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991.
Julia Jungnickel Kristina Haase Jens Konitzer Marco Timmer Claudia Grothe 《Developmental neurobiology》2006,66(9):940-948
Basic fibroblast growth factor (FGF‐2) is expressed in the peripheral nervous system and is up‐regulated after nerve lesion. It has been demonstrated that administration of FGF‐2 protects neurons from injury‐induced cell death and promotes axonal regrowth. Using transgenic mice over‐expressing FGF‐2 (TgFGF‐2), we addressed the importance of endogenously generated FGF‐2 on sensory neuron loss and sciatic nerve regeneration. After sciatic nerve transection, wild‐type and transgenic mice showed the same degree of cell death in L5 spinal ganglia. Also, the number of chromatolytic, eccentric, and pyknotic sensory neurons was not changed under elevated levels of FGF‐2. Morphometric evaluation of intact nerves from TgFGF‐2 mice revealed no difference in number and size of myelinated fibers compared to wild‐type mice. One week after crush injury, the number of regenerated axons was doubled and the myelin thickness was significantly smaller in transgenic mice. After 2 and 4 weeks, morphometric analysis and functional tests revealed no differences in recovery of sensory and motor nerve fibers. To study the role of FGF‐2 over‐expression on Schwann cell proliferation during the early regeneration process, we used BrdU‐labeling to mark dividing cells. In transgenic mice, the number of proliferating cells was significantly increased distal to the crush site compared to wild‐types. We propose that endogenously synthesized FGF‐2 influences early peripheral nerve regeneration by regulating Schwann cell proliferation, axonal regrowth, and remyelination. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 相似文献
992.
Threshold-dependent BMP-mediated repression: a model for a conserved mechanism that patterns the neuroectoderm 总被引:1,自引:0,他引:1
Subdivision of the neuroectoderm into three rows of cells along the dorsal-ventral axis by neural identity genes is a highly conserved developmental process. While neural identity genes are expressed in remarkably similar patterns in vertebrates and invertebrates, previous work suggests that these patterns may be regulated by distinct upstream genetic pathways. Here we ask whether a potential conserved source of positional information provided by the BMP signaling contributes to patterning the neuroectoderm. We have addressed this question in two ways: First, we asked whether BMPs can act as bona fide morphogens to pattern the Drosophila neuroectoderm in a dose-dependent fashion, and second, we examined whether BMPs might act in a similar fashion in patterning the vertebrate neuroectoderm. In this study, we show that graded BMP signaling participates in organizing the neural axis in Drosophila by repressing expression of neural identity genes in a threshold-dependent fashion. We also provide evidence for a similar organizing activity of BMP signaling in chick neural plate explants, which may operate by the same double negative mechanism that acts earlier during neural induction. We propose that BMPs played an ancestral role in patterning the metazoan neuroectoderm by threshold-dependent repression of neural identity genes. 相似文献
993.
994.
Stefanie F. Geiselhardt Stefan Lamm Claudia Gack Klaus Peschke 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2010,196(5):369-378
Species of various insect orders possess specialised tarsal adhesive structures covered by a thin liquid film, which is deposited
in the form of footprints. This adhesive liquid has been suggested to be chemically and physiologically related to the epicuticular
lipid layer, which naturally covers the body of insects and acts as the prime barrier to environmental stresses, such as desiccation.
The functional efficiency of the layer, however, is jeopardised by partial melting that may occur at physiological temperatures.
In this study, light microscopic images of elytral prints show that the epicuticular lipid layer of the Colorado potato beetle
Leptinotarsa decemlineata actually is partially liquid and chemical investigations reveal the high similarity of the epicuticular hydrocarbon pattern
and the tarsal liquid. By means of chemical manipulation of the surface hydrocarbon composition of live beetles, the substance
exchange between their tarsal adhesive hairs and the body surface is monitored. Histological sections of L. decemlineata tarsi, furthermore, reveal glandular cells connected to individual adhesive setae and departing from these results, an idea
of a general mechanism of tarsal secretion is developed and discussed in a functional–ecological context. 相似文献
995.
Ana O. Fagundes Maira R. Aguiar Claudia S. Aguiar Giselli Scaini Monique U. Sachet Nayara M. Bernhardt Gislaine T. Rezin Samira S. Valvassori João Quevedo Emilio L. Streck 《Neurochemical research》2010,35(11):1675-1680
Methylphenidate is commonly used for the treatment of attention deficit/hyperactivity disorder. There are still few works
regarding the effects of methylphenidate on brain energy metabolism. Thus, in the present study we evaluated the effect of
chronic administration of methylphenidate on the activities of mitochondrial respiratory chain complexes I and III in the
brain of young rats. The effect of acute administration of methylphenidate on mitochondrial respiratory chain complexes I,
II, III and IV in the brain of young rats was also investigated. For acute administration, a single injection of methylphenidate
was given to rats on postnatal day 25. For chronic administration, methylphenidate injections were given starting at postnatal
day 25 once daily for 28 days. Our results showed that complexes I and III were not affected by chronic administration of
methylphenidate. Moreover, the acute administration of methylphenidate decreased complex I activity in cerebellum and prefrontal
cortex, whereas complexes II, III and IV were not altered. 相似文献
996.
