Letteratura scientifica selezionata sul tema "Microbiological screening"
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Articoli di riviste sul tema "Microbiological screening"
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Dow. "'Noise' in microbiological screening assays". Transfusion Medicine 10, n. 2 (giugno 2000): 97–106. http://dx.doi.org/10.1046/j.1365-3148.2000.00248.x.
Testo completo
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Barbara, John A. J., e Marcela Contreras. "7 Microbiological screening of blood donations". Baillière's Clinical Haematology 3, n. 2 (aprile 1990): 339–54. http://dx.doi.org/10.1016/s0950-3536(05)80054-x.
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Petrovic, Jelena, Brankica Kartalovic, Radomir Ratajac, Jasna Prodanov-Radulovic, Igor Stojanov, Marina Zekic e Srdjan Stefanovic. "Detection of enrofloxacine residues by microbiological screening method". Biotehnologija u stocarstvu 35, n. 1 (2019): 49–59. http://dx.doi.org/10.2298/bah1901049p.
Testo completoAbstract (sommario):
The usage of microbiological screening tests is widespread in control of presence of antimicrobial drug residues in meat samples. Screening tests must be capable to detect antimicrobial drug residue of interest and detection limits must comply with MRL (Maximum Residue Limit). The aim of this study was to examine the performance of a microbiological screening test with E. coli as test microorganism: capability of detecting enrofloxacina and it?s main metabolite ciprofloxacine at MRL levels in both fortified and incurred chicken tissue samples. Detection limits of microbiological screening test with E. coli was 50 ng/g for enrofloxacin and 25 ng/g for ciprofloxacin. Screening test had positive results in all samples of fortified and incurred meat with residue concentrations above MRL level. The results of this examinations shows that microbiological screening test with E. coli, as simple and cost effective test, is capable to detect enrofloxacine and it?s metabolite ciprofloxacine in treated poultry at MRL level ie test is capable to detect unsafe poultry meat.
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Prax, Marcel, Isabelle Bekeredjian-Ding e Oleg Krut. "Microbiological Screening of Platelet Concentrates in Europe". Transfusion Medicine and Hemotherapy 46, n. 2 (2019): 76–86. http://dx.doi.org/10.1159/000499349.
Testo completo
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Kochansky, Jan, Mark F. Feldlaufer e I. Barton Smith. "Microbiological screening assay for tylosin in pollen". Journal of Apicultural Research 45, n. 2 (gennaio 2006): 37–41. http://dx.doi.org/10.1080/00218839.2006.11101323.
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Stray-Pedersen, Babill, J. Biørnstad, Liv Kristiansen, Kirsti Hansen, T. Bergan, Marianne Dahl e G. Aanestad. "Induced abortion: Microbiological screening and medical complications". Infection 19, n. 5 (settembre 1991): 305–8. http://dx.doi.org/10.1007/bf01645352.
Testo completo
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Pawlak, Maria, Katarzyna Lewtak e Aneta Nitsch-Osuch. "Effectiveness of Antiepidemic Measures Aimed to Reduce Carbapenemase-Producing Enterobacteriaceae in the Hospital Environment". Canadian Journal of Infectious Diseases and Medical Microbiology 2022 (26 aprile 2022): 1–7. http://dx.doi.org/10.1155/2022/9299258.
Testo completoAbstract (sommario):
Purpose. The objective of this study was to evaluate the effectiveness of hospital-based antiepidemic measures aimed at limiting the spread of symptomatic infections and colonization with carbapenem-resistant Enterobacteriaceae (CPE), mainly NDM-producing Klebsiella pneumoniae, with particular emphasis on microbiological screening tests. Methods. This retrospective study was based on data from 168 hospitals under the supervision of the Provincial Sanitary and Epidemiological Station in Warsaw, Poland, in 2016–2017. Analysis of the effectiveness of antiepidemic procedures focused on the type of implemented antiepidemic procedures, the number of microbiological screening tests per year, the geographic location of the hospitals (inside or outside Warsaw), the timing of the screening tests (on admission to hospital or 48 hours later), and the results of the screening tests. Results. Rates of proper isolation of patients infected or colonized with an alarm pathogen including NDM-producing K. pneumoniae increased from 38.0% in 2016 to 49.5% in 2017 ( p > 0.05 ). The number of screening tests performed increased by 88% from 68319 in 2016 to 128373 in 2017. The number of epidemic outbreaks of symptomatic infections caused by NDM-producing K. pneumoniae decreased from 11 in 2016 to 7 in 2017 in hospitals in Warsaw, where microbiological screening tests were performed. The number of outbreaks in hospitals outside Warsaw, where the screening tests were not performed or were limited, increased from 8 in 2016 to 24 in 2017. Conclusion. Screening tests increase the chance of detecting colonization by CPE. The implementation of microbiological screening decreased the risk of epidemic outbreaks of symptomatic infections caused by CPE.
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Tannus, Hugo, F. Mendonca-Filho, Daniel A. Vieira, Erika W. Pinheiro, Viegas N. Monica, Marisa Santos, Pedro M. Nogueira, Marco Aurelio e O. Fernandes. "CYTOKINE PROFILE AND MICROBIOLOGICAL SCREENING IN POSTOPERATIVE SEPSIS". Critical Care Medicine 32, Supplement (dicembre 2004): A150. http://dx.doi.org/10.1097/00003246-200412001-00535.
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Fitch, Marjorie E., A. Reed Mangels, Wendy A. Altmann, Mohammed El Hawary, Asaf A. Qureshi e Charles E. Elson. "Microbiological screening of mevalonate-suppressive minor plant constituents". Journal of Agricultural and Food Chemistry 37, n. 3 (maggio 1989): 687–91. http://dx.doi.org/10.1021/jf00087a024.
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Van Der Zee, Henk, e Jos H. J. Huis In T Veld. "Rapid and Alternative Screening Methods for Microbiological Analysis". Journal of AOAC INTERNATIONAL 80, n. 4 (1 luglio 1997): 934–40. http://dx.doi.org/10.1093/jaoac/80.4.934.
Testo completoAbstract (sommario):
Abstract Automated analytical instruments for enumerating indicator organisms and diagnostic test kits for pathogens can be used in food microbiology to screen samples and to replace conventional cultural and confirmation steps. Such methods are now available for rapid detection or estimation of groups of (indicator) organisms, pathogenic microorganisms, bacterial toxins and mycotoxins, and molds. These alternative methods can be classified by the principles on which they are based: modified conventional methods, instrumental measurement of bacterial metabolism, bioluminescence, immunological techniques, DNA techniques, and combinations of these techniques. To meet user expectations, test kits must be accurate, sensitive, specific, rapid (24 h or less), easy to use, and laborsaving. They must also offer the possibility of computerization, a low detection limit, and low investment and running costs. The paper compares the ability of alternative methods to meet these criteria. Variations were found, depending on the techniques used and the target organism of the analysis. Economic reasons can determine whether alternative methods can be used routinely. Adoption of these screening systems also can be hampered by lack of internationally coordinated and accepted validation protocols.
Tesi sul tema "Microbiological screening"
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Vasou, Andri. "Development of a novel cell-based screening platform to identify inhibitors of viral interferon antagonists from clinically important viruses". Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/8266.
