Detection of circulating tumor cells (CTC) in peripheral blood is indicative of early recognition of tumor progression and such an important biomarker for early diagnosis, staging, monitoring and prognosis of cancer. However, CTC are found in very low concentrations and reliable isolation of these rare cells is challenging. Microfluidics enables precise manipulation of fluids and cells and is ideal for cell sorting methods for clinical diagnostics. The thesis contributes towards the development of microfluidic based CTC isolation methods from peripheral blood. The methods are based on size and immunoaffinity. The first part of the thesis describes the phenomenon of inertial focusing for size based cell separation at high throughputs. In paper 1, we demonstrate continuous filtration of leukocytes from diluted blood, with an efficiency of 78% at a flow rate of 2.2ml/min. In the paper 2, separation of total and subpopulation of leukocytes with a purity of 86% for granulocytes and 91% for lymphocytes is demonstrated. Furthermore, cancer cells spiked into whole blood could be separated at a yield of 88%. Finally, in paper 3 and 4 we unravel parts of the unexplored elasto-inertial microfluidics and was utilized to precisely focus the cells, as part of an integrated optofluidic micro flow cytometer device, capable to simultaneously measure fluorescence and scattering of cells and particles at a rate of 2500 particles/sec (paper 4). Second part of the thesis focuses on acoustophoresis. In (paper 5), a multifunctional acoustic microdevice was developed for isolation of cancer cells from red blood cells with a separation efficiency of 92.4% and trapping efficiency of 93%. In (paper 6), microbubbles activated acoustic cell sorter was developed for affinity based cell separation. As a proof of principle, cancer cells in a suspension were separated at an efficiency of 75%. In the third part, using cellulose nano fibrils (paper 7), we demonstrate efficiently capture and release of cancer cells at a release efficiency of 95%. Finally, a novel, single step self-assembly of spider silk proteins is introduced inside microfluidic channels for effective capture of cancer cells with 85% capture efficiency and subsequent release of captured cells with 95% release efficiency (paper 8). The novel recombinant silk modified microfluidic device was validated using pancreatic cancer patients. In summary, we have developed different microfluidic based isolation technologies for the capture and characterization of CTC. / <p>QC 20170321</p>

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Denna rapport diskuterar vilka ämnen i urinen som påverkar förutsättningarna för utvecklingen av biofilm i Observe Medicals automatiska urinmätare Sippi och på så sätt stör mätsignalen. Idéer och förslag på åtgärder mot detta problem diskuteras. Rapporten tar upp fem olika lösningar som har testats med produkten: albumin utspätt med vatten, fritt hemoglobin utspätt med vatten, albumin blandat med urin, fritt hemoglobin blandat med urin samt endast urin. Volymmätningarna gick till på ett sådant sätt att varje lösning pumpades från en behållare till mätkammaren i Sippins engångsset. Alla mätningar utfördes med två varianter av engångsset. I den ena varianten fanns det en silikonolje-kapsel placerad i mätkammaren och i den andra saknades kapseln. Laborationsresultaten visade att albumin ger upphov till fullständig biofilmsutveckling redan efter ett fåtal timmar. Fritt hemoglobin har medfört varierande grad av biofilmsutveckling, beroende på koncentrationen blod i lösningen. Silikonolje-kapseln motverkar effekten av albumin i större grad än fritt hemoglobin. Urin med lågt pH (6,0) visade sig inte ge upphov till biofilm i lika stor utsträckning som urin med högre pH (7,0). Rapporten diskuterar kring det faktum att lågt pH i urinen har en negativ påverkan på förutsättningarna för biofilm, och därmed eventuellt kan användas för att utveckla produkten i framtiden. Rapportens slutsats blev att både albumin och fritt hemoglobin bidrar till utvecklingen av biofilm i Sippi och därmed påverkar mätsignalen. / The following report discusses what substances affect the conditions for the formation of biofim in Observe Medicals digital urine measurement system Sippi, and therefore interfere with the measuring signal. Suggestions on how to possibly avoid volume measurement errors are given. The report accounts for five different solutions used during laboratory experiments: albumin mixed with water, free hemoglobin mixed with water, albumin mixed with urine, free hemoglobin mixed with urine, and lastly only urine. During the volume measurements, fluid was pumped from a container to the measurement chamber in the Sippi set. Each measurement was performed twice, with and without a silicon capsule in the chamber. The laboration results showed that albumin develop a complete biofilm after a few hours. Free hemoglobin entailed a varying degree of biofilm development in Sippi, depending on the amount of blood in the solution. The silicon capsule counteracts the effect of albumin to a higher degree than free hemoglobin. Furthermore, urine with low pH (6,0) did not give rise to biofilm to the same extent as urine with high pH (7,0). The report discusses about the fact that low value of pH in urine negatively affects the conditions for formation of biofilm, and may be used to further develop the product in the future. The report concludes that both albumin and free hemoglobin contribute to construction of biofilm in Sippi, and therefore interfere with the signal.

