Dissertations / Theses on the topic 'MALDI-TOF MS'
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Leander, Ellinor. "Artidentifiering av mögelsvamp med MALDI-TOF MS." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-80166.
Full textRapid and accurate species identification is crucial for successful treatment of fungal infections, especially among immunosuppressed patients. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is used routinely at clinical laboratories to identify characteristic protein patterns of bacteria and yeast by the interpretation of protein spectra in a database for accurate species identification. The hard cell wall of the mold and the heterogeneous growth with varying protein expression due to maturation, complicates identification with MALDI-TOF MS. The potential benefits of this method compared to microscopy as traditional method are shortened turn-around times, safer species identification of more species that is independent on subjective morphological assessment. The purpose of the study was to investigate whether MALDI-TOF MS could be adapted and used for the identification of molds in clinical routine diagnostics. Four reference strains (Aspergillus niger, A.fumigatus, A.terreus, A.flavus) and a clinical isolate (A.terreus) were examined. The preparation methods (I) complete formic acid extraction, (II) direct application and (III) suspension in distilled water were used for analysis of spores and frontmycelium from younger and older mold cultures. Two different masspektradatabases for species identification were compared; routine database BDAL and the specialized mold database, Filamentous Fungi Library. Also the collecting technique of mold prior to analysis with MALDI-TOF MS was evaluated. Sometimes, the species identification improved after extraction of mold cultures, while in other cases direct application was sufficient. Cultures with a lot of spores tended to give slightly more species identifications in BDAL regardless of the age of cultures. Filamentous Fungi Library, in some cases, tended to improve the performance compared to BDAL for younger cultures. More studies are required to evaluate and optimize MALDI-TOF MS as a method of mold identification.
Kempka, Martin. "Improved mass accuracy in MALDI-TOF-MS analysis." Licentiate thesis, Stockholm : Division of Analytical Chemistry, Royal Institute of Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-313.
Full textHalgunset, Anders. "Typing av Legionella pneumophila med MALDI-TOF MS." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bioteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-24697.
Full textBertilsson, Sarah. "Glycanmapping of glycoproteins with UPLC-FLR-MALDI/TOF-MS." Thesis, Uppsala universitet, Analytisk kemi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-228040.
Full textDempwolf, Wibke. "MALDI-TOF in der kontrollierten radikalischen Polymerisation und Präpolymeranalyse." Clausthal-Zellerfeld Papierflieger, 2007. http://d-nb.info/990376834/04.
Full textWorster, Belinda Mary. "MALDI-TOF-MS and neuropeptide signalling in the nervous system." Thesis, University of Sussex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360682.
Full textNiare, Sirama. "Identification du repas sanguin des moustiques par MALDI-TOF MS." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0575/document.
Full textMALDI-TOF MS (Matrix Assisted, Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry) is a proteomic technique that routinely used for microorganisms identification in clinical microbiology laboratory. Recently, the MALDI-TOF MS was successfully used as a innovative tool for arthropod identification. Thus, in this work we evaluated the MALDI-TOF MS to identify the blood meal sources from engorged mosquitoes. In the first part of our work, a bibliographical review was carried out on the different methods (serological, molecular biology) known in the trophic preference determination of hematophagous arthropods. The second part was optimization of the MALDI-TOF MS for identifying the origin of the blood meal of mosquitoes. For optimization, the Anopheles gambiae Giles and Aedes albopictus were artificially fed on several vertebrate hosts blood using the Hemotek device for two hours under standard conditions. Our results showed intra-species reproducibility and inter-species specificity of MS spectra from mosquitoes engorged on the same or different vertebrate hosts. The MS spectra querying against the database reveal a correct identification of the the blood meal origin from the specimens collected less than 24 hours post-feeding. For field samples, MALDI-TOF MS allowed to detect the mosquitoes blood meal fed on wide variety of domestic hosts. Consequently the MALDI-TOF MS technique would be an effective tool for epidemiological surveys of vector-borne diseases and the identification of the trophic preference of mosquito freshly engorged
Dallacker-Losensky, Kevin. "Identifizierung von obligaten Anaerobiern der Bacteroides fragilis Gruppe einschließlich Metronidazol-resistenter und Enterotoxin-positiver Stämme mittels MALDI-TOF MS." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-206555.
Full textChen, Shuo. "MALDI-TOF MS data processing using wavelets, splines and clustering techniques." [Johnson City, Tenn. : East Tennessee State University], 2004. http://etd-submit.etsu.edu/etd/theses/available/etd-1112104-113123/unrestricted/ChenS121404f.pdf.
Full textTitle from electronic submission form. ETSU ETD database URN: etd-1112104-113123 Includes bibliographical references. Also available via Internet at the UMI web site.
Hamdi, Cassandra. "Clostridium difficile : Rapid typing Clostridium difficile using MALDI-TOF MS analysis." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-17659.
Full textElvingson, Ebba. "Art- och genusbestämning av bakterier direkt från blododlingar med MALDI-TOF MS." Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-36355.
Full textLiti, Samone. "Evaluation of sample preparation techniques for MALDI-TOF-MS analysis of oligosaccharides." Thesis, Uppsala universitet, Avdelningen för analytisk farmaceutisk kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-277957.
Full textYe, LiYun. "Characterization of A-type Proanthocyanidins in Peanut Skins Using MALDI-TOF MS." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/72283.
Full textPh. D.
Nakano, Satoshi. "Development and evaluation of MALDI-TOF MS-based serotyping for Streptococcus pneumoniae." Kyoto University, 2016. http://hdl.handle.net/2433/215402.
Full textNorrman, Cassandra. "Validering av online databas för identifiering av svamp med MALDI-TOF MS." Thesis, Umeå universitet, Biomedicinsk laboratorievetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160083.
Full textLobão, Francisco José Barros. "Valor do MALDI-TOF no diagnóstico bacteriológico na fibrose quística." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13870.
