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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Quorum Sensing Inhibitory Activities of Various Folk-Medicinal Plants and the Thyme-tetracycline Effect.

Nagy, Maria M 14 December 2010 (has links)
Pseudomonas aeruginosa is an opportunistic, nosocomial pathogen for which antibiotic resistance and biofilm development is common. Quorum sensing communication is known to be a major controlling factor in virulence gene expression, biofilm development, antibiotic resistance factors, and specifically MexAB-OprM multi-drug efflux pump expression in P.aeruginosa. MexAB-OprM efflux pumps contribute to antibiotic resistance of tetracycline and other antibiotics in pseudomonads and other organisms. P.aeruginosa infections are problematic in cystic fibrosis and burn patients; it is also the number one causative agent of respiratory infections for intensive care unit patients. Present day antibiotics are losing the battle against these infections. In theory, quorum sensing inhibitors (QSI) reduce pathogencity of the organism; making it less virulent, thus allowing either the host immune system to clear the infection or use of a QSI in combination with an antibiotic to clear more persistent pathogens. For these reasons two alternative modes of treatment were explored in this study: quorum sensing inhibition by folk-medicinal plant extracts and an example of combination drug therapy, the “thyme-tetracycline effect”. Fifty folk-medicinal plant extracts were screened for potential anti-quorum sensing activity using two quorum sensing inhibition (QSI) reporter strains, Pseudomonas aeruginosa QSIS2 and Chromobacterium violaceum 12725. These were used to test specifically for C4-C6 and C12 HSL quorum sensing inhibition. Of the fifty plants tested, thirty plant families were represented. Eleven plant extracts (basil, chaparral, clove, cranberry, oregano, pomegranate, rosemary, sage, sassafras, thyme and witch hazel) showed C4 HSL quorum sensing inhibition as determined by both assays. Interestingly, five of the plants were from the Lamiaceae family. Thymus vulgaris (thyme), also from the Lamiaceae family, was chosen for further assessment. Previous research has shown that thyme extract can synergistically augment tetracycline activity against tetracycline-resistant Pseudomonas aeruginos, creating the “thyme-tetracycline effect.” Disc diffusion assay, thin layer chromatography (TLC), and TLC bioassay techniques were used to show that thymol is the active component in the thyme extract that augments tetracycline activity against resistant Pseudomonas. This study also showed that thymol is a potent C4 HSL quorum sensing inhibitor. The collective data suggests a potential mode of action for the thyme-tetracycline effect: thymol appears to prevent MexAB-OprM efflux pump gene expression. By blocking MexAB-OprM expression, tetracycline antibiotic accumulation can occur within the cell, thus allowing cellular damage.
282

Anti-salmonella adhesion activity of Saccharomyces boulardii ; Effects of of Ginkgo biloba on activities of Cytochromes P-450 /

Mohutsky, Michael A. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 207-232).
283

Biologinių ekstraktų, tinkamų Kolorado vabalo bulvių pasėliuose kontrolei, tyrimai / Researching of biological extracts for Colorado beetles in potatoes fields

