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Neuromodulation in the Olfactory Bulb / Neuromodulation dans le bulbe olfactifSmith, Richard 08 July 2015 (has links)
La neuromodulation de circuits olfactifs par l'acétylcholine (ACh) joue un rôle important dans la discrimination et l'apprentissage d’odeur. Le traitement précoce des signaux chimiosensoriels se produit dans deux régions fonctionnellement et anatomiquement distinctes, les principaux et accessoires bulbes olfactifs (MOB et AOB), qui reçoivent entrée cholinergique significative du cerveau antérieur basal. Ici, nous explorons la régulation des circuits de l’AOB et la MOB par ACh, et comment cette modulation influence le comportement à médiation olfactifs. De manière surprenante, malgré la présence d'un circuit conservé, l'activation des récepteurs muscariniques de l'ACh révèle des différences marquées dans la modulation cholinergique des neurones de sortie: l’excitation de l’AOB et l'inhibition de la MOB. Les cellules granulaires (GCs), le neurone intrinsèque le plus abondant dans l'OB, présentaient également une réponse muscarinique complexe. Alors que les GCs de l’AOB ont été excitées, les GCs de la MOB présentaient une action muscarinique double, une hyperpolarisation et une augmentation de l'excitabilité non couvert par la dépolarisation cellulaire. Par ailleurs, l’ACh a eu un effet différent sur la relation d'entrée / sortie des MCs dans l’AOB et la MOB, montrant un effet net sur le gain en les MCs de la MOB, mais pas dans l'AOB. Fait intéressant, malgré les différences frappantes dans les actions neuromodulateurs sur les neurones de sortie, l'inhibition de la libération d'ACh chemogenetic produit des perturbations similaires dans les comportements olfactifs médiés par ces deux régions. La diminution de l’ACh dans l'OB a perturbé la discrimination naturelle des odeurs liées moléculairement et l'enquête naturelle des odeurs associées à des comportements sociaux. Ainsi, la neuromodulation distincte par l’ACh dans ces circuits pourrait déclencher des solutions différentes générales pour le traitement des odeurs et les médiateurs chimiques, ainsi que les comportements olfactifs diverses qu'ils déclenchent. / Neuromodulation of olfactory circuits by acetylcholine (ACh) plays an important role in odor discrimination and learning. Early processing of chemosensory signals occurs in two functionally and anatomically distinct regions, the main and accessory olfactory bulbs (MOB and AOB), which receive significant cholinergic input from the basal forebrain. Here we explore the regulation of AOB and MOB circuits by ACh, and how this modulation influences olfactory mediated behaviors. Surprisingly, despite the presence of a conserved circuit, activation of muscarinic ACh receptors revealed marked differences in cholinergic modulation of output neurons: excitation in the AOB and inhibition in the MOB. Granule cells (GCs), the most abundant intrinsic neuron in the OB, also exhibited a complex muscarinic response. While GCs in the AOB were excited, MOB GCs exhibited a dual muscarinic action, a hyperpolarization and an increase in excitability uncovered by cell depolarization. Furthermore, ACh had a different effect on the input/output relationship of MCs in the AOB and MOB, showing a net effect on gain in MCs of the MOB, but not in the AOB. Interestingly, despite the striking differences in neuromodulatory actions on output neurons, chemogenetic inhibition of ACh release produced similar perturbations in olfactory behaviors mediated by these two regions. Decreasing ACh in the OB disrupted the natural discrimination of molecularly related odors and the natural investigation of odors associated with social behaviors. Thus, the distinct neuromodulation by ACh in these circuits could underlie different solutions to the processing of general odors and semiochemicals, and the diverse olfactory behaviors they trigger.
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Antimicrobial activity of indigenous bulbous plant extracts to control selected pathogensLouw, Catharina Aletta Magdalena 10 October 2005 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MInst Agrar (Plant Protection))--University of Pretoria, 2005. / Microbiology and Plant Pathology / unrestricted
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Systematic significance of bulb morphology of the Southern African members of Oxalis L. (Oxalidaceae)Gebregziabher, Awot Kiflu 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The systematics of the southern African members of the genus Oxalis L. (Oxalidaceae) is in a
state of flux. The bulbs of these species contain potential taxonomically important characters
and therefore require detailed study (Salter, 1944). A pilot study assessed the homology of
bulbs among southern African Oxalis species (Gebregziabher, 2001), and found that they are
all homologous structures. This pilot study also emphasized the range of potentially
informative characters from different bulb parts.
