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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
661

Selection of a calcium-dependent IgG1-binding protein domain

Rönning, Sanne January 2020 (has links)
Standard purification processes in large scale antibody production are largely dependent on Protein A chromatography. Protein A binds specifically to many subclasses of IgG with high affinity. However, in order to elute the proteins, the pH needs to be lowered. Since lowering of the pH can be detrimental to some antibodies, a milder purification process is of great interest. A variant of Protein A, called ZCa, has previously been engineered to bind to IgG in a calcium-dependent manner. The antibody binds to ZCa when calcium is present and releases when calcium is removed. For the IgG1 subclass, the elution still requires a slight lowering of the pH, which is why there is room for improvement of the molecule. A phage display selection has been performed with the aim to obtain calcium-dependent IgG1 binders that are able to release the antibodies upon calcium depletion at neutral pH. In addition, an attempt on increasing the alkaline stability of the binders was made. Sequence analysis of the selection output showed almost no indications of increased alkaline stability. Instead, M13K07 helper phages were exposed to new selections for increased alkaline tolerance which might be useful in future phage display selections. Even though the binders selected for in this project did show some promising characteristics, none of them were able to elute upon calcium depletion at neutral pH as aimed for. However, one of the variants did show promising results during most of the performed characterizations. Most interestingly, the elution properties of this variant could indicate a higher calcium-dependence in the interaction with the target than that of ZCa, although further characterizations need to be performed in order to draw any conclusions about possible improvements of this protein domain.
662

Pathological Mechanisms of Sarcomere Mutations in the Disease Hypertrophic Cardiomyopathy : A Review

Bohman, Lova January 2021 (has links)
Hypertrophic cardiomyopathy is a heart disease that is characterized by an enlarged heart muscle. Mutations to sarcomere proteins in the muscle fibers give rise to the disease, and this review aims to compile the mechanisms by which the mutations cause the disease phenotype. β-myosin heavy chain mutants affect the thick filament structure and contraction velocity of the muscle. Mutations to the myosin-binding protein C produces truncated proteins with decreased expression in the cells. Troponin T mutants cause myofibrillar disarray, alters affinity to α-tropomyosin, and are linked to a higher risk of sudden death. Troponin I is an unpredictable mutant that needs to be further researched but is thought to cause regulatory problems. Mutations to α-tropomyosin and the regulatory myosin light chain both affect the Ca2+-affinity of the proteins and leads to contractile problems. Hypercontractility as a result of the mutations seems to be the primary cause of the disease. Hypertrophic cardiomyopathy is linked to sudden death, and factors such as a family history of sudden death, multiple simultaneous mutations, unexplained syncope, non-sustained ventricular tachycardia, abnormal blood pressure response and extreme hypertrophy (>30 mm) heightens the risk of a sudden death. An increased knowledge about the disease will aid in the mission to better the treatments for the affected, but further investigation of pathological pathways needs to be performed.
663