Garbenis, Vaidotas 14 January 2009 (has links)
Darbo objektas – ekologiškai auginamos bulvės, kuriose pasireiškia kolorado vabalai. Darbo tikslas – įvertinti pušų ir gvazdikėlių ekstraktų poveikį kolorado vabalams bulvių pasėliuose. Darbo metodai – tyrimas buvo vykdomas 2007 m.. Bulvių sėkla daiginta 20 dienų šviesioje ir šiltoje patalpoje. Bandymas buvo įrengtas sodo sklypelyje. Pavasarį žemė įdirbta kastuvu. Mėšlas įterptas kastuvu 40 t ha-1 norma. Bulvių veislė „Rosela“. Pasodinta rankomis išmėtant bulves į padarytas vagutes. Bandymo bulvės buvo suskirstytos po dvi vagas purkšti ekstraktais, ir kontrolei. Purkšta pušų ir gvazdikėlių ekstraktų tirpalais. Dėl meteorologinių sąlygų (lietaus) bulvės jau buvo 10 – 15 cm kai pasirodė pirmieji kolorado vabalai. Po purškimų buvo stebima ar sumažėjo kolorado vabalų ir vertinama koks ekstraktas labiausiai paveikė kolorado vabalus. Nukasus bulves jų gumbai buvo sveriami. Nustatyta vidutinė vieno bulvių kero gumbų masė gramais, bei vidutinis gumbų skaičius vienetais. Purškiant buvo naudojami skydai, kad apsaugoti kitus variantus. Gumbų masė nustatyta svėrimo metodu. Purkštų pušų ir gvazdikėlių ekstraktų tirpalais bulvių derlius buvo lyginamas su kontroliniu variantu. Prieš pradedant vykdyti tyrimus, gegužės mėnesį buvo bandoma, kurią koncentraciją pasirinkti tolimesniams tyrimams (dėl vietos stokos ir bandymų vykdymo sudėtingumo). Preliminarūs tyrimai buvo atliekami dvejose vietose: Vokėje ir Šilalėje. Prieita nuomonės, kad 1% koncentracijos tirpalai mažai efektingi. Tuo tarpu... [toliau žr. visą tekstą] / Object of work – cultivation of ecologic potatoes, in which was found colorado beetles. Purpose of work – to estimate pine and clove extracts influence for pest (colorado beetles) into potatoes crops. Methods of work – the research had been conducting at 2007 y.. The seed of potatoes was cultivating in brightly and warm place for twenty days. The test was made in plot of garden. The soil was diged by spade on springtime. Manure was spread by spade 40 t. to hectare norm. The sort of potatoes „Rosela“. The potatoes was plant into furrows by hands. The researching potatoes was plant into to furrow, for sprinkling by extracts and for control. The potatoes was sprinkled by pine and clove extracts. Because of rain potatoes already was 10-15 cm. high, when appear first pests. After sprinkling was looking, if populiation of insects decrease, and testing which of extratcs was more effective. After potaoes gathering, it was weigh. Was find out a average weight of one potatoes growth bush, and average number of potatoes into bush. Was used screen to protect other rows of potato. The weight of lumps was found by weigh method. The harvest of sprinkled potatoes was compare with control rows. Before tests, was testing which concentration of extract to choose for research ( because of shortage of time, and complication of research). The research have been done in to place: Voke and Silale. I come to concliusion that 1% concentration extract aren‘t efective... [to full text]
284

Silosoujamų pašarų kokybės gerinimas, siekiant užtikrinti galvijų sveikatingumą / Silage feed quality improvement in order to maintain the cattle wellness

Grišiūtė, Sandra 05 March 2014 (has links)
Siekiant pagerinti silosuojamų pašarų kokybę ir užtikrinti galvijų sveikatingumą, buvo ištirtas kukurūzų siloso užterštumas, siloso mėginiai paimti iš įvairių Lietuvos vietovių ir įvertintas užterštumas mikroormanizmais ir mikromicetais. Nustatytas mikromicetų jautrumas Vaistinio čiobrelio (Thymus vulgaris), Vaistinio šalavijo (Salvia officinalis) ir Paprastojo raudonėlio ( Origanum vulgare) 100% eteriniams aliejams. Užkonservavus kukurūzų siloso žaliavą laboratorinėmis sąlygomis, po 96 dienų buvo nustatytas eterinių aliejų antigrybinis ir antibakterinis veikimas minėtiems eterininiams aliejams 1:100, 1:200 koncentracijų, Vaistinio čiobrelio ir Vaistinės juozažolės, ekstraktams ir žolelėms. Nustatytos trichotecenų (T–2), deoksinivalenolo (DON), zearalenono (ZON) ir aflatoksino B1 (AFL B1), mikotoksinų koncentracijos Vaistinio čiobrelio, Vaistinės juozažolės, Vaistinio šalavijo ir Paprastojo raudonėlio eterinių aliejų 1:200 koncentracijojose. / In order to assess contamination of corn silage, it´s examples were taken from diffrent locations of Lithuania and established their contamination of microorganisms. Established the sensitivity of fungi for Thyme (Thymus vulgaris), Hyssop (Hyssopus officinalis) ), Salvia (Salvia officinalis), and Oregano (Origanum vulgare), 100% essential oils. In fermented raw corn silage on laboratory conditions after 96 days were established antibacterial and antifungal activity of essential oils in 1:100 and 1:200 concentations, Thyme and Hyssop extraxts and herbs.In mentioned essential ois 1:200 concentrations were established T–2 toksinas, deoxynivalenol ( DON) , zearalenone ( ZON ) and aflatoxin B1 ( AFL B1) mycotoxins concentrations.
285

Vaistinių melisų ištraukų technologija ir kokybės vertinimas / The analysis of quality and technology of extracts of Melissa officinalis

