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1.
H. Ben Slimen F. Suchentrunk A. Memmi H. Sert U. Kryger P.C. Alves A. Ben Ammar Elgaaied 《Journal of Zoological Systematics and Evolutionary Research》2006,44(1):88-99
Systematics and taxonomy of hares of the genus Lepus (Lagomorpha) are under contentious debate, and phylogenetic relationships among many taxa are not well understood. Here we study genetic differentiation and evolutionary relationships among North African hares, currently considered subspecies of Lepus capensis , cape hares ( L. capensis ) from the Cape province in South Africa, and brown hares ( L. europeaus ) from Europe and Anatolia, using maternally (mtDNA) and biparentally (allozymes) inherited markers. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of a c. 1.8 kb long segment of the mitochondrial control region using eight hexanucleotide-recognizing restriction endonucleases yielded 28 haplotypes, and horizontal starch gel electrophoresis of proteins encoded by 25 structural gene loci revealed 52 alleles at 18 polymorphic loci. Diverse phylogenetic analyses (neighbor joining dendrogram, median joining network, multidimensional scaling of pairwise distances, AMOVA, F -statistics, hierarchical F -statistics) of genetic variants revealed marked substructuring of mtDNA into three phylogeographic groups, namely an African, a central European, and an Anatolian, but a somewhat less pronounced overall differentiation of the nuclear genome, despite a relatively high number of population-specific (private) alleles. However, all our results are not incongruent with Petter's (1959: Mammalia 23 , 41; 1961: Z. f. Säugetierkunde 26 , 30; 1972 : Société Des Sciences Naturelles et Physiques du Maroc 52 , 122) hypothesis that North African hares generally belong to L. capensis and that brown hares should be included in this species as well. 相似文献
2.
Eya Khemis Mayssa Ben Mustapha Ikbel Chaieb Roberta Ascrizzi Guido Flamini Abdel Halim Harrath Hichem Ben Jannet Afifa Zardi-Bergaoui 《化学与生物多样性》2023,20(2):e202200646
Due to the several side effects of synthetic pesticides, including environmental pollution, threats to human health, and the development of pest resistance to insecticides, the use of alternative healthy, available and efficient agents in pest management strategies is necessary. Recently, the use of essential oil obtained from aromatic plants has shown significant potential for insect pest management. For this reason, the essential oil isolated from seeds of Thapsia garganica L. was investigated for the first time for its chemical profile, and its toxicity and repellency effects against Tribolium castaneum adults. Qualitative and quantitative analyses of the chemical composition by gas chromatography coupled to mass spectrometry (GC/MS) revealed the presence of 18 organic volatiles representing 96.8 % of the total constituents. The main compounds were 1,4-dimethylazulene (51.3 %) followed by methyl palmitate (8.2 %), methyl linoleate (6.2 %) and costol (5.1 %). Concerning the repellent effect, results revealed that SEO (Seed Essential Oil) was very repellent towards T. castaneum adults, with 100 % repellency after 2 h of exposure. Furthermore, the essential oil exhibited remarkable contact toxicity against T. castaneum (93.3 % of mortality) at the concentration of 10 % (v/v). The median lethal dose (LD50) of the topical application of the seed essential oil was 4.4 %. These encouraging outcomes suggested that the essential oil from T. garganica seeds could be considered a potent natural alternative to residual persistent and toxic insecticides. 相似文献
3.
A new caryophyllene, named pulicaryenne A ( 1 ), along with four other known caryophyllene derivatives ( 2 , 3 , 4 and 5 ) were isolated from the ethyl acetate extract of aerial parts of Pulicaria vulgaris Gaertn . (Asteraceae). All compounds were isolated for the first time from this species. Compound 2 was identified as a new epimer of a known caryophyllene derivative isolated previously from P. dysenterica. Their structures were established by spectroscopic means including NMR analysis (1D‐ and 2D‐NMR) and ESI‐TOF‐MS. All compounds were evaluated for their anticholinesterase, antityrosinase and cytotoxic activities against two human cell lines (A549 and HeLa). Results showed that compound 5 exhibited the highest cytotoxic effect against A549 and anticholinesterase activity with IC50 values of 8.50±0.75 and 6.45±0.09 μg/mL, respectively. Furthermore, compound 5 showed also an interesting antityrosinase activity with percent inhibition value of 79.0±2.5 % at 50 μg/mL. The bioactivity and drug likeness scores of the isolated compounds 1–5 were calculated using Molinspiration software and discussed. These results may suggest that the five caryophyllene derivatives endowed with good biological properties, which could be used as bioactive alternatives in pharmaceutical preparations. 相似文献
4.
