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51.
Stephen F. Omondi Eliud Kireger Otto G. Dangasuk Ben Chikamai David W. Odee Stephen Cavers Damase P. Khasa 《Tropical plant biology》2010,3(1):59-70
The level of genetic diversity and population structure of Acacia senegal variety kerensis in Kenya was examined using seven polymorphic nuclear microsatellite loci and two chloroplast microsatellite loci. In both chloroplast and nuclear datasets, high levels of genetic diversity were found within all populations and genetic differentiation among populations was low, indicating extensive gene flow. Analysis of population structure provided support for the presence of two groups of populations, although all individuals had mixed ancestry. Groups reflected the influence of geography on gene flow, with one representing Rift Valley populations whilst the other represented populations from Eastern Kenya. The similarities between estimates derived from nuclear and chloroplast data suggest highly effective gene dispersal by both pollen and seed in this species, although population structure appears to have been influenced by distributional changes in the past. The few contrasts between the spatial patterns for nuclear and chloroplast data provided additional support for the idea that, having fragmented in the past, groups are now thoroughly mixed as a result of extensive gene flow. For the purposes of conservation and in situ management of genetic resources, sampling could target a few, large populations ideally distributed among the spatial groups identified. This should ensure the majority of extant variation is preserved, and facilitate the investigation of variation in important phenotypic traits and development of breeding populations. 相似文献
52.
Three species of Euryhaliotrema Kritsky & Boeger, 2002 (Monogenoidea: Dactylogyridae) were collected from the gills of four golden snapper Lutjanus johnii (Bloch) (Lutjanidae) from the marine and brackish waters off Darwin, Northern Territory, Australia. Type-specimens of Ancyrocephalus johni Tripathi, 1959 apparently have not survived and the possibility existed that the species was based on specimens representing more than one species. Euryhaliotrema johni (Tripathi, 1959) (sensu Young, 1968) was redescribed and determined to most likely represent A. johni, originally described from the River Hooghly, Diamond Harbour, India. Two new species were described. Euryhaliotrema longibaculoides n. sp. was most similar to Euryhaliotrema longibaculum (Zhukov, 1976) Kritsky & Boeger, 2002 from Lutjanus spp. from the western Atlantic Ocean. It differed from E. longibaculum by having a male copulatory organ (MCO) with an elongate comparatively delicate shaft and a bulbous base (MCO U- or J-shaped with funnel-shaped base in E. longibaculum). Based on the comparative morphology of the haptoral sclerites, Euryhaliotrema lisae n. sp. was most similar to Euryhaliotrema cryptophallus Kritsky & Yang, 2012 from the gills of the mangrove red snapper Lutjanus argentimaculatus (Forsskål) from the South China Sea. Euryhaliotrema lisae differed from E. cryptophallus by having a copulatory complex with an obvious weakly sclerotised J-shaped MCO (MCO cryptic, delicate, and with a shaft comprising about one counterclockwise ring in E. cryptophallus). 相似文献
53.
Ballota L. comprises several relevant species largely used for their excellent therapeutic properties. Ballota hispanica (L.) Benth. is widely used in herbal medicine, and it is sold in herbalist shops for its sedative and antispasmodic properties. Considering its traditional medicinal use and the lack of scientific studies on the volatile components of this species as well as on its biological activities, in this study the chemical composition of the essential oil from aerial parts of B. hispanica, collected in Sicily, was evaluated by gas chromatography and gas chromatography–mass spectrometry. α-Elemol was the most abundant component of the oil (10.9%), followed by α-ylangene (8.5%), γ-dodecalactone (5.1%), and manoyl oxide (4.8%). A comparison was made of the composition of the different Ballota taxa studied so far showing a peculiar profile of B. hispanica. Futhermore, the antimicrobial and the free radical scavenging activities of the oil were determined. 相似文献
54.
