Wyniki wyszukiwania - Biblioteka Nauki

1

The criteria of life and aging from a molecular viewpoint. The role of protein aggregation in the process of aging

100%

Spólnik P. , Konieczny L. , Piekarska B. , Rybarska J. , Stopa B. , Zemanek G.

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2011

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tom Vol. 7, no. 1

23--30

EN

Biological knowledge is expanding rapidly, delving deep into nature’s mechanisms. However, the essence of life as a molecular process still remains unclear. Organized and independently operating biological systems are commonly thought to be living. Unfortunately, these characteristics are too general and altogether insufficient to accurately delimit the boundaries of life. The problem of the relation of many primitive biological entities to the living world is still open. The properties of self-dependent biological systems clearly derive from their highly organized automatic nature. The comparative analysis of genomes of primitive biological organisms seems to be the most promising approach, which may eventually lead to the understanding of life at the molecular level and its definition. The erythrocyte appears to be of particular interest as a model of a living system that is at a boundary. Its biological origin, automatically controlled metabolism, and programmed death sharply defined in time qualify it as the living structure, even though it is completely deprived of a genetic apparatus. However, its membership among living systems seems to be well-founded. Protein aggregation is one of the common characteristics of aging. It is a consequence of abnormalities of protein structure induced by destructive actions but also by abnormalities of synthesis. Aggregation of membrane proteins probably affects the activity of certain enzymes or transport proteins, which are important as energy providers for aging erythrocytes. After the erythrocyte has passed through the vascular system a given number of times, it is not able to undergo a certain set of indispensable metabolic rearrangements. A living thing is then a form of animated nature which has the features of independence as a result of automation and possesses its own compatible with nature program of action which is time-limited beforehand.

2

Body mass dependence of the haemoglobin content to surface area ratio of avian erythrocytes

100%

Kostelecka-Myrcha A. , Cholostiakow-Gromek J.

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nr 2

EN

Data from 75 bird species weighing between 6 g and > 16 kg confirmed a supposition that the amount of haemoglobin per unit surface area of erythrocyte was not dependent on body mass. It showed a constancy across the range reflecting adjustment of the total surface area of erythrocytes in relation to blood haemoglobin concentration. This conclusion is based on an inverse correlation between the numbers and sizes of red blood cells.

PL

Zbadano zależności wartości wskaźników czerwonokrwinkowych od masy ciała ptaków. Do analizy tej włączono dane własne, uzyskane we wcześniejszych badaniach (Kostelecka-Myrcha et al. 1993) i dostępne dane literaturowe. Ogółem zebrano informacje dla 75 gatunków ptaków, o masie ciała od 6 g do ponad 16 kg. Poszczególne zależności scharakteryzowano za pomocą współczynników korelacji i regresji krzywoliniowych. Stwierdzono, że koncentracja hemoglobiny (Hb, Fig. 1) i liczba erytrocytów w 1 mm³ krwi (Fig. 2) zmniejszają się statystycznie istotnie ze wzrostem masy ciała ptaków, podczas gdy wielkość tych krwinek wzrasta (Fig. 3). Bardzo intensywne zmniejszanie się liczby erytrocytów w jednostce objętości krwi powoduje statystycznie istotne zmniejszanie się wartości hematokrytu (Fig. 4) i sumarycznej powierzchni erytrocytów (TSAE, Fig. 5). Zmiany wielkości tej powierzchni przebiegają wprost proporcjonalnie do zmian koncentracji Hb i dlatego stosunek Hb/TSAE nie zależy od masy ciała ptaków (Fig. 6). Jego średnia wartość wynosi 0.52 ± 0.09 pg μm⁻². Nie różni się ona statystycznie istotnie od wcześniej otrzymanej średniej dla 564 osobników różnych gatunków ptaków, przebadanych w zależności od wieku piskląt, sezonu roku i masy ciała, w wąskim zakresie jej zmienności — od 6 g do 167 g (Kostelecka-Myrcha 1997). Przedstawiona analiza potwierdza więc przypuszczenie z 1997 roku (ibidem), że ilość hemoglobiny przypadająca na jednostkę powierzchni erytrocytów (Hb/TSAE) jest u ptaków stała, i że stałość ta jest wynikiem dostosowywania się wielkości TSAE do koncentracji Hb. U podstaw tego ważnego mechanizmu, zapewniającego zawsze pełne wysycenie hemoglobiny tlenem, leży ujemna korelacja między liczbą a wielkością erytrocytów.

3

Deformation-enhanced fluctuations of the erythrocyte's spectrin-actin nodes and relation to single molecule measures of spectrin unfolding

100%

Lee J. C. M. , Discher D. E.

Cellular and Molecular Biology Letters

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2001

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tom 06

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nr 2

4

Induction and decay of thermotolerance in human erythrocytes

100%

Rogozinska M. , Koter M.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

5

Overexpression of 4.1R disturbs microtubule organization

100%

Perez-Ferreiro C. M. , Luque C. M. , Perez-Gonzales A. , Sendino E. , Correas I.

Cellular and Molecular Biology Letters

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2001

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tom 06

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nr 2

6

The effect of polyene antibiotic filipin on pig red blood cells

100%

Knopik-Skrocka A. , Klafaczynska A. , Bielawski J.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

7

Morphological transformations in human erythrocytes incubated with phenols

100%

Bukowska B. , Goszczynska K. , Duda W.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

8

No increase of phosphatidylserine exposure accompanying the increased membrane fluidity in erythrocytes of ataxia telangiectasia gene [ATM] carriers

100%

Rybczynska M. , Kaczmarek J. , Pawlak A. L.