New gene expressed in prostate: a potential target for T cell-mediated prostate cancer immunotherapy
Vittore Cereda Diane J. Poole Claudia Palena Sudipto Das Tapan K. Bera Cinzia Remondo James L. Gulley Philip M. Arlen Junko Yokokawa Ira Pastan Jeffrey Schlom Kwong Y. Tsang 《Cancer immunology, immunotherapy : CII》2010,59(1):63-71
New gene expressed in prostate (NGEP) is a prostate-specific gene encoding either a small cytoplasmic protein (NGEP-S) or a larger polytopic membrane protein (NGEP-L). NGEP-L expression is detectable only in prostate cancer, benign prostatic hyperplasia and normal prostate. We have identified an HLA-A2 binding NGEP epitope (designated P703) which was used to generate T cell lines from several patients with localized and metastatic prostate cancer. These T cell lines were able to specifically lyse HLA-A2 and NGEP-expressing human tumor cells. NGEP-P703 tetramer binding assays demonstrated that metastatic prostate cancer patients had a higher frequency of NGEP-specific T cells when compared with healthy donors. Moreover, an increased frequency of NGEP-specific T cells was detected in the peripheral blood mononuclear cells of prostate cancer patients post-vaccination with a PSA-based vaccine, further indicating the immunogenicity of NGEP. These studies thus identify NGEP as a potential target for T cell-mediated immunotherapy of prostate cancer. 相似文献
997.
Casoni GL Ulivi P Mercatali L Chilosi M Tomassetti S Romagnoli M Ravaglia C Gurioli C Gurioli C Zoli W Silvestrini R Poletti V 《The International journal of biological markers》2010,25(4):229-235
Idiopathic pulmonary fibrosis (IPF) is difficult to diagnose because of numerous interstitial lung diseases with similar symptoms. As serum DNA has proven useful for early lung cancer detection, we aimed to define the relevance of this marker in discriminating IPF from other fibrotic and nonfibrotic/nonmalignant lung diseases. DNA was quantified in 191 subjects: 64 healthy individuals, 58 patients with IPF, 17 patients with nonspecific pulmonary fibrosis (13 idiopathic nonspecific interstitial pneumonia, 4 chronic hypersensitivity pneumonitis), and 52 patients with other diffuse/nonmalignant lung diseases. The median value of free DNA in IPF patients was 61.1 ng/mL (range 7.1-405), which was significantly higher than that of healthy donors (median 6.8, range 2.2-184) (p<0.001) and that of patients with other diffuse/nonmalignant lung diseases (median 28.0, range 4.2-281) (p=0.004). The area under the ROC curve was 0.926 (95% CI 0.879-0.973) when IPF patients were compared with healthy donors, and 0.702 (95% CI 0.609-0.796) when a comparison was made with non-IPF pulmonary diseases. In conclusion, we observed significantly higher levels of free circulating DNA in patients with IPF than in those with other fibrotic or diffuse/nonmalignant lung diseases. 相似文献
998.
Gianfabio Giorgioni Dario Ambrosini Cristian Vesprini Alan Hudson Cinzia Nasuti Antonio Di Stefano Piera Sozio Osele Ciampi Barbara Costa Claudia Martini Antonio Carrieri Giuseppe Carbonara Christoph Enzensperger Maria Pigini 《Bioorganic & medicinal chemistry》2010,18(19):7085-7091
Based on the well known biological versatility of the imidazoline nucleus, we prepared the novel derivatives 3a–k inspired by 2-BFI scaffold to assess imidazoline molecules as D2-like dopamine receptor ligands. Conservative chemical modifications of the lead structure, such as the introduction of an hydroxy group in the aromatic ring alone or associated with N-benzyl substitution, provided partial (3f) or nearly full (3e and 3h) agonists, all endowed with D2-like potency comparable to that of dopamine. 相似文献
999.
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
1000.
Pierfrancesco Biagini Claudio Biancalani Alessia Graziano Nicoletta Cesari Maria Paola Giovannoni Agostino Cilibrizzi Vittorio Dal Piaz Claudia Vergelli Letizia Crocetti Maurizio Delcanale Elisabetta Armani Andrea Rizzi Paola Puccini Paola Maria Gallo Daniele Spinabelli Paola Caruso 《Bioorganic & medicinal chemistry》2010,18(10):3506-3517
A series of pyrazoles and pyrazolo[3,4-d]pyridazinones were synthesized and evaluated for their PDE4 inhibitory activity. All the pyrazoles were found devoid of activity, whereas some of the novel pyrazolo[3,4-d]pyridazinones showed good activity as PDE4 inhibitors. The most potent compounds in this series showed an IC50 in the nanomolar range. The ability to inhibit TNF-α release in human PBMCs was determined for two representative compounds, finding values in the sub-micromolar range. SARs studies demonstrated that the best arranged groups around the heterocyclic core are 2-chloro-, 2-methyl- and 3-nitrophenyl at position 2, an ethyl ester at position 4 and a small alkyl group at position 6. Molecular modeling studies performed on a representative compound allowed to define its binding mode to the PDE4B isoform. 相似文献