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91.
Interaction of the C-terminal tail region of the metabotropic glutamate receptor 7 with the protein kinase C substrate PICK1 总被引:5,自引:0,他引:5
El Far O Airas J Wischmeyer E Nehring RB Karschin A Betz H 《The European journal of neuroscience》2000,12(12):4215-4221
Group III metabotropic glutamate receptors (mGluRs) are highly enriched in the presynaptic terminals of glutamatergic synapses where they mediate feedback inhibition of neurotransmitter release. Here, we used the yeast two-hybrid system to identify a direct interaction of the C-terminal tail region of mGluR7 with the rat homologue of the protein kinase C substrate PICK1. This interaction is specifically mediated by the very C-terminal amino acids of the receptor and can be reconstituted in human embryonic kidney 293 cells by transfection of full-length mGluR7 and PICK1 cDNAs. Quantitative beta-galactosidase assays revealed that among the different group III mGluRs, mGluR7 is the major PICK1 binding partner although other subfamily members can also interact with PICK1. These data indicate that PDZ domain-containing proteins might contribute to the presynaptic localization of group III mGluRs. 相似文献
92.
93.
Allogeneic stem-cell transplantation may overcome the adverse prognosis of unmutated VH gene in patients with chronic lymphocytic leukemia. 总被引:2,自引:0,他引:2
Carol Moreno Neus Villamor Dolors Colomer Jordi Esteve Rodrigo Martino Josep Nomdedéu Francesc Bosch Armando López-Guillermo Elías Campo Jorge Sierra Emili Montserrat 《Journal of clinical oncology》2005,23(15):3433-3438
PURPOSE: To investigate whether allogeneic stem-cell transplantation (allo-SCT) may overcome the negative impact of unmutated VH genes in the outcome of patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: We analyzed the outcome of patients who underwent SCT according to their VH mutational status. RESULTS: Thirty-four patients (14 allo-SCT and 20 autologous SCT [auto-SCT]) presented unmutated VH genes and 16 patients presented mutated VH genes (nine allo-SCT and seven auto-SCT). Tumoral burden pre-SCT was significantly higher in the allo-SCT patients independent of the VH mutational status. The risk of relapse was significantly higher after auto-SCT (5-year risk, 61%; 95% CI, 44% to 84%) than after allo-SCT (5-year risk 12%, 95% CI, 3% to 44%; P < .05). In the unmutated group, 13 of 20 auto-SCT and two of 14 allo-SCT patients experienced disease progression, with a risk of relapse at 5 years of 66% (95% CI, 48% to 93%) v 17% (95% CI, 5% to 60%), respectively (P = .01). CONCLUSION: These results show that allo-SCT may overcome the unfavorable effect of unmutated VH genes in patients with CLL. 相似文献
94.
G Sconocchia K Keyvanfar F El Ouriaghli M Grube K Rezvani H Fujiwara J P McCoy N Hensel A J Barrett 《Leukemia》2005,19(1):69-76
G-CSF primed CD34 cells cultured for 2-3 weeks in IL-2 and stem cell factor generate CD56(high) cells with phenotypic and morphologic features of NK cells, and a novel adherent CD56(low) CD16- population expressing myeloid markers (CD33 and HLA-DR). We hypothesized that similar cells might also occur in peripheral blood. In 13/13 normal individuals, we found a circulating population of CD56(low), CD33+, FcgammaRI+, FcgammaRII+, HLA-DR+, CD11b(high), CD14+ monocytes closely resembling the cultured CD56(low)CD33+ cells. They may represent a normal counterpart of the CD56+ CD33+ hybrid myeloid/natural killer cell leukemia. Their mean frequency was 1.3+/-1% (standard deviation), range 0.16-3.5%, of total mononuclear cells. CD56(low)CD33+ cells, primed with cytomegalovirus antigen, induced autologous T-lymphocyte proliferation comparably to CD56-, CD14+ peripheral blood monocytes (PBM). Conversely, CD56(low) cells induced greater T-cell proliferation than CD56- PBM when lymphocyte responders were HLA mismatched. Unstimulated CD56(low)CD33+ cells showed a low antiproliferative effect on K562, which was increased upon LPS stimulation. The pattern of cytokine production by CD56(low)CD33+ cells and PBM largely overlapped; however, they produced detectable levels of IL-6 and IL-1beta. These results define a minor monocyte population with distinct phenotypic and functional features. 相似文献
95.
