Vol.7 No.3 September 2002
| Volume 7 (2002) pp 839-843 | |
| Title | PLANAR, CYLINDRICAL AND SPHERICAL ELECTRICAL DOUBLE LAYERS IN BIOLOGICAL SYSTEMS. THE EFFECT OF COUNTERION SIZE |
| Authors | Klemen Bohinc1,Aleš Iglič1, Tomaž Slivnik1 and Veronika Kralj-Iglič 2 |
| Abstract | The effect of counterion size on the electrical properties of an electrolyte solution in contact with charged planar, cylindrical and spherical surfaces is considered. Electrostatic interaction is considered by means of the mean electrostatic field, while the finite size of particles constituting the electrolyte solution is considered via the excluded volume effect within the lattice statistics. Different sizes of counterion are described by different values of the lattice constant. It is shown that the excluded volume effect considerably decreases the calculated number density of counterions near the charged surface. This effect is more pronounced in cylindrical geometry than in spherical geometry, and less pronounced than in planar geometry. |
| Address and Contact Information | 1Faculty of Electrical Engineering, Tržaška 25, SI-1000 Ljubljana, Slovenia, 2Institute of Biophysics, Faculty of Medicine, Lipičeva 2, SI-1000 Ljubljana, Slovenia |
 ![[Rozmiar: 1332 bajtĂłw]](pic/abstract.gif){kind=small} |
|
| Volume 7 (2002) pp 845-848 | |
| Title | MOLECULAR MARKERS OF INBRED RADISH (Raphanus sativus var. Radicola Pers.) LINES |
| Authors | Tatiana V. Matveeva*, Anna V. Simonova and Ludmila A. Lutova |
| Abstract | An approach which could be used for quick searches for RAPD markers is described for groups of radish lines with certain morphological traits. The lines are characterized by various morpho-physiological abnormalities, including tumor formation (lines 12, 19, and 21) and non-terminal development of the flower meristem as a variant of tumor growth (line 6). We found four markers which differentiate tumor radish lines 12, 19, and 21 from the others, and two which differentiate line 6. |
| Address and Contact Information | St. Petersburg State University, 199034 St. Petersburg, Russia * Corresponding author, E-mail: radishlet@yahoo.com |
|
|
| Volume 7 (2002) pp 849-858 | |
| Title | ALTERNATIVE METHODS OF PLANT TRANSFORMATION - A SHORT REVIEW |
| Authors | Monika Rakoczy-Trojanowska* |
| Abstract | Several methods of transformation are currently available for delivering exogenous DNA to plant cells. Agrobacterium-mediated transformation, microprojectile bombardment and direct protoplast transformation are routinely used today. However, each of them has certain disadvantages, which led to research into the development of novel alternative systems such as infiltration, electroporation of cells and tissues, electrophoresis of embryos, microinjection, pollen-tube pathway, silicon carbide- and liposomemediated transformation. The low efficiency of transformation is considered to be the main reason for the limited popularity of the alternative transformation methods, other than infiltration and silicon carbide-mediated transformation, which seem to be the most promising ones for practice. |
| Address and Contact Information | Department of Plant Genetics, Breeding and Biotechnology, Agricultural
University, Nowoursynowska 166, 02-787 Warszawa, Poland * E-mail: RAKOCZY@ALPHA.SGGW.WAW.PL |
|
|
| Volume 7 (2002) pp 859-876 | |
| Title | In Vivo PHOSPHORYLATION OF Drosophila melanogaster NUCLEAR LAMINS DURING BOTH INTERPHASE AND MITOSIS |
| Authors | Ryszard Rzepecki1,2* and Paul A. Fisher1 |