Cellular and Molecular Biology Letters

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1998

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tom 03

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nr 2

9

Spiculated red blood cells induced by intercalation of amphiphiles

100%

Iglic A. , Kralj-Iglic V. , Hagerstrand H.

Cellular and Molecular Biology Letters

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1998

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tom 03

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nr 2

10

Stomatocytosis and stomatin

100%

Stewart G. W. , Coles S. E.

Cellular and Molecular Biology Letters

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1998

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tom 03

|

nr 2

11

The effect of physical exercise on glutathione-dependent erythrocytes' antioxidant system

100%

Hubner-Wozniak E. , Lutoslawska G.

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tom 07

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nr 6

12

Transport of organic anions by multidrug resistance-associated protein in the erythrocyte.

88%

Rychlik B. , Pułaski Ł. , Sokal A. , Soszyński M. , Bartosz G.

Acta Biochimica Polonica

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2000

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tom 47

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nr 3

763-772

EN

The active transport of oxidized glutathione and glutathione S-conjugates has been demonstrated for the first time in erythrocytes and this cell remained the main subject of research on the "glutathione S-conjugate pump" for years. Further studies identified the "glutathione S-conjugate pump" as multidrug resistance-associated protein (MRP). Even though cells overexpressing MRP and isolated MRP provide useful information on MRP structure and function, the erythrocyte remains an interesting model cell for studies of MRP1 in its natural environment, including the substrate specificity and ATPase activity of the protein.

13

The Changes of Elongation Index of erythrocytes caused by storage of blood at low temperature

88%

Dylong I. , Dolibog P. , Mularz T. , Młynarski J. , Grzegorczyn S.

Polish Journal of Medical Physics and Engineering

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2023

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tom Vol. 29, Iss. 1

35--41

EN

Introduction: An important parameter characterizing the ability of erythrocytes to deform depending on the blood flow conditions is the Elongation Index (EI), and it is a parameter defined by the shape of the erythrocyte obtained as a diffraction pattern of erythrocytes at different values of shear stresses. Material and methods: EI measurements at different shear stress were performed by Laser-assisted Optical Rotational Cell Analyzer (LORRCA) for erythrocytes derived from Tissue Bank in Katowice. Measurements were performed immediately after receiving them from Tissue Bank and after 2, 9, and 28 days of storage of samples at the temperature of 4°C in solution with the anticoagulant. Results: An increase in the erythrocytes Elongation Index in the first 9 days of storing samples at low temperatures was observed in the entire range of applied shear stresses. This indicates an increase in the elasticity of erythrocytes during short-term storage at 4°C. In turn, on the 28th day of erythrocyte storage, a significant decrease in the Elongation Index for shear stresses greater than 1 Pa was observed, which indicates the stiffening of the erythrocyte membrane structure, reducing their elasticity. The relative decrease in the Elongation Index of erythrocytes stored for 28 days compared to erythrocytes measured at the beginning was similar and slightly greater than 30% for shear stresses greater than 3 Pa. For shear stresses lower than 3 Pa, the relative change in elongation index was smaller than for shear stresses greater than 3 Pa and increased with the increase in shear stress. Conclusions: The elongation index of erythrocytes stored in the anticoagulant solution at 4°C, initially increases in the entire range of applied shear stresses in the first few days from the moment of blood collection and preparation at the Tissue Bank, and then decreases, but on the ninth day of storage the elongation index is still higher than for blood immediately after collection.

14

A dynamic spectrin-dimer self association regulates of red cell membrane mechanical stability

88%

Mohandas N. , An X. L. , Lecomte M. C. , Gratzer W.

Cellular and Molecular Biology Letters

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2001

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tom 06

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nr 2

15

Human red blood cell thiopurine methyl transferase: HPLC assay for phenotype determination

88%

Boulieu R. , Gallant I. , Sauviat M. , Dervieux T.

Cellular and Molecular Biology Letters

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1999

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tom 04

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nr 3

16

Cylindrical shapes of red blood cell microexovesicles

88%

Iglic A. , Kralj-Iglic V. , Peterlin P. , Hagerstrand H.

Cellular and Molecular Biology Letters

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1998

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tom 03

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nr 4

EN

Cylindrical microexovesicles were induced in human erythro-cytes by echinocytic amphiphile dodecyl maltoside. It is suggested that the effect of the curvature deviator is relevant for the stability of the observed cylindrical microexovesicle shapes.

17

Mechanical stress and hemin pretreatment effects on kinetic parameters of erythrocytes response to hyperosmotic shock

88%

Pantaler E. R. , Shpakova N. M.

Cellular and Molecular Biology Letters

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1998

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tom 03

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nr 2

18

Molecular studies of the erythrocyte spectrin tetramerization region

88%

Park S. , Mehboob S. , Luo B. H. , Hurtuk M. G. , Johnson M. E. , Fung L. W. M.

Cellular and Molecular Biology Letters

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2001

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tom 06

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nr 2

19

The influence of X-rays on human erythrocytes. Primary radicals

88%

Gonciarz M. , Szweda-Lewandowska Z.

Cellular and Molecular Biology Letters

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2002

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tom 07

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nr Suppl.

20

The role of the non-local bending energy in the red blood cell response to membrane deformations

88%

Kuzman D. , Gros M. , Vrhovec S. , Svetina S. , Zeks B.

Cellular and Molecular Biology Letters

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2001

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tom 06

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nr 2