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991.
The mammalian target of rapamycin (mTOR) signaling pathway plays a critical role in growth and survival of BCR-ABL transformed cells. AMPK kinase is a metabolic sensor that exhibits suppressive effects on the mTOR pathway and negatively regulates mTOR activity. We report that AMPK activators, such as metformin and 5-aminoimidazole-4-carboxamide ribonucleotide, suppress activation of the mTOR pathway in BCR-ABL-expressing cells. Treatment with these inhibitors results in potent suppression of chronic myeloid leukemia leukemic precursors and Ph(+) acute lymphoblastic leukemia cells, including cells expressing the T315I-BCR-ABL mutation. Altogether, our data suggest that AMPK is an attractive target for the treatment of BCR-ABL-expressing malignancies and raise the potential for use of AMPK activators in the treatment of refractory chronic myeloid leukemia and Ph(+) acute lymphoblastic leukemia. 相似文献
992.
Temporally matched subpopulations of selectively interconnected principal neurons in the hippocampus
The extent to which individual neurons are interconnected selectively within brain circuits is an unresolved problem in neuroscience. Neurons can be organized into preferentially interconnected microcircuits, but whether this reflects genetically defined subpopulations is unclear. We found that the principal neurons in the main subdivisions of the hippocampus consist of distinct subpopulations that are generated during distinct time windows and that interconnect selectively across subdivisions. In two mouse lines in which transgene expression was driven by the neuron-specific Thy1 promoter, transgene expression allowed us to visualize distinct populations of principal neurons with unique and matched patterns of gene expression, shared distinct neurogenesis and synaptogenesis time windows, and selective connectivity at dentate gyrus-CA3 and CA3-CA1 synapses. Matched subpopulation marker genes and neuronal subtype markers mapped near clusters of olfactory receptor genes. The nonoverlapping matched timings of synaptogenesis accounted for the selective connectivities of these neurons in CA3. Therefore, the hippocampus contains parallel connectivity channels assembled from distinct principal neuron subpopulations through matched schedules of synaptogenesis. 相似文献
993.
994.
Annexins and S100 proteins constitute two multigenic families of Ca2+-modulated proteins that have been implicated in the regulation of both intracellular and extracellular activities. Some annexins can interact with certain S100 protein dimers thereby forming heterotetramers in which an S100 dimer crosslinks two copies of the partner annexin. It is suggested that S100 protein binding to an annexin might serve the function of regulating annexin function and annexin binding to an S100 protein might regulate S100 function. In the present study, annexin V, annexin VI (or ANXA5 and ANXA6, respectively, according to a novel nomenclature), S100A1 and S100B were analyzed for their subcellular localization in developing and adult avian skeletal muscles by confocal laser scanning microscopy, immunogold cytochemistry, and western blotting, and for their ability to form annexin-S100 heterocomplex in vivo by immunoprecipitation. These four proteins displayed distinct expression patterns, ANXA5 being the first to be expressed in myotubes (i.e. at embryonic day 8), followed by ANXA6 (at embryonic day 12) and S100A1 and S100B (between embryonic day 12 and embryonic day 15). The two annexins and the two S100 proteins were found associated to different extents with the sarcolemma, membranes of the sarcoplasmic reticulum, and putative transverse tubules where they appeared to be co-localized from embryonic day 18 onwards. No one of these proteins was found associated with the contractile apparatus of the sarcomeres. Immunoprecipitation studies indicated that ANXA6/S100A1 and ANXA6/S100B complexes formed in vivo. Whereas, ANXA5 was not recovered in S100A1 or S100B immunoprecipitates.From our data we suggest that: (i) ANXA5 and ANXA6, and S100A1 and S100B can be used as markers of skeletal muscle development; (ii) ANXA6 and S100A1 and S100B appear strategically located close to or on skeletal muscle membrane organelles that are critically involved in the regulation of Ca2+ fluxes, thus supporting previous in vitro observations implicating S100A1 and ANXA6 in the stimulation of Ca2+-induced Ca2+ release; and (iii) ANXA6/S100A1 and ANXA6/S100B complexes can form in vivo thereby regulating each other activities and/or acting in concert to regulate membrane-associated activities. 相似文献
995.
Severo D 《Soins. Psychiatrie》2012,(280):14-19
From the time of the asylum as an "instrument of healing" to the present day, history has shown the importance of architecture in the design and organisation of psychiatric care. It manifests itself in many different ways, from the organisation of the therapeutic area, the typologies of the care facilities, to the relationship with the town, the area and nature. There is a close link between the care facility and the town. 相似文献
996.