Testo completoAbstract (sommario):
All viruses encode for at least one viral interferon (IFN) antagonist, which is used to subvert the cellular IFN response, a powerful antiviral innate immune response. Numerous in vitro and in vivo studies have demonstrated that IFN antagonism is crucial for virus survival, suggesting that viral IFN antagonists could represent promising therapeutic targets. This study focuses on Respiratory Syncytial Virus (RSV), an important human pathogen for which there is no vaccine or virus-specific antiviral drug. RSV encodes two IFN antagonists NS1 and NS2, which play a critical role in RSV replication and pathogenicity. We developed a high-throughput screening (HTS) assay to target NS2 via our A549.pr(ISRE)GFP-RSV/NS2 cell-line, which contains a GFP gene under the control of an IFN-stimulated response element (ISRE) to monitor IFN- signalling pathway. NS2 inhibits the IFN-signalling pathway and hence GFP expression in the A549.pr(ISRE)GFP-RSV/NS2 cell-line by mediating STAT2 degradation. Using a HTS approach, we screened 16,000 compounds to identify small molecules that inhibit NS2 function and therefore relinquish the NS2 imposed block to IFN-signalling, leading to restoration of GFP expression. A total of twenty-eight hits were identified; elimination of false positives left eight hits, four of which (AV-14, -16, -18, -19) are the most promising. These four hit compounds have EC₅₀ values in the single μM range and three of them (AV-14, -16, -18) represent a chemically related series with an indole structure. We demonstrated that the hit compounds specifically inhibit the STAT2 degradation function of NS2, not the function of NS1 or unrelated viral IFN antagonists. At the current time, compounds do not restrict RSV replication in vitro, hence hit optimization is required to improve their potency. Nonetheless, these compounds could be used as chemical tools to determine the unknown mechanism by which NS2 mediates STAT2 degradation and tackle fundamental questions about RSV biology.
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Rizzotto, Francesco. "Approches innovantes pour la préservation et la sécurité des aliments : développement de l'emballage actif et dépistage microbiologique avancé". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASB036.
Testo completoAbstract (sommario):
La conservation et la sécurité des aliments font partie des préoccupations majeures du secteur agroalimentaire. Le gaspillage alimentaire, dû à la détérioration et à la contamination microbienne, a un fort impact économique. De plus, les agents pathogènes d'origine alimentaire posent un risque sérieux pour la santé des consommateurs. Les techniques conventionnelles de conservation des aliments et d'analyse microbienne présentent des limites qui nécessitent d'innovation. Cette thèse a pour objectif de développer des solutions pratiques et durables pour améliorer la qualité et la sécurité des aliments. Les nanoparticules (NPs) métalliques et d'oxyde métallique sont des matériaux polyvalents, en raison de leurs propriétés uniques, telles que leurs activités antioxydantes, antimicrobiennes, optiques et catalytiques. Ils peuvent être ajoutés aux films d'emballage pour inhiber la croissance microbienne et prolonger la conservation des aliments. Dans cette étude, des NPs ont été développées en dopant le TiO2 avec du fer. Les NPs Fe2TiO5 obtenues n'ont pas été trouvées cytotoxiques, comme démontré sur les cellules Caco-2. De plus, il n'y avait pas de migration d'ions de fer ou de titane vers des simulants alimentaires des films incorporant Fe2TiO5 dans de l'alginate. Ceci suggère leur sécurité en tant que matériau d'emballage. Une forte efficacité antioxydante a également été montrée par les Fe2TiO5, confirmée par un test de conservation des fruits frais avec le film d'alginate contenant les Fe2TiO5. L'alginate, matériau biodégradable, offre une alternative aux plastiques pétroliers, favorisant une préservation alimentaire durable.Deux solutions différentes ont été étudiées pour développer de nouveaux tests de dépistage des pathogènes alimentaires. La première consistait en un test colorimétrique pour détecter les spores de B. cytotoxicus, qui posent un risque sérieux pour les consommateurs, en raison de leur résistance aux traitements lors de la production industrielle. Le principe de détection repose sur l'activité catalytique des nanoparticules d'or (AuNPs) similaire à celle de la peroxydase, amplifiée par les spores. La plateforme de détection comprend un microtube contenant des AuNPs et des particules magnétiques (MPs), toutes deux conjuguées avec un aptamère sélectionné pour sa spécificité envers les spores de B. cytotoxicus. Lors de l'ajout de l'échantillon, la présence des spores est déterminée par le changement de couleur accru de la solution, dû à l'oxydation de la tétraméthylbenzidine en présence de H2O2. Le test développé a permis une détection à l'œil nu, rapide et spécifique, des spores cibles directement dans les denrées alimentaires telles que le lait ou la purée de pommes de terre. Le deuxième test consistait en un génocapteur électrochimique pour détecter Campylobacter, la cause la plus fréquente de zoonose d'origine alimentaire. La détection était basée sur l'hybridation entre une séquence d'ADN de Campylobacter avec une sonde ADN complémentaire, immobilisée sur une électrode en or sérigraphiée. Une passivation avec du mercaptohexanol a été réalisée pour réduire les phénomènes d'adsorption des molécules d'ADN sur l'électrode, et éviter les signaux non spécifiques. L'étude présentait des capacités prometteuses de détection. Cependant, des défis concernant la passivation de la surface et la stabilité du signal de détection, soulignant la nécessité d'optimisations supplémentaires. Dans l'ensemble, la thèse vise à améliorer la qualité et la sécurité des aliments, contribuer à un système alimentaire plus durable et stimuler la recherche et le développement technologiqueFood conservation and safety are major concerns in the agri-food sector. Food lost and waste, due to deterioration and microbial contamination, have a significant economic impact. Additionally, foodborne pathogens pose serious health risks to consumers. Conventional methods for food preservation and microbial analysis have limitations that urgently require innovation. This thesis aims to develop practical and sustainable solutions to enhance food quality and safety. Metallic and metal oxide nanoparticles (NPs) are versatile materials known for their unique properties such as antioxidant, antimicrobial, optical, and catalytic activities. They can be incorporated into packaging films to inhibit microbial growth and extend food shelf life. In this study, NPs were developed by doping TiO2 with iron to obtain Fe2TiO5 NPs, which were found non- cytotoxic as demonstrated on Caco-2 cells. Furthermore, films incorporating Fe2TiO5 into alginate showednomigrationofironortitaniumionsintofood simulants, suggesting their safety as packaging materials. Fe2TiO5 also exhibited strong antioxidant efficacy, confirmed by a fresh fruit preservation test using alginate films containing Fe2TiO5. Alginate, a biodegradable material, offers an alternative to petroleum-based plastics, promoting sustainable food preservation. Two different solutions were studied to develop new methodologies for detecting foodborne pathogens. The first involved a colorimetric test to detect B. cytotoxicus spores, which pose a serious risk due to their resistance to industrial treatments. The detection principle is based on the peroxidase-like catalytic activity of gold nanoparticles (AuNPs) enhanced by the spores. The detection platform consists of a tube containing AuNPs and magnetic particles, both conjugated with an aptamer selected for its specificity towards B. cytotoxicus spores. Upon addition of the sample, the presence of spores is indicated by an increased color change of the solution, due to the oxidation of tetramethylbenzidine (TMB) in the presence of H2O2. The developed test enabled rapid and specific naked-eye detection of target spores directly in food items such as milk or mashed potatoes. The second test involved an electrochemical genosensor to detect Campylobacter, the most common cause of foodborne zoonoses. Detection was based on hybridization between a Campylobacter DNA sequence and a complementary DNA probe immobilized on a screen-printed gold electrode. After DNA probe immobilization, passivation with mercaptohexanol was carried out to reduce DNA molecule adsorptionphenomenaontheelectrodeandavoid nonspecific signals The study demonstrated promising detection capabilities. However, challenges regarding surface passivation and detection signal stability underscored the need for further optimizations. Overall, the thesis aims to improve food quality and safety, contribute to a more sustainable food system, and stimulate technological research and development
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De, Pascali Alessandra Mistral <1993>. "Leishmaniasis in the immunocompromised population: evaluation of strategies for screening and monitoring". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/10004/1/Thesis%20PhDfinal.pdf.
Testo completoAbstract (sommario):
Leishmaniasis is a vector-borne disease caused by an intracellular parasite of the genus Leishmania.
The clinical features of leishmaniasis include a wide range of manifestation from asymptomatic infections to different levels of disease severity.
In most cases individuals do not develop clinical symptoms, but Leishmania parasites can persist lifelong in the host after an acute infection and easily reactivate under immunosuppressive conditions, causing severe disease with high mortality rate.