Full textA fibrose quística é a doença hereditária autossómica recessiva frequentemente associada à raça caucasiana. Atualmente, a principal causa de morbilidade e mortalidade é o declínio gradual da função pulmonar devido à colonização crónica por diversas bactérias e fungos, onde os bacilos Gram negativo não fermentadores têm um papel fundamental. O objetivo deste trabalho é comparar duas tecnologias diferentes de identificação bacteriana, na sua capacidade de fornecer uma identificação o mais completa e fidedigna possível, dos bacilos de Gram negativo não fermentadores, em doentes com fibrose quística. Dentro deste objetivo, pretendia-se avaliar o impacto e possível introdução da tecnologia MALDI-TOF MS na rotina de um grande hospital. Para isso, foi realizada uma recolha de dados dos resultados bacteriológicos das amostras respiratórias de 85 doentes com fibrose quística do Centro Hospitalar de São João, EPE. De janeiro de 2002 a 28 de fevereiro de 2013 foram analisados os microrganismos isolados em 1000 amostras, utilizando o VITEK® 2, onde 77,5% dos isolamentos foram identificados ao nível da espécie, 12% ao nível do complexo e 6,7% ao nível do género, não tendo identificado a bactéria em 3,8%. Entre 01 de março de 2013 e 08 de agosto de 2014 foram analisadas 175 amostras usando o VITEK® MS, obtendo uma identificação ao nível da espécie em 73,1% das vezes, 6,3% ao nível do complexo e 20,6% ao nível do género. Assim, é possível concluir que a introdução da tecnologia MALDI-TOF MS permitiu um melhoramento na identificação bacteriana, com a vantagem de fornecer uma identificação fidedigna em apenas alguns minutos e utilizando uma pequena quantidade de inóculo. No entanto, constatou-se que há necessidade de melhorar a base de dados para alguns géneros de bacilos Gram negativo não fermentadores, de forma a possibilitar uma identificação ainda mais eficaz.
Cystic fibrosis is the most frequent autossomic recessive hereditary disease in Caucasian race. Gradual decline of pulmonary function originated by chronic bacteria and fungi colonization is the leading cause of morbidity and mortality in cystic fibrosis and non-fermenters bacilli have a fundamental role in the colonization. The objective of this work is compare two different bacteria identification technologies through the ability to provide the most complete and reliable identification possible of non-fermenters Gram negative bacilli in cystic fibrosis patients. Within this aim, the intention was evaluate the impact and possible introduction of MALDI-TOF MS technology in the routine of a large hospital. To achieve that goal, a data collection of bacteriological results from respiratory samples of 85 cystic fibrosis patients from Centro Hospitalar de São João, EPE was performed. Between January 02 2002 and February 28 2013, microorganisms isolated in 1000 samples were analysed using VITEK® 2, which identified at species level in 77.5%, 12% at complex level and 6.7% at genus level, and in 3.8% of cases no identification was made. Between March 01 2013 and August 08 2014 have been analysed 175 samples using VITEK® MS and it proceed the identification at species level in 73.1%, 6.3% at complex level and 20.6% at genus level. Thus, it is possible to conclude that MALDI-TOF MS technology has enabled an improvement in bacterial identification, taking the advantage of providing an identification in just a few minutes. However, it is necessary to improve the database for some genera of non-fermenters Gram negative bacilli, in order to permit a more efficient identification.
Sorensen, Christina M. "ESI-MS and MALDI-TOF-MS for the characterization and analysis of metallo-oligomers and proteins." Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=1031044031&sid=4&Fmt=2&clientId=18949&RQT=309&VName=PQD.
Full textMatajira, Carlos Emilio Cabrera. "Identificação de estirpes do gênero Streptococcus pela técnica de reação em cadeia da polimerase (PCR) e espectrometria de massa MALDI-TOF." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-27102015-082622/.
Full textTraditional microbiological methods such as isolation, Gram staining and biochemical tests help to identify the Streptococcus genus, however, the species present broad phenotypic variation, making it difficult for their identification or even differentiation just by these methods. One of the most important species in swine, Streptococcus suis, has led to great losses worldwide and has been described as an important zoonosis in some countries. S. suis is present in the upper airways, especially colonizing tonsils, oral and nasal cavities facilitating the high dissemination by direct contact, especially among piglets between 4 to 12 weeks of age. The most common clinical manifestations in pigs infected by S. suis are meningitis, arthritis and pneumonia. The aim of this study was to identify Streptococcus strains by polymerase chain reaction (PCR), 16S rRNA gene partial sequencing and MALDI-TOF mass spectrometry (MALDI-TOF MS). PCR and MALDI-TOF MS analysis resulted in the identification of 215 strains as S. suis and 35 as different species of the Streptococcus genus. The identification of the 35 strains belonging to other species of the genus by MALDI-TOF MS was confirmed by 16S rRNA gene partial sequencing, and both techniques presented 100% concordance. These results demonstrate the high efficiency in the use of the evaluated techniques for the identification of S. suis and the other species of the Streptococcus genus. The MALDI-TOF MS technique, despite the equipment high cost, presented the advantage of being fast, have low cost per analysis and reduced material usage
Mello, Rodrigo Ventura de. "Aplicação de MALDI-TOF MS na caracterização de microalgas da família Selenastraceae (Chlorophyta)." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8748.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
The morphological variability in the Selenastraceae family has been a barrier to a good establishment of well-defined taxonomic groups. Several studies with molecular compounds have already demonstrated its importance in the elucidation of this relation. In this scenario, the present study used a matrix-assisted laser desorption ionization timeof- flight mass-spectrometry (MALDI-TOF MS) technique as a tool to differentiation of the microalgae of this family at the species and strains levels. A group of 18 strains, belong to in 12 different species, of freshwater microalgae was selected. Cells and dissolved organic matter (DOM) were analyzed in the middle exponential growth phase. The analyzes were performed in two different mass ranges: 400 to 2,000 Da and 2,000 to 20,000 Da. Each strain that yielded unique spectra with a good resolution of peaks and reproducibility was selected for clusters analyzes. These spectra were used to make a dissimilarity analysis that showed the capability of differentiation of the strains and species. The strains of the genera Monoraphidium were not all grouped, possibly because it is a polyphyletic group. The praticity and quickness of this technique for data acquisition, allied with the low cost of the analysis, are factors that favor its application in taxonomic studies.
A baixa variedade morfológica presente na família Selenastraceae tem sido uma barreira para o estabelecimento de grupos taxonômicos bem definidos. Estudos realizados com diversos marcadores moleculares já demonstraram a importância dos compostos produzidos por esses organismos na elucidação dessas relações. Nesse cenário, o presente estudo buscou avaliar a aplicação da espectrometria de massa por MALDI-TOF como ferramenta para a discriminação de cepas e espécies dessa família. Foram selecionadas 18 cepas, classificadas em 12 espécies diferentes, de microalgas de água doce. As células e a matéria orgânica dissolvida (MOD) analisadas foram amostradas de cultivos no meio da fase exponencial de crescimento. As análises foram feitas em duas extensões de massa: massas baixas (400 – 2000 Da) e massas altas (2 – 20 kDa). Para cada tipo de análise foram selecionadas as cepas que renderam espectros com boa resolução de picos. Esses espectros foram então utilizados em análises de dissimilaridade para a elaboração de dendrogramas, evidenciando a capacidade da técnica para a distinção de cepas e espécies. Apesar das cepas do gênero Monoraphidium não ficarem todas agrupadas, o que possivelmente ocorre devido ao fato do grupo ser polifilético. A grande rapidez e praticidade desta técnica para a obtenção de dados, aliado ao baixo custo das análises, são fatores que favorecem a sua aplicação neste tipo de estudo.
