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1

Lipid and protein composition of exovesicles released from human erythrocytes following treatment with amphiphiles

100%
Hagerstrand H., Isomaa B.
Biophysics of Membrane Transport
|
1994
|
tom 12
|
nr 2
2

Lipid composition and lectin-mediated agglutination of Candida kefyr cells grown in media enriched with choline or its analogues

86%
Sharma S. C., Singh B.
Acta Biochimica Polonica
|
1989
|
tom 36
|
nr 3-4
3

Fatty acid profile of meat of seasonally fed slow-growing rabbits

86%
Rasinska E., Czarniecka-Skubina E., Rutkowska J., Przybylski W., Brzozowski M.
Animal Science Papers and Reports
|
2017
|
tom 35
|
nr 3
The study aimed at determining fatty acid (FA) profiles of meat of seasonally fed slow-growing rabbits in relation to lipid composition of feeds and their intake. In each season, 21 weaned male rabbits (Popielno White breed) were assigned into two homogenous groups: the control (C, n=7) and seasonally fed - summer (S, n=14) or winter (W, n=14). Meat lipid, MUFA and PUFA contents were significantly higher in the S and C groups, most likely due to a higher lipid intake, while S-rabbits had two-fold higher n-3 PUFA contents than C-rabbits. This resulted in a better thrombogenic index in S- rather than in C-rabbits, similarly as it was the case for the hypocholesterolemic/ hypercholesterolemic (H/H) ratio. In relation to the other groups myristic and palmitic acid contents in meat were greater in W-rabbits due to a higher SFA intake. As compared with the C diet, seasonal diets were associated with a higher proportion of n-3 PUFA in meat. This resulted in an improvement of the n-6/n-3 ratio (3.62 on average) in meat from seasonally fed rabbits. Both seasonal diets also increased the content of odd-numbered and branched-chain acids (OBCFA; twofold greater than in the C group). S-rabbits had greater daily body mass gains and were heavier than the W-rabbits. The content of palmitooleic acid (C16:1 n-7) in meat was high irrespective of the diet. Feeding strategies associated with outdoor rearing, adopted in small farms, favour local rabbit populations. Thus, it is recommended to promote native, slow-growing rabbit breeds, a source of valuable nutrients.
4

Alzheimer's disease: its origin at the membrane, evidence and questions

86%
Buchet R., Pikula S.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 3
Numerous results on membrane lipid composition from different regions of autopsied Alzheimer's disease brains in comparison with corresponding fractions isolated from control brains revealed significant differences in serine- and ethanolamine-containing glycerophospholipid as well as in glycosphingolipid content. Changes in membrane lipid composition are frequently accompanied by alterations in membrane fluidity, hydrophobic mismatch, lipid signaling pathways, transient formation and disappearance of lipid microdomains, changes in membrane permeability to cations and variations of other membrane properties. In this review we focus on possible implications of altered membrane composition on b-amyloid precursor protein (APP) and on proteolysis of APP leading eventually to the formation of neurotoxic b-amyloid (Ab) peptides, the major proteinaceous component of extracellular senile plaques, directly involved in Alzheimer's disease pathogenesis.
5

Lipids composition of plasma membranes from root of corn seedlings under salt stress and synthetic compounds treatment

72%
Konturska O. O., Palladina T. A.
Acta Physiologiae Plantarum
|
2007
|
tom 29
|
nr 1 Suppl.
6
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Effect of bull feeding intensity in the finishing period on slaughter traits and lipid compositions of meat

72%
Bilik K., Choroszy Z., Lopuszanska-Rusek M.
Polish Journal of Food and Nutrition Sciences
|
2007
|
tom 57
|
nr 4[A]
31-35
A total of 12 Limousin bull calves were assigned to two feeding groups (6 animals per group) analogous in terms of body weight. Bulls were reared during calfhood with suckler cows and then fed indoors with farm-produced feeds (silages, hay, concentrates) to obtain a body weight gain of approximately 1000 g/day. The basic bulky feed was maize silage (fed ad libitum), supplemented with meadow hay (1 kg/day), and different amounts (according to group) of concentrate (kg/100 kg body weight): 1.0 (group KK-I) or 0.6 (KK-P). The study showed that compared to semi-intensive feeding, intensive feeding of Limousin bulls in the finishing period with diets containing maize silage, meadow hay and concentrate had a more favourable effect on fattening traits, slaughter traits, economic efficiency of feeding and fatty acid profile in the intramuscular fat, n-6/n-3 PUFA ratio and total cholesterol content of the longissimus muscle.
7