Abstract: The role of excitatory amino acid (EAA) receptors located in the ventral tegmental area (VTA) in tonic and phasic regulation of dopamine release in the ventral striatum was investigated. Microdialysis in conscious rats was used to assess dopamine release primarily from the nucleus accumbens shell region of the ventral striatum while applying EAA antagonists or agonists to the VTA. Infusion of the AMPA/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (25 and 100 µ M ) into the VTA did not affect dopamine release in the ventral striatum. In contrast, intra-VTA infusion of the NMDA receptor antagonist 2-amino-5-phosphopentanoic acid (100 and 500 µ M ) dose-dependently decreased the striatal release of dopamine. Intra-VTA application of the ionotropic EAA receptor agonists NMDA and AMPA dose-dependently (10 and 100 µ M ) increased dopamine efflux in the ventral striatum. However, infusion of 50 or 500 µ M trans -(±)-1-amino-1,3-cyclopentanedicarboxylic acid (ACPD), a metabotropic EAA receptor agonist, did not significantly affect these levels. These data suggest that NMDA receptors in the VTA exert a tonic excitatory influence on dopamine release in the ventral striatum. Furthermore, dopamine neurotransmission in this region may be enhanced by activation of NMDA and AMPA receptors, but not ACPD-sensitive metabotropic receptors, located in the VTA. These data further suggest that EAA regulation of dopamine release primarily occurs in the VTA as opposed to presynaptically at the terminal level. 相似文献
55.
A lectin has been isolated from rhizomes of ground elder (Aegopodium podagraria) using a combination of affinity chromatography on erythrocyte membrane proteins immobilized on cross-linked agarose and hydroxyapatite, and ion-exchange chromatography. The molecular structure of the lectin was determined by gelfiltration, sucrose density-gradient centrifugation and gel electrophoresis under denaturing conditions. It has an unusually high Mr (about 480000) and is most probably an octamer composed of two distinct types of subunits with slightly different Mr (about 60000). Hapten inhibition assays indicated that the Aegopodium lectin is preferentially inhibited by N-acetylgalactosamine. Nevertheless, it does not agglutinate preferentially blood-group-A erythrocytes. The ground-elder lectin is a typical non-seed lectin, which occurs virtually exclusively in the underground rhizomes. In this organ it is an abundant protein as it represents up to 5% of the total protein content. The lectin content of the rhizome tissue varies strongly according to its particular location along the organ. In addition, the lectin content changes dramatically as a function of the seasons. The ground-elder lectin differs from all other plant lectins by its unusually high molecular weight. In addition, it is the first lectin to be isolated from a species of the family Apiaceae.Abbreviations APA
Aegopodium podagraria agglutinin
- PBS
phosphate-buffered saline
- SDS-PAGE
sodium dodecyl sulfate polyacrylamide gel electrophoresis 相似文献
56.
We describe here a protocol for the detection of epithelial cells in effusions combined with quantification of apoptosis by flow cytometry (FCM). The procedure described consists of the following stages: culturing and induction of apoptosis by staurosporine in control ovarian carcinoma cell lines (SKOV-3 and OVCAR-8); preparation of effusion specimens and cell lines for staining; staining of cancer cells in effusions and cell lines for cell surface markers (Ber-EP4, EpCAM and CD45) and intracellular/nuclear markers of apoptosis (cleaved caspase-3 and caspase-8, and incorporated deoxyuridine triphosphates); and FCM analysis of stained cell lines and effusions. This protocol identifies a specific cell population in cytologically heterogeneous clinical specimens and applies two methods to measure different aspects of apoptosis in the cell population of interest. The cleaved caspase and deoxyuridine triphosphate incorporation FCM assays are run in parallel and require (including sample preparation, staining, instrument adjustment and data acquisition) 8 h. The culturing of cell lines requires 2-3 days and induction of apoptosis requires 16 h. 相似文献
57.
The Late Jurassic - Early Cretaceous series encountered in South-East Tunisia, formely considered globally as Purbecko-Wealdian in age, has the most complete palaeobotanical record of all North-Gondwana. Thanks to the stratigraphical results of the last years and to new field researches, it was possible, for the first time, to evidence an Oxfordian flora at the base of this series (Bir Miteur Formation). This flora, constituted of impressions and axes of Pteridophytes and Gymnosperms, is encountered within different types of plant-bearing levels. The study of deposit facies and sequential analysis of this Oxfordian formation allowed the identification of corresponding sedimentary environments and to infer their palaeoecological meaning. The discovery of exceptional specimens provided new informations about the general morpho-anatomy of Alstaettia, a very peculiar tree fern of a now extinct type. This Oxfordian flora is an interesting key-point in the evolution of North-Gondwanian flora at the Jurassic/Cretaceous transition. 相似文献
58.