Raišytė, Toma 01 July 2014 (has links)
Darbo tikslas: Pagaminti vaistinių melisų ištraukas ir įvertinti jų kokybę. Darbo uždaviniai: 1. Remiantis mokslinės literatūros duomenimis parinkti tinkamą vaistinių melisų skystą vaisto formą, atsižvelgiant į veikliosios medžiagos farmakologines savybes bei parinkti analizės metodus preparatų kokybei įvertinti; 2. Nustatyti ekstrahento (etanolio ir vandens) įtaką melisų ištraukų kokybei; 3. Palyginti ekstrahavimo metodo daromą įtaką vaistinių melisų ištraukų kokybei; 4. Ištirti žaliavos ir ekstrahento santykio daromą įtaką vaistinių melisų ištraukų kokybei. Metodika: 1. Tyrimo objektas – vaistinių melisų ištraukos; 2. Vaistinių melisų vandeninių ir etanolinių ištraukų technologija: a) Ištraukos gamintos klasikinės maceracijos ir perkoliacijos metodais; b) Etanolinės ištraukos gamintos ekstrahuojant ultragarsu ir kokybė vertinama po 20 min., 30 min. ir 40 min. ekstrahavimo; 3. Taikytas spektrofotometrinis metodas pagal Folin – Ciocalteau metodiką, norint nustatyti suminį polifenolinių junginių kiekį pagal KRE; 4. Sauso likučio tyrimas atliktas gravimetriniu metodu; 5. Antimikrobinis aktyvumas nustatytas pagal Ph. Eu. 01/2002, 2.6.12 metodiką. Rezultatai: Spektrofotometriniu metodu nustatyta, kad ekstrahentas turi įtakos veikliųjų junginių išsiskyrimui: didesnis suminis polifenolinių junginių bei sauso likučio kiekis nustatytas, kai ekstrahentu pasirenkamas etanolis, o ne vanduo. Vertinant etanolio koncentraciją nustatyta, kad mažiausiai veikliųjų junginių... [toliau žr. visą tekstą] / Purpose of work: To make and evaluate the quality of Melissa officinalis extracts. Tasks of work: 1. According to the scientific literature to identify an appropriate Balm liquid dosage form according to the pharmacological properties of the active material and the selection of analytical methods for evaluating the quality of products; 2. To set an extraction solvent (ethanol and water) influence on the quality of extracts of Melissa officinalis; 3. To compare extraction method influence on the quality of extracts of Melissa officinalis; 4. To investigate the relationship between the raw material and extraction solvent influence on the quality of extracts of Melissa officinalis. Methods: 1. Object of analysis – extracts of Melissa officinalis; 2. Preparation of an aquous and ethanolic extracts: a) Extracts have been produced by tradicional maceration and percolation methods; b) Ethanol extracts have been produced by extraction by ultrasound. The quality of these extracts has been evaluated after 20, 30, 40 min. 3. Spectrophotometric method (Folin – Ciocalteua method) – common amount of total polyphenolic compounds by p-cumaric acid equivalent has been evaluated; 4. The evaluation of dry residual according to gravimetric analysis has been calculated; 5. Antimicrobial activity by Ph. Eu. 01/2002, 2.6.12 method has been evaluated. Results: By spectrophotometric method it has been evaluated that extrahent has the influence on active compounds emission: higher amount of... [to full text]
286

Untersuchung von Extraktstoffen aus thermisch modifizierter Rotbuche (Fagus sylvatica L.) auf ihre fungizide Wirkung / Investigation of extract materials from thermally modified beech (Fagus sylvatica L.) on their fungicidal effect

Pfriem, Alexander, Horbens, Melanie, Beyer, Mario, Peters, Jana 12 August 2010 (has links) (PDF)
Bestimmte Extraktstoffe aus thermisch modifizierter Buche weisen fungizide Eigenschaften auf. Methanol-Extrakte aus thermisch modifizierter Buche, die in Propanon wieder aufgelöst wurden, wiesen eine leichte pilzwachstumshemmende Wirkung auf. Die getränkten Prüfkörper aus Buche erreichten eine Zuordnung zur Dauerhaftigkeitsklasse 4, d. h. nicht dauerhaft. Prüfkörper, die mit anderen Extrakten aus thermisch modifizierter Buche getränkt wurden, dabei insbesondere Wasser-Extrakte, weisen dagegen keine signifikante Resistenzverbesserung auf. Die Analyse der Methanol-Extrakte mittels Gaschromatografie mit Massenspektrometrie-Kopplung (GC-MS) ließ einen erhöhten Anteil bestimmter phenolischer Verbindungen erkennen, die teilweise Resistenz fördernde Wirkungen haben. Das Vorhandensein dieser Verbindungen kann somit als Begründung der Verbesserung der Resistenz entsprechend imprägnierter Prüfkörper herangezogen werden. Die Endfassung des Artikels ist auf www.holztechnologie.de verfügbar. / Certain extractives from thermally modified beech have fungicidal properties. Methanol extracts, resolubilized in propanone, caused a significant retardation of fungal growth on native beech specimen. Beech specimen impregnated with these extractives could be assigned to the durability class 4, i. e. not permanent. Other extracts of thermally modified beech, in particular water extracts, did not show significant improvement in resistance. The analysis of methanol extracts using gas chromatography coupled with mass spectrometry (GC-MS) showed an increased amount of phenolic compounds known to increase resistance. Their presence in organic extracts of thermally modified wood may explain the improvement of the resistance of the impregnated specimen. The original publication is available at www.holztechnologie.de.
287