För att kunna bedriva forskning i det nybyggda rummet på Karolinska Universitetssjukhuset vid Rosenlunds Sjukhus krävs det att magnetfäl- tet valideras. Detta är av vikt att undersöka för att kontrollera om det finns möjlighet att installera en teleslinga, samt säkerställa att mag- netfältet som genereras från högtalarna inte blir för stort för framtida forskning på bland annat hörapparater med telespole. Magnetfältsnivån mättes i tomt rum och med inkopplade högtalare som genererade ett monotont ljud motsvarande talstyrkan hos en vux- en man. Bakgrundsmagnetfältet var i det stora hela inom gränsvärdena givna av IEC 60118-4 bortsett från ett fåtal mätpunkter. Vid högtalarmät- ningarna visade det sig däremot att flertalet mätpunkter intill högta- larna inte höll sig inom gränsvärdena. Magnetfältet, som genererades av strömmen till högtalarna, avtog snabbt med avståndet. Detta med- för att högtalarnas placering är av betydelse och att det bör tas hänsyn till. / To perform research in a new room at Karolinska University Hospital, Rosenlund Hospital, it has to be validated regarding to magnetic field. This is of importance to verify if it is possible to install a hearing loop, as well to make sure that the magnetic field generated from the speak- ers does not cause problems at future research regarding for example hearing aids with a telecoil. The magnetic field level was measured in the room when it was empty and with connected speakers generating a monotonous sound corre- sponding the speech level from a grown man. The background magnetic field level was mainly within the limits given by IEC 60118-4 aside from a few measuring points. The measurements with speakers connected showed that several measuring points close to the speakers were not within the limits. Although the magnetic field, generated by the current to the speakers, decreased rapidly with dis- tance. The placement of the speakers are therefore significant and have to be accounted for.

Vid diagnostisering av hjärtsjukdomar används ofta ekokardiografi för kartläggning av hjärtats storlek, funktion och blodflöde. Dessa undersökningar utförs dagligen på Fysiologkliniken vid Karolinska Universitetssjukhuset. Idag sker inmatning av undersökningsvärdena manuellt och sparas i pappersarkiv. Målet med detta projekt var att skapa en databas som tar hand om dessa värden och effektiviserar det dagliga arbetet. Detta projekt är en fortsättning på ett tidigare projekt från 2012, vilket inte kunde avslutas i tid. Databasen har skapats i databasprogrammet FileMaker och har till stor del utformats efter en modifierad version av den kravspecifikation som sattes upp i det tidigare projektet. Projektet resulterade i en databas som för närvarande går under namnet CardioEchoBase (CEB) vilken uppfyller alla de krav som ställdes förutom automatisk importering av värden från ultraljudsmaskiner. / When diagnosing heart diseases echocardiography is often used for identification of cardiac size, function and blood flow. These examinations are carried out daily at the Department of Clinical Physiology at Karolinska University Hospital. Today, entry of examination values is done manually and stored in paper files. The goal of this project was to create a database that takes care of these values and streamlines their daily work. This project is a continuation of a prior project from 2012, which could not be completed in time. The database has been created in the database software FileMaker and has mainly been designed after a revised version of the specification of requirements set in the previous project. The project resulted in a database that currently goes by the name CardioEchoBase (CEB) which meets all the requirements that was set besides automatic import of data from ultrasound machines.

Barn med en allvarlig cerebral pares (CP) diagnos har begränsad eller obefintlig förmåga att stå självständigt. Tillståndet medför även en stor risk för subluxation i höftlederna. En befintlig teori bland ortopeder och sjukgymnaster idag är att hjälpmedel för ståträning för barn med CP, såsom ståskal, med höfter i ett abducerade läge kan motverka höftledernas negativa utveckling. Hittills saknas det dock vetenskapliga bevis för denna teori. TeamOlmed Barn &amp; Ungdom tillverkar ståskal med 30 graders abduktionsvinkel enligt teorin ovan. Men kunskaperna inom området är begränsade och företaget önskade undersöka om hypotesen stämmer och hur de biomekaniska förutsättningarna påverkas av ståskalen. Detta examensarbete fokuserar på olika ståställningar i abduktion för en frisk person och dess inverkan i de nedre extremiteterna i syfte att undersöka den befintliga teorin. Rörelseanalyssystemet Vicon Nexus användes för datainsamling och analys av moment kring knälederna. Vid analys av krafterna i höftlederna användes OpenSim, ett simuleringsprogram för det muskuloskeletala systemet i 3D. Resultatet från Vicon visar att knäna har ett inre varusmoment i frontalplanet, vilket är ofarligt för knälederna, i såväl abducerade som vanlig höftposition. Simuleringsresultatet från OpenSim visar att kraftvektorernas riktningar ändras i samband med ändringar av abduktionsvinklar. Detta betyder att kraftvektorernas riktningar i höfterna, uttryckta i femurs koordinatsystem, är snarlika för ståpositioner med olika abduktionsvinklar. Beloppet av kontaktkraften ökade dock med ökande höftabduktionsvinkel. Momenten som uppstår vid olika ståställningar är ofarliga för knälederna och kraftvektorernas riktningar i höfterna är oberoende av abduktionsvinklarna för en frisk person. Den enda skillnaden i höftbelastning med stående i höftabduktion var ökade belopp av höftkontaktkrafter. För att noggrannt kunna utvärdera huruvida en ökad kontaktkraft kan påverka höftens tendens att migrera ur led, samt huruvida liknande observationer finns hos patienter med CP skador i sina ståskal, krävs det vidare studier. Tack vare observationerna av denna pilotstudie kan man ställa mer relevanta studiefrågor kring biomekaniska mekanismer i en större studie med barn med CP-diagnoser.