Development of a new quantitative PCR analysis method for HIV-1

Schöldström Degenne, Jacob January 2021 (has links)
På grund av planerat tillverkningsstopp av instrumenten som används idag på Octapharma AB, så syftar detta projekt till nyutvecklingen av en kvantitativ PCR analysmetod för detektion av HIV-1 i human blodplasma, genom TaqMankemi. Projektet inkluderade design, testning och utvärdering av olika set av primer och probe sekvenser. För att säkerställa specificiteten hos metoden designades primrarna och proberna för att vara komplementära till olika konservativa regioner av HIV-1:s genom. Primer och probe set:en (P/P) testades både individuellt och kombinerat i spädningsserier och genotypspaneler. Analyserna visade att det inte fanns någon korrelation mellan felmatchning av P/P och referenssekvenser hos subtyper, och detektionsnivå. När P/P testades i kombination hittades falsk-positiva signaler i negativa kontroller (4 falsk-positiva signaler; n= 106). Detta åtgärdades genom att utesluta specifika prober(0 falsk-positiva signaler; n= 152)(p = 0,030, Fisher’s exact test). Kombinationen av primer och prober, med någraprober uteslutna, hade en högre detektionsnivå för HIV-1 subtyper än de individuella set:en (29 positiva prover vs 23.5; n= 64), och lyckadesäven detektera åtminstone ett positivt prov hos varje subtyp A, B, C, D, AE, F, G och H. Avsaknaden av korrelation mellan felmatchning av P/P och detektionsnivå, visar på att orsaken av den suboptimala detektionsnivån av subtyper var inte på grund av antalet felmatchningar mellan primer och probe set:en till målsekvenserna. Den högre specificiteten vid kombination av P/P indikerar även att primrar och prober som riktar in sig på olika regioner avHIV-1 genomet ytterligare ökar specificiteten och detektionsnivån hos metoden. / As a result of future instrument discontinuation by Octapharma AB’s manufacturers, this project sought to develop a new quantitative PCR analysis method for the detection of HIV-1 in human blood plasma using TaqMan chemistry. The project included the design, testing and statistical analysis of different sets of novel primer and probe sequences. To ensure specificity, the primer and probe sequences were designed to target conserved regions of the HIV-1 genome. The primer and probe sets were tested both individually and in combination in dilution series and genotype tests. Linear regression analyses showed no correlation between mismatches between the primer and probe sets and the subtype reference sequences tested, and detection rate. When the primer and probe setswere tested in combination, false positive signals were obtained in negative control samples (4 false positive signals; n= 106). However, this obstacle was overcome by the omission of certain probes, resulting in no false positive signals (0 false positive signals; n= 152)(p = 0.030, Fisher’s exact test).The combination of primer and probe sets, with certain probes omitted, had an increased HIV-1 subtype detection rate compared to the individual P/P (29 positive samples detected versus 23.5; n= 64), and were also able to detect at least one positive sample from each of the HIV-1 subtypes A, B, C, D, AE, F, G, and H. The absence of correlation between primer and probe set mismatch and detection rate, suggests that the cause of the suboptimal detection rate of the subtypes was not the result of primer and probe set mismatch to the target sequences. The increased subtype detection rate upon combining the P/P also indicates that targeting different region of the HIV-1 genome further improves the detection rate and specificity of the method.
664

Identification of changes in biomarkers relevant for breast cancer biology occurring in a novel 3D-Biosilk model

