Volume 48 (2002) No. 3
Metabolic Characterization of Insulin Resistance Syndrome Feature Loci in Three Brown Norway-Derived Congenic Strains
O. ŠEDA1,2, L. ŠEDOVÁ1, L. KAZDOVÁ2, D. KŘENOVÁ1, V. KŘEN1,3........................81
1Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic
2Institute for Clinical and Experimental Medicine, Prague, Czech Republic
3Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Corresponding author: Vladimír Křen, Institute of Biology and Medical Genetics, 1st Medical Faculty,
Charles University, Prague, Albertov 4, 12800 Prague 2, Czech Republic. Tel.: +420 (2) 2496 8147; email: vkren(zavináč)lf1.cuni.cz.
Abstract.
Full text pp. 81-82 83-84 85-86 87-88
Modulatory Effects of Long-Chain n-3 Fatty Acids on Cell Functions
M. A. PUERTOLLANO, M. A. de PABLO, G. ÁLVAREZ de CIENFUEGOS.....................89
University of Jaén, Faculty of Experimental Sciences, Department of Health Sciences,
Unit of Microbiology, Jaén, Spain
Corresponding author: Manuel Antonio de Pablo Martínez, University of Jaén,
Faculty of Experimental Sciences, Department of Health Sciences, Unit of Microbiology,
E-23071-Jaén, Spain. Tel.: +34 953 012 003; fax: +34 953 012 141, e-mail: mapablo@ujaen.es.
Abstract.
Full text pp. 89-91 92-93 94-95
Characterization of Functional Domains of Human Interferon Gamma by Specific Monoclonal Antibodies
G. NACHEVA1, M. BOYANOVA1, K. TODOROVA1, S. KYURKCHIEV2 , I. IVANOV1......96
1Institute of Molecular Biology, Bulgarian Academy of Sciences, Sofia, Bulgaria
2Institute of Biology and Immunology of Reproduction, Bulgarian Academy of Sciences, Sofia, Bulgaria
Corresponding author: Ivan G. Ivanov, Institute of Molecular Biology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 21, 1113 Sofia, Bulgaria. Tel./ Fax: +359 (2) 73 62 27; e-mail: iviv@obzor.bio21.bas.bg.
Abstract.
Full text pp. 96-97 98-99 100-101
Chromosome Aberrations in Peripheral Blood Lymphocytes in Subjects Occupationally Exposed to Ionizing Radiation or Chemical Clastogens
H. LALIĆ1, B. RADOŠEVIĆ-STAŠIĆ2................................102
1Department of Occupational and Environmental Medicine, 2Department of Physiology and Immunology, Medical Faculty, University of Rijeka, Rijeka, Croatia
Corresponding author: Hrvoje Lalić, Department of Occupational and Environmental Medicine, Medical Faculty, University of Rijeka, 51000 Rijeka, Brentinijeva 5, Croatia. Tel.: +385 (51) 371094, 098 (328110); fax: +385 (51) 675699; e-mail: biserr@medri.hr.
Abstract.
Full text pp. 102-103 104-105 106-107
Renewal of the Culture Medium Induces a Temporary Decrease in the Gap Junctional Communication Accompanied by Degradation and Re-establishment of Gap Junctions in the V79-4 Chinese Hamster Cell Line
J. VÍTEK, E. OBOŘILOVÁ, P. MAZURA, M. BENEŠOVÁ.....................108
Research Institute of Child Health, Department of Cell Biology, Brno, Czech Republic
Corresponding author: Jiří A. Vítek, Rolnická 7, 625 00 Brno, Czech Republic.
Abstract.
Full text pp. 108-109 110-111 112-113
Short Communications
Tumour-Inhibitory Effects of Dendritic Cells Administered at the Site of HPV 16-Induced Neoplasms
L. MENDOZA1, J. BUBENÍK1, J. ŠÍMOVÁ1, J. KORB1, J. BIEBLOVÁ1, V. VONKA2, M. INDROVÁ1, R. MIKYŠKOVÁ1, T. JANDLOVÁ1..........................................114
1Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague
2Institute of Haematology and Blood Transfusion, Prague, Czech Republic
Corresponding author: Luis Mendoza, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 37 Praha 6, Czech Republic. Tel.: +420 (2) 20183461; Fax: +420 (2) 24310955.
Abstract.
Full text pp. 114-115 116-117 118-119
A Rat Linkage Map Based on BC x LEW Intercross
A. C. M. BONNÉ, M. G. C. W. den BIEMAN, G. F. GILLISSEN, L. F. M. van ZUTPHEN,
H. A. van LITH.................................120
Department of Laboratory Animal Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
Corresponding author: Anita Bonné, Department of Laboratory Animal Science, Faculty of Veterinary Science, Utrecht University, P.O. Box 80166, 3508 TD Utrecht, The Netherlands.
Tel.: +31 (30) 2533959; Fax: +31 (30) 2537997; e-mail: Bonne@las.vet.uu.nl.
