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1.
Szkanderová S Vávrová J Hernychová L Neubauerová V Lenco J Stulík J 《Radiation research》2005,163(3):307-315
Analyses of the protein expression profiles of irradiated cells may be beneficial for identification of new biomolecules of radiation-induced cell damage. Therefore, in this study we exploited the proteomic approach to identify proteins whose expression is significantly altered in gamma-irradiated human T-lymphocyte leukemia cells. MOLT-4 cells were irradiated with 7.5 Gy and the cell lysates were collected at different times after irradiation (2, 5 and 12 h). The proteins were separated by two-dimensional electrophoresis and quantified using an image evaluation system. Proteins exhibiting significant radiation-induced alterations in abundance were identified by peptide mass fingerprinting. We identified 14 proteins that were either up- or down-regulated. Cellular levels of four of the proteins (Rho GDP dissociation inhibitor 1 and 2, Ran binding protein 1, serine/threonine protein kinase PAK2) were further analyzed by two-dimensional immunoblotting to confirm the data obtained from proteome analysis. All identified proteins were classified according to their cellular function, including their participation in biochemical and signaling pathways. Taken together, our results suggest the feasibility of the proteome method for monitoring of cellular radiation responses. 相似文献
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Tykva R Hlavácek J Vlasáková V Cerný B Borovicková L Bennettová B Holík J Slaninová J 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,848(2):258-263
Reversed-phase high-performance liquid radio-chromatography (radio-HPLC) was set up to detect the time course of labeled degradation product formation of the pentapeptide H-Tyr-Asp-Pro-Ala-Pro-OH (5P), which has oostatic effects in different insect species. The detection limit of the system was in the range of 80-150 Bq. To follow formation of the degradation products, three amino acid residues in 5P were independently tritiated: Tyr1, Pro3 and Pro5. Each of the three tritiated peptides was analyzed after incubation with fresh hemolymph or ovaries of Neobellieria bullata. In the incubation mixture, free terminal amino acids and shortened sequences of 5P were identified. A metabolite of tyrosine represented the only exception; it was finally identified as water using degradation of [3H]Tyr by tyrosinase. Metabolic degradation of [3H]Tyr-5P was found to be considerably quicker than that of H-[3H]Tyr-Asp-Pro-Ala-OH (4P). The degradation of 5P was considerably slower in ovaries in comparison to hemolymph. 相似文献
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Ahmed EA van der Vaart A Barten A Kal HB Chen J Lou Z Minter-Dykhouse K Bartkova J Bartek J de Boer P de Rooij DG 《DNA Repair》2007,6(9):1243-1254
In male germ cells the repair of DNA double strand breaks (DSBs) differs from that described for somatic cell lines. Irradiation induced immunofluorescent foci (IRIF's) signifying a double strand DNA breaks, were followed in spermatogenic cells up to 16 h after the insult. Foci were characterised for Mdc1, 53BP1 and Rad51 that always were expressed in conjecture with gamma-H2AX. Subsequent spermatogenic cell types were found to have different repair proteins. In early germ cells up to the start of meiotic prophase, i.e. in spermatogonia and preleptotene spermatocytes, 53BP1 and Rad51 are available but no Mdc1 is expressed in these cells before and after irradiation. The latter might explain the radiosensitivity of spermatogonia. Spermatocytes from shortly after premeiotic S-phase till pachytene in epithelial stage IV/V express Mdc1 and Rad51 but no 53BP1 which has no role in recombination involved repair during the early meiotic prophase. Mdc1 is required during this period as in Mdc1 deficient mice all spermatocytes enter apoptosis in epithelial stage IV when they should start mid-pachytene phase of the meiotic prophase. From stage IV mid pachytene spermatocytes to round spermatids, Mdc1 and 53BP1 are expressed while Rad51 is no longer expressed in the haploid round spermatids. Quantifying foci numbers of gamma-H2AX, Mdc1 and 53BP1 at various time points after irradiation revealed a 70% reduction after 16 h in pachytene and diplotene spermatocytes and round spermatids. Although the DSB repair efficiency is higher then in spermatogonia where only a 40% reduction was found, it still does not compare to somatic cell lines where a 70% reduction occurs in 2 h. Taken together, DNA DSBs repair proteins differ for the various types of spermatogenic cells, no germ cell type possessing the complete set. This likely leads to a compromised efficiency relative to somatic cell lines. From the evolutionary point of view it may be an advantage when germ cells die from DNA damage rather than risk the acquisition of transmittable errors made during the repair process. 相似文献
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Utíkal P Köcher M Koutná J Bachleda P Drác P Cerná M Buriánková E 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2004,148(2):183-187
