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Phylogenetic Relationship and Molecular Divergence Dating Using SRY Gene Polymorphism about Four Ladoum Sheep Lineages in Senegal

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Open Journal of Animal Sciences 2023年第2期13卷 179-198页

作者： Pape Madiop Sembène Fatimata Mbaye Mama Racky Ndiaye Mbacké Sembène Genomic Laboratory Department of Animal Biology Cheikh Anta Diop University Dakar Senegal

Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate the phylogenetic relationships through the evolution of the SRY gene in four different lineages of Ladoum sheep raised in Senegal. After a brief analysis of genetic diversity, the phylogenetic relationships and molecular dating were inferred through haplotype networks and four phylogenetic reconstruction methods. The different haplotype networks are constructed with neTWORK ver. 5.***.0.0 using the Median-Joining method. Phylogenetic trees were reconstructed using neighbor-joining, maximum parsimony, maximum likelihood and Bayesian inference. The robustness of the nodes in phylogenetic trees of the three first methods was assessed by 1000 bootstraps. For Bayesian inference, the posterior probability distribution of the trees was estimated by 4 MCMC chains. 5,000,000 generations were performed for each of the chains by sampling the different parameters every 1000 generations. Results show a low polymorphism. Haplotypic diversity is much higher than the average nucleotide divergence between all pairs of haplotypes. The majority and central haplotype indicates a close relationship between “Batling” and “Tyson” individuals. “Birahim” lineage is very distinct from the rest. Phylogenetic trees confirm two genetically separate clades between “Birahim” and the other lineages. The period of divergence between “Birahim” lineage versus the common ancestor of the other three lineages was 2504 years ago. The polyphyly revealed in “Birahim” lindicates that this lineage does not contain the common ancestor of all individuals who compose it. It could therefore be derived from two or more sheep breeds with a common ancestor, Ovis aries. The monophyletic clade appears to be a group including a common ancestor and all of its genetic descendants. This group, bringing togethe

关键词： Genetic Diversity Phylogenetic Relationship Molecular Dating SRY Gene Sheeps Ladoum Senegal

SPUTTERING BEHAVIOUR OF IRON SILICIDES UNDER LOWEneRGY Ar^+ ION BOMBARDMENT

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0-0页

作者： Z.X. Cao E.G. Wang and YX. ne(State Key Laboratory for Surface Physics, Institute of Physics, Beijing 100080, China)

Surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sample bulk compositions. While in FeSi and FeSi2 only Fe enrichment in the selvage has been observed, in Fe3Si it is Si enriched when the ion enerpy is higher than 31OeV Competition between preferential sputtering and radiation enhanced segmpation is quoted to eoplain this phenomenon.

关键词： preferential sputtering iron silicides radiation enhanced segregation

The Lipid Bilayer of Biological Vesicles: A Liquid-Crystalline Material as Nanovehicles of Information

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Journal of Biomaterials and Nanobiotechnology 2014年第2期5卷 105-115页

作者： Annette Alfsen Irène Tatischeff CNRS & UPMC Honorary Research Director Paris France CNRS Honorary Research Director Paris France

The biological intracellular vesicles, formed from the cell membrane or from different cell organelles, play a main role in the intracellular transport, transfer and exchange of molecules and information. Extracellular vesicles are also detected in organisms belonging to any of the three main branches of evolution, Archaea, Bacteria and Eukarya. There is an increasing consensus that these vesicles are important mediators of intercellular communication. All the intracellular and extracellular vesicles present a characteristic lipid composition and organization that governs their formation, targeting and function. This paper gives an overview of the lipid chemical and physical structure, strongly related to their biological function. The properties and role of the different types of lipids from membranes and vesicles are described. Then, their physical structure is shown as self-associated in a bilayer and organized as a lyotropic liquid crystal. The present paper underlies the structural similarity between these biological vesicles and a new synthetic material, the “liquid crystalline fullerodendrimers” obtained from the biological model. It is composed of a basket of carbon associated with a liquid crystalline material and has been shown to exhibit highly efficient properties of information transfer. Our observation stresses the essential role of the liquid crystalline structure of lipids in their function as biological nanovehicles of information. The comparison with the synthetic material contributes to a better understanding of the role of lipids for cell communication in living organisms.

