protective effects of NAD, FAD and quinone and mixtures of these compounds were studied on gamma irradiated rabbit and chicken erythrocytes. The dose relative factor (DRF 37) was evaluated by visible absorbancy measurements of liberated hemoglobin. The DRF 37 obtained on rabbit erythrocytes were: NAD+FAD+quinone mixture: 11,1; NAD+ quinone mixture: 6,1; FAD+quinone mixture: 6,1; NAD: 1,6; FAD: 5,5; quinone: 5,1. The DRF 37 obtained with the mixture NAD+FAD+quinone on chicken erythrocytes was 3,9. The high efficiency of the radioprotective mixture NAD+FAD+ quinone is discussed. (author)

Clotrimazole enhances lysis of human erythrocytes induced by t-BHP.

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Lisovskaya, Irene L; Shcherbachenko, Irina M; Volkova, Rimma I; Ataullakhanov, Fazoil I

2009-08-14

Clotrimazole (CLT) is an antifungal and antimalarial agent also effective as a Gardos channel inhibitor. In addition, CLT possesses antitumor properties. Recent data provide evidence that CLT forms a complex with heme (hemin), which produces a more potent lytic effect than heme alone. This study addressed the effect of CLT on the lysis of normal human erythrocytes induced by tert-butyl hydroperoxide (t-BHP). For the first time, it was shown that 10 microM CLT significantly enhanced the lytic effect of t-BHP on erythrocytes in both Ca(2+)-containing and Ca(2+)-free media, suggesting that the effect is not related to Gardos channels. CLT did not affect the rate of free radical generation, the kinetics of GSH degradation, methemoglobin formation and TBARS generation; therefore, we concluded that CLT does not cause additional oxidative damage to erythrocytes treated with t-BHP. It is tempted to speculate that CLT enhances t-BHP-induced changes in erythrocyte volume and lysis largely by forming a complex with hemin released during hemoglobin oxidation in erythrocytes: the CLT-hemin complex destabilizes the cell membrane more potently than hemin alone. If so, the effect of CLT on cell membrane damage during free-radical oxidation may be used to increase the efficacy of antitumor therapy.

Bio-monitoring for the genotoxic assessment in road construction workers as determined by the buccal micronucleus cytome assay.

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Çelik, Ayla; Yildirim, Seda; Ekinci, Seda Yaprak; Taşdelen, Bahar

2013-06-01

Buccal micronucleus cytome (BMCyt) assay monitors genetic damage, cell proliferation and cell death in humans exposed to occupational and environmental agents. BMCyt is used as an indicator of genotoxic exposure, since it is associated with chromosomal instability. There is little research on the occupational exposure among road construction workers for genotoxicity testing. In the present study, we evaluated MN frequencies and other nuclear changes, karyorrhexis (KR), karyolysis (KL), broken egg (BE), binucleate (BN), condensed chromatin cell (CCC), and picnotic cell (PC) in buccal mucosa cells of 40 road construction workers (twenty smokers and twenty non-smokers) and 40 control groups consisting of healthy persons (twenty smokers and twenty non-smokers). Microscopic observation was performed of 2000 cells per individual in both road construction workers and control group. In control and worker groups, for each person repair index (RI) was calculated via formula KR+L/BE+MN. The results showed a statistically significant increase in the frequency of MN in buccal epithelial cells of exposed group compared with control group (proad construction workers, RI is lower than the control group. There is a significant difference between workers and control group (proad paving operations are absorbed by workers and that asphalt fume exposure is able to significantly induce cytogenetic damage in buccal mucosa cells of workers after controlling some possible confounding factors, such as age, sex and smoking habits. In addition to determination of nuclear changes and the micronucleus, the determination of RI value presents a new approach to genotoxic bio-monitoring assessment studies of occupationally exposed population. Copyright © 2013 Elsevier Inc. All rights reserved.

Does the chocolate interfere with the radiolabelling of erythrocytes with 99 mTc?; Le chocolat interfere-t-il avec le radiomarquage des erythrocytes au 99 mTc?

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Bustani, H.; Colavolpe, C.; Imbert-Joscht, I.; Moubarik, C.; Havlik, P.; Pisano, P.; Guillet, B. [Service de medecine nucleaire, CHU Nord, Marseille, (France)

2009-05-15

We present in this work the case of a failure of erythrocytes labelling with {sup 99m}Tc for a twenty five years old patient making the examination not interpretable. The patient reported that she drank a chocolate drink the morning before the examination. it is the first observation of a such interaction between the chocolate consumption. We do not have any explanation at this date, some compounds in the cocoa can be considered with caution. Some flavonoids (catechins and pro-cyanidins) modify the plasmatic and intra-erythrocyte oxido-reducer statute and could interact with the labelling (specific reduction of the {sup 99m}Tc pertechnetate in the middle of erythrocyte by the tin pyrophosphate. These compounds, as well as the methyl-xanthine-theobromine, seem modify the membrane permeability of erythrocytes and could interfere with the input of pyrophosphate or {sup 99m}Tc-pertechnetate in the middle of erythrocyte. these observations, in spite of preliminary ones, lead us to recommend near the patients to avoid the chocolate foods in the twenty four hours before this type of examinations. (N.C.)

Seahorse (Hippocampus reidi) as a bioindicator of crude oil exposure.

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Delunardo, Frederico Augusto Cariello; de Carvalho, Luciano Rodrigues; da Silva, Bruno Ferreira; Galão, Michel; Val, Adalberto Luís; Chippari-Gomes, Adriana R

2015-07-01

This study explored the suitability of the seahorse Hippocampus reidi (Ginsburg, 1933) for assessing biomarkers of genotoxic effects and its use as a sentinel organism to detect the effects of acute exposure to petroleum hydrocarbons. Fish were exposed to three concentrations of crude oil (10, 20 and 30 g/kg) for 96 h, and the activity of phase II biotransformation enzyme glutathione S-transferase (GST) was measured. In addition, we performed genotoxicity assays, such as comet assay, micronucleus (MN) test and nuclear abnormalities (NA) induction, on the erythrocytes of the fish species. Our results revealed that the inhibition of hepatic GST activity in H. reidi was dependent on increasing crude oil concentrations. In contrast, an increase in the damage index (DI) and MN frequency were observed with increased crude oil concentrations. These results indicate that the alkaline comet assay and micronucleus test were suitable and useful in the evaluation of the genotoxicity of crude oil, which could improve determinations of the impact of oil spills on fish populations. In addition, H. reidi is a promising "sentinel organism" to detect the genotoxic impact of petroleum hydrocarbons. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of the Genotoxic and Antigenotoxic Effects of Andiroba (Carapa guianensis Aublet Oil and Nanoemulsion on Swiss Mice

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Karina Motta Melo

2018-01-01

Full Text Available The Carapa guianensis (andiroba oil is commonly used by the Amazon population for medicinal purposes. The objective of this study was to determine the genotoxic and antigenotoxic potential of the andiroba oil (AO and nanoemulsion (AN using Swiss mice. Therefore, we used the comet assay and micronucleus test. The AO predominant compounds were oleic (39.13%, palmitic (33.22%, and linoleic (16.86% acids. AN composition obeyed the surfactant/oil ratio of 0.69, and the Tween 80/Span 80 ratio was held at 0.9. Our results showed no cytotoxicity or genotoxicity in the mice treated with AO and AN alone. However, there was a significant reduction in the polychromatic erythrocytes (PCEs numbers in all groups treated with doxorubicin (DOX, including those pretreated with AO and AN. Thus, the samples tested did not protect against DOX. On the other hand, our results showed a large increase in micronucleus (MN formation when the mice were treated with DOX alone; these numbers were reduced when the animals were pretreated with AO and AN. The results indicate a protective effect of andiroba on MN formation and show no evidence of genotoxicity in mice.

Targeted disruption of py235ebp-1: Invasion of erythrocytes by Plasmodium yoelii using an alternative py235 erythrocyte binding protein

KAUST Repository

Ogun, Solabomi A.

2011-02-17

Plasmodium yoelii YM asexual blood stage parasites express multiple members of the py235 gene family, part of the super-family of genes including those coding for Plasmodium vivax reticulocyte binding proteins and Plasmodium falciparum RH proteins. We previously identified a Py235 erythrocyte binding protein (Py235EBP-1, encoded by the PY01365 gene) that is recognized by protective mAb 25.77. Proteins recognized by a second protective mAb 25.37 have been identified by mass spectrometry and are encoded by two genes, PY01185 and PY05995/PY03534. We deleted the PY01365 gene and examined the phenotype. The expression of the members of the py235 family in both the WT and gene deletion parasites was measured by quantitative RT-PCR and RNA-Seq. py235ebp-1 expression was undetectable in the knockout parasite, but transcription of other members of the family was essentially unaffected. The knockout parasites continued to react with mAb 25.77; and the 25.77-binding proteins in these parasites were the PY01185 and PY05995/PY03534 products. The PY01185 product was also identified as erythrocyte binding. There was no clear change in erythrocyte invasion profile suggesting that the PY01185 gene product (designated PY235EBP-2) is able to fulfill the role of EBP-1 by serving as an invasion ligand although the molecular details of its interaction with erythrocytes have not been examined. The PY01365, PY01185, and PY05995/PY03534 genes are part of a distinct subset of the py235 family. In P. falciparum, the RH protein genes are under epigenetic control and expression correlates with binding to distinct erythrocyte receptors and specific invasion pathways, whereas in P. yoelii YM all the genes are expressed and deletion of one does not result in upregulation of another. We propose that simultaneous expression of multiple Py235 ligands enables invasion of a wide range of host erythrocytes even in the presence of antibodies to one or more of the proteins and that this functional

Targeted disruption of py235ebp-1: Invasion of erythrocytes by Plasmodium yoelii using an alternative py235 erythrocyte binding protein

KAUST Repository

Ogun, Solabomi A.; Tewari, Rita; Otto, Thomas D.; Howell, Steven A.; Knuepfer, Ellen; Cunningham, Deirdre A.; Xu, Zhengyao; Pain, Arnab; Holder, Anthony A.

2011-01-01

Plasmodium yoelii YM asexual blood stage parasites express multiple members of the py235 gene family, part of the super-family of genes including those coding for Plasmodium vivax reticulocyte binding proteins and Plasmodium falciparum RH proteins. We previously identified a Py235 erythrocyte binding protein (Py235EBP-1, encoded by the PY01365 gene) that is recognized by protective mAb 25.77. Proteins recognized by a second protective mAb 25.37 have been identified by mass spectrometry and are encoded by two genes, PY01185 and PY05995/PY03534. We deleted the PY01365 gene and examined the phenotype. The expression of the members of the py235 family in both the WT and gene deletion parasites was measured by quantitative RT-PCR and RNA-Seq. py235ebp-1 expression was undetectable in the knockout parasite, but transcription of other members of the family was essentially unaffected. The knockout parasites continued to react with mAb 25.77; and the 25.77-binding proteins in these parasites were the PY01185 and PY05995/PY03534 products. The PY01185 product was also identified as erythrocyte binding. There was no clear change in erythrocyte invasion profile suggesting that the PY01185 gene product (designated PY235EBP-2) is able to fulfill the role of EBP-1 by serving as an invasion ligand although the molecular details of its interaction with erythrocytes have not been examined. The PY01365, PY01185, and PY05995/PY03534 genes are part of a distinct subset of the py235 family. In P. falciparum, the RH protein genes are under epigenetic control and expression correlates with binding to distinct erythrocyte receptors and specific invasion pathways, whereas in P. yoelii YM all the genes are expressed and deletion of one does not result in upregulation of another. We propose that simultaneous expression of multiple Py235 ligands enables invasion of a wide range of host erythrocytes even in the presence of antibodies to one or more of the proteins and that this functional

Targeted disruption of py235ebp-1: invasion of erythrocytes by Plasmodium yoelii using an alternative Py235 erythrocyte binding protein.

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Solabomi A Ogun

2011-02-01

Full Text Available Plasmodium yoelii YM asexual blood stage parasites express multiple members of the py235 gene family, part of the super-family of genes including those coding for Plasmodium vivax reticulocyte binding proteins and Plasmodium falciparum RH proteins. We previously identified a Py235 erythrocyte binding protein (Py235EBP-1, encoded by the PY01365 gene that is recognized by protective mAb 25.77. Proteins recognized by a second protective mAb 25.37 have been identified by mass spectrometry and are encoded by two genes, PY01185 and PY05995/PY03534. We deleted the PY01365 gene and examined the phenotype. The expression of the members of the py235 family in both the WT and gene deletion parasites was measured by quantitative RT-PCR and RNA-Seq. py235ebp-1 expression was undetectable in the knockout parasite, but transcription of other members of the family was essentially unaffected. The knockout parasites continued to react with mAb 25.77; and the 25.77-binding proteins in these parasites were the PY01185 and PY05995/PY03534 products. The PY01185 product was also identified as erythrocyte binding. There was no clear change in erythrocyte invasion profile suggesting that the PY01185 gene product (designated PY235EBP-2 is able to fulfill the role of EBP-1 by serving as an invasion ligand although the molecular details of its interaction with erythrocytes have not been examined. The PY01365, PY01185, and PY05995/PY03534 genes are part of a distinct subset of the py235 family. In P. falciparum, the RH protein genes are under epigenetic control and expression correlates with binding to distinct erythrocyte receptors and specific invasion pathways, whereas in P. yoelii YM all the genes are expressed and deletion of one does not result in upregulation of another. We propose that simultaneous expression of multiple Py235 ligands enables invasion of a wide range of host erythrocytes even in the presence of antibodies to one or more of the proteins and that this

Diet-induced obesity increases the frequency of Pig-a mutant erythrocytes in male C57BL/6J mice.

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Wickliffe, Jeffrey K; Dertinger, Stephen D; Torous, Dorothea K; Avlasevich, Svetlana L; Simon-Friedt, Bridget R; Wilson, Mark J

2016-12-01

Obesity increases the risk of a number of chronic diseases in humans including several cancers. Biological mechanisms responsible for such increased risks are not well understood at present. Increases in systemic inflammation and oxidative stress, endogenous production of mutagenic metabolites, altered signaling in proliferative pathways, and increased sensitivity to exogenous mutagens and carcinogens are some of the potential contributing factors. We hypothesize that obesity creates an endogenously mutagenic environment in addition to increasing the sensitivity to environmental mutagens. To test this hypothesis, we examined two in vivo genotoxicity endpoints. Pig-a mutant frequencies and micronucleus frequencies were determined in blood cells in two independent experiments in 30-week old male mice reared on either a high-fat diet (60% calories from fat) that exhibit an obese phenotype or a normal-fat diet (10% calories from fat) that do not exhibit an obese phenotype. Mice were assayed again at 52 weeks of age in one of the experiments. N-ethyl-N-nitrosourea (ENU) was used as a positive mutation control in one experiment. ENU induced a robust Pig-a mutant and micronucleus response in both phenotypes. Obese, otherwise untreated mice, did not differ from non-obese mice with respect to Pig-a mutant frequencies in reticulocytes or micronucleus frequencies. However, such mice, had significantly higher and sustained Pig-a mutant frequencies (increased 2.5-3.7-fold, p obese mice (based on measurements collected at 30 weeks or 30 and 52 weeks of age). This suggests that obesity, in the absence of exposure to an exogenous mutagen, is itself mutagenic. Environ. Mol. Mutagen. 57:668-677, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

In vivo survival of [14C]sucrose-loaded porcine carrier erythrocytes

International Nuclear Information System (INIS)

DeLoach, J.R.

1983-01-01

Porcine carrier erythrocyte survival was measured in adult pigs. [14C]Sucrose-loaded erythrocytes had a biphasic survival curve, with as much as 50% of the cells removed from circulation in the first 24 hours. The remaining cells had a 35-day half-life. Encapsulation values were measured for porcine erythrocytes and entrapment of [14C]sucrose was greater than 45%. Addition of inosine and glucose to the dialyzed cells and to the final wash buffer before reinjection of autologous cells did not improve their survival

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

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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.

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

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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.

The knocked-out erythrocyte sedimentation rate: periodontal abscess.

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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.

51Cr - erythrocyte survival curves

International Nuclear Information System (INIS)

Paiva Costa, J. de.

1982-07-01

Sixteen patients were studied, being fifteen patients in hemolytic state, and a normal individual as a witness. The aim was to obtain better techniques for the analysis of the erythrocytes, survival curves, according to the recommendations of the International Committee of Hematology. It was used the radiochromatic method as a tracer. Previously a revisional study of the International Literature was made in its aspects inherent to the work in execution, rendering possible to establish comparisons and clarify phonomena observed in cur investigation. Several parameters were considered in this study, hindering both the exponential and the linear curves. The analysis of the survival curves of the erythrocytes in the studied group, revealed that the elution factor did not present a homogeneous answer quantitatively to all, though, the result of the analysis of these curves have been established, through listed programs in the electronic calculator. (Author) [pt

Graphistrength© C100 MultiWalled Carbon Nanotubes (MWCNT): thirteen-week inhalation toxicity study in rats with 13- and 52-week recovery periods combined with comet and micronucleus assays

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Régnier, Jean-François; Pothmann-Krings, Daniela; Simar, Sophie; Dony, Eva; Le Net, Jean-Loïc; Beausoleil, Julien

2017-06-01

Graphistrength© C100 provides superior electrical and mechanical properties for various applications and is one of the industrial MWCNT referenced in the OECD sponsorship program for the safety testing of nanomaterials. Graphistrength© C100 is formed of MWCNT (ca. 12 walls, outer mean diameter ca. 12 nm, length ca. 1 µm) agglomerated in particles with a granulometry centered on 400 µm. A general feature of MWCNT after inhalation or intratracheal exposures is the induction of an inflammatory reaction in the lungs sometimes associated with local genotoxic effects. Most of the in vitro and in vivo genotoxicity data available on Graphistrength© C100 are negative. However, a weak DNA damage activity in the in vitro and in vivo FPG-modified Comet assays and a weak clastogenic effect in the in vitro micronucleus test were reported. After investigating different parameters for the aerosol generation, male and female Wistar rats were exposed by nose-only inhalation (6h/day, 5d/week) to target concentrations of 0.05, 0.25 and 5.0 mg/m3 air of a respirable aerosol (MMAD males and females were evaluated by the micronucleus test (OECD TG 474) and DNA damage in the lung, kidney and liver cells of males were assessed by both the standard and the human 8-oxoguanine DNA N-glycosylase 1 (hOGG1)-modified comet assay (OECD TG 489). Concentration-related deposition of black particles (MWCNT) was observed in lungs. At all sacrifice periods, an inflammatory lung reaction was observed in rats exposed to 5.0 mg/m3 associated with changes in the differential white blood cells counts. The lung inflammation was characterized by changes in the cytological, biochemical and cytokine parameters of the BALF, an increase of the lung weight, an interstitial inflammation mainly around the alveolar ducts at the bronchiole-alveolar junction and a cell hypertrophy/hyperplasia in the terminal and respiratory bronchioles. The slight changes in BALF parameters observed at 0.25 mg/m3 recovered after

Evaluation of genetic toxicity of 6-diazo-5-oxo-l-norleucine (DON).

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Kulkarni, Rohan M; Dakoulas, Emily W; Miller, Ken E; Terse, Pramod S

2017-09-01

DON (6-diazo-5-oxo-l-norleucine), a glutamine antagonist, was demonstrated to exhibit analgesic, antibacterial, antiviral and anticancer properties. The study was performed to characterize its in vitro and in vivo genetic toxicity potential. DON was tested in the bacterial reverse mutation assay (Ames test) using Salmonella typhimurium tester strains (TA98, TA100, TA1535 and TA1537) and Escherichia coli tester strain (WP2 uvrA) with and without S9 and also with reductive S9. In addition, DON was tested for the chromosome aberrations in Chinese hamster ovary (CHO) cells with or without S9 to evaluate the clastogenic potential. Furthermore, DON was also evaluated for its in vivo clastogenic activity by detecting micronuclei in polychromatic erythrocyte (PCE) cells in bone marrow collected from the male mice dosed intravenously with 500, 100, 10, 1 and 0.1 mg/kg at 24 and 48-h post-dose. The Ames mutagenicity assay showed no positive mutagenic responses. However, the in vitro chromosome aberration assay demonstrated dose dependent statistically positive increase in structural aberrations at 4 and 20-h exposure without S9 and also at 4-h exposure with S9. The in vivo micronucleus assay also revealed a statistically positive response for micronucleus formation at 500, 100 and 10 mg/kg at 24 and 48-h post-dose. Thus, DON appears to be negative in the Ames test but positive in the in vitro chromosome aberration assay and in the in vivo micronucleus assay. In conclusion, the results indicate DON is a genotoxic compound with a plausible epigenetic mechanism.

Erythrocytic Adenosine Monophosphate as an Alternative Purine Source in Plasmodium falciparum*

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Cassera, María B.; Hazleton, Keith Z.; Riegelhaupt, Paul M.; Merino, Emilio F.; Luo, Minkui; Akabas, Myles H.; Schramm, Vern L.

2008-01-01

Plasmodium falciparum is a purine auxotroph, salvaging purines from erythrocytes for synthesis of RNA and DNA. Hypoxanthine is the key precursor for purine metabolism in Plasmodium. Inhibition of hypoxanthine-forming reactions in both erythrocytes and parasites is lethal to cultured P. falciparum. We observed that high concentrations of adenosine can rescue cultured parasites from purine nucleoside phosphorylase and adenosine deaminase blockade but not when erythrocyte adenosine kinase is also inhibited. P. falciparum lacks adenosine kinase but can salvage AMP synthesized in the erythrocyte cytoplasm to provide purines when both human and Plasmodium purine nucleoside phosphorylases and adenosine deaminases are inhibited. Transport studies in Xenopus laevis oocytes expressing the P. falciparum nucleoside transporter PfNT1 established that this transporter does not transport AMP. These metabolic patterns establish the existence of a novel nucleoside monophosphate transport pathway in P. falciparum. PMID:18799466

Optical Assay of Erythrocyte Function in Banked Blood

Science.gov (United States)

Bhaduri, Basanta; Kandel, Mikhail; Brugnara, Carlo; Tangella, Krishna; Popescu, Gabriel

2014-09-01

Stored red blood cells undergo numerous biochemical, structural, and functional changes, commonly referred to as storage lesion. How much these changes impede the ability of erythrocytes to perform their function and, as result, impact clinical outcomes in transfusion patients is unknown. In this study we investigate the effect of the storage on the erythrocyte membrane deformability and morphology. Using optical interferometry we imaged red blood cell (RBC) topography with nanometer sensitivity. Our time-lapse imaging quantifies membrane fluctuations at the nanometer scale, which in turn report on cell stiffness. This property directly impacts the cell's ability to transport oxygen in microvasculature. Interestingly, we found that cells which apparently maintain their normal shape (discocyte) throughout the storage period, stiffen progressively with storage time. By contrast, static parameters, such as mean cell hemoglobin content and morphology do not change during the same period. We propose that our method can be used as an effective assay for monitoring erythrocyte functionality during storage time.

Mutagenic assessment of Lithobates catesbeianus tadpoles exposed to the 2,4-D herbicide in a simulated realistic scenario.

Science.gov (United States)

Mesak, Carlos; de Oliveira Mendes, Bruna; de Oliveira Ferreira, Raíssa; Malafaia, Guilherme

2018-05-01

The aim of the current study is to assess possible erythrocyte mutagenic effects on Lithobates catesbeianus tadpoles exposed to water contaminated with 2,4-D. In order to do so, tadpoles were exposed to a predictive and environmentally relevant herbicide concentration (1.97 mg/L), which is likely to be found in lentic environments formed by superficial water runoffs in pasture areas where the herbicide was applied. The micronucleus test, as well as tests for other nuclear abnormalities, was conducted after 3, 5, and 9 days of exposure (d.e.). Changes in the biomass and mouth-cloaca length or interference in the larval development of the animals (in the three evaluated times) were not recorded. However, tadpoles exposed to 2,4-D showed the highest total number of nuclear abnormalities, as well as the highest frequency of binucleated erythrocytes and kidney-shaped nuclei (shortly after 3 d.e.). The micronucleus frequency was also higher in animals exposed to 2,4-D (in the 3rd, 5th, and 9th d.e.), as well as the frequency of binucleated cells (3rd, 5th, and 9th d.e.) presenting notched (9th d.e.) and blebbled (9th d.e.) nuclei in comparison to those of the control, after 5 and 9 days of exposure. Therefore, the current study is a pioneer in showing that 2,4-D has a mutagenic effect on L. catesbeianus tadpoles, even at low concentrations (environmentally relevant) and for a short period of time, a fact that may lead to direct losses in anuran populations living in areas adjacent to those subjected to 2,4-D herbicide application.

The osmotic fragility of human erythrocytes is inhibited by laser irradiation

International Nuclear Information System (INIS)

Habodaszova, D.; Sikurova, L.; Waczulikova, I.

2004-01-01

In this study we investigated the influence of green laser irradiation (532 nm, 30 mW, 31,7 J/cm 2 ) on the membrane integrity of human erythrocytes and compared the results with the effect of infrared laser irradiation (810 nm, 50 mW, 31,3 J/cm 2 ). To evaluate the membrane integrity of erythrocytes, one clinical parameter, the osmotic fragility, was investigated. We observed a decrease in osmotic fragility of the erythrocytes after irradiation by the green laser light as well as by the infrared laser compared to non-irradiated controls (Authors)

Unusual bone marrow visualization with sup(99m)Tc-damaged erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Dolgova-Korubin, V; Simova, N

1982-05-01

A visualization of the bone marrow and of the spleen was obtained with sup(99m)Tc-labeled N-ethylmaleimide (NEM) damaged erythrocytes in a patient with systemic lupus erythematosus. This phenomenon could be produced both with autologous and homologous red cells. The patient's NEM-damaged erythrocytes given to a healthy patient did not produce a visualization of the marrow. Such an observation was not present in a series of healthy persons and patients with different disorders to whom labeled and damaged erythrocytes were administered, and has not been reported in the literature so far.

New Insight into Erythrocyte through In Vivo Surface-Enhanced Raman Spectroscopy

DEFF Research Database (Denmark)

Brazhe, Nadezda A.; Abdali, Salim; Brazhe, Alexey R.

2009-01-01

containing erythrocytes in their normal physiological environment in a mixture of colloid solution with silver nanoparticles and the procedure for the optimization of SERS conditions to achieve high signal enhancement without affecting the properties of living erythrocytes. By means of three independent...... techniques, we demonstrate that under the proposed conditions a colloid solution of silver nanoparticles does not affect the properties of erythrocytes. For the first time to our knowledge, we describe how to use the SERS-RS approach to study two populations of hemoglobin molecules inside an intact living...

Investigating the function of F_c -specific binding of IgM to Plasmodium falciparum erythrocyte membrane protein 1 mediating erythrocyte rosetting

DEFF Research Database (Denmark)

Stevenson, Liz; Huda, Pie; Jeppesen, Anine

2015-01-01

of opsonized infected erythrocytes (IEs) without compromising the placental IE adhesion mediated by this PfEMP1 type. IgM also binds via Fc to several other PfEMP1 proteins, where it has been proposed to facilitate rosetting (binding of uninfected erythrocytes to a central IE). To further dissect...

Alkaline Comet Assay and Micronucleus Test Parameters in Children Exposed to Diagnostic X-Ray Examination

International Nuclear Information System (INIS)

Gajski, G.; Geric, M.; Garaj-Vrhovac, V.; Milkovic, Dj.; Beck, N.; Ranogajec-Komor, M.; Miljanic, S.; Knezevic, Z.

2011-01-01

Chest radiograms represent the basic radiological examination of thorax and are the most frequently performed radiological diagnostic procedure in the child population. Understanding the risks of low doses of radiation is an important aspect in the risk benefit analysis in paediatric populations. To provide the best care for the young patients the effects of radiation should be minimized thus chest X-rays must be performed by highest standards to ensure that the young patient has the lowest risk possible. Since children are the most sensitive to radiation, there is a need for follow up of the young populations that receive these X-ray diagnostic examinations. Follow up would be especially advisable for children that are at higher risk of radiation induced damage, for example children with a predisposition to DNA damage, or for children that are constantly exposed to numerous radiological examinations due to their illness. In that manner, present study was undertaken to evaluate application of different dosimetry systems in conjunction with alkaline comet assay and micronucleus test for the assessment of different types of DNA and chromosomal alterations in child population exposed to acute diagnostic X-rays examination. For that purpose doses were measured using thermoluminescence (TL) and radiophotoluminescent (RPL) dosimetry systems. The study demonstrated that immediately after exposure to diagnostic X-irradiation, mean percentage of DNA in tail of the comets, which is indirect measures of DNA damage, was significantly changed. The same was noticed for mean total number of micronuclei as well. It was shown that children with pulmonary diseases subjected to diagnostic procedure develop a significant increase in mean total number of each measured parameter which are the biomarkers of genetic damage for carcinogenesis, than prior to diagnostic procedure and that interindividual differences exist for each monitored child. Our results show that genetic damage arises

A Lectin-Like Receptor is Involved in Invasion of Erythrocytes by Plasmodium falciparum

Science.gov (United States)

Jungery, M.; Pasvol, G.; Newbold, C. I.; Weatherall, D. J.

1983-02-01

Glycophorin both in solution and inserted into liposomes blocks invasion of erythrocytes by the malaria parasite Plasmodium falciparum. Furthermore, one sugar, N-acetyl-D-glucosamine (GlcNAc), completely blocks invasion of the erythrocyte by this parasite. GlcNAc coupled to bovine serum albumin to prevent the sugar entering infected erythrocytes was at least 100,000 times more effective than GlcNAc alone. Bovine serum albumin coupled to lactose or bovine serum albumin alone had no effect on invasion. These results suggest that the binding of P. falciparum to erythrocytes is lectin-like and is determined by carbohydrates on glycophorin.