| Abstract | To study phosphorylation of D. melanogaster nuclear lamins in vivo, we used Kc tissue culture cells. Kc cells contain products of both lamin genes, the lamin Dm0 gene encoding constitutive polypeptides expressed in almost all cell types and the developmentally regulated lamin C gene. We grew K c cells in low phosphate medium and labelled them with [32P]H3PO4. To obtain mitotic cells we used vinblastine to arrest cells in metaphase. Cells were collected, washed, lysed and resultant extracts fractionated in the presence of protein phosphatase inhibitors. D. melanogaster proteins were then denatured by boiling in SDS plus DTT, followed by immunoaffinity chromatography and SDS-PAGE purification. As anticipated, we found that a CNBr fragment derived from the Nterminal part of lamin Dm0-derivatives (amino acid residues 2-158; fragment A) was phosphorylated during both interphase and mitosis. Interphase but not mitotic phosphorylation was found on an internal CNBr fragment (derived from the end of the central rod domain and the first part of the C-terminal lamin tail; amino acid residues 385-548; fragment D). Interphase only phosphorylation was also detected on another CNBr fragment derived from the extreme C-terminal portion of lamin Dm0-derivatives (amino acid residues 549-622; fragment E). To supplement these data, we used 2-D tryptic peptide mapping followed by phosphorImager analysis. We routinely detected at least seven 'spots' derived from interphase lamins but only a single mitotic lamin phosphopeptide. |
| Address and Contact Information | 1The Department of Pharmacological Sciences, University Medical Center, The
State University of New York at Stony Brook, Stony Brook, NY 11794-8651,
USA, 2Institute of Biochemistry and Molecular Biology, University of Wrocław, Przybyszewskiego Street 63/77, 51-148 Wrocław, Poland * Corresponding author, E-mail: rzepecki@ibmb.uni.wroc.pl, tel. (04871) 375 63 08 |
|
|
| Volume 7 (2002) pp 877-883 | |
| Title | METHYLATION OF THE ARGININE-GLYCINE-RICH REGION IN THE FRAGILE X MENTAL RETARDATION PROTEIN FMRP DIFFERENTIALLY AFFECTS RNA BINDING |
| Authors | Robert B. Denman |
| Abstract | The C-terminal end of the fragile X mental retardation protein contains a stretch of amino acid residues that are enriched in arginine and glycine. Recent studies using recombinant FMRPs have demonstrated that this region participates in RNA binding in vitro, with calculated Kds ranging from 1- 10 nM depending on the RNA. It is known that other arginine-glycine-rich proteins are subject to site-specific methylation by protein arginine methyltransferases (PRMTs) that are particularly abundant in most cells. We have demonstrated that the interaction of homoribopolymer mimetic RNAs with human FMRP (hFMRP) made in PRMT-containing cell-free lysates is more sensitive to increasing salt concentrations than recombinant hFMRP expressed in bacteria. We have also shown that blocking methylation with adenosine-2', 3'- dialdehyde (AdOx) alters homoribopolymer binding and hFMRP target mRNA binding; both increases and decreases are observed as a function of methylation. These data suggest that changes in PRMT activity that occur during development, or arise via signal transduction may be a means of regulating the binding of hFMRP to mRNA in vivo. |
| Address and Contact Information | New York State Institute for Basic Research, Department of Molecular Biology, Laboratory of Biochemical Molecular Neurobiology, 1050 Forest Hill Road Staten Island, NY 10314 |
|
|
| Volume 7 (2002) pp 885-888 | |
| Title | EVIDENCE FOR THE HYDROLYSIS OF TOPICAL APPLIED LIPOSOMAL LIPIDS IN HUMAN STRATUM CORNEUM |
| Authors | Sebastian Zellmer |
| Abstract | Liposomes were incubated with an extract of human plantar stratum corneum. The liposomal lipids were hydrolysed, if composed of soy-bean phosphatidylcholine or phosphatidylglycerol. Rigid lipids were not degraded. The temperature optimum of the hydrolysis was between 30-35°C. CaCl2 enhanced, while EDTA reduced the rate of hydrolysis, indicating that the hydrolysis is due to a phospholipase A2. |