The aim of this study was to identify Leishmania infection in selected groups of immunocompromised (IC) patients, including newly diagnosed HIV infected individuals, patients receiving kidney transplant (KT) and patients undergoing immunosuppressive therapies for immune-mediated diseases (IMD). Our study focused on the validation of a combination of methods to be used for the screening of asymptomatic Leishmania infection. The selected methods included high sensitive Real-Time PCR for detection of parasitic kinetoplast (k)DNA in peripheral blood, Western Blot (WB) for detection of specific IgG and Whole Blood Assay (WBA) to evaluate the anti-leishmanial T-cell response by quantifying the production of IFN-γ, IL-2 and IP-10 after stimulation of patients’ blood with Leishmania specific antigens.
The methods have been validated on a cohort of immunocompetent individuals living in an endemic area of the Bologna province. Among 145 individuals recruited and screened with WB, Real-Time PCR and WBA, 24 subjects tested positive (17%) to one or more methods, thus confirming the high circulation of the parasite in the selected area.
Given the high prevalence of asymptomatic infection in immunocompromised patients in endemic regions such as Italy, it seems essential to develop a plan for screening and follow-up of Leishmania infection. The screening algorithm that we tested in this study appears to be effective to identify accurately quiescent parasitic infection.
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Churro, Catarina Isabel Prata Pereira Leitão. "Natural algicides against harmful microalgae: screening the bacillamide potential as a prevention tool for cyanobacteria blooms". Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/755.
Testo completoAbstract (sommario):
Mestrado em MicrobiologiaO desenvolvimento de florescências de microalgas e de cianobactérias em ambientes aquáticos, marinhos e de água doce, pode ter consequências nefastas para os ecossistemas e para a saúde animal e humana. A prevenção e o combate à formação destas florescências envolve frequentemente a aplicação de agentes químicos com propriedades algicidas. Contudo, estes agentes são, na sua generalidade, inespecíficos, actuando não apenas sobre os organismos alvo mas também sobre a restante comunidade fitoplanctónica. A bacillamida é um composto natural recentemente isolado a partir de uma bactéria associada ao declínio de florescências de dinoflagelados marinhos. A sua toxicidade natural contra estas microalgas, associada a um baixo custo de produção em laboratório, apontam para a possível utilização deste composto como agente algicida no combate a proliferações algais nocivas. Neste trabalho avaliou-se o efeito da bacilamida e de um conjunto de compostos análogos no crescimento de diferentes estirpes de cianobactérias e de microalgas em cultura, com o objectivo de testar a aplicabilidade destes compostos na prevenção e no combate ao desenvolvimento de florescências. As culturas, inoculadas em microplacas de 96 pocetos, foram expostas a uma série crescente de concentrações de cada um dos compostos testados e incubadas numa câmara de culturas durante 216h. O crescimento algal foi seguido ao longo do período de incubação através da medição diária da densidade óptica (450nm) nos pocetos. As percentagens de inibição do crescimento foram calculadas a partir das curvas de crescimento obtidas em cada condição e as concentrações inibitórias IC50-216h foram calculadas por regressão das curvas de inibição através de análise de probits. A selectividade na acção tóxica de cada um dos compostos testados para as diferentes espécies foi estimada por comparação das concentrações inibitórias IC50- 216h obtidas nas diferentes culturas. Para além dos efeitos no crescimento, os efeitos na morfologia e ultrastrutura foram analisados por observação das células expostas ao microscópio óptico e ao microscópio electrónico de transmissão. Os resultados obtidos revelaram que as cianobactérias tóxicas Microcystis aeruginosa, Aphanizomenon gracile, Anabaena circinalis e Anabaenopsis circularis são mais susceptíveis à bacilamida do que as algas verdes Ankistrodesmus falcatus e Scenedesmus obliquus. Assim, um tratamento com bacilamida a 80µg.L-1 deverá afectar o crescimento destas cianobactérias sem afectar o desenvolvimento das algas verdes. Resumo Contudo, outras cianobactérias, tais como, Nodularia spumigena, Leptolyngbya sp. e Plankthotrix rubescens, exibiram níveis de tolerâncias à bacilamida semelhantes aos obtidos para a maioria das algas eucarióticas testadas. Resultados semelhantes foram obtidos com a bromobacilamida e a clorobacilamida. A metoxibacilamida, por seu lado, revelou-se particularmente tóxica para as cianobactérias Anabaena e Aphanizomenon (IC50-216h= 42 e 85 µg.L-1, respectivamente) em concentrações que não afectaram o crescimento de nenhuma das restantes culturas testadas. A fluorbacilamida e a iodobacilamida revelaram um espectro de acção tóxica mais amplo contra cianobactérias, afectando o crescimento destes organismos em concentrações mais baixas (IC50-216h = 20-40 µg.L-1) do que os restantes análogos testados. No entanto, a estas concentrações, estas bacilamidas afectaram também a maior parte das algas eucarióticas testadas, revelando-se portanto inespecíficas na sua acção tóxica. De todos os compostos testados, a triptamina (percursor da bacilamida) revelou ser o mais tóxico, afectando o crescimento da maioria das cianobactérias testadas em concentrações muito inferiores (IC50-216h = 1,1-4,1 µL-1) às necessárias para afectar o crescimento das clorófitas (IC50-216h = 6,9-10,2 µL-1). As diatomáceas foram contudo igualmente afectadas pela triptamina (IC50-216h = 0,5-2,5 µL-1) pelo que a sua aplicação em ambientes co-habitados por estes dois tipos de organismos fitoplanctónicos pode resultar em efeitos nocivos para ambos. Por outro lado a cianobactéria Planktothrix rubescens revelou-se bastante mais resistente à triptamina que as restantes cianobactérias testadas. As diferentes sensibilidades exibidas pelas diferentes culturas cianobacterianas a cada um dos compostos testados, demonstram que as bacilamidas e a triptamina não devem ser considerados algicidas de largo espectro contra cianobactérias. Contudo a aplicação de distintas bacilamidas no combate ao desenvolvimento de determinadas espécies cianobacterianas em particular, pode revelar-se eficaz desde que o tipo e concentração de bacilamida aplicada não afectem as restantes microalgas que compõem a comunidade fitoplactónica. A decisão sobre o tipo e quantidade de bacilamida a aplicar na prevenção do desenvolvimento de uma dada fluorescência deve portanto ter em conta não só a espécie cianobacteriana dominante mas também considerar a composição relativa de toda a comunidade fitoplanctónica, de modo a não afectar os organismos benéficos para o equilíbrio e produtividade do ecossistema.
Cyanobacterial blooms are of major concern to environmental and human health as they cause water deteoration and produces neuro and hepatotoxins. Bacillamide, a natural algicide produced by the marine bacteria Bacillus sp., and several newly synthesized analogues and also its precursors, were screened for selective antialgal activity against different cyanobacteria and eukaryotic algae. Its selective natural toxicity towards algal bloom-forming species and its possible low-cost synthetic production in the laboratory makes it one of the most promising compounds to pursue for use as a selective algicide against harmful algal blooms. A rapid 96-well microplate bioassay was used for screening selective antialgal activity of newly synthesized bacillamides and related compounds against different cyanobacterial and microalgal cultures. Aliquots of exponential growing stock cultures were inoculated in triplicate into the microplate wells previously filled with serial dilutions of each compound in the culture medium. The plates were steadily incubated in an algal culture chamber and daily optical measurements were used to estimate cultures growth over a 216h period. Inhibition values (%) were calculated from the estimated growth curves and inhibitory concentrations IC50-216h were obtained from the sigmoidal inhibition curves fitted by probit regression analysis. The effects of bacillamide and tryptamine on cell morphology and ultrastructure were also analysed by light and transmission electron microscopy. Results showed that the toxic cyanobacteria Microcystis aeruginosa, Aphanizomenon gracile, Anabaena circinalis and Anabaenopsis circularis were much more sensitive to bacilamide then the chlorophytes Ankistrodesmus falcatus and Scenedesmus obliquus. However, clear signs of morphological and ultrastructural changes induced by bacillamide could be observed on both cyanobacteria and chlorophytes. Other cyanobacteria, namely the Nostocales Nodularia spumigena and the Oscillatoriales Leptolyngbya sp. and Plankthotrix rubescens, exhibit higher tolerances to bacillamide, similar to the ones shown by different non-toxic algae. Thus, the use of bacillamide to control/remediate cyanobacterial blooms, should take into account the species composition in the phytoplankton community in order to avoid noxious effects on harmless phytoplankton. Among the other derivates tested, Fluor- and Chlorine-bacillamide showed similar results, while Metoxibacillamide seemed much less effective and Iodine-bacillamide strongly affected the growth of all the algae tested with no apparent selectivity. Concerning the bacillamide precursors, tryptamine showed much higher toxicity than bacillamides towards all the test organisms, while the 2-acethyl-1,3- thiazole-4-carboxyic acid had no growth effects on both the cyanobacteria and the microalgae screened.