The aim of the present study was to assess the taxonomic significance of bulb morphology in
selected southern African Oxalis species. As far as possible, efforts were made to represent
both the taxonomic (Salter, 1944) and palynological diversity (Dreyer, 1996) present in the
genus.
Detailed bulb morphological studies of 30 species of southern African Oxalis species revealed
41 potentially informative characters. Different bulb-types were identified based on these
characters. Bulb-type affinities of taxa included in this study, as well as bulb descriptions
from the pilot study (Gebregziabher, 2001), were discussed. Comparison with the current
taxonomic classification (Salter, 1944), palynological classification (Dreyer, 1996) and a
preliminary phylogeny based on the non-coding plastid trnL-trnF DNA region (Oberlander,
2003), were also made. Bulb morphology conflicted with the current taxonomic classification
(Salter, 1944), but showed greater congruence with both the palynological groupings and the
trnL-trnF based phylogeny.
Based on this study, bulb morphology is found to be taxonomically significant. Further
studies on the bulb morphology and anatomy of southern African Oxalis species are merited.
Key words: bulb morphology, Oxalis, informative characters, basal plates, fleshy leaves,
tunics / AFRIKAANSE OPSOMMING: Die sistematiek van die suider Afrikaanse lede van Oxalis L. (Oxalidaceae) is labiel. Die bolle
van hierdie spesies sluit potensieel taksonomies belangrike kenmerke in, en behoort daarom in
detail bestudeer te word (Salter, 1944). In Loodsstudie het die homologie van die bolle van die
suider Afrikaanse Oxalis spesies ge-evalueer (Gebregziabher, 2001), en gevind dat hulle
homoloë strukture is. Resultate van hierdie loodsstudie het ook die reeks van potensieel
informatiewe kenmerke van verskillende boldele beklemtoon.
Die doel van hierdie studie was om die taksonomiese belang van boImorfologie in
geselekteerde suider Afrikaanse Oxalis spesies te ondersoek. Pogings is aangewend om, sover
moontlik, beide die taksonomiese (Salter, 1944) en die palinologiese (Dreyer, 1996)
diversiteit van die genus in die studie in te sluit.
Gedetailleerde bol-morfologiese studies van 30 suider Afrikaanse Oxalis spesies het 41
potensieel informatiewe kenmerke uitgewys. Gebaseer op hierdie kenmerke, is verskillende
bol-tipes geïdentifiseer. Verwantskappe tussen die bol-tipes van die spesies ingesluit in
hierdie studie, sowel as beskrywings van bolle volgens die loodsstudie (Gebregziabher, 2001),
word bespreek. Vergelykings met die huidige taksonomiese klassifikasie (Salter, 1944),
palinologiese klassifikasie (Dreyer, 1996) en In voorlopige filogenie gebaseer op die niekoderende
plastied trnL-F DNA-streek (Oberlander, 2003) is ook getref. BoImorfologie
weerspreek die huidige taksonomiese klassifikasie (Salter, 1944), maar toon groter
ooreenstemming met beide die palinologiese groeperings en die trnL-F gebaseerde filogenie.
Hierdie studie het bevind dat bolmorfologie van taksonomiese waarde is. Verdere studies op
die bolmorfologie en -anatomie van die suider Afrikaanse Oxalis spesies word aanbeveel.
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Marketingový mix / Marketing mixČERMÁK, Pavel January 2013 (has links)
The thesis aims to analyze the current situation regarding the marketing mix in the selected company. Based on this analysis it was found that the current marketing mix should be adjusted in an attempt to increase sales and brand awareness. It was suggested solutions to improve the situation, which consists of improvement proposals. These proposals focus according to the results of the SWOT analysis to improve brand image and expand its presence among the customers. It is also trying to solve the problem with the purchasing power of customers, not least the problem of obtaining customers. Two selected suggestions, which attempts to solve the problem of obtaining customers and also partly to raise awareness about the company and its operations were subsequently tested market.