Sauerbrey, Kerstin. "Möglichkeiten und Grenzen der Mastitisdiagnostik mittels MALDI-TOF MS-Analytik und molekularbiologischen Methoden." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-179910.
Full textOlsson, Linnea. "Detection of synergistic activity of antibiotics in Klebsiella pneumoniae using MALDI-TOF MS." Thesis, Örebro universitet, Institutionen för hälsovetenskap och medicin, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-45032.
Full textBorgmann, Toralf Harald. "Schnelle Identifizierung von oralen Actinomyces-Arten des subgingivalen Biofilms mittels MALDI-TOF-MS." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-189236.
Full textYssouf, Amina. "Identification des arthropodes vecteurs et des micro-organismes associés par MALDI-TOF-MS." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM5031/document.
Full textArthropods are vectors bloodsucking and can ensure the active biological transmission of a pathogen responsible of human or veterinary diseases. The vector control and vectors epidemiological surveillance are essential in the strategy against the vectors-borne diseases. Accurate, reliable and rapid identification of vectors and associated pathogens are essential. Thus, in this project we evaluated the use of MALDI-TOF MS for the arthropods vectors identification as well as for the detection of associated pathogens. This proteomics technology emerged since few years ago and is currently used in routine for bacteria identification in many microbiology laboratories. In the first part of our work, we used the MALDI TOF to identify the tick, mosquito and flea species. For each arthropod, we determined which part allowed obtaining reproducible spectra by MALDI TOF and correct identification by blind test, after reference database creation. The second part consisted to use the MALDI-TOF MS to detect the associated Rickettsia in ticks including Rickettsia conorii and R. slovaca, two human pathogens transmitted by Rhipicephalus sanguineus and respectively Dermacentors marginatus. The spectral variations were obtained between infected and non infected specimens with specific masses related to the tick infection by Rickettsia. The identification technique of not or infected ticks was validated by blind tests. The obtained results allowed concluding that the MALDI-TOF MS could be used in the future to identify the ticks removed from patient, the arthropods vectors and during entomological survey and determine the prevalence of infection of these arthropods
Lo, Cheikh Ibrahima. "Répertoire des bactéries identifiées par Maldi-Tof en Afrique de l'Ouest." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5051/document.
Full textThe Africa bacteria repertory is unfamiliar because the available tools in this region are not allowed its best knowledge. In fact, bacteria are most often identified using culture techniques on simple media and biochemical tests which enable the identification of some common characters. These methods do not facilitate an exhaustive knowledge of the bacterial repertory; consequently they have recently been revolutionized by the systematic use of MALDI-TOF mass spectrometry (MS).In our thesis we used two mass spectrometers, respectively, MALDI-TOF Vitek MS currently installed at Dakar (Senegal) and MALDI-TOF Microflex LT installed in Marseille (France). In addition we have also confirmed that MALDI-TOF is a powerful tool for identifying bacterial species rarely involved in human infectious diseases. Thus in adopting the MALDI-TOF as a first-line tool in bacterial identification before Gram staining or other techniques of phenotypic identifications based on chemical characteristics, we discovered seven new species of bacteria isolated for first time in humans. Microbial identification using MALDI-TOF MS is currently feasible in Africa. Its performance and effectiveness in routine diagnosis of clinical microbiology laboratories have been proven. It is necessary either to increase the installation of MALDI-TOF, or establishing a network around a shared MALDI-TOF platform between several structures located in the same area, especially in the underdeveloped countries of Africa amortization of investment costs of the device, because it allowed reducing the time of reporting results and indirectly facilitating better care for patients
Keller, Bernd Oskar. "Nanoliter chemistry combined with microspot MALDI TOF MS for sensitive protein and peptide characterization." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60307.pdf.
Full textÅkerman, Anna, and Refel Sayfawi. "Etablering av MALDI-TOF MS och webbaserad referensdatabas för identifiering av dermatofyter och mögelsvamp." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-40343.
Full textThe purpose of this study was to establish Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry(MALDI-TOF MS) and the online database Mass Spectrometry identification platform(MSI) as a method for identification of dermatophytes and molds. The fungi were incubated 3 or 6 days aerobic in 30°C on Sabouraud dextrose agar. Two different extraction methods were used before analysis with MALDI-TOF MS. Spectra analyzed with Flexcontrol version 3.4 resulted in score values. The same spectra was later sent for analysis with MSI and the result obtained was seen as probability in percent. Of the original 23 samples a total of 22(95,6%) samples were identified after 3 or 6 days of incubation and by extraction method 1 or 2. The MSI database was more comprehensive than the internal database, but did not use the current fungi names. The necessity of species identification can be questioned, since dermatophytes and molds within the same genera is treated the same way. Species identification for immunosuppressed patients could however be significant. The study was successful and the methods will be applied within a near future in the Clinical Microbiology laboratory in Halmstad.
Barreiro, Juliana Regina. "Identificação direta de microrganismos causadores de mastite por espectrometria de massas." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-25082015-165957/.
Full textThe purpose of the present study was to evaluate the technique of mass spectrometry by desorption / ionization assisted laser array time-of-flight (MALDI-TOF MS) for the direct identification in milk samples (no microbiological culture) of mastitis causing bacteria. Therefore, we carried out two experiments (1 and 2). In experiment 1, we determined the diagnostic sensitivity of MALDI-TOF MS technique for the direct identification in milk samples of Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae, Streptococcus dysgalactiae and Escherichia coli. Experimental contamination of S. aureus, S. uberis, S. agalactiae, S. dysgalactiae and E. coli in samples of milk to a concentration of 103-109 cfu/mL were performed. The contaminated milk samples were processed using kit Maldi Sepsityper® (Bruker Daltonics) and subjected to bacterial lysis protocol for analysis by MALDI-TOF MS. Mass spectra were collected in the mass range of 2000-20000 m/z and were analyzed by MALDI Biotyper 3.0 software (Bruker Daltonics) with default settings to obtain bacterial identification. Direct identification of mastitis causing pathogens from milk samples was possible at ≥106 cfu/mL for S. aureus, ≥107 cfu/mL for E. coli and ≥108 cfu/mL for S. agalactiae, S. dysgalactiae and S. uberis. In experiment 2, the objective was to evaluate the effect of pre-incubation of milk samples from mammary quarters with subclinical mastitis on the effectiveness of identification without cultivation, of mastitis-causing pathogens by MALDI-TOF MS. We selected mammary quarter milk samples from all lactating cows on two dairy herds. The milk samples were subjected to analyzes of: a) microbiological culture; b) pre-incubation followed by identification by mass spectrometry directly from milk; c) total bacterial count (TBC). Flow cytometry was used to determine TBC and; to directly identify the mastitis-causing pathogens from milk, fat was separated by centrifugation (10,000 Xg for 10 minutes) and; samples were pre-incubated at 37°C for 12 hours. Subsequently, the skim milk samples were submitted to kit Maldi Sepsityper® (Bruker Daltonics) and to the bacterial lysis protocol for analysis by MALDI-TOF MS. A total of 810 milk samples were analyzed by microbiological culture (reference method), of which 347 showed bacterial growth. Considering all culture positive samples 305 were identified as agents of interest in the direct identification by MALDI-TOF MS method: coagulase negative staphylococci (n = 191), S. aureus (n = 31), S. agalactiae (n = 42), S. uberis (n = 37) and S. dysgalactiae (n = 4). Therefore, 305 samples were directly identified by MALDI-TOF MS, which presented low sensitivity when compared to microbiological culture (Reference method): coagulase-negative staphylococci (14.08%), S. agalactiae (15.25 %), S. uberis (1.69%), S. aureus (6.12%) and S. dysgalactiae (0%). Pre-incubation of milk samples did not increase the sensitivity of the MALDI-TOF MS method directly identify mastitis-causing microorganisms.
