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排序方式: 共有1147条查询结果,搜索用时 21 毫秒
1.
Alba Vecchini Luciano Binaglia Paolo Di Nardo Marilena Minieri Giuseppe Tallarida 《Molecular and cellular biochemistry》1992,110(1):47-54
The activity of phospholipid base exchange enzymes has been evaluated in cardiac sarcolemmal membranes from Syrian Golden
hamsters and from a hamster strain (UM-X7.1) characterized by a genetic form of hypertrophic cardiomyopathy. No choline base
exchange activity and only a little serine base exchange activity were detected, whereas the ethanolamine base exchange enzyme
was found highly active in membranes from both strains. For this reason, the present study is focussed on the ethanolamine
base exchange enzyme. The apparent Km for ethanolamine of ethanolamine base exchange enzyme from Syrian Golden membranes and
from UM-X7.1 strain membranes are 18 and 32 μM, respectively. The specific activity of the sarcolemmal ethanolamine base exchange
enzyme is lower in the UM-X7.1 strain than in Syrian Golden hamsters. The calcium-dependence of the enzyme appears different
when the membranes from the two strains are compared. Indeed, after removal of the membrane-bound divalent cations, comparable
activities are found in both membrane preparations, whereas, upon addition of Ca2+ to the incubation mixtures, the activity of the enzyme is enhanced in the membranes from Syrian Golden strain more than in
those from UM-X7.1 strain. The cholesterol content of sarcolemmal membranes is higher in the cardiomyopathic strain than in
the Syrian Golden hamsters. A possible relation between changes of the membrane lipid composition and of the ethanolamine
base exchange activity is discussed. 相似文献
2.
Tiziana Bellini Diana Degani Maurizio Matteuzzi Franco Dallocchio 《Bioscience reports》1990,10(1):73-78
Pre-treatment of human lymphocytes with 17-estradiol diminishes the increase in concentration of cytosolic free calcium after stimulation with phytohaemagglutinin. The effect is dependent on 17-estradiol concentration and on the preincubation time. The effect is not due to an interaction between 17-estradiol and phytohaemagglutinin, but appears to be a consequence of the binding of the hormone to the cell surface. The effect is specific for 17-estradiol, since the isomer and other steroid hormones (progesterone, testosterone, diethylstilbestrol and 5-androstan), have no effect. Since the effect of the 17-estradiol can be suppressed by treatment of lymphocytes with ouabain, it appears that the effect of estradiol on the rise of cytosolic calcium induced by phytohaemagglutinin is mediated by the (Na, K)-ATPase. 相似文献
3.
Silvia Sartoris Andrea De Lerma Barbaro Tiziana Cestari Giuseppe Tridente Roberto S. Accolla 《Immunogenetics》1994,39(1):8-14
RJ 2.2.5 is a human B cell mutant, derived from Raji cells, which has lost expression of major histocompatibility complex (MHC) class II genes because of a defect in the AIR1 locus function. The MHC class II-positive phenotype can be restored by introducing an active AIR1 locus or its mouse equivalent, Air-1. An example of the latter is the H4 cell hybrid, derived by somatic cell fusion between RJ 2.2.5 and mouse class II-positive spleen cells. H4 contains a single mouse chromosome, autosome 16, in which the Air-1 locus maps, and an entire RJ 2.2.5-derived genome. In the present study we show that the physiologic target of the Air-1 locus product is contained within a limited HLA-DRA promoter sequence of 300 base pairs, encompassing the crucial Y, X, and W cis-acting elements. A plasmid construct, pDRA300neo, containing the HLA-DRA promoter sequence which drives the expression of the neomycin resistance gene, has been stably integrated in the genome of the H4 hybrid. Transfectants selected in the presence of G418 retain mouse chromosome 16 and express the DR genes. On the other hand, transfectants grown in a non-selective medium segregate mouse chromosome 16; this is accompanied by a loss of DRA gene expression and G418 resistance, although pDRA300neo is still integrated in the genome. These results offer scope for using this experimental model to clone the Air-1 gene in a straightforward way.
Correspondence to: R. S. Accolla. 相似文献
4.
5.