Transmembrane segment M2 of glycine receptor as a model system for the pore-forming structure of ion channels

72%
Bednarczyk P., Szewczyk A., Dolowy K.
Acta Biochimica Polonica
|
2002
|
tom 49
|
nr 4
The glycine receptor belongs to the ligand-gated ion channel superfamily. It is a chlo­ride conducting channel composed of four transmembrane domains. It was previously shown that the second transmembrane domain (M2) of the glycine receptor forms an ion conduction pathway throught lipid bilayers. The amino-acid sequence of the transmembrane segment M2 of the glycine receptor has a high homology to all recep­tors of the ligand-gated ion channel superfamily. In our report, we have used a syn­thetic M2 peptide. It was incorporated into a planar membrane of known lipid compo­sition and currents induced by M2 were measured by the Black Lipid Membrane tech­nique. When the planar lipid bilayer was composed of 75% phosphatidylethanolamine and 25% phosphatidylserine, the reversal potential measured in a 150/600 mM KCl (cis/trans) gradient was -19 mV suggesting that the examined pore was preferential to anions, Pk/Pci = 0.25. In contrast, when 75% phosphatidylserine and 25% phosphatidylethanolamine was used, the reversal potential was +20 mV and the pore was preferential to cations, Pk/Pci = 4.36. Single-channel currents were recorded with two predominant amplitudes corresponding to the main-conductance and sub-conductance states. Both conductance states (about 12 pS and 30 pS) were mea­sured in a symmetric solution of 50 mM KCl. The observed single-channel properties suggest that the selectivity and conductance of the pore formed by the M2 peptide of the glycine receptor depend on the lipid composition of the planar bilayer.
8

Construction and optimisation of a computer model for a bacterial membrane

72%
Murzyn K., Pasenkiewicz-Gierula M.
Acta Biochimica Polonica
|
1999
|
tom 46
|
nr 3
The main steps in the construction of a computer model for a bacterial membrane are described. The membrane has been built of 72 lipid molecules, 54 of which being 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatidylethanolamine (POPE) and 18 - 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphatidyl-rac-glycerol (POPG) molecules (thus in the proportion of 3:1). The membrane was hydrated with 1955 water molecules (approximately 27 water molecules per lipid). To neutralise the electronic charge (-e) on each POPG molecule, 18 sodium ions (Na+) were added to the membrane close to the POPG phosphate groups. The atomic charges on the POPE and POPG headgroups were obtained from ab initio quantum mechanical restrained electrostatic potential fitting (RESP) (Bayly et al., 1993, J. Phys. Chem. 97, 10269) using the GAMESS program at the 6-31G* level (Schmidt et al., 1993, J. Comput. Chem. 14, 1347). The model constructed in this way provided an initial structure for subsequent molecular dynamics simulation studies intended to elucidate the atomic level interactions responsible for the structure and dynamics of the bacterial membrane.
9

Liposomal drug delivery, a novel approach: PLARosomes

72%
Kozubek A., Gubernator J., Przeworska E., Stasiuk M.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 3
Almost from the time of their rediscovery in the 60's and the demonstration of their entrapment potential, liposomal vesicles have drawn attention of researchers as potential carriers of various bioactive molecules that could be used for therapeutic applications in humans and animals. Several commercial liposome-based drugs have already been discovered, registered and introduced with great success on the pharmaceutical market. However, further studies, focusing on the elaboration of more efficient and stable amphiphile-based vesicular (or non-viral) drug carriers are still under investigation. In this review we present the achievements of our group in this field. We have discovered that natural amphiphilic dihydroxyphenols and their semisynthetic derivatives are promising additives to liposomal lipid compositions. The presence of these compounds in lipid composition enhances liposomal drug encapsulation, reduces the amount of the lipid carrier necessary for efficient entrapment of anthracycline drugs by a factor of two, stabilizes liposomal formulation of the drug (both in suspension and in a lyophilized powder), does not influence liposomal fate in the blood circulation system and benefits from other biological activities of their resorcinolic lipid modifiers.
10

