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951.
Erik Goormaghtigh Mireille Van Campenhoud Jean-Marie Ruysschaert 《Biochemical and biophysical research communications》1981,101(4):1410-1418
Multilamellar liposomes made of equimolar mixtures of dimyristoyl and distearoylphosphatidylcholine were hydrolysed by porcine pancreatic phospholipase A2. Ph-stat titration, equilibrium gel filtration and differential scanning calorimetry were used to study respectively the enzymic hydrolysis, the enzyme binding and the lipid phase repartition. We demonstrated that the optimal enzyme activity observed in the region where liquid crystalline and gel lipid phases coexist, is due to a drastic increase of the enzyme binding to its substrate. It is suggested that the border region separating the lipid phases could be a privileged site for enzyme insertion. Increase of lateral compressibility due to coexistence of solid and fluid lipid phases will promote the penetration of the hydrophobic interface recognition site (IRS) of phospholipase A2 into the lipid matrix whereas the active site, distinct from the IRS will attack its substrate independently of the lipid physical state. 相似文献
952.
Evidence for the Association of 2',3'-Cyclic-Nucleotide 3'-Phosphodiesterase with Myelin-Related Membranes in Peripheral Nervous System 总被引:3,自引:3,他引:0
Jean-Marie Matthieu Elvira Costantino-Ceccarini Michèle Bény Jacqueline Reigner 《Journal of neurochemistry》1980,35(6):1345-1350
Abstract: In PNS, the specific activity of 2′,3′-cyclic nucleotide 3′-phospho–diesterase (CNP) in myelin was not enriched over the starting homogenate. Nevertheless, most of the total activity was recovered in myelin. In myelin-deficient mutants, low CNP activities were measured in sciatic nerves. CNP specific activities were similar in myelinated and non-myelinated nerves but in non-nervous tissues, they were significantly lower than in nervous tissue. There was no indication for the presence of an isoenzyme of CNP in peripheral nerves. These results indicate that CNP is present in PNS myelin and preferentially localized in Schwann cell plasma membranes. 相似文献
953.
No?mi Eggenberger Basil C. Preisig Rahel Schumacher Simone Hopfner Tim Vanbellingen Thomas Nyffeler Klemens Gutbrod Jean-Marie Annoni Stephan Bohlhalter Dario Cazzoli René M. Müri 《PloS one》2016,11(1)
Background
Co-speech gestures are omnipresent and a crucial element of human interaction by facilitating language comprehension. However, it is unclear whether gestures also support language comprehension in aphasic patients. Using visual exploration behavior analysis, the present study aimed to investigate the influence of congruence between speech and co-speech gestures on comprehension in terms of accuracy in a decision task.Method
Twenty aphasic patients and 30 healthy controls watched videos in which speech was either combined with meaningless (baseline condition), congruent, or incongruent gestures. Comprehension was assessed with a decision task, while remote eye-tracking allowed analysis of visual exploration.Results
In aphasic patients, the incongruent condition resulted in a significant decrease of accuracy, while the congruent condition led to a significant increase in accuracy compared to baseline accuracy. In the control group, the incongruent condition resulted in a decrease in accuracy, while the congruent condition did not significantly increase the accuracy. Visual exploration analysis showed that patients fixated significantly less on the face and tended to fixate more on the gesturing hands compared to controls.Conclusion
Co-speech gestures play an important role for aphasic patients as they modulate comprehension. Incongruent gestures evoke significant interference and deteriorate patients’ comprehension. In contrast, congruent gestures enhance comprehension in aphasic patients, which might be valuable for clinical and therapeutic purposes. 相似文献954.