Triggering of Suicidal Erythrocyte Death by Regorafenib

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Jens Zierle

2016-01-01

Full Text Available Background/Aims: The multikinase inhibitor regorafenib is utilized for the treatment of malignancy. The substance is effective in part by triggering suicidal death or apoptosis of tumor cells. Side effects of regorafenib include anemia. At least in theory, regorafenib induced anemia could result from stimulated suicidal erythrocyte death or eryptosis, 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, oxidative stress and ceramide. The present study explored, whether regorafenib induces eryptosis and, if so, whether it is effective up- and/or downstream of Ca2+. Methods: To this end, phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence, and ceramide abundance utilizing specific antibodies. Results: A 48 hours exposure of human erythrocytes to regorafenib (≥ 0.5 µg/ml significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter (≥ 1.25 µg/ml, but did not significantly increase Fluo3-fluorescence, DCFDA fluorescence or ceramide abundance. The effect of regorafenib on annexin-V-binding and forward scatter was not significantly blunted by removal of extracellular Ca2+. Regorafenib (5 µg/ml significantly augmented the increase of annexin-V-binding, but significantly blunted the decrease of forward scatter following treatment with the Ca2+ ionophore ionomycin. Conclusions: Regorafenib triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part downstream of Ca2+.

Triggering of Suicidal Erythrocyte Death by Regorafenib.

Science.gov (United States)

Zierle, Jens; Bissinger, Rosi; Bouguerra, Ghada; Abbès, Salem; Lang, Florian

2016-01-01

The multikinase inhibitor regorafenib is utilized for the treatment of malignancy. The substance is effective in part by triggering suicidal death or apoptosis of tumor cells. Side effects of regorafenib include anemia. At least in theory, regorafenib induced anemia could result from stimulated suicidal erythrocyte death or eryptosis, 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), oxidative stress and ceramide. The present study explored, whether regorafenib induces eryptosis and, if so, whether it is effective up- and/or downstream of Ca2+. To this end, phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence, and ceramide abundance utilizing specific antibodies. A 48 hours exposure of human erythrocytes to regorafenib (≥ 0.5 µg/ml) significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter (≥ 1.25 µg/ml), but did not significantly increase Fluo3-fluorescence, DCFDA fluorescence or ceramide abundance. The effect of regorafenib on annexin-V-binding and forward scatter was not significantly blunted by removal of extracellular Ca2+. Regorafenib (5 µg/ml) significantly augmented the increase of annexin-V-binding, but significantly blunted the decrease of forward scatter following treatment with the Ca2+ ionophore ionomycin. Regorafenib triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part downstream of Ca2+. © 2016 The Author(s) Published by S. Karger AG, Basel.

Fucoxanthin Induced Suicidal Death of Human Erythrocytes

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Marilena Briglia

2015-12-01

Full Text Available Background/Aims: Fucoxanthin, a carotenoid isolated from brown seaweeds, induces suicidal death or apoptosis of tumor cells and is thus considered for the treatment or prevention of malignancy. In analogy to apoptosis of nucleated cell, erythrocytes may enter eryptosis, the suicidal death characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i, oxidative stress and activation of p38 kinase or protein kinase C. The present study explored, whether and how fucoxanthin induces eryptosis. Methods: Phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, and abundance of reactive oxygen species (ROS from DCFDA dependent fluorescence and lipid peroxidation using BODIPY fluoresence. Results: A 48 hours exposure of human erythrocytes to fucoxanthin significantly increased the percentage of annexin-V-binding cells (≥ 50 µM, significantly decreased average forward scatter (≥ 25 µM, significantly increased hemolysis (≥ 25 µM, significantly increased Fluo3-fluorescence (≥ 50 µM, significantly increased lipid peroxidation, but did not significantly modify DCFDA fluorescence. The effect of fucoxanthin on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+, and was insensitive to p38 kinase inhibitor skepinone (2 µM and to protein kinase C inhibitor calphostin (100 nM. Conclusion: Fucoxanthin triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of Ca2+ entry.

Stimulation of Suicidal Erythrocyte Death by Garcinol

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Antonella Fazio

2015-09-01

Full Text Available Background/Aims: The benzophenone garcinol from dried fruit rind of Garcinia indica counteracts malignancy, an effect at least in part due to stimulation of apoptosis. The proapototic effect of garcinol is attributed in part to inhibition of histone acetyltransferases and thus modification of gene expression. Moreover, garcinol triggers mitochondrial depolarisation. Erythrocytes lack gene expression and mitochondria but are nevertheless able to enter apoptosis-like suicidal death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include oxidative stress, energy depletion and Ca2+ entry with increase of cytosolic Ca2+ activity ([Ca2+]i. The present study explored, whether and how garcinol induces eryptosis. Methods: To this end, phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, hemolysis from hemoglobin release, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence and cytosolic ATP levels utilizing a luciferin-luciferase-based assay. Results: A 24 hours exposure of human erythrocytes to garcinol (2.5 or 5 µM significantly increased the percentage of annexin-V-binding cells. Garcinol decreased (at 1 µM and 2.5 µM or increased (at 5 µM forward scatter. Garcinol (5 µM further increased Fluo3-fluorescence, increased DCFDA fluorescence, and decreased cytosolic ATP levels. The effect of garcinol on annexin-V-binding was significantly blunted, but not abolished by removal of extracellular Ca2+. Conclusions: Garcinol triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect in part due to stimulation of ROS formation, energy depletion and Ca2+ entry.

Induction of Suicidal Erythrocyte Death by Novobiocin

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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.

[The 2,3-diphosphoglycerate shunt and stabilization of the ATP level in mammalian erythrocytes].

Science.gov (United States)

Ataullakhanov, A I; Ataullakhanov, F I; Vitvitskiĭ, V M; Zhabotinskiĭ, A M; Pichugin, A V

1985-06-01

The mechanisms of regulation of energy metabolism in erythrocytes of various mammalian species were investigated. In native erythrocytes of man, sheep, cow, dog and mouse the dependencies of the rates of glucose uptake on ATP concentration (i.e., regulatory parameters of glycolysis) were measured. These parameters plotted in normalized coordinates are not species-specific (invariant). The dependence of the rate of ATP-consuming processes on ATP concentration has been studied for the first time in intact mammalian erythrocytes. This dependence was found to be linear only in the species, in whose erythrocytes the activity of 2,3-diphosphoglycerate shunt is practically zero. In all species under study, the stabilization of ATP level is provided for mainly by the hexokinase-phosphofructokinase system. A comparison of regulatory mechanisms of energy metabolism in mammalian (sheep, cow) erythrocytes, in which the 2,3-diphosphoglycerate shunt is absent, with human and animal erythrocytes, in which this pathway is active, points to the important role of the 2,3-diphosphoglycerate shunt in regulation of energy conversion in erythrocytes. This shunt operates as an additional stabilizer protecting the cell from extremal influences.

Inhibition of Suicidal Erythrocyte Death by Indirubin-3’-Monoxime

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Chunqiu Liu

2018-02-01

Full Text Available Background/Aims: 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. Methods: 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. Results: 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. Conclusions: 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.

Antimutagenic Effect of Hibiscus sabdariffa L. Aqueous Extract on Rats Treated with Monosodium Glutamate

Science.gov (United States)

Kerkhoff, Jacqueline; Vieira Júnior, Gerardo Magela; de Campos, Kleber Eduardo; Sugui, Marina Mariko

2017-01-01

Hibiscus sabdariffa L. is a plant of the Malvaceae family, commonly known as roselle. H. sabdariffa is known to contain antioxidant, cholesterol-lowering, antiobesity, insulin resistance reduction, antihypertensive, and skin cancer chemopreventive properties. This study evaluated the effects of H. sabdariffa aqueous extract against cyclophosphamide (CPA, 25 mg/Kg) induced damage to DNA in male Wistar rats by micronucleus test. Samples of H. sabdariffa calyx were obtained in the municipality of Barra do Garças, Mato Grosso, Brazil. The aqueous extract was prepared by infusion and each animal received a daily dose of 400 mg/Kg by gavage for 15 consecutive days of treatment. The presence of anthocyanins was confirmed by ferric chloride test and phenolic compounds using high-performance liquid chromatography, with emphasis on the identification of rutin. The animals were sacrificed by deepening of anaesthesia to obtain bone marrow and determination of the frequency of micronucleated polychromatic erythrocytes. The group treated with the aqueous extract of H. sabdariffa revealed a 91% reduction in micronucleus frequency when compared with the positive control group. Under the conditions tested, H. sabdariffa L. presented a protective effect to CPA-induced damage to DNA of the treated animals, and it is a potential candidate as a chemopreventive agent against carcinogenesis. PMID:28197528

Antimutagenic Effect of Hibiscus sabdariffa L. Aqueous Extract on Rats Treated with Monosodium Glutamate

Directory of Open Access Journals (Sweden)

Ana Carla Guidini Valentini Gheller

2017-01-01

Full Text Available Hibiscus sabdariffa L. is a plant of the Malvaceae family, commonly known as roselle. H. sabdariffa is known to contain antioxidant, cholesterol-lowering, antiobesity, insulin resistance reduction, antihypertensive, and skin cancer chemopreventive properties. This study evaluated the effects of H. sabdariffa aqueous extract against cyclophosphamide (CPA, 25 mg/Kg induced damage to DNA in male Wistar rats by micronucleus test. Samples of H. sabdariffa calyx were obtained in the municipality of Barra do Garças, Mato Grosso, Brazil. The aqueous extract was prepared by infusion and each animal received a daily dose of 400 mg/Kg by gavage for 15 consecutive days of treatment. The presence of anthocyanins was confirmed by ferric chloride test and phenolic compounds using high-performance liquid chromatography, with emphasis on the identification of rutin. The animals were sacrificed by deepening of anaesthesia to obtain bone marrow and determination of the frequency of micronucleated polychromatic erythrocytes. The group treated with the aqueous extract of H. sabdariffa revealed a 91% reduction in micronucleus frequency when compared with the positive control group. Under the conditions tested, H. sabdariffa L. presented a protective effect to CPA-induced damage to DNA of the treated animals, and it is a potential candidate as a chemopreventive agent against carcinogenesis.

Antimutagenic Effect of Hibiscus sabdariffa L. Aqueous Extract on Rats Treated with Monosodium Glutamate.

Science.gov (United States)

Gheller, Ana Carla Guidini Valentini; Kerkhoff, Jacqueline; Vieira Júnior, Gerardo Magela; de Campos, Kleber Eduardo; Sugui, Marina Mariko

2017-01-01

Hibiscus sabdariffa L. is a plant of the Malvaceae family, commonly known as roselle. H. sabdariffa is known to contain antioxidant, cholesterol-lowering, antiobesity, insulin resistance reduction, antihypertensive, and skin cancer chemopreventive properties. This study evaluated the effects of H. sabdariffa aqueous extract against cyclophosphamide (CPA, 25 mg/Kg) induced damage to DNA in male Wistar rats by micronucleus test. Samples of H. sabdariffa calyx were obtained in the municipality of Barra do Garças, Mato Grosso, Brazil. The aqueous extract was prepared by infusion and each animal received a daily dose of 400 mg/Kg by gavage for 15 consecutive days of treatment. The presence of anthocyanins was confirmed by ferric chloride test and phenolic compounds using high-performance liquid chromatography, with emphasis on the identification of rutin. The animals were sacrificed by deepening of anaesthesia to obtain bone marrow and determination of the frequency of micronucleated polychromatic erythrocytes. The group treated with the aqueous extract of H. sabdariffa revealed a 91% reduction in micronucleus frequency when compared with the positive control group. Under the conditions tested, H. sabdariffa L. presented a protective effect to CPA-induced damage to DNA of the treated animals, and it is a potential candidate as a chemopreventive agent against carcinogenesis.

Erythrocytes in muscular dystrophy. Investigation with 31P nuclear magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Sarpel, G.; Lubansky, H.J.; Danon, M.J.; Omachi, A.

1981-01-01

Phosphorus 31 nuclear magnetic resonance ( 31 P NMR) signals were recorded from intact human erythrocytes for 16 hours. Total phosphate concentration, which was estimated as the sum of the individual 31 P signals, was 25% lower in erythrocytes from men with myotonic dystrophy than in control erythrocytes. The inorganic-phosphate fraction contained the highest average phosphate concentration over the 16-hour period, and made the major contribution to the difference in total phosphate between the two groups. This result was not observed in erythrocytes from either women with myotonic dystrophy or patients with Duchenne's dystrophy and may be due to a change in cell membrane permeability to inorganic phosphate, which leads to lower steady-state concentrations of the intracellular phosphates

Erythrocytes in muscular dystrophy. Investigation with 31P nuclear magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Sarpel, G.; Lubansky, H.J.; Danon, M.J.; Omachi, A.

1981-01-01

Phosphorus 31 nuclear magnetic resonance (31P NMR) signals were recorded from intact human erythrocytes for 16 hours. Total phosphate concentration, which was estimated as the sum of the individual 31P signals, was 25% lower in erythrocytes from men with myotonic dystrophy than in control erythrocytes. The inorganic-phosphate fraction contained the highest average phosphate concentration over the 16-hour period, and made the major contribution to the difference in total phosphate between the two groups. This result was not observed in erythrocytes from either women with myotonic dystrophy or patients with Duchenne's dystrophy and may be due to a change in cell membrane permeability to inorganic phosphate, which lead to lower steady-state concentrations of the intracellular phosphates

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).

Plasma viscosity or erythrocyte sedimentation rate in the diagnosis of giant cell arteritis?

OpenAIRE

Brittain, G. P.; McIlwaine, G. G.; Bell, J. A.; Gibson, J. M.

1991-01-01

Plasma viscosity (PV) has replaced the erythrocyte sedimentation rate (ESR) as a routine laboratory test in many hospitals. The finding of a normal PV but raised ESR in a case of biopsy proved giant cell arteritis (GCA) cast doubt on this substitution in cases of suspected GCA. To assess the equivalence of PV and ESR in the diagnosis of this disease 40 suspected cases were prospectively investigated with both tests. The correlation between the two tests was good (r = 0.742, p less than 0.0001...

Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers

International Nuclear Information System (INIS)

Quintanar-Escorza, M.A.; Gonzalez-Martinez, M.T.; Navarro, L.; Maldonado, M.; Arevalo, B.; Calderon-Salinas, J.V.

2007-01-01

Erythrocytes are the route of lead distribution to organs and tissues. The effect of lead on calcium homeostasis in human erythrocytes and other excitable cells is not known. In the present work we studied the effect of lead intoxication on the uptake and efflux (measured as (Ca 2+ -Mg 2+ )-ATPase activity) of calcium were studied in erythrocytes obtained from lead-exposed workers. Blood samples were taken from 15 workers exposed to lead (blood lead concentration 74.4 ± 21.9 μg/dl) and 15 non-exposed workers (9.9 ± 2 μg/dl). In erythrocytes of lead-exposed workers, the intracellular free calcium was 79 ± 13 nM, a significantly higher concentration (ANOVA, P 2+ -Mg 2+ )-ATPase activity. Lipid peroxidation was 1.7-fold higher in erythrocytes of lead-exposed workers as compared with control. The alteration on calcium equilibrium in erythrocytes is discussed in light of the toxicological effects in lead-exposed workers

p53 protein expression versus micronucleus induction as an indicator of DNA damage

International Nuclear Information System (INIS)

Hickman, A.W.; Carpenter, T.R.; Johnson, N.F.

1994-01-01

In vitro assays for detecting DNA damage play an important role in evaluating the possible adverse health effects of chemical compounds. Exposure to many DNA-damaging agents in vitro has been shown to cause elevated levels of the tumor-suppressor protein p53. Work in our laboratory has shown that induction of the p53 protein is useful as a biodosimeter for determining the radiation dose to cells. The purpose of this investigation was to compare the sensitivity of this assay to that of micronucleus induction, which is commonly used as a marker of radiation-induced damage

Tuning SERS for living erythrocytes

DEFF Research Database (Denmark)

Brazhe, Nadezda; Parshina, E.Y.; Khabanova, V.V.

2013-01-01

Surface-enhanced Raman spectroscopy (SERS) is a unique technique to study submembrane hemoglobin (Hbsm) in erythrocytes. We report the detailed design of SERS experiments on living erythrocytes to estimate dependence of the enhancemen t factor for main Raman bands of Hbsm on silver nanoparticle (Ag......NP) properties. We demonstrate that the enhancement factor for 4/A1g, 10/B1g and A2g Raman bands of Hbsm varies from 105 to 107 under proposed experimental conditions with 473 nm laser excitation. For the first time we show that the enhancement of Raman scattering increases with the increase in the relative...... between small AgNPs and Hbsm and, consequently, leads to the higher enhancement of Raman scattering of Hbsm. The enhancement of higher wavenumber bands 10/B1g and A2g is more sensitive to AgNPs' size and the relative amount of small AgNPs than the enhancement of the lower wavenumber band 4/A1g. This can...

Radiogenotoxicological effect of signal nuclide 134Cs on somatic and germ cells

Institute of Scientific and Technical Information of China (English)

ZhuShou－Peng; XiaFen; 等

1997-01-01

Chromosome at aberation rates in bone marrow cells and micronucleus formation in bone marrow polychromatic erythrocytes both rise with increase in radioactivities of 134Cs,and can be fitted to power functions of radioactivities of 134Cs.In spermatogonia 134Cs mainly induced chromatid breakage,and abnormalities in sperm can also be experessed as power functions of radioactivities of 134 Cs.

NMR studies of transmembrane electron transport in human erythrocytes

International Nuclear Information System (INIS)

Kennett, E.C.; Bubb, W.A.; Kuchel, P.W.

2002-01-01

Full text: Electron transport systems exist in the plasma membranes of all cells. These systems appear to play a role in cell growth and proliferation, intracellular signalling, hormone responses, apoptotic events, cell defence and perhaps most importantly they enable the cell to respond to changes in the redox state of both the intra- and extracellular environments. Previously, 13 C NMR has been used to study transmembrane electron transport in human erythrocytes, specifically the reduction of extracellular 13 C-ferricyanide. NMR is a particularly useful tool for studying such systems as changes in the metabolic state of the cell can be observed concomitantly with extracellular reductase activity. We investigated the oxidation of extracellular NADH by human erythrocytes using 1 H and 31 P NMR spectroscopy. Recent results for glucose-starved human erythrocytes indicate that, under these conditions, extracellular NADH can be oxidised at the plasma membrane with the electron transfer across the membrane resulting in reduction of intracellular NAD + . The activity is inhibited by known trans-plasma membrane electron transport inhibitors (capsaicin and atebrin) and is unaffected by inhibition of the erythrocyte Band 3 anion transporter. These results suggest that electron import from extracellular NADH allows the cell to re-establish a reducing environment after the normal redox balance is disturbed

Change of properties of erythrocytes membranes in UV-irradiated blood

International Nuclear Information System (INIS)

Gromov, A.E.; Vetosh, A.N.; Nikonchuk, N.P.; Perelygin, V.G.; Ruzanov, I.B.

1986-01-01

An increase in erythrocyte membrane permeability for gases, decrease in erythrocyte thermal stability and activation of membrane transport systems after autotransfusion of UV-irradiated blood are ascertained. The data obtained testify to the fact that the greatest changes in membranes take place not directly under irradiation but after the introduction of irradiated blood to the organism

Exo-erythrocytic development of avian malaria and related haemosporidian parasites.

Science.gov (United States)

Valkiūnas, Gediminas; Iezhova, Tatjana A

2017-03-03

Avian malaria parasites (Plasmodium spp.) and related haemosporidians (Haemosporida) are responsible for diseases which can be severe and even lethal in avian hosts. These parasites cause not only blood pathology, but also damage various organs due to extensive exo-erythrocytic development all over the body, which is not the case during Plasmodium infections in mammals. However, exo-erythrocytic development (tissue merogony or schizogony) remains the most poorly investigated part of life cycle in all groups of wildlife haemosporidian parasites. In spite of remarkable progress in studies of genetic diversity, ecology and evolutionary biology of avian haemosporidians during the past 20 years, there is not much progress in understanding patterns of exo-erythrocytic development in these parasites. The purpose of this review is to overview the main information on exo-erythrocytic development of avian Plasmodium species and related haemosporidian parasites as a baseline for assisting academic and veterinary medicine researchers in morphological identification of these parasites using tissue stages, and to define future research priorities in this field of avian malariology. The data were considered from peer-reviewed articles and histological material that was accessed in zoological collections in museums of Australia, Europe and the USA. Articles describing tissue stages of avian haemosporidians were included from 1908 to the present. Histological preparations of various organs infected with the exo-erythrocytic stages of different haemosporidian parasites were examined. In all, 229 published articles were included in this review. Exo-erythrocytic stages of avian Plasmodium, Fallisia, Haemoproteus, Leucocytozoon, and Akiba species were analysed, compared and illustrated. Morphological characters of tissue stages that can be used for diagnostic purposes were specified. Recent molecular studies combined with histological research show that avian haemosporidians are more

Specific binding of beta-endorphin to normal human erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Chenet, B.; Hollis, V. Jr.; Kang, Y.; Simpkins, C.

1986-03-05

Beta-endorphin (BE) exhibits peripheral functions which may not be mediated by interactions with receptors in the brain. Recent studies have demonstrated binding of BE to both opioid and non-opioid receptors on lymphocytes and monocytes. Abood has reported specific binding of /sup 3/H-dihydromorphine in erythrocytes. Using 5 x 10/sup -11/M /sup 125/I-beta-endorphin and 10/sup -5/M unlabeled BE, they have detected 50% specific binding to human erythrocytes. This finding is supported by results from immunoelectron microscopy using rabbit anti-BE antibody and biotinylated secondary antibody with avidin-biotin complexes horseradish peroxidase. Binding is clearly observed and is confined to only one side of the cells. Conclusions: (1) BE binding to human erythrocytes was demonstrated by radioreceptor assay and immunoelectron microscopy, and (2) BE binding sites exist on only one side of the cells.

Descriptive parameters of the erythrocyte aggregation phenomenon using a laser transmission optical chip

Science.gov (United States)

Toderi, Martín A.; Castellini, Horacio V.; Riquelme, Bibiana D.

2017-01-01

The study of red blood cell (RBC) aggregation is of great interest because of its implications for human health. Altered RBC aggregation can lead to microcirculatory problems as in vascular pathologies, such as hypertension and diabetes, due to a decrease in the erythrocyte surface electric charge and an increase in the ligands present in plasma. The process of erythrocyte aggregation was studied in stasis situation (free shear stresses), using an optical chip based on the laser transmission technique. Kinetic curves of erythrocyte aggregation under different conditions were obtained, allowing evaluation and characterization of this process. Two main characteristics of blood that influence erythrocyte aggregation were analyzed: the erythrocyte surface anionic charge (EAC) after digestion with the enzyme trypsin and plasmatic protein concentration in suspension medium using plasma dissolutions in physiological saline with human albumin. A theoretical approach was evaluated to obtain aggregation and disaggregation ratios by syllectograms data fitting. Sensible parameters (Amp100, t) regarding a reduced erythrocyte EAC were determined, and other parameters (AI, M-Index) resulted that are representative of a variation in the plasmatic protein content of the suspension medium. These results are very useful for further applications in biomedicine.

Evaluation of repeated dose micronucleus assays of the liver using N-nitrosopyrrolidine: a report of the collaborative study by CSGMT/JEMS.MMS.

Science.gov (United States)

Ogawa, Izumi; Hagioa, Soichiro; Furukawa, Satoshi; Abe, Masayoshi; Kuroda, Yusuke; Hayashi, Seigo; Wako, Yumi; Kawasako, Kazufumi

2015-03-01

The repeated dose liver micronucleus (RDLMN) assay has the potential to detect liver carcinogens, and can be integrated into a general toxicological study. To assess the performance of the assay, N-nitrosopyrrolidine (NPYR), a genotoxic hepatocarcinogen, was tested in 14- or 28-day RDLMN assays. NPYR was orally administered to rats at a daily dose of 25, 50 or 100 mg/kg. One day after the last administration, a portion of the liver was removed and hepatocyte micronucleus (MN) specimens were prepared by the new method recently established by Narumi et al. In addition, a bone marrow MN assay and a histopathological examination of the liver were conducted. The detection of Phospho-Histone H3 was performed by immunohistochemistry to evaluate the proliferation rate of hepatocytes. The results showed significant increase in the number of micronucleated hepatocytes and Phospho-Histone H3-positive cells from the lowest dose in both 14- and 28-day RDLMN assays. On the other hand, the bone marrow MN assay yielded a negative result, which was in accordance with the existing report of the bone marrow MN assay using mice. Upon histopathological examination, inflammatory lesions and hypertrophy were noted, which may explain the increase in the hepatocyte proliferation and the enhancement of MN induction by NPYR. Our findings indicate that the RDLMN assay could be a useful tool for comprehensive risk assessment of carcinogenicity by providing information on both genotoxicity and histopathology when integrated into a general repeat dosing toxicity assay.

Aquaporin-1-Mediated Effects of Low Level He-Ne Laser Irradiation on Human Erythrocytes

Directory of Open Access Journals (Sweden)

Gang-Yue Luo

2012-01-01

Full Text Available The role of membrane aquaporin-1 (APQ-1 in the photobiomodulation (PBM on erythrocyte deformability will be studied in this paper with human dehydrated erythrocytes as echinocytic shape alterations lead to decreased cellular deformability. Human dehydrated erythrocytes were irradiated with low intensity He-Ne laser irradiation (LHNL at 0.9, 1.8, 2.7, and 4.4 mW/cm2 for 5, 15, and 30 min, respectively, and APQ-1 inhibitor, 0.2 μmol/L HgCl2, was used to study the role of APQ-1 in mediating PBM with LHNL at 4.4 mW/cm2 for 5 min. Comprehensive morphological parameters of an intact cell such as contact area, perimeter, roundness and erythrocyte elongation index (EEI were measured to characterize erythrocyte deformability with fast micro multi-channel spectrophotometer. It was observed that the dosage of LHNL improvement of the morphological parameters of dehydrated erythrocytes was morphological-parameter-dependent, but the Bunsen-Roscoe rule did not hold for roundness. The LHNL at 4.4 mW/cm2 for 5 min significantly improved the contact area (P<0.05 and EEI (P<0.05 of the dehydrated erythrocytes, but the improvement was significantly inhibited by 0.2 μmol/L HgCl2 (P<0.05. It was concluded that AQP-1 might mediate the effects of LHNL on erythrocyte deformability, which supports the membranotropic mechanism of PBM.

Patient exposure and micronucleus assay during extracorporeal shock wave lithotripsy (ESWL) for kidney stones

International Nuclear Information System (INIS)

Shao, M.

1992-01-01

This study reports results of radiation exposure to 20 patients with kidney stones during Extracorporeal Shock Wave Lithotripsy (ESWL). A domestically made JT-ESWL-I Lithotripter was used. Data indicated that the amount of radiation exposure is related to the numbers, size, location and radiodensity of the stone, and also the number of shock wave and the time of fluoroscopy exposure given to the patients. The results of the micronucleus frequency of lymphocytes assay in the human peripheral blood are reported. This effect increased with increasing radiation exposure doses. (author). 4 refs., 2 tabs

Analysis of the Genotoxic Effects of Mobile Phone Radiation using Buccal Micronucleus Assay: A Comparative Evaluation.

Science.gov (United States)

Banerjee, Sumita; Singh, Narendra Nath; Sreedhar, Gadiputi; Mukherjee, Saikat

2016-03-01

Micronucleus (MN) is considered to be a reliable marker for genotoxic damage and it determines the presence and the extent of the chromosomal damage. The MN is formed due to DNA damage or chromosomal disarrangements. The MN has a close association with cancer incidences. In the new era, mobile phones are constantly gaining popularity specifically in the young generation, but this device uses radiofrequency radiation that may have a possible carcinogenic effect. The available reports related to the carcinogenic effect of mobile radiation on oral mucosa are contradictory. To explore the effects of mobile phone radiation on the MN frequency in oral mucosal cells. The subjects were divided into two major groups: low mobile phone users and high mobile phone users. Subjects who used their mobile phone since less than five years and less than three hours a week comprised of the first group and those who used their mobile since more than five years and more than 10 hours a week comprised of the second group. Net surfing and text messaging was not considered in this study. Exfoliated buccal mucosal cells were collected from both the groups and the cells were stained with DNA-specific stain acridine orange. Thousand exfoliated buccal mucosal cells were screened and the cells which were positive for micronuclei were counted. The micronucleus frequency was represented as mean±SD, and unpaired Student t-test was used for intergroup comparisons. The number of micronucleated cells/ 1000 exfoliated buccal mucosal cells was found to be significantly increased in high mobile phone users group than the low mobile phone users group. The use of mobile phone with the associated complaint of warmth around the ear showed a maximum increase in the number of micronucleated cells /1000 exfoliated buccal mucosal cells. Mobile phone radiation even in the permissible range when used for longer duration causes significant genotoxicity. The genotoxicity can be avoided to some extent by the

Spontaneous micronucleus frequencies in human peripheral blood lymphocytes as a screening test for an individual variation in a different population and radiation-induced micronucleus induction

International Nuclear Information System (INIS)

Kang, Chang-Mo; Jeon, Hye-Jeong; Cho, Chul-Koo

2004-01-01

Our studies were to evaluate the role of epigenetic factors in the variation of radiosensitivity on human peripheral blood lymphocytes by measuring the frequencies of micronucleus (MN) from 293 healthy subjects of different population for assessing the radiation health risk in Korea. We analyzed the frequencies of both spontaneous and in vitro 60 Co γ-rays or 50MeV neutron-induced MNs. The frequencies of spontaneous NMs not only vary greatly between individuals, but also working or living areas. The increased levels of cells with spontaneous MNs were observed with an increasing age. The frequencies of spontaneous MNs were significantly higher in females than in males. For both sexes, MN frequency was significantly and positively correlated with age. Age and gender are the most important demographic variables impacting on the MN index. Donors who had ever smoked showed significantly increased frequencies of MNs compared to nonsmokers. The main lifestyle factors influencing the MN index in the subjects are correlated significantly and positively with smoke while measuring the spontaneous frequencies of micronuclei. Therefore, it is evident that with regard to the application of MN assay all future studies to evaluate the association between radiosensitivity and susceptibility for radiation health risks in different populations should take into account the effect of age, gender and lifestyle. For the dose-response study, the induced MNs were observed at all doses, and the numerical changes according to doses. The dose-response curves were fitted with a linear-quadratic forms of the dose, and the results were different for γ-rays and neutrons significantly. Neutrons were more effective than γ-rays in producing MN with a dose-dependent manner. The frequency of MN varies with dose. The RBE for a micronuclei was 2.37 ± 0.17. The results suggested that the MN assay have a high potential to ensure appropriate quality control and a standard documentation protocol, which

[Age-related change in the alpha-tocopherolquinone/alpha-tocopherol ratio in the rat erythrocyte membrane].