In East Africa, cape hares (Lepus capensis) and savanna hares (L. victoriae) look much alike where their ranges overlap. Earlier studies suggested discrimination between the two species by several skull traits, but did not present morphometric statisitics. Our present discriminant analysis based on seven metric variables of the occipital bone related to skull length (condylobasal length) resulted in a high (95.1%) overall probability of correct separation of the two species. While all cape hares were classified correctly, correct classification was a bit lower in savanna hares (88.2%). A principal components analysis of the same variables confirmed the shape difference for the two species. Both region and sex-specific variation in the shape of the studied occipital bone complex was found in savanna hares but not in cape hares. The somewhat reduced level of correct identification of savanna hares might be due to a tendency for higher shape variation. Application of our discriminant analysis to other regions in East Africa is discussed. 相似文献
5.
Asma El Ayeb‐Zakhama Lamia Sakka‐Rouis Afifa Bergaoui Guido Flamini Hichem Ben Jannet Fethia Harzallah‐Skhiri 《化学与生物多样性》2015,12(4):615-626
Acacia cyanophylla Lindl . (Fabaceae), synonym Acacia saligna (Labill .) H. L.Wendl ., native to West Australia and naturalized in North Africa and South Europe, was introduced in Tunisia for rangeland rehabilitation, particularly in the semiarid zones. In addition, this evergreen tree represents a potential forage resource, particularly during periods of drought. A. cyanophylla is abundant in Tunisia and some other Mediterranean countries. The chemical composition of the essential oils obtained by hydrodistillation from different plant parts, viz., roots, stems, phyllodes, flowers, and pods (fully mature fruits without seeds), was characterized for the first time here. According to GC‐FID and GC/MS analyses, the principal compound in the phyllode and flower oils was dodecanoic acid ( 4 ), representing 22.8 and 66.5% of the total oil, respectively. Phenylethyl salicylate ( 8 ; 34.9%), heptyl valerate ( 3 ; 17.3%), and nonadecane (36%) were the main compounds in the root, stem, and pod oils, respectively. The phyllode and flower oils were very similar, containing almost the same compounds. Nevertheless, the phyllode oil differed from the flower oil for its higher contents of hexahydrofarnesyl acetone ( 6 ), linalool ( 1 ), pentadecanal, α‐terpineol, and benzyl benzoate ( 5 ) and its lower content of 4 . Principal component and hierarchical cluster analyses separated the five essential oils into four groups, each characterized by its main constituents. Furthermore, the allelopathic activity of each oil was evaluated using lettuce (Lactuca sativa L.) as a plant model. The phyllode, flower, and pod oils exhibited a strong allelopathic activity against lettuce. 相似文献
6.
Nassira Zribi Nozha Feki Chakroun Fatma Ben Abdallah Henda Elleuch Afifa Sellami Jalel Gargouri Tarek Rebai Faiza Fakhfakh Leila Ammar Keskes 《Cryobiology》2012
We aimed in the first part of our work to study the effect of cryopreservation on the human sperm DNA integrity and the activation of caspase 3, the main apoptosis indicator. In the second part, we were interested in testing the effect of quercetin, as an antioxidant, in preventing sperm damage during the freeze–thawing process. Seventeen semen samples were obtained from 17 men recruited for infertility investigations. Liquefied sperm was cryopreserved using spermfreeze®. Nine of the used samples were divided into two aliquots; the first one was cryopreserved with spermfreeze only (control) and the second one was cryopreserved with spermfreeze supplemented with quercetin to a final concentration of 50 μM. Sperm motility and viability were assessed according to WHO criteria. We used TUNEL assay and the Oxy DNA assay to assess sperm DNA integrity. Activated caspase 3 levels were measured in spermatozoa using fluorescein-labeled inhibitor of caspase (FLICA). Cryopreservation led to a significant increase in sperm DNA fragmentation, DNA oxidation and caspase 3 activation (p < 0.01). Supplementation of the cryopreservation medium with quercetrin induced a significant improvement in post thaw sperm parameters, compared to those of control, regarding sperm motility (p = 0.007), viability (p = 0.008) and DNA integrity (p = 0.02); however, it had no effect on caspase 3 activation (p = 0.3). We conclude that oxidative stress plays a major role in inducing sperm cryodamage but implication of apoptosis in this impairment requires further investigations. Quercetin could have protective effect during cryopreservation but further research is needed to confirm this effect. 相似文献
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8.