关键词： Coated Vesicles Extracellular Vesicles Lipid Bilayer Liquid Crystalline Material

A new Biological Strategy for Drug Delivery: Eucaryotic Cell-Derived Nanovesicles

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Journal of Biomaterials and Nanobiotechnology 2011年第5期2卷 494-499页

作者： Irène Tatischeff Annette Alfsen 不详

An efficient drug delivery is the prerequisite of the successful chemotherapeutic treatments of many human diseases. Despite a great number of approaches, the improvement of drug cell internalization remains an actual research challenge. We propose a new biological delivery system based on the extracellular vesicles released by a non-pathological eukaryotic microorganism, Dictyostelium discoideum. After a summary of the main characteristics of these extracellular vesicles, including of their lipid bilayer that appears as a good candidate for initiating membrane fusion, followed by delivery of their encapsulated drug, the capacity of these vesicles to convey drugs into human cells was demonstrated in vitro on two tumor cell lines, resistant leukaemia K562r and cervix carcinoma HeLa cells. A comparison with other extracellular vesicles, like exosomes or bacteria-derived particles, stresses the unique properties of Dictyostelium extracellular nanovesicles for drug delivery.

关键词： Biological Extracellular Vesicles Antitumoral Drug Delivery Dictyostelium discoideum

Osteocyte pericellular and perilacunar matrices as markers of bone-implant mechanical integrity

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BIOCELL 2022年第10期46卷 2209-2216页

作者： ReMY GAUTHIER HeLÈne FOLLET ANA-MARIA TRUNFIO-SFARGHIU DELPHIne FARLAY NINA ATTIK SYLVAIN MEILLE JeRÔME CHEVALIER DAVID MITTON Universite de Lyon CNRSINSA de LyonUniversite Claude Bernard Lyon 1MATEISUMR5510VilleurbanneF-69621France Universite de Lyon Universite Claude Bernard Lyon 1INSERMLYOS UMR 1033LyonF-69008France Universite de Lyon INSA-LyonCNRS UMR5259LaMCoSVilleurbanneF-69621France Universite de Lyon Universite Claude Bernard Lyon 1UMR CNRS 5615Laboratoire des Multimateriaux et InterfacesVilleurbanneF-69622France Universite de Lyon Universite Claude Bernard Lyon 1Faculte d’OdontologieLyonF-69008France Universite de Lyon Universite Gustave EiffelUniv Claude Bernard Lyon 1LBMC UMR_T 9406LyonF-69622France

To develop durable bone healing strategies through improved control of bone repair,it is of critical importance to understand the mechanisms of bone mechanical integrity when in contact with biomaterials and *** mechanical integrity is defined here as the adaptation of structural properties of remodeled bone in regard to an applied mechanical ***,the authors present why future investigations in bone repair and regeneration should emphasize on the matrix surrounding the *** are mechanosensitive cells considered as the orchestrators of bone remodeling,which is the biological process involved in bone *** bone cells are trapped in an interconnected porous network,the lacunocanalicular network,which is embedded in a bone mineralized extracellular *** a consequence of an applied mechanical loading,the bone deformation results in the deformation of this lacunocanalicular network inducing a shift in interstitial fluid pressure and velocity,thus resulting in osteocyte *** material environment surrounding each osteocyte,the so called perilacunar and pericellular matrices properties,define its *** this mechanical stimulation pathway is well known,the laws used to predict bone remodeling are based on strains developing at a tissue scale,suggesting that these strains are related to the shift in fluid pressure and velocity at the lacunocanalicular *** this relationship has been validated through observation in healthy bone,the fluid behavior at the bone-implant interface is more *** presence of the implant modifies fluid behavior,so that for the same strain at a tissue scale,the shift in fluid pressure and velocity will be different than in a healthy bone *** that context,new markers for bone mechanical integrity,considering fluid behavior,have to be *** viewpoint exposed by the authors indicates that the properties of the pericellular and the perilacunar

关键词： Bone mechanical integrity Osteocytes Pericellular Perilacunar Mechanosensitivity

Full Cycle Cold Flow Analysis of the Effect of Twin Swirl Combustion Chamber Design in a Diesel Engine

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World Journal of Mechanics 2016年第4期6卷 109-117页

作者： Doğan Güneş Mehmet Serkan Horasan Mechanical Engineering Department Istanbul Bilgi University Istanbul Turkey

new designs and adaptation methods are experimented to ensure compliance to ever increasing emissions and efficiency requirements of modern diesel engines. Piston head structure which influences the mixing rate and timing of the fuel within in the combustion chamber is known to enable increase in combustion efficiency and thus lower emission rates. In this paper, computation analysis of flow within a diesel engine cylinder with a twin swirl combustion chamber design throughout a full cycle is presented. The results obtained indicate that the effect of the twin swirl combustion chamber on the cold flow conditions is noteworthy and further analysis together with experiments may reveal information that may prove to be useful in further new designs.