Science.gov (United States)

Yanagawa, K; Takeda, H; Matsumiya, T; Takasaki, M

1999-05-01

alpha-Tocopherol (alpha-Toc), a lipophilic phenolic antioxidant that is localized mainly in the biomembrane, protects cells against oxidation-associated cytotoxicity by prevention of membrane lipid peroxidation, maintenance of the redox balance intracellular thiols and stabilization of the membrane structure. We investigated the age-related changes in redox dynamics of alpha-Toc in plasma and erythrocyte membrane of an elderly (66 weeks old) and young group (10 weeks old). Total, alpha-, beta + gamma-, delta-Toc and alpha-tocopherolquinone (alpha-TocQ) in plasma and erythrocyte membrane were determined by high-performance liquid chromatography (HPLC) with a series of multiple coulometric working electrodes (CWE). Rat venous blood sample was divided into plasma and erythrocyte layers by centrifugation, and then erythrocyte membrane sample was prepared according to the method of Dodge et al. under a stream of nitrogen. In plasma, total and alpha-Toc concentrations were increased, and beta + gamma-, delta-Toc and alpha-TocQ concentrations were decreased age-dependently. In the erythrocyte membrane, total, alpha-TocQ concentrations and three fractions of tocopherols decreased age-dependently. Also, a decrease in the alpha-TocQ/alpha-Toc ratio in erythrocyte membrane was observed in the elderly group. These findings suggest that the alpha-Toc uptake in erythrocyte membrane and utilization rate of alpha-Toc in erythrocyte membrane decline age-dependently. This decline may promote membrane lipid peroxidation. alpha-Toc redox dynamics in erythrocyte membrane were useful to investigate the pathophysiology of aging mechanisms related to oxidative stress.

Effect of dietary zinc deficiency on the endogenous phosphorylation and dephosphorylation of rat erythrocyte membrane

International Nuclear Information System (INIS)

Paterson, P.G.; Allen, O.B.; Bettger, W.J.

1987-01-01

The effect of dietary zinc deficiency on patterns of phosphorylation and dephosphorylation of rat erythrocyte membrane proteins and erythrocyte filterability was examined. Weanling male Wistar rats were fed an egg white-based diet containing less than 1.1 mg zinc/kg diet ad libitum for 3 wk. Control rats were either pair-fed or ad libitum-fed the basal diet supplemented with 100 mg zinc/kg diet. Net phosphorylation and dephosphorylation of erythrocyte membrane proteins were carried out by an in vitro assay utilizing [gamma- 32 P]ATP. The membrane proteins were subsequently separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the 32 P content of gel slices was counted by Cerenkov counting. Erythrocyte filterability was measured as the filtration time of suspensions of erythrocytes, both untreated and preincubated with diamide, under constant pressure. Erythrocyte ghosts from zinc-deficient rats demonstrated greater dephosphorylation of protein bands R1 plus R2 and R7 than pair-fed rats and greater net phosphorylation of band R2.2 than pair-fed or ad libitum-fed control rats (P less than 0.05). Erythrocytes from ad libitum-fed control rats showed significantly longer filtration times than those from zinc-deficient or pair-fed control rats. In conclusion, dietary zinc deficiency alters in vitro patterns of erythrocyte membrane protein phosphorylation and dephosphorylation, whereas the depression in food intake associated with the zinc deficiency increases erythrocyte filterability. 71 references

Genotoxicity tests on D-tagatose.

Science.gov (United States)

Kruger, C L; Whittaker, M H; Frankos, V H

1999-04-01

D-tagatose is a low-calorie sweetener that tastes like sucrose. Its genotoxic potential was examined in five standard assays: the Ames Salmonella typhimurium reverse mutation assay, the Escherichia coli/mammalian microsome assay, a chromosomal aberration assay in Chinese hamster ovary cells, a mouse lymphoma forward mutation assay, and an in vivo mouse micronucleus assay. D-tagatose was not found to increase the number of revertants per plate relative to vehicle controls in either the S. typhimurium tester strains or the WP2uvrA- tester strain with or without metabolic activation at doses up to 5000 microg/plate. No significant increase in Chinese hamster ovary cells with chromosomal aberrations was observed at concentrations up to 5000 microg/ml with or without metabolic activation. D-tagatose was not found to increase the mutant frequency in mouse lymphoma L5178Y cells with or without metabolic activation up to concentrations of 5000 microg/ml. D-tagatose caused no significant increase in micronuclei in bone marrow polychromatic erythrocytes at doses up to 5000 mg/kg. D-tagatose was not found to be genotoxic under the conditions of any of the assays described above. Copyright 1999 Academic Press.

Adhesion of Plasmodium falciparum infected erythrocytes in ex vivo perfused placental tissue

DEFF Research Database (Denmark)

Pehrson, Caroline; Mathiesen, Line; Heno, Kristine K

2016-01-01

placental tissue. RESULTS: The ex vivo placental perfusion model was modified to study adhesion of infected erythrocytes binding to CSA, endothelial protein C receptor (EPCR) or a transgenic parasite where P. falciparum erythrocyte membrane protein 1 expression had been shut down. Infected erythrocytes......, such as binding to immunoglobulins. Furthermore, other parasite antigens have been associated with placental malaria. These findings have important implications for placental malaria vaccine design. The objective of this study was to adapt and describe a biologically relevant model of parasite adhesion in intact...... expressing VAR2CSA accumulated in perfused placental tissue whereas the EPCR binding and the transgenic parasite did not. Soluble CSA and antibodies specific against VAR2CSA inhibited binding of infected erythrocytes. CONCLUSION: The ex vivo model provides a novel way of studying receptor-ligand interactions...

Human erythrocytes and neuroblastoma cells are affected in vitro by Au(III) ions

International Nuclear Information System (INIS)

Suwalsky, Mario; Gonzalez, Raquel; Villena, Fernando; Aguilar, Luis F.; Sotomayor, Carlos P.; Bolognin, Silvia; Zatta, Paolo

2010-01-01

Gold compounds are well known for their neurological and nephrotoxic implications. However, haematological toxicity is one of the most serious toxic and less studied effects. The lack of information on these aspects of Au(III) prompted us to study the structural effects induced on cell membranes, particularly that of human erythrocytes. AuCl 3 was incubated with intact erythrocytes, isolated unsealed human erythrocyte membranes (IUM) and molecular models of the erythrocyte membrane. The latter consisted of multibilayers of dimyristoylphosphatidylcholine and dimyristoylphosphatidylethanolamine, phospholipids classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. This report presents evidence that Au(III) interacts with red cell membranes as follows: (a) in scanning electron microscopy studies on human erythrocytes it was observed that Au(III) induced shape changes at a concentration as low as 0.01 μM; (b) in isolated unsealed human erythrocyte membranes Au(III) induced a decrease in the molecular dynamics and/or water content at the glycerol backbone level of the lipid bilayer polar groups in a 5-50 μM concentration range, and (c) X-ray diffraction studies showed that Au(III) in the 10 μm-1 mM range induced increasing structural perturbation only to dimyristoylphosphatidylcholine bilayers. Additional experiments were performed in human neuroblastoma cells SH-SY5Y. A statistically significant decrease of cell viability was observed with Au(III) ranging from 0.1 μM to 100 μM.

Lack of Aquaporin 3 in bovine erythrocyte membranes correlates with low glycerol permeation.

Science.gov (United States)

Campos, Elisa; Moura, Teresa F; Oliva, Abel; Leandro, Paula; Soveral, Graça

2011-05-13

In general, erythrocytes are highly permeable to water, urea and glycerol. However, expression of aquaporin isoforms in erythrocytes appears to be species characteristic. In the present study, human (hRBC) and bovine (bRBC) erythrocytes were chosen for comparative studies due to their significant difference in membrane glycerol permeability. Osmotic water permeability (P(f)) at 23°C was (2.89 ± 0.37) × 10(-2) and (5.12 ± 0.61) × 10(-2)cms(-1) for human and bovine cells, respectively, with similar activation energies for water transport. Glycerol permeability (P(gly)) for human ((1.37 ± 0.26) × 10(-5)cms(-1)) differed in three orders of magnitude from bovine erythrocytes ((5.82 ± 0.37) × 10(-8)cms(-1)) that also showed higher activation energy for glycerol transport. When compared to human, bovine erythrocytes showed a similar expression pattern of AQP1 glycosylated forms on immunoblot analysis, though in slight higher levels, which could be correlated with the 1.5-fold larger P(f) found. However, AQP3 expression was not detectable. Immunofluorescence analysis confirmed the absence of AQP3 expression in bovine erythrocyte membranes. In conclusion, lack of AQP3 in bovine erythrocytes points to the lipid pathway as responsible for glycerol permeation and explains the low glycerol permeability and high E(a) for transport observed in ruminants. Copyright © 2011 Elsevier Inc. All rights reserved.

Magnetic measurements on human erythrocytes: Normal, beta thalassemia major, and sickle

Science.gov (United States)

Sakhnini, Lama

2003-05-01

In this article magnetic measurements were made on human erythrocytes at different hemoglobin states (normal and reduced hemoglobin). Different blood samples: normal, beta thalassemia major, and sickle were studied. Beta thalassemia major and sickle samples were taken from patients receiving lifelong blood transfusion treatment. All samples examined exhibited diamagnetic behavior. Beta thalassemia major and sickle samples showed higher diamagnetic susceptibilities than that for the normal, which was attributed to the increase of membrane to hemoglobin volume ratio of the abnormal cells. Magnetic measurements showed that the erythrocytes in the reduced state showed less diamagnetic response in comparison with erythrocytes in the normal state. Analysis of the paramagnetic component of magnetization curves gave an effective magnetic moment of μeff=7.6 μB per reduced hemoglobin molecule. The same procedure was applied to sickle and beta thalassemia major samples and values for μeff were found to be comparable to that of the normal erythrocytes.

Dielectric response of biconcave erythrocyte membranes to D- and L-Glucose

International Nuclear Information System (INIS)

Livshits, L; Caduff, A; Talary, M S; Feldman, Y

2007-01-01

In this paper, we report on the influence of D- and L-glucose on the dielectric properties of native shaped (biconcave) human erythrocytes using time domain dielectric spectroscopy. The dielectric spectra of biconcave cells were analysed using a modified form of the model originally reported for spheroid particle suspensions (Asami and Yonezawa 1995 Biochim. Biophys. Acta. 1245 317-24) The observed increase in the specific membrane capacitance of the biconcave erythrocytes was correlated with an increase in the concentration of D-glucose. In contrast, no associated correlation was found to changes in the membrane capacitance with increasing concentrations of L-glucose. A similar analysis of the dielectric response of osmotically swollen erythrocytes to changes in D-glucose concentration revealed a significantly different calculated specific cell membrane capacitance at elevated (>12 mM) D-glucose concentrations. The paper outlines and discusses the possible biochemical mechanisms that could be responsible for the measured dielectric properties of the erythrocyte membrane capacitances

Biophysical Properties of Irradiated Erythrocytes and Role of Antioxidants

International Nuclear Information System (INIS)

Eman Mohammed Elbakrawy, E.M.

2010-01-01

Irradiation of blood and blood components with gamma-irradiation is recommended for the inactivation of T-lymphocytes and prevention of transfusion-associated graft versus host diseases. The aim of the present work is to ensure that the currently applied irradiation dose 25 Gy is a safe dose based on the study of the electrical behavior, rheological properties, membrane solubilization, membrane hemolysis and scanning electron microscope of stored erythrocytes. In addition it aims to study the possibility of increasing the irradiation doses to 50 and 100 Gy. Moreover Alpha lipoic acid (a potent natural antioxidant) was added to the stored erythrocytes before irradiation for radioprotection. Irradiation of erythrocytes with 25 Gy did not show significant changes for the calculated dielectric parameters. However, increasing the irradiation doses resulted in significant decrease in the calculated dielectric parameters reflecting the damaging effects of radiation on the membrane structure. The obtained results showed that α lipoic acid can play an important role in minimizing the radiation-induced damage to the erythrocytes and conserve their electrical properties. There were non-significant changes in viscosity after exposure to 25 Gy, while a significant increase at 50 Gy and a significant decrease at 100 Gy were observed. The study found that α lipoic acid (ALA) resulted in non-significant change in viscosity after exposure to 50 Gy and 100 Gy. A significant increase in the yield stress was observed after exposure to 25 and 50 Gy while at 100 Gy, the yield stress showed a remarkable decrease. Addition of .-lipoic acid before irradiation resulted in non-significant changes in the yield stress at doses 25, 50, 100 Gy.The obtained results of the average membrane solubilization (D 50 ) and the average membrane hemolysis (H 50 ) showed non-significant change at 25 Gy; while an observable decrease was observed at 50 Gy and 100 Gy. The addition of lipoic acid did not

Proton NMR studies of creatine in human erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Kuchel, P W; Chapman, B E [Sydney Univ. (Australia). Dept. of Biochemistry

1983-09-01

Proton spin-echo nuclear magnetic resonance spectroscopy was used to measure the relative levels of some metabolites in intact human erythrocytes that had been fractionated by density gradient centrifugation. Age dependent changes in the concentrations of free glycine, choline and ergothioneine were seen for the first time, while glutathione was essentially invariant. In addition, there was a 10-fold decrease in creatine levels from the youngest to oldest cells. This confirms earlier reports and provides a simple explanation for the variable creatine resonance intensities seen in spectra obtained from different erythrocyte samples prepared from the same donor. The different chemical shifts of the methylene resonances of creatine and creatine phosphate was demonstrated and hence confirmed that the bulk of the creatine in intact erythrocytes is not phosphorylated. The chemical shift difference enabled the monitoring of the creatine phosphokinase catalysed reaction in lysates to which the rabbit muscle enzyme had been added. This experiment indicated that the enzyme is not significantly inhibited by factors in the lysates, and introduced a new means of assaying the in situ activity of the enzyme.

Proton NMR studies of creatine in human erythrocytes

International Nuclear Information System (INIS)

Kuchel, P.W.; Chapman, B.E.

1983-01-01

Proton spin-echo nuclear magnetic resonance spectroscopy was used to measure the relative levels of some metabolites in intact human erythrocytes that had been fractionated by density gradient centrifugation. Age dependent changes in the concentrations of free glycine, choline and ergothioneine were seen for the first time, while glutathione was essentially invariant. In addition, there was a 10-fold decrease in creatine levels from the youngest to oldest cells. This confirms earlier reports and provides a simple explanation for the variable creatine resonance intensities seen in spectra obtained from different erythrocyte samples prepared from the same donor. The different chemical shifts of the methylene resonances of creatine and creatine phosphate was demonstrated and hence confirmed that the bulk of the creatine in intact erythrocytes is not phosphorylated. The chemical shift difference enabled the monitoring of the creatine phosphokinase catalysed reaction in lysates to which the rabbit muscle enzyme had been added. This experiment indicated that the enzyme is not significantly inhibited by factors in the lysates, and introduced a new means of assaying the in situ activity of the enzyme. (author)

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

Directory of Open Access Journals (Sweden)

Qin Yan Zhu

2005-01-01

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

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

Complement and Antibody-Mediated Enhancement of Erythrocyte Invasion by Plasmodium Falciparum

Science.gov (United States)

2016-04-01

Haynes, J.D., Moch , J.K., Smoot, D.S., 2002. Erythrocytic malaria growth or invasion inhibi- tion assays with emphasis on suspension culture GIA... Moch , J.K., Finberg, R.W., Tsokos, G.C., Stoute, J.A., 2010. Complement receptor 1 is a sialic acid-independent erythrocyte receptor of Plasmodium

Determination of somatic mutations in human erythrocytes by cytometry

International Nuclear Information System (INIS)

Jensen, R.H.; Langlois, R.G.; Bigbee, W.L.

1985-01-01

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

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.

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.

Intracellular Erythrocyte Platelet-activating Factor Acetylhydrolase I Inactivates Aspirin in Blood*

Science.gov (United States)

Zhou, Gang; Marathe, Gopal K.; Willard, Belinda; McIntyre, Thomas M.

2011-01-01

Aspirin (acetylsalicylic acid) prophylaxis suppresses major adverse cardiovascular events, but its rapid turnover limits inhibition of platelet cyclooxygenase activity and thrombosis. Despite its importance, the identity of the enzyme(s) that hydrolyzes the acetyl residue of circulating aspirin, which must be an existing enzyme, remains unknown. We find that circulating aspirin was extensively hydrolyzed within erythrocytes, and chromatography indicated these cells contained a single hydrolytic activity. Purification by over 1400-fold and sequencing identified the PAFAH1B2 and PAFAH1B3 subunits of type I platelet-activating factor (PAF) acetylhydrolase, a phospholipase A2 with selectivity for acetyl residues of PAF, as a candidate for aspirin acetylhydrolase. Western blotting showed that catalytic PAFAH1B2 and PAFAH1B3 subunits of the type I enzyme co-migrated with purified erythrocyte aspirin hydrolytic activity. Recombinant PAFAH1B2, but not its family member plasma PAF acetylhydrolase, hydrolyzed aspirin, and PAF competitively inhibited aspirin hydrolysis by purified or recombinant erythrocyte enzymes. Aspirin was hydrolyzed by HEK cells transfected with PAFAH1B2 or PAFAH1B3, and the competitive type I PAF acetylhydrolase inhibitor NaF reduced erythrocyte hydrolysis of aspirin. Exposing aspirin to erythrocytes blocked its ability to inhibit thromboxane A2 synthesis and platelet aggregation. Not all individuals or populations are equally protected by aspirin prophylaxis, the phenomenon of aspirin resistance, and erythrocyte hydrolysis of aspirin varied 3-fold among individuals, which correlated with PAFAH1B2 and not PAFAH1B3. We conclude that intracellular type I PAF acetylhydrolase is the major aspirin hydrolase of human blood. PMID:21844189

Intracellular erythrocyte platelet-activating factor acetylhydrolase I inactivates aspirin in blood.

Science.gov (United States)

Zhou, Gang; Marathe, Gopal K; Willard, Belinda; McIntyre, Thomas M

2011-10-07

Aspirin (acetylsalicylic acid) prophylaxis suppresses major adverse cardiovascular events, but its rapid turnover limits inhibition of platelet cyclooxygenase activity and thrombosis. Despite its importance, the identity of the enzyme(s) that hydrolyzes the acetyl residue of circulating aspirin, which must be an existing enzyme, remains unknown. We find that circulating aspirin was extensively hydrolyzed within erythrocytes, and chromatography indicated these cells contained a single hydrolytic activity. Purification by over 1400-fold and sequencing identified the PAFAH1B2 and PAFAH1B3 subunits of type I platelet-activating factor (PAF) acetylhydrolase, a phospholipase A(2) with selectivity for acetyl residues of PAF, as a candidate for aspirin acetylhydrolase. Western blotting showed that catalytic PAFAH1B2 and PAFAH1B3 subunits of the type I enzyme co-migrated with purified erythrocyte aspirin hydrolytic activity. Recombinant PAFAH1B2, but not its family member plasma PAF acetylhydrolase, hydrolyzed aspirin, and PAF competitively inhibited aspirin hydrolysis by purified or recombinant erythrocyte enzymes. Aspirin was hydrolyzed by HEK cells transfected with PAFAH1B2 or PAFAH1B3, and the competitive type I PAF acetylhydrolase inhibitor NaF reduced erythrocyte hydrolysis of aspirin. Exposing aspirin to erythrocytes blocked its ability to inhibit thromboxane A(2) synthesis and platelet aggregation. Not all individuals or populations are equally protected by aspirin prophylaxis, the phenomenon of aspirin resistance, and erythrocyte hydrolysis of aspirin varied 3-fold among individuals, which correlated with PAFAH1B2 and not PAFAH1B3. We conclude that intracellular type I PAF acetylhydrolase is the major aspirin hydrolase of human blood.

Phenotypic variations in osmotic lysis of Sahel goat erythrocytes in non-ionic glucose media.

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Igbokwe, Nanacha Afifi; Igbokwe, Ikechukwu Onyebuchi

2016-03-01

Erythrocyte osmotic lysis in deionised glucose media is regulated by glucose influx, cation efflux, and changes in cell volume after water diffusion. Transmembrane fluxes may be affected by varied expression of glucose transporter protein and susceptibility of membrane proteins to glucose-induced glycosylation and oxidation in various physiologic states. Variations in haemolysis of Sahel goat erythrocytes after incubation in hyposmotic non-ionic glucose media, associated with sex, age, late pregnancy, and lactation, were investigated. The osmotic fragility curve in glucose media was sigmoidal with erythrocytes from goats in late pregnancy (PRE) or lactation (LAC) or from kid (KGT) or middle-aged (MGT) goats. Non-sigmoidal phenotype occurred in yearlings (YGT) and old (OGT) goats. The composite fragility phenotype for males and non-pregnant dry (NPD) females was non-sigmoidal. Erythrocytes with non-sigmoidal curves were more stable than those with sigmoidal curves because of inflectional shift of the curve to the left. Erythrocytes tended to be more fragile with male than female sex, KGT and MGT than YGT and OGT, and LAC and PRE than NPD. Thus, sex, age, pregnancy, and lactation affected the haemolytic pattern of goat erythrocytes in glucose media. The physiologic state of the goat affected the in vitro interaction of glucose with erythrocytes, causing variations in osmotic stability with variants of fragility phenotype. Variations in the effect of high extracellular glucose concentrations on the functions of membrane-associated glucose transporter, aquaporins, and the cation cotransporter were presumed to be relevant in regulating the physical properties of goat erythrocytes under osmotic stress.

Direct measurement of erythrocyte deformability in diabetes mellitus with a transparent microchannel capillary model and high-speed video camera system.

Science.gov (United States)

Tsukada, K; Sekizuka, E; Oshio, C; Minamitani, H

2001-05-01

To measure erythrocyte deformability in vitro, we made transparent microchannels on a crystal substrate as a capillary model. We observed axisymmetrically deformed erythrocytes and defined a deformation index directly from individual flowing erythrocytes. By appropriate choice of channel width and erythrocyte velocity, we could observe erythrocytes deforming to a parachute-like shape similar to that occurring in capillaries. The flowing erythrocytes magnified 200-fold through microscopy were recorded with an image-intensified high-speed video camera system. The sensitivity of deformability measurement was confirmed by comparing the deformation index in healthy controls with erythrocytes whose membranes were hardened by glutaraldehyde. We confirmed that the crystal microchannel system is a valuable tool for erythrocyte deformability measurement. Microangiopathy is a characteristic complication of diabetes mellitus. A decrease in erythrocyte deformability may be part of the cause of this complication. In order to identify the difference in erythrocyte deformability between control and diabetic erythrocytes, we measured erythrocyte deformability using transparent crystal microchannels and a high-speed video camera system. The deformability of diabetic erythrocytes was indeed measurably lower than that of erythrocytes in healthy controls. This result suggests that impaired deformability in diabetic erythrocytes can cause altered viscosity and increase the shear stress on the microvessel wall. Copyright 2001 Academic Press.

Tirilazad mesylate protects stored erythrocytes against osmotic fragility.

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Epps, D E; Knechtel, T J; Bacznskyj, O; Decker, D; Guido, D M; Buxser, S E; Mathews, W R; Buffenbarger, S L; Lutzke, B S; McCall, J M

1994-12-01

The hypoosmotic lysis curve of freshly collected human erythrocytes is consistent with a single Gaussian error function with a mean of 46.5 +/- 0.25 mM NaCl and a standard deviation of 5.0 +/- 0.4 mM NaCl. After extended storage of RBCs under standard blood bank conditions the lysis curve conforms to the sum of two error functions instead of a possible shift in the mean and a broadening of a single error function. Thus, two distinct sub-populations with different fragilities are present instead of a single, broadly distributed population. One population is identical to the freshly collected erythrocytes, whereas the other population consists of osmotically fragile cells. The rate of generation of the new, osmotically fragile, population of cells was used to probe the hypothesis that lipid peroxidation is responsible for the induction of membrane fragility. If it is so, then the antioxidant, tirilazad mesylate (U-74,006f), should protect against this degradation of stored erythrocytes. We found that tirilazad mesylate, at 17 microM (1.5 mol% with respect to membrane lecithin), retards significantly the formation of the osmotically fragile RBCs. Concomitantly, the concentration of free hemoglobin which accumulates during storage is markedly reduced by the drug. Since the presence of the drug also decreases the amount of F2-isoprostanes formed during the storage period, an antioxidant mechanism must be operative. These results demonstrate that tirilazad mesylate significantly decreases the number of fragile erythrocytes formed during storage in the blood bank.

The effects of erythrocyte deformability upon hematocrit assessed by the conductance method

International Nuclear Information System (INIS)

Hayashi, Yoshihito; Katsumoto, Yoichi; Oshige, Ikuya; Omori, Shinji; Yasuda, Akio; Asami, Koji

2009-01-01

A comparative study of centrifugation and conductance methods for the estimation of cell volume fraction (φ) was performed to examine whether the strong forces exerted upon erythrocytes during centrifugation affect their volume, and the results are discussed in terms of erythrocyte deformability. Rabbit erythrocytes of four shapes (spherocytes, echinocytes, stomatocyte-like enlarged erythrocytes and discocytes) were prepared by controlling the pH of the suspending media. The packed cell volumes of the suspensions were measured by standard hematocrit determination methods using centrifugation in capillary tubes. Simultaneously, the same suspensions and their supernatants were used in dielectric spectroscopy measurements, and the low-frequency limits of their conductivities were used for the numerical estimation of φ. The hematocrit values of spherocytes and echinocytes were markedly less than the volume fractions obtained by the conductance method. Namely, the centrifugation reduced the cell volume. For enlarged erythrocytes and discocytes, however, the reduction of cell volume was not observed. These findings showed that φ obtained by the centrifugation method can be greatly affected by the deformability of the cells, but the level of the effect depends on the cell types. Consequently, φ obtained by the centrifugation method should be carefully interpreted.

The effects of erythrocyte deformability upon hematocrit assessed by the conductance method

Energy Technology Data Exchange (ETDEWEB)

Hayashi, Yoshihito; Katsumoto, Yoichi; Oshige, Ikuya; Omori, Shinji; Yasuda, Akio [Life Science Laboratory, Advanced Materials Laboratories, Sony Corporation, Sony Bioinformatics Center, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510 (Japan); Asami, Koji [Laboratory of Molecular Aggregation Analysis, Division of Multidisciplinary Chemistry, Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011 (Japan)], E-mail: Yoshihito.Hayashi@jp.sony.com

2009-04-21

A comparative study of centrifugation and conductance methods for the estimation of cell volume fraction ({phi}) was performed to examine whether the strong forces exerted upon erythrocytes during centrifugation affect their volume, and the results are discussed in terms of erythrocyte deformability. Rabbit erythrocytes of four shapes (spherocytes, echinocytes, stomatocyte-like enlarged erythrocytes and discocytes) were prepared by controlling the pH of the suspending media. The packed cell volumes of the suspensions were measured by standard hematocrit determination methods using centrifugation in capillary tubes. Simultaneously, the same suspensions and their supernatants were used in dielectric spectroscopy measurements, and the low-frequency limits of their conductivities were used for the numerical estimation of {phi}. The hematocrit values of spherocytes and echinocytes were markedly less than the volume fractions obtained by the conductance method. Namely, the centrifugation reduced the cell volume. For enlarged erythrocytes and discocytes, however, the reduction of cell volume was not observed. These findings showed that {phi} obtained by the centrifugation method can be greatly affected by the deformability of the cells, but the level of the effect depends on the cell types. Consequently, {phi} obtained by the centrifugation method should be carefully interpreted.

Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts.

Science.gov (United States)

Bukara, Katarina; Drvenica, Ivana; Ilić, Vesna; Stančić, Ana; Mišić, Danijela; Vasić, Borislav; Gajić, Radoš; Vučetić, Dušan; Kiekens, Filip; Bugarski, Branko

2016-12-20

The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process. Copyright © 2016 Elsevier B.V. All rights reserved.

The role of inorganic phosphate in intact human erythrocytes

International Nuclear Information System (INIS)

Nishiguchi, Eiko; Umeda, Masahiro.

1988-01-01

The role of inorganic phosphate in intact human erythrocytes was investigated by phosphorus-31 nuclear magnetic resonance ( 31 P NMR). When erythrocytes stored for 5 weeks were incubated at 37 deg C, pH 7.4, in medium containing 2 mM adenine and 10 mM inosine, with or without 5 mM glucose, a substance of around 4 ppm, as assessed by 31 P NMR chemical shift, was detected in the mixture. However, this substance disappeared by the addition of inorganic phosphate. When erythrocytes stored for 4 weeks in acid citrate dextrose (ACD) solution were incubated with 2 mM adenine, 10 mM inosine, 5 mM glucose, 50 mM inorganic phosphate and 10 mM pyruvate at 37 deg C, pH 7.4, the 2,3-DPG level increased gradually, whereas the ATP level initially increased and then decreased. Intracellular inorganic phosphate appeared to be used for the synthesis of ATP and 2,3-DPG during the first 30 min. of the reaction. These results suggests that the inorganic phosphate accelerates glycolysis by increasing the activity of glycolytic enzymes rather than its direct involvement in synthesizing organic phosphorus compounds in stored erythrocytes. The results also suggests that the reserve energy from ATP synthesis is not sufficient for the synthesis of 2,3-DPG. (author)

The radioprotective effects of Noni (Morinda citrifolia L.) juice on the bone marrow of irradiated Mus musculus L

International Nuclear Information System (INIS)

Boquiren, Ryan Albert Leonard N.; Te Tan, Alvin E.

