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Cromatografia líquida e análises quimiométricas na diferenciação química de acessos de Lippia alba (Mill) N. E. Brown e potenciais biológicos / Liquid Chromatography and chemometric analysis for the chemical differentiation of access of Lippia alba (Mill) N. E. Brown and biological potentialsJesus, Raphael Amancio 20 February 2018 (has links)
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The methodology developed in the present work, through chromatographic
fingerprint by LC-DAD and Principal Component Analysis (PCA), was adequate
for the chemical differentiation of Lippia alba (Mill) NE Brown accessions,
considering the extraction method (infusion and maceration hydroalcoholic) and
the collection season (summer and winter), allowing to evaluate the influence of
these variables on the chemical composition of extracts obtained. In addition, all
extracts were submitted to cytotoxic tests against two tumor cell lines, HL-60
(human leukemia) and HepG2 (human hepatocellular carcinoma), and to
inhibition tests against the enzyme acetylcholinesterase (AChE) in order to
evaluate the form of extraction and which access is the most promising from a
pharmacological point of view. Among the extracts analyzed against tumor
cells, eight of them, two from the infusion: 01IW and 02IW and six from the
hydroalcoholic extraction: 02HW, 24HW, 39HW, 54HW, 01HS and 24HS,
presented better cell inhibition performances against HL-60, with percentage of
inhibition between 40.0 and 52.0%, suggesting that these extracts are
potentially promising against this lineage. With respect to the anticholinesterase
tests, all extracts studied had low AChE inhibitory effect when compared to
galantamine (87.4%), highlighting only the samples 01HW (28.4%), 02HW
(27.2%), 54HW (29.3%), 01HS (32.7%), 02HS (27.4%) and 24HS (30.3%).
Through the analyzes performed by Nuclear Magnetic Resonance (NMR) it was
possible to identify the structures of some compounds isolated from this
species: flavone tricin and phenylpropanoid verbascoside/isoverbascoside. In
addition, the classes of three other metabolites were proposed: two
phenylpropanoid derivatives and one flavonoid diglucoside. / A metodologia desenvolvida no presente trabalho, utilizando fingerprint
cromatográfico por CL-DAD e Análise de Componentes Principais (PCA), se
mostrou adequado para a diferenciação química de acessos de Lippia alba
(Mill) N. E. Brown, considerando o método de extração (infusão e maceração
hidroalcoólica) e a época de coleta (verão e inverno), permitindo, ainda, avaliar
a influência destas variáveis na composição química dos extratos obtidos.
Adicionalmente, todos os extratos foram submetidos a testes citotóxicos frente
a duas linhagens de células tumorais, HL-60 (leucemia humana) e HepG2
(carcinoma hepatocelular humano), e de inibição enzimática frente a
acetilcolinesterase (AChE) com o intuito de avaliar qual a forma de extração e
qual acesso é o mais promissor do ponto de vista farmacológico. Entre todos
os extratos analisados frente as células tumorais, dois provenientes da infusão:
01II e 02II e seis da extração hidroalcoólica: 02HI, 24HI, 39HI, 54HI, 01HV e
24HV, apresentaram melhores desempenhos de inibição frente a HL-60, com
percentual de inibição entre 40,0 e 52,0%, sugerindo que estes extratos são
potencialmente promissores contra esta linhagem. Com relação aos testes
anticolinesterásicos, todos os extratos estudados apresentaram baixo efeito
inibidor da AChE quando comparados a galantamina (87,4%), com destaque
para os extratos 01HI (28,4%), 02HI (27,2%), 54HI (29,3%), 01HV (32,7%),
02HV (27,4%) e 24HV (30,3%). Através das análises realizadas por
Ressonância Magnética Nuclear (RMN) foi possível identificar as estruturas de
alguns dos compostos isolados a partir desta espécie: a flavona tricina e o
fenilpropanóide verbascosídeo/isoverbascosídeo. Além disso, foram propostas
as classes de outros três metabólitos: dois derivados de fenilpropanóides e um
flavonóide diglicosilado. / São Cristóvão, SE
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Exposition fœtale à différentes familles de xénobiotiques en Bretagne : analyse de la matrice méconium / Fetal exposure to different families of xenobiotics in Brittany, France : analysis of meconium matrixMeyer, Marie 22 December 2014 (has links)
Le méconium constitue les premières selles du nourrisson. Cette matrice complexe est analysée dans le cadre du projet « PENEW » (Pregnancy Environment and NEWborn malformations) afin de déterminer si le degré d'exposition fœtale aux xénobiotiques joue un rôle dans la survenue de malformations congénitales. Le but de cette étude était le développement analytique pour la détection et la quantification dans le méconium d’une quarantaine de composés de familles différentes (composés organiques volatils, pesticides, éthers de glycol et les métabolites associés). Trois techniques analytiques différentes et une préparation d’échantillon spécifiques ont été développées pour la détection et la quantification de ces composés dans le méconium. L’application des ces méthodes à 246 échantillons de méconium a montré une exposition fœtale à plusieurs des substances recherchées. / Meconium is the earliest stool of newborns. This complex matrix was analyzed through the "PENEW" project (Pregnancy and Newborn malformations Environment) to determine if the degree of fetal exposure to xenobiotics has an influence in the occurrence of birth defects. The objective of this thesis was developed analytical methods for the detection and quantification of several different families of compounds (volatile organic compounds, pesticides, glycol ethers and their metabolites) in meconium. Three different analytical methods and a specific sample preparation have been developed for the detection and quantification of these compounds in the meconium. The application of these methods to 246 meconium samples showed a fetal exposure to several target compounds.
