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排序方式: 共有1139条查询结果,搜索用时 12 毫秒
91.
Claudia Bello Michele Cea Giovanna Dal Bello Anna Garuti Ilaria Rocco Gabriella Cirmena Eva Moran Aimable Nahimana Michel A. Duchosal Floriana Fruscione Paolo Pronzato Francesco Grossi Franco Patrone Alberto Ballestrero Marc Dupuis Bernard Sordat Alessio Nencioni Pierre Vogel 《Bioorganic & medicinal chemistry》2010,18(9):3320-3334
Novel α-mannosidase inhibitors of the type (2R,3R,4S)-2-({[(1R)-2-hydroxy-1-arylethyl]amino}methyl)pyrrolidine-3,4-diol have been prepared and assayed for their anticancer activities. Compound 30 with the aryl group = 4-trifluoromethylbiphenyl inhibits the proliferation of primary cells and cell lines of different origins, irrespective of Bcl-2 expression levels, inducing a G2/Mcell cycle arrest and by modification of genes involved in cell cycle progression and survival. 相似文献
92.
Patrizia Casalbore Ilaria Barone Armando Felsani Igea D'Agnano Fabrizio Michetti Giulio Maira Carlo Cenciarelli 《Journal of cellular physiology》2010,224(3):710-721
In vitro expansion of neural stem cells (NSC) lentivirally transduced with human BDNF may serve as better cellular source for replacing degenerating neurons in disease, trauma and toxic insults. In this study, we evaluate the functional role of forced BDNF expression by means of NSC (M3GFP‐BDNF) obtained from cerebral cortex of 1‐day‐old mice respect to NSC‐control (M3GFP). We find that M3GFP‐BDNF induced to differentiate significantly accumulate BDNF and undergone to high potassium‐mediated depolarization, show rapid BDNF recycle and activation of Trk receptors signaling. Differentiated M3GFP‐BDNF exhibit neurons and oligodendrocytes with extended processes although quantitative analyses of NSC‐derived cell lineages show none statistical significance between both cell populations. Moreover, those cells show a significant induction of neuronal and oligodendroglial markers by RT‐PCR and Western blot respect to M3GFP, such as βIII‐Tubulin, microtubule associated protein 2 (MAP2), neurofilaments heavy (NF‐H), oligodendroglial myelin glycoprotein (OMG) and some molecules involved in glutamatergic synapse maturation, such as receptors tyrosine kinases (TRKs), post‐synaptic density (PSD‐95) and N‐methyl‐D ‐aspartate receptors 2 A/B (NMDA2A/B). After treatment with the neurotoxicant trimethyltin (TMT), differentiated M3GFP‐BDNF exhibit an attenuation of cellular damage which correlates with a significant activation of MAPK and PI3K/Akt signaling and delayed activation of death signals, while on M3GFP, TMT induces a significant reduction of cell survival, neuronal differentiation and concomitant earlier activation of cleaved caspase‐3. We demonstrate that overexpression of BDNF firmly regulate cell survival and differentiation of NSC and protects differentiated NSC against TMT‐induced neurotoxicity through the PI3K/Akt and MAPK signaling pathways. J. Cell. Physiol. 224: 710–721, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Galluzzi F Stagi S Parpagnoli M Losi S Pagnini I Favelli F Chiarelli F Salti R Seminara S 《Hormone research》2006,66(6):285-288
INTRODUCTION: Oral clonidine is one of the most frequent drugs used for the diagnosis of growth hormone deficiency (GHD), but the duration of the test, depending on which European centres use it, is not uniform and can vary from 120 to 150 min or even 180 min. SUBJECTS AND METHODS: To standardize this test, evaluating the possibility to shorten it to 90 min, we investigated the response of GH to the oral clonidine test in 291 children evaluated for short stature (height <-2 SD). Of these, 164 were diagnosed as idiopathic short stature (ISS) and 127 as GHD. In these patients, we calculated: (1) the frequency distribution of the GH peaks to clonidine in GHD and in ISS at various times; (2) the percentage of GH peaks to clonidine before and after 90 min in all and in ISS children; (3) the percentage of the first GH value >or=10 ng/ml before 90 min and after 90 min in ISS. RESULTS: GH peak distribution varied between 30 and 180 min, even though the vast majority of peaks occurred between 30 and 60 min. There was no significant difference (p > 0.05) in the peak distribution between ISS and GHD children. The percentages of GH peaks within 90 min were 92.1% in all children and 95.7% in ISS. If considering the first value of GH >or=10 ng/ml this last percentage reaches 96.3%. CONCLUSION: Our study suggests that the oral clonidine test can be administered for only 90 min without significantly changing its validity. This test should be standardized at 90 min in European protocols just as in those currently used in the USA in order to reduce the discomfort of patients and the cost of this diagnostic procedure. 相似文献
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HIV-1 Tat regulates endothelial cell cycle progression via activation of the Ras/ERK MAPK signaling pathway 总被引:2,自引:0,他引:2
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Toschi E Bacigalupo I Strippoli R Chiozzini C Cereseto A Falchi M Nappi F Sgadari C Barillari G Mainiero F Ensoli B 《Molecular biology of the cell》2006,17(4):1985-1994
Tat, the transactivator of HIV-1 gene expression, is released by acutely HIV-1-infected T-cells and promotes adhesion, migration, and growth of inflammatory cytokine-activated endothelial and Kaposi's sarcoma cells. It has been previously demonstrated that these effects of Tat are due to its ability to bind through its arginine-glycine-aspartic (RGD) region to the alpha5beta1 and alphavbeta3 integrins. However, the signaling pathways linking Tat to the regulation of cellular functions are incompletely understood. Here, we report that Tat ligation on human endothelial cells results in the activation of the small GTPases Ras and Rac and the mitogen-activated protein kinase ERK, specifically through its RGD region. In addition, we demonstrated that Tat activation of Ras, but not of Rac, induces ERK phosphorylation. We also found that the receptor proximal events accompanying Tat-induced Ras activation are mediated by tyrosine phosphorylation of Shc and recruitment of Grb2. Moreover, Tat enabled endothelial cells to progress through the G1 phase in response to bFGF, and the process is linked to ERK activation. Taken together, these data provide novel evidence about the ability of Tat to activate the Ras-ERK cascade which may be relevant for endothelial cell proliferation and for Kaposi's sarcoma progression. 相似文献
97.