2000-03-01

The radioprotective effects of Noni juice on the bone marrow of irradiated Mus musculus L. (7-week old IRC strain) was studied using the micronucleus test. Five mice were used for each of the six groups; negative and positive control, 25%, 50%, 75%, 100% treatment. Both negative and positive control groups were not treated with Noni juice. However, the negative control was not irradiated. Four different concentrations, a mixture of distilled water and commercial Noni juice, were administered via oral gavage to mice in their specific groups during the 15-day feeding schedule. A day (24H) after the last treatment, the mice were irradiated (6 Gy of gamma radiation). Two days (48H) after irradiation, the mice were sacrifice and the femur were extracted. The bone marrow cells were collected and slides were prepared. One thousand polychromatic erythrocytes (PCE) were screened for the presence of micronucleus per mouse. The mean frequency of micronucleated PCE were as follows: negative control, 15; positive control, 45; 25% treatment, 21; 50% treatment, 18; 75% treatment, 11; 100% treatment, 7. The Kruskal-Wallis test showed that the groups' responses varied (α=0.05). Multiple comparison showed that there were significant differences between: (1) 25% and 100% treatment group; (2) positive control group and 75% treatment group; (3) positive control group and 100% treatment group, thus indicating that Noni juice is effective in inhibiting micronucleus formation at high concentrations. The result also showed that radioprotective potential of Noni juice follows a dose-dependent pattern. (Author)

The radioprotective effects of Noni (Morinda citrifolia L.) juice on the bone marrow of irradiated Mus musculus L

Energy Technology Data Exchange (ETDEWEB)

Boquiren, Ryan Albert Leonard N.; Te Tan, Alvin E

2000-03-01

The radioprotective effects of Noni juice on the bone marrow of irradiated Mus musculus L. (7-week old IRC strain) was studied using the micronucleus test. Five mice were used for each of the six groups; negative and positive control, 25%, 50%, 75%, 100% treatment. Both negative and positive control groups were not treated with Noni juice. However, the negative control was not irradiated. Four different concentrations, a mixture of distilled water and commercial Noni juice, were administered via oral gavage to mice in their specific groups during the 15-day feeding schedule. A day (24H) after the last treatment, the mice were irradiated (6 Gy of gamma radiation). Two days (48H) after irradiation, the mice were sacrifice and the femur were extracted. The bone marrow cells were collected and slides were prepared. One thousand polychromatic erythrocytes (PCE) were screened for the presence of micronucleus per mouse. The mean frequency of micronucleated PCE were as follows: negative control, 15; positive control, 45; 25% treatment, 21; 50% treatment, 18; 75% treatment, 11; 100% treatment, 7. The Kruskal-Wallis test showed that the groups' responses varied ({alpha}=0.05). Multiple comparison showed that there were significant differences between: (1) 25% and 100% treatment group; (2) positive control group and 75% treatment group; (3) positive control group and 100% treatment group, thus indicating that Noni juice is effective in inhibiting micronucleus formation at high concentrations. The result also showed that radioprotective potential of Noni juice follows a dose-dependent pattern. (Author)

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

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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.

Fluorescence-based rapid measurement of sphingosine-1-phosphate transport activity in erythrocytes[S

Science.gov (United States)

Kobayashi, Naoki; Otsuka, Masato; Yamaguchi, Akihito; Nishi, Tsuyoshi

2016-01-01

Sphingosine-1-phosphate (S1P) is present in the blood plasma and acts as a pivotal intercellular signal transmitter in the immune system by recruiting lymphocytes from the thymus and secondary lymphoid tissues. The plasma S1P concentration is maintained by the supply of S1P from erythrocytes. Previously, we showed that S1P release from erythrocytes is mediated by an ATP-dependent transporter. In this study, we attempted to establish a rapid and reliable method for measuring the S1P transport activity in erythrocytes by using a fluorescent S1P analog, 7-nitro-2-1,3-benzoxadiazol-4-yl (NBD)-labeled S1P. NBD-S1P was released from erythrocytes in a time-dependent manner. The NBD-S1P release was reduced after exposure to glyburide, which is an inhibitor of the S1P transporter in erythrocytes. Moreover, the release of NBD-S1P and S1P from erythrocytes was competitively inhibited by intracellular S1P and NBD-S1P, respectively. These results showed that the erythrocyte S1P transporter exports NBD-S1P. We optimized the sample-preparation conditions and lipid extraction to increase the sensitivity of the assay. Furthermore, we successfully measured NBD-S1P release without lipid extraction by decreasing the concentration of BSA in the assay buffer to 0.1%. This method will be useful for the high-throughput screening of S1P transporter inhibitors using conventional fluorometers. PMID:27655910

Erythrocyte stiffness during morphological remodeling induced by carbon ion radiation.

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Baoping Zhang

Full Text Available 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

The role of primary lymphoid organs of chickens in the elimination of 51Cr-labelled erythrocytes

International Nuclear Information System (INIS)

Hala, K.; Schulmannova, J.; Nemeckova, S.

1980-01-01

F 1 chicken hybrids of the inbred lines CC and IC were injected erythrocytes from CB line chickens (differing in alloantigens of the major histocompatibility system B) or IA line chickens (differing in the A blood group system alloantigens). Injected erythrocytes were labelled with 51 Cr and their gradual elimination from the recipient's circulation was checked. Surgical bursectomy was performed at the end of embryogenesis and thymectomy immediately after hatching. Bursectomy prolonged the survival of B- and A-incompatible erythrocytes. Thymectomy prolonged the survival of A-incompatible erythrocytes and had no effect on the elimination of erythrocytes possessing B antigens. (author)

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.

Erythrocyte membrane stabilization effect and antioxidant activity of methyl methacrylate

International Nuclear Information System (INIS)

Popov, B.

2004-01-01

Methyl methacrylate (MMK) is a synthetic product with mild impact on human health that is not well studied on cellular basis. Here, human erythrocytes were used to investigate the effects MMK exerts on acid and heat-induced hemolysis. Biphasic effect of MMK was observed for acid-induced hemolysis; i.e., protection at low (0 - 0.05% v/v) and stimulation at higher (0.1- 0.4% v/v) concentrations. The maximal protective effect was produced at 0.03% (v/v). At this concentration MMK increased the temperatures of heat denaturation of erythrocyte membrane proteins, spectrin and integral proteins, by about 2 0 C and inhibited the heat-induced hemolysis by 20 %. This membrane stabilization effect of MMK is similar to that produced by some anti-inflammatory and antirheumatic drugs. The increased acid resistance possibly indicated anti-oxidant properties of MMK. The nonenzymatic antioxidant activity test evidenced that MMK has no superoxide dismutase-like activity but demonstrates strong catalase-like activity (about 900 kU/mmol at 0.05-0.1 mmol/l concentration). The results indicate that at low concentration MMK exerts benign effect on cellular membrane that could find therapeutic usage. (author)

Nutrition and Reproductive Health: Sperm versus Erythrocyte Lipidomic Profile and ω-3 Intake

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Gabriela Ruth Mendeluk

2015-01-01

Full Text Available 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 antioxidants was then performed for 3 months, with the follow-up of both erythrocyte and sperm cell membranes composition as well as conventional sperm parameters. Some significant changes were found in the lipidomic membrane profile of erythrocyte but not in sperm cells, which correspondently did not show significant parameter ameliorations. This is the first report indicating that membrane lipids of different tissues do not equally metabolize the fatty acid elements upon supplementation. Molecular diagnostic tools are necessary to understand the cell metabolic turnover and monitor the success of nutraceuticals for personalized treatments.

Examination of the calcium-erythrocyte membrane interactions

International Nuclear Information System (INIS)

Gardos, Gy.; Szasz, I.; Sarkadi, B.

1979-01-01

A review of the cation-transport mechanisms of human erythrocytes is given. The following experimental methods were applied: measurement of 45 Ca influx, 45 Ca efflux, 42 K influx, 42 K efflux, 22 Na efflux and determination of the activity of the Ca-ATP-ase enzyme. The increase of the intracellular Ca-level opens some specific K-channels, through which K is leaking out passively. The kinetics and the chemical nature of this K-transport are given in detail. On the other hand, Ca ions taken up are removed by active transport. Detailed data are given on the activity and specific inhibition of this Ca-pump. In human erythrocytes the pump is working with the stoichiometry of Ca:ATP=2. (L.E.)

Inhibitin: a specific inhibitor of sodium/sodium exchange in erythrocytes.

OpenAIRE

Morgan, K; Brown, R C; Spurlock, G; Southgate, K; Mir, M A

1986-01-01

An inhibitor of ouabain-insensitive sodium/sodium exchange in erythrocytes has been isolated from leukemic promyelocytes. To explore the specific effects of this inhibitor, named inhibitin, sodium transport experiments were carried out in human erythrocytes. Inhibitin reduced ouabain-insensitive bidirectional sodium transport. It did not change net sodium fluxes, had no significant effect on rubidium influx, and did not inhibit sodium-potassium-ATPase activity. The inhibitory effect of inhibi...

Biomonitoring air quality during and after a public transportation strike in the center of Uberlândia, Minas Gerais, Brazil by Tradescantia micronucleus bioassay.

Science.gov (United States)

Pereira, Boscolli Barbosa; de Campos, Edimar Olegário; de Lima, Euclides Antônio Pereira; Barrozo, Marcos Antonio Souza; Morelli, Sandra

2014-03-01

The aim of this study was to address the lack of information concerning the air quality in the city of Uberlândia, Minas Gerais, Brazil. In this study, we conducted an unprecedented experiment involving the in situ biomonitoring of air genotoxicity in the city center during and after a public transportation strike using the Tradescantia micronucleus test. The frequency of micronuclei was significantly higher in the city center compared with the reference site (Mann-Whitney test, p transport stoppage (Kruskal-Wallis, Dunn p transport stoppage and the increase in the concentration of particulate matter from the increased flow of vehicles in the city center during the strike positively influenced the MN frequency. The climatic factors did not change during the biomonitoring period, reflecting the fact that climatic factors did not influence the MN frequency.

Sickle erythrocytes enhance phenylephrine and histamine ...

African Journals Online (AJOL)

Sickle erythrocytes enhance phenylephrine and histamine contractions of isolated rabbit carotid arteries. ... enhancement of histamine contractions, compared with phenylephrine (in AS and SS), suggests a possible role for histamine in the increased vascular tone and vaso-occlusive crisis in sickle cell disease.

THE NANOSTRUCTURE OF ERYTHROCYTE MEMBRANES UNDER BLOOD INTOXICATION: AN ATOMIC FORCE MICROSCOPY STUDY

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V. A. Sergunova

2016-01-01

Full Text Available Background: The effects of toxins on nanostructure of blood cells are one of the key problems of biophysics and medicine. Erythrocyte morphology and membrane structure are recognized as the main parameters of blood quality. Therefore, analysis of membrane defects under toxin effects seems an urgent issue. Aim: To identify characteristic features and patterns of changes in membrane nanostructure under hemin intoxication and during extended storage of erythrocyte suspension. Materials and methods: The study was done in vitro in human whole blood with addition of hemin, аnd in erythrocyte suspension with a CPD blood preservative stored at 4 °С for 30 days. The nanostructure of erythrocyte membrane was assessed by atomic force microscopy. Results: Characteristic size of space periods between “granules” was from 120 to 200 nm. “Granule” numbers within a topological defect varied from 4 to 5 and to several dozens. Such domains arose virtually on all cells in erythrocyte suspension, as well as after hemin addition to the blood. An increase in hemin intoxication and an increase in a storage time were associated by increases in echinocyte numbers that subsequently transformed into spherical echinocytes. Both under hemin and during the storage of erythrocyte suspension for 9 to 12 days, a specific abnormality in nanostructure of erythrocyte membrane was observed: structural clusters, i.e., domains with granular structure, were formed. Conclusion: The experiments showed that both hemin and oxidative processes in the blood can specifically affect the nanostructure of erythrocyte membranes with formation of domains on their surface. The specific size of granular structures in the domains is from 100 to 200 nm that coincides with a  specific size of spectrin matrix. These results can be used in basic and applied medicine, in blood transfusion, for the analysis of a toxin effects in the human body. The biophysical mechanisms of domain

Effects of phenylpropanolamine (PPA) on in vitro human erythrocyte membranes and molecular models

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Suwalsky, Mario, E-mail: msuwalsk@udec.cl [Faculty of Chemical Sciences, University of Concepcion, Concepcion (Chile); Zambrano, Pablo; Mennickent, Sigrid [Faculty of Pharmacy, University of Concepcion, Concepcion (Chile); Villena, Fernando [Faculty of Biological Sciences, University of Concepcion, Concepcion (Chile); Sotomayor, Carlos P.; Aguilar, Luis F. [Instituto de Quimica, Pontificia Universidad Catolica de Valparaiso, Valparaiso (Chile); Bolognin, Silvia [CNR-Institute for Biomedical Technologies, University of Padova, Padova (Italy)

2011-03-18

Research highlights: {yields} PPA is a common ingredient in cough-cold medication and appetite suppressants. {yields} Reports on its effects on human erythrocytes are very scarce. {yields} We found that PPA induced in vitro morphological changes to human erythrocytes. {yields} PPA interacted with isolated unsealed human erythrocyte membranes. {yields} PPA interacted with class of lipid present in the erythrocyte membrane outer monolayer. -- Abstract: Norephedrine, also called phenylpropanolamine (PPA), is a synthetic form of the ephedrine alkaloid. After reports of the occurrence of intracranial hemorrhage and other adverse effects, including several deaths, PPA is no longer sold in USA and Canada. Despite the extensive information about PPA toxicity, reports on its effects on cell membranes are scarce. With the aim to better understand the molecular mechanisms of the interaction of PPA with cell membranes, ranges of concentrations were incubated with intact human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), and molecular models of cell membranes. The latter consisted in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes present in the outer and inner monolayers of most plasmatic cell membranes, respectively. The capacity of PPA to perturb the bilayer structures of DMPC and DMPE was assessed by X-ray diffraction, DMPC large unilamellar vesicles (LUV) and IUM were studied by fluorescence spectroscopy, and intact human erythrocytes were observed by scanning electron microscopy (SEM). This study presents evidence that PPA affects human red cell membranes as follows: (a) in SEM studies on human erythrocytes it was observed that 0.5 mM PPA induced shape changes; (b) in IUM PPA induced a sharp decrease in the fluorescence anisotropy in the lipid bilayer acyl chains in a concentration range lower than 100 {mu}M; (c) X-ray diffraction studies showed that PPA in the 0.1-0.5 m

Expression of senescent antigen on erythrocytes infected with a knobby variant of the human malaria parasite Plasmodium falciparum

International Nuclear Information System (INIS)

Winograd, E.; Greenan, J.R.T.; Sherman, I.W.

1987-01-01

Erythrocytes infected with a knobby variant of Plasmodium falciparum selectively bind IgG autoantibodies in normal human serum. Quantification of membrane-bound IgG, by use of 125 I-labeled protein A, revealed that erythrocytes infected with the knobby variant bound 30 times more protein A than did noninfected erythrocytes; infection with a knobless variant resulted in less than a 2-fold difference compared with noninfected erythrocytes. IgG binding to knobby erythrocytes appeared to be related to parasite development, since binding of 125 I-labeled protein A to cells bearing young trophozoites (less than 20 hr after parasite invasion) was similar to binding to uninfected erythrocytes. By immunoelectron microscopy, the membrane-bound IgG on erythrocytes infected with the knobby variant was found to be preferentially associated with the protuberances (knobs) of the plasma membrane. The removal of aged or senescent erythrocytes from the peripheral circulation is reported to involve the binding of specific antibodies to an antigen (senescent antigen) related to the major erythrocyte membrane protein band 3. Since affinity-purified autoantibodies against band 3 specifically bound to the plasma membrane of erythrocytes infected with the knobby variant of P. falciparum, it is clear that the malaria parasite induces expression of senescent antigen

Loss of the clock protein PER2 shortens the erythrocyte life span in mice.

Science.gov (United States)

Sun, Qi; Zhao, Yue; Yang, Yunxia; Yang, Xiao; Li, Minghui; Xu, Xi; Wen, Dan; Wang, Junsong; Zhang, Jianfa

2017-07-28

Cell proliferation and release from the bone marrow have been demonstrated to be controlled by circadian rhythms in both humans and mice. However, it is unclear whether local circadian clocks in the bone marrow influence physiological functions and life span of erythrocytes. Here, we report that loss of the clock gene Per2 significantly decreased erythrocyte life span. Mice deficient in Per2 were more susceptible to acute stresses in the erythrocytes, becoming severely anemic upon phenylhydrazine, osmotic, and H 2 O 2 challenges. 1 H NMR-based metabolomics analysis revealed that the Per2 depletion causes significant changes in metabolic profiles of erythrocytes, including increased lactate and decreased ATP levels compared with wild-type mice. The lower ATP levels were associated with hyperfunction of Na + /K + -ATPase activity in Per2 -null erythrocytes, and inhibition of Na + /K + -ATPase activity by ouabain efficiently rescued ATP levels. Per2 -null mice displayed increased levels of Na + /K + -ATPase α1 (ATP1A1) in the erythrocyte membrane, and transfection of Per2 cDNA into the erythroleukemic cell line TF-1 inhibited Atp1a1 expression. Furthermore, we observed that PER2 regulates Atp1a1 transcription through interacting with trans-acting transcription factor 1 (SP1). Our findings reveal that Per2 function in the bone marrow is required for the regulation of life span in circulating erythrocytes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

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.

Effect of complete protein 4.1R deficiency on ion transport properties of murine erythrocytes

International Nuclear Information System (INIS)

Rivera, Alicia; De Franceschi, Lucia; Peters, Luanne L.; Gascard, Philippe; Mohandas, Narla; Brugnara, Carlo

2006-01-01

Moderate hemolytic anemia, abnormal erythrocyte morphology (spherocytosis), and decreased membrane stability are observed in mice with complete deficiency of all erythroid protein 4.1 protein isoforms (4.1-/-; Shi TS et al., J. Clin. Invest. 103:331,1999). We have examined the effects of erythroid protein 4.1 (4.1R) deficiency on erythrocyte cation transport and volume regulation. 4.1-/- mice exhibited erythrocyte dehydration that was associated with reduced cellular K and increased Na content. Increased Na permeability was observed in these mice, mostly mediated by Na/H exchange with normal Na-K pump and Na-K-2Cl cotransport activities. The Na/H exchange of 4.1-/- erythrocytes was markedly activated by exposure to hypertonic conditions (18.2+- 3.2 in 4.1 -/- vs.9.8 +- 1.3 mmol/1013 cell x h in control mice), with an abnormal dependence on osmolarity, (K0.5=417 +- 42 in 4.1 -/- vs. 460 +- 35 mOsmin control mice) suggestive of an up-regulated functional state. While the affinity for internal protons was not altered (K0.5= 489.7 +- 0.7 vs.537.0 +- 0.56 nM in control mice), the Vmax of the H-induced Na/H exchange activity was markedly elevated in 4.1-/- erythrocytes Vmax 91.47 Moderate hemolytic anemia, abnormal erythrocyte morphology (spherocytosis), and decreased membrane stability are observed in mice with complete deficiency of all erythroid protein 4.1 protein isoforms (4.1-/-; Shi TSet al., J. Clin. Invest. 103:331,1999). We have examined the effects of erythroid protein 4.1 (4.1R) deficiency on erythrocyte cation transport and volume regulation. 4.1-/- mice exhibited erythrocyte dehydration that was associated with reduced cellular K and increased Na content. Increased Na permeability was observed in these mice, mostly mediated by Na/H exchange with normal Na-K pump and Na-K-2Cl cotransport activities. The Na/H exchange of 4.1-/- erythrocytes was markedly activated by exposure to hypertonic conditions (18.2 +- 3.2 in 4.1 -/- vs. 9.8 +- 1.3mmol/1013 cell x h in

Monocyte-mediated erythrocyte destruction. A comparative study of current methods

International Nuclear Information System (INIS)

Hunt, J.S.; Beck, M.L.; Wood, G.W.

1981-01-01

Three assay systems-EAIgG rosette formation, 51Cr release, and erythrophagocytosis-were used to quantitate interaction between antibody-coated human erythrocytes and normal blood monocytes. The three methods were compared in terms of time requirements and sensitivity. Erythrophagocytosis required more time to perform (2 hours) than did rosette tests (30 minutes) but less than minimum 51Cr release assays (5.5 hours). Erythrophagocytosis was 20-fold more sensitive than either of the other two procedures. Results obtained with purified IgG anti-D and with antibodies induced by transfusion or pregnancy were similar

High thiamine diphosphate concentrations in erythrocytes can be achieved in dialysis patients by oral administration of benfontiamine.

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Frank, T; Bitsch, R; Maiwald, J; Stein, G

2000-06-01

The influence of either orally administered S-benzoylthiamine-O-monophosphate (benfotiamine) or thiamine nitrate on the thiamine status was tested in a randomised, two-group comparison study in 20 end-stage renal disease (ESRD) patients. Main outcome measures were the pharmacokinetics of thiamine diphosphate (TDP) in blood, the in vitro erythrocyte transketolase activity, its activation coefficient (alpha-ETK) and the TDP concentration in erythrocytes. After ingestion of a single dose of either 100 mg thiamine nitrate (corresponding to 305 micromol thiamine) or 100 mg benfotiamine (corresponding to 214 micromol thiamine), the blood levels of thiamine phosphate esters were analysed by means of high-performance liquid chromatography for a 24-h period. The TDP concentration in erythrocytes was calculated using the haematocrit and TDP concentration in blood. Erythrocyte transketolase activity and alpha-ETK were measured before and 10 h after administration. The pharmacokinetics of TDP in blood were compared with healthy subjects of other studies retrieved from database query. Regarding the blood concentrations of TDP, the patients with ESRD had a 4.3 times higher area under the concentration time curve after benfotiamine administration than after thiamine nitrate. After benfotiamine administration, the peak plasma concentration of TDP exceeded that in healthy subjects by 51%. In the ESRD patients, after 24 h, the mean TDP concentration in erythrocytes increased from 158.7+/-30.9 ng/ml initially to 325.8+/-50.9 ng/ml after administration of benfotiamine and from 166.2+/-51.9 ng/ml to 200.5+/-50.0 ng/ml after thiamine nitrate administration. The ratio between the maximum erythrocyte TDP concentration and basal concentration was 2.66+/-0.6 in the benfotiamine group and 1.44+/-0.2 in the group receiving thiamine nitrate (P benfotiamine intake (P = 0.02) and from 3.71+/-0.8 microkat/l to 4.02+/-0.7 microkat/l after thiamine nitrate intake (P = 0.08). Likewise, alpha

Graphistrength© C100 MultiWalled Carbon Nanotubes (MWCNT): thirteen-week inhalation toxicity study in rats with 13- and 52-week recovery periods combined with comet and micronucleus assays

International Nuclear Information System (INIS)

Régnier, Jean-François; Pothmann-Krings, Daniela; Simar, Sophie; Dony, Eva; Net, Jean-Loïc Le; Beausoleil, Julien

2017-01-01

Graphistrength© C100 provides superior electrical and mechanical properties for various applications and is one of the industrial MWCNT referenced in the OECD sponsorship program for the safety testing of nanomaterials. Graphistrength© C100 is formed of MWCNT (ca. 12 walls, outer mean diameter ca. 12 nm, length ca. 1 µm) agglomerated in particles with a granulometry centered on 400 µm. A general feature of MWCNT after inhalation or intratracheal exposures is the induction of an inflammatory reaction in the lungs sometimes associated with local genotoxic effects. Most of the in vitro and in vivo genotoxicity data available on Graphistrength© C100 are negative. However, a weak DNA damage activity in the in vitro and in vivo FPG-modified Comet assays and a weak clastogenic effect in the in vitr o micronucleus test were reported. After investigating different parameters for the aerosol generation, male and female Wistar rats were exposed by nose-only inhalation (6h/day, 5d/week) to target concentrations of 0.05, 0.25 and 5.0 mg/m 3 air of a respirable aerosol (MMAD < 3 µm) and sacrificed immediately after 4 and 13 weeks of exposure and 13 and 52 weeks of recovery after the 13-week exposure. Clinical, biological and histological evaluations were performed according to the OECD TG 413. Broncho-alveolar lavage fluid (BALF) was collected and analysed for cytokines and inflammatory parameters. Immediately after 13 weeks of exposure, chromosomal aberrations in the bone marrow cells of males and females were evaluated by the micronucleus test (OECD TG 474) and DNA damage in the lung, kidney and liver cells of males were assessed by both the standard and the human 8-oxoguanine DNA N-glycosylase 1 (hOGG1)-modified comet assay (OECD TG 489). Concentration-related deposition of black particles (MWCNT) was observed in lungs. At all sacrifice periods, an inflammatory lung reaction was observed in rats exposed to 5.0 mg/m 3 associated with changes in the differential white

iAB-RBC-283: A proteomically derived knowledge-base of erythrocyte metabolism that can be used to simulate its physiological and patho-physiological states.

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Bordbar, Aarash; Jamshidi, Neema; Palsson, Bernhard O

2011-07-12

The development of high-throughput technologies capable of whole cell measurements of genes, proteins, and metabolites has led to the emergence of systems biology. Integrated analysis of the resulting omic data sets has proved to be hard to achieve. Metabolic network reconstructions enable complex relationships amongst molecular components to be represented formally in a biologically relevant manner while respecting physical constraints. In silico models derived from such reconstructions can then be queried or interrogated through mathematical simulations. Proteomic profiling studies of the mature human erythrocyte have shown more proteins present related to metabolic function than previously thought; however the significance and the causal consequences of these findings have not been explored. Erythrocyte proteomic data was used to reconstruct the most expansive description of erythrocyte metabolism to date, following extensive manual curation, assessment of the literature, and functional testing. The reconstruction contains 281 enzymes representing functions from glycolysis to cofactor and amino acid metabolism. Such a comprehensive view of erythrocyte metabolism implicates the erythrocyte as a potential biomarker for different diseases as well as a 'cell-based' drug-screening tool. The analysis shows that 94 erythrocyte enzymes are implicated in morbid single nucleotide polymorphisms, representing 142 pathologies. In addition, over 230 FDA-approved and experimental pharmaceuticals have enzymatic targets in the erythrocyte. The advancement of proteomic technologies and increased generation of high-throughput proteomic data have created the need for a means to analyze these data in a coherent manner. Network reconstructions provide a systematic means to integrate and analyze proteomic data in a biologically meaning manner. Analysis of the red cell proteome has revealed an unexpected level of complexity in the functional capabilities of human erythrocyte metabolism.

Inhibition by nucleosides of glucose-transport activity in human erythrocytes.

OpenAIRE

Jarvis, S M

1988-01-01

The interaction of nucleosides with the glucose carrier of human erythrocytes was examined by studying the effect of nucleosides on reversible cytochalasin B-binding activity and glucose transport. Adenosine, inosine and thymidine were more potent inhibitors of cytochalasin B binding to human erythrocyte membranes than was D-glucose [IC50 (concentration causing 50% inhibition) values of 10, 24, 28 and 38 mM respectively]. Moreover, low concentrations of thymidine and adenosine inhibited D-glu...

Use of the micronucleus assay for the selective detection of radiosensitivity in BUdR-unincorporated cells after pulse-labelling of exponentially growing tumour cells

Energy Technology Data Exchange (ETDEWEB)

Masunaga, S.; Ono, K.; Fushiki, M.; Abe, M. (Kyoto Univ. (Japan). Faculty of Medicine); Wandl, E.O. (Vienna Univ. (Austria). Klinik fuer Strahlentherapie und Strahlenbiologie)

1990-08-01

To determine the radiosensitivity of non S-phase tumour cells in vitro, survival curves of SCC VII tumour cells were obtained after a short block with hydroxyurea. Dose-response curves of micronucleus (MN) frequency appearing in non-S-phase cells were also determined by excluding S-phase cells with immunofluorescence staining to 5-bromo-2'-deoxyuridine (BUdR). Both the dose response curves of MN frequency and survival curves were analysed by a linear-quadratic model (surviving fraction =exp (-{alpha}D-{beta}D{sup 2}), MN frequency =aD+bD{sup 2}+c). A good correlation between the {alpha}/{beta} and a/b ratios was observed. In both BUdR-unincorporated and asynchronous cell cultures, the regression lines between the surviving fraction and micronucleus frequency were statistically identical. (author).

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.

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

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

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.

Interaction of Plasmodium falciparum knob-associated histidine-rich protein (KAHRP) with erythrocyte ankyrin R is required for its attachment to the erythrocyte membrane.

Science.gov (United States)

Weng, Haibo; Guo, Xinhua; Papoin, Julien; Wang, Jie; Coppel, Ross; Mohandas, Narla; An, Xiuli

2014-01-01

The malaria parasite Plasmodium falciparum exports a large number of proteins into the erythrocyte cytoplasm during the asexual intraerythrocytic stage of its life cycle. A subset of these proteins interacts with erythrocyte membrane skeletal proteins and grossly alters the structure and function of the membrane. Several of the exported proteins, such as PfEMP1, PfEMP3, RESA and KAHRP, interact with the preponderant erythrocyte skeleton protein, spectrin. Here we have searched for possible interaction of these four malaria proteins with another major erythrocyte skeleton protein, ankyrin R. We have shown that KAHRP, but none of the other three, binds to ankyrin R. We have mapped the binding site for ankyrin R to a 79-residue segment of the KAHRP sequence, and the reciprocal binding site for KAHRP in ankyrin R to a subdomain (D3) of the 89kDa ankyrin R membrane-binding domain. Interaction of intact ankyrin R with KAHRP was inhibited by the free D3 subdomain. When, moreover, red cells loaded with the soluble D3 subdomain were infected with P. falciparum, KAHRP secreted by the intraerythrocytic parasite no longer migrated to the host cell membrane, but remained diffusely distributed throughout the cytosol. Our findings suggest a potentially important role for interaction of KAHRP with red cell membrane skeleton in promoting the adhesion of malaria-infected red cells to endothelial surfaces, a central element in the pathophysiology of malaria. © 2013.