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La société privée européenne : un projet de société contractuelle et supranationale / The european private company : a contractual and supranational companyGergis, Maryline 13 June 2015 (has links)
Les entrepreneurs n’ont pas manqué de soulever l’importance et la nécessité d’une structure européenne flexible pour répondre aux besoins des PME. En effet l'introduction d'une société à conception contractuelle dans le droit européen revêt de multiples intérêts. D'une part, elle intègre les PME dans la continuité du processus de construction du marché intérieur. D’autre part, elle offre une liberté d’action appréciée par les entrepreneurs qui évoluent dans un marché fortement concurrentiel. Enfin, le caractère contractuel permet au législateur européen de revenir sur la définition des libertés d'établissement et de circulation des capitaux.Aussi encourageant que soit ce projet, il n'en demeure pas moins source d'interrogations et d'inquiétudes. La liberté contractuelle comporte des risques si elle n'évolue pas dans un cadre juridique adapté et protecteur. Cette thèse a pour objectif d’analyser les effets de la transposition de la liberté contractuelle dans le droit européen des sociétés. Pour comprendre la portée de l’adoption du texte relatif à la SPE, cette thèse tentera de définir la liberté contractuelle au sens communautaire, de souligner ses avantages et d’analyser ses inconvénients. / Entrepreneurs consider flexible structures are important to meet European SMES needs. Indeed, the transposition of a contractual company in the European law are very valuable. On the one hand, it includes SMES in the process of construction of internal market. On the other hand, it offers to entrepreneurs a freedom to manage their companies in order to be more competitive. Finally the contractual aspect of the company allows the European parliament to reconsider the definition of freedom of establishment and free movement of capital. As encouraging as this project is, it remains a source of questions and concerns. Contractual freedom could involve risks if it doesn’t evolve in a suitable protective legal framework. This thesis aims to analyze the effects of the transposition of contractual freedom in the European company law. To understand the scope of the adoption of the text relating to the SPE, this thesis will try to define the contractual freedom in EU terms, to emphasize its advantages and disadvantages analyzed
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Étude des interactions PET - Eau minérale dans les eaux embouteillées au Liban et approches analytiques des risques sanitaires / Study of PET interaction with mineral water in lebanese bottled water and analytical approaches of health risksAl Rayes, Layal 13 June 2013 (has links)
L'évaluation de l'inertie des matières plastiques au contact de denrées alimentaires est régie par le règlement européen N°10/2011. Au Liban, l'absence de législations relatives à l'usage des matières en plastiques a conduit à des emballages non contrôlés au niveau de la production et du stockage, ce qui peut induire un risque sanitaire pour le consommateur. L'objectif de ce travail a été d'apprécier les phénomènes de migration des contaminants du PET vers l'eau. Pour cela, l'analyse de certains migrants potentiels a été initiée tels que des COV et des SV afin de vérifier la conformité de leur teneur par rapport aux LMA dans les règlementations internationales. Le dosage des aldéhydes dans l'eau a été effectué par dérivation avec la 2,4-DNPH, suivie d'une étape de préconcentration sur une cartouche en C18, puis séparation et quantification par HPLC-UV. L'analyse des composés SV a été réalisée par SPME-GC-FID sur une fibre en PDMS/DVB. L'analyse des BTEX et du styrène a été réalisée par HS-Trap-GC-FID. Ces méthodes ont été validées conformément à la norme NF T 90-210 avec des LQ inférieures aux LMA. L'analyse des COV dans l'eau embouteillée et dans le PET a été réalisée par HSTrap- GC-MS. La présence de FA, d'AA, de DEP et des BTEX dans l'eau embouteillée en PET a été confirmée. Il a été mis en évidence que la température et l'exposition solaire influencent la migration des aldéhydes. Les concentrations d'AA trouvées après incubation à 40ºC ne sont pas négligeables et peuvent modifier les propriétés organoleptiques de l'eau. L'analyse du PET montre la présence des hydrocarbures, des aldéhydes, des alcools, et des cétones / The inertness’ value of plastics that are on contact with foodstuffs is governed by the European rule N°10/2011. In Lebanon, the lack of the Rules and Regulations of plastics’ usage led for a non-controlled packing in production as in storage, which will cause a