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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.
321

Analysis and validation of Interferon Regulatory Factor 5 (IRF5) on circulating microparticles in patients with SLE

Singthongthat, Wanwisa January 2020 (has links)
Introduction: Systemic lupus erythematosus (SLE) is an autoimmune disease that cause various inflammatory conditions in the body. The pathogenesis of this disease is yet unknown, and the diversity within the patients bring on major obstacle to clinical research for specific diagnostic markers. As a biomarker of SLE, both Interferon Regulatory Factor-5 (IRF5) and Microparticles (MP) have been suggested. Recently a study demonstrated higher concentration of IRF5+ MP in a small number of SLE patients compared to controls.  Aim: The purpose of this study was to validate and analyze IRF5+ MPs in a larger number of SLE patients and compare the results to known SLE subgroup based on IRF5 concentration.  Materials and methods: Totally 50 plasma samples from a larger cohort of SLE-patients (n=35) was analyzed together with population-based controls(n=15). Three different antibodies (in-house and commercial) were used for detection of IRF5+ MP with flow cytometry. Students t-test was used to investigate significant differences between SLE subgroup, controls and compared to the previous values. Results and Conclusion: The concentration of IRF5+ MP in SLE subgroup was significantly higher compared to controls (p<0,05). However, there were no correlations between our results and the values from the previous study, suggesting that both methods measure various forms of IRF5. These results imply that IRF5+ MP could be a possible biomarker for pathogenesis in SLE, but further studies are needed for a better understanding of IRF5, as well as of MP.
322

DEVELOPING A MOLECULAR TOOL KIT FOR DIAGNOSTIC PCR

Mohamed Moumin, Neima January 2019 (has links)
ABSTRACT The aim of this study is develop and test an inexpensive molecular tool kit to be used for diagnostic PCR for diseases such as Leber hereditary optic neuropathy (LHON) and Cystic fibrosis(CF). By developing and optimizing recombinant Taq polymerase and making a DNA size ladder from plasmids pPSU1 and pPSU2 the financial cost for the tool kit would be reduced significantly compared to the commercial components. With an inhouse method both the recombinant Taq polymerase and the pPSU1 and pPSU2 plasmids were purified from the E.coil strain DH5-α. Thereafter to analyse the components of the tool kit both conventional PCR and Real-time PCR to make sure that the tool kit would work for both types of PCRs.     The homemade Taq polymerase proved to be able to sustain in room temperature for at least 24 h and the polymerase also showed that it works with different primers such as LHON, CF and Beta-globin in both endpoint and probe base real-time PCR. The homemade size marker produced a reliable in agarose gel electrophoresis but requires optimization for continued usage for smaller PCR products.     In conclusion the homemade Taq polymerase will be used in future PCR analysis in the laboratory and the recombinant production process as well. Meanwhile the homemade size marker did not work sufficiency enough to be continuously used with gel electrophoresis in the laboratory without being further modified.
323

Presence of Popliteal Artery Entrapment Syndrome in asymptomatic individuals during ultrasound examinations with plantar flexion

Wakter, Jacob January 2021 (has links)
Popliteal artery entrapment syndrome has been reported to be a rare disease typically found in athletic and otherwise healthy young adults. It manifests as a temporary lower limb pain that occurs in connection with physical exercise. It is caused by an anatomic anomaly, usually anaberrant head of the gastrocnemius muscle that compresses the popliteal artery on the backside of the knee joint. The popliteal artery is the main vessel supplying blood to the lower part of the leg and the condition, if left untreated, can lead to serious complications such as thrombosis or aneurysm. If detected in time and surgically corrected patients can expect full recovery within weeks.The purpose of this study was to examine a group of healthy asymptomatic individuals (n=50)using ultrasound and a series of provocation to see if there was a possibility of entrapment. A secondary objective was to find which maneuvers during the ultrasound would provide the best results. They were subjected to ultrasound examinations at rest, during plantar flexion without resistance, against a light resistance and against substantial resistance.The results showed that most of the test subjects could temporarily constrict blood flow greatly although ultrasound imagery alone was not enough to confirm diagnosis. It seems that detected occlusion of the artery in conjunction with other diagnostic data such as AnkleBrachial Index and symptomatology can be useful both in confirming or ruling out PAESwithout the use of more expensive and invasive methods.
324