关键词： Cold Flow Analysis Combustion Chamber Design Internal Combustion Engine Diesel Engine

Diversity and Genetic Structuration of Populations of <i>Plutella xylostella</i>(Lepidoptera, Plutellidae), Cabbage Farming Destroyer in Senegal

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Advances in Entomology 2022年第1期10卷 1-13页

作者： Toffène Diome Mamecor Faye Marième Seck Cheikh Tidiane Niass Mbacké Sembène Genetic Team and Population Management Department of Animal Biology Faculty of Sciences and Technology Cheikh Anta Diop University Dakar Senegal Laboratory of Parasitology Department of Animal Biology Faculty of Sciences and Technology Cheikh Anta Diop University Dakar Senegal

Plutella xylostella, pointed out as the most dangerous destroyer of cabbage (Brassica olerarea), is a cosmopolitan species. In fact, owing to its large capacity of adaptation, P. xylestella colonizes any kind of area. This insect can bring about up to 90% of losses on cabbage farming. To control the insect, Senegalese farmers, very often, resort to high dose of chemical pesticides which are repetitively sprayed. The use of these chemical products gives rise to different varieties of resistant insects, which results in the emergence of different haplotypes between populations. It is in such a context that this study has been undertaken. Our objective is then to contribute to the knowledge of the genetic diversity of P. xylostella populations in Senegal. To hit the target, PCR- Sequencing method has been applied on samples from the five following localities: Diofior, Malika, Mboro, Santh Ndong, and Sebikotane. P. xylostella from Mboro is genetically different from the other populations. This fact could be due to a different way of using pesticides in this area vis-à-vis of the other localities. On the other hand, between populations of P. xylostella from Diofior, Malika, Santh Ndong, and Sebikotane, there is no significant genetic difference. In other respects, phylogenetic trees reveal the existence of two clades: one with individuals from Mboro and the other one with individuals from the other four localities. P. xylostella from Mboro distinguishes itself from other populations and then, can be regarded as a sub-population. Thus, the phylogenetic trees reveal the existence of two groups of P. xylostella in Senegal.

关键词： Brassica oleracea Genetic Diversity Genetic Structure

Effect of sustained virological response on long-term clinical outcome in 113 patients with compensated hepatitis C-related cirrhosis treated by interferon alpha and ribavirin

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World Journal of Gastroenterology 2007年第42期13卷 5648-5653页

作者： Roland El Braks Nathalie Ganne-Carrié Hélène Fontaine Jacques Paries Véronique Grando-Lemaire Michel Beaugrand Stanislas Pol Jean-Claude Trinchet Department of Hepatology Hopital Jean Verdier (AP-HP) and UPRES EA 3409 (University Paris 13) Bondy 93140 France Department of Hepatology Hopital Cochin (AP-HP) and University Paris 5 Paris 75014 France Department of Public Health Jean Verdier Hospital (AP-HP) and UPRES EA 3409 (University Paris 13) Bondy 93140 France

AIM： To assess the long-term clinical benefit of sustained virological response （SVR） in patients with hepatitis C virus （HCV） cirrhosis treated by antiviral therapy using mostly ribavirin plus interferon either standard or ***： One hundred and thirteen patients with uncomplicated HCV biopsy-proven cirrhosis, treated by at least one course of antiviral treatment ≥ 3 mo and followed ≥ 30 mo were included. The occurrence of clinical events [hepatocellular carcinoma （HCC）, decompensation and death] was compared in SVR and non SVR ***： Seventy eight patients received bitherapy and 63 had repeat treatments. SVR was achieved in 37 patients （33%）. During a mean follow-up of 7.7 years, clinical events occurred more frequently in non SVR than in SVR patients, with a significant difference for HCC （24/76 vs 1/37, P = 0.01）. No SVR patient died while 20/76 non-SVR did （P = 0.002）, mainly in relation to HCC （45%）.CONCLUSION： In patients with HCV-related cirrhosis, $VR is associated with a significant decrease in the incidence of HCC and mortality during a follow-up period of 7.7 years. This result is a strong argument to perform and repeat antiviral treatments in patients with compensated cirrhosis.

关键词： Hepatitis C Cirrhosis Interferon alpha

Multimodal imaging in Purtscher-like retinopathy associated with sarcoidosis:a case report

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International Journal of Ophthalmology(English edition) 2022年第5期15卷 845-847页

作者： Héla Kaoual Inés Hachicha Ilhem Mili Boussen Imène Zhioua-Braham Mejdi Boukari Raja Zhioua Department of Ophthalmology Charles Nicolle University HospitalTunis 1007Tunisia Faculty of Medicine of Tunis University of Tunis-El ManarTunis 1006Tunisia

Dear Editor,We report a case of Purtscher-like retinopathy(PLR)in the presence of acute pancreatitis secondary to *** our knowledge,this is the first case report of a PLR in a patient with sarcoidosis.

关键词： acute sarcoidosis Purtscher