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Potravní preference drobných zemních savců a jejich vliv na biodiverzitu rostlinných společenstev mokrých orchidejových luk / Food preferences of small terrestrial mammals and their influence on biodiversity of plant communities in wet orchid meadowsCUDLÍN, Ondřej January 2008 (has links)
Food preference of small rodents to consume the roots of wild plants with the emphasize on their impact to bulbs of orchid Dactylorhiza majalis has been studied on three localities during years 2002 - 2007. There were selected ten couples of plants in each plots, one individual of couple plants was protected by tin triangle. Indicated plants have been measured in the beginning (high, length and wide of the leaves and flower number) and at the end of growing period (number of capsules). Small mammals were snaptrapped for three nights in the autumn. On each locality four rows of 25 snap traps were situated, two rows through orchid plots and two without orchids. In years 2004 {--} 2007 the food preference was ascertained on studied sites. Roots of Daucus carota (as a control in year 2004) and roots of Selinum carvifolia (as control in years 2005 - 2007) and roots of tested plant were put into one rectangle "bait" of size 15 x 6 centimeters from gauze. These 50 "baits" were placed among 100 traps on each locality, every other trap, during snaptrapped of small mammals. Browsing was classified by six number scale. During years 2005 - 2007 food preference of Microtus arvalis under laboratory conditions of Science Faculty of South Bohemia University was achieved with the roots of the same species as we used during food preference on plots. During years 2006 -2007 bulbs of Dactylorhiza majalis from laboratory condition and a few idividuals from endengered meadows by revitalization of pond were added. During yeas 2006 and 2007 the contain of stomach from Microtus arvalis and Microtus agrestis, catched during autumn, was studied. Bulb destruction by small rodents during years 2002 - 2007 was not confirmed. But Microtus arvalis preferred bulbs of Dactylorhiza majalis under laboratory conditions and roots of Selinium carvifolium and Lysimachia vulgaris boths in laboratory and wet meadows. Destruction of orchid bulbs and more preferred roots of wild plants by small rodents could occur probably only in outbreaks of their population cycle. I did not observe this on studied plots. In mount of stomach from Microtus arvalis only 3% underground supply organs of plants; rest of stomach contain was consisted of aboveground green part of plants. This result was expexted, because small rodents prefere during vegetation period green part of plants.
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台灣現代零售通路之省電燈泡需求管理 / THE DEMAND MANAGEMENT OF ENERGY-SAVING BULBS IN TAIWAN MAJOR MODERN RETAIL CHANNELS: THE FORECAST PERSPECTIVE蘇淑卿, Su,Shu Ching Unknown Date (has links)
台灣現代零售通路之省電燈泡需求管理 / THE DEMAND MANAGEMENT OF ENERGY-SAVING BULBS IN TAIWAN MAJOR MODERN RETAIL CHANNELS: THE FORECAST PERSPECTIVE
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Seasonal pharmacological and phytochemical properties of medicinal bulbs.Ncube, Bhekumthetho. January 2010 (has links)
Medicinal bulbs form part of the diversified flora in South Africa. The plants are used extensively in South African traditional medicine in the treatment of various ailments. Due to the ever-increasing demand and the unrestricted collection of medicinal plants from the wild, many of these slow growing bulbous plant species are driven into over-exploitation and extinction. The main parts collected for use are the underground bulbs, leading to the destructive harvesting of the whole plant. This form of plant harvesting poses threats to the long term sustainability of these plant resources from their natural habitats. Sustainable harvesting of these plants should be within the limits of their capacity for self-renewal. However, this seldom occurs with the often inconsiderate medicinal plant gatherers. Conservation of these plants is therefore necessary. A strategy that would take into consideration the sustainable harvesting and perhaps simultaneously provide similar medicinal benefits, would be the substitution of bulbs with leaves of the same plant. This study was aimed at evaluating the seasonal pharmacological and phytochemical properties in bulbs/corms and leaves of medicinal bulbs with a view of promoting the substitution of bulbs with leaves in traditional medicinal use. Four medicinal bulbous plants, Tulbaghia violacea, Hypoxis hemerocallidea, Drimia robusta and Merwilla plumbea were evaluated for the pharmacological and phytochemical properties in their bulbs/corms and leaves in spring, summer, autumn and winter seasons, with a view of promoting the use of leaves as a conservation strategy. Dried plant materials were sequentially extracted with petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water in each season. The extracts were tested for activities against Gram-positive (Bacillus subtilis and Staphylococcus aureus), Gram-negative (Escherichia coli and Klebsiella pneumoniae) bacteria and the fungus Candida albicans using the in vitro microdilution assays to obtain minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC). The four plant species were also evaluated for their ability to inhibit cyclooxygenase (COX-1 and COX-2) enzymes. Spectrophotometric methods were used to evaluate saponin and phenolic contents of samples from the four plant species in each season.
