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排序方式: 共有118条查询结果,搜索用时 15 毫秒
1.
Melanoma growth stimulatory activity (MGSA) was originally described as an endogenous growth factor for human melanoma cells. To test the hypothesis that an MGSA autocrine loop is responsible for the partial freedom from growth control observed in nevocytes and melanoma cells, MGSA growth response and MGSA mRNA/protein levels were examined in these cells compared with normal melanocytes. As a single agent, or in combination with other factors, MGSA stimulated the growth of normal human epidermal melanocytes as well as other growth promoters for melanocytes. Nevocytes were not as responsive to exogenous MGSA as melanocytes. MGSA mRNA was minimal or not detected in cultured normal melanocytes, although the protein was present when the cells were cultured in the presence of serum/growth factors and absent when serum/growth factors were omitted. In contrast, MGSA mRNA was constitutively expressed in the absence of exogenous growth factors in cultures established from benign intradermal and dysplastic nevi and melanoma lesions in different stages of tumor progression. Nevus cultures contained immunoreactive MGSA protein in the presence of serum but were negative or only faintly positive in the absence of serum. Melanoma cell lines were positive for MGSA protein in both the presence and the absence of serum. Thus, continued expression of both MGSA mRNA and MGSA protein in the absence of exogenous hormones or serum factors may correlate with partial freedom from growth control exhibited by malignant melanocytes. 相似文献
2.
Growth factor modulation of melanoma growth stimulatory activity mRNA expression in human malignant melanoma cells correlates with cell growth 总被引:2,自引:0,他引:2
This report demonstrates that the expression of melanoma growth stimulatory activity (MGSA) mRNA can be modulated in a positive fashion in the Hs294T human melanoma cell line by PDGF and MGSA. There is close correlation between MGSA expression and the pattern of cell growth in Hs294T cells. 相似文献
3.
Maria Antonietta Zoroddu Michelina Fruianu Roberto Dallocchio Andreina Masia 《Biometals》1996,9(1):91-97
Vanadium uptake by whole cells and isolated cell walls of the yeast Saccharomyces cerevisiae was studied. When orthovanadate was added to wild-type S. cerevisiae cells growing in rich medium, growth was inhibited as a function of the VO4
3- concentration and the growth was completely arrested at a concentration of 20 mM of VO4
3- in YEPD. Electron paramagnetic resonance (EPR) spectroscopy was used to obtain structural and dynamic information about the cell-associated paramagnetic vanadyl ion. The presence of EPR signals indicated that vanadate was reduced by whole cells to the vanadyl ion. On the contrary, no EPR signals were detected after interaction of vanadate with isolated cell walls. A mobile and an immobile species associated in cells with small chelates and with macromolecular sites, respectively, were identified. The value of rotational correlation time
r indicated the relative motional freedom at the macromolecular site. A strongly immobilized vanadyl species bound to polar sites mainly through coulombic attractions was detected after interaction of VO2+ ions with isolated cell walls. 相似文献
4.
Spartaco Gippoliti Andreina D’Alessandro 《Der Zoologische Garten (in deutscher Sprache / in German)》2013,82(3-4):113-128
This work reviews nearly 90 years of ape keeping and housing at the Giardino Zoologico in Rome, and offers an overview of the scientific research carried out on these primates. It may thus contribute to a better historical knowledge of primate zoo management in Italy. Furthermore, particular attention is paid to morphological aspects in orangutan physical development that should deserve further research. 相似文献
5.
6.
Buono Pasqualina D'Armiento Francesco P. Terzi Giuseppe Alfieri Andreina Salvatore Francesco 《Brain Cell Biology》2001,30(12):957-965
We have analyzed the distribution of aldolase A and C mRNAs and proteins in various areas of the human brain using Northern blot analyses and immunohistochemistry. Aldolase A mRNA expression was higher than aldolase C mRNA expression in all areas of the brain examined. Aldolase C mRNA expression was highest in the cerebellum. Aldolase C protein was present in well-delimited regions of the CNS, and was distributed in stripes in the Purkinje cell layer of the cerebellum, in the inferior olives and in the sensory neurons of the posterior horn of the spinal cord. The novel finding of aldolase C in well-delimited cell compartments of the human cerebellum and in several other areas of the CNS lends weight to the hypothesis that this protein exerts other functions (e.g. sensory transmission) besides those characteristic of a glycolytic enzyme. 相似文献
7.