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Santos, Cátia Raquel Talhas. "Screening of class 1 integrons in clinical isolates of Gram-negative bacteria". Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/8919.
Testo completoAbstract (sommario):
Mestrado em Microbiologia MolecularActualmente, é cada vez mais frequente a associação de bactérias oportunistas e comensais resistentes a antibióticos com infecções nosocomiais. Este problema clínico tornou-se preocupante e deve-se ao uso indiscriminado de antibióticos. Perante esta pressão selectiva, as bactérias desenvolvem diferentes mecanismos de resistência a estes compostos. A presença de estruturas capazes de transportar genes de resistência, designadas por integrões, que contribuem para a disseminação destes genes bem como a sua associação com o perfil de resistência de bactérias constitui o objectivo do presente trabalho. Assim, foram recolhidas amostras de superfícies das instalações sanitárias, do serviço de Medicina II, do Hospital Infante D. Pedro, Aveiro. Após o isolamento das bactérias em meio selectivo para Gramnegativas (MacKonkey), todos os isolados foram sujeitos a tipagem molecular por BOX-PCR. O perfil de bandas obtido após electroforese foi analisado com o programa GelCompar II software (Applied Maths, Kortrijk, Belgium), permitindo distinguir diferentes grupos clonais. De cada grupo clonal foi seleccionado um isolado para os estudos posteriores, resultando num total de 45 isolados distintos. A pesquisa de integrões classe 1 iniciou-se por um “screening” para o gene da integrase. Nos 25 isolados positivos para este gene, foi amplificada e caracterizada a respectiva região variável. A sequência nucleotídica dos amplicões foi comparada com outras depositadas na base de dados. Os resultados mostraram a presença de integrões em diferentes espécies (Pseudomonas putida, Klebsiella pneumoniae, Escherichia coli, Pseudomonas mendocina, Proteus mirabillis e Morganella morganii). As regiões variáveis apresentavam diferentes tamanhos e diferentes arranjos de genes. Em geral, predominam gene cassettes que conferem resistência aos aminoglicosídeos, trimetoprime e metalo-β- lactamases. A localização destas estruturas no genoma bacteriano foi efectuada por “southern blot”; o DNA genómico foi digerido com a enzima S1, e sujeito a hibridação com sondas para os genes 16S e da integrase revelando que a maioria dos integrões estão localizados em plasmídeos. Como conclusão geral, verifica-se a prevalência de isolados contendo determinantes genéticos de resistência em superfícies inanimadas do ambiente hospitalar (53.33%), os quais podem constituir um potencial risco para os pacientes, uma vez que se trata de bactérias oportunistas. O facto de estes genes de resistência estarem associados a elementos genéticos móveis, nomeadamente transposões e muitas vezes plasmídeos, facilita a sua disseminação no ambiente hospitalar, principalmente por transferência horizontal de genes.
Currently, it is becoming frequent the association of antibiotic resistant opportunistic and commensal bacteria with nosocomial infections. This is a clinical problem of concern and is based on the indiscriminate use of antibiotics. Given the selective pressure within the hospital environment, bacteria develop different resistance mechanisms to these compounds. The presence of structures, referred as integrons, that carry and disseminate these resistance genes among bacteria and their association with the bacteria resistance profile constitutes the aim of the present study. To this end we collected samples from surfaces of sanitary facilities, of the Medicine II service of the Hospital Infante D. Pedro, Aveiro. After bacteria isolation on a selective medium (MacKonkey) for Gram negatives, all the isolates were molecular typed by BOX-PCR. After electrophoresis, the banding pattern was analysed with the GelCompar II software (Applied Maths, Kortrijk, Belgium), which allowed for the selection of different clonal groups. One isolate was selected from each group for further studies. Forty five isolates were selected for the screening of class 1 integrons. In the twenty-five positive isolates respective variable region was amplified and characterized. Amplicons nucleotide sequences were compared with others deposited in databases. The results revealed the presence of integrons in different species (Pseudomonas putida, Klebsiella pneumoniae, Escherichia coli, Pseudomonas mendocina, Proteus mirabillis e Morganella morganii). Different lenghts of variable regions and different genes arrays were found. Generally gene cassettes conferring resistance to aminoglycosides trimethoprim and metallo-β-lactamases were predominante. Southern hybridization of S1 digested genomic DNA with 16 rDNA and integrase genes labeled probes revealed that the majority of the integrons are located in plasmids. To conclude, is important to refer that there is a prevalence of opportunistic bacteria possessing integrons in inanimate surfaces within the hospital environment, which can constitute risk to the debilitated patients. Moreover, these structures are associated with mobile genetic elements, mainly transposons and many times plasmids, which facilitates the dissemination of these antibiotic resistance genes in the hospital environment, mainly by horizontal gene transfer.
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Lopes, Érica de Oliveira [UNESP]. "Screening da atividade antiproliferativa e investigação toxicológica in vitro e in vivo de compostos de coordenação". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/132630.
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O câncer é um conjunto de doenças que têm em comum o crescimento celular desordenado que invade os tecidos e órgãos, podendo espalhar-se para outras regiões do corpo (metástase). Uma série de mudanças genéticas e epigenéticas, que são associadas ao DNA que influenciam a expressão genética, ocasionam o câncer. Nas últimas décadas, o câncer ganhou uma dimensão maior convertendo-se em um evidente problema de saúde pública mundial, sendo uma das principais causas de morte no mundo. O desenvolvimento de fármacos para o tratamento do câncer é possível de forma expressiva através da triagem de moléculas utilizando linhagens celulares tumorais ou métodos alternativos que reduzam o número de animais de experimentação. Em uma segunda etapa, ensaios in vivo em modelo convencional deverão garantir a segurança toxicológica e confirmar a biodisponibilidade da molécula. Desta forma, este estudo tem como objetivo, avaliar a atividade proliferativa frente às linhagens tumorais (HepG2, HeLa, MDA-MB-231, K-562, DU 145), o perfil mutagênico, a toxicidade em linhagem celular normal (MRC-5), pelo método alternativo (Artemia salina L.) e em camundongos BALB/c e a biodisponibilidade oral in vivo de compostos de coordenação (Mn, Co e Zn). Embora, todas as moléculas estudadas tenham apresentado efeito sobre as linhagens tumorais, os complexos de cobalto [Co(atc-Et)2]Cl e [Co(atc-Ph)2]Cl apresentaram os melhores Índices de Seletividade (IS). No ensaio de toxicidade aguda em Artemia salina L. apenas os três complexos [Mn(atc)2], [Mn(atc-Me)2] e [Co(atc-Ph)2]Cl se mostraram tóxicos para o microcustáceo, enquanto que na toxicidade aguda em camundongos apenas um complexo [Mn(atc-Me)2]. Os parâmetros bioquímicos analisados (enzimas ALT e AST), bem como o peso relativo dos órgãos dos animais, não mostraram diferença estatística significativa. No teste de Ames foi observado mutagenicidade apenas de três complexos de manganês...