El, Hamzaoui Basma. "Identification des arthropodes et pathogènes associés par MALDI-TOF MS et étude des relations entre arthropodes et bactéries." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0696.
Full textThis work focuses on three main parts, a first part presents an epidemiological study of bacteria associated with soft ticks in Algeria, or we identified morphologically and confirmed by molecular biology six species of Argasidae. In addition, looking further we could detect Borrelia hispanica in Ornithodoros occidentalis and Borrelia cf turicatae in Carios Carpensis. On the other hand, in Argas persicus a new genotype of Bartonella spp has been identified as well as a new species of Anaplasmatacea bacteria.A second part evaluates the vectorial capacity of bed bugs to transmit Borrelia recurrentis, the agent of the relapsing fever. For this reason an experimental model of artificial infection of Cimex lectularius by Borrelia recurrentis has been developed, to study the presence of bacteria in feces. In this model, four approaches were used: qPCR, fece’s culture, FDA (Fluorescein Diacetate) and fece’s inoculation to mice. Immunofluorescence was also used to detect the location of the bacteria in the body of the bed bug. We confirmed that bed bugs acquire the bacteria and excrete live microorganisms in the feces. They can be considered as potential vector of Borrelia recurrentis.The third part is an assessment of the capacity of MALDI-TOF MS to identified fleas, bed bugs and associated pathogens. This innovative tool, which has revolutionized medical entomology and has shown its efficiency to identify several species of arthropods, has also been able to distinguish between infected and uninfected fleas and bugs, and even distinguish between fleas and bugs infected by the same species of bacteria
Jacob, Anette. "Darstellung massenmodifizierter 2',3'-Didesoxynucleosid-5'-Triphosphate für die DNA-Analyse mittels MALDI-TOF-MS." [S.l. : s.n.], 1999. http://www.sub.uni-hamburg.de/disse/89/JACOB.PDF.
Full textSchibur, Stephanie. "Qualitativer und quantitativer Nachweis von Bestandteilen der extrazellulären Matrix des Knorpels mittels MALDI-TOF MS." Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-134850.
Full textNiederfeilner, Elisabeth Isabel [Verfasser], Uwe [Akademischer Betreuer] Frank, and Klaus [Akademischer Betreuer] Biehler. "Infektionsepidemiologische Typisierung MRSA-Isolate mit Hilfe des MALDI-TOF MS im Vergleich zu Spa-Typing." Freiburg : Universität, 2017. http://d-nb.info/1148265724/34.
Full textMarques, Lygia de Azevedo. "Aplicação de tecnicas avançadas de espectrometria de massas em ciencias de alimentos e perfumaria." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248689.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: Neste trabalho aplicamos técnicas avançadas de espectrometria de massas, (MALDI-TOF e ESI-MS) na análise de micotoxinas em alimentos e na tipificação e verificação de fraudes em perfumes. Aplicamos a técnica MALDI-TOF em análises de micotoxinas, e esta mostrou excelente desempenho nas análises de aflatoxinas e ocratoxina e vantagem sobre a técnica de escolha atual, o método ELISA. Esta vantagem é principalmente maior especificidade através de maior exatidão em medidas de massas e, portanto, maior confiabilidade. O Planejamento de experimento foi uma ferramenta valiosa para obtenção das melhores condições e estudo dos parâmetros de interferência. O limite de detecção encontrado para a técnica foi da ordem de 25 pg para aflatoxinas e de 1 ng para ocratoxina, com perspectiva de melhoria através de aumento da massa amostral em estudos futuros para adaptação da metodologia de extração na matriz de interesse à técnica MALDI-TOF. A técnica ESI-MS foi utilizada para a tipificação e detecção de perfumes proporcionando, através da análise de componentes principais (PCA), a diferenciação com segurança entre perfumes originais, falsos e inspirados, utilizando como indicadores componentes polares não majoritários característicos de cada categoria avaliada. Este estudo abre caminho para que esta técnica seja utilizada na avaliação de perfumes que estão sob suspeita de falsificação com auxilio de uma biblioteca de "fingerprint" de perfumes por ESI-MS. O emprego da técnica de MALDI-TOF também é uma opção vantajosa para o monitoramento da qualidade de grãos quanto a presença de toxinas indesejáveis, bem como ameaças de bioterrorismo.
Abstract: In this work we applied advanced mass spectrometry techniques (MALDI-TOF and ESI-MS) to micotoxin analysis in food and for the typification and detection of counterfeit perfumes. MALDI-TOF was applied to micotoxin analysis, which showed excellent performance for the analysis of aflatoxins and ochratoxin with advantage over the current technique of choice, the ELISA method. This advantage is mainly its greater specifity due the exactness of the measurements, therefore with higher reliability. The surface analysis was a valuable tool to attain the best conditions and study the interference of several parameters. The detection limit found for the technique was 25 pg for aflatoxins and 1 ng for ochratoxins, with perspective of improvement through increase of the sample mass in future studies for adaptation of the methodology of extration in the matrix of interest for the MALDI-TOF technique. The ESI-MS technique was used for typification and detection of counterfeit perfumes, providing, through principal component analysis (PCA), the characterization of original, counterfeit and inspired perfumes, using as minoritarian polar compounds as diagnostic ions of each perfume category evaluated. We envisage that the method can be used to establish a ESI-MS fingerprinting library of perfumes for comparison with those from samples under investigation, and that such a library could be updated constantly by the addition of ESI-MS of new perfumes even before they are commercially released. MALDI-TOF technique is also an advantageous option for the monitoring of crop quality relating to the presence of undesirable toxins, as well as bioterrorism threats by micotoxin poisoning.
