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1.
Antonella Minelli Giovanna Floridia Elena Rossi Maurizio Clementi Romano Tenconi Lamberto Camurri Franca Bernardi Heidi Hoeller Carlo Previde Re Paola Maraschio Stephen Wood Orsetta Zuffardi Cesare Danesino 《Human genetics》1993,92(4):391-396
Ten patients with inverted duplication of 8p (inv dup 8p) were studied with cytogenetic, biochemical and molecular techniques. The duplication for the region 8p12-p22 was always associated with a deletion of the locus D8S7 (mapped in 8p23.1) as demonstrated with the probe pSW50 by both in situ hybridization and Southern blot. Restriction fragment length polymorphisms detected by probes pSW50 (1 case) and by pG2LPL35 (locus LPL) (two cases) were informative as to a maternal origin of the anomaly. The activity of glutathione reductase, whose gene maps in the duplicated region at 8p21.1, was increased in all patients. The recognizable phenotype of inv dup 8p includes neonatal hypotonia, prominent forehead, large mouth with everted lower lip, abnormally shaped large ears, brain malformations and severe mental retardation. Our findings indicate that the chromosome rearrangement is homogeneous at least for the presence of the deletion and support the hypothesis of a common mechanism of origin. 相似文献
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Yuguo Yu Thomas S. McTavish Michael L. Hines Gordon M. Shepherd Cesare Valenti Michele Migliore 《PLoS computational biology》2013,9(3)
In the olfactory bulb, lateral inhibition mediated by granule cells has been suggested to modulate the timing of mitral cell firing, thereby shaping the representation of input odorants. Current experimental techniques, however, do not enable a clear study of how the mitral-granule cell network sculpts odor inputs to represent odor information spatially and temporally. To address this critical step in the neural basis of odor recognition, we built a biophysical network model of mitral and granule cells, corresponding to 1/100th of the real system in the rat, and used direct experimental imaging data of glomeruli activated by various odors. The model allows the systematic investigation and generation of testable hypotheses of the functional mechanisms underlying odor representation in the olfactory bulb circuit. Specifically, we demonstrate that lateral inhibition emerges within the olfactory bulb network through recurrent dendrodendritic synapses when constrained by a range of balanced excitatory and inhibitory conductances. We find that the spatio-temporal dynamics of lateral inhibition plays a critical role in building the glomerular-related cell clusters observed in experiments, through the modulation of synaptic weights during odor training. Lateral inhibition also mediates the development of sparse and synchronized spiking patterns of mitral cells related to odor inputs within the network, with the frequency of these synchronized spiking patterns also modulated by the sniff cycle. 相似文献
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Annamaria Tonazzi Cristina Mantovani Matilde Colella Giorgio Terenghi Cesare Indiveri 《Neurochemical research》2013,38(12):2535-2541
The carnitine/acylcarnitine transporter is a transport system whose function is essential for the mitochondrial β-oxidation of fatty acids. Here, the presence of carnitine/acylcarnitine carrier (CACT) in nervous tissue and its sub-cellular localization in dorsal root ganglia (DRG) neurons have been investigated. Western blot analysis using a polyclonal anti-CACT antibody produced in our laboratory revealed the presence of CACT in all the nervous tissue extracts analyzed. Confocal microscopy experiments performed on fixed and permeabilized DRG neurons co-stained with the anti-CACT antibody and the mitochondrial marker MitoTracker Red clearly showed a mitochondrial localization for the carnitine/acylcarnitine transporter. The transport activity of CACT from DRG extracts reconstituted into liposomes was about 50 % in respect to liver extracts. The experimental data here reported represent the first direct evidence of the expression of the carnitine/acylcarnitine transporter in sensory neurons, thus supporting the existence of the β-oxidation pathway in these cells. 相似文献
6.
Palynological studies of the Leffe Basin lacustrine deposits (Lombard Pre‐Alps, Italy) reveal a succession of deciduous mesophytic arboreal communities, coniferous forests and brief phases of withdrawal of arboreal taxa. The pollen record can be easily correlated with a previous pollen diagram by Lona (1950). However, contrary to his interpretation, we believe that the cyclicity shown by vegetation dynamics cannot be correlated with the major glacial events that occurred in the Southern Alps, but perhaps with interglacial‐glacial cycles of moderate amplitude. 相似文献
7.
Claudio Battilocchio Giovanna Poce Salvatore Alfonso Giulio Cesare Porretta Sara Consalvi Lidia Sautebin Simona Pace Antonietta Rossi Carla Ghelardini Lorenzo Di Cesare Mannelli Silvia Schenone Antonio Giordani Luigia Di Francesco Paola Patrignani Mariangela Biava 《Bioorganic & medicinal chemistry》2013,21(13):3695-3701
We report the synthesis and bio-pharmacological evaluation of a class of pyrrole derivatives featuring a small appendage fragment (carbaldehyde, oxime, nitrile) on the central core. Compound 1c proved to be extremely effective in vivo, showing an interesting anti-nociceptic profile that is comparable to reference compounds already marketed, hence representing a great stimulus for a further improvement of this class of molecules. 相似文献
8.
