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61.
Alberto M. Martelli Lucia Manzoli Silvia Rubbini Anna Maria Billi Renato Bareggi Lucio Cocco 《Biology of the cell / under the auspices of the European Cell Biology Organization》1995,83(1):15-22
Summary— Using two-dimensional polyacrylamide gels stained with Coomassie blue we have studied the protein composition of the nuclear matrix obtained from mouse erythroleukemic nuclei kept at O°C throughout the isolation procedure to prepare the high ionic strength resistant fraction (control matrix) or stabilized in vitro or in vivo by different procedures prior to subfractionation (ie 37°C incubation of isolated nuclei; sodium tetrathionate exposure of purified nuclei; heat shock of intact cells). When the matrix obtained from 37°C incubated nuclei was compared with the control matrix, striking differences in the polypeptide pattern were seen if the protein was obtained in both cases from an equivalent number of nuclei. On the other hand, if the same amount of protein for both the samples was applied to the gels the differences were less evident. Sodium tetrathionate stabilization of isolated nuclei and heat shock of intact cells produced a matrix protein pattern that was very similar and differed from that of the in vitro heat-exposed matrix. Using specific polyclonal antisera, we demonstrate that nucleolar proteins B23/numatrin and C23/nucleolin were very abundant in the matrix obtained from chemically-treated nuclei or in vivo heat-stabilized nuclei but were recovered in very small amounts (B23) or completely absent (C23) in the matrix prepared from nuclei heated to 37°C in vitro. Differences were seen also in the recovery of nuclear lamins, and especially lamin B, that was poorly represented in the sodium tetrathionate-stabilized matrix. The results demonstrate that in mouse erythroleukemia cells the increased recovery of nuclear matrix protein that is seen after in vitro heating of isolated nuclei is predominantly due to an additional recovery of the same types of polypeptides that are detected also in the absence of such a treatment. The data also indicate that in vivo heat shock of intact cells produces a nuclear matrix protein pattern that is more similar to the pattern seen after stabilization of purified nuclei with sodium tetrathionate and differs significantly from that obtained by exposing nuclei to 37°C in vitro, unlike to that what previous reports have indicated. 相似文献
62.
Benthic algal mats and phytoplankton of Lake Gondwana (Northern Victoria Land, Antarctica) were investigated. Biomass, chlorophyll content and floristic analyses were carried out on algal mats. The mats are composed of two layers different in colour, floristic composition and chlorophyll content. The algal flora of the mats amount to 34 taxa (19 Cyanophyta, 7 Bacillariophyta, 8 Chlorophyta). The phytoplankton community is species-poor (only 5 taxa). Crytophyta account for about 98% of total algal density. 相似文献
63.
64.
Androgen Ablation Leads to an Upregulation and Intranuclear Accumulation of Deoxyribonuclease I in Rat Prostate Epithelial Cells Paralleling Their Apoptotic Elimination 总被引:1,自引:0,他引:1 下载免费PDF全文
65.
Characterization of Nine Novel Mutations in the CD40 Ligand Gene in Patients with X-Linked Hyper IgM Syndrome of Various Ancestry 总被引:3,自引:0,他引:3 下载免费PDF全文
Paolo Macchi Anna Villa Dario Strina Maria Grazia Sacco Federica Morali Duilio Brugnoni Silvia Giliani Elide Mantuano Anders Fasth Bengt Andersson Ben J. M. Zegers Giovanni Cavagni Igor Reznick Jacov Levy Israel Zan-Bar Yael Porat Paolo Air Alessandro Plebani Paolo Vezzoni Luigi D. Notarangelo 《American journal of human genetics》1995,56(4):898-906
X-linked immunodeficiency with hyper-IgM (HIGMX-1) is a rare disorder caused by defective expression of the CD40 ligand (CD40L) by activated T lymphocytes, resulting in inefficient T-B cell cooperation and failure of B cells to undergo immunoglobulin isotype switch. In the present work, we describe nine patients of various ancestry who bear different mutations in the X chromosome–specific CD40L gene. Two of the mutations were nonsense mutations, one each resulting in premature stop codons at amino acid residues 39 and 140. Three patients had single point missense mutations, one each at codons 126, 140, and 144. Another patient had a 4-bp genomic deletion in exon 2, resulting in a frameshift and premature termination. Three patients showed insertions, one each of 1, 2, and 4 nt, probably because of polymerase slippage, resulting in frameshift mutation and premature termination. Overall, these observations confirm the heterogeneity of mutations in HIGMX-1. However, the identification of two patients whose mutation involves codon 140 (previously shown to be altered in two other unrelated subjects) suggests that this may be a hotspot of mutation in HIGMX-1. In two additional patients with clinical and immunological features indistinguishable from canonical HIGMX-1, no mutation was detected in the coding sequence, in the 5' flanking region, or in the 3' UTR. 相似文献
66.