997.
Giovannetti A Mazzetta F Cavani A Pennino D Caprini E Ortona E Donato G Rosato E Salsano F Pierdominici M 《International journal of immunopathology and pharmacology》2012,25(2):503-511
Orofacial granulomatosis (OFG) is a clinicopathologic entity describing oral lesions with noncaseating granulomas including a spectrum of diseases such as the Melkersson-Rosenthal syndrome. The involvement of abnormal T-cell responses has been suggested in the pathogenesis of OFG although few and contrasting data are currently available on this issue. In a patient with OFG, we observed virtually complete CD4 and CD8 T-cell receptor (TCR) β-chain variable region (BV) repertoires at the lesion level and in circulation. However, oligoclonal profiles were found in CD4 and, to a greater extent, in CD8 subsets. These findings were seen in association with a massive peripheral T-cell activation, decreased naive T cells, reduced thymic output, altered cytokine production, and increased apoptosis. Our data, pointing to a random influx of T cells at the site of inflammation, argue against the hypothesis of a main allergen acting at the level of oral mucosa. The profound dysregulation of the peripheral T-cell compartment suggests that OFG should be regarded as a systemic disorder with localized manifestations. 相似文献
998.
De Fazio S Russo E Ammendola M Donato Di Paola E De Sarro G 《Current medicinal chemistry》2012,19(7):972-981
Glioblastoma multiforme (GBM) is a common and malignant primary brain tumor arising from glial precursors the survival of which is estimated to be about 14 months after diagnosis despite current standard care with radiotherapy, surgery, and chemotherapies. Therapeutic approaches were greatly improved in the last years; however, GBM still represents the most lethal subtype of glioma. Actually, it has been estimated that only about 3.4% of patients will survive at the most five years when obtaining the best outcome from treatment; however, this depends on tumor resistance, which is generally related to repairing radiation injury, and self- improving cell growth repair and survival. All GBMs recur after initial therapy, limiting patients ? survival at 20-25% within 1 year after diagnosis of recurrent disease. Moreover, for recurrent GBM response rates are less than 10% (ranging from 5% to 9%), and progression free survival at 6-month (PFS-6) rates ranges between 9% and 28% (median 15%). The development of targeted therapy based on tumor vascular blockade led to the approval of bevacizumab for recurrent or progressive glioblastoma, since it was proven that this offers a new opportunity for patients suffering from this malignancy. Bevacizumab is a recombinant antivascular monoclonal antibody binding to circulating Vascular Endothelial Growth Factor (VEGF) preventing this cytokine from reaching its receptors (VEGFR1 and VEGFR2) on endothelium, resulting in an inhibition of cells proliferation and vessels sprouting. The aim of this review is to address bevacizumab mode of action in malignant gliomas and provide a summary on currently available data on efficacy and safety. 相似文献
999.
Both sulfomucin-type intestinal metaplasia (ie, types II and III intestinal metaplasia, colonic-type intestinal metaplasia) and gastritis in Operative Link for Gastritis Assessment stages III and IV are associated with an increased risk of intestinal-type gastric cancer. This study aimed to verify the hypothesis that gastritis in Operative Link for Gastritis Assessment stages III and IV (both consistently associated with an increased cancer risk) is associated per se with types II and III intestinal metaplasia. Two hundred consecutive cases of atrophic gastritis (Operative Link for Gastritis Assessment stages I, II, III, and IV) were considered (50 cases for each stage). All cases were stained with high iron diamine, and intestinal metaplasia was subtyped accordingly (type I [ie, small-intestinal type] and types II and III). Helicobacter pylori status was also considered, distinguishing H pylori–positive versus H pylori–negative versus H pylori–eradicated patients. A significant association was found between intestinal metaplasia subtype and the Operative Link for Gastritis Assessment stage of gastritis (the higher the stage, the more the colonic-type of intestinal metaplasia, and vice versa; Wilcoxon, P = .001). The strength of the association between Operative Link for Gastritis Assessment stages and the 3 intestinal metaplasia subtypes was confirmed by logistic regression analysis (P < .001; odds ratio, 4.84; 95% confidence interval, 2.97-7.88). Intestinal metaplasia subtyping also correlated with the patient's age (Kruskal-Wallis, P = .001) and H pylori status (Fisher exact, P < .001). Operative Link for Gastritis Assessment staging incorporates the prognostic message obtainable from histochemical gastric mucin subtyping. 相似文献
1000.