Cancer is a group of diseases that have in common the uncontrolled cell growth that invades the tissues and organs and can spread to other parts of the body (metastasis). A number of genetic and epigenetic changes, that are associated with DNA and influence gene expression, cause cancer. In the last decades, cancer has gained a bigger dimension becoming an evident problem of global public health and is one of the leading cause of death worldwide. The development of drugs for the treatment of cancer is possible through screening of molecules using tumor cell lines or alternative methods that reduce the number of experimental animals. In a second step, in vivo assays in conventional model should ensure toxicological safety and confirm the bioavailability of the molecule. Thus, this study aims to evaluate the antiproliferative activity against the tumor cell lines (HepG2, HeLa, MDA-MB-231, K-562, DU 145), the mutagenic profile, toxicity in normal cell line (MRC-5) through the alternative method (Artemia salina L.) and BALB/c mice, and also, the coordination compound (Mn, Co and Zn) in vivo oral bioavailability. Although all the molecules studied have presented effect on tumor cell lines, and the cobalt complexes [Co(atc-Et)2]Cl and [Co(atc-Ph)2]Cl showed the best selectivity index (SI). In the acute toxicity test in Artemia salina L. only three complexes [Mn(atc)2], [Mn(atc-Me)2] and [Co(atc-Ph)2]Cl proved to be toxic to the microcrustacean, while that the acute toxicity in mice only one complex ([Mn(atc-Me)2]) presented toxic effect. Quantitative biochemical parameters (ALT and AST), as well as the relative weight of the organs of the animals showed no statistical difference. In the Ames test mutagenicity was observed only in three manganese complexes [Mn(atc-Me)2], [Mn(atc-Ch)2] and [Mn(atc-Ph)2]. As regards the quantification of the via ICP-OES oral bioavailability of plasma ...
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Lopes, Érica de Oliveira. "Screening da atividade antiproliferativa e investigação toxicológica in vitro e in vivo de compostos de coordenação /". Araraquara, 2015. http://hdl.handle.net/11449/132630.
Testo completoAbstract (sommario):
Orientador: Fernando Rogério PavanBanca: Victor Marcelo Deflon
Banca: Rosilene Fressatti Cardoso
Resumo: O câncer é um conjunto de doenças que têm em comum o crescimento celular desordenado que invade os tecidos e órgãos, podendo espalhar-se para outras regiões do corpo (metástase). Uma série de mudanças genéticas e epigenéticas, que são associadas ao DNA que influenciam a expressão genética, ocasionam o câncer. Nas últimas décadas, o câncer ganhou uma dimensão maior convertendo-se em um evidente problema de saúde pública mundial, sendo uma das principais causas de morte no mundo. O desenvolvimento de fármacos para o tratamento do câncer é possível de forma expressiva através da triagem de moléculas utilizando linhagens celulares tumorais ou métodos alternativos que reduzam o número de animais de experimentação. Em uma segunda etapa, ensaios in vivo em modelo convencional deverão garantir a segurança toxicológica e confirmar a biodisponibilidade da molécula. Desta forma, este estudo tem como objetivo, avaliar a atividade proliferativa frente às linhagens tumorais (HepG2, HeLa, MDA-MB-231, K-562, DU 145), o perfil mutagênico, a toxicidade em linhagem celular normal (MRC-5), pelo método alternativo (Artemia salina L.) e em camundongos BALB/c e a biodisponibilidade oral in vivo de compostos de coordenação (Mn, Co e Zn). Embora, todas as moléculas estudadas tenham apresentado efeito sobre as linhagens tumorais, os complexos de cobalto [Co(atc-Et)2]Cl e [Co(atc-Ph)2]Cl apresentaram os melhores Índices de Seletividade (IS). No ensaio de toxicidade aguda em Artemia salina L. apenas os três complexos [Mn(atc)2], [Mn(atc-Me)2] e [Co(atc-Ph)2]Cl se mostraram tóxicos para o microcustáceo, enquanto que na toxicidade aguda em camundongos apenas um complexo [Mn(atc-Me)2]. Os parâmetros bioquímicos analisados (enzimas ALT e AST), bem como o peso relativo dos órgãos dos animais, não mostraram diferença estatística significativa. No teste de Ames foi observado mutagenicidade apenas de três complexos de manganês...
Abstract: Cancer is a group of diseases that have in common the uncontrolled cell growth that invades the tissues and organs and can spread to other parts of the body (metastasis). A number of genetic and epigenetic changes, that are associated with DNA and influence gene expression, cause cancer. In the last decades, cancer has gained a bigger dimension becoming an evident problem of global public health and is one of the leading cause of death worldwide. The development of drugs for the treatment of cancer is possible through screening of molecules using tumor cell lines or alternative methods that reduce the number of experimental animals. In a second step, in vivo assays in conventional model should ensure toxicological safety and confirm the bioavailability of the molecule. Thus, this study aims to evaluate the antiproliferative activity against the tumor cell lines (HepG2, HeLa, MDA-MB-231, K-562, DU 145), the mutagenic profile, toxicity in normal cell line (MRC-5) through the alternative method (Artemia salina L.) and BALB/c mice, and also, the coordination compound (Mn, Co and Zn) in vivo oral bioavailability. Although all the molecules studied have presented effect on tumor cell lines, and the cobalt complexes [Co(atc-Et)2]Cl and [Co(atc-Ph)2]Cl showed the best selectivity index (SI). In the acute toxicity test in Artemia salina L. only three complexes [Mn(atc)2], [Mn(atc-Me)2] and [Co(atc-Ph)2]Cl proved to be toxic to the microcrustacean, while that the acute toxicity in mice only one complex ([Mn(atc-Me)2]) presented toxic effect. Quantitative biochemical parameters (ALT and AST), as well as the relative weight of the organs of the animals showed no statistical difference. In the Ames test mutagenicity was observed only in three manganese complexes [Mn(atc-Me)2], [Mn(atc-Ch)2] and [Mn(atc-Ph)2]. As regards the quantification of the via ICP-OES oral bioavailability of plasma ...
Mestre
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MELO, Liany Figuerêdo de Andrade. "Screening farmacológico e diversidade bacteriana do muco de Palythoa caribaeorum (Cnidaria, Anthozoa) da praia de Porto de Galinhas-PE, Brasil". Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/27694.
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FACEPE
Palythoa caribaeorum (baba-de-boi) é um cnidário marinho que secreta um muco viscoso o qual apresenta propriedades farmacológicas e abriga uma série de bactérias com potencial de aplicação biotecnológica. No presente trabalho, objetivou-se obtenção desses micro-organismos associados ao muco de populações do zoantídeo oriundas da praia de Porto de Galinhas, litoral sul de Pernambuco, para fins de prospecção de produtos naturais. Foram isoladas 281 bactérias das quais 55 cepas se mantiveram viáveis após o subcultivo e preservação. A identificação dos isolados foi realizada a partir do sequenciamento dos genes 16S rDNA e rpoB, resultando na obtenção de 18 espécies pertencentes aos filos Firmicutes (37 isolados, 67%), Actinobacteria (11 isolados, 20%), Proteobacteria (5 isolados, 9%) e Bacteroidetes (2 isolados, 4%). Exiguobacterium aurantiacum correspondeu à espécie mais abundante com 9 isolados, enquanto o gênero Bacillus se apresentou como o mais diverso, totalizando 19 isolados distribuídos em 8 espécies distintas. Os isolados de Bacillus spp. foram selecionados para investigação do potencial de produção de 8 enzimas em meio sólido. Todas as cepas produziram pelo menos 4 das enzimas investigadas, com gelatinase sendo a mais frequente (19 isolados), seguida por esterase (18), caseinase (17), amilase (12), poligalacturonase (12), pectato liase (12), celulase (11) e lipase (11). Os isolados B. thuringiensis BCLTHR-01 e B. subtilis BCLSUB-02, 03 e 04 foram os melhores produtores enzimáticos, com resultados positivos em todos os ensaios. A cepa BCLTHR-01 também foi investigada quanto ao potencial biolarvicida contra Aedes aegypti. Para produção das toxinas, foi desenvolvido um processo fermentativo em biorreator operando em batelada com um meio de cultura desprovido de carboidratos como fonte de carbono. A biomassa tóxica concentrada (10⁹ UFC/mL) obtida após 48h de fermentação mostrou atividade biológica com valores de CL₅₀ de 0,849 ppm (intervalo de 0,792 a 0,900 ppm) e de CL₉₀ de 1,285 ppm (intervalo de 1,190 a 1,434 ppm), comprovando o potencial de aplicação deste isolado para o controle do vetor. As bactérias marinhas associadas a P. caribaeorum são potencialmente excelentes fontes de metabólitos bioativos. A presença de espécies capazes de degradar hidrocarbonetos, fixar nitrogênio, metabolizar enxofre e produzir enzimas e toxinas com diversas propriedades sugere que o zoantídeo se beneficia através da assimilação de compostos complementares ao seu metabolismo e através da aquisição de um mecanismo adicional de defesa contra patógenos. A complexidade do ambiente marinho induz à adaptação dos micro-organismos, resultando na produção de uma diversidade de moléculas com propriedades únicas que lhes permitem suportar as condições severas dos processos industriais, tornando-as interessantes objetos para aplicação industrial e biotecnológica.