| Address and Contact Information | Labsoft Diagnostics AG, Robert-Franz-Ring 21, 06108 Halle, Germany * E-mail: zellmer@labsoft.de |
|
|
| Volume 7 (2002) pp 889-894 | |
| Title | USE OF THE POST-INSERTION METHOD FOR THE FORMATION OF LIGAND-COUPLED LIPOSOMES |
| Authors | Theresa M. Allen, Puja Sapra and Elaine Moase |
| Abstract | A new technique is described for the formation of ligand-targeted liposomes that can be used with whole antibodies, antibody fragments, peptides or other ligands. The ligands are coupled to polyethylene glycol micelles and then transferred in a simple incubation step from the micelles into the outer monolayer of pre-formed, drug-loaded liposomes. This versatile method allows a combinatorial approach to the design of targeted liposomes that minimises manufacturing complexities, allowing a variety of ligands to be inserted into a variety of pre-formed liposomes containing a variety of drugs. This allows the ligand-targeted therapeutics to be tailored to the needs of individual patients. |
| Address and Contact Information | Department of Pharmacology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7 |
|
|
| Volume 7 (2002) pp 895-903 | |
| Title | THE ROLE OF LIPID PHASE STRUCTURE IN THE INTERACTION OF LACTATE DEHYDROGENASE WITH PHOSPHATIDYLSERINE. ACTIVITY STUDIES |
| Authors | Grzegorz Terlecki1*, Elżbieta Czapińska1 and Jan Gutowicz2** |
| Abstract | Lactate dehydrogenase is one of the enzymes of the glycolytic path. It has been shown to be able to bind in vitro to cellular membranes. The presence of anionic phospholipids induces changes in the catalytic properties of the enzyme similar to those found when the enzyme is bound to natural membranes. In this study, a nonionic detergent (Tween 20), at concentrations not affecting the catalytic activity of LDH, was used to study the role of the lipid supramolecular structure in the interaction between pig skeletal muscle lactate dehydrogenase and phosphatidylserine. Tween 20 changes the equilibrium of concentrations between the lipid supra-molecular forms. The detergent at the used concentration values did not alter the activity of the enzyme when it was used on its own, but did diminish the level of inhibition induced by the studied phospholipid. The obtained results showed that the interaction is reversible and that the bilayer structure of the lipid is essential for the inhibition. |
| Address and Contact Information | 1Department of Medical Biochemistry, Wrocław Medical University, Wrocław,
Poland, 2Department of Physico-Chemistry of Microorganisms, Institute of Microbiology, University of Wrocław, Wrocław, Poland *E-mail: terlecki@biochem.am.wroc.pl **Corresponding author, E-mail: gutowicz@microb.uni.wroc.pl |
|
|
| Volume 7 (2002) pp 905-910 | |
| Title | FURTHER EVIDENCE FOR THE IMPORTANCE OF LIPID BILAYERS IN THE INTERACTION BETWEEN LACTATE DEHYDROGENASE AND PHOSPHATIDYLSERINE |
| Authors | Grzegorz Terlecki1* and Jan Gutowicz2** |
| Abstract | Lactate dehydrogenase (LDH) is one of the glycolytic enzymes, which have been proved to have the capability to reverse non-specific adsorption on cellular membranous structures in vitro, as well as on the structural proteins of the contractile system of muscle cells. It has been suggested that this binding may play a physiological role, as it alters the enzyme's kinetic properties. Our previous studies on this enzyme showed that its interaction with some anionic phospholipids reveals similar characteristics and similar effect on the activity of the enzyme to those wich had been observed for the interaction with membranous structures. Disruption of the lipid bilayers by nonionic detergent (Tween 20) restored the enzyme activity inhibited by the presence of phosphatidylserine (PS) liposomes. In this study, we used the measurement of enzyme tryptophanyl fluorescence spectra to monitor the interaction and possible changes in the enzyme conformation. The investigation provided further evidence of the importance of the bilayer structure in this interaction. Similarly to the effect on the activity of the enzyme, the addition of Tween 20 diminishes the quenching of the LDH tryptophanyl fluorescence, and finally completely restores the fluorescence. |