Processing of the Phonocardiographic Signal : methods for the intelligent stethoscope

Ahlström, Christer January 2006 (has links)
Phonocardiographic signals contain bioacoustic information reflecting the operation of the heart. Normally there are two heart sounds, and additional sounds indicate disease. If a third heart sound is present it could be a sign of heart failure whereas a murmur indicates defective valves or an orifice in the septal wall. The primary aim of this thesis is to use signal processing tools to improve the diagnostic value of this information. More specifically, three different methods have been developed: • A nonlinear change detection method has been applied to automatically detect heart sounds. The first and the second heart sounds can be found using recurrence times of the first kind while the third heart sound can be found using recurrence times of the second kind. Most third heart sound occurrences were detected (98 %), but the amount of false extra detections was rather high (7 % of the heart cycles). • Heart sounds obscure the interpretation of lung sounds. A new method based on nonlinear prediction has been developed to remove this undesired disturbance. High similarity was obtained when comparing actual lung sounds with lung sounds after removal of heart sounds. • Analysis methods such as Shannon energy, wavelets and recurrence quantification analysis were used to extract information from the phonocardiographic signal. The most prominent features, determined by a feature selection method, were used to create a new feature set for heart murmur classification. The classification result was 86 % when separating patients with aortic stenosis, mitral insufficiency and physiological murmurs. The derived methods give reasonable results, and they all provide a step forward in the quest for an intelligent stethoscope, a universal phonocardiography tool able to enhance auscultation by improving sound quality, emphasizing abnormal events in the heart cycle and distinguishing different heart murmurs.
325

Preanalytiska faktorer och dess påverkan på levermarkörerna ALAT, ASAT och bilirubin : En allmän litteraturstudie / Preanalytical factors and their effect on the liver markers ALAT, ASAT and bilirubin : A literature review

Erlandsson, Kristin, Klasson, Evelina January 2020 (has links)
Preanalytiska faktorer såsom provhantering och förvaring utgör den vanligaste felkällan inom laboratoriemedicin, vilket tyder på bristande kunskap kring faktorer som påverkar provers stabilitet. ALAT, ASAT och bilirubin är markörer för utvärdering och behandling inom leverdiagnostik, varpå tillförlitliga provsvar är av stor vikt.Syfte: Att granska tidigare studier och göra en sammanställning av stabiliteten för ALAT, ASAT och bilirubin vid olika typer av förvaring innan och efter centrifugering, olika centrifuginställningar, samt i rör med olika tillsatser.Metod: En allmän litteraturstudie gjordes genom systematisk sökning och bearbetning av vetenskapliga artiklar relaterade till syftet.Resultat: Studierna om analytstabilitet hos centrifugerade prover hade en stor spridning mellan resultaten som kan förklaras av studiernas olika upplägg, främst med tanke på att de pågick under olika lång tid. Gällande jämförelse av provrör skiljde det som mest fem dagar mellan PST och Barricor-rör i en av studierna. Studierna om centrifugering visade inte på någon skillnad i stabilitet med de inställningar av centrifugalkraft och tid som användes.Slutsats: Bristen på studier med liknande studiedesign gör det svårt att dra några säkra slutsatser kring stabiliteten vid olika förvaring. Resultatet antyder att varken olika rörtillsatser, centrifuginställningar eller fördröjd centrifugering upp till 24 timmar påverkar stabiliteten för ALAT, ASAT eller bilirubin. / Preanalytical factors such as specimen handling are the most common source of error in laboratory medicine, suggesting a lack of knowledge about factors affecting sample stability. ALAT, ASAT and bilirubin are markers that underlie evaluation and treatment in liver diagnostics, therefore reliable test answers are of great importance.Objective: To review previous studies and compile the stability of ALAT, ASAT and bilirubin for different storage before and after centrifugation, different centrifuge settings, and in tubes with different additives.Method: A literature review was done through systematic search and processing of scientific articles related to the objective.Results: The studies on analyte stability of centrifuged samples showed great variance between the results, mainly due to the studies lasting for different lengths of time. One study comparing test tubes showed a five day difference for ASAT between PST and Barricor tubes. Centrifugation studies showed no difference in stability with the centrifugal settings used.Conclusion: The lack of studies with similar study designs makes it difficult to draw any certain conclusions about the stability in different storage conditions. The result suggests that neither different tube additives, centrifuge settings nor delayed centrifugation up to 24 hours affect the stability of ALAT, ASAT or bilirubin.
326