Malavasi F Deaglio S Ferrero E Funaro A Sancho J Ausiello CM Ortolan E Vaisitti T Zubiaur M Fedele G Aydin S Tibaldi EV Durelli I Lusso R Cozno F Horenstein AL 《Molecular medicine (Cambridge, Mass.)》2006,12(11-12):334-341
This paper reviews some of the results and the speculations presented at the Torino CD38 Meeting in June, 2006 and focused on CD38 and CD157 seen as a family of molecules acting as surface receptors of immune cells. This partisan view was adopted in the attempt to combine the enzymatic functions with what the immunologists consider key functions in different cell models. At the moment, it is unclear whether the two functions are correlated, indifferent, or independent. Here we present conclusions inferred exclusively on human cell models, namely T and B lymphocytes, dendritic cells, and granulocytes. As an extra analytical tool, we try to follow in the history of life when the enzymatic and receptorial functions were generated, mixing ontogeny, membrane localization, and cell anchorage. 相似文献
98.
Romani R Corsi I Bonacci S Focardi S De Medio GE De Santis A Incarnato F Giovannini E Rosi G 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2006,145(2):188-196
We describe the acetylcholinesterase polymorphisms of two bivalve molluscs, Adamussium colbecki and Pecten jacobaeus. The research was aimed to point out differences in the expression of pesticide-resistant acetylcholinesterase forms in organisms living in different ecosystems such as the Ross Sea (Antarctica) and the Mediterranean Sea. In A. colbecki, distinct acetylcholinesterase molecular forms were purified and characterized from spontaneously soluble, low-salt-soluble and low-salt-Triton extracts from adductor muscle and gills. They consist of two non-amphiphilic acetylcholinesterases (G(2), G(4)) and an amphiphilic-phosphatidylinositol-membrane-anchored form (G(2)); a further amphiphilic-low-salt-soluble G(2) acetylcholinesterase was found only in adductor muscle. In the corresponding tissues of P. jacobaeus, we found a non-amphiphilic G(4) and an amphiphilic G(2) acetylcholinesterase; amphiphilic-low-salt-soluble acetylcholinesterases (G(2)) are completely lacking. Such results are related with differences in cell membrane lipid compositions. In both scallops, all non-amphiphilic AChEs are resistant to used pesticides. Differently, the adductor muscle amphiphilic forms are resistant to carbamate eserine and organophosphate diisopropylfluorophosphate, but sensitive to organophoshate azamethiphos. In the gills of P. jacobaeus, amphiphilic G(2) forms are sensitive to all three pesticides, while the corresponding forms of A. colbecki are sensitive to eserine and diisopropylfluorophosphate, but resistant to azamethiphos. Results indicate that organophosphate and/or carbamate resistant AChE forms are present in species living in far different and far away environments. The possibility that these AChE forms could have ensued from a common origin and have been spread globally by migration is discussed. 相似文献
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Marazziti D Baroni S Pirone A Giannaccini G Betti L Schmid L Vatteroni E Palego L Borsini F Bordi F Piano I Gargini C Castagna M Catena-Dell'osso M Lucacchini A 《Neurochemical research》2012,37(5):920-927
The aim of this study was to investigate the distribution of serotonin (5-HT) receptors of type 6 (5-HT(6)) in postmortem human prefrontal cortex, striatum and hippocampus. The brain samples were obtained from 6 subjects who had died for causes not involving primarily or secondarily the CNS. The 5-HT(6) receptor distribution was explored by the [(125)I]SB-258585 binding to brain membranes followed by the pharmacological characterization, where possible, and by autoradiographic, immunohistochemical and immunofluorescence evaluations. A specific and saturable [(125)I]SB-258585 binding was detected in striatum only, with a pharmacological characterization consistent with that of a 5-HT(6) receptor. The autoradiography showed the presence of a specific [(125)I]SB-258585 binding distributed homogeneously in caudate, putamen and accumbens. The immunohistochemistry, carried out in the striatum only, coupled with the immunofluorescence with glial fibrillary acidic protein (GFAP) and parvalbumin (PV) showed the co-localization of 5-HT(6) receptor with PV, while indicating that this receptor subtype was expressed in neurons and not in astrocytes. Taken together, the present findings showed the presence of a higher density of 5-HT(6) receptors, as labeled by [(125)I]SB-258585, in striatum than in hippocampus and prefrontal cortex, and specifically within the neuronal body. In addition, they would suggest that striatum is one of the major potential CNS targets linked to 5-HT(6) receptor modulation. 相似文献