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Temporary pools are numerous in coastal plains of Atlantic Morocco and have a rich and diverse flora. These habitats are increasingly
under pressure by man impact through grazing by domestic livestock and the development of annual crops in their catchments.
The objectives of this work were to evaluate the species richness and the species composition of the vegetation of a sample
of 30 pools in this region, in order to assess the structure of the vegetation within pools and to evaluate the role of environmental
and anthropogenic factors in their richness and species composition. The results highlighted the species richness of the pools
with 300 species found among which annual species were heavily dominant. The structure of the vegetation varied within pools
according to a topographical/flooding gradient and between pools in relation with the land use in the surrounding areas. Three
vegetation belts were recognized from the centre to the periphery of the pool. The total species richness per pool was not
found significantly related to environmental or anthropogenic factors. The species characteristics of the pools were found
mostly in the centre and their number affected by hydrological factors and land use in the pool and in the surrounding areas.
The species characteristics of woodland habitats and of agriculture crops were found mostly in the peripheral zone. Temporary
pools maintain specific communities of both aquatic and amphibious species, probably because of the selection induced by water
level variations. The peripheral zone, although often dominated by terrestrial species, is clearly interpreted as part of
the pool. It contains amphibious species highly characteristic of the pool for which the irregular flooding is a key environmental
factor which decreases competition. 相似文献
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Indrajit Chowdhury Saswati Banerjee Adel Driss Wei Xu Sherifeh Mehrabi Ceana Nezhat Neil Sidell Robert N. Taylor Winston E. Thompson 《Journal of cellular physiology》2019,234(5):6298-6312
Endometriosis is a chronic gynecological inflammatory disorder in which immune system dysregulation is thought to play a role in its initiation and progression. Due to altered sex steroid receptor concentrations and other signaling defects, eutopic endometriotic tissues have an attenuated response to progesterone. This progesterone-resistance contributes to lesion survival, proliferation, pain, and infertility. The current agency-approved hormonal therapies, including synthetic progestins, GnRH agonists, and danazol are often of limited efficacy and counterproductive to fertility and cause systemic side effects due to suppression of endogenous steroid hormone levels. In the current study, we examined the effects of curcumin (CUR, diferuloylmethane), which has long been used as an anti-inflammatory folk medicine in Asian countries for this condition. The basal levels of proinflammatory and proangiogenic chemokines and cytokines expression were higher in primary cultures of stromal cells derived from eutopic endometrium of endometriosis (EESC) subjects compared with normal endometrial stromal cells (NESC). The treatment of EESC and NESC with CUR significantly and dose-dependently reduced chemokine and cytokine secretion over the time course. Notably, CUR treatment significantly decreased phosphorylation of the IKKα/β, NF-κB, STAT3, and JNK signaling pathways under these experimental conditions. Taken together, our findings suggest that CUR has therapeutic potential to abrogate aberrant activation of chemokines and cytokines, and IKKα/β, NF-κB, STAT3, and JNK signaling pathways to reduce inflammation associated with endometriosis. 相似文献
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Hamdi Jaafar Majdi Rouis Laure Coudrat Thierry Gélat Timothy David Noakes Tarak Driss 《PloS one》2015,10(8)
The aim of this study was to examine the impact of emotional eliciting pictures on neuromuscular performance during repetitive supramaximal cycling exercises (RSE). In a randomized order, twelve male participants were asked to perform five 6-s cycle sprints (interspaced by 24 s of recovery) on a cycle ergometer in front of neutral, pleasant or unpleasant pictures. During each RSE, mean power output (MPO) and electromyographic activity [root mean square (RMS) and median frequency (MF)] of the vastus lateralis and vastus medialis muscles were analyzed. Neuromuscular efficiency (NME) was calculated as the ratio of MPO to RMS. Higher RMS (232.17 ± 1.17 vs. 201.90 ± 0.47 μV) and MF (68.56 ± 1.78 vs. 64.18 ± 2.17 Hz) were obtained in pleasant compared to unpleasant conditions (p < 0.05). This emotional effect persisted from the first to the last sprint. Higher MPO was obtained in pleasant than in unpleasant conditions (690.65 ± 38.23 vs. 656.73 ± 35.95 W, p < 0.05). However, this emotional effect on MPO was observed only for the two first sprints. NME decreased from the third sprint (p < 0.05), which indicated the occurrence of peripheral fatigue after the two first sprints. These results suggested that, compared with unpleasant pictures, pleasant ones increased the neuromuscular performance during RSE. Moreover, the disappearance of the beneficial effect of pleasant emotion on mechanical output from the third sprint appears to be due to peripheral fatigue. 相似文献
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Driss Mountassif ;Tarik Baibai ;Latifa Fourrat ;Adnane Moutaouakkil ;Abdelghani Iddar ;M'Hammed Said El Kebbaj ;Abdelaziz S oukri 《Acta biochimica et biophysica Sinica》2009,(5):399-406