Hudtemperaturens inverkan på sensorisk nervledningshastighet i nervus medianus / Impact of skin temperature on sensory nerve conductivity in the median nerve

Nigussie, Mehalet, Sabrin, Thwainy January 2020 (has links)
Kännedom om effekten av temperaturvariationer på det perifera nervsystemet ger en djupare förståelse för de fysiologiska mekanismerna som ligger till grund för funktionen av neuromuskulär påverka vid patologiskt och friskt tillstånd. Syftet med den här studien är att redogöra för hur den sensoriska nervledningshastigheten, distal latens och amplitud en i nervus medianus påverkas vid temperaturförändringar på handryggen från 26 till 33 °C. Studien omfattade 19 deltagare mellan 20–40 år. Mätningarna utfördes vid tre temperaturintervaller; kall (26–27° C), ljummen (28–29° C) och varm (32–33° C) för varje deltagare.   I denna studie observerades sensorisk nervledningshastigheten och distal latens visade ett signifikant samband med p-värde<0.001. Temperaturökningen leder till ökad nervledningshastighet med 1,61 m/s/° C och distal latensen reduceras med 0,1 ms/° C. Däremot sågs inget samband mellan amplitud med p-värde=0.87 och temperaturökningen. Temperaturförändringen har en påverkan på perifera nerver, detta bör uppmärksammas vid elektroneurografisk undersökning.  Det är viktig att uppnå den standardtemperaturen (31–34°C) vid en elektroneurografisk undersökning för att ställa rätt diagnos. Vid svårigheter med att upp nå den standardtemperaturen kan en korrektionsfaktor användas. / Understanding the effect of temperature on the peripheral nervous system helps to have a better knowledge of the physiological mechanisms and functionality of the neuromuscular system. This study aimed to analyze the effect of temperature change, from 26 to 33°C at the dorsal side of the hand, on the sensory conduction velocity, distal latency, and amplitude of the median nerve. The study consists of 19 individuals between 20–40 years. The measurement was carried out at three temperature ranges: cold (26–27°C), intermediate (28–29°C), and warm (32–33°C).   Sensory conduction velocity and distal latency were significantly correlated to temperature with a p-value <0.001.  Sensory nerve conduction velocity and distal latency changes by 1,61 m/s and 0.1 ms with a temperature change of 1°C, respectively. In this study, the author did not observe a significant correlation (p-value of 0.82) between temperature and amplitude due to the large variability of amplitude in the temperature range used in this study. It is important to perform electroneurographic diagnosis at a temperature of over 31-34°C, otherwise, a correction factor must be used for a reliable diagnosis.
327

Visual Evoked Potentials : Referensvärden och könsskillnader / Visual Evoked Potentials: Reference Values and Gender Differences

Bergkvist, Linn January 2020 (has links)
No description available.
328

Hur kan injicerad aktivitet individanpassas vid skelettscintigrafi? Effekten av patientspecifika parametrar / How can injected radiation dose be adjusted for bone scintigraphy? The effect of patient-specific parameters