Sphingomyelin-cholesterol liposomes. Effect of natural resorcinolic amphiphiles on their properties

72%
Przeworska E., Kamps J. A. A. M., Scherphof G. L., Kozubek A.
Cellular and Molecular Biology Letters
|
1999
|
tom 04
|
nr 2
11

Changes in the composition of membrane lipids in relation to induction and differentiation of callus tissue of two rape [Brassica napus] varieties

72%
Zur I., Skoczowski A., Niemczyk E.
Folia Histochemica et Cytobiologica. Supplement
|
1997
|
tom 35
|
nr 2
12

Influence of DnaK and DnaJ chaperones on Escherichia coli membrane lipid composition

72%
Sienczyk J., Sklodowska A., Grudniak A., Wolska K. I.
Polish Journal of Microbiology
|
2004
|
tom 53
|
nr 2
The content of fatty acids extracted from the membranes of E. coli MC1061 harboring the wild-type dnaKdnaJ alleles and its AdnaJ and AdnaKdnaJ derivatives was compared. It was demonstrated that dodecanoic acid was missing in NPLs fraction extracted from both mutants grown at 42°C. Phospholipids extracted from mutant strains were deprived of hexadecanoic acid methyl ester and octadecanol, the latter being correlated with the presence of octadecanoic acid. The amount of LPS extracted from AdnaKdanJ mutant was significantly lower when compared with wild-type strain and AdnaJ mutant.
13

Correlation between bean seed surface lipids and Acanthoscelides obtectus Say development

58%
Nietupski M., Szafranek B., Ciepielewska D., Synak E., Fornal L., Szafranek J.
Journal of Plant Protection Research
|
2005
|
tom 45
|
nr 2
125-133
The influence of bean seed surface lipids on infestation of seeds by Acanthoscelides obtectus Say was investigated. The experiments were performed in dual-choice bioassays on three bean varieties: Blanka, Bor and Longina. The collected data for natural and solvent washed seeds concerned the number of ovipositions, embryo mortality, lack of seed-boring activity, dead larvae inside seeds and developed insects. The results clearly indicated that bean seed surface lipids are involved in all infestation stages, and could be used to distinguish resistant and non-resistant varieties of been. Chemical analyses revealed the following groups of surface lipids: wax esters, long chain primary alcohols, n-alkanes, sterols, fatty acids, squalene, aldehydes, monoacylglycerols, ketones and fatty acid esters. Quantitative composition of surface lipids was analysed using selected chemometric procedures to determine correlation with bioactivity. Cluster analysis of surface lipid composition enabled to distinguish resistant and non-resistant varieties. Fatty acids and monoacylglycerols were found to deter bean weevil infestation, while alkan-1-ols acted as attractants
14

Decrease in beech [Fagus sylvatica] seed viability caused by temperature and humidity conditions as related to membrane damage and lipid composition

58%
Ratajczak E., Pukacka S.
Acta Physiologiae Plantarum
|
2005
|
tom 27
|
nr 1
The aim of this study was to determine if the loss of germinability and viability of beech (Fagus sylvatica L.) seeds stored at different variants of temperature (4, 20, and 30 °C) and relative humidity (RH: 45 and 75 %) is associated with a loss of membrane integrity and changes in lipid composition. Beech seeds stored for 9 weeks gradually lost viability at a rate dependent on temperature and humidity. The harmful effect of temperature increased with growing humidity. The loss of seed viability was strongly correlated with an increase in membrane permeability and with production of lipid hydroxyperoxides (LHPO), which was regarded as an indicator of peroxidation of unsaturated fatty acids. The condition of membranes was assessed on the basis of their permeability and the state of lipid components: phospholipids and fatty acids. During seed storage we obterved a decline in concentration of individual phospholipids and fatty acids, proportional to the loss of seeds viability. We also detected a decrease in concentrations of α-tocopherol and sterols, which play an important role in protection of membranes against the harmful influence of the environment. Our results show that the germinability of beech seeds declines rapidly at temperature above 0 °C and growing humidity. This is due mainly to the loss ofmembrane integrity, caused by peroxidation of unsaturated fatty acids.
15