Antibacterial activity was fairly comparable between bulbs/corms and leaves of H. hemerocallidea, T. violacea, and M. plumbea, with at least one extract showing some good activity (MIC < 1 mg/ml) in most of the seasons. Bulb extracts of D. robusta did not show good antibacterial activity while the leaf extracts showed good activity (0.78 mg/ml) against B. subtilis in spring, summer, and autumn and S. aureus (0.78 mg/ml) in autumn. The best antibacterial activity was recorded in winter, with MIC values as low as 0.195 mg/ml from the DCM bulb extracts of T. violacea against K. pneumoniae and S. aureus and PE corm extracts of H. hemerocallidea (0.195 mg/ml) against B. subtilis. Good antibacterial activity from water extracts were only recorded from corm extracts of H. hemerocallidea in summer, autumn and winter, H. hemerocallidea leaf extracts in autumn and winter, and M. plumbea bulb extracts in autumn. The leaf extracts of all the screened plant species demonstrated good fungicidal activity in autumn, with H. hemerocallidea corm water extracts recording an MFC value as low as 0.39 mg/ml. The leaf extracts of H. hemerocallidea (water), D. robusta (DCM) and M. plumbea (DCM) had good MFC values of 0.78 mg/ml each, in spring. The DCM leaf extracts of T. violacea also showed good fungicidal activity (0.78 mg/ml) in summer, while corm water extracts of H. hemerocallidea had an MFC value of 0.39 mg/ml in winter. There were no fungicidal activities recorded from all the bulb extracts in all the seasons. All the PE and DCM extracts in all the tested plant samples recorded between moderate (40-70%) and high (> 70%) COX-1 and COX-2 inhibition levels across all seasons. The EtOH corm extracts of H. hemerocallidea also demonstrated moderate to high inhibitory activity against COX-1 enzyme across all seasons. Bulb and leaf extracts of T. violacea showed selective inhibitory activity for COX-2 enzyme in all the seasons. The highest COX inhibitory levels were recorded in COX-2 from the PE leaf (spring) and bulb (autumn) extracts of T. violacea, with both recording 100% inhibitory activity.
Phytochemical analysis revealed higher total phenolic compounds in bulbs/corms and leaves of all the analysed plant species, to be either higher in spring or winter. Plant material collected in autumn had the least levels of total phenolics. An almost similar trend to that of total phenolics was observed for flavonoids, gallotannins and condensed tannins in most plant samples, with higher levels either in spring or
winter. Total saponins were consistently higher in winter than in the other seasons in all the screened plant species. There were in some cases, relationships between the peaks in the levels of some phytochemical compounds and the observed levels of bioactivity in different assays. The results obtained from this study demonstrate that the leaves of the screened plant species may substitute or complement bulbs in the treatment of certain ailments in traditional medicine. Thus, plant part substitution can be sustainably utilised in the conservation of these plant species while retaining the same medicinal benefits. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
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Biologická aktivita obsahových látek rostlin XXVIII. Alkaloidy vybraných odrůd taxonu Narcissus cyclamineus REDOUTÉ a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu. / Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesteraseJanura, Michal January 2015 (has links)
Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesterase. JANURA M.: Diploma work, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015, Czech Republic. Abstract: The summary extracts of alkaloids from bulbs of N. cyclamineus esp. N. cyclamineus cv. Jenny, N. cyclamineus cv. Little Witch, N. cyclamineus cv. Rapture, N. cyclamineus cv. Surfside, N. cyclamineus cv. Peeping Tom, N. cyclamineus cv. Warbeld and N. cyclamineus cv. Skater's Waltz were obtained by the procedures common for this type of compounds. The alkaloid extracts were analyzed by GC/MS and the probable occurrence of individual alkaloid substances was observed. These extracts were also assayed for HuAChE and HuBuChE inhibitory activity. N. cyclamineus cv. Surfside with IC50 = 61,26 ± 6,42 µg/ml and N. cyclamineus cv. Warbeld with IC50 = 85,43 ± 11,13 µg/ml have the best results in inhibition of HuBuChE. The best inhibitory activity on HuAChE has N. cyclamineus cv. Warbeld with IC50 (HuAChE) = 36,82 ± 4,50 µg/ml. Key words: Narcissus, Acetylcholinesterase, Butyrylcholinesterase, GC/MS, Alzheimer's disease.