J. Ramon De Lucas J. Ramon De Lucas Cesare Indiveri J. Ramon De Lucas Cesare Indiveri Annamaria Tonazzi 《Molecular membrane biology》2013,30(2):152-163
The mitochondrial carnitine/acylcarnitine carrier (CAC) is characterized by the presence of a distinct motif, RXXPANAAXF, within its sixth transmembrane α-helix. In this study, we analysed the role of the amino acids of this motif in the structure-function relationships of the human CAC by using two complementary approaches. First, we performed functional analysis in the model fungus Aspergillus nidulans of selected mutations with structural and functional relevance. Second, similar mutant human CACs were biochemically characterized after their reconstitution into liposomes. Both analyses have provided relevant information on the importance and role of the CAC motif residues in the activity and metabolic function of CAC. Only the two adjacent alanines, Ala281 and Ala282 in the human CAC, have been found not to be crucial for transport activity and in vivo function. Results obtained from amino acid substitutions of residues Arg275, Asn280 and Phe284 of human CAC together with structural analysis using molecular modelling of the carrier suggest that R275, N280 and F284 are involved in substrate binding during acylcarnitine/carnitine translocation. Furthermore, functional analysis of mutations of residues Pro278 and Ala279 in A. nidulans, together with kinetic data in reconstituted liposomes, suggest a predominant structural role for these amino acids. 相似文献
9.
Gennaro Esposito Megan Garvey Vera Alverdi Fabio Pettirossi Alessandra Corazza Federico Fogolari Maurizio Polano P. Patrizia Mangione Sofia Giorgetti Monica Stoppini Agata Rekas Vittorio Bellotti Albert J. R. Heck John A. Carver 《The Journal of biological chemistry》2013,288(24):17844-17858
The interaction at neutral pH between wild-type and a variant form (R3A) of the amyloid fibril-forming protein β2-microglobulin (β2m) and the molecular chaperone αB-crystallin was investigated by thioflavin T fluorescence, NMR spectroscopy, and mass spectrometry. Fibril formation of R3Aβ2m was potently prevented by αB-crystallin. αB-crystallin also prevented the unfolding and nonfibrillar aggregation of R3Aβ2m. From analysis of the NMR spectra collected at various R3Aβ2m to αB-crystallin molar subunit ratios, it is concluded that the structured β-sheet core and the apical loops of R3Aβ2m interact in a nonspecific manner with the αB-crystallin. Complementary information was derived from NMR diffusion coefficient measurements of wild-type β2m at a 100-fold concentration excess with respect to αB-crystallin. Mass spectrometry acquired in the native state showed that the onset of wild-type β2m oligomerization was effectively reduced by αB-crystallin. Furthermore, and most importantly, αB-crystallin reversibly dissociated β2m oligomers formed spontaneously in aged samples. These results, coupled with our previous studies, highlight the potent effectiveness of αB-crystallin in preventing β2m aggregation at the various stages of its aggregation pathway. Our findings are highly relevant to the emerging view that molecular chaperone action is intimately involved in the prevention of in vivo amyloid fibril formation. 相似文献
10.
M.-E. Cohen C. Pellot-Barakat J.-M. Tacchella M. Lefort A. De Cesare J. Lebenberg N. Souedet O. Lucidarme T. Delzescaux F. Frouin 《IRBM》2013,34(4-5):283-286
ObjectivesDynamic X-ray computed tomography with contrast agent injection allows quantifying the tumor response to an antiangiogenic treatment. For hepatic tumors, it is crucial to correct for respiratory movements to ensure a good quantification of perfusion parameters.Material and MethodsTwo registration models were tested on eight dynamic exams: 1) rigid model and 2) elastic model based on Free Form Deformation. Each exam included about 50 volumes acquired under free-breathing conditions. The registration methods were quantitatively and automatically evaluated by defining a global score. This score was based on a Dice index and measured the superimposition rate between corresponding bony structures of different frames of the temporal exam.ResultsBefore registration, the mean value of the score was 0.78. After rigid registration, these values were globally lower with an average of 0.73. After elastic registration, a mean score of 0.90 was reached which was much higher than before registration.ConclusionThis automatic evaluation showed its interest for controlling the quality of dynamic CT registrations. It also helped proving that elastic methods are much more efficient than rigid methods for registering abdominal dynamic volumes, when considering the whole field of view. 相似文献