Mestrado
Quimica Analitica
Mestre em Química
Rasamoelina, Tahinamandranto. "La chromoblastomycose et la sporotrichose à Madagascar : actualités épidémiologiques, cliniques et diagnostiques." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAS028.
Full textChromoblastomycosis (CBM) and sporotrichosis (SPT) are chronic subcutaneous or cutanéo-lymphatic infections found mostly in tropical and subtropical regions. Studies carried out by the Institut Pasteur of Madagascar between 1955 and 1994 provided an inventory of the number of cases of CBM and identified this country as the leading focus of this mycosis worldwide. Mean incidence was estimated at about 0.5/100,000 inhabitants at the time. No new data have been obtained to update the epidemiological situation. About SPT, only sporadic cases have been reported in Madagascar, due to the absence of specific surveillance. CBM is usually caused by dematiaceous fungi, principally Fonsecaea spp. and Cladophialophora spp. The causal agent of SPT is Sporothrix schenckii, a dimorphic hyphomycete.The objectives of this study was to update the data on epidemiology and to evaluate the current burden of these two fungal infections. In addition, we aimed to set up a durable local bio-clinical network and to implement molecular tools to ensure reliable species identification (PCR, sequencing, mass spectrometry).A prospective study, involving the recruitment of patients with suspect lesions was undertaken from March 2013 to June 2017. Patients were included in the dermatology department of the univerity hospital of Antananarivo and through field campaigns in rural areas. Clinical samples were collected and analyzed with conventional mycological methods and molecular tools. Classification of the cases was achieved by the confrontation of mycological and clinical features.Among the 148 patients (mean age 41; male 75.0%): 63 SPT cases (42.5%) and 50 CBM cases (33.8%) were diagnosed. The highest annual incidence of CBM was estimated at 0.38/100,000 inhabitants in the Sava region located to the north. At the district level, the peak incidence was 1.12/100,000 at Anosibe An’Ala, eastern part of the country. Whereas CBM predominated at the periphery of the island, SPT was surprinsgly concentrated in the highlands where the mean incidence was 0.17/100,000 inhabitants. The incidence in the whole country was 0.07/100,000. SPT likelihood of infection was higher in young (<18 years) and the cutaneo-lymphatic forms of the upper limbs were the most frequent. For CBM, farmers and service workers were at high risk and the lesions were mostly (82.9%) located to the lower limbs. The mycological analyses revealed 63 strains of Sporothrix schenckii, 7 of Cladophialophora carrionii, 29 of Fonsecaea sp including 22 F. nubica. F. nubica identification corrected the one of F. pedrosoi previously found in Madagascar, highlighting the need for a molecular analysis of the strains.This is the first study describing human SPT in Madagascar. The SPT burden can now be considered as moderate instead of low as it was described before. It reveals an unexpected concentration of the patients in the central highlands. CBM burden was found at a high level, regrettably similar to the one described 20 years ago, showing the lack of control of this infection. The implementation of a durable bio-clinical network and of the new molecular tools (PCR et le MALDI-TOF MS) developed in this work will easy the development of surveillance programs, especially as the WHO recently added CBM in the neglected tropical diseases list. The network that was built for this work will be used for further therapeutic trials on new schedules of treatment, new drugs or new formulations as well as genetic studies about predisposing factors of CBM and SPT and others deep fungal infections that are still neglected in Madagascar. Yet, an environmental survey is ongoing to describe the sources of contamination
Nebbak, Amira. "Développement expérimental et application sur terrain d'outils innovants pour l'identification des arthropodes." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0605.
Full textHematophagous arthropods such as mosquitoes, ticks, and fleas are of significant importance in public health because of their ability to transmit major diseases to humans and animals. Vector control and epidemiological vector surveillance are essential in the strategy of combating vector-borne diseases. The latter is successful only by a correct and precise identification of the vectors. Thus in this work, we have developed and improved the protocols of samples preparation for the identification of adult mosquitoes and their aquatic stages, ticks, and fleas by MALDI-TOF MS. This tool has been already distinguished as being reliable for the arthropods identification. The second part of our work consisted in the application of these protocols on mosquito larvae collected in the field during an entomological investigation carried out in the city of Marseille. In this study, the relevance and reliability of MALDI-TOF MS for the identification of mosquito larvae collected in the field were verified. Finally, we carried out the inventory of the viral communities of three mosquito species collected in Marseille by metagenomics, which revealed the presence of numerous new viruses. All the results presented in this thesis emphasize that the use of innovative tools such as MALDI-TOF MS and metagenomics to study vectors and the agents they carry is a promising strategy that will contribute to the knowledge of zoonotic transmission cycles and the potential risks of the emergence of vector-borne diseases in human populations
Jemmali, Zaïneb. "Développements méthodologiques en TLC/MALDITOF MS et GC/MS pour l’analyse des composés terpénoïdes présents dans les résines végétales." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2061/document.
Full textResins are hydrocarbon secretions of many plants and well known for their protective benefits. They have been used as raw materials for a wide range of applications (pharmaceutic, cosmetic and artistic). Plant resins are complex mixtures of organic substances mainly terpenoid compounds which constitute the most abundant and structurally diverse group of plant secondary metabolites. The chemical characterization of this material results in long and difficult separation due to the wide range of polarity and volatility of its constituents. The aim of this work was to develop new analytical approaches to improve the identification of resins certifying their origin and ensuring the quality control. For that purpose two analytical methods were selected: TLC and GC approaches hyphenated to mass spectrometry. TLC-1D and TLC-2D allow a rapid screening and first visual differences of resins. The innovating TLC coupling to MALDI-TOF-MS gives a clear identification of major markers (triterpenic acids). In order to have complementary information about the composition of resins, a gas chromatography-mass spectrometry (GC-MS) method was developed to analyze volatile to non-volatile compounds. The various stages of optimization were based on experimental design and statistical (PCA and HAC) approaches. For closely related resins, a quantitative approach was investigated based on a complete validation for major markers. This work allows the development of two complementary techniques that give a powerful approach for fast and reliable differentiation of various resins even the closest ones
Jäger, Jakub. "Biotypizácia kvasiniek skupiny Cryptococcus laurentii hmotnostnou spektrometriou." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217092.
Full textMaurer, Katja. "Oral brush biopsy analysis by MALDI-ToF Mass Spectrometry for early cancer diagnosis." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-116691.