The screening of anti-inflammatory action of Clinacanthus nutans (Burm. f.) Lindau : a critical evaluation of carrageenan-induced hind paw edema model /

Wipa Tanasomwang, Jutamaad Satayavivad, January 1986 (has links) (PDF)
Thesis (M.Sc. (Pharmacology))--Mahidol University, 1986.
288

Leaching of active ingredients from blueberries and cranberries using supercritical carbon dioxide and ethanol as an entrainer and analyzing using GC/MS

Elsayed, Nada H. January 2009 (has links)
Thesis (M.S.B.E.)--University of South Florida, 2009. / Title from PDF of title page. Document formatted into pages; contains 108 pages. Includes bibliographical references.
289

Estudo da atividade antimicrobiana de algumas árvores medicinais nativas com potencial de conservação/recuperação de florestas tropicais

Gonçalves, Airton Luiz [UNESP] 17 December 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-12-17Bitstream added on 2014-06-13T20:04:37Z : No. of bitstreams: 1 goncalves_al_dr_rcla.pdf: 945914 bytes, checksum: fce356cecae2c1fe9d88e10c5964e809 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este estudo avaliou a atividade antimicrobiana (AA) de extratos hidroalcoólicos, obtidos de diferentes órgãos de 43 espécies de árvores medicinais nativas do Brasil, frente a 10 microrganismos isolados de focos de infecções clínicas (IFI) e 4 microrganismos de referência catalogados na American Type Culture Collection-EUA (ATCC), analisando-se assim, além do potencial antimicrobiano destas plantas, as futuras perspectivas que estas árvores nativas oferecem ao serem utilizadas em projetos de extrativismo auto-sustentável (conservação) e projetos de recuperação de áreas degradadas (reflorestamento) em florestas tropicais. Para os ensaios de antibiose, foi utilizado o método da difusão em ágar, utilizando discos (BAUER et al., 1966). Dos 602 (100%) testes realizados, 31 (5,2%) mostraram halo de inibição Intermediário (I) e 84 (14%) dos testes, mostraram AA, com halo de inibição Sensível (S), destacando-se os extratos de: Bixa orellana e Mimosa tenuiflora frente à [Streptococcus pyogenes, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus (IFI) e Staphylococcus aureus (ATCC)]; Vernonia polyanthes frente à [Streptococcus pyogenes, Staphylococcus aureus, Staphylococcus spp coagulase negativa (IFI) e Staphylococcus aureus e Salmonella typhimurium (ATCC)]; Psidium guajava frente à [Streptococcus pyogenes, Proteus mirabilis, Staphylococcus aureus (IFI), e Staphylococcus aureus, Staphylococcus epidermidis e Salmonella typhimurium (ATCC)]; Anacardium occidentale frente à [Proteus mirabilis, Shigella flexneri, Staphylococcus aureus (IFI), Staphylococcus aureus e Salmonella typhimurium (ATCC)]; Stryphnodendron adstringens frente à [Streptococcus pyogenes, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus, Staphylococcus spp coagulase negativa (IFI), e Staphylococcus aureus e Staphylococcus epidermidis (ATCC)]. Foi observado maior destaque da AA, com o extrato hidroalcoólico de Eugenia uniflora frente a... / This study evaluated the antimicrobial activities (AA) of hydroalcoholic extracts obtained from different parts of 43 species of native Brazilian medicinal trees, against 10 different microorganisms isolated from clinically infected spots (IFI) and 4 microorganisms from American Type Culture Collection-EUA (ATCC), analysing in a manner, beyond of antimicrobial potency of this plants, the future perspectives which this native trees offerer, when will be utilized in a projects of auto-sustainable extrative (conservation) and in a projects of recuperation in degraded areas (reforestation) in tropical forest. The agar diffusion method was used, utilizing discs for antibiosis assay purposes (BAUER et al., 1966). Of the 602 (100%) tested carried out, 31 (5,2%) exhibited Intermediary inhibition halo (I); and 84 (14%) exhibited Sensitive inhibition halo (S) showing the most outstanding extracts qualities: Bixa orellana and Mimosa tenuiflora against [Streptococcus pyogenes, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus (IFI) and Staphylococcus aureus (ATCC)]; Vernonia polyanthes against [Streptococcus pyogenes, Staphylococcus aureus, Staphylococcus spp negative coagulase (IFI) and Staphylococcus aureus and Salmonella typhimurium (ATCC)]; Psidium guajava against [Streptococcus pyogenes, Proteus mirabilis, Staphylococcus aureus (IFI), and Staphylococcus aureus, Staphylococcus epidermidis and Salmonella typhimurium (ATCC)]; Stryphnodendron adstringens against [Streptococcus pyogenes, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus, Staphylococcus spp negative coagulase (IFI), and Staphylococcus aureus and Staphylococcus epidermidis (ATCC)]. Prominence of AA was observed with the extract of Eugenia uniflora against [Escherichia coli, Streptococcus pyogenes, Proteus mirabilis, Shigella flexneri, Staphylococcus aureus, Staphylococcus spp negative coagulase (IFI), and Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis
290