Ståhl, Emmy January 2021 (has links)
Bröstcancer är den vanligaste formen av cancer som drabbar kvinnor. Det är en heterogen och komplex sjukdom som består av flera undergrupper, var och en med distinkt morfologi och kliniska implikationer [1]. För att modellera och studera cellbiologi, vävnadsmorfologi, molekylära mekanismer och läkemedels effekter används cellkulturer [2]. Idag är tvådimensionella (2D) modeller fortfarande den mest använda metoden för att odla celler in vitro [3]. En nackdel med 2D-modeller är att mikromiljön i dessa modeller inte imiterar in vivo strukturen av tumörer och vävnader, då de saknar tre dimensionella (3D) cell-cell och cellextracellulär matrix (ECM) interaktioner [2]. På grund av nackdelarna med 2D-modeller, har 3D-modeller blivit mer intressanta som alternativ för att lösa behovet av en pålitlig preklinisk modell för läkemedelstestning och för studier av cancerbiologi. För att utveckla ett redskap som är relevant för cancerforskning etablerar professor My Hedhammars laboratorium en 3D-modell av bröstcancer. I en sådan ny modell används Biosilk som byggnadsställning för att odla odödliga cellinjer som är representativa för de tre huvudklasserna av bröstcancer (i.e. MCF-7 (luminal-lik), SKBR-3 (HER2-överuttryckt) och MDAMB- 231 (trippel-negativ)). Eftersom transkriptions signaturer kan användas för att klassificera och studera bröstcancer är det viktigt att undersöka om och hur tillväxt i 3D-Biosilk kan påverka genuttrycksprofiler. Hypotesen som testades i denna studie var om cellkulturer i 3DBiosilk kan ha signifikanta skillnader i uttryck av biomarkörer, relevanta för bröstcancerbiologi, vid jämförelse av samma cellinje kultiverad i 2D. För att testa detta utvärderades kvalitén och reproducerbarheten av 3D-Biosilk konstruktionen med hjälp av olika kvalitetstester. Strukturen granskades med brightfield mikroskopi, arean av konstruktionen mättes med ImageJ, infärgning med phalloidin bekräftade cellnärvaro och cellvidhäftning till modellen. Alamar blue utfördes för att bedöma den cellulära metaboliska aktiviteten i modellen. Förändringarna av målgenernas genuttryck undersöktes med kvantitativ omvänd transkription PCR (RT-qPCR) och detta påvisade en statistiskt signifikant skillnad i genuttrycket beroende på om cellerna odlats i 2D- eller 3D-Biosilk modeller. I cellinje MDA-MB-231 hittades tre gener, i cellinje SKBR-3 hittades två gener och i cellinje MCF-7 hittades fyra gener. Genuttrycket för en av dessa gener i cellinje MCF-7, som var kultiverad i 3D-Biosilk, var nedreglerad (i.e. ZO-1). Detta kunde valideras på proteinnivå med immunofluorescens. Sammanfattningsvis, celler odlade i 3D-Biosilk visar på en mer aggressiv fenotyp. / Breast cancer is the most common cancer among women. It is a heterogenous and complex disease composed of several subtypes, each with distinct morphological and clinical implications [1]. To model and study cell biology, tissue morphology, molecular mechanisms and drug actions, cell cultures are canonically used [2]. Today two-dimensional (2D) models are still widely the preferred method for culturing cells in vitro [3]. A drawback with 2D models is that the microenvironment in these models does not mimic the in vivo structure of tumors and tissues, lacking three-dimensional (3D) cell-cell and cell-extracellular matrix (ECM) interactions [2]. Due to the disadvantages of 2D models, 3D cultures have become an increasingly interesting alternative to solve the need for a reliable preclinical model for drug testing and the study of cancer biology. To develop a relevant tool for cancer research, the laboratory of professor My Hedhammar is currently establishing a 3D model of breast cancer. In such novel model, Biosilk is used as scaffold to grow immortalized cell lines representative of the three major classes of breast cancer (i.e. MCF-7 (luminal-like), SKBR-3 (HER2-overexpression) and MDA-MB-231 (triplenegative)). Since transcriptional signatures can be used to classify and study breast cancers, it is important to investigate if and how growth in 3D-Biosilk can impact gene expression profiles. The hypothesis tested in this study was that cells cultured in 3D-Biosilk have differences in expression of biomarkers relevant to breast cancer biology, when compared to the same cell lines cultured in 2D. To examine this, 3D-Biosilk models were created and evaluated to ensure their quality and reproducibility, for instance, the scaffold structure was monitored by brightfield microscopy, the construct’s area was measured with ImageJ, staining with phalloidin confirmed the presence of cells as well as their attachment to the construct, and Alamar blue was used to assess the cellular metabolic activity. Differences in gene expression of target genes were investigated using reverse transcription quantitative PCR (RTqPCR), which revealed statistically significant changes depending on whether the cells were cultivated in 2D or a 3D-Biosilk model. For cell line MDA-MB-231 three genes were found, for SKBR-3 two genes were found and for MCF-7 four genes were found. The expression of one gene which was found downregulated in MCF-7 cultured in 3D-Biosilk (i.e. ZO-1) was validated at protein level by immunofluorescence. In conclusion, cultivating cells in 3D-Biosilk indicates a more aggressive phenotype.
665

Potency Analysis of Mesenchymal Stromal Cells Towards Innate and Adaptive Immune Cells