sanitary risk to the consumer and to the population. The purpose of this research was to appreciate the migration’s phenomena of contaminants from the PET to the water. For this, there was an analysis of potential migrants such as VOC and SV to verify their tenor’s conformity relative to the MCL in international regulations. The aldehydes’ dosage in the water was performed by the derivation with the 2,4-DNPH, followed by a concentration on a C18 cartridge, then separation and quantification was done by HPLC-UV. The SV compounds’ analysis was realized by SPME-GC-FID method on a PDMS / DVB fiber. The BTEX and the styrene’s analysis was done by HS-trap-GC-FID method. These methods were validated in accordance with standard NF T 90-210 with a LQ less than the MCL. The volatile compounds in the bottled water and in the PET were analyzed by HS-trap-GC-MS method. The presence of FA, AA, DEP and BTEX in the bottled water with the PET was confirmed. It was highlighted that temperature and sun exposition influence the aldehydes’ migration. The acetaldehyde’s concentration after incubation at 40ºC wasn’t negligible and can modify the water’s organoleptic properties. The PET’s analyze reveals the presence of hydrocarbons, aldehydes, alcohols and ketones
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Distribucija opijatnih alkaloida u mozgu / The distribution of opiate alkaloids in brainĐurendić-Brenesel Maja 01 March 2008 (has links)
<p>U ovoj doktorskoj disertaciji je uspešno izvršeno izolovanje opijatnih alkaloida iz humanih bioloških uzoraka (moždanog tkiva, krvi, urina i žuči) kao i bioloških uzoraka <br />eksperimentalnih životinja (moždanog tkiva i krvi) primenom postupka čvrsto-tečne ekstrakcije (SPE-Solid Phase Extraction). Modifikovan je postupak za kvalitativnu i kvantitativnu GC-MS (Gas Chromatography-Mass Spectrometry) analizu bioloških <br />uzoraka. Utvrđena je distribucija opijatnih alkaloida: morfina, kodeina, acetilkodeina, 6-acetilmorfina i heroina u humanim biološkim uzorcima moždanog tkiva (moždanoj kori, moždanom stablu, amigdali i bazalnim jedrima), pri čemu je najveći sadržaj <br />opijata određen u moždanoj kori i bazalnim jedrima, podjednako kod muških i ženskih osoba. Utvrđena je distribucija opijatnih alkaloida: morfina, kodeina, acetilkodeina, 6-acetilmorfina i heroina u biološkim uzorcima moždanog tkiva (moždanoj kori, moždanom stablu, amigdali i bazalnim jedrima) i krvi eksperimentalnih životinja (pacova), u <br />različitim vremenskim periodima (5, 15, 45 i 120 minuta) od tretiranja životinja heroinom. Najveći sadržaj opijata je određen u moždanoj kori i bazalnim jedrima, podjednako kod mužjaka i ženki pacova ali u različitim vremenskim periodima. U uzorcima krvi je najveći sadržaj opijata određen u istom vremenskom periodu kod životinja oba pola, pri čemu su kod mužjaka određene znatno veće vrednosti koncentracija, što ukazuje na bržudistribuciju opijata iz krvi u mozak kod ženki u odnosu na mužjake pacova. Utvrđeno je da je distribucija opijata u humanom moždanom tkivu kod pripadnika suprotnih polova kao i moždanom tkivu mužjaka i ženki pacova (nakon 120 minuta od tretiranja heroinom), identična. Ispitivanjem uticaja opijata na markere oksidativnog stresa u jetri eksperimentalnih životinja suprotnih polova, utvrđeno je smanjenje aktivnosti enzima: katalaze (CAT), glutation-peroksidaze (GSH- Px), peroksidaze (Px) i ksantin-oksidaze (XOD).</p> / <p>Opiate alkaloids were successfully isolated from human biological samples (brain tissue, blood, urine, and bile) as well as from biological samples of experimental animals (brain tissue and blood) by applying procedure of solid-phase extraction (SPE). A modified procedure was worked out for qualitative and quantitative analysis of biological samples by gas chromatography-mass spectrometry (GC-MS). The distribution of opiate alkaloids:morphine, codeine, acetylcodeine, 6-acetylmorphine, and heroine in human biological samples of brain tissue (cortex, brain stem, amigdala and basal nuclei) was established, showing the highest content of opiates in the cortex and basal nuclei, equal with male and female persons. It was established how the opiatealkaloids: morphine codeine, acetylcodeine, 6-acetylmorphine and heroine are distributed in biological samples of brain tissue (cortex, brain stem, amigdala and basal nuclei) and blood of experimental animals (rats) in different time periods (5, 15, 45 and 120 min) after the animal treatment with heroine. The highest content of opiates was found in the cortex and basal nuclei, equal in the male and female rats, but in different time periods. In blood samples, the highest content of opiates was measured in the same period with animals of both sexes, the concentration in the males being significantly higher, indicating a faster passage of the opiates from blood to brain in the female compared to male rats. Identical distribution of opiates was found in human brain tissue of both male and female subjects as in rats of both sexes (120 min after treatment with heroine). Study of the effect of opiates on the markers of oxidative stress in the liver of tested animals of opposite sexes showed a lowered activity of the following enzymes: catalase (CAT), glutathion-peroxidase (GSH-Px), peroxidase (Px) and xanthine-xidase (XOD).</p>