Libia Alejandra García-Flores Sonia Medina Roberto Cejuela José Miguel Martínez-Sanz Camille Oger Jean-Marie Galano 《Free radical research》2016,50(5):485-494
This randomized and controlled trial investigated whether the increase in elite training at different altitudes altered the oxidative stress biomarkers of the nervous system. This is the first study to investigate four F4-neuroprostanes (F4-NeuroPs) and four F2-dihomo-isoprostanes (F2-dihomo-IsoPs) quantified in 24-h urine. The quantification was carried out by ultra high pressure liquid chromatography-triple quadrupole-tandem mass spectrometry (UHPLC-QqQ-MS/MS). Sixteen elite triathletes agreed to participate in the project. They were randomized in two groups, a group submitted to altitude training (AT, n?=?8) and a group submitted to sea level training (SLT) (n?=?8), with a control group (Cg) of non-athletes (n?=?8). After the experimental period, the AT group triathletes gave significant data: 17-epi-17-F2t-dihomo-IsoP (from 5.2?±?1.4?μg/mL 24?h?1 to 6.6?±?0.6?μg/mL 24?h?1), ent-7(RS)-7-F2t-dihomo-IsoP (from 6.6?±?1.7?μg/mL 24?h?1 to 8.6?±?0.9?μg/mL 24?h?1), and ent-7-epi-7-F2t-dihomo-IsoP (from 8.4?±?2.2?μg/mL 24?h?1 to 11.3?±?1.8?μg/mL 24?h?1) increased, while, of the neuronal degeneration-related compounds, only 10-epi-10-F4t-NeuroP (8.4?±?1.7?μg/mL 24?h?1) and 10-F4t-NeuroP (5.2?±?2.9?μg/mL 24?h?1) were detected in this group. For the Cg and SLT groups, no significant changes had occurred at the end of the two-week experimental period. Therefore, and as the main conclusion, the training at moderate altitude increased the F4-NeuroPs- and F2-dihomo-isoPs-related oxidative damage of the central nervous system compared to similar training at sea level. 相似文献
955.
Marie Umber Jean-Philippe Pichaut Benoît Farinas Nathalie Laboureau Bérenger Janzac Kaïssa Plaisir-Pineau Gersende Pressat Franc-Christophe Baurens Matthieu Chabannes Pierre-Olivier Duroy Chantal Guiougou Jean-Marie Delos Christophe Jenny Marie-Line Iskra-Caruana Frédéric Salmon Pierre-Yves Teycheney 《Molecular breeding : new strategies in plant improvement》2016,36(6):74
Breeding new interspecific banana hybrid varieties relies on the use of Musa acuminata and M. balbisiana parents. Unfortunately, infectious alleles of endogenous Banana streak virus (eBSV) sequences are present in the genome of Musa balbisiana genitors. Upon activation by biotic and abiotic stresses, these infectious eBSVs lead to spontaneous infections by several species of Banana streak virus in interspecific hybrids harboring both Musa acuminata and M. balbisiana genomes. Here we provide evidence that seedy M. balbisiana diploids display diverse eBSV allelic combinations and that some eBSVs differ structurally from those previously reported. We also show that segregation of infectious and non-infectious eBSV alleles can be achieved in seedy M. balbisiana diploids through self-pollination or chromosome doubling of haploid lines. We report on the successful breeding of M. balbisiana diploid genitors devoid of all infectious eBSV alleles following self-pollination and on the potential of breeding additional M. balbisiana diploid genitors free of infectious eBSVs by crossing parents displaying complementary eBSV patterns. Our work paves the way to the safe use of M. balbisiana genitors for breeding banana interspecific hybrid varieties with no risk of activation of infectious eBSVs. 相似文献
956.
Céline Aznar-Derunes Claude Manigand Philippe Picard Alain Dautant Michael Goetz Jean-Marie Schmitter Gilles Precigoux 《Journal of peptide science》2002,8(7):365-372
The yeast Saccharomyces cerevisiae F1F0-ATPase epsilon-subunit (61 residues) was synthesized by the solid-phase peptide approach under both acidic and basic strategies. Only the latter strategy allowed us to obtain a pure epsilon-subunit. The strong propensity of the protein to produce few soluble dimeric species depending on pH has been proved by size-exclusion chromatography, electrophoresis and mass spectrometry. A circular dichroism study showed that an aqueous solution containing 30% trifluoroethanol or 200 mM sodium dodecyl sulphate is required for helical folding. In both solvents at acidic pH, the epsilon-subunit is soluble and monomeric. 相似文献
957.