Garbers, Linn January 2023 (has links)
Studien utvärderar egenskaper hos mesenkymala stromaceller (MSC) i passage 2 och 3. I ett samarbete mellan Cellcolabs och Karolinska Institutet (KI) genomfördes projektet med Katarina Le Blancs forskargrupp. Genom att studera membranmarkörer från tre friska MSC-donatorer, tillsammans med deras förmåga att differentiera till osteoblaster, adipocyter och kondrocyter, samt deras förmåga att inhibera profileringen av CD8+ och CD4+ T-lymfocyter, och slutligen deras möjlighet att öka uttrycket av Indoleamine 2,3-dioxygenase 1 (IDO1) och interleukin 6 (IL6), kunde en jämförelse mellan passage 2 och 3 göras. I korta drag kunde enbart en tydlig skillnad göras mellan de två passagerna. Skillnaden sågs i förmågan att differentiera till osteoblaster, där passage 3 inte kunde prestera på samma nivå som passage 2. Utöver detta var resultaten för de två typerna jämförbara och antydde inte till några större förändringar mellan passage 2 och 3. För att stärka tillförlitligheten av resultatet bör dock fler MSC-donatorer jämföras. / The study evaluates the characteristics and consistency of mesenchymal stromal cells (MSCs) in two different passages, specifically 2 and 3. In a collaboration between Cellcolabs and Karolinska Institutet (KI), the project was conducted with Katarina Le Blanc’s research group. Through studying the surface expression on cells from three distinct MSC donors, along with their differentiation ability into osteoblasts, adipocytes and chondrocytes, their capability to suppress the proliferation of CD8+ and CD4+ T lymphocytes, and finally their possibility to increase the expression of indoleamine 2,3-dioxygenase 1 (IDO1) and interleukin 6 (IL6), a comparison between passage 2 and 3 could be done. It was seen that a clear distinction could be made between the two passages while looking at their ability to differentiate into osteoblasts. The remaining results showed comparable outcomes between passage 2 and 3, suggesting minor changes with the increased passage number. However, to strengthen the reliability of the outcome, more MSC donors should be compared.
666

Towards time-resolved cryo-EM of SARS-CoV-2 replication-transcription complex and Staphylococcus aureus DNA gyrase

Králová, Anna January 2023 (has links)
Time-resolved cryo-EM has already provided ground-breaking discoveries in various fields, including structural biology, biochemistry, and drug development. Compared to traditional structural biology methods where mostly stabilized conformations are reconstructed, the main advantage of time-resolved cryo-EM is its ability to capture dynamic processes in biological samples at near-atomic resolution, which allows for studying biological structures as they change and interact in real-time. In this project, I focused on the expression and purification of the individual proteins of two dynamic molecular complexes – Staphylococcus aureus (S. aureus) DNA gyrase and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) replication-transcription complex – and attempted to assemble them into their functional forms for cryo-EM imaging.  Both of these complexes are interesting drug targets as they play an essential role in nucleic acid replication. The function of DNA gyrase is to modulate DNA supercoiling, facilitate DNA replication, and resolve intertwined DNA molecules. The replication-transcription complex of SARS-CoV-2 comprises, among other proteins, the RNA-dependent RNA polymerase, which, together with non-structural proteins 7 and 8, is responsible for the replication of the viral genome. There are still many questions about the underlying mechanisms of these key processes, and time-resolved cryo-EM studies will provide valuable information to advance our understanding of them. Here I present expression and purification protocols for S. aureus DNA gyrase subunits A and B and SARS-CoV-2 non-structural proteins 7, 8 and 12. DNA gyrase subunits A and B were expressed in Escherichia coli (E. coli) and purified in several steps, including affinity chromatography (His-Trap), ion exchange chromatography (IEX) and size exclusion chromatography (SEC). Despite many challenges with gyrase A precipitation, I obtained enough of both subunits for the intended cryo-EM. Different strategies to assemble them into a functional tetramer were tested but did not result in the expected outcome. The gained knowledge about the behaviour of the subunits in solution will serve as a basis for further optimization of the protocols before the assembly of the complex can be attempted again. Non-structural proteins 7 and 8 were expressed in E. coli as a polyprotein and successfully purified using His-Trap and SEC. I obtained a great amount of the polyprotein and established a protocol for its cleavage. Nsp12 was expressed using the baculovirus-insect cell expression system. The immunofluorescence assay data showed that the tested lipofection protocol works, and nsp12 is being produced in sufficient quantities. This result provides a solid base for further experiments to establish a purification method and assemble the nsp12-nsp7-nsp8 complex for cryo-EM imaging.
667