Abstract.
Full text pp. 120-121 122-123
Metabolic Characterization of Insulin Resistance Syndrome Feature Loci in Three Brown Norway-Derived Congenic Strains
O. ŠEDA, L. ŠEDOVÁ, L. KAZDOVÁ, D. KŘENOVÁ, V. KŘEN
Studies on genetic determination of the insulin resistance syndrome in rat models revealed several susceptibility loci for features of this complex phenotype, i.e. dyslipidemia, insulin resistance and obesity. We analysed the influence of introgression of the RNO4, RNO20 segments of SHR origin and RNO8 segment of PD/Cub origin (all previously shown to be involved in (dys)regulation of carbohydrate and lipid metabolism) onto the genetic background of a common progenitor, the Brown Norway (BN/Cub) rat. The differential segments were genetically characterized in the BN.PD-D8Rat39/D8Rat35 (BN-Lx, RNO8 congenic), BN.SHR-Il6/Cd36 (BN.SHR4, RNO4 congenic) and BN.PD-D8Rat39/D8Rat3, SHR-D4Mgh2/Cd36, SHR-D20Wox3/D20Mgh5 (BN-Lx 1K, RNO4, 8, 20 triple congenic) strains and their metabolic profiling was performed. After one week of high-sucrose diet, all congenic strains showed substantially higher levels of serum triglycerides and free fatty acids as well as impaired glucose tolerance in comparison with the BN/Cub progenitor strain. The BN-Lx 1K triple congenic strain displayed the most profound dyslipidemia, glucose intolerance and highest increase of triglyceridemia in response to high-sucrose diet overall, though accompanied with the significantly lowest adiposity index. These results further support the role of genes present within the studied chromosomal regions in observed metabolic disturbances. Furthermore, these findings point to the studied loci within the gene-gene and gene-environment interactions involved in pathogenesis of the insulin resistance syndrome. The set of defined congenic strains provides a possibility of assessing individual features of such a complex phenotype.
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M. A. PUERTOLLANO, M. A. de PABLO, G. ÁLVAREZ de CIENFUEGOS
In recent years, it has been demonstrated that certain fatty acids are involved in the modulation of immune system functions. The mechanisms responsible for these effects are not fully elucidated, but many hypotheses have described numerous changes in the cell functionality as the main factors capable of altering the immune functions. In the present investigation, we have analysed the potential effects of FFA on cell viability, production of superoxide radicals or proteasome activity in assays in vitro. Thus, different FFA, such as OA, EPA or SA have been incorporated to cellular cultures at a concentration of 100 microM. Phospholipase, cyclooxygenase or lipooxygenase inhibitors abolished the loss of thymocyte viability exerted by EPA, the most immunosuppressive fatty acid. Similarly, measurement of the oxidative process by NBT reduction in cells treated with EPA was markedly increased. Nevertheless, the proteasome activity as a mechanism that participates in T-cell activation was not modified by direct action of the different fatty acids on the in vitro cultures. Overall, these results underline the differential role of several fatty acids (particularly long-chain n-3 polyunsaturated fatty acids) in order to modulate many functions of the immune system.
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G. NACHEVA, M. BOYANOVA, K. TODOROVA, S. KYURKCHIEV, I. IVANOV
For the study of functional domains of hIFNgamma, two MABs were characterized. Both MABs, named 1E11 and 5D6, were sequence-specific for hIFNgamma. According to the estimated additivity index, they recognized epitopes located at distinct non-overlapping areas of the hIFNgamma molecule. When pre-incubated with hIFNgamma, MAB 1E11 was able to neutralize the antiviral as well as the antiproliferative activity of the cytokine. This indicated that MAB 1E11 was specific either for the domain responsible for binding to the cell receptor or for a domain required for both functions. By contrast, the second MAB 5D6 did not interfere with any of the two hIFNgamma biological activities. The epitope of MAB 5D6 was located between the amino acid residues Leu 135 and Glu 143 by using different forms of C-terminally truncated hIFNgamma. These data allow the conclusion that the last nine C-terminal amino acids are not essential for the receptor binding and biological functioning of this cytokine. The possible role of hIFNgamma C-terminus in the intracellular cascade of events is discussed.
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H. LALIĆ, B. RADOŠEVIĆ-STAŠIĆ
To get an insight into genotoxic risk in some occupations, in this study the chromosome aberration analysis of peripheral blood lymphocytes was made in 20 physicians and nurses exposed to a low dose of ionizing radiation in a hospital, 12 individuals working with X-rays in a cement factory and 19 technicians working with some chemical toxic agents in the laboratories of a medical school. The control group consisted of 14 sex- and age-matched unexposed persons living in the same district area. The data showed that the total number of chromosome aberrations on 200 scored metaphases in all examined groups were almost the same and inside the low-permitted values. In hospital workers, however, the percentage of acentric and dicentric fragments (1.63 ± 0.28 vs 0.31 ± 0.21 and 0.47 ± 0.18 vs 0.0, respectively) increased predominantly in contrast to cement-factory employees and laboratory workers, where a higher incidence of minutes (0.58 ± 0.19 vs 0.31 ± 0.2) or gaps (2.21 ± 0.37 vs 1.15 ± 1.15) was noticed. Moreover, in groups exposed to low doses of ionizing radiation (hospital and factory), a positive correlation was found between the total number of chromosome aberrations and the 6-year absorption dose or working period, suggesting an effect of cumulative dosage.