958.
Evidence of temporal postdischarge decontamination of bacteria by gliding electric discharges: application to Hafnia alvei 总被引:1,自引:0,他引:1
Kamgang-Youbi G Herry JM Bellon-Fontaine MN Brisset JL Doubla A Naïtali M 《Applied and environmental microbiology》2007,73(15):4791-4796
This study aimed to characterize the bacterium-destroying properties of a gliding arc plasma device during electric discharges and also under temporal postdischarge conditions (i.e., when the discharge was switched off). This phenomenon was reported for the first time in the literature in the case of the plasma destruction of microorganisms. When cells of a model bacterium, Hafnia alvei, were exposed to electric discharges, followed or not followed by temporal postdischarges, the survival curves exhibited a shoulder and then log-linear decay. These destruction kinetics were modeled using GinaFiT, a freeware tool to assess microbial survival curves, and adjustment parameters were determined. The efficiency of postdischarge treatments was clearly affected by the discharge time (t*); both the shoulder length and the inactivation rate k(max) were linearly modified as a function of t*. Nevertheless, all conditions tested (t* ranging from 2 to 5 min) made it possible to achieve an abatement of at least 7 decimal logarithm units. Postdischarge treatment was also efficient against bacteria not subjected to direct discharge, and the disinfecting properties of "plasma-activated water" were dependent on the treatment time for the solution. Water treated with plasma for 2 min achieved a 3.7-decimal-logarithm-unit reduction in 20 min after application to cells, and abatement greater than 7 decimal logarithm units resulted from the same contact time with water activated with plasma for 10 min. These disinfecting properties were maintained during storage of activated water for 30 min. After that, they declined as the storage time increased. 相似文献
959.
The ability to adjust reproductive output to environmental conditions is important to the fitness of a species. The semelparous, chordate, Oikopleura dioica, is particularly adept in producing a highly variable number of oocytes in its short life cycle. Here we show that this entails an original reproductive strategy in which the entire female germline is contained in a single multinucleate cell, the "coenocyst". After an initial phase of syncytial nuclear proliferation half of the nuclei entered meiosis whereas the other half became highly polyploid. The inner F-actin network, with associated plasma membranes, formed a highly ramified infrastructure in which each meiotic nucleus was contained in a pseudo-compartmentalized pro-oocyte linked to the common cytoplasm via ring canals. At a set developmental time, a subset of the pro-oocytes was selected for synchronous growth and the common coenocyst cytoplasm was equally partitioned by transfer through the ring canals. Examination of related species indicated that the coenocyst arrangement is a conserved feature of Appendicularian oogenesis allowing efficient numerical adjustment of oocyte production. As Appendicularia are the second most abundant class of zooplankton, with a world-wide distribution, the coenocyst is clearly a common and successful reproductive strategy on a global scale. 相似文献
960.
Krisko A Stjepanović G Pifat G Ruysschaert JM Goormaghtigh E 《Biochimica et biophysica acta》2007,1768(11):2923-2930
Conformational changes of human plasma apolipoprotein B100 (apoB) during oxidative modification of low-density lipoproteins (LDL) have been investigated. Emphasis has been put on the early stages of LDL oxidation and the modification of apoB. We have applied two different modes of LDL oxidation initiation in order to approach the problem from different perspectives. To study conformational changes of the protein and the phospholipids surface monolayer, we have applied attenuated total reflection infrared as well as fluorescence spectroscopy. We have found for the first time that conformational changes of apoB occur even in the earliest stages of oxidation process and that those are located predominantly in the beta-sheet regions. The dynamics of changes has also been described and related to different stages of oxidation. After initial increase in particle surface accessibility and mobility, by entering into the propagation phase of oxidation process, LDL surface accessibility and mobility are decreased. Finally, in the decomposition phase of LDL oxidation, as the particle faces large chemical and physical changes, surface mobility and accessibility is increased again. These observations provide new insights into the modifications of LDL particles upon oxidation. 相似文献