Full textKnoop, Nicolas. "Identifizierung von Enterobacteriaceae und Nonfermentern mittels MALDI-TOF MS unter besonderer Berücksichtigung von multiresistenten und darmpathogenen Erregern." Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-158579.
Full textSartori, Sergio Birello. "Potencial metabólico de fungos endofíticos de plantas do gênero Anthurium da Ilha de Alcatrazes." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-29112016-141525/.
Full textEndophytic fungi are present in plants in various environments and produce compounds with wide chemical properties and applications, both in the medical and in agronomic field. However, much remains to be investigated about their biotechnological potential, especially in unexplored places. Islands have a particular and highly vulnerable environment, making them promising sites in search of unusual or endemic organisms. Thus, this work represents the isolation and chemical and biological study of endophytic fungi isolated from 2 species of plants of the genus Anthurium of Alcatrazes island-SP. For this, leaf fragments from plants A. loefgrenii (HRCB 46467) and A. alcatrazense (HRCB 46465 - endemic plant from the Island) were inoculated onto 10 culture media with different composition, resulting in the isolation of 106 endophytic fungi. Three strains were selected to be studied through chemical analysis by MALDI-TOF-MS and bioassay against phytopathogens. These were identified by morphological and molecular techniques as Penicillium citrinum (P2MSF2F3), Penicillium simplicissimum (P210-4F2) and Aureobasidium melanogenum (P7AF2F3). In the study of secondary metabolites of P. citrinum it was isolated the compound citrinin, which showed inibitory activity against the plant pathogens Colletotrichum gloeosporioides (MIC= 125 μg mL-1), Colletotrichum lindemuthianum (MIC= 0.48 μg mL-1), Phomopsis sojae (MIC= 250 μg mL-1) and Fusarium oxysporum f. sp. phaseoli (MIC= 125 μg mL-1). Other fraction obtained from the metabolic extract of P. citrinum (F3a3 fraction and citrinin), showed inibitory activity (100% inibition) to Leishmania infantum promastigotes. In the study of secondary metabolites of P. simplicissimum it was obtained F2b fraction, active against L. infantum (100% inhibition), which were isolated andrastin A and penicisoquinoline compounds, the first report of its production for this species, as well 5 unidentified compounds. In the study of secondary metabolites from A. melanogenum was isolated the methyl-orsellinate compound, first reported for this fungus. From the same strain was obtained F1d2l fraction, active against L. infantum (100% inhibition), from which were isolated 2 unidentified compounds. This is the first report of fungi isolated from Alcatrazes Island anthuriums and the study of their secondary metabolites. This study presents contribution to knowledge of endophytic fungi and their metabolic potential with applications in the medical and agronomic fields.
Li, Xin. "Comparative evaluation of the extraction and analysis of urinary phospholipids and lysophospholipids using MALDI-TOF/MS." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/265182.
Full text新制・課程博士
博士(医学)
甲第23410号
医博第4755号
新制||医||1052(附属図書館)
京都大学大学院医学研究科医学専攻
(主査)教授 村川 泰裕, 教授 長尾 美紀, 教授 柳田 素子
学位規則第4条第1項該当
Doctor of Medical Science
Kyoto University
DFAM
Teixeira, Renata Roland. "Identificação das glicoproteínas da geléia real de Apis mellifera L. por análise em MALDI-TOF MS." Universidade Federal de Uberlândia, 2007. https://repositorio.ufu.br/handle/123456789/15902.
Full textThe royal jelly (RJ), a secretion produced by the hipopharingeal and mandibular glands of the nurse honeybees, have a variety of pharmacological activities, aside of being necessary for the castes differentiation and the queen Apis mellifera longevity. To identify the N-glycoproteins of two samples of RJ provinient from distinct origin and conditions, we used the concanavalin A affinity chromatography (ConA) associated to the mass spectrometry. The investigated samples of RJ were the brazilian RJ (GRB), produced experimentally in local apiary, and the Chinese RJ (GRC), mattered from China and commercially available. The protein profile in SDS-PAGE 1D was characteristic for GRB and GRC. The N-glycoproteins fractions eluted from the ConA column had presented nine polypeptides for GRB and 12 for GRC, with relative molecular mass (Mr) varying between 130 and 15 kDa. It was observed that the immediately aftercollects freezing of the GRB did not inhibited the appearance of bands with Mr lesser than 49 kDa. A total of 21 bands was excised from gel and digested with tripisin for analysis in MALDI-TOF MS. The bioinformatic analysis revealed that all the 16 proteins identified in the GRB and GRC samples belong to the A. mellifera apalbumins family (Apa-1, Apa-2 and Apa-3). The Apa-2 was the protein that had greater prevalence between the N-glycoproteins of the RJ, presenting Mr varying between 110 and 25 kDa. The fact that the Apa-2 had been identified with distinct Mrs can be related to glycosilation, oligomerization or degradation of this apalbumin. Therefore, the ConA affinity chromatography associated with the proteomic analysis made possible the identification of three members of the family of RJ main proteins (Apa-1, Apa-2 and Apa-3). Moreover, the comparative study of the GRB and GRC glycoprotein composition suggests similar standard between these samples and can be useful in future studies that evaluate the biological functions of the apalbumins pos-translational modifications.
A geléia real (GR), uma secreção produzida pelas glândulas hipofaringeal e mandibular das abelhas operárias, possui uma variedade de atividades farmacológicas, além de ser fundamental para a diferenciação das castas e longevidade da rainha de Apis mellifera. Com o objetivo de identificar alguns dos componentes bioativos deste produto da colméia, utilizou-se a cromatografia de afinidade de concanavalina A (ConA) associada à espectrometria de massa para identificar as N-glicoproteínas de duas amostras de GR obtidas de origem e condições distintas. As amostras de GR investigadas foram a GR brasileira (GRB), produzida experimentalmente em apiário local, e a GR chinesa (GRC), importada da China e disponível comercialmente. O perfil de proteínas em SDSPAGE 1D foi característico para GRB e GRC, com um maior número de polipeptídeos para GRC. As frações das N-glicoproteínas eluídas da coluna de ConA apresentaram nove polipeptídeos para GRB e 12 para GRC, com massa molecular variando entre 130 e 15 kDa. Observou-se que o congelamento imediatamente pós-coleta da GRB não impediu o aparecimento de polipeptídeos com Mr menor que 49 kDa. Um total de 21 bandas foi excisado do gel e digerido por tripsina para análise em MALDI-TOF MS. Para cada perfil de massa dos peptídeos (PMF) obtido, realizou-se a busca em banco de dados utilizando-se o software Mascot. Esta análise revelou que as 16 proteínas identificadas nas amostras de GRB e GRC pertencem à família das apalbuminas (Apa-1, Apa-2 e Apa-3) da abelha A. mellifera. A Apa-2 foi a proteína que teve maior prevalência entre as N-glicoproteínas da GR, apresentando Mr variando entre 110 e 25 kDa. O fato da Apa-2 ter sido identificada com Mrs distintas pode estar relacionado a fenômenos de glicosilação, oligomerização ou degradação desta apalbumina. Portanto, a cromatografia de afinidade de ConA associada a análise proteômica possibilitou a identificação de três membros da família das principais proteínas da GR (Apa-1, -2 e -3). Além disso, o estudo comparativo da composição de glicoproteínas da GRB e GRC sugere padrão similar entre estas amostras e pode ser útil em estudos futuros que avaliem as funções biológicas das modificações pós-traducionais das apalbuminas.
