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1.
Julien Benoit El Mabrouk Essid Wissem Marzougui Hayet Khayati Ammar Renaud Lebrun Rodolphe Tabuce Laurent Marivaux 《Journal of human evolution》2013
We report the discovery of three isolated primate petrosal fragments from the fossiliferous locality of Chambi (Tunisia), a primate-bearing locality dating from the late early to the early middle Eocene. These fossils display a suite of anatomical characteristics otherwise found only in strepsirhines, and as such might be attributed either to Djebelemur or/and cf. Algeripithecus, the two diminutive stem strepsirhine primates recorded from this locality. Although damaged, the petrosals provide substantial information regarding the ear anatomy of these advanced stem strepsirhines (or pre-tooth-combed primates), notably the patterns of the pathway of the arterial blood supply. Using μCT-scanning techniques and digital segmentation of the structures, we show that the transpromontorial and stapedial branches of the internal carotid artery (ICA) were present (presence of bony tubes), but seemingly too small to supply enough blood to the cranium alone. This suggests that the ICA was not the main cranial blood supply in stem strepsirhines, but that the pharyngeal or vertebral artery primitively ensured a great part of this role instead, an arterial pattern that is reminiscent of modern cheirogaleid, lepilemurid lemuriforms and lorisiforms. This could explain parallel loss of the ICA functionality among these families. Specific measurements made on the cochlea indicate that the small strepsirhine primate(s) from Chambi was (were) highly sensitive to high frequencies and poorly sensitive to low frequencies. Finally, variance from orthogonality of the plane of the semicircular canals (SCs) calculated on one petrosal (CBI-1-569) suggests that Djebelemur or cf. Algeripithecus likely moved (at least its head) in a way similar to that of modern mouse lemurs. 相似文献
2.
Myriam Harrabi Jihène Bettaieb Wissem Ghawar Amine Toumi Amor Zaatour Rihab Yazidi Sana Chaabane Bilel Chalghaf Mallorie Hide Anne-Laure Ba?uls Afif Ben Salah 《PLoS neglected tropical diseases》2015,9(8)
In Tunisia, cases of zoonotic cutaneous leishmaniasis caused by Leishmania major are increasing and spreading from the south-west to new areas in the center. To improve the current knowledge on L. major evolution and population dynamics, we performed multi-locus microsatellite typing of human isolates from Tunisian governorates where the disease is endemic (Gafsa, Kairouan and Sidi Bouzid governorates) and collected during two periods: 1991–1992 and 2008–2012. Analysis (F-statistics and Bayesian model-based approach) of the genotyping results of isolates collected in Sidi Bouzid in 1991–1992 and 2008–2012 shows that, over two decades, in the same area, Leishmania parasites evolved by generating genetically differentiated populations. The genetic patterns of 2008–2012 isolates from the three governorates indicate that L. major populations did not spread gradually from the south to the center of Tunisia, according to a geographical gradient, suggesting that human activities might be the source of the disease expansion. The genotype analysis also suggests previous (Bayesian model-based approach) and current (F-statistics) flows of genotypes between governorates and districts. Human activities as well as reservoir dynamics and the effects of environmental changes could explain how the disease progresses. This study provides new insights into the evolution and spread of L. major in Tunisia that might improve our understanding of the parasite flow between geographically and temporally distinct populations. 相似文献
3.
Mohamed Ben Sghaier Jihed Boubaker Aicha Neffati Ilef Limem Ines Skandrani Wissem Bhouri Ines Bouhlel Soumaya Kilani Leila Chekir‐Ghedira Kamel Ghedira 《化学与生物多样性》2010,7(7):1754-1763
The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4‐nitro‐o‐phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro‐blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical‐scavenging activity was observed towards DPPH. and O$\rm{{_{2}^{{^\cdot} -}}}$ . In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay. 相似文献
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Borago officinalis rosette leaves were sampled in the region of Amdoun (Tunisia) during different stages of their development. Essential oil contents varied from 0.01% to 0.13% respectively in young and adult leaves. Twenty three volatile compounds were identified. Hydrocarbons, mainly represented by nonadecane (29.8%), tetracosane (11.3%) and heptacosane (4.7%), constituted the major class in the young leaves (45.8%), followed by aldehydes (22.4%). The percentages of these two classes decreased to reach respectively 15% and 8.1% in adult leaves in favour of alcohols (57.9%) where cis-3-hexenol (29.6%) and hexanol (14.5%) were the main compounds. Total fatty acids amounts increased from 5.03 mg/g DW in young leaves to 32.23 mg/g DW in adult ones. The predominant fatty acids were alpha-linolenic (C18:3 n-3), stearidonic (C18:4 n-3), gamma-linolenic (C18:3 n-6), palmitic (C16: 0) and linoleic (C18:2 n-6) acids. 相似文献
6.
Mapping and characterization of seed dormancy QTLs using chromosome segment substitution lines in rice 总被引:1,自引:0,他引:1
Marzougui S Sugimoto K Yamanouchi U Shimono M Hoshino T Hori K Kobayashi M Ishiyama K Yano M 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2012,124(5):893-902
Seed dormancy—the temporary failure of a viable seed to germinate under favorable conditions—is a complex characteristic influenced
by many genes and environmental factors. To detect the genetic factors associated with seed dormancy in rice, we conducted
a QTL analysis using chromosome segment substitution lines (CSSLs) derived from a cross between Nona Bokra (strong dormancy)
and Koshihikari (weak dormancy). Comparison of the levels of seed dormancy of the CSSLs and their recurrent parent Koshihikari
revealed that two chromosomal regions—on the short arms of chromosomes 1 and 6—were involved in the variation in seed dormancy.
