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1.
Lucia Di Giambattista P. Grimaldi S. Gaudenzi D. Pozzi M. Grandi S. Morrone I. Silvestri A. Congiu Castellano 《European biophysics journal : EBJ》2010,39(6):929-934
We have made a preliminary analysis of the results about the effects on tumoral cell line (lymphoid T cell line Jurkat) induced
by UVB radiation (dose of 310 mJ/cm2) with and without a vegetable mixture. In the present study, we have used two techniques: Fourier transform infrared spectroscopy
(FTIR) and flow cytometry. FTIR spectroscopy has the potential to provide the identification of the vibrational modes of some
of the major compounds (lipid, proteins and nucleic acids) without being invasive in the biomaterials. The second technique
has allowed us to perform measurements of cytotoxicity and to assess the percentage of apoptosis. We already studied the induction
of apoptotic process in the same cell line by UVB radiation; in particular, we looked for correspondences and correlations
between FTIR spetroscopy and flow cytometry data finding three highly probable spectroscopic markers of apoptosis (Pozzi et
al. in Radiat Res 168:698–705, 2007). In the present work, the results have shown significant changes in the absorbance and
spectral pattern in the wavenumber protein and nucleic acids regions after the treatments. 相似文献
2.
The assembly of a large physical map of genomes requires simultaneous analysis of many cosmid clones for overlapping regions. The search for overlapping regions may be achieved by various means. High-performance liquid chromatography (HPLC) provides an alternative to gel electrophoresis since microgram amounts of each DNA fragment may be collected into individual test tubes for further analysis. HPLC has been used to identify overlapping cosmid clones from a pool of cosmid DNA containing the terminal portion of the long arm of the human X chromosome (Xq24-qter). Among 400 cosmids analyzed, 3 were shown to overlap. 相似文献
3.
Compression wood (CW) contains higher quantities of β-1-4-galactan than does normal wood (NW). However, the physiological
roles and ultrastructural distribution of β-1-4-galactan during CW formation are still not well understood. The present work
investigated deposition of β-1-4-galactan in differentiating tracheids of Cryptomeria japonica during CW formation using an immunological probe (LM5) combined with immunomicroscopy. Our immunolabeling studies clearly
showed that differences in the distribution of β-1-4-galactan between NW (and opposite wood, OW) and CW are initiated during
the formation of the S1 layer. At this stage, CW was strongly labeled in the S1 layer, whereas no label was observed in the S1 layer of NW and OW. Immunogold labeling showed that β-1-4-galactan in the S1 layer of CW tracheids significantly decreased during the formation of the S2 layer. Most β-1-4-galactan labeling was present in the outer S2 region in mature CW tracheids, and was absent in the inner S2 layer that contained helical cavities in the cell wall. In addition, delignified CW tracheids showed significantly more labeling
of β-1-4-galactan in the secondary cell wall, suggesting that lignin is likely to mask β-1-4-galactan epitopes. The study
clearly showed that β-1-4-galactan in CW was mainly deposited in the outer portion of the secondary cell wall, indicating
that its distribution may be spatially consistent with lignin distribution in CW tracheids of Cryptomeria japonica. 相似文献
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6.
Using a digital imaging fluorescence microscope, we have detected a rapid transient increase in the free cytosolic calcium concentration in a single rat basophilic leukemia cell (RBL-2H3) after antigen stimulation. Calcium ions were transported very rapidly (within 1 s) after a lag time (about 10 s at 37 degrees C) from the external environment into the cytoplasm. On the basis of the present experimental results we conclude that the gradual changes in the overall fluorescence intensity observed for a cell suspension are due to the distribution of different lag times shown by different cells as to the calcium influx through membrane calcium channels. 相似文献
7.
Lucia Lioi 《Biologia Plantarum》1987,29(1):49-53
Relationships among storage proteins in seeds from cultivars and primitive accessions of the four economically most important
species ofPhaseolus — P. vulgaris, P. coccineus, P. acutifolius andP. lunatus — were studied.
Analysis of SDS-polyacrylamide gel electrophoretic patterns of storage seed proteins revealed common characteristics in the
major groups of polypeptides forP. vulgaris, P. coccineus andP. acutifolius, while clear differences existed between thesePhaseolus species and P.lunatus. 相似文献
8.
Phorbol myristate acetate inhibits increases in membrane fluidity induced by anti-IgM in B cells 总被引:3,自引:0,他引:3
J Mizuguchi N Utsunomiya M Nakanishi Y Arata 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(8):2495-2499
Anti-IgM or anti-IgD stimulates B cells to induce increases in inositol phospholipid metabolism and intracellular free calcium concentration [( Ca2+]i). Anti-IgM also causes increases in membrane fluidity that occur more promptly than those in [Ca2+]i in resting B cells as well as BAL17 B lymphoma cells. However, other B cell activators such as LPS or PMA did not induce the membrane fluidity changes. Furthermore, sodium fluoride, which is considered to be an activator of the guanine nucleotide-binding protein, caused increases in membrane fluidity as well as increased [Ca2+]i or inositol phospholipid metabolism. Anti-IgM- or sodium fluoride-induced increases in membrane fluidity were inhibited by 20-min pretreatment of cells with PMA, but not by 24-h pretreatment. These results indicate that membrane fluidity changes are closely associated with increased [Ca2+]i after cross-linkage of membrane Ig and are regulated by protein kinase C in B cells. 相似文献
9.
Bruna Tedeschi Patrizia Vernole M.Lucia Sanna Benedetto Nicoletti 《Human genetics》1992,89(5):543-547
Summary Chromosome fragile sites are inducible by aphidicolin in cultured human lymphocytes. To assess the frequency and distribution of these common fragile sites in the general population, a cytogenetic survey was performed on 126 subjects, 59 males and 67 females, whose age ranged from 1 day to 72 years. Common fragile sites, induced by aphidicolin, were widespread and showed a remarkably different sensitivity among individuals; age influenced the overall frequency of fragile sites. Moreover, both age and sex seemed to modulate the expression of specific fragile sites. In our population, the most common fragile sites were: 3p14, 16q23, Xp22, 6q26, 1p31, 4q31, 1p22, 7q22, 2q33, 3q27, 2q31, 7q32, 14q24, 10q22, 5q31, 2q37, 6p21. 相似文献
10.
Carbohydrate structures of acetylcholine receptor from Torpedo californica and distribution of oligosaccharides among the subunits 总被引:8,自引:0,他引:8
H Nomoto N Takahashi Y Nagaki S Endo Y Arata K Hayashi 《European journal of biochemistry》1986,157(2):233-242
The structure of carbohydrates in acetylcholine receptor (AChR) from Torpedo californica is reported. Oligosaccharides released quantitatively from the whole molecule by N-oligosaccharide glycopeptidase digestion were fractionated by thin-layer chromatography and further purified by high-performance liquid chromatography. We show that more than 70% of the total oligosaccharide chains in Torpedo AChR are of the high-mannose type with the structures (Man)8(GlcNAc)2 and (Man)9(GlcNAc)2. The structure of these oligosaccharides were determined by proton nuclear magnetic resonance spectroscopy. These two types of oligosaccharides were shown to be distributed different proportions in all subunits of Torpedo AChR. We also show that several kinds of complex-type oligosaccharides comprising the rest of the carbohydrate in the protein exist mainly in the gamma and delta subunits. The structure of the carbohydrate moiety that is distributed on the four subunits of AChR was also examined by susceptibility to endo-beta-N-acetylglucosaminidase and sialidase and by binding affinity to lectins, e.g. concanavalin A, leucoagglutinating phytohemagglutinin, and wheat germ agglutinin. 相似文献