Mestre em Genética e Bioquímica
Motari, Edwin Mwamba. "Structural Studies of Oligosaccharides Attached to Proteins Expressed in Different Organisms and PEGylation of a non-Glycosylated Protein." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274803162.
Full textRodrigues, Naiara de Miranda Bento. "Identifica??o de enterobact?rias atrav?s da t?cnica de MALDI-TOF MS e compreens?o da dissemina??o destes agentes em ambiente de produ??o leiteira." Universidade Federal Rural do Rio de Janeiro, 2016. https://tede.ufrrj.br/jspui/handle/jspui/1213.
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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPQ
Mastitis adversely affects milk production and in general cows do not regain their full production levels post recovery, leading to considerable economic losses. Moreover the percentage decrease in milk production depends on the specific pathogen that caused the infection and enterobacteria are responsible for this greater reduction. These microorganisms are preferentially found in the habitat of animals in places contaminated with feces, urine, clay and also organic beds. Phenotypic tests are among the currently available methods used worldwide to identify enterobacteria; however they tend to misdiagnose the species despite the multiple tests carried out and they can delay the antibiotic therapy by clinic veterinary. On the other hand the MALDI-TOF MS technique has been attracting attention for its precise identification of several microorganisms at species level. In the current study, 183 enterobacteria were detected in milk (n=47) and fecal samples (n=94) collected from cows; also water (n=23) and milk line samples (n=19) collected from a farm in Rio de Janeiro with the purpose to present the MALDI-TOF MS technique as efficient methodology and also as a ?gold standard? to better understand the possible current biochemical errors in enterobacteria identification considering isolates from bovine environments. This proteomic technique confirmed 92.9% (170/183) of the enterobacteria species identified by biochemical tests that showed high sensitivity (> 81%) and specificity (> 89%). The gyrB sequencing was made in eigth from thirteen misidentified enterobacteria and confirmed 100% the MALDI-TOF results, so the proteomic technique was used as a ?gold standard? for this study. The amino acid decarboxylation test made the most misidentifications and Enterobacter spp was the largest misidentified genus (76.9%, 10/13). E.coli was prevalent (83%, 152/183) in all samples and the bovine milk presented the most enterobacteria diversity. The Salmonella sp wasn?t detected in feces bovine samples and all water samples from different points in the farm presented unacceptable microbiological standards. Was identified enterobacteria in milkers hands and nasal cavity also in the milking machines used on the property. These results aim to contribute significantly to the characterization of the Enterobacteriaceae as well in understanding of its spread in dairy production environment , assisting in need diagnostic of possible agents involved in bovine mastitis as well as to implement properly targeted prophylactic measures.
A mastite bovina afeta negativamente a produ??o de leite dificultando a recupera??o dos n?veis de produ??o total das propriedades leiteiras, levando a perdas econ?micas consider?veis. Esta redu??o no percentual da produ??o de leite pode estar associada ao agente patog?nico espec?fico que causou a infec??o, sendo as enterobact?rias frequentemente respons?veis pela mastite ambiental. Estes microrganismos s?o preferencialmente encontrados no habitat normal dos animais como locais que apresentam esterco, urina, barro e camas org?nicas. Os testes fenot?picos est?o entre os m?todos dispon?veis atualmente utilizados para identificar as enterobact?rias; no entanto, eles podem ocasionalmente identitificar erroneamente algumas esp?cies apesar dos m?ltiplos ensaios realizados. Al?m disso, a demora na sua execu??o pode tardar a antibioticoterapia realizada em campo. Por outro lado, a t?cnica de MALDI-TOF MS tem atra?do a aten??o pela sua identifica??o precisa dos v?rios microorganismos em n?vel de esp?cie. No presente estudo, um total de 183 enterobact?rias foram isoladas a partir de amostras de leite (n=47) e fezes colhidas de vacas em lacta??o (n=94); amostras de ?gua (n=23) e na linha de ordenha (n=19) em uma propriedade situada no Rio de Janeiro. A proposta foi utilizar a t?cnica de MALDI-TOF MS como um m?todo eficaz de identifica??o bacteriana de enterobact?rias e descrever a permanencia destes microrganismos no ambiente de produ??o leiteira. A t?cnica prote?mica confirmou 92,9% (170/183) das esp?cies de enterobact?rias identificadas pelos testes bioqu?micos convencionais. O sequenciamento do gene gyrB, realizado em oito das 13 enterobact?rias que apresentaram identifica??o discordante, confirmou em 100% o resultado da t?cnica prote?mica, que foi utilizada como metodologia de refer?ncia no presente estudo. O g?nero Enterobacter foi o mais discordante pelo m?todo bioqu?mico (76,9%, 9/13). A E.coli foi a esp?cie predominante (83%, 152/183) em todas as amostras avaliadas, sendo que o leite bovino apresentou maior diversidade de enterobact?rias. N?o foi detectada a presen?a de Salmonella spp. nas amostras de fezes bovinas e todas as amostras de ?gua dos diferentes pontos de coleta da propriedade apresentaram padr?es microbiol?gicos inaceit?veis. Foram isoladas enterobact?rias das m?os e cavidades nasal dos ordenhadores, bem como nas ordenhadeiras mec?nicas utilizadas na propriedade. Estes dados visam contribuir de forma significativa para a caracteriza??o das enterobacterias bem como para a compreens?o e sua descri??o no ambiente de produ??o leiteira, auxiliando no diagn?stico preciso dos poss?veis agentes envolvidos na mastite bovina bem como na implementa??o de medidas profil?ticas devidamente direcionadas.
Rivas, Becerra Daniel. "Aplicación de MALDI-TOF Imaging y HPLC-MS/MS al estudio de la degradación del polímero policaprolactonadiol en diferentes medios acuáticos." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/461713.