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Stanovení nonylfenolu a jeho izomerů ve vodách / Determination of nonylphenol and its isomers in watersSedláček, Jaroslav January 2013 (has links)
This diploma thesis is focused on the issue of nonylphenol, degradation product of surfactants. Nonylphenol however most often arises in wastewater treatment plants predominantly during the microbial degradation of nonylphenol ethoxylates used in industry. It is a substance highly bioaccumulative, toxic predominantly to aquatic organisms. Furthermore, it belongs among hormone disruptors. The detailed research was prepared, on the basis which experimental part of diploma thesis was solved. Nonylphenol was determined in samples of the wastewater. The solid phase extraction (SPE) was used for the isolation of the analyte and purification of the extract. The final determination was performed on the gas chromatography with tandem mass spectrometry with time of flight analyzer (TOF). All steps of the preanalytical and the analytical procedure were optimized.
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Využití separačních metod pro studium biologicky aktivních látek ve vodách / The Usage of Separation Methods for Research of Biologically Active Substances in WatersVydrová, Lucie January 2011 (has links)
Pharmaceuticals are biological active compounds with different functional groups, physico-chemical and biological properties. These chemical compounds are called as “new contaminants” which cumulate in various environmental components. These contaminants input to environment from industrial processes, hospitals and health care institutions or household sources and these pollutants can to negatively interact with environmental components. Pharmaceuticals are separated according to structure and their effects to live organisms. On the basis of drug consumption in Czech Republic the non-steroidal anti-inflammatory drugs are the most using pharmaceuticals, because these drugs can be obtain without prescriptions. The choosing analgesics for study were monitored in waste water from waste waters treatment plant (WWTP Brno – Modřice) and in surface water from two sampling sites of river Kretinka. Pharmaceuticals were monitored in surface waters in Czech Republic, in Scotland (river Thurso) and in Taiwan (river Erren, Agongdian, Yanshuei and canal of Tainan) Solid phase extraction (SPE) is used for extraction of study pharmaceutical from water system. The high performance liquid chromatography (HPLC) with diode array detection or mass spectrometry was used for determination of drugs in surface waters from Czech Republic. The water samples from Scotland and Taiwan were analysed and the high performance liquid chromatography with mass spectrometry (HPLC/MS) was used for determination of pharmaceuticals. The method of HPLC/MS enables the determination of study compounds in the very low range of concentrations (ng ? l-1). All monitored pharmaceuticals were identified and quantified in water samples from river Kretinka in Czech Republic, river Thurso (Scotland) and rivers Erren, Agongdian, Yanshuei and canal of Tainan in Taiwan and the obtained data were compared.
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Stanovení léčiv pomocí HPLC s různými typy detektorů / Determination of drugs by HPLC with different detectorsBenešová, Markéta January 2011 (has links)
This diploma thesis deals with the determination of macrolide antibiotics in wastewater, especially with erythromycin, clarithromycin and roxithromycin. In this time are these pharmaceuticals prescribed quite frequently. Solid phase extraction (SPE) was used for the isolation and the purification of selected analytes from an aqueous matrix; as the suitable procedure was found the using Oasis HLB cartridges. High performance liquid chromatography with mass spectrometry detection (HPLC-MS) was optimized for its analysis of selected pharmaceuticals. The optimized method was used for the determination of pharmaceuticals in real water samples, which was taken at the inflow and the outflow of the urban wastewater treatment plant in Brno-Modřice.