Asma Awadi Hichem Ben Slimen Steve Smith Jonas Kahlen Mohamed Makni Franz Suchentrunk 《Comptes rendus biologies》2018,341(6):315-324
Toll-like receptors (TLRs) are a major group of proteins that recognize molecular components of infectious agents, known as pathogen associated molecular patterns (PAMPs). The structure of these genes is similar and characterized by the presence of an ectodomain, a signal transmembrane segment and a highly conserved cytoplasmic domain. The latter domain is homologous to the human interleukin-1 receptor (IL1R) and human IL-18 receptor (IL-18R) and designated TIR domain. The latter domain of the TLR genes was suggested to be very conservative and its evolution is driven by purifying selection. Variability and evolution of the TIR sequences of TLR2 gene were studied in three hare populations from Tunisia with different ecological characteristics (NT–North Tunisia with Mediterranean, CT–Central Tunisia with semi-arid, and ST–South Tunisia with arid climate). Sequencing of a 372 bp fragment of TIR2 revealed 25 alleles among 110 hares. Twenty variable nucleotide positions were detected, of which 7 were non-synonymous. The highest variability was observed in CT, with 16 polymorphic positions. In ST, only 4 polymorphic nucleotide positions were detected with all diversity values lower than those recorded for the other two populations. By using several approaches, no positive selection was detected. However, evidence of purifying selection was found at two positions. The logistic models of the most common TIR2 protein variant that we run to examine whether its occurrence was affected by climatic variation independent of the geographic sample location suggested only a longitudinal effect. Finally, the mapping of the non-synonymous mutations to the inferred tertiary protein structure showed that they were all localized in the different loop regions. Among all non-synonymous substitutions, three were suggested to be deleterious as evidenced by PROVEAN analysis. The observed patterns of variability characterized by low genetic diversity in ST might suggest that the TIR region was more affected, than other markers, by genetic drift or/and that these patterns were shaped by different selective pressures under different ecological conditions. Notably, this low diversity was not detected by other (putatively neutral) microsatellite markers analysed in the course of other studies. But low diversity was also found for two MHC class II adaptive immune genes. As expected from functionally important regions, the evolution of the TIR2 domain is mainly driven by purifying selection. However, the occurrence of deleterious non-synonymous substitutions might highlight the flexible evolution of the TIR genes and/or their interactions with other proteins. 相似文献
9.
Chemical Composition and Biological Studies of the Essential Oil from Aerial Parts of Beta vulgaris subsp. maritima (L.) Arcang. Growing in Tunisia
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Afifa Zardi‐Bergaoui Aymen Ben Nejma Fethia Harzallah‐Skhiri Guido Flamini Roberta Ascrizzi Hichem Ben Jannet 《化学与生物多样性》2017,14(10)
The chemical composition, antioxidant, cytotoxic, anticholinesterase and anti‐tyrosinase activities of the hydrodistilled essential oil of the aerial parts of Beta vulgaris subsp. maritime (L.) Arcang . from Tunisia have been evaluated. The chemical composition of the oil (yield 0.037% [w/w]), determined by GC‐FID and GC/MS is reported for the first time. Twenty five components, accounting for 98.1% of the total oil have been identified. The oil was characterized by a high proportion of oxygenated sesquiterpenes (39.2%), followed by sesquiterpene hydrocarbons (30.3%) and one apocarotenoids (26.3%). The main compounds were γ‐irone (26.3%), α‐cadinol (12.1%), T‐cadinol (10.6%), bicyclogermacrene (10.4%) and δ‐cadinene (6.0%). The isolated oil was tested for its antioxidant activity using the DPPH·, ABTS+·, catalase, and paraoxonase assays and also for its cytotoxic, anticholinesterase, and anti‐tyrosinase activities. The essential oil exhibited high antioxidant activity (IC50 = 0.055 ± 0.006 mg/ml) and important result oncatalase (524.447 ± 2.58 Units/mg protein). Furthermore, it exerted a significant cytotoxic effect against A549 cell line, with IC50 = 42.44 ± 1.40 μg/ml. The results indicate that the essential oil of B. vulgaris subsp. maritima (L.) Arcang . aerial parts may be used in future as an alternative to synthetic antioxidant agents, with potential application in the food and pharmaceutical industries. 相似文献
10.
Mourad Hadj Slimen Hammadi Fakhfakh Mohamed Gassara Sofiane Kechaou Ali Bahloul Mohamed Nabil Mhiri 《Andrologie》2008,18(4):264-273