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1.
A. Falconi D. Lorenzo S. Curti F. R. Morales M. Borde 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,181(2):143-151
The present study was designed to examine the synaptic events in neurons of the pacemaker nucleus of Gymnotus carapo during the increase in rate of the electric organ discharge following activation of Mauthner cells. Pacemaker and relay cells
were investigated using intracellular recordings which were performed under two different conditions: (1) with the pacemaker
nucleus spontaneously discharging and (2) after its activity was abolished by anesthesia. Mauthner axon activation induced
an increase in the rate of pacemaker cell discharges. This response was accompanied by an increase in the slope of the pacemaker
potential (up to 110%) and a depolarization of these cells. The discharges of relay cells followed one to one those of pacemaker
cells. In contrast to that observed in pacemaker cells, only brief depolarizing antidromic effects could be evoked in relay
cells after Mauthner axon activation. In quiescent pacemaker cells, Mauthner cell activation induced a prolonged (up to 500 ms)
depolarizing potential with an average amplitude of 1.92 ± 0.82 mV; its latency was 4.43 ± 1.14 ms. Our data indicate that,
within the pacemaker nucleus, the population of pacemaker cells is the only target for Mauthner cell-evoked, short-latency
excitatory synaptic actions.
Accepted: 1 March 1997 相似文献
2.
Mario Stampanoni Bassi Tommaso Nuzzo Luana Gilio Mattia Miroballo Alessia Casamassa Fabio Buttari Paolo Bellantonio Roberta Fantozzi Giovanni Galifi Roberto Furlan Annamaria Finardi Arianna De Rosa Anna Di Maio Francesco Errico Diego Centonze Alessandro Usiello 《Journal of neurochemistry》2021,159(5):857-866
3.
4.
S Papa M Vitale G Mazzotti R Rizzoli M Falconi A Bartoletti F A Manzoli 《Histochemistry》1988,89(3):241-245
A number of techniques are currently employed for the fractionation of heterogeneous cell populations or for the separation of cells in different phases of their cycle. With the development of osmotically inert colloidal silica particles media, density gradient centrifugation became an established method for the separation and purification of cells and subcellular particles. We have applied this technique to the separation of cycling from resting Friend erythroleukemia cells, to obtain purified populations for further biological assays. The flow cytometric analysis of DNA content of the different fractions obtained by the gradient and stained with Propidium Iodide (PI), showed the S compartment highly concentrated in the 1.073/77 g/ml interface, while the upper levels of the gradient were highly enriched of cells in G1 phase. Moreover, the dual parameter analysis of DNA content by means of Bromodeoxyuridine (BrdUrd) incorporation and PI staining, showed that part of the cells in the 1.067/73 fraction represented the early S phase even if their DNA level, measured on the basis of PI fluorescence was within the diploid cell cluster. This method seems to be suitable to obtain pure cell fractions even when dealing with numerically large populations. 相似文献
5.
Mattia Criscuoli Cristina Ulivieri Irene Filippi Sara Monaci Giuditta Guerrini Bianca Crifò Domiziana De Tommaso Giuliana Pelicci Cosima T. Baldari Cormac T. Taylor Fabio Carraro Antonella Naldini 《Journal of cellular physiology》2020,235(11):8058-8070
Hypoxia occurs in physiological and pathological conditions. T cells experience hypoxia in pathological and physiological conditions as well as in lymphoid organs. Indeed, hypoxia-inducible factor 1α (HIF-1α) affects T cell survival and functions. Rai, an Shc family protein member, exerts pro-survival effects in hypoxic neuroblastoma cells. Since Rai is also expressed in T cells, we here investigated its role in hypoxic T cells. In this work, hypoxia differently affected cell survival, proapoptotic, and metabolic programs in T cells, depending upon Rai expression. By using Jurkat cells stably expressing Rai and splenocytes from Rai−/−mice, we demonstrated that Rai promotes T cell survival and affects cell metabolism under hypoxia. Upon exposure to hypoxia, Jurkat T cells expressing Rai show (a) higher HIF-1α protein levels; (b) a decreased cell death and increased Akt/extracellular-signal-regulated kinase phosphorylation; (c) a decreased expression of proapoptotic markers, including caspase activities and poly(ADP-ribose) polymerase cleavage; (d) an increased glucose and lactate metabolism; (e) an increased activation of nuclear factor-kB pathway. The opposite effects were observed in hypoxic splenocytes from Rai−/−mice. Thus, Rai plays an important role in hypoxic signaling and may be relevant in the protection of T cells against hypoxia. 相似文献
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7.