Fitoterápicos padronizados para o tratamento de doenças crônicas : Rhizophora mangle /

Mesquita, Leonardo Mendes de Souza. January 2017 (has links)
Orientador: Wagner Vilegas / Resumo: As espécies vegetais contendo substâncias bioativas são, cada vez mais, objeto de pesquisas, levando a alternativas para tratamentos terapêuticos ou revelando substâncias que posteriormente possam ser exploradas com o intuito de produzir fármacos. Estudos de plantas são de grande importância, em razão do vasto número de metabólitos secundários que podem ser encontrados. Eles têm cada vez mais atraído a atenção da sociedade, mostrando-se uma fonte alternativa aos altos custos dos medicamentos alopáticos. Mas, para que as plantas sejam usadas com eficácia e segurança, são necessários estudos multidisciplinares. A Agência Nacional de Vigilância Sanitária e o Ministério da Saúde aprovaram o uso de 71 plantas medicinais no tratamento contra diabetes, úlceras, inflamações e outras doenças crônicas. Contudo, essa é uma lista ainda limitada, pois várias espécies não são disponíveis o ano todo e/ou nas várias regiões do Brasil. Em contrapartida, Rhizophora mangle (Rhizophoraceae, popularmente conhecida como mangue vermelho) é uma espécie que ocorre no Brasil desde o Pará até Santa Catarina. É comumente utilizada pelas populações tradicionais costeiras, principalmente para o tratamento de diabetes, hemorroidas, analgesia e dores estomacais. Recentemente, nosso grupo de pesquisa verificou que o extrato acetônico das cascas de R. mangle possui atividades antioxidante e antiulcerogênica, e é eficaz no tratamento da colite experimental. Contudo, foi realizada apenas uma avaliação prelimina... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Plant species containing bioactive compounds are continuously being investigated, in order to search for alternative therapeutic treatments. These studies can reveal substances that can be explored in order to produce new drugs. Investigation of plants are of great importance, because of the large amounts of secondary metabolites that can be found. They have increasingly attracted the attention of the society, proving to be an alternative source to the high costs of allopathic medicines. However, multidisciplinary studies are necessary to ensure that plants are used with effectively and safety. The National Sanitary Surveillance Agency and the Ministry of Health have approved 71 medicinal plants to be used against diabetes, ulcers, inflammation and other chronic diseases. However, this list is still limited because several species are not available year-round and/or in the various regions of Brazil. In contrast, Rhizophora mangle (Rhizophoraceae, popularly known as red mangrove) is a Brazilian species that occurs from Pará to Santa Catarina. It is commonly used by traditional coastal populations, mainly for the treatment of diabetes, hemorrhoids, analgesia and stomach pains. Recently, our research group verified that the acetone extract of R. mangle barks has antioxidant and antiulcerogenic activities and it is also effective in the treatment of the experimental colitis. However, only a preliminary evaluation of the chemical composition of the barks was previously carried out... (Complete abstract click electronic access below) / Mestre

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