Full textEl agua es esencial para la vida y las actividades del ser humano y de los ecosistemas. El cambio global climático junto al incremento constante de población hace que el desequilibrio entre la demanda de agua y los recursos hídricos disponibles se incremente. Todo ello redunda en un impacto creciente sobre la salud humana y los ecosistemas acuáticos. La caracterización de los sistemas acuáticos incluye tanto aspectos estructurales como funcionales. Entre estos últimos hay que destacar la degradación de la materia orgánica, tanto natural como de origen antropogénico. La ecología de sistemas acuáticos utiliza la pérdida de peso de soportes orgánicos naturales como hojas secas o fragmentos de madera estandarizados expuestos al medio para calcular la pérdida de materia orgánica. Partiendo de esta idea el objetivo principal de esta tesis ha sido introducir más conocimiento químico dentro de la ecología de ríos utilizando una sonda basada en material sintético para estudiar su degradación en ambientes acuáticos, tanto naturales como ingenieriles. El dispositivo contiene un polímero comercial, el cual después de estar expuesto un tiempo en diferentes entornos acuáticos se recoge y se analiza su degradación utilizando técnicas avanzadas de espectrometría de masas, como son HPLC-MS, MALDI-TOF/MS y MALDI IMAGING. El capítulo 1 (Introducción) está dividido en tres partes. En la primera se presenta la problemática asociada a la calidad del medio acuático, sus efectos sobre los ecosistemas y se describen sucintamente los procesos bióticos y abióticos de degradación de la materia orgánica y su aplicación en las EDAR. En la segunda parte se realiza una breve descripción de los polímeros, sus usos y degradación, así como las técnicas analíticas que se usan para caracterizarlos. En la tercera parte, se describen las técnicas analíticas de espectrometría de masas empleadas en esta tesis, haciendo énfasis en aquellas que permiten el estudio espacial en dos dimensiones, mediante la correspondiente generación de imágenes (IMAGING). Los objetivos principales de la tesis se detallan en el capítulo 2. En el capítulo 3 se describe la selección de posibles polímeros a utilizar, así como la optimización de los correspondientes métodos de análisis mediante MALDI-TOF/MS. Con el polímero finalmente elegido (policaprolactonadiol 1250) se prepararon sondas poliméricas y se realizaron experimentos de exposición en diversos puntos del río Ebro. Los resultados obtenidos evidenciaron diferentes tipos de degradación. Finalmente, éstos se compararon con los obtenidos en paralelo mediante métodos clásicos, empleando hojas de árbol. Con el polímero seleccionado se realizaron experimentos a escala de laboratorio, que se describen en el capítulo 4, consistentes en la exposición de muestras de polímero durante un tiempo concreto en sistemas acuosos en condiciones estériles, aeróbicas y desnitrificantes. El uso de la novedosa técnica MALDI IMAGING, permitió observar diferencias de degradación a lo largo de la superficie de la muestra entre los tres tipos de condiciones ensayadas, obteniendo imágenes de los iones más interesantes. Así mismo, el tratamiento estadístico de los resultados obtenidos confirmó las imágenes adquiridas. El éxito del experimento anterior a escala de laboratorio, impulsó llevarlo al siguiente nivel y aplicarlo en muestras de aguas residuales. Así pues, las sondas de polímero se instalaron en el reactor secundario de la EDAR del Prat de Llobregat, donde se realiza un tratamiento de nitrificación (aerobio) y uno de desnitrificación (anaerobio). Para analizar las muestras se utilizó la técnica MALDI IMAGING y HPLC-MS para elucidar las estructuras de los compuestos de degradación y establecer los mecanismos de degradación correspondientes productos de transformación en función de las condiciones estudiadas. Finalmente en el capítulo 6 se comenta la discusión general de cada experimento realizado extrayéndose unas conclusiones finales.
Dantas, Vânia Patrícia Gonçalves. "Caracterização polifásica de fungos filamentosos zygomycetes com interesse em biotecnologia ambiental." Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/14995.
Full textSQUEO, VALERIA. "Alterazioni del peptidoma serico di pazienti con tumore renale valutate tramite "label-free" (nLC-ESI-MS/MS) e "peptide profiling" (MALDI-MS/MS)." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/43783.
Full textŠvecová, Natália. "Kvasinky polyfyletického rodu Cryptococcus - ich vlastnosti a výskyt v prírode." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-414131.
Full textMatti, Reman. "JÄMFÖRELSE MELLAN PREPARATIONSMETODER AV POSITIV BLODODLING INFÖR DIREKT IDENTIFIERING MED MALDI-TOF MASS SPEKTROFOTOMETRI." Thesis, Malmö universitet, Fakulteten för hälsa och samhälle (HS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26085.
Full textAbstract: Sepsis (blood poisoning) is a life-threatening condition caused by bacteria or fungi entering the bloodstream. Pathogens often again access through the kidneys, lungs or wounds in damaged skin. Symptoms include fever, chills and general feeling of illness. Positive blood cultures are prepared and analyzed with Matrix assisted laser desorption ionization time-of-flight (MALDI-TOF MS) prepared samples are mixed with matrix and then irradiated with laser beam. The laser beam will be directed to each position in the MALDI plate that causes the proteins in the sample to ionize and move towards a detector. The protein pattern is presented in a spectrum that is compared with a reference spectrum of known bacteria / fungi, stored in a database. In addition, a score value was obtained on how well the sample is aligned to the reference sample. The aim of this study was to compare three methods in order to achieve the best score value for identification to species level. The time factor was also important. The preparation methods include purification of blood removing red blood cells and other particles that interfere with MALDI analysis. The methods were compared with the current Saponinmethod. The results of two methods (Ferroni and Huang) were not satisfactory and further comparison was interrupted after two experiments. A commercial kit Sepsityper with extraction gave good results with 79 % identification to species level. Corresponding results for the current Saponin-method was 33 %. In conclusion, the Sepsityper-extraction-method was superior to the current Saponin-method. The method was robust, user-friendly, rapid and gave good results from both gramnegative and grampositive bacteria.
Thiel, Juliane. "Charakterisierung von Viridans-Streptokokken in kariösem Dentin durch biochemische Identifizierung, MALDI-TOF-MS-Analyse und speziesspezifische PCRs." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-100280.
Full textGabriel, Stefan Johannes [Verfasser], Ulrich [Gutachter] Panne, Clemens [Gutachter] Schwarzinger, and Klaus [Gutachter] Rademann. "Entmischungsphänomene in lösemittelbasierenden MALDI-TOF MS Probenpräparationen / Stefan Johannes Gabriel ; Gutachter: Ulrich Panne, Clemens Schwarzinger, Klaus Rademann." Berlin : Bundesanstalt für Materialforschung und -prüfung (BAM), 2015. http://d-nb.info/1122741332/34.
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