The data emphasize that the continuous chromosomal aberration analysis should be obligatory for individuals exposed to various genotoxic substances, even in occupational conditions where according to dosimetric analysis they are exposed to permitted levels of radiation.
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J. VÍTEK, E. OBOŘILOVÁ, P. MAZURA, M. BENEŠOVÁ
To replace the culture medium with a fresh one is a routine action of the mammalian cell culture technique. It is generally assumed that this act per se does not cause any significant physiological response of a cell population that would significantly interfere with the experimental procedures in culture. However, in this series of experiments we demonstrate that the exchange of the culture medium for a fresh one may induce a significant temporary decrease in the GJIC, assessed by the dye coupling method in the V79-4 Chinese hamster cell line. This effect is accompanied by a degradation of gap junctions and their re-establishment assessed by the semiquantitative immunocytochemistry of connexin43. The minimum value of GJIC was reached 45 min after the exchange of the medium. Afterwards, GJIC grew up again, reaching the standard value 3 or 4 h later. This effect does not just result from the exchange of medium as a mechanical action, is not caused by the change of pH and is of quantitative character. The fresh medium loses its capability to reduce GJIC after 3 h of conditioning with the same cells. We found that the value of the early inhibition of GJIC observed during the first 2 h of treatment with the inhibitor of GJIC-EG (applied together with a fresh culture medium) - was indistinguishable from the effect of the exchange of medium itself. Only after that point of time is the EG-induced inhibition of GJIC definitely distinguishable. The results demonstrate that a simple exchange of the culture medium, which is generally implemented in various experiments in culture, may cause serious physiological, biochemical and even morphological responses of cells and thus affect the final results of experiments in culture, especially regarding the early effects of drugs. Consequently, to avoid an undesirable response of the cell population reported in this paper we recommend to apply or remove drugs using a medium conditioned with the same cells for at least 3 h.
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Tumour-Inhibitory Effects of Dendritic Cells Administered at the Site of HPV 16-Induced Neoplasms
L. MENDOZA, J. BUBENÍK, J. ŠÍMOVÁ, J. KORB, J. BIEBLOVÁ, V. VONKA, M. INDROVÁ, R. MIKYŠKOVÁ, T. JANDLOVÁ
Experiments were designed to examine whether administration of APC at the site of HPV 16-associated tumours can inhibit tumour growth and whether the efficacy of established dendritic cell lines is comparable to that of fresh BMDC populations. Mice were inoculated s.c. with APC, either bone marrow-derived dendritic cells differentiated in medium supplemented with GM-CSF and IL-4 (BMDC), or with established dendritic cell lines DC2.4 or JAWS II. The pretreated mice, together with untreated controls, were challenged with syngeneic HPV 16-transformed cells MK16 at the site of APC administration. It has been found that both BMDC and dendritic cell lines can inhibit tumour growth and that the efficacy of the established dendritic cell lines DC2.4 and JAWS II was comparable to that of fresh BMDC populations. In vitro induction of proliferative spleen cell responses by co-cultivation with MK16 antigen-pulsed BMDC or MK16 antigen-pulsed dendritic cell lines revealed that both types of APC populations can prime immune reactions directed against syngeneic HPV 16-associated neoplasms. Taken together, the results suggest that local increase in the number of dendritic cells at the site of HPV 16-associated tumours can inhibit progression of the tumours and that the dendritic cell lines which are efficient in this respect can be considered and should be tested in both, preclinical and human systems for delivery of therapeutic vaccines against HPV 16-associated neoplasms.
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A. C. M. BONNÉ, M. G. C. W. den BIEMAN, G. F. GILLISSEN, L. F. M. van ZUTPHEN,
H. A. van LITH
Abstract. A genetic linkage map consisting of 258 polymorphic loci has been constructed on the basis of an F2 intercross between the BC/CpbU and LEW/OlaHsd inbred rat strains. When compared to previously published maps a discrepancy was found for rat chromosome 7. The map spans a sex averaged genetic length of 1790 cM and has an average marker spacing of 7.7 cM. It was estimated that this genetic map is linked to about 90% of the DNA in the rat genome. Because LEW/OlaHsd and BC/CpbU strains differ for dietary cholesterol susceptibility and hepatic copper content, the map is considered to be a valuable tool for studying the genetic background of these complex traits.
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