M Stefanini S Giliani T Nardo S Marinoni V Nazzaro R Rizzo G Trevisan 《Mutation research》1992,273(2):119-125
Trichothiodystrophy (TTD) is a rare autosomal recessive disorder characterized by brittle hair, mental and growth retardation, peculiar face, ichthyosis, and in 20% of the reported cases photosensitivity. Cellular photosensitivity due to the same genetic defect present in xeroderma pigmentosum group D (XP-D) has been described in several patients. Nine patients with clinical symptoms diagnostic for TTD have been identified in Italy to date. We report the results of DNA repair investigations performed in cultured fibroblasts from these patients and 8 TTD parents. Survival, DNA repair synthesis and RNA synthesis following UV irradiation were all normal in the 8 TTD heterozygous cell strains. Among the 9 TTD-affected individuals, normal cellular UV sensitivity was observed in the 2 patients without signs of clinical photosensitivity. In contrast, the other 7 TTD cell strains showed a notable reduction in UV-induced DNA repair synthesis (UDS) levels, ranging between 40% and 5-15% of normal values. Complementation analysis indicated that in the repair-deficient TTD cell strains the genetic defect is the same as that present in XP-D cells. The biochemical heterogeneity of the XP-D defect in TTD patients characterized by different degrees of defective UDS results in different patterns of response to the killing effect of UV light in non-proliferating cells. 相似文献
6.
Felicia Carotenuto Laura Teodori Anna Maria Maccari Luciano Delbono Giuseppe Orlando Paolo Di Nardo 《Journal of cellular and molecular medicine》2020,24(5):2704-2716
Regenerative therapies including stem cell treatments hold promise to allow curing patients affected by severe cardiac muscle diseases. However, the clinical efficacy of stem cell therapy remains elusive, so far. The two key roadblocks that still need to be overcome are the poor cell engraftment into the injured myocardium and the limited knowledge of the ideal mixture of bioactive factors to be locally delivered for restoring heart function. Thus, therapeutic strategies for cardiac repair are directed to increase the retention and functional integration of transplanted cells in the damaged myocardium or to enhance the endogenous repair mechanisms through cell-free therapies. In this context, biomaterial-based technologies and tissue engineering approaches have the potential to dramatically impact cardiac translational medicine. This review intends to offer some consideration on the cell-based and cell-free cardiac therapies, their limitations and the possible future developments. 相似文献
7.
Amino Acids - Unfortunately in the online published article, the name of compound “L-salicylidenealanine” was published with incorrect spelling in the section “Synthesis of... 相似文献
8.
Pedrotta Tiziana Gobet Erika Schwörer Christoph Beffa Giorgia Butz Christoph Henne Paul D. Morales-Molino César Pasta Salvatore van Leeuwen Jacqueline F. N. Vogel Hendrik Zwimpfer Elias Anselmetti Flavio S. Grosjean Martin Tinner Willy 《Vegetation History and Archaeobotany》2021,30(6):789-813
Vegetation History and Archaeobotany - Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record... 相似文献
9.
Fadhlaoui-Zid Karima Cossu Piero Sanna Daria Scarpa Fabio Lai Tiziana Castelli Alberto Casu Marco Maltagliati Ferruccio 《Hydrobiologia》2021,848(18):4225-4240
Hydrobiologia - Recent research hypothesised that the Siculo-Tunisian Strait might fit, at least for some species, the picture of a genetic transitional zone instead of a sharp genetic break... 相似文献
10.
Tiziana Genovese Emanuela Mazzon Emanuela Esposito Rosanna Di Paola Kanneganti Murthy Lewis Neville 《Free radical research》2013,47(7):631-645
The aim of the present study was to assess the effect of a metalloporphyrinic peroxynitrite decomposition catalyst, ww-85, in the pathophysiology of spinal cord injury (SCI) in mice. Spinal cord trauma was induced by the application of vascular clips to the dura via a four-level T5–T8 laminectomy. SCI in mice resulted in severe trauma characterized by oedema, neutrophil infiltration, production of inflammatory mediators, tissue damage and apoptosis. ww-85 treatment (30–300 µg/kg, i.p. 1 h after the SCI) significantly reduced in a dose-dependent manner: (1) the degree of spinal cord inflammation and tissue injury, (2) neutrophil infiltration (myeloperoxidase activity), (3) nitrotyrosine formation and PARP activation, (4) pro-inflammatory cytokines expression, (5) NF-κB activation and (6) apoptosis. Moreover, ww-85 significantly ameliorated the recovery of limb function (evaluated by motor recovery score) in a dose-dependent manner. The results demonstrate that ww-85 treatment reduces the development of inflammation and tissue injury associated with spinal cord trauma. 相似文献