Expression of FLAG-tagged argonautes in Dictyostelium discoideum

Abdul Rahman, Zozek January 2022 (has links)
Argonautes are conserved RNA-binding proteins that can regulate gene expression post transcriptionally through a process known as RNA interference (RNAi). This is done through the use of small RNAs, e.g. sRNAs that act as a guide for the argonautes, allowing for sequence-specific binding to the target site. This interaction has been studied in many organisms, one of which is the model organism Dictyostelium discoideum. D. discoideum is an amoeba that has been used extensively in genetic experiments due to its unique lifestyle, and ease of use. Being a eukaryotic, unicellular organism, it proves to be a great tool for the study of regulatory systems in eukaryotes, allowing us to study this argonaute-sRNA interaction in detail. By analysing which RNAs bind to the argonautes, we can better understand which genes these proteins regulate and what role RNAi has in the organisms as a whole.  In this study, I investigate three of the five argonautes found in D. discoideum, namely agnA, agnC and agnE. By transforming FLAG-tagged versions of these genes into the amoeba, I successfully express two of these modified proteins in D. discoideum and verified expression by using antibodies designed specifically to recognise the FLAG-tags. This opens up the possibility for the characterisation of the argonaute proteins to better understand their role and function in the regulation of genes. / <p>The Biology Education Centre (IBG) is the responsible department. </p><p></p><p>Presentation has been made through Zoom. </p>
668

Flödescytometrisk undersökning av inbindning mellan designade topdomänen från transferrinreceptorn till virala glykoproteiner för potentiell användning inom läkemedelsframtagning / Flow cytometric investigation of binding between the designed top domain of the transferrin receptor to viral glycoproteins for potential use in drug development

Rydell, Emma January 2022 (has links)
Machupovirus är ett virus som kan orsaka hemorragisk feber hos människor. Efter utvärdering av bindning mellan designade proteiner och virala glykoproteiner skulle proteinerna potentiellt kunna användas vid framtagning av ett proteinbasserat läkemedel mot hemorragisk feber. Syftet med studien var att efter riktad evolution och framrening av optimerade varianter av proteinet AP01 undersöka inbindningen till virala glykoproteiner mellan designade AP01 proteiner och transferrinreceptorn med hjälp av flödescytometrisk undersökning. Den fysiologiska nivån av järn i kroppen upprätthålls av transferrin (Tf) och transferrinreceptorn (TfR), ett transmembranprotein bestående av tre domäner. TfR apikala domän används av glykoprotein 1 (MGP1) och Plasmodium vivax för att ta sig in i celler genom receptormedierad endocytos. Med rekombinant genteknik kan rekombinanta plasmider skapas där en gen av intresse ligeras in i en plasmid med hjälp av DNA-ligas. I studien skapades rekombinanta plasmider pET29b+/AP01 S2.1, S2.2, S2.3, S3.3, S3.4 och S3.6 som transformerades till E. coli. Erhållna resultat från sekvensering visade att samtliga sex AP01-gener hade ligerats i vektorn men sekvensering av rekombinanta plasmider visade att endast pET29b+/AP01 S2.1, S2.2, S2.3 och S3.6 hade nukleotidsekvens utan mutationer. Proteinuttryck inducerades innan proteiner renades fram med immobilized metal ion affinity chromatography (IMAC). Den uppskattade molekylvikten hos de framrenade proteinerna var 18 kDa som bestämdes med sodium dodecyl sulfate – polyacrylamid gel electrophoresis (SDS-PAGE) vilket överrenstämde med den teoretiska molekylvikten. Flödescytometri användes för att undersöka inbindningsförmågan mellan de uttryckta proteinerna och glykoprotein 1 (MGP1). Interaktionsbindningen mellan de designade proteinerna och MGP1 är bättre än interaktionen mellan originalgen AP01 och MGP1. De designade proteinerna visar på en svag effekt i den utförda ”competition assay” som gjorts vilket kan förklaras med en ej optimal struktur hos de designade proteinerna eller närvaro av BSA. / Machupovirus is a virus that can cause hemorragic fever in humans. After evaluating the binding between designed proteins and viral glycoproteins, the proteins could potentially be used in the development of a protein-based drug for hemorrhagic fever. The aim of the study was to investigate the binding to viral glycoproteins between designed AP01 proteins and the transferrin receptor after directed evolution and purification of optimized variants of the AP01 protein by means of flow cytometric examination. The physiological level of iron in the body is maintained by transferrin (Tf) and the transferrin receptor (TfR), a transmembrane protein consisting of three domains. The apical domain of TfR is used by glycoprotein 1 (MGP1) and Plasmodium vivax to enter cells through receptor mediated endocytosis. With recombinant DNA technology, recombinant plasmids can be created where a gene of interest is ligated into a plasmid using DNA ligase. In this study, recombinant plasmids pET29b+/AP01 S2.1, S2.2, S2.3, S3.3, S3.4 and S3.6 were created and transformed into E. coli. Sequencing results showed that all six AP01 genes had been ligated into the vector but sequencing of recombinant plasmids showed that only endast pET29b+/AP01 S2.1, S2.2, S2.3 and S3.6 had nucleotid sequence without mutations. Protein expression was induced before proteins were purified by immobilized metal ion affinity chromatography (IMAC). The estimated molecular weight of the purified proteins was 18 kDa as determined by sodium dodecyl sulfate – polyacrylamid gel electrophoresis (SDS-PAGE) which was consistent with the theoretical molecular weight. Flow cytometry was used to examine the binding ability between the expressed proteins and glycoprotein 1 (MGP1). The interaction binding between the designed proteins and MGP1 is better than the interaction between the original gene AP01 and MGP1. The designed proteins show a weak effect in the “competition assay” preformed, wich can be explained by a non-optimal structure how the designed proteins or the presence of BSA.
669

