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131.
Galtieri A Tellone E Romano L Misiti F Bellocco E Ficarra S Russo A Di Rosa D Castagnola M Giardina B Messana I 《Biochimica et biophysica acta》2002,1564(1):214-218
Sulfate transport by band-3 protein in adult human erythrocytes was shown to be modulated by oxygen pressure. In particular, a higher transport activity was measured under high oxygen pressure than at low one (0.0242+/-0.0073 vs. 0.0074+/-0.0010 min(-1)). Other factors, such as magnesium ions and orthovanadate, which can indirectly affect the binding properties of the cytoplasmic domain of band 3 (cdb3), influence significantly the anion exchanger activity. No effect of oxygen pressure on sulfate transport was found in chicken erythrocytes, which may be related to their lacking the cdb3 binding site. These findings are fully consistent with a molecular mechanism where the oxygen-linked transition of hemoglobin (T-->R) could play a key role in the regulation of anion exchanger activity. 相似文献
132.
Leucci E De Falco G Onnis A Cerino G Cocco M Luzzi A Crupi D Tigli C Bellan C Tosi P Leoncini L Giordano A 《Journal of cellular physiology》2007,212(2):411-415
The Cdk9/Cyclin T1 complex is very important in controlling specific differentiative pathways of several cell types, including muscle cells and neurons. We recently demonstrated the involvement of this complex in B cell activation/differentiation. To check whether the Cdk9/Cyclin T1 complex is also involved in the T cell activation/differentiation process, we isolated different T cell populations by magnetic separation, based on their surface antigens. We observed that the expression level of Cdk9/Cyclin T1 increases in effector T cells (CD27(+)), as well as in activated T cells (CD25(+)) and memory T cells (CD45RA(-)), thus suggesting a specific upregulation of the Cdk9/Cyclin T1 complex following antigen encounter. We have previously demonstrated that in B cells, Cdk9 interacts in vivo with the E2A gene products E12/E47 (members of the basic helix-loop-helix family) which are involved in differentiation. In this article, we show that this interaction also occurs in T cells. This suggests an active role for the Cdk9/Cyclin T1 complex during lymphoid differentiation, through physical binding with E12 and E47. These preliminary results suggest that the Cdk9/Cyclin T1 complex may be important in the activation and differentiation program of lymphoid cells and that its upregulation, which is due to still unknown mechanisms, may contribute to malignant transformation. 相似文献
133.
134.
PDZ Domain in the Engineering and Production of a Saporin Chimeric Toxin as a Tool for targeting Cancer Cells 下载免费PDF全文
135.
Many behaviourally relevant sensory events such as motion stimuli and speech have an intrinsic spatio-temporal structure. This will engage intentional and most likely unintentional (automatic) prediction mechanisms enhancing the perception of upcoming stimuli in the event stream. Here we sought to probe the anticipatory processes that are automatically driven by rhythmic input streams in terms of their spatial and temporal components. To this end, we employed an apparent visual motion paradigm testing the effects of pre-target motion on lateralized visual target discrimination. The motion stimuli either moved towards or away from peripheral target positions (valid vs. invalid spatial motion cueing) at a rhythmic or arrhythmic pace (valid vs. invalid temporal motion cueing). Crucially, we emphasized automatic motion-induced anticipatory processes by rendering the motion stimuli non-predictive of upcoming target position (by design) and task-irrelevant (by instruction), and by creating instead endogenous (orthogonal) expectations using symbolic cueing. Our data revealed that the apparent motion cues automatically engaged both spatial and temporal anticipatory processes, but that these processes were dissociated. We further found evidence for lateralisation of anticipatory temporal but not spatial processes. This indicates that distinct mechanisms may drive automatic spatial and temporal extrapolation of upcoming events from rhythmic event streams. This contrasts with previous findings that instead suggest an interaction between spatial and temporal attention processes when endogenously driven. Our results further highlight the need for isolating intentional from unintentional processes for better understanding the various anticipatory mechanisms engaged in processing behaviourally relevant stimuli with predictable spatio-temporal structure such as motion and speech. 相似文献
136.
Leslie CP Di Fabio R Bonetti F Borriello M Braggio S Dal Forno G Donati D Falchi A Ghirlanda D Giovannini R Pavone F Pecunioso A Pentassuglia G Pizzi DA Rumboldt G Stasi L 《Bioorganic & medicinal chemistry letters》2007,17(4):1043-1046
The synthesis of a series of carbazole derivatives and their SAR at the NPY Y1 receptor is described. Modulation of physicochemical properties by appropriate decoration led to the identification of a high-affinity NPY Y1 antagonist that shows high brain penetration and modest oral bioavailability. 相似文献
137.
Roviello GN Musumeci D Moccia M Castiglione M Sapio R Valente M Bucci EM Perretta G Pedone C 《Nucleosides, nucleotides & nucleic acids》2007,26(10-12):1307-1310
In continuing our research efforts for developing new oligodeoxynucleotide (ODN)-like drugs and diagnostics, we designed diaminobutyric peptide nucleic acids (dabPNAs), nucleopeptides characterized by a diaminobutyric-based building block that is an isomer of the aminoethylglycyl PNA (aegPNA) unit and the acyclic modification of the aminoprolyl PNA (ampPNA) monomer. In this work we present the solid phase synthesis of a dabPNA oligomer and of two aegPNAs containing a single dabPNA unit. A study relative to their binding ability towards DNA is also reported even in comparison with the well known aegPNAs. 相似文献
138.
139.
G Calabrese A Bueti G Zega A Giombolini G Bellomo M A Antonella M Massi-Benedetti P Brunetti 《Hormones et métabolisme》1982,14(10):505-507
It is well known that the glycemic control accomplished by the artificial endocrine pancreas (Biostator; GCIIS), requires an excessive insulin consumption. In order to improve the Biostator performance, we have studied 5 insulin dependent diabetic patients on anticipated automatic pre-programmed insulin infusion starting at the beginning of breakfast. Such an operating method allowed us to obtain a significant reduction in insulin requirements (from 17,3 +/- 2,2 U to 13,3 +/- 2,2 U), and a better glycemic control (MBG 98,7 +/- 5,4 vs 111,1 +/- 5,6; M 2,34 +/- 0,9 vs 6,96 +/- 1,7; delta G 43,8 +/- 3 vs 73,4 +/- 9,7), as compared to those observed under conventional feed-back control in relation to breakfast. 相似文献
140.
Domenica Taruscio Giovanna Floridia Grigor K. Zoraqi Alberto Mantovani Vincenzo Falbo 《Mammalian genome》2002,13(4):216-222
The present paper reports the characterization of HERV-E endogenous retroviral sequences in the human genome by using three
complementary approaches. Firstly, we identified genomic clones containing HERV-E by BLAST screening of human DNA databases
by using the entire sequence of a characterized HERV-E clone (M10976) as a query. The genomic structure and integration sites
of the HERV-E elements were characterized. Secondly, new integration sites of HERV-E elements were revealed by a retroviral
LTR-arbitrary primer-PCR (RELAP-PCR) technique. BLAST analysis of the PCR products identified a subgroup that shows low identity
(75%) to the original clone M10976 and slightly higher identity (80%) to a closely related HERV-E (Ac. n. K02166). Finally,
we performed FISH mapping, which revealed sites of integration of HERV-E not previously identified at the cytogenetic level.
A preliminary analysis of genes mapping in the same bands as HERV-E integration sites was performed: several loci relevant
to physiological and/or pathological processes were detected. Our findings may provide clues to identify HERV-E integration
sites adjacent to genes with important biological roles. 相似文献