Further genetic analyses using an F2 population derived from crosses between the CSSLs and Koshihikari confirmed the allelic differences and the chromosomal locations
of three putative QTLs: Sdr6 on chromosome 1 and Sdr9 and Sdr10 on chromosome 6. The Nona Bokra alleles of the three QTLs were associated with decreased germination rate. We discuss the
physiological features of the CSSLs and speculate on the possible mechanisms of dormancy in light of the newly detected QTLs. 相似文献
7.
Sylvain Adnet Medhi Mouana Anne-Lise Charruault El Mebrouk Essid Hayet Khayati Ammar Wissem Marzougui 《Historical Biology》2013,25(9):1213-1222
AbstractHypolophin ‘dasyatids’ are a common group of large stingrays today frequenting the Indo-Pacific inshores. Being often harvested in their restricted area, few are known about their biology and their evolutionary history despite a very peculiar dental pattern making it easy to track their fossil record. An abundant material consisting of isolated teeth from Late Bartonian (38–40 Ma) lagoonal deposits of Djebel el Kébar, Tunisia, allows to describe a new stingray, Pastinachus kebarensis nov. sp. This taxon represents the oldest occurrence for this genus but also the oldest fossil record for hypolophins. A dental comparison of these fossils with 3D rendered models of fresh specimens testifies that early hypolophin representatives had already a strongly arcuate and bulbous upper jaw, interlocking with a broad and elongated tooth plate on the lower jaw. This new fossil and its fossil relatives (here updated), indicate a pre-Bartonian origination for hypolophins in western Neotethys, and reveal a rapid and widespread colonization of the proto-Mediterranean Sea, western Atlantic and Indo-Pacific coasts during the late Paleogene–early Neogene. Finally, it is worth noting that early hypolophin representatives seemingly entered freshwater habitats occasionally as modern cowtail stingrays do. 相似文献
8.
Boubaker J Bhouri W Sghaier MB Bouhlel I Skandrani I Ghedira K Chekir-Ghedira L 《Cancer cell international》2011,11(1):37
Background
In this report the phytochemical profile of Nitraria. Retusa (N. Retusa) leaf extracts were identified and their ability to induce apoptosis in human chronic myelogenous erythroleukaemia (K562) was evaluated.Methods
Apoptosis of the human chronic myelogenous erythroleukaemia (K562) was evidenced by investigating DNA fragmentation, PARP cleavage and caspases 3 and 8 inducing activities, in the presence of N. retusa extracts.Results
Our study revealed that the tested extracts from N. Retusa contain many useful bioactive compounds. They induced in a time-dependent manner the apoptosis the tested cancerous our cell line. This result was confirmed by ladder DNA fragmentation profile and PARP cleavage, as well as a release in caspase-3 and caspase-8 level.Conclusion
Our results indicate that the tested compounds have a significant antiproliferative effect which may be due to their involvement in the induction of the extrinsic apoptosic pathway.9.
Wissem Mnif Ines Zidi Aziza Ibn Hadj Hassine Elena Gomez Aghleb Bartegi Benoit Roig 《Soil & Sediment Contamination》2012,21(7):815-830
Anthropogenic chemicals occurring in the environment, namely endocrine-disrupting chemicals (EDCs), have generated growing concern over their potential adverse effects on human wildlife health and ecosystem processes. This interest resulted particularly from their abilities to mimic the effect of endogenous hormones. In this study, we used stable transfected reporter cell lines to investigate the endocrine-disrupting profile of water as well as sediment samples. Samples are collected from up- and downstream of an industrial wastewater discharge point at the Hamdoun River in the vicinity of an industrial zone located at the center of Tunisia. The analysis of estrogen, androgen, and xenobiotic (pregnane X and dioxin) ligands receptors expressed by chimeric cell lines indicated that while the water and sediment samples from upstream sites have lower levels of estrogenic activity, those from downstream exhibited stronger estrogenic, aryl hydrocarbon receptor (AhR), and Pregnane X Receptor (PXR) activities. Moreover, collected samples have shown hormonal activity in terms of all tested receptors except the androgenic ones. In vitro recombinant estrogen receptor competitive binding assays revealed that while the estrogenic activities of the downstream water sample compounds had a strong affinity for estrogen receptor α (ERα), those present in the sediment samples showed a weaker one. These findings were consolidated by subsequent chemical analysis (high-performance liquid chromatography with UV detectors). Our results indicate that the water and sediment discharges at the Hamdoun River represent a major sink for EDCs from natural and industrial effluents, particularly those of the textile industry, with pernicious potential to disrupt normal endocrine functions. 相似文献
10.
Laurent Marivaux Anusha Ramdarshan El Mabrouk Essid Wissem Marzougui Hayet Khayati Ammar Renaud Lebrun Bernard Marandat Gilles Merzeraud Rodolphe Tabuce Monique Vianey-Liaud 《PloS one》2013,8(12)