RNAlater som bevaringsmetod för muskelvävnad : En jämförande metodstudie om frystorkning, RNAlater och RNAlater-ICE som bevaring av skelettmuskulatur inför molekylärbiologiska analyser / RNAlater as a Method for Preservation of Muscle Tissue : A Comparative Method Study on Lyophilization, RNAlater and RNAlater ICE for Preservation of Human Skeletal Muscle Preceding Molecular Biological Analyzes

Engvall, Alice, Eriksson-Viklund, Tuva January 2022 (has links)
I denna metodstudie jämfördes Thermo Fishers bevarande lösningar RNAlater och RNAlater-ICE med frystorkning som bevaring av skelettmuskulatur från människa. Studien gjordes med syftet att avgöra om RNAlater och/eller RNAlater-ICE kan ersätta frystorkning, i hopp om att underlätta dissekering av muskelvävnad. De molekylärbiologiska analyser som utfördes var proteinbestämning; Western Blot inriktad på proteinerna mTor, S6, S6K1, eEF2, myosin typ II och aktin; samt mätning av glykogen och citratsyntasaktivitet. Därtill påbörjades även en aminosyraanalys. Studien utfördes hos William Apró på Åstrandlaboratoriet på Gymnastik- och idrottshögskolan i Stockholm. Resultaten visade att både RNAlater och RNAlater-ICE är olämpliga att använda i studier som innefattar samtliga av de genomförda analyserna. Detta då analysresultaten från de alternativa bevaringsmetoderna och de från frystorkningen inte var likvärdiga. Därmed drogs slutsatsen att varken RNAlater eller RNAlater-ICE kan ersätta frystorkning som bevaringsmetod i Aprós vidare studier. / In this method study Thermo Fisher’s preserving solutions RNAlater and RNAlater-ICE were compared to lyophilization for preservation of human skeletal muscle. The study was conducted with the aim of determining whether RNAlater and / or RNAlater-ICE can replace lyophilization, in the hope of facilitating dissection of muscle tissue. The molecular biological analyzes performed were protein assay; Western Blot focused on the proteins mTor, S6, S6K1, eEF2, myosin type II and actin; alongside of measurments on glycogen and citrate synthase activity. In addition, an amino acid analysis was initiated. The study was executed with William Apró at the Åstrand Laboratory at The Swedish School of Sport and Health Science in Stockholm. The results showed that both RNAlater and RNAlater-ICE are unsuitable for use in studies that include all of the analyzes performed. This is because the analysis results from the alternative preservation methods and those from lyophilization were not equivalent. Thus, it was concluded that neither RNAlater nor RNAlater-ICE can replace lyophilization as a preservation method in Apró’s further studies.
670