Increased activity of phospholipase C in aortas of spontaneously hypertensive rats correlates with decreased sphingomyelin: total phospholipid ratio

58%
Gryckiewicz E., Dettlaff A., Pawelczyk T.
Cellular and Molecular Biology Letters
|
1998
|
tom 03
|
nr 1
The activity of phospholipase C (PLC) in the aortas of spontaneously hypertensive rats (SHR) was higher than in the aortas of age-matched normotensive Wistar-Kyoto rats (WKY). This was associated with the higher level of inositol 1,4,5-trisphosphate and diacylglycerol in aortas of SHR compared to the level of these compounds found in aortas of WKY. Observed changes in PLC activity correlates with changes in phospholipid composition of SHR aortas. The sphingomyelin (SM) to total phospholipid ratio decreased significantly in aortas of SHR compared to WKY. Since, SM was proposed to be the major PLC δ inhibitor in vivo (Arch. Biochem. Biophys. 297 (1992) 328-333) it might be possible that observed higher activity of PLC in aortas of SHR results from decreased content of this phospholipid.
16

Is a fluid-mosaic model of biological membranes fully relevant? Studies on lipid organization in model and biological membranes

58%
Wisniewska A., Draus J., Subczynski W. K.
Cellular and Molecular Biology Letters
|
2003
|
tom 08
|
nr 1
The basic concept of the fluid-mosaic model of Singer and Nicolson, an essential point of which is that the membrane proteins are floating in a sea of excess lipid molecules organized in the lipid bilayer, may be misleading in understanding the movement of membrane components in biological membranes that show distinct domain structure. It seems that the lipid bilayer is an active factor in forming the membrane structure, and the lipid composition is responsible for the presence of domains in the membrane. The main role in the process of domain formation is played by cholesterol and sphingolipids. The results presented here show that in a binary mixture of cholesterol and unsaturated phospholipids, cholesterol is segregated out from the bulk unsaturated liquid-crystalline phase. This forms cholesterol-enriched domains or clustered cholesterol domains due to the lateral nonconformability between the rigid planar ring structure of cholesterol and the rigid bend of the unsaturated alkyl chain at double bond position. These cholesterol-enriched domains may be stabilized by the presence of saturated alkyl chains of sphingomyelin or glycosphingolipids, and also by specific proteins which selectively locate in these domains and stabilize them as a result of protein-protein interaction. Such lipid domains are called “rafts” and have been shown to be responsible both for signal transduction to and from the cell and for protein sorting. We also looked at whether polar carotenoids, compounds showing some similarities to cholesterol and affecting membrane properties in a similar way, would also promote domain formation and locate preferentially in one of the lipid phases. Our preliminary data show that in the presence of cholesterol, lutein (a polar carotenoid) may segregate out from saturated lipid regions (liquid-ordered phase) and accumulate in the regions rich in unsaturated phospholipids forming carotenoid-rich domains there. Conventional and pulse EPR (electron paramagnetic resonance) spin labeling techniques were employed to assess the molecular organization and dynamics of the raft-constituent molecules and of the raft itself in the membrane.
17

Biotechnological strategies to alter lipid and vitamin composition in chloroplasts of higher plants

58%
Kanwischer M., Dormann P.
Biological Letters
|
2005
|
tom 42
|
nr 2 Spec.Vol.
18

Antioxidant enzymes and membrane lipid composition of disease resistant tomato plants regenerated from crown galls

44%
Barna B., Pogany M.
Acta Physiologiae Plantarum
|
2001
|
tom 23
|
nr 3
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