Bouchra Benmansour Feriel Youssef Manel Ben Ali Bander Albogami Fehmi Boufahja 《Saudi Journal of Biological Sciences》2022,29(5):3610-3616
Between 2018 and 2020, 696 fish belonging to two species of sharks from the Family Triakidae (Mustelus mustelus and M. punctulatus) were collected from the coasts of Tunisia and inspected for parasites. Six copepod taxa (Perissopus dentatus Steenstrup & Lütken, 1861, Eudactylinella alba Wilson, 1932, Kroyeria lineata Van Beneden, 1853, Nesippus orientalis Heller, 1865 and Lernaeopoda galei Krøyer, 1837, Kroyeria sp.), four isopod species (Anilocra physodes (Linnaeus, 1758), Emetha audouini (H. Milne Edwards, 1840), Ceratothoa parallela (Otto, 1828) and Ceratothoa oestroides (Risso, 1816)) and two monogenean species (Erpocotyle sp1. And Erpocotyle sp2) were collected. A large number of global host records was reported, including the occurrence of E. audouini on M. mustelus and of Erpocotyle sp.2 on M. punctulatus. The study of the diversity of parasites per host species revealed that M. mustelus had a higher parasitic richness compared to M. punctulatus. In this study, it was provided for the first records on ectoparasites on Triakidae sharks from Tunisian coasts and their infection indices. 相似文献
59.
Proteome analysis reveals novel proteins associated with proliferation and differentiation of the colorectal cancer cell line Caco-2 总被引:26,自引:0,他引:26
Stierum R Gaspari M Dommels Y Ouatas T Pluk H Jespersen S Vogels J Verhoeckx K Groten J van Ommen B 《Biochimica et biophysica acta》2003,1650(1-2):73-91
Here, we describe a proteomics approach to study protein expression changes in differentiating Caco-2 cells. Caco-2 is a colorectal carcinoma cell line, which upon differentiation loses its tumorigenic phenotype and displays characteristics of mature enterocytes, including brush borders with microvilli. Cells were grown in culture flasks and harvested at different stages of differentiation (days post-confluence: -3, 0, 3, 7, 10, 14, and 18). Two-dimensional gel electrophoresis was used to analyse proteome changes. Approximately 1400 protein spots were detected within the Caco-2 proteome, within the pH 4-7 range. Two-dimensional gel electrophoresis allowed for the detection of 18 proteins from which the levels of expression were found to be associated with differentiation. Of these proteins, 11 were identified by means of MALDI-TOF or NANO-ESI-MS/MS mass spectrometry and include liver fatty acid binding protein (FABL), three forms of alpha-enolase (ENOA), nucleoside diphosphate kinase A (NDKA), cofilin-1 (COF1), translationally controlled tumour protein (TCTP), mitochondrial 60-kDa heat shock protein (CH60), probable protein disulfide isomerase (ER60), creatine kinase B (KCRB), and glutathione S-transferase alpha (GTA1). Thus, proteomics revealed that the differentiation-related change in phenotype of Caco-2 involves changes in a variety of distinct biochemical pathways. Some of these proteins have not been shown before to be associated with Caco-2 differentiation (ER60; COF1; CH60; NDKA; TCTP and ENOA). Therefore, processes related to protein folding and disulfide bridge formation, cytoskeleton formation and maintenance, nucleotide metabolism, glycolysis as well as tumorigenesis-associated proteins may be involved in Caco-2 differentiation. Changes in the expression of CH60, TCTP, GTA1, NDKA, and FABL have also been reported to be associated with in vivo colon carcinogenesis. These findings illustrate that a combination of proteomics and cell culture is a useful approach to find markers for Caco-2 differentiation, which could contribute to the comprehension of the process of colon carcinogenesis. 相似文献
60.
Ben Khalaf N De Muylder G Ratnam J Kean-Hooi Ang K Arkin M McKerrow J Chenik M 《Journal of biomolecular screening》2011,16(5):545-551
The use of a high-throughput technique to perform a pilot screen for Leishmania major protein disulfide isomerase (LmPDI) inhibitors identification is reported. In eukaryotic cells, protein disulfide isomerase (PDI) plays a crucial role in protein folding by catalyzing the rearrangement of disulfide bonds in substrate proteins following their synthesis. LmPDI displays similar domain structure organization and functional properties to other PDI family members and is involved in Leishmania virulence. The authors used a method based on the enzyme-catalyzed reduction of insulin in the presence of dithiothreitol. The screen of a small library of 1920 compounds was performed in a 384-well format and led to the identification of 27 compounds with inhibitory activity against LmPDI. The authors further tested the cytotoxicity of these compounds using Jurkat cells as well as their effect on Leishmania donovani amastigotes using high-content analysis. Results show hexachlorophene and a mixture of theaflavin monogallates inhibit Leishmania multiplication in infected macrophages derived from THP-1 cells, although the inhibitory effect on LmPDI enzymatic activity does not necessarily correlate with the antileishmanial activity. 相似文献