Jamal M. Arif Mohammed Kunhi Yunus M. Siddiqui Khalid A. El Sayed Khaled Y. Orabi Amal Al-Hazzani Mohammed N. Al-Ahdal Fahad M. Al-Khodairy 《Medicinal chemistry research》2004,13(6-7):553-562
In the present study, two of the probable an umor marine compounds, manzamine A and sarcophine, were screened using benzo[a]pyrene (BP)-derived DNA adduct formation in MCF-7 cells as intermediary biomarker. Briefly, MCF-7 cells were treated with
the compounds for 24 h followed by treatment with BP (0.5 μM). After 24h incubation, cellular DNA was isolated and analyzed
for BP-derived DNA adducts by 32P-postlabeling technique. Manzamine A and sarcophine increased the BP-DNA adducts by 2 to 4-folds. Further, manzamine A (50
μM) substantially down regulated the expression of p53 while sarcophine (50 μM) slightly induced the level of p21. The residual
DNA repair ability was almost completely abolished by manzamine A while sarcophine was ineffective. Based on our preliminary
results, these compounds may be classified as potential genotoxic. 相似文献
96.
Christiane Devaux Besma Jouirou Mohamed Naceur Krifi Olivier Clot-Faybesse Mohamed El Ayeb Hervé Rochat 《Toxicon》2004,43(6):661-669
Scorpion stings represent a medical problem in numerous countries. The scorpion Androctonus australis hector produces three alpha toxins (Aah I to III), which are responsible for most of the lethality in mammals. These toxins act on sodium channel and do not cross-react immunologically. We used RIA and ELISA to measure the concentrations of these three toxins in plasma, urine and different organs after i.v. and s.c. injections of water extracts of venoms in rabbits or mice. In both animals, the toxins rapidly appeared in plasma after s.c. injection as it was previously described for the whole venom. However, the toxins disappeared from the blood more quickly than did other main components of the venom. Thus, serotherapy must be initiated immediately to prevent the toxin from reaching its target. We also detected the toxins in urine, kidneys, heart and lungs, but not in the brain. However, the concentration of Aah II was always lower than that of Aah I. Analysis of five samples of venom collected in different areas of southern Tunisia showed that a large polymorphism exists for the three toxins. This is yet another difficulty for serotherapy as there is no cross-antigenicity between them. 相似文献
97.
98.
A. Lahfidi W.M. Traore I.D. Diallo M. Abdellaoui J. El Fenni R. Saouab 《Radiology Case Reports》2022,17(10):3735
The hydatid cyst of the liver is the most common location of hydatid disease. Complications in this form are dominated by superinfection of the cyst and rupture into the bile ducts or the peritoneal cavity. We report the case of a 54-year-old female patient with a hydatid cyst of the liver complicated by a rupture in the gallbladder revealed by urinary symptoms. 相似文献
99.
Abdellah Bouchendouka Zine El Abiddine Fellah Zakaria Larbi Zineeddine Louna Erick Ogam Mohamed Fellah Claude Depollier 《Materials》2022,15(10)
The fully developed laminar flow of a viscous non-Newtonian fluid in a rough-walled pipe is considered. The fluid rheology is described by the power–law model (covering shear thinning, Newtonian, and shear thickening fluids). The rough surface of the pipe is considered to be fractal, and the surface roughness is measured using surface fractal dimensions. The main focus of this study lies in the theoretical investigation of the influence of the pipe surface roughness on the velocity profile and the Darcy friction factor of an incompressible non-Newtonian fluid. The plotted results demonstrate that shear thinning fluids are the most sensitive to the surface roughness compared with Newtonian and shear thickening fluids. For a particular value of the surface fractal dimension, there exists an intersection point where shear thinning, Newtonian, and shear thickening fluids behave the same way regarding the amplitude of the velocity profile and the friction factor. This approach has a variety of potential applications, for instance fluid dynamics in hydrology, blood flow in the cardiovascular system, and many industrial applications. 相似文献
100.