Chermiti, Amro January 2020 (has links)
Bakgrund: Skelettscintigrafi är en nuklearmedicinsk undersökning. Undersökningen är den mest använda nukleardiagnostiska metoden och den genomförs ofta som en helkroppsundersökning. För att undersökningen ska kunna erhålla sin diagnostiska kvalitet, samt följa strålsäkerhetsmyndighetens rekommendationer behövs det mer kännedom till hur optimeringen ska följa as low as reasonably achievable (ALARA). Studiens syfte var att optimera patientstråldos samt att undersöka hur injicerad aktivitet kan anpassas efter patientens specifika parametrar. Metod: Studiegruppen bestod av 85 patienter som genomgick skelettscintigrafier vid Central sjukhuset i Karlstad, från perioden februari-april 2020. Resultat: Visade att både ålder och vikt är patientspecifika variabler som borde tas till betraktning vid bestämning av injicerad strålningsdos. Konklusionen: För att optimera undersökningen för varje patient bör injicerad aktivitet anpassas efter både kroppsvikt och ålder. Fler studier där andra parametrar undersöks måste genomföras. / Background: Bone scintigraphy is a nuclear medicine procedure. It is the most used nuclear diagnostic method and provides the opportunity to perform a full-body examination. For the method to retain its diagnostic quality, and to follow the recommendations of the Radiation Safety Authority, more knowledge is required on how the optimization should follow as low as reasonably achievable (ALARA). The purpose of the study was to optimize patient radiation dose and to investigate how the injected activity can be adapted to patient-specific parameters. Method: The study group consisted of 85 patients who underwent bone scintigraphy at the Central Hospital in Karlstad, from the period February-April 2020. Result: Showed that age and weight are patient-specific variables that should be considered when determining injected radiation dose. Conclusion: To optimize the examination for each patient, injected activity should be adjusted according to the patient’s body weight and age. More studies in where other parameters are investigated must be carried out.
329

Signifikanta skillnader i spirometrivariabler observerad mellan en Jaeger MasterScreen och en Vyntus spirometer : En jämförelse studie mellan två olika lungfunktionsutrustningar / Significant differences in spirometry variables observed between a Jaeger MasterScreen and a Vyntus Spirometer : A comparison study between two different lung function equipments

Zilic, Ada January 2020 (has links)
Introduktion: En av de vanligaste undersökningsmetoderna för att bedöma den respiratoriska funktionen är spirometri. Det är en undersökning som mäter lungvolymer och lungvolymsförändringar över tid. En fullständig lungfunktionsundersökning består av statisk och dynamisk spirometri samt mätning av diffusionskapacitet. Studiens syfte var att jämföra två olika utrustningar, en gammal (Jaeger MasterScreen Body och PFT) och en ny utrustning (Vyntus Body och One) om det fanns någon signifikant skillnad på mätresultatet mellan utrustningarna. Metod och material: Studien bestod av 24 testpersoner, 16 kvinnor och 8 män, alla undersökningar utfördes på Fysiologiska kliniken på Västerås sjukhus under februari och april 2020. Variablerna som undersöktes och bearbetades var vitalkapacitet (VK), forcerad vitalkapacitet (FVK), forcerad exspiratorisk volym på en sekund (FEV1), forcerad exspiratorisk volym uttryck i procent med vitalkapacitet (FEV%VK), total lungkapacitet (TLK), residualvolym (RV), mätning av diffusionskapacitet (DLCO) samt alveolär ventilation (VA). Resultat: Resultatet från studien visade att det förelåg en statistisk signifikant skillnad mellan utrustningarna Jaeger och Vyntus. Lungfunktionsutrustningen Vyntus påvisade ett lägre mätresultat på samtliga variabler. Att det förelåg en statistisk signifikant skillnad kan bero på att utrustningarna använder olika mätmetoder, Jaeger har en pneumotach medan Vyntus har en ultraljudssensor. Slutsats: Slutsatsen är att det föreligger systematisk skillnad på den nya utrustningen Vyntus. Vyntus visade lägre värden på samtliga variabler. / Introduction: One of the most common measurements for assessment of pulmonary function is spirometry. It is a method that measures lung volumes and changes in lung volume over time. A complete lung function test consists of static and dynamic spirometry as well as measurement of diffusion capacity. The purpose of the study was to compare two different equipment, an older (Jaeger MasterScreen Body and PFT) and the contemporary (Vyntus Body and One) if there was any significant difference in the measurement result between the two equipment. Method and materials: The study consisted of 24 test subjects, 16 women and 8 men, all examinations were performed at the Physiological Clinic at Västerås Hospital between February and April 2020. The variables investigated and processed were vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory volume expression as a percentage with vital capacity (FEV%VC), total lung capacity (TLC), residual volume (RV), diffusion capacity measurement (DLCO) and alveolar ventilation (VA). Result: The results of the study showed that there was a statistical significant difference between the two equipments Jaeger and Vyntus. The lung function equipment Vyntus showed a lower measurement result on all variables. This statistical significant difference may be due to the fact that the equipment uses different measurement methods. Jaeger has a pneumotach while Vyntus has an ultrasonic sensor. Conclusion: The conclusion is that there is a systematic difference in the new Vyntus equipment. Vyntus showed lower values for all variables.
330

En jämförelsestudie mellan manuell, semiautomatisk och automatisk utlinjering av endokardiet vid bedömning av ejektionsfraktionen. / A comparative study between manual, s semiautomatic and automatic tracing of the endocardium the assessment of ejection fraction.