The authors describe their indication tactics for AAA elective treatment. Based on one-month morbidity and mortality they evaluate the results obtained in the past six years and compare the methods of open surgery, endovascular repair and combined strategy in AAAs elective repair. 相似文献
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Adámková H Vicar J Palasová J Ulrichová J Simánek V 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2004,148(1):103-105
A double-blind, placebo-controlled clinical trial was performed to investigate the effectiveness of a herbal-based dentifrice in the control of gingivitis. Forty volunteers completed the 84-day study. All subjects were balanced for parameters measured - plaque index (PI), community periodontal index of treatment needs (CPITN) and papillary bleeding index (PBI). The dentifrice was effective in reducing symptoms of gingivitis as evaluated by the CPITN and PBI indexes. 相似文献
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Chlamydomonas reinhardtii arg7-8 (arg2) mutant strains carrying a hitherto undescribed mutation in their argininosuccinate lyase gene (ARG7) that leads to arginine auxotrophy have been used together with the corresponding wild-type gene as a very reliable transformation system since 1989. In this study, we finally identify the molecular nature of the arg7-8 mutation as a (6073)G to A transition in exon 9 of ARG7 leading to a (288)Gly to Ser exchange near the active site of the protein. The same mutation was found in the ARG7 genes of three commonly used C. reinhardtii laboratory strains, namely cw15-302 arg2, CC-48, and CC-1618. We did not observe exact spontaneous reversion of the arg7-8 allele in our study, but did identify two different and rare intragenic suppressor mutations, (27)Leu to Phe and (285)Tyr to Phe. In our hands, only transformation of the arg7-8 strain with a truncated nonfunctional wild-type ARG7 gene lacking 124 codons at its 5' end led to exact reversion of the mutant base (6073)A to the wild-type (6073)G, presumably by recombination. This system offers a positive selection scheme for homologous recombination (HR) and may, therefore, be useful to the methodical improvement of recombination in Chlamydomonas. 相似文献
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Skalnikova H Martinkova J Hrabakova R Halada P Dziechciarkova M Hajduch M Gadher SJ Hammar A Enetoft D Ekefjard A Forsstrom-Olsson O Kovarova H 《Journal of proteome research》2011,10(2):404-415
Resistance to anti-cancer drugs is a well recognized problem and very often it is responsible for failure of the cancer treatment. In this study, the proteome alterations associated with the development of acquired resistance to cyclin-depedent kinases inhibitor bohemine, a promising anti-cancer drug, were analyzed with the primary aim of identifying potential targets of resistance within the cell that could pave a way to selective elimination of specific resistant cell types. A model of parental susceptible CEM T-lymphoblastic leukemia cells and its resistant counterpart CEM-BOH was used and advanced 2-D liquid chromatography was applied to fractionate cellular proteins. Differentially expressed identified proteins were further verified using immunoblotting and immunohistochemistry. Our study has revealed that Rho GDP-dissociation inhibitor 2, Y-box binding protein 1, and the HSP70/90 organizing protein have a critical role to play in resistance to cyclin-depedent kinases inhibitor. The results indicated not only that quantitative protein changes play an important role in drug-resistance, but also that there are various other parameters such as truncation, post-translational modification(s), and subcellular localization of selected proteins. Furthermore, these proteins were validated for their roles in drug resistance using different cell lines resistant to diverse representatives of anti-cancer drugs such as vincristine and daunorubicin. 相似文献
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The use of water lettuce (Pistia stratiotes L.) for rhizofiltration of a highly polluted solution by cadmium and lead 总被引:1,自引:0,他引:1
The effectiveness of heavy metal uptake from contaminated nutrient solution by four aquatic macrophytes (Pistia stratiotes L., Salvinia auriculata AubL, Salvinia minima Baker, and Azolla filiculoides Lam) was estimated in this study. The influence of cadmium (3.5 mg L(-1) and 10.5 mg L(-1)) and lead (25 mg L(-1) and 125 mg L(-1)) on the stress symptoms was observed through the determination of chlorophyll content and transpiration rate over 14 days of the experiment. The results of the present study showed extreme reductions in Cd and Pb concentrations in solution during the first 4 days. The accumulation of Pb in plant tissues was the highest during the first 4 days and was more than 10 times higher in the roots (42,862 mg kg(-1)) than in the leaves (3867 mg kg(-1)). The accumulation of Cd slowly increased and was the highest at the end of the experiment. Concentrations in roots (3923 mg kg(-1)) were roughly 6 times higher than in the leaves (624 mg kg(-1)). Results showed significant decrease in the transpiration rate at Pb treatment and a significant increase at Cd treatment during 48 hours of exposition. 相似文献