Palythoa caribaeorum (baba-de-boi) is a marine cnidarian that secretes a viscous mucus which presents pharmacological properties and harbors several bacteria with potential for biotechnological application. In the present work, we aimed to obtain these microorganisms associated with the mucus of zoanthid populations from the beach of Porto de Galinhas, south coast of Pernambuco, to prospect for natural products. 281 bacteria were isolated, of which 55 strains remained viable after subculture and preservation. The identification of the isolates was done by sequencing the 16S rDNA and rpoB genes, resulting in 18 species belonging to the Firmicutes (37 isolates, 67%), Actinobacteria (11 isolates, 20%), Proteobacteria (5 isolates, 9 %) and Bacteroidetes (2 isolates, 4%). Exiguobacterium aurantiacum corresponded to the most abundant species with 9 isolates, while the genus Bacillus was the most diverse, totaling 19 isolates distributed in 8 different species. The isolates of Bacillus spp. were selected to investigate the potential to produce 8 enzymes in solid medium. All strains produced at least 4 of the investigated enzymes, with gelatinase being the most frequent (19 isolates), followed by esterase (18), caseinase (17), amylase (12), polygalacturonase (12), pectate lyase (12), cellulase (11) and lipase (11). The isolates B. thuringiensis BCLTHR-01 and B. subtilis BCLSUB-02, 03 and 04 were the best enzymatic producers, displaying positive results in all the assays. The strain BCLTHR-01 was also investigated for its biolarvicidal potential against Aedes aegypti. To produce the toxins, a fermentation process was developed in bioreactor batching with a culture medium devoid of carbohydrates as carbon source. The concentrated toxic biomass (10⁹ CFU/mL) obtained after 48h of fermentation showed biological activity with LC₅₀ value of 0.849 ppm (range of 0.792 to 0.900 ppm) and CL₉₀ value of 1.285 ppm (range of 1.190 to 1.434 ppm), proving the application potential of this isolate for vector control. Marine bacteria associated with P. caribaeorum are potentially excellent sources of bioactive metabolites. The presence of species capable of degrading hydrocarbons, fixing nitrogen, metabolizing sulfur and producing enzymes and toxins with different properties suggests that the zoanthide benefits through the assimilation of compounds complementary to its metabolism and through the acquisition of an additional mechanism of defense against pathogens. The complexity of the marine environment induces the adaptation of microorganisms, resulting in the production of a diversity of molecules with unique properties that allow them to withstand the harsh conditions of industrial processes, making them interesting objects for industrial and biotechnological application.
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GUIDESI, ELENA. "Approccio integrato alla selezione di nuovi probiotici per l'applicazione nell'uomo". Doctoral thesis, Università Cattolica del Sacro Cuore, 2016. http://hdl.handle.net/10280/10796.
Testo completoAbstract (sommario):
Durante la mia tesi di dottorato ho selezionato nuovi potenziali ceppi probiotici, combinando l'approccio convenzionale con l’utilizzo di piattaforme di nuova concezione. Mi sono concentrata inizialmente sul cosiddetto "screening tradizionale" finalizzato all'isolamento di nuovi ceppi batterici di lattobacilli e bifidobatteri e alla valutazione della loro sicurezza per il consumo umano e della loro efficacia. I ceppi selezionati sono stati quindi sottoposti ad uno screening più specifico, a seconda dell'applicazione a cui sarebbero stati destinati. In questa fase sono stati utilizzati sia test in vitro che modelli animali, al fine di valutare l'applicabilità dei ceppi di recente selezionati come probiotici per la promozione della salute umana e il loro possibile impiego in campo alimentare. Ho valutato il potenziale utilizzo dei ceppi nell’integrazione alimentare di soggetti che seguono diete ad alto contenuto proteico per ridurre il rischio di accumulo intestinale di ammine biogene, e ho individuato un ceppo di Lactobacillus con presunta attività ammino-degradativa. L'obiettivo principale di un’altra attività di screening è stato lo studio degli effetti immunomodulanti di nuovi ceppi: combinazioni di probiotici sono risultati buoni candidati per il trattamento delle malattie infiammatorie e autoimmuni (miastenia grave e sclerosi multipla) nel modello di topo. Infine, i ceppi sono stati sottoposti a screening per una potenziale applicazione in campo alimentare, finalizzata ad indagare la possibilità di produrre formulazioni di probiotici “atomizzati” da utilizzare insieme alla base commerciale del gelato.During my PhD thesis I screened new potential probiotic strains by combining conventional approach to newly designed platforms. I focused first on the so-called "conventional screening” aimed to the isolation of new bacterial strains of lactobacilli and bifidobacteria and to assess their safety for human consumption and their efficacy by in-vitro methods. Selected strains were then submitted to a targeted screening by specifically designed models, depending on the application to which they would be destined. These models combined in vitro tests and animal models in order to assess the applicability of newly selected strains as probiotics for the promotion of human health and their possible use in food field. I evaluated the potential use of strains in the food supplementation of subjects that follow high-protein diets to reduce the risk of intestinal accumulation of biogenic amines, and I identified a strain of Lactobacillus with alleged amino degradative activity. The main objective of another screening activity was the study of the immunoregulatory effects of new strains: combinations of probiotics resulted good promising candidates for the treatment of inflammatory and autoimmune diseases (myasthenia gravis and multiple sclerosis) in rat model. Finally, strains were screened for a potential application in food field, in order to investigate the possibility of producing spray-dried probiotic formulations to be used together with commercial ice-cream bases.
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GUIDESI, ELENA. "Approccio integrato alla selezione di nuovi probiotici per l'applicazione nell'uomo". Doctoral thesis, Università Cattolica del Sacro Cuore, 2016. http://hdl.handle.net/10280/10796.