Recruitment of human aquaporin 3 to internal membranes in the Plasmodium falciparum infected erythrocyte.

Science.gov (United States)

Bietz, Sven; Montilla, Irine; Külzer, Simone; Przyborski, Jude M; Lingelbach, Klaus

2009-09-01

The molecular mechanisms underlying the formation of the parasitophorous vacuolar membrane in Plasmodium falciparum infected erythrocytes are incompletely understood, and the protein composition of this membrane is still enigmatic. Although the differentiated mammalian erythrocyte lacks the machinery required for endocytosis, some reports have described a localisation of host cell membrane proteins at the parasitophorous vacuolar membrane. Aquaporin 3 is an abundant plasma membrane protein of various cells, including mammalian erythrocytes where it is found in distinct oligomeric states. Here we show that human aquaporin 3 is internalized into infected erythrocytes, presumably during or soon after invasion. It is integrated into the PVM where it is organized in novel oligomeric states which are not found in non-infected cells.

Genotoxicity and ELF-magnetic fields: a review through the micronucleus assay

International Nuclear Information System (INIS)

Alcaraz, M.; Andreu-Galvez, M.; Sanchez-Villalobos, J. M.; Achel, D. G.; Olmos, E.; Martinez-Hernandez, C. M.

2012-01-01

Thirty for (34) published studies, conducted from 1994 to the present to evaluate the genotoxic effect of magnetic fields using ELF-EMF and diagnostic resonance on humans by the micronucleus assay have been reviewed. some characteristics of the assay methods, their significance to genotoxicity and basic interpretations of the results of these assays are discussed. of the studies analysed 70.5% implicated genotoxic effects induced by these magnetic fields: 52.9% were due to exposure to magnetic fields only and 17,6% by exposure to magnetic fields in combination with some treatment types, resulting in additive or synergistic effect. Evidence exist to support the notion that exposure of humans to magnetic fields stimulates genotoxic effects, although the actual mechanisms of action or even the true human health consequences resulting from these exposure still remain unclear. (Author) 80 refs.

The AMP-activated protein kinase beta 1 subunit modulates erythrocyte integrity.

Science.gov (United States)

Cambridge, Emma L; McIntyre, Zoe; Clare, Simon; Arends, Mark J; Goulding, David; Isherwood, Christopher; Caetano, Susana S; Reviriego, Carmen Ballesteros; Swiatkowska, Agnieszka; Kane, Leanne; Harcourt, Katherine; Adams, David J; White, Jacqueline K; Speak, Anneliese O

2017-01-01

Failure to maintain a normal in vivo erythrocyte half-life results in the development of hemolytic anemia. Half-life is affected by numerous factors, including energy balance, electrolyte gradients, reactive oxygen species, and membrane plasticity. The heterotrimeric AMP-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase that acts as a critical regulator of cellular energy balance. Previous roles for the alpha 1 and gamma 1 subunits in the control of erythrocyte survival have been reported. In the work described here, we studied the role of the beta 1 subunit in erythrocytes and observed microcytic anemia with compensatory extramedullary hematopoiesis together with splenomegaly and increased osmotic resistance. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Erythrocyte swelling and membrane hole formation in hypotonic media as studied by conductometry.

Science.gov (United States)

Pribush, A; Meyerstein, D; Hatskelzon, L; Kozlov, V; Levi, I; Meyerstein, N

2013-02-01

Hypoosmotic swelling of erythrocytes and the formation of membrane holes were studied by measuring the dc conductance (G). In accordance with the theoretical predictions, these processes are manifested by a decrease in G followed by its increase. Thus, unlike the conventional osmotic fragility test, the proposed methodological approach allows investigations of both the kinetics of swelling and the erythrocyte fragility. It is shown that the initial rate of swelling and the equilibrium size of the cells are affected by the tonicity of a hypotonic solution and the membrane rheological properties. Because the rupture of biological membranes is a stochastic process, a time-dependent increase in the conductance follows an integral distribution function of the membrane lifetime. The main conclusion which stems from reported results is that information about rheological properties of red blood cell (RBC) membranes and the resistivity of RBCs to a certain osmotic shock may be extracted from conductance signals.

Fecal blood loss in patients with colonic polyps: a comparison of measurements with 51chromium-labeled erythrocytes and with the Haemoccult test

International Nuclear Information System (INIS)

Herzog, P.; Holtermueller, K.H.; Preiss, J.; Fischer, J.; Ewe, K.; Schreiber, H.J.; Berres, M.

1982-01-01

The quantitative determinations of fecal daily blood loss after intravenous administration of 51 Cr-labeled erythrocytes in 44 patients with colonic polyps and in 11 controls were compared with the results of the daily performed Haemoccult test without dietary restrictions. A total of 642 stool specimens was analyzed for 51 Cr loss and the Haemoccult test. The mean fecal daily blood loss in the 34 patients with adenomatous polyps of the descending colon and rectosigmoid was 1.36 +/- 0.14 ml/day (mean +/- SEM), in the 10 patients with polyps of the ascending and transverse colon it was 1.28 +/- 0.31 ml/day, and in the 11 controls 0.62 +/- 0.07 ml/day. There was no positive Haemoccult test in the controls. In fecal specimens from patients with polyps in the descending colon and rectosigmoid containing 2.0-3.99 ml blood/day, the Haemoccult-test was positive in 86%. Fecal specimens from patients with polyps in the ascending colon and transverse colon containing equal blood loss yielded a positive Haemoccult test result in 26%. Thus, the positivity of the Haemoccult test is determined by the fecal daily blood loss and the anatomic location of colonic bleeding sites

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.

Test of micronucleus in lymphocytes with the cytokinesis-block like possible indicator of the answer of the patient to the radiotherapy; Ensayo de micronucleos en linfocitos con bloqueo de la citocinesis como posible indicador de la respuesta del paciente a la radioterapia

Energy Technology Data Exchange (ETDEWEB)

Giorgio, Marina di; Nasazzi, Nora; Taja, Maria R. [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); Roth, Berta [Instituto de Oncologia Angel H. Roffo, Buenos Aires (Argentina); Sardi, Mabel; Menendez, Pablo R. [Hospital Italiano, Buenos Aires (Argentina)

2001-07-01

In order to evaluate the individual cytogenetic response to radiotherapy and its comparison with the clinical response, the cytokinesis-block micronucleus assay was applied to peripheral blood lymphocytes of patients with cervix cancer undergoing radiotherapy. The cytogenetic data were analysed using a mathematical model to evaluate the attenuation of the cytogenetic effect as a function of the time between a single exposure and blood sampling, estimating a cytogenetic recovery factor (k) that might correlate with the individual radiosensitivity, contributing with radiosensitivity tests of current use but applying a rapid methodology easy to implement in a routine clinical laboratory. Long term clinical observations could confirm the validity of k in expressing predisposition of the subject to develop delayed effects. (author)

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.

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.

Alcohol and the calcium-dependent potassium transport of human erythrocytes

International Nuclear Information System (INIS)

Harris, R.A.; Caldwell, K.K.

1985-01-01

In vitro exposure of human red blood cells to ethanol (100 and 400 mM) was found to increase the initial rate of calcium-dependent potassium efflux through the red cell membrane. This effect of ethanol was apparently not due to an elevation of the intracellular free calcium but rather to a direct action of the drug on the transport process as, (1) intracellular calcium concentrations were tightly buffered with EGTA, (2) ethanol did not alter the efflux of 45 Ca from the cells, and (3) dantrolene, which has been proposed to counteract the effect of ethanol on intracellular calcium levels in the erythrocyte, did not inhibit the stimulatory action of ethanol. The efflux of potassium from erythrocytes obtained from chronic alcoholics was not different from that of erythrocytes from non-alcoholic individuals. The relationship of these findings to neuronal potassium transport is discussed

An evaluation of the genotoxic and cytotoxic effects of the anti-obesity drugs sibutramine and fenproporex.

Science.gov (United States)

da Silva, Cristiano José; dos Santos, José Ernesto; Satie Takahashi, Catarina

2010-03-01

Anti-obesity medications deserve special considerations at the present time due to an increasing number of overweight and obese people who require these therapeutic alternatives. Obesity is positively associated with several chronic illnesses, including cancer. In this work, we evaluated the possible genotoxic and/or cytotoxic actions of two drugs, sibutramine and fenproporex, in the doses of 10, 20 and 40 mg/kg body weight (bw), administered intraperitoneally in male Swiss mice. The genotoxic effect was analyzed by comet assay and micronucleus test. We found that both drugs increased the frequency of genotoxic damage in Swiss mice, but did not present cytotoxic activities towards the polychromatic erythrocytes of the bone marrow of these animals.

Transport of 3-bromopyruvate across the human erythrocyte membrane.

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Sadowska-Bartosz, Izabela; Soszyński, Mirosław; Ułaszewski, Stanisław; Ko, Young; Bartosz, Grzegorz

2014-06-01

3-Bromopyruvic acid (3-BP) is a promising anticancer compound because it is a strong inhibitor of glycolytic enzymes, especially glyceraldehyde 3-phosphate dehydrogenase. The Warburg effect means that malignant cells are much more dependent on glycolysis than normal cells. Potential complications of anticancer therapy with 3-BP are side effects due to its interaction with normal cells, especially erythrocytes. Transport into cells is critical for 3-BP to have intracellular effects. The aim of our study was the kinetic characterization of 3-BP transport into human erythrocytes. 3-BP uptake by erythrocytes was linear within the first 3 min and pH-dependent. The transport rate decreased with increasing pH in the range of 6.0-8.0. The Km and Vm values for 3-BP transport were 0.89 mM and 0.94 mmol/(l cells x min), respectively. The transport was inhibited competitively by pyruvate and significantly inhibited by DIDS, SITS, and 1-cyano-4-hydroxycinnamic acid. Flavonoids also inhibited 3-BP transport: the most potent inhibition was found for luteolin and quercetin.

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.

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.

Sickle erythrocytes enhance phenylephrine and histamine

African Journals Online (AJOL)

Dr Olaleye

the influence of sickle erythrocyte on contractile responses induced by phenylephrine and histamine. ... obtained from subjects of different haemoglobin (Hb) genotypes (AA, AS and SS), under ... the sixth position of the β-chain of the hemoglobin S. Address for ... blood pressure values in sickle cell anaemia subjects as.

Enzymatic methylation of band 3 anion transporter in intact human erythrocytes

International Nuclear Information System (INIS)

Lou, L.L.; Clarke, S.

1987-01-01

Band 3, the anion transport protein of erythrocyte membranes, is a major methyl-accepting substrate of the intracellular erythrocyte protein carboxyl methyltransferase (S-adenosyl-L-methionine: protein-D-aspartate O-methyltransferase; EC 2.1.1.77). The localization of methylation sites in intact cells by analysis of proteolytic fragments indicated that sites were present in the cytoplasmic N-terminal domain as well as the membranous C-terminal portion of the polypeptide. The amino acid residues that serve as carboxyl methylation sites of the erythrocyte anion transporter were also investigated. 3 H-Methylated band 3 was purified from intact erythrocytes incubated with L-[methyl- 3 H]methionine and from trypsinized and lysed erythrocytes incubated with S-adenosyl-L-[methyl- 3 H]methionine. After proteolytic digestion with carboxypeptidase Y, D-aspartic acid beta-[ 3 H]methyl ester was isolated in low yields (9% and 1%, respectively) from each preparation. The bulk of the radioactivity was recovered as [ 3 H]methanol, and the amino acid residue(s) originally associated with these methyl groups could not be determined. No L-aspartic acid beta-[ 3 H]methyl ester or glutamyl gamma-[ 3 H]methyl ester was detected. The formation of D-aspartic acid beta-[ 3 H]methyl esters in this protein in intact cells resulted from protein carboxyl methyltransferase activity since it was inhibited by adenosine and homocysteine thiolactone, which increases the intracellular concentration of the potent product inhibitor S-adenosylhomocysteine, and cycloleucine, which prevents the formation of the substrate S-adenosyl-L-[methyl- 3 H]methionine

[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.

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

OpenAIRE

Matteucci, Elena; Giampietro, Ottavio

2007-01-01

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 dama...

iAB-RBC-283: A proteomically derived knowledge-base of erythrocyte metabolism that can be used to simulate its physiological and patho-physiological states

Directory of Open Access Journals (Sweden)

Palsson Bernhard O

2011-07-01

Full Text Available Abstract Background The development of high-throughput technologies capable of whole cell measurements of genes, proteins, and metabolites has led to the emergence of systems biology. Integrated analysis of the resulting omic data sets has proved to be hard to achieve. Metabolic network reconstructions enable complex relationships amongst molecular components to be represented formally in a biologically relevant manner while respecting physical constraints. In silico models derived from such reconstructions can then be queried or interrogated through mathematical simulations. Proteomic profiling studies of the mature human erythrocyte have shown more proteins present related to metabolic function than previously thought; however the significance and the causal consequences of these findings have not been explored. Results Erythrocyte proteomic data was used to reconstruct the most expansive description of erythrocyte metabolism to date, following extensive manual curation, assessment of the literature, and functional testing. The reconstruction contains 281 enzymes representing functions from glycolysis to cofactor and amino acid metabolism. Such a comprehensive view of erythrocyte metabolism implicates the erythrocyte as a potential biomarker for different diseases as well as a 'cell-based' drug-screening tool. The analysis shows that 94 erythrocyte enzymes are implicated in morbid single nucleotide polymorphisms, representing 142 pathologies. In addition, over 230 FDA-approved and experimental pharmaceuticals have enzymatic targets in the erythrocyte. Conclusion The advancement of proteomic technologies and increased generation of high-throughput proteomic data have created the need for a means to analyze these data in a coherent manner. Network reconstructions provide a systematic means to integrate and analyze proteomic data in a biologically meaning manner. Analysis of the red cell proteome has revealed an unexpected level of complexity in

Application of liquid-based cytology preparation in micronucleus assay of exfoliated buccal epithelial cells in road construction workers.

Science.gov (United States)

Arul, P

2017-01-01

Asphalts are bitumens that consist of complex of hydrocarbon mixtures and it is used mainly in road construction and maintenance. This study was undertaken to evaluate the micronucleus (MN) assay of exfoliated buccal epithelial cells in road construction workers using liquid-based cytology (LBC) preparation. Three different stains (May-Grunwald Giemsa, hematoxylin and eosin, and Papanicolaou) were used to evaluate the frequency of MN in exfoliated buccal epithelial of 100 participants (fifty road construction workers and fifty administrative staff) using LBC preparation. Statistical analysis was performed with Student's t-test, and Proad construction exhibit a higher frequency of MN in exfoliated buccal epithelial cells and they are under the significant risk of cytogenetic damage. LBC preparation has potential application for the evaluation of frequency of MN. This technique may be advocated in those who are occupationally exposed to potentially carcinogenic agents in view of improvement in the smear quality and visualization of cell morphology.

An antimutagenic monoterpene from Malachra fasciata (Malvaveae)

International Nuclear Information System (INIS)

Ragasa, Consolacion Y.; Agbayani, Virgilio; Hernandez, Reynan B.; Rideout, John A.

1997-01-01

A monoterpene was isolated from the leaves of Malachra fasciata by gravity column chromatography. Its structure was elucidated by extensive1D and 2D NMR spectroscopy. It was identified as loliolide by comparison of its 1 H and 1 3 C NMR spectral data with those found in the literature. The compound was tested for its antimutagenicity potential by the use of the micronucleus test. Results of the study indicated a 64.4% reduction in micronucleated polychromatic erythrocytes induced by mitomycin C, when loliolide at a dosage of 14.8 mg/kg was administered to mice of the Swiss strain. Another isolate from the leaves of the plant was stigmasterol which structure was determined by comparison of its 1 H NMR spectal data with those found in the literature. (Author)

Erythrocyte Saturation with IgG Is Required for Inducing Antibody-Mediated Immune Suppression and Impacts Both Erythrocyte Clearance and Antigen-Modulation Mechanisms.

Science.gov (United States)

Cruz-Leal, Yoelys; Marjoram, Danielle; Lazarus, Alan H

2018-02-15

Anti-D prevents hemolytic disease of the fetus and newborn, and this mechanism has been referred to as Ab-mediated immune suppression (AMIS). Anti-D, as well as other polyclonal AMIS-inducing Abs, most often induce both epitope masking and erythrocyte clearance mechanisms. We have previously observed that some Abs that successfully induce AMIS effects could be split into those that mediate epitope masking versus those that induce erythrocyte clearance, allowing the ability to analyze these mechanisms separately. In addition, AMIS-inducing activity has recently been shown to induce Ag modulation (Ag loss from the erythrocyte surface). To assess these mechanisms, we immunized mice with transgenic murine RBCs expressing a single Ag protein comprising a recombinant Ag composed of hen egg lysozyme, OVA sequences comprising aa 251-349, and the human Duffy transmembrane protein (HOD-Ag) with serial doses of polyclonal anti-OVA IgG as the AMIS-inducing Ab. The anti-OVA Ab induced AMIS in the absence of apparent epitope masking. AMIS occurred only when the erythrocytes appeared saturated with IgG. This Ab was capable of inducing HOD-RBC clearance, as well as loss of the OVA epitope at doses of Ab that caused AMIS effects. HOD-RBCs also lost reactivity with Abs specific for the hen egg lysozyme and Duffy portions of the Ag consistent with the initiation of Ag modulation and/or trogocytosis mechanisms. These data support the concept that an AMIS-inducing Ab that does not cause epitope masking can induce AMIS effects in a manner consistent with RBC clearance and/or Ag modulation. Copyright © 2018 by The American Association of Immunologists, Inc.

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 ...

[Comparative investigation of the non-histone proteins of chromatin from pigeon erythroblasts and erythrocytes].

Science.gov (United States)

Fedina, A B; Gazarian, G G

1976-01-01

Chromosomal non-histone proteins are obtained from nuclei of two types of pigeon erythroid cells: erythroblasts (cells active in RNA synthesis) and erythrocytes (cells with repressed RNA synthesis). They are well soluble in solutions of low ionic strength. Electrophoretic separation of the obtained non-histone proteins in polyacrylamide gels with urea and SDS shows the presence of qualitative differences in the pattern of non-histone proteins of chromatine from erythroblasts and erythrocytes. By electrophoresis in urea some protein bands of non-histone proteins of chromatine from erythroblasts were found which disappear with the aging of cells. At the same time two protein fractions were observed in chromatine from erythrocytes which were absent in that of erythroblasts. Disappearance of some high molecular weight protein fractions from erythrocyte chromatine as compared to erythroblasts was observed by separation of the non-histone proteins in the presence of SDS. These fractions of the non-histone proteins disappearing during aging of cells are well extractable from erythroblast chromatine by 0.35 M NaCl solution. In the in vitro system with E. coli RNA polymerase addition of non-histone proteins of chromatine from erythroblasts to chromatine from erythrocytes increases RNA synthesis 2--3 times. At the same time addition of non-histone proteins from erythrocytes is either without any influence on this process or somewhat inhibiting.

Changes of chromosome aberration rate and micronucleus frequency along with accumulated dose in continuously irradiated mice with a low dose rate of γ-rays

International Nuclear Information System (INIS)

Tanaka, Kimio; Izumi, Jun; Yanai, Takanori; Ichinohe, Kazuaki; Matsumoto, Tsuneya

2003-01-01

Chromosome aberrations in chronically exposed workers in nuclear facilities and medical radiologists have been reported. However chronological change of chromosome aberration rates along with accumulated dose has not been well studied. Chromosome aberrations and micronuclei in spleen lymphocytes were observed serially in mice continuously irradiated with a low dose rate of 20 mGy/day up to 400 days. Chromosome aberration rates were rapidly increased to 11.1% at 1 Gy, while micronucleus incidence increased at 5 Gy. After these doses their increase rates were saturated. Micronucleus incidence in bone marrow erythroblasts was higher than in spleen cells. These chronological changes of cytogenetic aberrations seem to be induced through a balance between developments of chromosome aberrations and micronuclei, and life span of spleen lymphocytes. These results will be helpful for risk assessment in low dose rate radiation exposure. (author)

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.

Effects of centrifugation on transmembrane water loss from normal and pathologic erythrocytes

International Nuclear Information System (INIS)

Kaperonis, A.A.; Chien, S.

1989-01-01

Plasma 125 I-albumin was used as a marker of extracellular dilution in order to study the effect of high-speed centrifugation on transmembrane water distribution in several types of human red cells, including normal (AA), hemoglobin variants (beta A, AS, SC, beta S, and SS), and those from patients with hereditary spherocytosis. SS and AA erythrocytes were also examined for changes in intracellular hemoglobin concentration of three different density fractions and with increasing duration of spin. The minimum force and duration of centrifugation required to impair water permeability were found to vary with the red cell type, the anticoagulant used (heparin or EDTA), the initial hematocrit of the sample centrifuged, as well as among the individual erythrocyte fractions within the same sample. When subjecting pathologic erythrocytes to high-speed centrifugation, the 125 I-albumin dilution technique can be used to determine whether the centrifugation procedure has led to an artifactual red cell water loss and to correct for this when it does occur. An abnormal membrane susceptibility to mechanical stress was demonstrated in erythrocytes from patients with hereditary spherocytosis and several hemoglobinopathies

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.

Age related changes in erythrocyte A and B antigen strength

Energy Technology Data Exchange (ETDEWEB)

Hollingsworth, J W; Hamilton, H B; Ishii, Goro

1961-11-01

The strength of A and B antigens of the erythrocyte, as indicated by agglutinability with dilutions of specific antibody, has been investigated in a group of subjects in Hiroshima. Antigen strength was found to rise to maximal levels at age 25 to 29, and decline with advancing years. Degree of irradiation from the Hiroshima atomic bomb in 1945 did not appear in the limited sample to affect this age-dependent structural property of erythrocytes. Antigen strength of females was somewhat less than that of males for those individuals from 20 to 40 years of age. When compared with group A or B subjects, individuals of group AB demonstrated full strength of both A and B antigens. Since Rh antigenicity also has been reported to change with age, it seems probable that multiple changes in the erythrocyte membrane occur with age. Further investigation into the nature of these changes may be fruitful to an understanding of aging processes at the cellular level. 13 references, 1 figure, 6 tables.

The efficacy of erythrocytes isolated from blood stored under blood bank conditions.

Science.gov (United States)

Rajashekharaiah, Vani; Koshy, Abel Abraham; Koushik, Amit Kumar; Kaur, Harsimran; Kumari, Kavita; Agrawal, Madhusudan; Priyanka; Ramya; Khatai, Smrutishree; Gowda, Vaishnavi; Kumar, Vinay

2012-12-01

The RBCs storage lesion is most carefully viewed as the sum of all the changes in RBCs occurring during the course of storage and that limit their survival. Erythrocytes were isolated from stored blood at regular intervals. Oxidative stress markers were analyzed to determine the changes during the storage. Antioxidant enzymes--(SOD and CAT), and SH showed insignificant variation whereas hemolysis, MDA and AOPP showed significant variations. The oxidative stress has not successfully overridden the protection offered by the endogenous antioxidant system. Prolonged storage may result in the onset of erythrocyte deterioration. This clearly indicates that the erythrocytes are capable of attenuating ROS with 2 weeks of storage. Copyright © 2012 Elsevier Ltd. All rights reserved.

Impact of Ficoll density gradient centrifugation on major and trace element concentrations in erythrocytes and blood plasma.

Science.gov (United States)

Lu, Ying; Ahmed, Sultan; Harari, Florencia; Vahter, Marie

2015-01-01

Ficoll density gradient centrifugation is widely used to separate cellular components of human blood. We evaluated the suitability to use erythrocytes and blood plasma obtained from Ficoll centrifugation for assessment of elemental concentrations. We determined 22 elements (from Li to U) in erythrocytes and blood plasma separated by direct or Ficoll density gradient centrifugation, using inductively coupled plasma mass spectrometry. Compared with erythrocytes and blood plasma separated by direct centrifugation, those separated by Ficoll had highly elevated iodine and Ba concentration, due to the contamination from the Ficoll-Paque medium, and about twice as high concentrations of Sr and Mo in erythrocytes. On the other hand, the concentrations of Ca in erythrocytes and plasma were markedly reduced by the Ficoll separation, to some extent also Li, Co, Cu, and U. The reduced concentrations were probably due to EDTA, a chelator present in the Ficoll medium. Arsenic concentrations seemed to be lowered by Ficoll, probably in a species-specific manner. The concentrations of Mg, P, S, K, Fe, Zn, Se, Rb, and Cs were not affected in the erythrocytes, but decreased in plasma. Concentrations of Mn, Cd, and Pb were not affected in erythrocytes, but in plasma affected by EDTA and/or pre-analytical contamination. Ficoll separation changed the concentrations of Li, Ca, Co, Cu, As, Mo, I, Ba, and U in erythrocytes and blood plasma, Sr in erythrocytes, and Mg, P, S, K, Fe, Zn, Se, Rb and Cs in blood plasma, to an extent that will invalidate evaluation of deficiencies or excess intakes. Copyright © 2014 Elsevier GmbH. All rights reserved.

Morphological Effects and Antioxidant Capacity of Solanum crispum (Natre) In Vitro Assayed on Human Erythrocytes.

Science.gov (United States)

Suwalsky, Mario; Ramírez, Patricia; Avello, Marcia; Villena, Fernando; Gallardo, María José; Barriga, Andrés; Manrique-Moreno, Marcela

2016-06-01

In order to gain insight into the molecular mechanism of the antioxidant properties of Solanum crispum, aqueous extracts of its leaves were assayed on human erythrocytes and molecular models of its membrane. Phenolics and alkaloids were detected by HPLC-MS. Scanning electron and defocusing microscopy showed that S. crispum changed erythrocytes from the normal shape to echinocytes. These results imply that molecules present in the aqueous extracts were located in the outer monolayer of the erythrocyte membrane. Dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE) were chosen as representative of phospholipid classes located in the outer and inner monolayers of the erythrocyte membrane, respectively. X-ray diffraction showed that S. crispum preferentially interacted with DMPC bilayers. Experiments regarding its antioxidant properties showed that S. crispum neutralized the oxidative capacity of HClO on DMPE bilayers; defocusing microscopy and hemolysis assays demonstrated the protective effect of S. crispum against the oxidant effects of HClO on human erythrocytes.

Quinones: reactions with hemoglobin, effects within erythrocytes and potential for antimalarial development

International Nuclear Information System (INIS)

Denny, B.J.

1986-01-01

The focus of this research was to characterize the interactions of some simple quinone like compounds with purified hemoglobin and to study the effects of these compounds within erythrocytes. It is proposed that these sorts of agents can have an antimalarial effect. The simplest compounds chosen for study were benzoquinone, methylquinone (toluquinone) and hydroquinone. When 14 C-quinone was reacted with purified hemoglobin (Hb) there was rapid binding of the first two moles of substrate per Hb molecule. An unusual property of the modified Hb's is that in the presence of a redox sensitive agent such as cytochrome c they are capable of generating superoxide anions. Within erythrocytes, quinone and toluquinone which differ only by a single methyl group have completely different effects. Toluquinone causes the cells to hemolyse and the effect was enhanced when the erythrocyte superoxide dismutase was inhibited; the effect was diminished when scavengers of activated oxygen such as histidine, mannitol and vital E were present. Benzoquinone on the other hand did not cause the cells to hemolyse and instead appeared to protect the cells from certain hemolytic stresses. Growth of malaria parasites in erythrocytes has been shown to be inhibited by activated forms of oxygen, also some quinone like agents in the past have been shown to inhibit the parasite's metabolism. An initial experiment with erythrocytes infected with malaria parasites showed that quinone and toluquinone could both inhibit the growth rate of parasites

Effect of shear stress and free radicals induced by ultrasound on erythrocytes

International Nuclear Information System (INIS)

Kondo, T.; Fukushima, Y.; Kon, H.; Riesz, P.

1989-01-01

The present study was undertaken to elucidate the mechanism of hemolysis induced by ultrasound. Ar or N2O gas was used to distinguish between cavitation with or without free radical formation (hydroxyl radicals and hydrogen atoms). Free radical formation was examined by the method of spin trapping combined with ESR. After sonication of erythrocyte suspensions, several structural and functional parameters of the erythrocyte membrane--hemolysis, membrane fluidity, membrane permeability, and membrane deformability--were examined. Although free radical formation was observed in the erythrocyte suspensions sonicated in the presence of Ar, no free radical formation was observed in the presence of N2O. However, the hemolysis behavior induced by ultrasound was similar in the presence of Ar or N2O. The membrane fluidity, permeability, and deformability of the remaining unlysed erythrocytes after sonication in the presence of Ar or N2O were unchanged and identical to those of the control cells. On the other hand, after gamma irradiation (700 Gy), the hemolysis behavior was quite different from that after sonication, and the membrane properties were significantly changed. These results suggest that hemolysis induced by sonication was due to mechanical shearing stress arising from cavitation, and that the membrane integrity of the remaining erythrocytes after sonication was the same as that of control cells without sonication. The triatomic gas, N2O, may be useful for ultrasonically disrupting cells without accompanying free radical formation

Benzophenone guttiferone A from Garcinia achachairu Rusby (Clusiaceae presents genotoxic effects in different cells of mice.

Directory of Open Access Journals (Sweden)

Peterson Menezes Terrazas

Full Text Available Benzophenones from natural sources and those of synthetic analogues present several reports of potent biological properties, and Guttiferone A represents a promising medicinal natural compound with analgesic and gastroprotective profiles. Considering that there are no reports that assess the genetic toxicity of Guttiferone A, the present study was undertaken to investigate the genotoxic potential of this benzophenone isolated from seeds of Garcinia achachairu in terms of DNA damage in different cells of Swiss albino mice using the comet assay, and its clastogenic/aneugenic effects in bone marrow cells in vivo by the micronucleus test. Cytotoxicity was assessed by scoring polychromatic (PCE and normochromatic (NCE erythrocytes ratio. Guttiferone A was administered by oral gavage at doses of 15, 30 and 60 mg/kg. The results showed that Guttiferone A produced genotoxic effects in leukocytes, liver, bone marrow, brain and testicle cells and clastogenic/aneugenic effects in bone marrow erythrocytes of mice. The PCE/NCE ratio indicated no cytotoxicity. Since guttiferone A is harmful to the genetic material we suggest caution in its use by humans.