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Biologická aktivita obsahových látek rostlin XXIX. Alkaloidy vybraných odrůd taxonu Narcissus triandrus L. a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu / Biological activity of plant metabolites XXIX. Alkaloids from selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesteraseFarkašovský, Marek January 2015 (has links)
Farkašovský M.: Biological activity of plant metabolites XXIX. Alkaloids of selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesterase. Diploma thesis. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of pharmaceutical botany and ecology, Hradec Králové 2015, 70 pages Screening of seven bulb samples of Narcissus genus was performed. It included cultivars Narcissus triandrus cv. Hawera, Narcissus triandrus cv. Ice Wings, Narcissus triandrus cv. Stint, Narcissus triandrus cv. Tresamble, Narcissus cyclamineus cv. February Gold, Narcissus cyclamineus cv. Greenlet and Narcissus cyclamineus cv. Itzim. Primary extract was prepared by boiling crushed bulbs in ethanol 95% and then it was condensated. After extraction in diethyl ether and ethyl acetate was pure alkaloid extract dried with air flow in water bath. Isolated alkaloid extracts were tested for their inhibition activity on acetylcholinesterase and butyrylcholinesterase. Also GC-MS analysis was provided to identify alkaloids. These alkaloids were identified with GC-MS analysis - epinorgalanthamine, galanthamine, galanthine, haemanthamine, hippeastrine, homolycorine, cherylline, incartine, lycoramine, lycoramine-acetate, lycorine, narwedine, neruscine, sanguinine...
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Le syndrome CHARGE : étude clinique et moléculaire / Clinical and molecular aspects of CHARGE syndromeLegendre, Marine 14 December 2016 (has links)
Le syndrome CHARGE est une association malformative rare due à une mutation du gène CHD7 dans 60 à 90% des cas. L'objectif de ce travail était d'en décrire les éléments cliniques et moléculaires afin d'optimiser la prise en charge de patients atteints d'un handicap multisensoriel lourd.Le diagnostic anténatal en est difficile et l'étude de 40 fœtus a permis d'affiner la description du phénotype, de décrire de nouveaux éléments cliniques et finalement de proposer un ajustement des critères diagnostiques chez le fœtus.L'étude endocrinienne de 42 patients confirme la présence d'un hypogonadisme hypogonadotrope dans 97% des cas. Souvent méconnu et non traité il peut avoir des conséquences délétères sur la qualité de vie. Nous proposons qu'il soit reconnu comme critère majeur du syndrome.L'étude clinique d'une cohorte française de 119 patients a montré que la surdité et l'atteinte des canaux semi circulaires sont les éléments les plus fréquents du syndrome (suivis de l'atteinte hypophysaire, de l'arhinencéphalie et des anomalies de l'oreille externe), et les seuls significativement associés à la présence d'une mutation dans CHD7. Une étude approfondie des données issues de cette étude est en cours.Sur le plan moléculaire, alors que la plupart des mutations identifiées sont des mutations tronquantes privées apparues de novo, nous avons identifié 4 variants au niveau de l'intron 25, récurrents pour certains, dont l'interprétation était délicate. Leur étude in silico puis par une technique de minigène a permis de mettre en évidence une configuration particulière des séquences impliquées dans l'épissage de l'exon 26 (point de branchement distant) et de démontrer leur pathogénicité. / CHARGE syndrome is a rare disorder of multiple congenital anomalies ascribed to a CHD7 gene mutation in 60% to 90% of cases. The aim of this study was to improve the knowledge regarding molecular and clinical aspects of the syndrome in order to optimize the management of these patients with severe disability. Antenatal diagnosis remains challenging in many instances and a detailed clinicopathological survey in a series of 40 fetuses allowed us to refine the clinical description of CHARGE syndrome in fetuses, describe some novel features and set up diagnostic criteria. An endocrinologic study of 42 patients showed a hypogonadotrophic hypogonadism in 97% of cases. For this reason, it should be considered as a major symptom of the syndrome. An early screening should lead to a hormonal replacement therapy which dramatically impacts the condition.A study of a French cohort of 119 patients found that deafness and semi-circular canals hypoplasia were the most frequent symptoms (followed by hypogonadotrophic hypogonadism, arhinencephaly and external ears anomalies) and the only features statistically associated with a mutation in the CHD7 gene. A detailed study of the data is still going on.The syndrome is mainly due to de novo and private truncating mutations of the CHD7 gene but we report an intriguing hot spot of intronic mutations located in IVS25. Combining computational in silico analysis and ex vivo minigene assays, we explained this mutation hot spot by a particular genomic context, including a distant branch point, and confirmed the pathogenicity of these mutations.
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