Testo completoAbstract (sommario):
Durante la mia tesi di dottorato ho selezionato nuovi potenziali ceppi probiotici, combinando l'approccio convenzionale con l’utilizzo di piattaforme di nuova concezione. Mi sono concentrata inizialmente sul cosiddetto "screening tradizionale" finalizzato all'isolamento di nuovi ceppi batterici di lattobacilli e bifidobatteri e alla valutazione della loro sicurezza per il consumo umano e della loro efficacia. I ceppi selezionati sono stati quindi sottoposti ad uno screening più specifico, a seconda dell'applicazione a cui sarebbero stati destinati. In questa fase sono stati utilizzati sia test in vitro che modelli animali, al fine di valutare l'applicabilità dei ceppi di recente selezionati come probiotici per la promozione della salute umana e il loro possibile impiego in campo alimentare. Ho valutato il potenziale utilizzo dei ceppi nell’integrazione alimentare di soggetti che seguono diete ad alto contenuto proteico per ridurre il rischio di accumulo intestinale di ammine biogene, e ho individuato un ceppo di Lactobacillus con presunta attività ammino-degradativa. L'obiettivo principale di un’altra attività di screening è stato lo studio degli effetti immunomodulanti di nuovi ceppi: combinazioni di probiotici sono risultati buoni candidati per il trattamento delle malattie infiammatorie e autoimmuni (miastenia grave e sclerosi multipla) nel modello di topo. Infine, i ceppi sono stati sottoposti a screening per una potenziale applicazione in campo alimentare, finalizzata ad indagare la possibilità di produrre formulazioni di probiotici “atomizzati” da utilizzare insieme alla base commerciale del gelato.During my PhD thesis I screened new potential probiotic strains by combining conventional approach to newly designed platforms. I focused first on the so-called "conventional screening” aimed to the isolation of new bacterial strains of lactobacilli and bifidobacteria and to assess their safety for human consumption and their efficacy by in-vitro methods. Selected strains were then submitted to a targeted screening by specifically designed models, depending on the application to which they would be destined. These models combined in vitro tests and animal models in order to assess the applicability of newly selected strains as probiotics for the promotion of human health and their possible use in food field. I evaluated the potential use of strains in the food supplementation of subjects that follow high-protein diets to reduce the risk of intestinal accumulation of biogenic amines, and I identified a strain of Lactobacillus with alleged amino degradative activity. The main objective of another screening activity was the study of the immunoregulatory effects of new strains: combinations of probiotics resulted good promising candidates for the treatment of inflammatory and autoimmune diseases (myasthenia gravis and multiple sclerosis) in rat model. Finally, strains were screened for a potential application in food field, in order to investigate the possibility of producing spray-dried probiotic formulations to be used together with commercial ice-cream bases.
Libri sul tema "Microbiological screening"
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Wilson, A. P. R. Microbiological surveillance in the critically ill. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199600830.003.0281.
Testo completoAbstract (sommario):
Patients in the ICU are at high risk of acquiring multiresistant pathogens. Surveillance quickly identifies outbreaks and promotes antimicrobial stewardship. Catheter-related bacteraemia is often used as a performance measure and intervention using a package of preventative measures can be very successful. Ventilator-associated pneumonia in contrast can be difficult to define accurately. Water sources should be monitored. Pseudomonas aeruginosa may become established in taps and cause invasive infections especially in neonates. Screening of nasal swabs for MRSA followed by topical suppression has been effective in reducing spread during ICU admission. With rising prevalence of multiresistant Gram-negative species, screening of faeces or rectal swabs may become necessary. Acinetobacter is very disruptive if it causes an outbreak and it can be difficult to control. Screening is one method of limiting its’ spread. National surveillance networks are increasing and may be mandatory as they appear to be successful in controlling nosocomial infection.
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Microbiological screening of the indoor air quality in the Polk County Administration building: Project summary. Cincinnati, OH: U.S. Environmental Protection Agency, National Risk Management Research Laboratory, 1995.
Cerca il testo completo
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Provan, Drew, Trevor Baglin, Inderjeet Dokal, Johannes de Vos e Hassan Al-Sader. Haematopoietic stem cell transplantation. Oxford University Press, 2015. http://dx.doi.org/10.1093/med/9780199683307.003.0009.
Testo completoAbstract (sommario):
Haemopoietic stem cell transplantation (SCT) - Indications for haemopoietic SCT - Allogeneic SCT - Autologous STC - Investigations for BMT/PBSCT - Pretransplant investigation of donors - Bone marrow harvesting - Peripheral blood stem cell mobilization and harvesting - Microbiological screening for stem cell cryopreservation - Stem cell transplant conditioning regimens - Infusion of cryopreserved stem cells - Infusion of fresh non-cryopreserved stem cells - Blood product support for SCT - Graft-versus-host disease (GvHD) prophylaxis - Acute GvHD - Chronic GvHD - Veno-occlusive disease (syn. sinusoidal obstruction syndrome) - Invasive fungal infections and antifungal therapy - CMV prophylaxis and treatment - Post-transplant vaccination programme and foreign travel - Longer term effect post-transplant - Treatment of relapse post-allogeneic SCT - Discharge and follow-up
Capitoli di libri sul tema "Microbiological screening"
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Wagner-Döbler, I., R. Erb, P. Rapp, I. Brümmer, B. Hauser, R. Gleitsman e R. H. Müller. "On Site Assessment of Microbiological Diversity and Activity". In Field Screening Europe, 221–24. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-009-1473-5_51.
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Trautmann, M., e P. M. Lepper. "Microbiological Findings and Antiinfective Treatment Strategies". In Immunological Screening and Immunotherapy in Critically ill Patients with Abdominal Infections, 29–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/978-3-642-59455-7_3.
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Leoni, Livia, e Paolo Landini. "Microbiological Methods for Target-Oriented Screening of Biofilm Inhibitors". In Methods in Molecular Biology, 175–86. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4939-0467-9_12.
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Falasconi, M., E. Comini, I. Concina, V. Sberveglieri e E. Gobbi. "Electronic Nose and Its Application to Microbiological Food Spoilage Screening". In Sensing Technology: Current Status and Future Trends II, 119–40. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-02315-1_6.
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Gilbert, Peter, e Michael R. W. Brown. "Screening for Novel Antimicrobial Activity/Compounds in the Pharmaceutical Industry". In Microbiological Quality Assurance, 247–60. CRC Press, 2018. http://dx.doi.org/10.1201/9781351074551-16.
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Lappin-Scott, Hilary M., Jana Jass e J. William Costerton. "Screening for Novel Compounds/Activity in the Environmental Protection Industries". In Microbiological Quality Assurance, 261–74. CRC Press, 2018. http://dx.doi.org/10.1201/9781351074551-17.
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MARTINEZ, OCTAVIO V. "MICROBIOLOGICAL SCREENING OF CADAVER DONORS AND TISSUES FOR TRANSPLANTATION". In Advances in Tissue Banking, 143–55. WORLD SCIENTIFIC, 2004. http://dx.doi.org/10.1142/9789812796646_0005.
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Arunachalam, Kannappan, e Chunlei Shi. "Developments in rapid detection/high throughput screening techniques for identifying pathogens in food". In Advances in ensuring the microbiological safety of fresh produce, 97–136. Burleigh Dodds Science Publishing, 2023. http://dx.doi.org/10.19103/as.2023.0121.08.
Testo completoAbstract (sommario):
For reasons of food safety and quality assurance, rapid identification of pathogens causing spoilage and infections in food matrices is essential. Conventional approaches include enrichment of microbial pathogens in a range of non-selective and pathogen-specific selective media, followed by biochemical and phenotypic identification. In conventional culturing techniques, time-dependent detection is a major obstacle when it comes to delicate foods such as fish, dairy products and fresh produce. To overcome the limits of conventional approaches, numerous detection technologies such as molecular-, spectroscopy- and spectrometry-based methods, as well as optical phenotyping and biosensor methods are now available. This chapter provides an overview of the principles, mechanisms and applications of new and emerging technologies for microbial identification in food systems. It also provides researchers in the field of food safety and quality assurance with the known advantages and limitations of available rapid detection techniques for identifying pathogens in foods.
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Dean, Gillian, e Jonathan Ross. "Pelvic inflammatory disease". In Oxford Textbook of Obstetrics and Gynaecology, a cura di Sabaratnam Arulkumaran, William Ledger, Lynette Denny e Stergios Doumouchtsis, 536–49. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198766360.003.0043.