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 diffe...... and play a major role in limiting parasite multiplication in the blood.......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...... different PfEMP1 variants, each PfEMP1 comprises several domains in its extracellular region, and the PfEMP1 repertoire in different parasites contains domain types that are serologically cross-reactive. In this longitudinal study, we followed 672 children living in an area of high malaria transmission...

Method for in vitro labelling of erythrocytes with 99mTc-pertechnetate

International Nuclear Information System (INIS)

Kostadinova, I.D.; Hadzhikostova, H.K.; Shejretova, E.T.; Garcheva-Tsacheva, M.B.

1987-01-01

The method is easy to apply and gives a possibility to lead the radiopharmaceutical directly to erythrocytes. It includes: blocking of the structures accumulating 99m Tc-pertechnetate by potassium perchlorite; attenuation of the erythrocytes by an intervenous injection of tin pyrophosphate; preparation of the necessary blood quantity with acidum citricum dextrose mixing with 99m Tc-pertechnetate and reinjection. 1 cl

The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase.

Science.gov (United States)

Haggarty, N W; Dunbar, B; Fothergill, L A

1983-01-01

The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase, comprising 239 residues, was determined. The sequence was deduced from the four cyanogen bromide fragments, and from the peptides derived from these fragments after digestion with a number of proteolytic enzymes. Comparison of this sequence with that of the yeast glycolytic enzyme, phosphoglycerate mutase, shows that these enzymes are 47% identical. Most, but not all, of the residues implicated as being important for the activity of the glycolytic mutase are conserved in the erythrocyte diphosphoglycerate mutase. PMID:6313356

Studies on the detection of erythrocytic antibodies with a radioimmuno-antiglobulin assay

International Nuclear Information System (INIS)

Djibey, I.M.

1979-01-01

The RIA with I-125-anti-IgG and I-125-anti-C3b was used. Various factors in RIA were tested for the purpose of optimisation. As a rule, incomplete anti-D (test serum of one charge) was used. Anti-Kell was used for specific problems. After optimisation of the method, patient sera were studied which contained auto- or allo-antibodies in the fresh state. More significant findings were obtained with the direct RIAGT. Indirect methods did not show a clearly enhanced detection sensitivity of erythrocyte autoantibodies, but they may serve for a closer investigation of diffuse reactions of patient sera in the enzyme test. The direct RIA is clearly of advantage in cases in which the complement Coombs test alone is positive. (orig./MG) [de

Behavior of lead and zinc in plasma, erythrocytes, and urine and ALAD in erythrocytes following intravenous infusion of CaEDTA in lead workers.

Science.gov (United States)

Araki, S; Aono, H; Fukahori, M; Tabuki, K

1984-01-01

To evaluate the effect of calcium disodium ethylenediamine tetraacetate (CaEDTA) on concentrations of lead and zinc in plasma, erythrocytes, whole blood, and urine, we administered CaEDTA by intravenous infusion for 1 hr to seven lead workers with blood lead concentrations of 46-67 micrograms/100 g (mean 54 micrograms/100 g). The plasma lead concentration (PPb) and the mobilization yield of lead in urine by CaEDTA were highest during the period between 1 and 2 hr after the infusion was started. In contrast, the lead concentration in erythrocytes (EPb) and in whole blood (BPb) remained unchanged during the 24 hr following infusion. Plasma zinc concentration (PZn) also fell rapidly following CaEDTA infusion; the decline was followed by a gradual rise in the zinc concentration in erythrocytes (EZn) without alteration in the zinc in whole blood. The mobilization yield of zinc in urine by CaEDTA (MZn) reached its highest level within 1 hr after the start of the infusion. Delta-aminolevulinic acid dehydratase (ALAD) activity in erythrocytes gradually increased for 5 hr following CaEDTA infusion. These observations suggest that (1) PPb concentration is a more sensitive indicator of the body burden of chelatable lead than is either BPb or EPb; (2) MZn is mobilized mostly from plasma during the first several hours following the start of CaEDTA infusion, and the fall in PZn concentration following infusion is compensated first by a rise in EZn concentration and then by an immediate redistribution of zinc in other organs to the blood; and (3) Pb-inhibited ALAD activity is reactivated by the increased EZn during and shortly after CaEDTA infusion.

Functional State of Rat’s Erythrocytes Under Different Stress Conditions

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A.A. Martusevich

2016-08-01

Full Text Available Background: In our early publications was shown that electrophorhetic motility of erythrocytes (EPME is a high effective criteria of adaptation response. This correlation is based on parallel development of adaptation syndrome and activation of the main organism regulatory systems, such as sympatoadrenalic and hypotalamo-hypophosial-adrenal ones. Objective: study of the influence of physical exercises and adrenaline injections on electrophorhetic motility, membrahes phospholipids spectrum and oxidative metabolism of the rats’ erythrocytes. Methods: Rats were divided into three equal groups. First group of animals was control (n=10; without any manipulations. Rats of second group were subjected to physical load in the form of a sailing duration of 15 minutes with a cargo amounting to 10% of animal body weight (water temperature – 26-280C. Rats of third group were intraperitoneally injected with adrenaline hydrochloride (0.1 mg/kg. Blood sampling was made from the sublingual vein in 15, 30, 60, 120 minutes and 24 hours after exposure. We estimated the dynamics of the electrophorhetic motility of erythrocytes (EPME, the phospholipid spectrum of erythrocytes membranes, the concentration of malonic dialdehyde (MDA and the state of the glutathione system. Results and conclusions: The study suggests that red blood cell as a biological system is capable for realization of stress response may develop a special “alarm reaction” after action of the stress agent. This response initiates activation of free radical processes and phospholipids profile in erythrocyte membranes with reducing of its electronegativity. This stage enhances the activity of the antioxidant system, is limiting the development of lipid peroxidation processes, and leads to the development of "adaptation stage" of the cellular system, coupled with the restoration of the electronegativity of the membrane and the mobilization of reserves of low molecular antioxidants, particularly

[Cholinesterases in total blood measured with a semiquantitative technique, and plasma or erythrocyte cholinesterases measured with quantitative techniques].

Science.gov (United States)

Carmona-Fonseca, Jaime

2007-06-01

An equivalence model which allows comparison of blood cholinesterase values, measured by Lovibond (semiquantitative technique), and Michel, EQM, Monotest (erythrocyte and plasma cholinesterases) values measured by quantitative techniques is required. The performance of Lovibond (Edson tintometric and Limperos & Ranta techniques) were compared with quantitative techniques. The experimental design was descriptive, cross-sectional, and prospective. From a working population (18-59 years) in Valle de Aburrá and Near East of Antioquia. 827 representative samples were chosen for their lack of exposure to cholinesterase-inhibiting plaguicides and affiliated to the Social Security System. (1) 827 workers were classified by Lovibond in four categories: 821 values with 75% of cholinesterase activity or greater (categories 75, 87.5 and 100%) and 6 with cholinesterase activity smaller than 75%. (2) With each quantitative method, the mean values of erythrocyte and plasmatic cholinesterase corresponding to the four values obtained with Lovibond were statistically different to each other. (3) The mean values of each quantitative technique increased when increased the tintometric method value. (4) Lovibond classified the low enzymatic erythrocyte activity very poorly (61-73%), but the classification of the low enzymatic plasma activity was almost completely in error (94-96%). The values of erythrocyte or plasma cholinesterase were adequately estimated by both the quantitative techniques of Michel and EQM and by Lovibond, but only when the enzymatic activity is normal. Lovibond, however, had a poor capacity to designate as "low" the values that were low according to the quantitative tests.

Erythrocyte remodeling in Plasmodium berghei infection: the contribution of SEP family members.

Science.gov (United States)

Currà, Chiara; Pace, Tomasino; Franke-Fayard, Blandine M D; Picci, Leonardo; Bertuccini, Lucia; Ponzi, Marta

2012-03-01

The malaria parasite Plasmodium largely modifies the infected erythrocyte through the export of proteins to multiple sites within the host cell. This remodeling is crucial for pathology and translocation of virulence factors to the erythrocyte surface. In this study, we investigated localization and export of small exported proteins/early transcribed membrane proteins (SEP/ETRAMPs), conserved within Plasmodium genus. This protein family is characterized by a predicted signal peptide, a short lysine-rich stretch, an internal transmembrane domain and a highly charged C-terminal region of variable length. We show here that members of the rodent Plasmodium berghei family are components of the parasitophorous vacuole membrane (PVM), which surrounds the parasite throughout the erythrocytic cycle. During P. berghei development, vesicle-like structures containing these proteins detach from the PVM en route to the host cytosol. These SEP-containing vesicles remain associated with the infected erythrocyte ghosts most probably anchored to the membrane skeleton. Transgenic lines expressing the green fluorescent protein appended to different portions of sep-coding region allowed us to define motifs required for protein export. The highly charged terminal region appears to be involved in protein-protein interactions. © 2011 John Wiley & Sons A/S.

Erythrocytes L-arginine y+ transporter inhibition by N-ethylmaleimide in ice-bath.

Science.gov (United States)

Pinheiro da Costa, Bartira Ercília; de Almeida, Priscilla Barcellos; Conceição, Ioná Rosine; Antonello, Ivan Carlos Ferreira; d'Avila, Domingos O; Poli-de-Figueiredo, Carlos Eduardo

2010-11-01

Erythrocytes L: -arginine uptake is conveyed by y+ and y+L membrane transport systems. Pre-incubation with N-ethylmaleimide for 10 min at 37°C inhibits the y+ system. The aim of this study was to determine the ideal pre-incubation temperature in evaluating y+ and y+L systems. Cells were pre-incubated with or without N-ethylmaleimide for 10 min at 4°C and 37°C. L: -Arginine uptake was quantified by radioisotope and standard erythrocytes membrane flux methodology. Results demonstrate that erythrocytes L: -arginine content is depleted by pre-incubation at 37°C for 10 min, thus changing the V (max) measurement. The inhibitory effect of N-ethylmaleimide pre-incubation was temperature independent and already complete after 1 min of incubation. No significant difference in kinetic parameters was detected between cells pre-incubated at 37°C or 4°C, under zero-trans conditions. In conclusion, we suggest that measurement of erythrocytes L: -arginine uptake by y+ and y+L systems could be carried out without N-ethylmaleimide pre-incubation at 37°C.

Effects of centrifugation on transmembrane water loss from normal and pathologic erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Kaperonis, A.A.; Chien, S.

1989-02-01

Plasma /sup 125/I-albumin was used as a marker of extracellular dilution in order to study the effect of high-speed centrifugation on transmembrane water distribution in several types of human red cells, including normal (AA), hemoglobin variants (beta A, AS, SC, beta S, and SS), and those from patients with hereditary spherocytosis. SS and AA erythrocytes were also examined for changes in intracellular hemoglobin concentration of three different density fractions and with increasing duration of spin. The minimum force and duration of centrifugation required to impair water permeability were found to vary with the red cell type, the anticoagulant used (heparin or EDTA), the initial hematocrit of the sample centrifuged, as well as among the individual erythrocyte fractions within the same sample. When subjecting pathologic erythrocytes to high-speed centrifugation, the /sup 125/I-albumin dilution technique can be used to determine whether the centrifugation procedure has led to an artifactual red cell water loss and to correct for this when it does occur. An abnormal membrane susceptibility to mechanical stress was demonstrated in erythrocytes from patients with hereditary spherocytosis and several hemoglobinopathies.

Curcumin Protects -SH Groups and Sulphate Transport after Oxidative Damage in Human Erythrocytes

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Rossana Morabito

2015-05-01

Full Text Available Background/Aims: Erythrocytes, continuously exposed to oxygen pressure and toxic compounds, are sensitive to oxidative stress, namely acting on integral Band 3 protein, with consequences on cell membranes deformability and anion transport efficiency. The aim of the present investigation, conducted on human erythrocytes, is to verify whether curcumin (1 or 10µM, a natural compound with proved antioxidant properties, may counteract Band 3-mediated anion transport alterations due to oxidative stress. Methods: Oxidative conditions were induced by exposure to, alternatively, either 2 mM N-ethylmaleimide (NEM or pH-modified solutions (6.5 and 8.5. Rate constant for SO4= uptake and -SH groups estimation were measured to verify the effect of oxidative stress on anion transport efficiency and erythrocyte membranes. Results: After the exposure of erythrocytes to, alternatively, NEM or pH-modified solutions, a significant decrease in both rate constant for SO4= uptake and -SH groups was observed, which was prevented by curcumin, with a dose-dependent effect. Conclusions: Our results show that: i the decreased efficiency of anion transport may be due to changes in Band 3 protein structure caused by cysteine -SH groups oxidation, especially after exposure to NEM and pH 6.5; ii 10 µM Curcumin is effective in protecting erythrocytes from oxidative stress events at level of cell membrane transport.

Micronucleus frequency in Danish schoolchildren and their mothers from the DEMOCOPHES population

DEFF Research Database (Denmark)

Mørck, Thit A.; Vande Loock, Kim; Poulsen, Maria Bech

2016-01-01

organic pollutants and dioxin-like activity measured in the sameparticipants. The MN frequency analysis was performed with the cytokinesis-block micronucleus(CBMN) assay and included 100 children and 119 mothers. We found a significant correlationbetween mothers and children in the levels of micronuclei...... in 1000 binucleated T lymphocytes(‰MNBN) and in the proliferation index. Further the levels of ‰MNBN were significantly higherin mothers compared with their children. No significant associations were found for ‰MNBNfor traffic related exposure in neither children nor their mothers. In children, a 2.......5 times highermicronuclei in mononuclear T lymphocytes were found in children living within 50 m of a busyroad, however, this was not found in mothers or in MNBN and the effect of exposure to road trafficon MN frequency needs further investigation. No significant associations were found between...

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 ...

Oxidative Damage in Erythrocytes During Cold Storage With Organ Preservation Solution

OpenAIRE

MEMMEDOĞLU, Akif B.

1999-01-01

It is known that erythrocyte aggregation in renal tissue during preserva-tion is cause of microcirculation defects in the reperfusion period. The aim of our study is to investigate oxidative damage in erythrocytes relative to the time of cold ischemia during organ preservation and relationship between lipid peroxidation and development of these damages. In experiments with a rabbit model, explanted kidneys were exposed to perfusion and 96 hours preservation with Euro-Collins (EC) in the 1...

Effects of Radiographic Contrast Media on the Micromorphology of the Junctional Complex of Erythrocytes Visualized by Immunocytology

Science.gov (United States)

Franke, Ralf-Peter; Krüger, Anne; Scharnweber, Tim; Wenzel, Folker; Jung, Friedrich

2014-01-01

Effects of radiographic contrast media (RCM) application were demonstrated in vitro and in vivo where the injection of RCM into the A. axillaris of patients with coronary artery disease was followed by a significant and RCM-dependent decrease of erythrocyte velocity in downstream skin capillaries. Another study in pigs revealed that the deceleration of erythrocytes coincided with a significant reduction of the oxygen partial pressure in the myocardium—supplied by the left coronary artery—after the administration of RCM into this artery. Further reports showed RCM dependent alterations of erythrocytes like echinocyte formation and exocytosis, sequestration of actin or band 3 and the buckling of endothelial cells coinciding with a formation of interendothelial fenestrations leading to areas devoid of endothelial cells. Key to morphological alterations of erythrocytes is the membrane cytoskeleton, which is linked to the band 3 in the erythrocyte membrane via the junctional complex. Fundamental observations regarding the cell biological and biochemical aspects of the structure and function of the cell membrane and the membrane cytoskeleton of erythrocytes have been reported. This review focuses on recent results gained, e.g., by advanced confocal laser scanning microscopy of different double-stained structural elements of the erythrocyte membrane cytoskeleton. PMID:25222553

Nuclear magnetic resonance investigation of erythrocyte membranes in chronic myeloproliferative disorders.

Science.gov (United States)

Morariu, V V; Petrov, L

1986-07-01

The temperature dependence of the apparent water diffusional exchange through erythrocyte membranes in cases of policitemia vera, chronic granulocytic leukemia and primary myelofibrosis was measured by using a nuclear magnetic resonance method in the presence of Mn2+. The thermal transition shifted to lower temperatures in all cases, regardless of the stage of the disease, suggesting a structural alteration of the membrane. The shift of transition indirectly suggests a lower penetration of the erythrocytes by Mn2+. The water exchange time at 37 degrees C also increased, mainly in the blast crisis; it seems to have a prognostic value of some clinical interest. No simple correlation of the water exchange and the following clinical investigations was observed: the white count, the percentage of promyelocites and myeloblasts, the sedimentation rate of blood, the osmotic fragility of erythrocytes, the total concentration of proteins, albumin and immunoglobulins, respectively, in plasma.

The influence of split doses of γ-radiation on human erythrocytes

International Nuclear Information System (INIS)

Koziczak, R.; Gonciarz, M.; Krokosz, A.; Szweda-Lewandowska, Z.

2003-01-01

Human erythrocyte suspensions in an isotonic Na-phosphate buffer, pH 7.4, of hematocrit of 2% were exposed under air to gamma radiation at a dose rate of 2.2 kGy. Erythrocytes were irradiated with single doses, and identical doses split into two fractions with an interval time of 3.5 h between following exposures. The obtained results indicated that the irradiation of enucleated human erythrocytes with split doses caused a reduction of hemolysis (2.4 times), a decrease in the level of damage to membrane lipids and the contents of MetHb, compared with identical single doses. However, the splitting of radiation doses did not change the level of damage to the membrane proteins, as was estimated with a maleimide spin label. The obtained results suggest that a decrease in the level of damage to lipids was related to a decrease in hemolysis. (author)

[Effects of HiLo for two weeks on erythrocyte immune adhesion and leukocyte count of swimmers].

Science.gov (United States)

Zhao, Yong-Cai; Gao, Bing-Hong; Wu, Ge-Lin; Zhang, Jiu-Li

2012-07-01

To investigate the effects of living high-training low (HiLo) on innate immunity in blood of elite swimmers. Six female swimmers undertook HiLo for two weeks, erythrocyte adhesion function and counts of leukocyte were tested in different time of training period. Red blood cell C3b receptor ring rate (RBC-C3bRR) decreased and red blood cell immune complex matter ring rate (RBC-ICR) increased significantly (P < 0.05), the two markers returned to base line 1 week after training. Counts of leukocyte and granulocyte decreased significantly (P < 0.05), and they recovered 1 week after training; Counts of lymphocyte and monocyte decreased without significance during training and did not recovered after training. Immunity of erythrocyte and granulocyte decreased quickly, but lymphocyte and monocyte recovered slowly, swimmers were adaptive to the training.

Erythrocyte creatine as a marker of intravascular hemolysis due to left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

Science.gov (United States)

Kubo, Toru; Okumiya, Toshika; Baba, Yuichi; Hirota, Takayoshi; Tanioka, Katsutoshi; Yamasaki, Naohito; Sugiura, Tetsuro; Doi, Yoshinori L; Kitaoka, Hiroaki

2016-03-01

Erythrocyte creatine, a marker of erythrocyte age that increases with shortening of erythrocyte survival, has been reported to be a quantitative and reliable marker for intravascular hemolysis. We hypothesized that hemolysis could also occur due to intraventricular obstruction in patients with hypertrophic cardiomyopathy (HCM). The purpose of this study was to examine the presence of subclinical hemolysis and the relation between intravascular hemolysis and intraventricular pressure gradient (IVPG). We measured erythrocyte creatine in 92 HCM patients. Twelve patients had left ventricular outflow tract obstruction (LVOTO), 4 had midventricular obstruction (MVO), and the remaining 76 were non-obstructive. Erythrocyte creatine levels ranged from 0.92 to 4.36μmol/g hemoglobin. Higher levels of erythrocyte creatine were associated with higher IVPG (r=0.437, pcreatine levels are high (≥1.8μmol/g hemoglobin), subclinical hemolysis is considered to be present. Half of LVOTO patients and no MVO patients showed high erythrocyte creatine levels. Although non-obstructive patients did not show significant intraventricular obstruction at rest, some showed high erythrocyte creatine levels. When LVOT-PG was measured during the strain phase of the Valsalva maneuver in 20 non-obstructive patients, 7 of those 20 patients showed LVOTO. In the 20 patients, there was no relation between erythrocyte creatine levels and LVOT-PG before the Valsalva maneuver (r=0.125, p=0.600), whereas there was a significant correlation between erythrocyte creatine and LVOT-PG provoked by the Valsalva maneuver (r=0.695, p=0.001). There is biochemical evidence of subclinical hemolysis in patients with HCM, and this hemolysis seems to be associated with LVOTO provoked by daily physical activities. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

The Effect of Covalently-Attached ATRP-Synthesized Polymers on Membrane Stability and Cytoprotection in Human Erythrocytes.

Science.gov (United States)

Clafshenkel, William P; Murata, Hironobu; Andersen, Jill; Creeger, Yehuda; Koepsel, Richard R; Russell, Alan J

2016-01-01

Erythrocytes have been described as advantageous drug delivery vehicles. In order to ensure an adequate circulation half-life, erythrocytes may benefit from protective enhancements that maintain membrane integrity and neutralize oxidative damage of membrane proteins that otherwise facilitate their premature clearance from circulation. Surface modification of erythrocytes using rationally designed polymers, synthesized via atom-transfer radical polymerization (ATRP), may further expand the field of membrane-engineered red blood cells. This study describes the fate of ATRP-synthesized polymers that were covalently attached to human erythrocytes as well as the effect of membrane engineering on cell stability under physiological and oxidative conditions in vitro. The biocompatible, membrane-reactive polymers were homogenously retained on the periphery of modified erythrocytes for at least 24 hours. Membrane engineering stabilized the erythrocyte membrane and effectively neutralized oxidative species, even in the absence of free-radical scavenger-containing polymers. The targeted functionalization of Band 3 protein by NHS-pDMAA-Cy3 polymers stabilized its monomeric form preventing aggregation in the presence of the crosslinking reagent, bis(sulfosuccinimidyl)suberate (BS3). A free radical scavenging polymer, NHS-pDMAA-TEMPO˙, provided additional protection of surface modified erythrocytes in an in vitro model of oxidative stress. Preserving or augmenting cytoprotective mechanisms that extend circulation half-life is an important consideration for the use of red blood cells for drug delivery in various pathologies, as they are likely to encounter areas of imbalanced oxidative stress as they circuit the vascular system.

The Effect of Covalently-Attached ATRP-Synthesized Polymers on Membrane Stability and Cytoprotection in Human Erythrocytes.

Directory of Open Access Journals (Sweden)

William P Clafshenkel

Full Text Available Erythrocytes have been described as advantageous drug delivery vehicles. In order to ensure an adequate circulation half-life, erythrocytes may benefit from protective enhancements that maintain membrane integrity and neutralize oxidative damage of membrane proteins that otherwise facilitate their premature clearance from circulation. Surface modification of erythrocytes using rationally designed polymers, synthesized via atom-transfer radical polymerization (ATRP, may further expand the field of membrane-engineered red blood cells. This study describes the fate of ATRP-synthesized polymers that were covalently attached to human erythrocytes as well as the effect of membrane engineering on cell stability under physiological and oxidative conditions in vitro. The biocompatible, membrane-reactive polymers were homogenously retained on the periphery of modified erythrocytes for at least 24 hours. Membrane engineering stabilized the erythrocyte membrane and effectively neutralized oxidative species, even in the absence of free-radical scavenger-containing polymers. The targeted functionalization of Band 3 protein by NHS-pDMAA-Cy3 polymers stabilized its monomeric form preventing aggregation in the presence of the crosslinking reagent, bis(sulfosuccinimidylsuberate (BS3. A free radical scavenging polymer, NHS-pDMAA-TEMPO˙, provided additional protection of surface modified erythrocytes in an in vitro model of oxidative stress. Preserving or augmenting cytoprotective mechanisms that extend circulation half-life is an important consideration for the use of red blood cells for drug delivery in various pathologies, as they are likely to encounter areas of imbalanced oxidative stress as they circuit the vascular system.

Membrane-Wrapping Contributions to Malaria Parasite Invasion of the Human Erythrocyte

Science.gov (United States)

Dasgupta, Sabyasachi; Auth, Thorsten; Gov, Nir S.; Satchwell, Timothy J.; Hanssen, Eric; Zuccala, Elizabeth S.; Riglar, David T.; Toye, Ashley M.; Betz, Timo; Baum, Jake; Gompper, Gerhard

2014-01-01

The blood stage malaria parasite, the merozoite, has a small window of opportunity during which it must successfully target and invade a human erythrocyte. The process of invasion is nonetheless remarkably rapid. To date, mechanistic models of invasion have focused predominantly on the parasite actomyosin motor contribution to the energetics of entry. Here, we have conducted a numerical analysis using dimensions for an archetypal merozoite to predict the respective contributions of the host-parasite interactions to invasion, in particular the role of membrane wrapping. Our theoretical modeling demonstrates that erythrocyte membrane wrapping alone, as a function of merozoite adhesive and shape properties, is sufficient to entirely account for the first key step of the invasion process, that of merozoite reorientation to its apex and tight adhesive linkage between the two cells. Next, parasite-induced reorganization of the erythrocyte cytoskeleton and release of parasite-derived membrane can also account for a considerable energetic portion of actual invasion itself, through membrane wrapping. Thus, contrary to the prevailing dogma, wrapping by the erythrocyte combined with parasite-derived membrane release can markedly reduce the expected contributions of the merozoite actomyosin motor to invasion. We therefore propose that invasion is a balance between parasite and host cell contributions, evolved toward maximal efficient use of biophysical forces between the two cells. PMID:24988340

EFFECT OF PESTICIDES ON RAT (Rattus norvegicus ERYTHROCYTES ANTIOXIDANT ENZYMES IN VITRO

Directory of Open Access Journals (Sweden)

Jasna Friščić

2014-10-01

Full Text Available Abstract: In the last century, maximum in herbicide production was achieved. Growing use of herbicides initiated the need for continuous evaluation of damaging effects of herbicides on human health and environment. Paraquat is the trade name for N,N′-dimethyl-4,4′-bipyridinium dichloride and one of the most widely used herbicides in the world. Although mechanism of paraquat toxicity remains undefined, a great portion of toxicity is attributed to the process of redox cycling. In this research, rat erythrocytes were exposed to various paraquat concentrations (0, 0.25, 0.5, 0.75, 1.25 mM. Changes in antioxidant enzymes activity, catalase and superoxide dismutase were determined, and also the activity of erythrocyte acetylcholinesterase. Obtained results show damaging effects of paraquat on erythrocytes due to oxidative stress.

Dynamics of interaction between complement-fixing antibody/dsDNA immune complexes and erythrocytes. In vitro studies and potential general applications to clinical immune complex testing

International Nuclear Information System (INIS)

Taylor, R.P.; Horgan, C.; Hooper, M.; Burge, J.

1985-01-01

Soluble antibody/ 3 H-double-stranded PM2 DNA (dsDNA) immune complexes were briefly opsonized with complement and then allowed to bind to human erythrocytes (via complement receptors). The cells were washed and subsequently a volume of autologous blood in a variety of media was added, and the release of the bound immune complexes from the erythrocytes was studied as a function of temperature and time. After 1-2 h, the majority of the bound immune complexes were not released into the serum during blood clotting at either 37 degrees C or room temperature, but there was a considerably greater release of the immune complexes into the plasma of blood that was anticoagulated with EDTA. Similar results were obtained using various conditions of opsonization and also using complexes that contained lower molecular weight dsDNA. Thus, the kinetics of release of these antibody/dsDNA immune complexes differed substantially from the kinetics of release of antibody/bovine serum albumin complexes that was reported by others. Studies using the solution phase C1q immune complex binding assay confirmed that in approximately half of the SLE samples that were positive for immune complexes, there was a significantly higher level of detectable immune complexes in plasma vs. serum. Freshly drawn erythrocytes from some SLE patients exhibiting this plasma/serum discrepancy had IgG antigen on their surface that was released by incubation in EDTA plasma. Thus, the higher levels of immune complexes observed in EDTA plasma vs. serum using the C1q assay may often reflect the existence of immune complexes circulating in vivo bound to erythrocytes

Fundamental studies on the insulin receptor in rabbit erythrocytes

Energy Technology Data Exchange (ETDEWEB)

Shinomiya, Y; Kagawa, S; Konishi, Y; Morimoto, H; Tsumura, Y [Hyogo Medical Coll. (Japan)

1975-09-01

The authors studied the binding of insulin to rabbit erythrocytes as a mode case in the hope of characterizing the physiologic role of the binding of insulin to receptor in both normal adults and patients. Specific binding sites for insulin were detected in rabbit erythrocytes. The characteristics of the binding were similar to those observed in other target tissues. The specific binding of /sup 125/I-labeled insulin was competitively inhibited by a small amount of unlabeled insulin and was completely inhibited by 1,000 ng/ml of unlabeled insulin. Glucagon, however, had no effect on the insulin binding to fat cells or liver membranes nor had it any effect on the binding of insulin to rabbit erythrocytes. Scatchard analysis of this binding reaction indicated two different binding sites with Ksub(aff)=3.2 x 10/sup 8//M, Ksub(diss)=3.1 x 10/sup -9/M; Ksub(aff)=1.4 x 10/sup 8//M, Ksub(diss)=7.1 x 10/sup -9/M respectively, and the binding capacities of each site were estimated at 0.011 ng/4 x 10/sup 8/ cells and 0.138 ng/4 x 10/sup 8/ cells. The binding of /sup 125/I-insulin to rabbit erythrocytes was a saturable function of the insulin concentration and was a linear function of cell concentration. The pH optimum for the reaction was 7.4 at 0/sup 0/C, the amount of insulin binding increased continuously under the reaction and this binding reaction reached a steady state after 10 to 15hr. On the other hand, the specific binding of insulin at higher temperatures showed maximal amounts after 20 to 30 min. and subsequently fell off at later time points.

The Duffy binding protein (PkDBPαII) of Plasmodium knowlesi from Peninsular Malaysia and Malaysian Borneo show different binding activity level to human erythrocytes.