Petersson, Ida January 2020 (has links)
Introduktion: Vid ekokardiografi används ultraljudsvågor med frekvens över 20 000Hz. Ultraljudssändare med piezoelektriska kristaller används för att generera ljudvågor som skickas ut i kroppen, reflekteras och sedan återvänder till kristallerna för att skapa en ultraljudsbild. Ejektionsfraktionen uttrycker hur stor del av den diastoliska volymen som pumpas ut i kroppen under systole och är en viktig parameter vid bedömning av den globala systoliska funktionen. Den rekommenderade metoden Simpsons biplan jämförs med Philips automatiska funktion a2Dq, som utgår ifrån speckle tracking principen, för bedömning av ejektionsfraktionen. Material och metod: 32 hjärtfriska testpersoner mellan 20–43 år inkluderades i tvärsnittsstudien. Apikala 4- och 2-kammarbilder insamlades ifrån testpersonerna och användes för beräkning av ejektionsfraktionen. Den manuella metoden Simpsons biplan grundas på operatörens utlinjering av endokardiet. Den automatiska funktionen a2Dq utgår ifrån 53 hjärtmodeller och placerar en region of interest automatiskt. Den semiautomatiska funktionen används genom att operatören modifierar region of interest men inte längden av vänsterkammaren. Resultat: Resultatet visade att det inte förelåg någon signifikant skillnad i mätvärdena av ejektionsfraktionen mellan de tre mätprinciperna. Den semiautomatiska och manuella metoden som är operatörsberoende hade likvärdiga mätresultat. Den automatiska funktionen erhöll totalt 6 mätvärden som hamnade utanför normalgränserna. Diskussion: Automatiska funktioner för bedömning av ejektionsfraktionen utvecklas snabbt och kräver utvärderingar. Automatiska mätningar har påvisats vara fördelaktiga då de inte är så tidskrävande som den manuella Simsons biplanmetoden. Tidsaspekten framhävs i de flesta studier dock på bekostnad av säkra mätresultat. Observationerna i denna studie påvisar att den automatiska funktionen inte är säker nog för användning. Konklusion: Enligt observationer ifrån denna studien rekommenderas att den automatiska funktionen ifrån Philips inte används. / Introduction: Ultrasound are soundwaves with frequencies above 20 000Hz. Piezoelectric crystals are used to generate sound waves that can be transmitted into the tissue and reflected back to the crystals to obtain an ultrasound image. The ejection fraction expresses how much blood the left ventricle pumps out with each contraction and is an important parameter for assessment of the hearts global systolic function. The recommended method Simpson´s biplane to assess ejection fraction is compared with Philips automatic function a2Dq, which is based on the principle of speckle tracking. Material and method: The study population included 32 tests subjects with age between 20-43 years old. The test subjects had no records of earlier heart pathologies. Apical 4- and 2-chamber images were collected for the purpose to measure the ejection fraction. The manual method Simpson´s biplane is based on the sonographers manual tracking of the endocardial border. The automatic function a2Dq is based on 53 heart models with different anatomy and physiology and applies a region of interest automatically along the endocardial border. The semi-automatic function allows the sonographer to adjust the region of interest but not the length of the chamber. Result: The result showed that there was no significant difference in the measured values of ejection fraction between the three different techniques. The semi-automatic and Simpson´s biplane method showed equivalent results. The automatic function showed a wide variance of measurements which resulted with a total of 6 measurement ended up below the normal values for ejection fraction. Discussion: Automatic functions for assessing the ejection fraction rapidly develops and requires validations. Automatic functions have shown to be advantageous as the are not as time-consuming as the manual Simpson´s biplane method. In most studies, however, the time aspect is emphasized at the expense of correct measurements results. The observations in this study show that the automatically function a2Dq from Philips are not providing correct measurements. Conclusion: According to observations in this study, it´s recommended that the automatic function from Philips shouldn’t be used.

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