Nicola Scichilone Andreina Bruno Roberto Marchese Antonio Maurizio Vignola Alkis Togias Vincenzo Bellia 《Respiratory research》2005,6(1):55
Background
We have previously shown that the bronchodilatory effect of deep inspiration is attenuated in individuals with COPD. This study was designed to investigate whether the impairment in this effect is associated with loss of alveolar attachments.Methods
We measured deep inspiration (DI)-induced bronchodilation in 15 individuals with and without COPD (67 ± 2.2 yrs of age, mean ± SEM) undergoing lobar resection for peripheral pulmonary nodule. Prior to surgery, we measured TLCO and determined the bronchodilatory effect of deep inspiration after constricting the airways with methacholine. The number of destroyed alveolar attachments, as well as airway wall area and airway smooth muscle area, were determined in tumor-free, peripheral lung tissue.Results
The bronchodilatory effect of deep inspiration correlated inversely with the % destroyed attachments (r = -0.51, p = 0.05) and directly with the airway smooth muscle area (r = 0.59, p = 0.03), but not with the total wall area (r = 0.39, p = 0.15).Conclusion
We postulate that attenuation of airway stretch due to loss of alveolar attachments contributes to the loss of the bronchodilatory effect of lung inflation in COPD. 相似文献8.
A Bordoni P L Biagi G Parenti Castelli S Hrelia C A Rossi G Lercker J C Izpisua T Barber J Cabo G Lenaz 《Membrane biochemistry》1989,8(1):11-18
Feeding rats a hyperlipidic diet in which animals were offered daily a variety of high-energy food resulted in a significant increase of serum free fatty acids and a decrease of phospholipids with respect to controls. On the contrary, there were no significant differences in erythrocyte membrane total lipid composition between the two groups. Erythrocyte membranes showed a significant decrease in saturated fatty acid content and a significant increase in (n-6) polyunsaturated fatty acid content; (n-3) polyunsaturated fatty acids significantly decreased. Membrane fluidity, investigated by fluorescence polarization of diphenylhexatriene, significantly increased in the erythrocyte membranes of the experimental group. These results seem compatible with the decreased saturated/unsaturated fatty acid ratio. A significant decrease of (Na+-K+)ATPase activity occurred in erythrocyte membranes of the experimental group rats with respect to the controls. 相似文献
9.
Federico Riu Roberta Ibba Stefano Zoroddu Simona Sestito Michele Lai Sandra Piras Luca Sanna Valentina Bordoni Luigi Bagella Antonio Carta 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2223
Introduction: Colchicine-binding site inhibitors are some of the most interesting ligands belonging to the wider family of microtubule-destabilising agents.Results: A novel series of 4′-fluoro-substituted ligands (5–13) was synthesised. The antiproliferative activity assays resulted in nM values for the new benzotriazole-acrylonitrile derivatives. Compound 5, the hit compound, showed an evident blockade of HeLa cell cycle in the G2-M phase, but also a pro-apoptotic potential, and an increase of early and late apoptotic cells in HeLa and MCF-7 cell cycle analysis. Confocal microscopy analysis showed a segmented shape and a collapse of the cytoskeleton, as well as a consistent cell shrinkage after administration of 5 at 100 nM. Derivative 5 was also proved to compete with colchicine at colchicine-binding site, lowering its activity against tubulin polymerisation. In addition, co-administration of 5 and doxorubicin in drug-resistant A375 melanoma cell line highlighted a synergic potential in terms of inhibition of cell viability.Discussion: The 4′-fluoro substitution of benzotriazole-acrylonitrile scaffold brought us a step forward in the optimisation process to obtain compound 5 as promising MDA antiproliferative agent at nanomolar concentration. 相似文献
10.
Bordoni R Consolandi C Castiglioni B Busti E Bernardi LR Battaglia C De Bellis G 《Nucleic acids research》2002,30(8):E34-E34
Enzyme-mediated reactions are a useful tool in mutation detection when using a microarray format. Discriminating probes attached to the surface of a DNA chip have to be accessible to target DNA and to the enzyme (ligase or polymerase) that catalyses the formation of a new phosphodiester bond. This requires an appropriate chemical platform. Recently, an oligonucleotide hairpin architecture incorporating multiple phosphorothioate moieties along the loop has been proposed as an effective approach to solid-phase minisequencing. We have explored in depth several variables (stem length, number of phosphorothioates, stem-loop architecture versus linear structure) involved in this strategy by using a solid-phase ligation reaction. Microarrays were fabricated either from aminosilyl-modified glass or from aminated polymeric surfaces made of poly-lysine. Both platforms were bromoacetylated and reacted with thiophosphorylated oligonucleotides. The resulting microarrays were tested using either a synthetic template or a PCR-amplified 16S rRNA genomic region as the target sequence. Our results confirm the robustness of the proposed chemistry. We extend its range of application to solid-phase ligation, demonstrating the effectiveness of multiple anchors and suggest that linear oligonucleotides incorporating multiple phosphorothioates are equivalent to their hairpin-structured counterparts. 相似文献