Science.gov (United States)

Lim, Khai Lone; Amir, Amirah; Lau, Yee Ling; Fong, Mun Yik

2017-08-11

The zoonotic Plasmodium knowlesi is a major cause of human malaria in Malaysia. This parasite uses the Duffy binding protein (PkDBPαII) to interact with the Duffy antigen receptor for chemokines (DARC) receptor on human and macaque erythrocytes to initiate invasion. Previous studies on P. knowlesi have reported distinct Peninsular Malaysia and Malaysian Borneo PkDBPαII haplotypes. In the present study, the differential binding activity of these haplotypes with human and macaque (Macaca fascicularis) erythrocytes was investigated. The PkDBPαII of Peninsular Malaysia and Malaysian Borneo were expressed on the surface of COS-7 cells and tested with human and monkey erythrocytes, with and without anti-Fy6 (anti-Duffy) monoclonal antibody treatment. Binding activity level was determined by counting the number of rosettes formed between the transfected COS-7 cells and the erythrocytes. Anti-Fy6 treatment was shown to completely block the binding of human erythrocytes with the transfected COS-7 cells, thus verifying the specific binding of human DARC with PkDBPαII. Interestingly, the PkDBPαII of Peninsular Malaysia displayed a higher binding activity with human erythrocytes when compared with the Malaysian Borneo PkDBPαII haplotype (mean number of rosettes formed = 156.89 ± 6.62 and 46.00 ± 3.57, respectively; P < 0.0001). However, no difference in binding activity level was seen in the binding assay using M. fascicularis erythrocytes. This study is the first report of phenotypic difference between PkDBPαII haplotypes. The biological implication of this finding is yet to be determined. Therefore, further studies need to be carried out to determine whether this differential binding level can be associated with severity of knowlesi malaria in human.

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.

Alkaline comet assay in liver and stomach, and micronucleus assay in bone marrow, from rats treated with 2-acetylaminofluorene, azidothymidine, cisplatin, or isobutyraldehyde.

Science.gov (United States)

Kraynak, A R; Barnum, J E; Cunningham, C L; Ng, A; Ykoruk, B A; Bennet, B; Stoffregen, D; Merschman, M; Freeland, E; Galloway, S M

2015-07-01

As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM) initiative international validation study of the in vivo rat alkaline comet assay (comet assay), we examined the ability of the assay to determine the genotoxicity of 2-acetylaminofluorene (AAF), azidothymidine (AZT), cisplatin (CPN), and isobutyraldehyde (IBA) in liver and glandular stomach of male Sprague-Dawley rats. Rats were given oral doses of test compound or control once daily for three days. High dose levels were approximately maximum tolerated doses and were based on preliminary range-finding studies. Tissues were harvested 3h after the final dose (48h after the initial dose). A bone marrow micronucleus assay (MN) was also conducted on the rats treated with AZT, CPN, and IBA. Acute toxic effects of treatment were determined primarily through histomorphologic analysis of liver and stomach but also by body weight and serum liver enzyme changes. The comet assay was conducted on fresh tissue preparations but frozen samples from two studies were also assayed. Statistically significant dose-related differences in comet % DNA in tail were found in liver and stomach for the genotoxin AZT and in liver for the genotoxin CPN, but not in liver or stomach for the non-genotoxin IBA. Statistically significant differences in % DNA in tail were measured in liver for the low and mid dose of the genotoxin AAF, but not the high dose. The comet assays of frozen liver suspensions from CPN- and AAF-treated rats yielded comparable results to the assays of fresh preparations. There were no indications of significant toxicity induced by any treatment. The micronucleus assay was positive for CPN and AZT and negative for IBA. In conclusion, the in vivo comet assay is capable of detecting genotoxic effects of a variety of chemicals and may fill an important role in the genotoxicity test battery. Copyright © 2015 Elsevier B.V. All rights reserved.

Cross-sectional associations of cortical β-amyloid with erythrocyte membrane long-chain polyunsaturated fatty acids in older adults with subjective memory complaints.

Science.gov (United States)

Hooper, Claudie; De Souto Barreto, Philipe; Payoux, Pierre; Salabert, Anne Sophie; Guyonnet, Sophie; Andrieu, Sandrine; Vellas, Bruno

2017-08-01

Omega-3 (n-3) and 6 (n-6) polyunsaturated fatty acids (PUFAs) have been associated with reduced cognitive decline in observational studies. Hence, we examined the cross-sectional associations between cortical β-amyloid (Aβ) and erythrocyte membrane PUFAs in 61 non-demented elderly individuals reporting subjective memory complaints from the Multidomain Alzheimer Preventive Trial placebo arm. Cortical-to-cerebellar standard uptake value ratios were obtained using [ 18 F] florbetapir positron emission tomography. Fatty acids were measured in erythrocyte membranes by gas chromatography. Associations were explored using adjusted multiple linear regression models and were considered significant at p ≤ 0.005 after correction for multiple testing (10 comparisons). We found no significant associations between cortical Aβ and erythrocyte membrane PUFAs. The associations closest to significance after adjustment were those between Aβ and erythrocyte membrane arachidonic acid (without apolipoprotein E status adjustment: B-coefficient, 0.03; CI, 0.01, 0.05; p = 0.02. Including Apolipoprotein E adjustment: B-coefficient, 0.03; CI, 0.00, 0.06; p = 0.04) and Aβ and erythrocyte membrane linoleic acid (without apolipoprotein E status adjustment: B-coefficient, -0.02; CI, -0.04, 0.00; p = 0.02. Including Apolipoprotein E adjustment: B-coefficient, -0.02; CI, -0.04, 0.00; p = 0.09). Furthermore, the association between Aβ and erythrocyte membrane arachidonic acid seemed to be specific to Apolipoprotein E ε4 non-carriers (B-coefficient 0.03, CI: 0.00, 0.06, p = 0.03, n = 36). In contrast, no association was found between Aβ and erythrocyte membrane linoleic acid in Apolipoprotein E ε4 stratified analysis. Investigating the relationships between Aβ and PUFAs longitudinally would provide further evidence as to whether fatty acids, particularly arachidonic acid and linoleic acid, might modulate cognition through Aβ-dependent mechanisms. © 2017 International

Micronucleus Assay in Exfoliated Buccal Epithelial Cells Using Liquid Based Cytology Preparations in Building Construction Workers.

Science.gov (United States)

Arul, P; Smitha, Shetty; Masilamani, Suresh; Akshatha, C

2018-01-01

Cytogenetic damage in exfoliated buccal epithelial cells due to environmental and occupational exposure is often monitored by micronucleus (MN) assay using liquid based cytology (LBC) preparations. This study was performed to evaluate MN in exfoliated buccal epithelial cells of building construction workers using LBC preparations. LBC preparations of exfoliated buccal epithelial cells from 100 subjects [50 building construction workers (cases) and 50 administrative staffs (controls)] was evaluated by May-Grunwald Giemsa, Hematoxylin and Eosin and Papanicolaou stains. Student's t test was used for statistical analysis and a P value of 5 years) and smokers and non-smokers of cases (P=0.001). However, there were meaningful differences regarding mean frequencies of MN between smokers, non-smokers, those with alcohol consumption or not in cases and controls using various stains (P=0.001). There was an increased risk of cytogenetic damage in building construction workers. However, evaluation of MN of exfoliated buccal epithelial cells in building construction workers serve as a minimally invasive biomarker for cytogenetic damage. LBC preparations can be applied for MN assay as it improves the quality of smears and cell morphology, decreases the confounding factors and reduces false positive results.

Effects of erythrocyte infusion on VO2max at high altitude

DEFF Research Database (Denmark)

Young, Jette Feveile; Sawka, M N; Muza, S R

1996-01-01

This study investigated whether autologous erythrocyte infusion would ameliorate the decrement in maximal O2 uptake (VO2max) experienced by lowlanders when they ascend to high altitude. VO2max was measured in 16 men (treadmill running) at sea level (SL) and on the 1st (HA1) and 9th (HA9) days...... of high-altitude (4,300 m) residence. After VO2max was measured at SL, subjects were divided into two matched groups (n = 8). Twenty-four hours before ascent to high altitude, the experimental group received a 700-ml infusion of autologous erythrocytes and saline (42% hematocrit), whereas the control...... group received only saline. The VO2max of erythrocyte-infused [54 +/- 1 (SE) ml.kg-1.min-1] and control subjects (52 +/- 2 ml.kg-1.min-1) did not differ at SL before infusion. The decrement in VO2max on HA1 did not differ between groups, averaging 26% overall, despite higher (P

Antioxidant status of erythrocytes and their response to oxidative challenge in humans with argemone oil poisoning

International Nuclear Information System (INIS)

Babu, Challagundla K.; Khanna, Subhash K.; Das, Mukul

2008-01-01

Oxidative damage of biomolecules and antioxidant status in erythrocytes of humans from an outbreak of argemone oil (AO) poisoning in Kannauj (India) and AO intoxicated experimental animals was investigated. Erythrocytes of the dropsy patients and AO treated rats were found to be more susceptible to 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced peroxidative stress. Significant decrease in RBC glutathione (GSH) levels (46, 63%) with concomitant enhancement in oxidized glutathione (172, 154%) levels was noticed in patients and AO intoxicated animals. Further, depletion of glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione-S-transferase (GST) (42-52%) was observed in dropsy patients. Oxidation of erythrocyte membrane lipids and proteins was increased (120-144%) in patients and AO treated animals (112-137%) along with 8-OHdG levels in whole blood (180%) of dropsy patients. A significant reduction in α-tocopherol content (68%) was noticed in erythrocytes of dropsy patients and hepatic, plasma and RBCs of AO treated rats (59-70%) thereby indicating the diminished antioxidant potential to scavenge free radicals or the limited transport of α-tocopherol from liver to RBCs leading to enhanced oxidation of lipids and proteins in erythrocytes. These studies implicate an important role of erythrocyte degradation in production of anemia and breathlessness in epidemic dropsy

[The physiologic significance of 2,3-diphosphoglycerate and changes in its erythrocyte levels in an experiment].

Science.gov (United States)

Béder, I; Orgonásová, M; Brozman, B; Horecký, J; Mataseje, A

1990-05-01

The regulatory effect of 2,3-DPG on oxygen transport and binding to hemoglobin was analyzed. Under conditions of substitution hemodilution by isooncotic 3.4% Rheodextran (Spofa), changes in the content of 2,3-DPG in arterial and venous blood were enzymatically determined over several days. Reference values of 2,3-DPG were obtained in the studied series of dogs (2.05 +/- 0.74 x 10(-6) mol.ml-1 in whole blood 4.69 +/- 1.52 x 10(-6) mol.g-1 of erythrocyte volume, and 13.39 +/- 2.82 x 10(-6) mol.ml-1 of hemoglobin). In anesthetized animals the content of 2,3-DPG in arterial blood was significantly higher (6.28 +/- 0.84 x 10(-6) mol.ml-1 of erythrocyte volume) than in venous blood (6.01 +/- 0.80 x 10(-6) mol.ml-1 of erythrocyte volume). At substitution hemodilution the 2,3-DPG content in erythrocytes of venous blood decreased from 5.46 +/- 0.67 to 4.97 +/- 1.31 x 10(-6) mol.ml-1 of erythrocyte volume. The subsequent increase to 6.04 +/- 0.71 x 10(-6) mol.ml-1 of erythrocyte volume was achieved by nonlinear increase over the following days, at persisting low hemoglobin content in blood.

Evidence that the low-affinity folate-binding protein in erythrocyte hemolysate is identical to hemoglobin

International Nuclear Information System (INIS)

Hansen, S.I.; Holm, J.; Lyngbye, J.

1981-01-01

Gel filtration studies on erythrocyte hemolysate demonstrated the presence of a folate binding protein, apparently of the low-affinity type, that co-elutes with hemoglobin. Further, the folate binder eluted with a low salt concentration after DEAE-Sepharose CL-6B anion-exchange chromatography of erythrocyte hemolysate at pH 6.3. The chromatographic behavior of hemoglobin labeled with [3H]folate was so similar to that of the present binder as to suggest that the folate binder in erythrocytes is in fact hemoglobin

HUMN project initiative and review of validation, quality control and prospects for further development of automated micronucleus assays using image cytometry systems

Czech Academy of Sciences Publication Activity Database

Fenech, M.; Kirsch-Volders, M.; Rössnerová, Andrea; Šrám, Radim; Romm, H.; Bolognesi, C.; Ramakumar, A.; Soussaline, F.; Schunck, CH.; Elhajouji, A.; Anwar, W.; Bonassi, S.

2013-01-01

Roč. 216, č. 5 (2013), s. 541-552 ISSN 1438-4639 R&D Projects: GA ČR GAP503/11/0084 Grant - others:Project NewGenesis(XE) FOOD -CT-2005-016320 Institutional support: RVO:68378041 Keywords : Micronucleus * Cytokinesis-block * Automation Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 3.276, year: 2013

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

Energy Technology Data Exchange (ETDEWEB)

Jin, Hua; Xing, Xiaobo [Chemistry Department, Jinan University, Guangzhou 510632 (China); Zhao, Hongxia [Chemistry Department, Jinan University, Guangzhou 510632 (China); Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510090 (China); Chen, Yong [Institute for Advanced Study, Nanchang University, Nanchang, Jiangxi 330031 (China); Huang, Xun [Chemistry Department, Jinan University, Guangzhou 510632 (China); Ma, Shuyuan [Chemistry Department, Jinan University, Guangzhou 510632 (China); The First Affiliated Hospital, Jinan University, Guangzhou 510632 (China); Ye, Hongyan [Chemistry Department, Jinan University, Guangzhou 510632 (China); Cai, Jiye, E-mail: tjycai@jnu.edu.cn [Chemistry Department, Jinan University, Guangzhou 510632 (China)

2010-01-22

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

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

International Nuclear Information System (INIS)

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

2010-01-01

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

Grape (Vitis vinifera) extracts protects against radiation-induced oxidative stress in human erythrocyte (RBC)

International Nuclear Information System (INIS)

Ghosh, Subhashis

2016-01-01

Ionizing radiation (IR) causes oxidative stress through the overwhelming generation of reactive oxygen species (ROS) in the living cells leading further to the oxidative damage to biomolecules. Grapes (Vitis vinifera) contain several bioactive phytochemicals and are the richest source of antioxidant. In this study, we investigated the radioprotective actions of the grape extracts of two different cultivars, including the Thompson seedless (green) and Kishmish chorni (black) in human erythrocytes. Pretreatment with grape extracts attenuates oxidative stress induced by 4 Gy-radiation in human erythrocytes in vitro. These results suggest that grape extract serve as a potential source of natural antioxidants against the IR-induced oxidative stress and also inhibit apoptosis. Furthermore, the protective action of grape depends on the source of extract (seed, skin or pulp) and type of the cultivars. Effects of grape extracts of different cultivars on protein content, Thiobarbituric acid reactive substances (TBARS) level, reduced glutathione (GSH) content and activities of Catalase, Nitrite, GST, GR in human erythrocytes against -radiation exposure at a dose of 4 Gy are investigated. The grape extracts did not appear to alter the viability of human erythrocytes. Exposure of erythrocytes to the -irradiation at a dose of 4 Gy significantly increased the extent of formation of TBARS, while decreased the level of GSH and activities of CAT, GSSG , GST, GR in the erythrocytes as compared to the non-irradiated control counterparts. This was significantly attenuated by the pretreatment with the grape seed extracts (p<0.001) and significantly with the skin extracts (p<0.05) compared to the ionizing radiation exposed group. Moreover, protection offered by the seed extracts was found significantly better than that was offered by the pulp extract of the same cultivar. In conclusion, our results suggested that the grape extracts significantly attenuated IR induced oxidative stress and

Thioredoxin 1 in Prostate Tissue Is Associated with Gleason Score, Erythrocyte Antioxidant Enzyme Activity, and Dietary Antioxidants

Directory of Open Access Journals (Sweden)

Terrence M. Vance

2015-01-01

Full Text Available Background. Prostate cancer is the most common noncutaneous cancer and second leading cause of cancer-related mortality in men in the US. Growing evidence suggests that oxidative stress is involved in prostate cancer. Methods. In this study, thioredoxin 1 (Trx 1, an enzyme and subcellular indicator of redox status, was measured in prostate biopsy tissue from 55 men from the North Carolina-Louisiana Prostate Cancer Project. A pathologist blindly scored levels of Trx 1. The association between Trx 1 and the Gleason score, erythrocyte antioxidant enzyme activity, and dietary antioxidant intake was determined using Fisher’s exact test. Results. Trx 1 levels in benign prostate tissue in men with incident prostate cancer were positively associated with the Gleason score (P=0.01 and inversely associated with dietary antioxidant intake (P=0.03. In prostate cancer tissue, Trx 1 levels were associated with erythrocyte glutathione peroxidase activity (P=0.01. No association was found for other erythrocyte enzymes. Greater Gleason score of malignant tissue corresponds to a greater difference in Trx 1 levels between malignant and benign tissue (P=0.04. Conclusion. These results suggest that the redox status of prostate tissue is associated with prostate cancer grade and both endogenous and exogenous antioxidants.

Effects of Red Wine Tannat on Oxidative Stress Induced by Glucose and Fructose in Erythrocytes in Vitro

Science.gov (United States)

Pazzini, Camila Eliza Fernandes; Colpo, Ana Ceolin; Poetini, Márcia Rósula; Pires, Cauê Ferreira; de Camargo, Vanessa Brum; Mendez, Andreas Sebastian Loureiro; Azevedo, Miriane Lucas; Soares, Júlio César Mendes; Folmer, Vanderlei

2015-01-01

The literature indicates that red wine presents in its composition several substances that are beneficial to health. This study has investigated the antioxidant effects of Tannat red wine on oxidative stress induced by glucose and fructose in erythrocytes in vitro, with the purpose to determine some of its majoritarian phenolic compounds and its antioxidant capacity. Erythrocytes were incubated using different concentrations of glucose and fructose in the presence or absence of wine. From these erythrocytes were determined the production of thiobarbituric acid reactive species (TBARS), glucose consumption, and osmotic fragility. Moreover, quantification of total phenolic, gallic acid, caffeic acid, epicatechin, resveratrol, and DPPH scavenging activity in wine were also assessed. Red wine showed high levels of polyphenols analyzed, as well as high antioxidant potential. Erythrocytes incubated with glucose and fructose had an increase in lipid peroxidation and this was prevented by the addition of wine. The wine increased glucose uptake into erythrocytes and was able to decrease the osmotic fragility of erythrocytes incubated with fructose. Altogether, these results suggest that wine leads to a reduction of the oxidative stress induced by high concentrations of glucose and fructose. PMID:26078708

Spin labelling of human erythrocytes with nitroxide radicals

International Nuclear Information System (INIS)

Chagalj, C.; DePaoli, T.C.P.; Hager, A.A.; Palaoro, L.A.; Rubin de Celis, E.; Farach, H.A.; Poole, C.P. jr

1984-01-01

Human erythrocytes were labelled with nitroxide, the spin label SYNVAR 101, under various experimantal conditions. A study was made of the influence of antireductants on the labelling efficiency and the kinetics of the radical decay during the labelling process

Borderline maintenance of erythrocyte 2,3-diphosphoglycerate concentrations in normoxic type 1 (insulin dependent) diabetic subjects.

Science.gov (United States)

Story, C J; Roberts, A P; Ryall, R G

1986-02-01

Erythrocyte 2,3-diphosphoglycerate and haemoglobin A1c concentrations were measured in 26 clinically normoxic patients with type 1 (insulin dependent) diabetes mellitus. The concentration of 2,3-diphosphoglycerate theoretically required to maintain normal erythrocyte oxygen delivery function in each subject was calculated and compared with the measured concentrations. In the majority of diabetic patients 2,3-diphosphoglycerate concentrations were sufficient to keep the erythrocyte oxygen dissociation curve within the normal range under otherwise normal blood conditions. There was, however, a minority of patients in which this was not true. It is concluded that the increased erythrocyte 2,3-diphosphoglycerate concentrations in clinically normoxic diabetic subjects are generally less than compensatory for the effect of haemoglobin A1c formation on the haemoglobin-oxygen dissociation curve.

Can Spirulina maxima reduce the mutagenic potential of sibutramine?

Science.gov (United States)

Araldi, R P; Santos, N P; Mendes, T B; Carvalho, L B; Ito, E T; de-Sá-Júnior, P L; Souza, E B

2015-12-28

The worldwide obesity pandemic requires the use of anti-obesity drugs. Sibutramine is an anti-obesity drug that has been used worldwide but is indiscriminately consumed in Brazil. Several studies have demonstrated that sibutramine promotes weight loss and weight maintenance, but several side effects have been associated with its systematic consumption. For this reason, sibutramine was withdrawn from the European and American markets, but still remains legal for use in Brazil. Studies have shown that a 5-10% reduction in body weight results in outstanding health benefits for obese patients. However, in order to promote significant weight loss, it is necessary to use sibutramine for at least 2 years. This long-term exposure has carcinogenic potential, as sibutramine causes DNA damage. Thus, this study evaluated the in vivo mutagenic potential of sibutramine alone (5, 7, 10, 15, and 20 mg/kg) and in association with Spirulina maxima (150 and 300 mg/kg), a cyanobacterium with antioxidant potential, using the polychromatic erythrocyte micronucleus test. Our results reinforced the mutagenic potential of sibutramine alone, which showed a time-dependent action. Combinatory treatments with S. maxima were not able to reduce the genotoxicity of sibutramine. These results were confirmed in vitro with the cytokinesis-blocked micronucleus test. In conclusion, our data showed that new alternative anti-obesity treatments are needed since the consumption of sibutramine can increase the risk of cancer in overweight patients.

Correlation between the results of in vitro and in vivo chromosomal damage tests in consideration of exposure levels of test chemicals.

Science.gov (United States)

Yamamura, Eiji; Aruga, Chinami; Muto, Shigeharu; Baba, Nobuyuki; Uno, Yoshifumi

2018-01-01

We examined the correlation between the results of in vitro and in vivo chromosomal damage tests by using in-house data of 18 pharmaceutical candidates that showed positive results in the in vitro chromosomal aberration or micronucleus test using CHL/IU cells, and quantitatively analyzed them especially in regard to exposure levels of the compounds. Eight compounds showed that the exposure levels [maximum plasma concentration (C max ) and AUC 0-24h ] were comparable with or higher than the in vitro exposure levels [the lowest effective (positive) concentration (LEC) and AUC vitro  = LEC (μg/mL) × treatment time (h)]. Among them, 3 compounds were positive in the in vivo rodent micronucleus assays using bone marrow cells. For 2 compounds, cytotoxicity might produce false-positive results in the in vitro tests. One compound showed in vitro positive results only in the condition with S9 mix which indicated sufficient concentration of unidentified active metabolite(s) might not reach the bone marrow to induce micronuclei. These facts suggested that the in vivo exposure levels being equal to or higher than the in vitro exposure levels might be an important factor to detect in vivo chromosomal damage induced by test chemicals.

Effects of flaxseed oil on anti-oxidative system and membrane deformation of human peripheral blood erythrocytes in high glucose level.

Science.gov (United States)

Yang, Wei; Fu, Juan; Yu, Miao; Huang, Qingde; Wang, Di; Xu, Jiqu; Deng, Qianchun; Yao, Ping; Huang, Fenghong; Liu, Liegang

2012-07-08

The erythrocyte membrane lesion is a serious diabetic complication. A number of studies suggested that n-3 fatty acid could reduce lipid peroxidation and elevate α- or γ-tocopherol contents in membrane of erythrocytes. However, evidence regarding the protective effects of flaxseed oil, a natural product rich in n-3 fatty acid, on lipid peroxidation, antioxidative capacity and membrane deformation of erythrocytes exposed to high glucose is limited. Human peripheral blood erythrocytes were isolated and treated with 50 mM glucose to mimic hyperglycemia in the absence or presence of three different doses of flaxseed oil (50, 100 or 200 μM) in the culture medium for 24 h. The malondialdehyde (MDA) and L-glutathione (GSH) were measured by HPLC and LC/MS respectively. The phospholipids symmetry and membrane fatty acid composition of human erythrocytes were detected by flow cytometry and gas chromatograph (GC). The morphology of human erythrocyte was illuminated by ultra scanning electron microscopy. Flaxseed oil attenuated hyperglycemia-induced increase of MDA and decrease of GSH in human erythrocytes. Human erythrocytes treated with flaxseed oil contained higher C22:5 and C22:6 than those in the 50 mM glucose control group, indicating that flaxseed oil could reduce lipid asymmetric distribution and membrane perturbation. The ultra scanning electron microscopy and flow cytometer have also indicated that flaxseed oil could protect the membrane of human erythrocytes from deformation at high glucose level. The flaxseed oil supplementation may prevent lipid peroxidation and membrane dysfunction of human erythrocytes in hyperglycemia.

Uranium ({sup 238}U)-induced ROS and cell cycle perturbations, antioxidant responses and erythrocyte nuclear abnormalities in the freshwater iridescent shark fish Pangasius sutchi

Energy Technology Data Exchange (ETDEWEB)

Annamalai, Sathesh Kumar; Arunachalam, Kantha Deivi, E-mail: kanthad.arunachalam@gmail.com

2017-05-15

micronucleus frequencies in erythrocytes with greater exposure time. The higher the concentration of {sup 238}U is, the greater is the effect observed, suggesting a close relationship between accumulation and toxicity. A possible ROS-mediated {sup 238}U toxicity mechanism and antioxidant responses have been proposed.

Erythrocytes in alternating electric fields

International Nuclear Information System (INIS)

Morariu, V.V.; Chifu, A.; Simplaceanu, T.; Frangopol, P.T.

1983-02-01

The elastic and inelastic deformation of erythrocytes induced by alternating fields and the suggestion that moderate field intensities (1.2 kV/cm) when continuously applied can cause lysis by a different mechanism compared to the action of short intense field pulses is presented. The different experimental conditions can be used to approach various properties of the membrane such as those related to the dielectric polarization of the membrane or to the interfacial polarization, leading to the inelastic deformation of the cells. (authors)

Effect of fluorozis on the erythrocyte antioxidant enzyme activity levels

International Nuclear Information System (INIS)

Akdogan, M.; YiImaz, D.; Yontem, M.; Kalei, S.; Kilic, I.

2011-01-01

While the flourine level of (drinking) water was higher than normal ranges in the center of Isparta region before 1995 year, this problematic situation is solved in later years. (However) the individuals who are staying in Yenice district are still expose to high levels of fluorine because of the usage of Andik spring water (3.8 mg/L flour level) as drinking water. In this study we aimed to investigate the harmful effect of floride on human erythrocytes via antioxidant defence system and lipid peroxidation. Therefore, we studied the activities of erythrocyte antioxidant enzymes such as Superoxide Dismutase (SOD), Glutathione Peroxidase (GSH-Px) and Catalase (CAT), and the level of erythrocyte Glutathione (GSH), thiobarbituric acid reactive substance (TBARS) and the level of urine floride in high floride exposed people (children, adult and elderly). The activities of SOD, GSH-Px and CAT and the level of GSH, TBARS and urine floride were higher in 3.8 mg/L floride exposed children (Group II) than 0.8 mg/L floride exposed control children (Group I) (p 0.05). The activities of SOD, GSH-Px and CAT were lower and the levels of TBARS and urine floride were higher in 3.8 mg/L floride exposed elderly people (Group VI) than 0.8 mg/L floride exposed control elderly people (Group V) (p 0.05). As a result we thought that increased SOD, GSH-Px and CAT activities in floride exposed children and adult people, decreased activities of these enzymes in floride exposed elderly people, and increased TBARS in all groups may indicate floride caused oxidative damage in erythrocytes. (author)

Antioxidant capacity of Ugni molinae fruit extract on human erythrocytes: an in vitro study.

Science.gov (United States)

Suwalsky, Mario; Avello, Marcia

2014-08-01

Ugni molinae is an important source of molecules with strong antioxidant activity widely used as a medicinal plant in Southern Chile-Argentina. Total phenol concentration from its fruit extract was 10.64 ± 0.04 mM gallic acid equivalents. Analysis by means of HPLC/MS indicated the presence of the anthocyanins cyanidin and peonidin, and the flavonol quercitin, all in glycosylated forms. Its antioxidant properties were assessed in human erythrocytes in vitro exposed to HClO oxidative stress. Scanning electron microscopy showed that HClO induced an alteration in erythrocytes from a normal shape to echinocytes; however, this change was highly attenuated in samples containing U. molinae extracts. It also had a tendency in order to reduce the hemolytic effect of HClO. In addition, X-ray diffraction experiments were performed in dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine bilayers, classes of lipids preferentially located in the outer and inner monolayers, respectively, of the human erythrocyte membrane. It was observed that U. molinae only interacted with DMPC. Results by fluorescence spectroscopy on DMPC large unilamellar vesicles and isolated unsealed human erythrocyte membranes also showed that it interacted with the erythrocyte membrane and DMPC. It is possible that the location of U. molinae components into the membrane outer monolayer might hinder the diffusion of HClO and of free radicals into cell membranes and the consequent decrease of the kinetics of free radical reactions.

Biomonitoring of genotoxic risk in radar facility workers: comparison of the comet assay with micronucleus assay and chromatid breakage assay

International Nuclear Information System (INIS)

Garaj-Vrhovac, V.; Kopjar, N.