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Detection, analysis, and photocatalytic destruction of the freshwater taint compound geosminBellu, Edmund January 2007 (has links)
A significant issue affecting the aquaculture and water industries is the presence of off-flavour compounds in water, which cause problems by imparting an undesirable earthy/musty flavour and smell to water and fish. Two predominant off-flavour compounds are geosmin (GSM) and 2-methylisoborneol (MIB). These compounds are produced by several varieties of cyanobacteria and actinomycetes as metabolic products and can be detected by humans at concentrations as low as 0.015 mg L-1. Removal of GSM and MIB from potable waters has proven to be inefficient using standard water treatment such as filtration, coagulation, flocculation, sedimentation and chlorination. Activated carbon and membrane processes can physically remove GSM and MIB, but do not destroy them, and ozone treatment can be expensive. Titanium dioxide (TiO2) photocatalysis has recently been demonstrated to rapidly degrade GSM and MIB. When the semiconductor catalyst is illuminated with ultraviolet light simultaneous oxidation and reduction reactions occur. Pollutants are broken down into mineral acids, carbon dioxide and water. This study was conducted to determine if TiO2 photocatalysis, using a pelleted form of TiO2 called Hombikat K01/C, was a suitable method for the treatment of potable water. Additionally an analytical method was developed to rapidily analyse the large number of samples generated. Two reactors, a bench scale batch reactor and pilot scale flow reactor, were developed and used to evaluate the efficacy of Hombikat K01/C TiO2 photocatalysis in degrading GSM. The batch reactor, containing Hombikat K01/C, was used to investigate the effect of numerous experimental variables on the photocatalysis of GSM, including initial substrate concentration, pH, light intensity, aeration rate, the presence of additional reactants, and catalysis conducted in deuterated water. GSM was rapidly degraded using the TiO2 batch reactor, with the rate of GSM degradation most affected by light intensity and additional reactants, though pH also had a notable effect. A kinetic isotope effect of 1.61 was observed for the destruction of GSM using Hombikat K01/C TiO2. The flow reactor was also found to efficiently degrade GSM in raw waters. The rate of GSM destruction was found to be significantly lowered by UV shielding of the catalyst, caused by constituents of raw the water used, and the presence of additional reactants. The pilot scale flow reactor was also successfully evaluated in Denmark using gesomin contaminated water from an eel farm
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The evolution of LOL, the secondary metabolite gene cluster for insecticidal loline alkaloids in fungal endophytes of grasses.Kutil, Brandi Lynn 15 May 2009 (has links)
LOL is a novel secondary metabolite gene cluster associated with the production of loline alkaloids (saturated 1-aminopyrrolizidine alkaloids with an oxygen bridge) exclusively in closely related grass-endophyte species in the genera Epichloë and Neotyphodium. In this study I characterize the LOL cluster in E. festucae, including the presentation of sequence corresponding to 10 individual lol genes as well as defining the boundaries of the cluster and evaluation of the genomic DNA region flanking LOL in E. festucae. In addition to characterizing the LOL cluster in E. festucae, I present LOL sequence from two additional species, Neotyphodium coenophialum and Neotyphodium sp. PauTG-1. Together with two recently published LOL clusters from N. uncinatum, these data allow for a powerful phylogenetic comparison of five clusters from four closely related species. There is a high degree of microsynteny (conserved gene order and orientation) among the five LOL clusters, allowing us to predict potential transcriptional co-regulatory binding motifs in lol promoter regions. The relatedness of LOL clusters is especially interesting in light of the history of interspecific hybridizations that generated the asexual, Neotyphodium lineages. In fact, three of the clusters appear to have been introduced to different Neotyphodium species by the same ancestral Epichloë species, for which present day isolates are no longer able to produce lolines. To address the evolutionary origins of the cluster we have investigated the phylogenetic relationships of particular lol ORFs to their paralogous primary metabolism genes (and gene families) from endophytes, other fungi and even other kingdoms. I present extensive evidence that at least two individual lol genes have evolved from primary metabolism genes within the fungal ancestors of endophytes, rather than being introduced via horizontal gene transfer. I also present complementation studies in Neurospora crassa exploring the functional divergence of one lol gene from its primary metabolism paralog. While it is clear that these insecticidal compounds should convey a selective advantage to the fungus and its host, thus explaining preservation of the trait, this analysis provides an exploration into the evolutionary origin and maintenance of the genes that comprise the LOL and the cluster itself.
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