Silvia Köchling Johan T. den Dunnen Bernd Dworniczak Jürgen Horst 《Human genetics》1995,95(4):475-477
Duchenne muscular dystrophy (DMD) is one of the most common and severe X-linked disorders with an incidence of approximately 1 in 3500 newborn males. In more than 60% of DMD patients, deletions of part or all of the dystrophin gene have been shown. Despite this, carrier detection still poses a problem in some cases, because of the enormous size of the gene and the lack of sufficient numbers of informative markers. Here, we report the isolation and characterization of two additional microsatellite markers (IVS44SK12 and IVS44SK21) in intron 44 of the dystrophin gene. Both markers are useful for carrier detection either by indirect DNA analysis or by direct proof of loss of heterozygosity. 相似文献
67.
A new insoluble polymer containing a Cinchona alkaloid derivative has been synthesized and used as chiral ligand in the heterogeneous enantioselective dihydroxylation of olefins. It is shown that the enantioselectivity of the optically active diols obtained from both aliphatic and aromatic substrates is always comparable to that observed in the homogeneous phase under the same reaction conditions. A method for evaluating the enantiomeric excesses of the optically active products is also described. © 1995 Wiley-Liss, Inc. 相似文献
68.
Abstract The effects of doxycycline (DOX) and streptomycin (SM) treatment of Brucella melitensis infected mice on humoral immune response were examined. In female BALB/c mice, DOX was administered at a dose of 50 mg/kg/12 h, for 21 or 45 consecutive days, alone or combined with SM (10 mg/kg/12 h) for 14 days. All treatments induced a significant increase in specific IgG levels (ELISA and CIEP) against LPS and cytosolic antigens of Brucella during treatment. This was not related with therapeutic failure or relapse since all treatments induced a significant reduction in the degree of infection. 相似文献
69.
70.
Silvia M.C. Dias João B. Fernandes José G.S. Maia Otto R. Gottlieb Hugo E. Gottlieb 《Phytochemistry》1982,21(7):1737-1740
The trunk wood of an Amazonian Aniba (Lauraceae) species contains, besides dillapiol and the benzodioxane-type neolignan eusiderin, four bicyclo(3.2.1)octanoid neolignans. These comprise representatives of the canellin-type: the known methoxycanellin-A and the novel compounds characterized as (1R, 3S, 4S, 5S, 6S, 7R)-1-allyl-4-hydroxy-3, 5-dimethoxy-7-methyl-6-(3′-methoxy-4′, 5′-methylenedioxyphenyl)-8-oxo-bicyclo(3.2.1)octane; (1R, 3S, 4S, 5S, 6S, 7R)-1-allyl-4-hydroxy-3, 5-dimethoxy-7-methyl-6-(3′, 4′, 5′-trimethoxyphenyl)-8-oxobicyclo(3.2.1)octane and (1R, 4R, 5R, 6S, 7R, 8S)-1-allyl-4, 8-dihydroxy-5-methoxy-7-methyl-6-(3′-methoxy-4′,5′-methylenedioxyphenyl)-3-oxobicyclo(3.2.1)octane. 相似文献