2003-01-01

Genotoxic risks of occupational exposure in a radar facility were evaluated by using alkaline comet assay, micronucleus assay and chromatid breakage assay on peripheral blood leukocytes in exposed subjects and corresponding controls. Results show that occupational exposure to microwave radiation correlates with an increase of genome damage in somatic cells. The levels of DNA damage in exposed subjects determined by using alkaline comet assay were increased compared to control and showed interindividual variations. Incidence of micronuclei was also significantly increased compared to baseline control values. After short exposure of cultured lymphocytes to bleomycin, cells of occupationally exposed subjects responded with high numbers of chromatid breaks. Although the level of chromosome damage generated by bleomycin varied greatly between individuals, in exposed subjects a significantly elevated number of chromatid breaks was observed. Our results support data reported in literature indicating that microwave radiation represents a potential DNA-damaging hazard. Alkaline comet assay is confirmed as a sensitive and highly reproducible technique for detection of primary DNA damage inflicted in somatic cells. Micronucleus assay was confirmed as reliable bio-markers of effect and chromatid breakage assay as sensitive bio-marker of individual cancer susceptibility. The results obtained also confirm the necessity to improve measures and to perform accurate health surveillance of individuals occupationally exposed to microwave radiation

Deformabilidade eritrocitária na anemia ferropriva Erythrocyte deformability in iron deficiency

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Giuseppina M. Patavino

2006-12-01

Full Text Available A deformabilidade é a característica que permite ao eritrócito normal de 7 a 8 micrômetros (µm circular por capilares de até 3 µm de diâmetro. Esse fenômeno depende da geometria celular, da viscosidade interna e de propriedades visco-elásticas da membrana eritrocitária. Dentre as técnicas de estudo da deformabilidade eritrocitária (DE, como aspiração por micropipeta, filtração e reoscopia, destaca-se a ectacitometria. Esta técnica utiliza um viscosímetro de fluxo laminar no qual as modificações de forma dos eritrócitos são monitoradas continuamente por um feixe de raio laser, processadas por microcomputador, gerando o "Índice de Deformabilidade" (ID, que mede a eliptocitogênese dos eritrócitos quando submetidos a uma força denominada "shear stressl". Alterações de DE foram descritas em diversas situações, como em anemias hemolíticas hereditárias ou auto-imunes. Na anemia ferropriva, os trabalhos são controversos. O presente estudo avalia a DE em 21 pacientes portadores de anemia ferropriva, utilizando a ectacitometria. Os resultados obtidos a partir do ID demonstram DE diminuída nesses doentes, quando comparada ao grupo controle (pDeformability allows the 7 to 8 µm red cell to cirDeformability allows the 7- to 8-µm red blood cells to circulate through capillaries of 3 µm. This phenomenon depends on cellular geometry, internal viscosity and viscoelastic properties of the membrane. Among the various techniques of erythrocyte deformability analysis, such as micropipette aspiration, filtration and reoscopy, we chose ektacytometry. This technique uses a laminar flow viscometry, where red blood cell shape changes are continuously monitored by laser, processed by a computer, generating the "Deformability Index", which shows the elliptocytogenesis of the erythrocyte under "shear stressl" force. Erythrocyte deformability has been described in a number of situations like hereditary or autoimmune hemolytic anemia. In

A gasometric method to determine erythrocyte catalase activity

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A.J.S. Siqueira

1999-09-01

Full Text Available We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen produced as a result of hydrogen peroxide decomposition in a system where enzyme and substrate are separated in a special reaction test tube connected to a manometer and the reagents are mixed with a motor-driven stirrer. The position of the reagents in the test tube permits the continuous measurement of oxygen evolution from the time of mixing, without the need to stop the reaction by the addition of acid after each incubation time. The enzyme activity is reported as KHb, i.e., mg hydrogen peroxide decomposed per second per gram of hemoglobin (s-1 g Hb-1. The value obtained for catalase activity in 28 samples of hemolyzed human blood was 94.4 ± 6.17 mg H2O2 s-1 g Hb-1. The results obtained were precise and consistent, indicating that this rapid, simple and inexpensive method could be useful for research and routine work.

Circulating erythrocyte-derived microparticles are associated with coagulation activation in sickle cell disease

Science.gov (United States)

van Beers, Eduard J.; Schaap, Marianne C.L.; Berckmans, René J.; Nieuwland, Rienk; Sturk, Augueste; van Doormaal, Frederiek F.; Meijers, Joost C.M.; Biemond, Bart J.

2009-01-01

Background Sickle cell disease is characterized by a hypercoagulable state as a result of multiple factors, including chronic hemolysis and circulating cell-derived microparticles. There is still no consensus on the cellular origin of such microparticles and the exact mechanism by which they may enhance coagulation activation in sickle cell disease. Design and Methods In the present study, we analyzed the origin of circulating microparticles and their procoagulant phenotype during painful crises and steady state in 25 consecutive patients with sickle cell disease. Results The majority of microparticles originated from platelets (GPIIIa,CD61) and erythrocytes (glycophorin A,CD235), and their numbers did not differ significantly between crisis and steady state. Erythrocyte-derived microparticles strongly correlated with plasma levels of markers of hemolysis, i.e. hemoglobin (r=−0.58, pmicroparticles (r=0.63, p0.05). The extent of factor XI inhibition was associated with erythrocyte-derived microparticles (r=0.50, p=0.023). Conclusions We conclude that the procoagulant state in sickle cell disease is partially explained by the factor XI-dependent procoagulant properties of circulating erythrocyte-derived microparticles. PMID:19815831

Association of erythrocyte deformability with red blood cell distribution width in metabolic diseases and thalassemia trait.

Science.gov (United States)

Vayá, Amparo; Alis, Rafael; Suescún, Marta; Rivera, Leonor; Murado, Julian; Romagnoli, Marco; Solá, Eva; Hernandez-Mijares, Antonio

2015-01-01

Increased red blood distribution width (RDW) in anemia is related to disturbances in the cellular surface/volume ratio, usually accompanied by morphological alterations, while it has been shown in inflammatory diseases that the activity of pro-inflammatory cytokines disturbing erythropoiesis increases RDW. Recently it has been reported that higher RDW is related with decreased erythrocyte deformability, and that it could be related with the association of RDW and increased risk of cardiovascular diseases. In order to analyze the influence of morphological alterations and proinflammatory status on the relationship between RDW and erythrocyte deformability, we analyzed erythrocyte deformability along with RDW and other hematological and biochemical parameters in 36 α-thalassemia, 20 β-thalassemia, 20 δβ-thalassemia trait carriers, 61 metabolic syndrome patients and 76 morbidly obese patients. RDW correlated inversely with erythrocyte deformability in minor β-thalassemia (r =-0.530, p thalassemia is often accompanied by more marked cell-shaped perturbations than other thalassemia traits. This could be the reason for this negative association only in this setting. Higher anisocytosis seems to be associated with greater morphologic alterations (shape/volume), which reduce erythrocyte deformability. The proinflammatory profile in metabolic patients can be related to the positive association of RDW with erythrocyte deformability found in these patients. However, further research is needed to explain the mechanisms underlying this association.

Practical aspects of mutagenicity testing strategy: an industrial perspective.

Science.gov (United States)

Gollapudi, B B; Krishna, G

2000-11-20

Genetic toxicology studies play a central role in the development and marketing of new chemicals for pharmaceutical, agricultural, industrial, and consumer use. During the discovery phase of product development, rapid screening tests that require minimal amounts of test materials are used to assist in the design and prioritization of new molecules. At this stage, a modified Salmonella reverse mutation assay and an in vitro micronucleus test with mammalian cell culture are frequently used for screening. Regulatory genetic toxicology studies are conducted with a short list of compounds using protocols that conform to various international guidelines. A set of four assays usually constitutes the minimum test battery that satisfies global requirements. This set includes a bacterial reverse mutation assay, an in vitro cytogenetic test with mammalian cell culture, an in vitro gene mutation assay in mammalian cell cultures, and an in vivo rodent bone marrow micronucleus test. Supplementary studies are conducted in certain instances either as a follow-up to the findings from this initial testing battery and/or to satisfy a regulatory requirement. Currently available genetic toxicology assays have helped the scientific and industrial community over the past several decades in evaluating the mutagenic potential of chemical agents. The emerging field of toxicogenomics has the potential to redefine our ability to study the response of cells to genetic damage and hence our ability to study threshold phenomenon.

Bioassessment of the Effluents Discharged from Two Export Oriented Industrial Zones Located in Kelani River Basin, Sri Lanka Using Erythrocytic Responses of the Fish, Nile Tilapia (Oreochromis niloticus).

Science.gov (United States)

Hemachandra, C K; Pathiratne, A

2017-10-01

Complex effluents originating from diverse industrial processes in industrial zones could pose cytotoxic/genotoxic hazards to biota in the receiving ecosystems which cannot be revealed by conventional monitoring methods. This study assessed potential cytotoxicity/genotoxicity of treated effluents of two industrial zones which are discharged into Kelani river, Sri Lanka combining erythrocytic abnormality tests and comet assay of the tropical model fish, Nile tilapia. Exposure of fish to the effluents induced erythrocytic DNA damage and deformed erythrocytes with serrated membranes, vacuolations, nuclear buds and micronuclei showing cytotoxic/genotoxic hazards in all cases. Occasional exceedance of industrial effluent discharge regulatory limits was noted for color and lead which may have contributed to the observed cytotoxicity/genotoxicity of effluents. The results demonstrate that fish erythrocytic responses could be used as effective bioanalytical tools for cytotoxic/genotoxic hazard assessments of complex effluents of industrial zones for optimization of the waste treatment process in order to reduce biological impacts.

Erythrocytes labelling for to value bleeding of digestive tract in pediatrics

International Nuclear Information System (INIS)

Mora, R.

2002-01-01

The erythrocytes labelling has been facilitated by several factors: a) They are the cellular elements more abundant in the blood (5 x 10 9 / ml blood). b) They are easy to be isolated and manipulated In vitro and they are not very sensitive to the physical or chemical damages. c) They do not depend on energy or nutritious requirements as another cellular elements In vitro. d) With respect to another cells they show an easier labelling with radionuclides due to the availability of a variety of transporter mechanisms and of internal hemoglobin which is rich in active metal with multiple union sites. The erythrocytes are biconcave disks without nucleus composed by a 65% water, 32% hemoglobin and a 3% by lipids and proteins which form the stroma.The hemoglobin is the most important component of erythrocytes, it contains 4 heme groups and one globin molecule (with molecular weight of 68000) and fix iron covalently with 4 atoms of nitrogenated porfyrin. The oxygen is reversibly joined to iron. The hemoglobin does not experiment re-synthesis or degradation during its lifetime in the erythrocyte. It has been stipulated that the diagnostic applications in nuclear medicine are: a) That the radionuclide should have a high intensity of emission with an adequate energy for the image, with minimum particulate radiation and a half life time average similar to the length of the study that is carried out. b) That the radionuclide is joined firmly to the In vivo cells without altering physical and biochemical properties of the cells and their function In vitro. c) That the radionuclide once incorporated to the interior of cell must not be liberated during the study neither reused after of destruction. A quick procedure is now found available for labelling erythrocytes with 99m Tc offering a high performance and quality labelling. This is narrowly related to the 99m Tc chemistry understanding. (Author)

Lipopeptide-Induced Suicidal Erythrocyte Death Correlates with the Degree of Acylation

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Abdulla Al Mamun Bhuyan

2017-01-01

Full Text Available Background/Aims: Consequences of bacterial infection include anemia, which could result from stimulation of suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Bacterial components known to stimulate eryptosis include lipopeptides. Signaling mediating the triggering of eryptosis include increased cytosolic Ca2+ activity ([Ca2+]i, oxidative stress and cellular accumulation of ceramide. The present study aimed to define the molecular requirements for lipopeptide-induced cell membrane scrambling. Methods: Human erythrocytes were incubated for 48 hours in the absence and presence of 1 or 5 µg/ml of the synthetic lipopeptides Pam1 (lipopeptide with one fatty acid, Pam2 (lipopeptide with two fatty acids, or Pam3 (lipopeptide with three fatty acids. In the following phosphatidylserine exposure at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCF dependent fuorescence, and ceramide abundance utilizing specific antibodies. Results: Pam1 (5 µg/ml, Pam2 (5 µg/ml and Pam3 (1 and 5 µg/ml significantly increased the percentage of annexin-V-binding to erythrocytes in a dose dependent manner, which was largely independent of Ca2+. Pam1-3 increased the percentage of both, swollen and shrunken erythrocytes without significantly modifying the average forward scatter. They also increased reactive oxygen species (ROS and ceramide abundance. In all assays the effect on eryptosis increased with increasing number of fatty acids, with Pam3 showing always the strongest effect. In contrast, a comparison of the effect of Pam1-3 on TLR2 dependent immune stimulation showed that not Pam3 but Pam2 displayed the strongest activity, and that immune stimulation was triggered at much lower concentrations than eryptosis. Conclusions: Lipopeptides are not only important

Effect of Sodium Fluoride Ingestion on Malondialdehyde Concentration and the Activity of Antioxidant Enzymes in Rat Erythrocytes

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José A. Morales-González

2010-06-01

Full Text Available Fluoride intoxication has been shown to produce diverse deleterious metabolic alterations within the cell. To determine the effects of sodium fluoride (NaF treatment on malondialdehyde (MDA levels and on the activity of antioxidant enzymes in rat erythrocytes, Male Wistar rats were treated with 50 ppm of NaF or were untreated as controls. Erythrocytes were obtained from rats sacrificed weekly for up to eight weeks and the concentration of MDA in erythrocyte membrane was determined. In addition, the activity of the enzymes superoxide, dismutase, catalase, and glutathione peroxidase were determined. Treatment with NaF produces an increase in the concentration of malondialdehyde in the erythrocyte membrane only after the eight weeks of treatment. On the other hand, antioxidant enzyme activity was observed to increase after the fourth week of NaF treatment. In conclusion, intake of NaF produces alterations in the erythrocyte of the male rat, which indicates induction of oxidative stress.

PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

International Nuclear Information System (INIS)

Borbely-Kiss, I.; Koltay, E.; Laszlo, S.; Szabo, Gy.

1984-01-01

Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. (author)

PIXE elemental analysis of erythrocyte and blood plasma samples from human pregnancies

Energy Technology Data Exchange (ETDEWEB)

Borbely-Kiss, I; Koltay, E; Laszlo, S; Szabo, Gy [Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete; Goedeny, S [Orvostudomanyi Egyetem, Szeged (Hungary). Szueleszeti es Noegyogyaszati Klinika; Seif El-Nasr, S [Teachers' Coll. for Women, Samia (Kuwait)

1984-07-01

Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregnancies. 11 refs.

Design and evaluation of antimalarial peptides derived from prediction of short linear motifs in proteins related to erythrocyte invasion.

Directory of Open Access Journals (Sweden)

Alessandra Bianchin

Full Text Available The purpose of this study was to investigate the blood stage of the malaria causing parasite, Plasmodium falciparum, to predict potential protein interactions between the parasite merozoite and the host erythrocyte and design peptides that could interrupt these predicted interactions. We screened the P. falciparum and human proteomes for computationally predicted short linear motifs (SLiMs in cytoplasmic portions of transmembrane proteins that could play roles in the invasion of the erythrocyte by the merozoite, an essential step in malarial pathogenesis. We tested thirteen peptides predicted to contain SLiMs, twelve of them palmitoylated to enhance membrane targeting, and found three that blocked parasite growth in culture by inhibiting the initiation of new infections in erythrocytes. Scrambled peptides for two of the most promising peptides suggested that their activity may be reflective of amino acid properties, in particular, positive charge. However, one peptide showed effects which were stronger than those of scrambled peptides. This was derived from human red blood cell glycophorin-B. We concluded that proteome-wide computational screening of the intracellular regions of both host and pathogen adhesion proteins provides potential lead peptides for the development of anti-malarial compounds.

Complement Receptor 1 Is a Sialic Acid-Independent Erythrocyte Receptor of Plasmodium falciparum

Science.gov (United States)

2010-06-17

Sciences, Bethesda, MD, ...... 14. ABSTRACT Plasmodium falciparum is a highly lethal malaria parasite of humans. A major portion of its life cycle is...parasite of humans. A major portion of its life cycle is dedicated to invading and multiplying inside erythrocytes. The molecular mechanisms of...Complement Receptor 1 Is a Sialic Acid-Independent Erythrocyte Receptor of Plasmodium falciparum Carmenza Spadafora1,2,3, Gordon A. Awandare4

Characterization of carbonic anhydrase XIII in the erythrocytes of the Burmese python, Python molurus bivittatus.

Science.gov (United States)

Esbaugh, A J; Secor, S M; Grosell, M

2015-09-01

Carbonic anhydrase (CA) is one of the most abundant proteins found in vertebrate erythrocytes with the majority of species expressing a low activity CA I and high activity CA II. However, several phylogenetic gaps remain in our understanding of the expansion of cytoplasmic CA in vertebrate erythrocytes. In particular, very little is known about isoforms from reptiles. The current study sought to characterize the erythrocyte isoforms from two squamate species, Python molurus and Nerodia rhombifer, which was combined with information from recent genome projects to address this important phylogenetic gap. Obtained sequences grouped closely with CA XIII in phylogenetic analyses. CA II mRNA transcripts were also found in erythrocytes, but found at less than half the levels of CA XIII. Structural analysis suggested similar biochemical activity as the respective mammalian isoforms, with CA XIII being a low activity isoform. Biochemical characterization verified that the majority of CA activity in the erythrocytes was due to a high activity CA II-like isoform; however, titration with copper supported the presence of two CA pools. The CA II-like pool accounted for 90 % of the total activity. To assess potential disparate roles of these isoforms a feeding stress was used to up-regulate CO2 excretion pathways. Significant up-regulation of CA II and the anion exchanger was observed; CA XIII was strongly down-regulated. While these results do not provide insight into the role of CA XIII in the erythrocytes, they do suggest that the presence of two isoforms is not simply a case of physiological redundancy. Copyright © 2015. Published by Elsevier Inc.

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

African Journals Online (AJOL)

, dogs, rabbits, rats and mice. Encapsulation in erythrocytes drastically changes the pharmacokinetic properties of drugs in both animals and humans, enhancing liver and spleen uptake and targeting the reticulo-endothelial system (RES).

Erythrocytes and von Willebrand factor in venous thrombosis

NARCIS (Netherlands)

Smeets, M.W.J.

2018-01-01

Venous thromboembolism represents the third leading vascular disease after myocardial infarction and stroke. Erythrocytes, the most abundant cells in venous thrombi, were thought to be innocent bystanders that become tangled up in the fibrin mesh of venous thrombi. However, this thesis describes

Changes in erythrocyte ATPase activity under different pathological ...

African Journals Online (AJOL)

Changes in erythrocyte ATPase activity under different pathological conditions. Ali A Kherd, Nawal Helmi, Khadijah Saeed Balamash, Taha A Kumosani, Shareefa A AL-Ghamdi, Qari M, Etimad A Huwait, Soonham S Yaghmoor, Alaama Nabil, Maryam A AL-Ghamdi, Said S Moselhy ...

Effect of pH on molecular constitution and distribution of hemoglobin in living erythrocyte.

Science.gov (United States)

Wu, Yue; Huang, Yao-Xiong; Kang, Li-Li; Wu, Zheng-Jie; Luo, Man

2010-04-01

The molecular constitution of in situ hemoglobin (Hb) and their distribution in living erythrocyte were investigated versus pH using the technique of confocal Raman microscopy. Both Raman point spectra and line mapping measurements were performed on living erythrocytes in suspensions with pH values from 4.82 to 9.70. It was found that the Hb inside a living erythrocyte would dissociate into monomer/dimer when the cells are in low and high pH environments. In contrast to the homogeneous distribution of the Hbs in the cells in neutral suspension, there are more Hbs distributing around the cell membrane or binding to the membrane as pH increases. While in low pH, as the cell become spherical, most of the Hbs distribute to the central part of the cell. In summary, our investigation suggests that the variation of the external pH not only brings changes in the morphology and membrane structure of an erythrocyte, but also affects the constitution and distribution of its intracellular Hbs, thereby the flexibility of the cell membrane and the oxygenation ability of the Hb.

Determination of CFTR densities in erythrocyte plasma membranes using recognition imaging

International Nuclear Information System (INIS)

Ebner, Andreas; Hinterdorfer, Peter; Nikova, Dessy; Lange, Tobias; Bruns, Reimer; Oberleithner, Hans; Schillers, Hermann; Haeberle, Johannes; Falk, Sabine; Duebbers, Angelika

2008-01-01

CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-regulated chloride (Cl - ) channel that plays an important role in salt and fluid movement across epithelia. Cystic fibrosis (CF), the most common genetic disease among Caucasians, is caused by mutations in the gene encoding CFTR. The most predominant mutation, F508del, disturbs CFTR protein trafficking, resulting in a reduced number of CFTR in the plasma membrane. Recent studies indicate that CFTR is not only found in epithelia but also in human erythrocytes. Although considerable attempts have been made to quantify CFTR in cells, conclusions on numbers of CFTR molecules localized in the plasma membrane have been drawn indirectly. AFM has the power to provide the needed information, since both sub-molecular spatial resolution and direct protein recognition via antibody-antigen interaction can be observed. We performed a quantification study of the CFTR copies in erythrocyte membranes at the single molecule level, and compared the difference between healthy donors and CF patients. We detected that the number of CFTR molecules is reduced by 70% in erythrocytes of cystic fibrosis patients

Determination of CFTR densities in erythrocyte plasma membranes using recognition imaging

Energy Technology Data Exchange (ETDEWEB)

Ebner, Andreas; Hinterdorfer, Peter [Institute for Biophysics, University of Linz, A-4040 Linz (Austria); Nikova, Dessy; Lange, Tobias; Bruns, Reimer; Oberleithner, Hans; Schillers, Hermann [Institute of Physiology II, University of Muenster, D-48149 Muenster (Germany); Haeberle, Johannes; Falk, Sabine; Duebbers, Angelika [Department of Pediatrics, University Hospitals of Muenster, D-48149 Muenster (Germany)], E-mail: schille@uni-muenster.de

2008-09-24

CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-regulated chloride (Cl{sup -}) channel that plays an important role in salt and fluid movement across epithelia. Cystic fibrosis (CF), the most common genetic disease among Caucasians, is caused by mutations in the gene encoding CFTR. The most predominant mutation, F508del, disturbs CFTR protein trafficking, resulting in a reduced number of CFTR in the plasma membrane. Recent studies indicate that CFTR is not only found in epithelia but also in human erythrocytes. Although considerable attempts have been made to quantify CFTR in cells, conclusions on numbers of CFTR molecules localized in the plasma membrane have been drawn indirectly. AFM has the power to provide the needed information, since both sub-molecular spatial resolution and direct protein recognition via antibody-antigen interaction can be observed. We performed a quantification study of the CFTR copies in erythrocyte membranes at the single molecule level, and compared the difference between healthy donors and CF patients. We detected that the number of CFTR molecules is reduced by 70% in erythrocytes of cystic fibrosis patients.

Encapsulation of interleukin-2 in murine erythrocytes and subsequent deposition in mice receiving a subcutaneous injection

International Nuclear Information System (INIS)

DeLoach, J.R.; Andrews, K.; Sheffield, C.L.

1988-01-01

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 [ 35 S]IL-2 was detectable in a number of tissues 3 days after injection

Regulation of hemoglobin AIc formation in human erythrocytes in vitro. Effects of physiologic factors other than glucose.

OpenAIRE

Smith, R J; Koenig, R J; Binnerts, A; Soeldner, J S; Aoki, T T

1982-01-01

The formation of hemoglobin AIc was studied in intact human erythrocytes in vitro. Satisfactory methods were developed for maintaining erythrocytes under physiologic conditions for greater than 8 d with less than 10% hemolysis. Hemoglobin AIc levels were determined chromatographically on erythrocyte hemolysates after removal of reversible components by incubation for 6 h at 37 degree C. Hemoglobin AIc concentration was found to increase linearly with time during 8 d of incubation. The rate of...

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 ...

Erythrocytes 125I-Insulin Binding Studies in Viral Hepatitis and Schistosomiasis Patients

International Nuclear Information System (INIS)

Ahmed, A.M.

2003-01-01

The present study aims to evaluate the alterations of insulin binding sites in human erythrocytes in patients with chronic viral B and C hepatitis and in schistosomiasis. Fifty men with ages ranged from 20-45 years were diagnosed into five groups; hepatitis B virus, hepatitis C virus, mixed hepatitis B and C, schistosomiasis and normal healthy volunteers as a control group. Biochemical analyses as erythrocyte insulin radioreceptor, plasma insulin estimation, fasting and post prandial blood glucose levels and liver function tests were performed. The results revealed significant decrease in insulin binding sites/cell in patients with hepatitis C virus, mixed B and C viruses and in schistosomiasis compared to the control group. There were significant increase in fasting plasma glucose levels in groups of hepatitis C virus mixed B and C viruses, while there were highly significant increase in post prandial plasma glucose levels in patients with mixed B and C viruses and in schistosomiasis groups compared to the normal control. Also, fasting plasma insulin levels were significantly elevated in groups of hepatitis C mixed B and C viruses and in schistosomiasis group. The obtained results revealed the importance of laboratory follow up of glucose and insulin levels in patients with chronic liver diseases

Dietary nucleotide supplementation raises erythrocyte 2, 3-diphosphoglycerate concentration in neonatal rats.

Science.gov (United States)

Scopesi, F; Verkeste, C M; Paola, D; Gazzolo, D; Pronzato, M A; Bruschettini, P L; Marinari, U M

1999-03-01

The present study was designed to test if dietary intake of nucleotides increases erythrocyte 2,3-diphosphoglycerate (2,3-DPG) in neonatal rats. To this end, rat pups were fed a nucleotide-supplemented formula (S, n = 14) from d 9 until d 16 after birth. The results were compared with those obtained from a group of breast-fed pups (C, n = 14) and a group of pups artificially fed with nucleotide-free formula (NS, n = 14). Neonatal weight, 2,3-DPG concentration, hematocrit (Hct) and hemoglobin concentration (Hb) were determined before the experiment (d 9) and after 7 d of treatment (d 16). In all groups, 2,3-DPG concentration was greater at d 16 than d 9, and the increase was greater in the S group than in the NS group. Alterations in neonatal weight, Hct and Hb concentration did not differ among the groups. On d 16 the 2, 3-DPG/Hb ratio, reflecting the affinity of hemoglobin for oxygen, was significantly higher in the C and S groups than in the NS group. We conclude that in neonatal rats, dietary nucleotides increase erythrocyte 2,3-DPG concentration. Studies need to be conducted in humans to assess the effect of this increase on both neonatal peripheral hemodynamics and metabolism in this species.

Effects of whole-body gamma irradiation on oxygen transport by rat erythrocytes

International Nuclear Information System (INIS)

Thiriot, Christian; Kergonou, J.F.; Rocquet, Guy; Allary, Michel; Saint-Blancard, Jacques

1982-01-01

In this work, we studied the influence of whole-body gamma irradiation (8 Gy) upon oxygen transport by erythrocytes, through the erythrocyte count and related parameters, and through the factors affecting the oxygen affinity of hemoglobin. The oxygen affinity of hemoglobin is increased from day D + 5 after irradiation, and a severe erythropenia develops from day D + 8. These modifications probably result in tissue hypoxia via diminished oxygen transport from lungs to tissues, and decreased oxygen release from oxyhemoglobin in tissues

Influence of the use of statin on the stability of erythrocyte membranes in multiple sclerosis.

Science.gov (United States)

de Freitas, Mariana Vaini; de Oliveira, Marcela Ramos; dos Santos, Diogo Fernandes; de Cássia Mascarenhas Netto, Rita; Fenelon, Sheila Bernardino; Penha-Silva, Nilson

2010-02-01

Multiple sclerosis (MS) probably occurs by oxidative, inflammatory and autoimmune mechanisms. This study investigated the influence of statin on the stability of erythrocyte membranes in MS patients. The population was composed of one group with simvastatin therapy (20 mg/day), another group without statin therapy and a healthy control group. The stability of erythrocytes was evaluated by the half-transition points, H(50) and D(50), obtained from the curves of hemolysis induced by hypotonic shock and ethanol action, respectively. Erythrocytes of MS patients were less stable against lysis by both chaotropes. This behavior may be merely a consequence of the lifestyle of MS patients or it may be intrinsically associated with the conjunct of factors responsible for the development of the disease. The use of statin by MS patients was associated with lower levels of LDL and total cholesterol, as expected, and with higher stability of erythrocytes against ethanol compared to the values of untreated MS patients.

Uranium ("2"3"8U)-induced ROS and cell cycle perturbations, antioxidant responses and erythrocyte nuclear abnormalities in the freshwater iridescent shark fish Pangasius sutchi

International Nuclear Information System (INIS)

Annamalai, Sathesh Kumar; Arunachalam, Kantha Deivi

2017-01-01

Highlights: • Exposure to "2"3"8U deteriorated the antioxidant defenses like SOD, CAT and LPO. • Flow cytometric analysis revealed the increase in G2/M phase and S phase. • Micronucleus frequencies increased with Increased "2"3"8U exposure and time. • Exposure to waterborne "2"3"8U induces both chemical and radiotoxicity in P. sutchi. • ROS-mediated "2"3"8U toxic mechanism and the antioxidant responses has been proposed. - Abstract: The strategic plan of this study is to analyze any possible radiological impact on aquatic organisms from forthcoming uranium mining facilities around the Nagarjuna Sagar Dam in the future. The predominantly consumed and dominant fish species Pangasius sutchi, which is available year-round at Nagarjuna Sagar Dam, was selected for the study. To comprehend the outcome and to understand the mode of action of "2"3"8U, the fish species Pangasius sutchi was exposed to ¼ and ½ of the LC_5_0 doses of waterborne "2"3"8U in a static system in duplicate for 21 days. Blood and organs, including the gills, liver, brain and muscles, were collected at different time periods—0 h, 24 h, 48 h, 72 h, 96 h, 7, days 14 days and 21 days—using ICP-MS to determine the toxic effects of uranium and the accumulation of "2"3"8U concentrations. The bioaccumulation of "2"3"8U in P. sutchi tissues was dependent on exposure time and concentration. The accumulation of uranium was, in order of magnitude, measured as gills > liver > brain > tissue, with the highest accumulation in the gills. It was observed that exposure to "2"3"8U significantly reduced antioxidant enzymes such as superoxide dismutase, catalase, and lipid peroxidase. The analysis of DNA fragmentation by comet assay and cell viability by flow cytometry was performed at different time intervals. DNA histograms by flow cytometry analysis revealed an increase in the G2/M phase and the S phase. The long-term "2"3"8U exposure studies in fish showed increasing micronucleus frequencies in