| Address and Contact Information | 1Department of Medical Biochemistry, Wrocław Medical University, Wrocław,
Poland, 2Department of Physico-Chemistry of Microorganisms, Institute of Microbiology, University of Wrocław, Wrocław, Poland *E-mail: terlecki@biochem.am.wroc.pl **Corresponding author, E-mail: gutowicz@microb.uni.wroc.pl |
|
|
| Volume 7 (2002) pp 911-917 | |
| Title | PHYSICAL MAPPING OF rDNA IN DENDRANTHEMA NANKINGENSE AND ITS CLOSE RELATED SPECIES BY FLUORESCENT IN SITU HYBRIDIZATION |
| Authors | Wenkui Wang1*, Silan Dai1 and Maoxue Li2 |
| Abstract | Distribution of 18S-26S rDNA on the chromosomes of Dendranthema nankingense and its two close-related species D. nankingense and D. lavendulifolium was studied by fluorescent in situ hybridization with a JHD 2- 15A DNA clone. Six rDNA loci were found in D. nankingense, eight in D. lavendulifolium, and twelve in D. indicum. The rDNA loci number and pattern were applied to analyze the phylogenetic relationship of the three closely related species |
| Address and Contact Information | 1College of Landscape Architecture, Beijing Forestry University, Beijing
100083, P.R. China, 2College of Life Sciences, Peking University, Beijing 100871, P.R. China * Corresponding author |
|
|
| Volume 7 (2002) pp 919-922 | |
| Title | LIPID-BASED ANTIFUNGAL AGENTS: A CONCISE OVERVIEW |
| Authors | Sevtap Arikan |
| Abstract | The development of lipid formulations of antifungal drugs has been a remarkable progress in the systemic antifungal arena. The lipid-based amphotericin B formulations; amphotericin B lipid complex (ABLC), amphotericin B colloidal dispersion (ABCD), and liposomal amphotericin B (LAMB) have been in clinical use since the 1990s. They are significantly less nephrotoxic than the parent compound and can be safely used at higher doses. The primary cost of these formulations is significantly high and the extent of data related to their head-to-head comparison remains limited. The lipid formulation of nystatin, liposomal nystatin, is another lipid-based polyene under development. Available data concerning the in vitro activity, pharmacokinetic profile, in vivo efficacy, and safety of these formulations are summarized in this overview. |
| Address and Contact Information | Hacettepe University Medical School, Department of Microbiology and Clinical Microbiology, Mycology Laboratory, 06100 Ankara, Turkey |
|
|
| Volume 7 (2002) pp 923-927 | |
| Title | CONSTRUCTION OF STABLE ANIONIC LIPOSOME-PLASMID PARTICLES USING THE HEATING METHOD: A PRELIMINARY INVESTIGATIONs |
| Authors | M. Reza Mozafari1, Celia J. Reed2, Christopher Rostron1, Cengiz Kocum3 and Erhan Piskin3 |
| Abstract | Recent advances in liposome technology have resulted in the production of effective drug delivery formulations, although toxicity concerns remain. In order to overcome this problem we prepared anionic liposomes without using any volatile organic solvent or detergent. Liposomes prepared by this heating method (HM-liposomes) were characterised in terms of morphology, stability and DNA incorporation efficiency. Scanning tunnelling microscopy (STM) and optical microscopy were used to study the morphological characteristics and size distribution of HM-liposomes. Microscopic studies revealed formation of spherical bilayered structures with stabilities of at least eight months and also enabled measuring the diameter and the bilayer thickness of the vesicles. Plasmid DNA encapsulation efficiencies of up to 70.3% were determined for HM-liposomes. |