Manel Puig-Domingo Raúl M. Luque Jordi L. Reverter Laura M. López-Sánchez Manuel D. Gahete Michael D. Culler Gonzalo Díaz-Soto Francisco Lome?a Mattia Squarcia José Luis Mate Mireia Mora Laureano Fernández-Cruz Oscar Vidal Antonio Alastrué Jose Balibrea Irene Halperin Dídac Mauricio Justo P. Casta?o 《PloS one》2014,9(1)
Somatostatin receptors (ssts) are expressed in thyroid cancer cells, but their biological significance is not well understood. The aim of this study was to assess ssts in well differentiated (WDTC) and poorly differentiated thyroid cancer (PDTC) by means of imaging and molecular tools and its relationship with the efficacy of somatostatin analog treatment. Thirty-nine cases of thyroid carcinoma were evaluated (20 PDTC and 19 WDTC). Depreotide scintigraphy and mRNA levels of sst-subtypes, including the truncated variant sst5TMD4, were carried out. Depreotide scans were positive in the recurrent tumor in the neck in 6 of 11 (54%) PDTC, and in those with lung metastases in 5/11 cases (45.4%); sst5TMD4 was present in 18/20 (90%) of PDTC, being the most densely expressed sst-subtype, with a 20-fold increase in relation to sst2. In WDTC, sst2 was the most represented, while sst5TMD4 was not found; sst2 was significantly increased in PDTC in comparison to WDTC. Five depreotide positive PDTC received octreotide for 3–6 months in a pilot study with no changes in the size of the lesions in 3 of them, and a significant increase in the pulmonary and cervical lesions in the other 2. All PDTC patients treated with octreotide showed high expression of sst5TMD4. ROC curve analysis demonstrated that only sst5TMD4 discriminates between PDTC and WDTC. We conclude that sst5TMD4 is overexpressed in PDTC and may be involved in the lack of response to somatostatin analogue treatment. 相似文献
8.
Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
9.
10.
Emre Brookes Borries Demeler Camillo Rosano Mattia Rocco 《European biophysics journal : EBJ》2010,39(3):423-435
The interpretation of solution hydrodynamic data in terms of macromolecular structural parameters is not a straightforward
task. Over the years, several approaches have been developed to cope with this problem, the most widely used being bead modeling
in various flavors. We report here the implementation of the SOMO (SOlution MOdeller; Rai et al. in Structure 13:723–734,
2005) bead modeling suite within one of the most widely used analytical ultracentrifugation data analysis software packages, UltraScan
(Demeler in Modern analytical ultracentrifugation: techniques and methods, Royal Society of Chemistry, UK, 2005). The US-SOMO version is now under complete graphical interface control, and has been freed from several constraints present
in the original implementation. In the direct beads-per-atoms method, virtually any kind of residue as defined in the Protein
Data Bank (e.g., proteins, nucleic acids, carbohydrates, prosthetic groups, detergents, etc.) can be now represented with
beads whose number, size and position are all defined in user-editable tables. For large structures, a cubic grid method based
on the original AtoB program (Byron in Biophys J 72:408–415, 1997) can be applied either directly on the atomic structure, or on a previously generated bead model. The hydrodynamic parameters
are then computed in the rigid-body approximation. An extensive set of tests was conducted to further validate the method,
and the results are presented here. Owing to its accuracy, speed, and versatility, US-SOMO should allow to fully take advantage
of the potential of solution hydrodynamics as a complement to higher resolution techniques in biomacromolecular modeling. 相似文献