Validering av vankomycin-resistenta enterokocker : Diagnostik på panther fusion open access instrument / Validation of vancomycin-resistant enterococcus : Diagnostics on panther fusion open access instrument

Wared, Mary January 2022 (has links)
Panther Fusion® system är ett fullständigt automatiserat in vitro diagnostiksystem som har högt flöde av prov-till-resultat och tillåter utförandet av in vitro diagnostiska tester genom användning av realtids Polymerase Chain Reaction (realtids-PCR). Syftet med detta projekt är att validera om det finns möjlighet att använda ett kit från Amplidiag på Panther fusion open access för att diagnostisera vankomycin resistenta enterokocker (VRE) samt att utvärdera analys direkt på E-swab prover istället för anrikningsbuljong. Det är viktigt att kunna detektera vanA-och vanB-generna i prover för att VRE hyser dessa gener. Sensitivitet och effektivitet av Panther fusion open access undersöktes genom att analysera proverna parallellt med Bio-Rad CFX384/96-PCR som är rutinmetoden för VRE-diagnostik på Klinisk mikrobiologi i Lund. Specificitet av en tidigare publicerad PCR-mix (PCR-mix) som kan detektera vanA och vanB i prover jämfördes med Amplidiag assay mix 2 som används i rutinmetoden. För att kunna utvärdera skillnaden av specificiteten och känsligheten mellan E-swab och anrikningsbuljong utfördes analysen på både E-swab och anrikningsbulong med både Panther fusion open access och Bio-Rad CFX384/96-PCR. MgCl2- koncentration optimerades till 3,0 mM. Sensitivitet och effektivitet av Panther fusion open access var högre med PCR-mix än Amplidiag assay mix 2 och uppvisade optimalt linjäritet. Specificitetstest av PCR-mixen visade att den bara kunde detektera vanA och vanB. Resultaten av spikade VRE-negativa patientprover (E-swab) visade sig vara orimliga då flera av proverna och kontrollerna gav resultat för båda generna. För att ersätta VRE-diagnostik på Bio-Rad CFX384/96 med Panther fusion open access behöver ytterligare experiment genomföras direkt på E-swab och vankomycine variabla enterokocker (VVE)-prover på Panther fusion open access. / Panther Fusion® system is a fully automated in vitro diagnostic system that has a high flow of sample-to-results and allows the performance of in vitro diagnostics tests using real-time Polymerase Chain Reaction (real-time PCR). The purpose of this project is to validate whether it is possible to use a kit from Amplidiag on Panther fusion open access to diagnose vancomycin resistant enterococcus (VRE). In addition, this project aims to evaluate and analyze E-swab samples directly instead of enrichment broth. It is important to be able to detect VanA and VanB genes in samples because VRE harbors these genes. Sensitivity and efficiency of Panther fusion open access were tested by analyzing the samples simultaneously with Bio-Rad CFX384/96 which is the routine method for VRE diagnostic at Clinical Microbiology in Lund. Specificity of a previously published PCR-mix (PCR-mix) that can detect VanA and VanB genes in samples was compared with Amplidiag assay mix 2 used in the routine method. In order to evaluate the difference in specificity and sensitivity between E-swab and enrichment broth, the analysis was performed on both E-swab and enrichment broth with both Panther fusion open access and Bio-Rad CFX384/96-PCR. MgCl2 concentration was optimized to 3,0 mM. Both sensitivity and efficiency of Panther fusion open access were higher with PCR-mix than those with Amplidiag assay mix 2 and it showed optimal linearity. Specificity test of PCR-mix detected only VanA and VanB genes. The results of inoculated the negative VRE-patient samples (E-swab) indicated that they were unreasonable because some of the samples and controls gave results of both genes. Replacement of the VRE-diagnostic method on Bio-Rad CFX384/96 with Panther fusion open access requires performing additional experiments directly on E-swab and vancomycin variable enterococcus (VVE) samples using Panther fusion open access.

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