| Address and Contact Information | 1School of Pharmacy and Chemistry, 2School of Biomolecular Sciences, Liverpool John Moores University, Liverpool, L3 3AF, England, UK. 3Hacettepe University, Chemical Engineering Department, Beytepe (06532), Ankara, Turkey * Corresponding author, E-mail: pacmmoza@livjm.ac.uk |
|
|
| Volume 7 (2002) pp 929-935 | |
| Title | ANTIOXIDATIVE ACTIVITY OF SOME PHENOXY AND ORGANOPHOSPHOROUS COMPOUNDS |
| Authors | Dorota Bonarska, Halina Kleszczyńska and Janusz Sarapuk |
| Abstract | Experiments were performed in order to check whether biological activity of some organophosphorous compounds widely applied as herbicides: 2,4-dichlorophenoxyacetic acid (1) and its sodium salt (2), Nphosphonomethylglycine acid (3) and its sodium salt (4), diethyl 1-butylamino- 1-cyclohexanephosphonate (5) and diethyl 9-butylamino-9-fluorenephosphonate (6) followed from their oxidative activity. The compounds studied differed in their polarity and hydrophobicity. On the contrary, it was found that all herbicides protected erythrocyte membranes against partial peroxidation induced by UV irradiation. The effect was somewhat differentiated and followed the sequence: 5 > 1 > 2 > 6 > 3 > 4. The observed differences between the antioxidative activities of the compounds are probably related to differences in their ability to incorporate into the lipid phase of the erythrocyte membrane. Once incorporated, they change fluidity of the membranes. The extent of the changes was determined in fluorescence measurements. Polarization and anisotropy coefficients of erythrocyte membranes modified by micromolar concentrations of herbicides at different temperatures were measured for that purpose. Generally, they followed the sequence found for antioxidative activity of the herbicides studied, which confirms the assumption of close correlation between the depth of incorporation of a herbicide into the erythrocyte membrane and its protective efficiency. |
| Address and Contact Information | Department of Physics and Biophysics, Agricultural University, Norwida 25, 50-375 Wrocław, Poland |
|
|
W. MEJBAUM-KATZENELLENBOGEN'S MOLECULAR BIOLOGY SEMINARS
9. LIPOSOMES. FROM MODELS TO APPLICATIONS
MAY 26-29, 2002; WROCłAW/SZKLARSKA PORĘBA/PIECHOWICE, POLAND
Late Abstracts
| Volume 7 (2002) pp 938 | |
| Late Abstract> | |
| Abstracts List |
INFLUENCE OF PIPERIDINE CHLORIDES DERIVATIVES ON THERMOTROPIC BEHAVIOUR OF PHOSPHATIDYLCHOLINE AND PHOSPHATIDYLCHOLINE/ CHOLESTEROL BILAYERS Bożenna Różycka-Roszak, Edyta Woźniak and Zofia Dega-Szafran - p938 |
VIII POLISH CONFERENCE ON CELL BIOLOGY
MAY 26-29, 2002; WROCłAW/SZKLARSKA PORĘBA/PIECHOWICE, POLAND
Supplement - Erratum and Late Abstracts
| Volume 7 (2002) pp 940 | |
| Erratum and Late Abstracts | |
| Abstracts List |
ERRATUM - p940 RATE CONSTANTS OF THE REACTION OF HYDROXYL RADICALS (°OH) WITH ALCOHOL DEHYDROGENASE (ADH) AND GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE (GAPDH) Aleksandra Kowalczyk, Aneta Dudek and Mieczysław Puchała - p941ELECTROPHYSIOLOGICAL STUDY ON THE MECHANISM OF MODULATION OF GABAERGIC SYNAPTIC CURRENTS BY HYDROGEN IONS Maria Mandat, Ewa D. Żarnowska, Katarzyna Mercik and. Jerzy W. Mozrzymas - p942INTEGRITY OF SPERMATOZOA AND THEIR MITOCHONDRIAL ENERGETIC STATUS IN RELATION TO MOTILITY OF SPERMATOZOA Małgorzata Piasecka, Jerzy Kawiak, Zbigniew Szych, Maria Laszczyńska, Alicja Kozanecka and Blanka Kołodziej - p943CHARACTERISATION OF INTEGRIN CONTENT IN HUMAN NORMAL AORTIC VALVES AND IN VALVES AFFECTED BY CALCIFIC AORTIC STENOSIS Małgorzata Przybyło, Ewa Stępień, Roman Pfitzner, Anna Lityńska and Jerzy Sadowski - p944 |