A new procedure utilizing immunoaffinity column chromatography has been used for the purification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) from human erythrocytes. The comparison between this rapid method (one step) and the tra- ditional procedure including ammonium sulfate fractionation followed by Blue Sepharose CL-6B chromatography shows that the new method gives a highest specific activity with a highest yield in a short time. The characterization of the purified GAPDH reveals that the native enzyme is a homotetramer of -150 kDa with an absolute specificity for the oxidized form of nicotinamide adenine dinucleotide (NAD+). Western blot analysis using purified monospecific polyclonal antibodies raised against the purified GAPDH showed a single 36 kDa band corresponding to the enzyme subunit. Studies on the effect of temperature and pH on enzyme activity revealed optimal values of about 43℃ and 8.5, respectively. The kinetic parameters were also calculated: the Vmax was 4.3 U/mg and the Km values against G3P and NAD+ were 20.7 and 17.8 μM, respectively. The new protocol described represents a simple, economic, and reproducible tool for the purification of GAPDH and can be used for other proteins. 相似文献
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Neutrophils are essential for host defense and their programmed cell death and removal are critical for the optimal expression as well as for efficient resolution of inflammation. Delayed neutrophil apoptosis or impaired clearance of apoptotic neutrophils by macrophages contributes to the progression of chronic inflammation. Under most conditions, neutrophils are exposed to multiple factors and their fate would ultimately depend on the balance between pro‐survival and pro‐apoptotic signals. Life or death decisions are tightly controlled by a complex network of intracellular signaling pathways. Accumulating data indicate that receptors, such as the formyl peptide receptor 2/lipoxin receptor or β2‐integrins can generate contrasting cues in neutrophils in a ligand‐specific manner and suggest a hierarchy among these signals. In this article, we review recent advances on how pro‐apoptosis and pro‐survival signals interact to determine the fate of neutrophils and the inflammatory response, and highlight novel pharmacological strategies that could be used to enhance the resolution of inflammation by redirecting neutrophils to apoptosis. J. Cell. Biochem. 108: 1039–1046, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Yassine Souidi Najma Boudebouch Sayeh Ezikouri Driss Belghyti Jean‐Franois Trape M'hammed Sarih 《Journal of vector ecology》2014,39(2):316-320
Tick‐borne relapsing fever (TBRF) is caused by Borrelia spirochetes transmitted to humans by Argasid soft ticks of the genus Ornithodoros. We investigated the presence of Ornithodoros ticks in rodent burrows in nine sites of the Gharb region of northwestern Morocco where we recently documented a high incidence of TBRF in humans. We assessed the Borrelia infection rate by nested PCR and sequencing. All sites investigated were colonized by ticks of the Ornithodoros marocanus complex and a high proportion of burrows (38.4%) were found to be infested. Borrelia infections were observed in 6.8% of the ticks tested. Two Borrelia species were identified by sequencing: B. hispanica and B. crocidurae. The discovery in northwestern Morocco of Ornithodoros ticks infected by B. crocidurae represents a 350 km range extension of this Sahelo‐Saharan spirochete in North Africa. The spread of B. crocidurae may be related to the increasing aridity of northwestern Morocco in relation to climate change. 相似文献
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Very High Surface Capacity Observed Using Si Negative Electrodes Embedded in Copper Foam as 3D Current Collectors 下载免费PDF全文
Driss Mazouzi David Reyter Magali Gauthier Philippe Moreau Dominique Guyomard Lionel Roué Bernard Lestriez 《Liver Transplantation》2014,4(8)
Cu foam is evaluated as a replacement for metal foil current collectors to create 3D composite electrodes with the objective to produce Si‐based anodes with high loadings. The electrodes are prepared by casting the slurry into the porosity of the foam. With such a design, the loading and the surface capacity can reach values as high as 10 mg cm?2 and 10 mAh cm?2. Compared to the common 2D design, the 3D copper framework shows a great advantage in the cycle life (more than 400 cycles at a Si loading of 10 mg cm?2 with commercial micrometric particles) and power performance. The thinness of the composite coating on the foam walls favors a better preservation of the electronic wiring upon cycling and fast lithium ion diffusion. A higher coulombic efficiency in half cells with lithium metal as the counter electrode is achieved by using carbon nanofibers (CNF) rather than carbon black (CB). The possibility to reach, in practice, higher surface capacity could allow a significant increase in both the volumetric and gravimetric energy densities by 23% and 19%, respectively, for the Cu foam‐silicon//LiFePO4 stack compared to the graphite/LiFePO4 stack of traditional design. 相似文献
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The one-step synthesis of several β-D/L-arabino- and ribonucleosides was performed in good yields under reflux or microwave-assisted fusion method. A comparison of the two methods showed that better yields were obtained using the reflux conditions. 相似文献