Testo completoAbstract (sommario):
Pelvic inflammatory disease is a sexually transmitted infection of the female upper genital tract. Rates of pelvic inflammatory disease have fallen in many countries over the last 10 years, at least in part due to increased screening for chlamydial infection. The clinical spectrum ranges from asymptomatic infection through to severe disease requiring hospitalization. Due to the non-specific nature of the condition, diagnosis can be challenging. All sexually active women presenting with acute lower abdominal pain should have a pregnancy test to rule out ectopic pregnancy. Treatment must be initiated as soon as the diagnosis is suspected and include antibiotics covering a broad spectrum of pathogens. Delay in diagnosis increases the risk of adverse sequelae including ectopic pregnancy and infertility. It is recommended that current and recent sexual partners receive empirical treatment, regardless of symptoms or microbiological results, and refrain from sexual contact until completion of therapy. Through better public understanding of the symptoms of pelvic inflammatory disease, women seeking earlier medical attention may reduce the risk of reproductive damage.
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Diniz, Roseane Costa, Luís Cláudio Nascimento da Silva, Marilene Mendes Costa, Fábio Augusto Siqueira dos Santos e Luan Victor Pereira de Sousa. "Selection of Staphylococcus aureus DNA replication inhibitors". In Themes focused on interdisciplinarity and sustainable development worldwide V. 02. Seven Editora, 2024. http://dx.doi.org/10.56238/sevened2024.003-050.
Testo completoAbstract (sommario):
Introduction: S. aureus is an important pathogen that causes nosocomial infections, food poisoning by release of enterotoxins and toxic shock syndrome through the injection of super antigens into the bloodstream. The β-clamp protein of S. aureus is a process-promoting factor for most enzymes in prokaryotic DNA replication and its dimerization is essential for the deleterious action of the pathogen. Objective: In this work, we report the application of the double hybrid system to select β-clamp dimerization inhibitors of S. aureus from Caatinga plant extracts, especially Buchenavia tetraphylla. Material and Methods: (1) preparation of organic extracts of Buchenavia tetraphylla was prepared as previously reported (2) The β-clamp-β-clamp interaction was evaluated using a hybrid double bacterial system (BTH), based on the reconstitution of the activity of the enzyme adenylate cyclase (cya) from Bordetella pertussis and cloned in Escherichia coli. (3) The antimicrobial activity of active extracts was evaluated by determining the minimum inhibitory concentration (MIC) against S. aureus 8325-4 (4) To identify compounds potentially responsible for the activity, the active extracts were subjected to a non-segmented analysis by LC-MS/Q-TOF (5) The in silico studies were carried out by searching for the ligand structures, construction and validation of the 3D model of the β-clamp and molecular docking between ligands and protein target of S. aureus and the human CYP3A4 hepatic system. Results and Discussion: There was a high interaction (in the order of 4,800 kcal/mol) between buchenavianine and analogues with β-clamp with no significant difference between them. On the other hand, the interaction between buchenavianine and human CYP3A4 analogues was (of the order of 2,200 kcal/mol) following the same principles of electronegativity of the elements. The purpose of this analysis is to understand how the β-clamp protein interacts with the main human liver metabolization protein. The interaction between buchenavianine and human CYP3A4 analogues was 2 times lower than buchenavianine and S. aureus β-clamp analogues, and this shows that between the two targets studied here (S. aureus β-clamp and human CYP3A4) the ligands will be preferentially attracted to the S. aureus β-clamp, which ratifies them as viable inhibitors of the S. aureus DNA replication process. Conclusion: The combination of microbiological, chemical and computational resources allowed to indicate molecules present in the plant extract capable of interacting with the β-clamp of S. aureus. The approach presented here promotes a rational biochemical screening for ligand selection with better possibilities for subsequent bench tests, saving financial resources and optimizing results in drug research and development.
Atti di convegni sul tema "Microbiological screening"
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Sousa, Matheus Henrique Oliveira de, Gilvan de Oliveira Costa Dias e Joselene Ribeiro de Jesus Santos. "Phytochemical prospecting, identification and evaluation of the microbiological activity of secondary metabolites of Annona mucosa Jacq". In V Seven International Multidisciplinary Congress. Seven Congress, 2024. http://dx.doi.org/10.56238/sevenvmulti2024-049.
Testo completoAbstract (sommario):
The present work describes the results obtained for the phytochemical and microbiological studies of the 70% hydroethanolic extract, its fractions and metabolites isolated from the leaves of Biribazeiro ( Annona mucosa Jacq.). Initially, the hydroethanolic extract (70%) of the vegetable leaves was prepared and a phytochemical screening was carried out in search of the secondary metabolites of study. The tests confirmed the presence of tannins, flavonols, flavanones, flavanonols, xanthones, leucoanthocyanidins, anthocyanidins, free steroids,
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Pollmann, Kathrin, Natascha Köstlin-Gille, Bernhard Beedgen e Christian Gille. "Reduction in sepsis rate in very low birth weight infants after introduction of microbiological screening measures". In Abstracts zur 49. Jahrestagung der Gesellschaft fär Neonatologie und Pädiatrische Intensivmedizin (GNPI). Georg Thieme Verlag KG, 2023. http://dx.doi.org/10.1055/s-0043-1769235.
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Mota, Ana Cristina, Matheus Henrique Oliveira de Sousa, Gilvan de Oliveira Costa Dias e Joselene Ribeiro de Jesus Santos. "Phytochemical study and biological activity of the bark of the plant species araticum bravo (Annona tomentosa RE Fr.)". In V Seven International Multidisciplinary Congress. Seven Congress, 2024. http://dx.doi.org/10.56238/sevenvmulti2024-050.
Testo completoAbstract (sommario):
Annona tomentosa RE Fr. (Annonaceae), known in Brazil as Araticum-bravo or Araticum de moita, is a small tree found throughout Brazilian territory, mainly in coastal areas, its distribution is discontinuous, appearing in open fields, in savanna of shrub trees and in the cerradão, where the vegetation is denser. All parts of this vegetable are used in folk medicine, it has been used mainly to combat diarrhea, stomatitis, headache, neuralgia, boils, ulcers and to eradicate lice as well as anti-rheumatic. Based on data obtained by bibliographical survey, this work sought information of a chemical nature, through phytochemical and microbiological screening through antimicrobial activity tests. In the phytochemical screening, the presence of substances belonging to the classes of phenols, tannins, anthocyanins, anthocyanidins, flavonoids, xanthones saponins, triterpene steroids and alkaloids were confirmed. Confirmation for alkaloids was performed by chromatoplates. Standard strains (ATCC) of Gram-positive bacteria Staphylococcus aureus 25923, Gram-negative bacteria Pseudomonas aeruginosa 27853, Escherichia coli 35218, Klebsiella pneumoniae 700603 were used for the evaluation of antimicrobial activity. Clinical isolates of Acinectobacter were used in the microbiological tests. baumannii and the fungus Candida albicans . The antimicrobial potential of the extract was analyzed using the drilling technique in Müller Hinton medium, the results demonstrated that the A. tomentosa peels have a growth inhibitory potential on the Gram-positive bacterium, S. aureus , and on clinical microorganisms with emphasis on for A. baumanni with halo formation (20 mm) respectively.
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Ferdes, Mariana, e Rodica Roxana Constantinescu. "Isolation and characterization of fungal and bacterial proteolytic strains from chrome shavings". In The 8th International Conference on Advanced Materials and Systems. INCDTP - Leather and Footwear Research Institute (ICPI), Bucharest, Romania, 2020. http://dx.doi.org/10.24264/icams-2020.ii.9.
Testo completoAbstract (sommario):
The chrome shavings waste obtained as a result of the leather finishing process accumulates in a large volume in tanneries and represent a major problem for the environment. This waste are particularly resistant to attack of microorganisms, due to the significant concentration of chromium and are thus difficult to degrade. In this study, chrome shavings were analyzed microbiologically by determining the total number of germs and the number of yeasts and molds on specific culture media. Several bacterial and fungal strains were isolated from the cultures in Petri dishes, after the growth of the colonies. These strains were characterized in terms of the production of proteolytic enzymes, by a method of screening on the media with casein, which allows the determination of proteolytic indices of microorganisms. As a result of the tests performed, five bacterial strains probably belonging to the genus Bacillus and two fungal strains from the genera Penicillium and Cladosporium were selected.