Several studies suggest that the use of ultrasound in conjunction with microbubbles (MBs) can induce the lysis of the blood clots through acoustic cavitation and through the production of microjets and microstreaming. However, there is no accordance about the optimal ultrasound parameters that have to be considered in order to achieve the maximum thrombolytic effect, neither a clear agreement about the type of MBs that have to be used. This project had two main goals: the design and optimization of an in-vitro set-up for the study of clot lysis within coronary arteries and its testing with ultrasound in conjunction with two different types of MBs. The MBs considered were the 3MiCRON MBs and the SonoVue MBs. The ultrasound sequence was developed using a programmable ultrasound architecture (Verasonics, Inc) and was tested using commercially available clinical transducers. Using the designed set-up and varying the ultrasound parameters (frequency, pulse length and pulse amplitude) it was possible to study the clot lysis effciency in conjunction with the two types of MBs. For the 3MiCRON MBs no increase in clot lysis was found with the implemented ultrasound parameters, while considering the SonoVue MBs, a 10% increase in clot lysis was found with 10ms long pulse delivered at 50V (peak-to peak value). The obtained set-up had several aspects in common with the real situation of occluded coronary arteries, although some limitations were present and further optimizations are required. Further work is required in order to assess if different combination of ultrasound parameters are able to lead to an increase in clot lysis when delivered with 3MiCRON or SonoVue MBs.

Human skin has various pathologies in the form of acute and chronic diseases. Some are only cosmetic diseases which are not harmful for life but they can affect mental health and disrupt daily activities. Hyperhidrosis is one of these cosmetic diseases which may be caused by diabetes, infections, or thyroid hyper activity, or can be inherited. There are some examinations for testing hyperhidrosis, e.g. gravimetric and minor starch-iodine test. There are some devices that can measure sweat but are not specifically used or even intended for use on hyperhidrosis. A non-invasive prototype instrument called Electronic Sudometer using the principle of electrical impedance measurement has been developed. The philosophy behind this prototype is to make an instrument which can detect hyperhidrosis during homeostasis as well as in pathological condition. The device injects a sinusoid electric current and detects the ensuing voltage, which is proportional to the impedance of sweat on top of the skin during hyperhidrosis. For this prototype, the electrode system is made of brass rings mounted on a handle. The signal is then processed in electronic assembly. Processed output is transferred to a Laptop with specially made connecting wire. Computer having Sound Card Oscilloscope (Lab View based software) plots the signal and shows voltage level corresponding to sudor level. The signal output can also be displayed on a SmartPhone having software called Osciprime, requiring another specially made interface. Laboratory test results in the form of a plot of output voltage vs. impedance show accuracy of the device. The impedance results can be translated to sweat level because impedance decreases with increasing sweat during hyperhidrosis. The Sudometer was also calibrated using fixed precision resistors over its working range. Laboratory tests were carried out using an artificial skin at various sweat levels and to a yeast tissue model. Hydration of the artificial skin was quantified by weighing precision cut samples on a laboratory balance. Results from two test persons (the author and a student friend) are also included in this Master Thesis. During these experiments, the laptop computer and SmartPhone, respectively, were on internal battery to eliminate electric hazard. Any clinical device must be validated for accuracy and evaluated for safety before applying it on patients – the latter has not been done with the prototype. The author is aware of potential electrical risks, and thus the whole system was disconnected from mains 230V during measurements on himself and a student friend. The device output seems to be well correlated to sweat level although electrolytes were not taken into account. Being a palmar hyperhidrosis patient himself, the author applied the Electronic Sudometer on his palms and the results look quite promising. At different environmental temperatures, the author checked elicited sweat responses. Patient safety is always a concern for clinicians regarding new devices. For this reason, the device itself has been made battery operated, and a new version will be entirely powered from a SmartPhone.

A solution to distinguish ventricular fibrillation and ventricular flutter from other arrhythmias and from disturbances caused by body motion or muscle activity with the use of a neural network has been investigated. Ventricular fibrillation and ventricular flutter occurs when the cardiac muscle cells are not triggered by the cardiac conduction system, but rather by ectopic foci preventing a synchronized contraction of the cardiac muscle cells and therefore inhibiting the hearts capability to properly pump blood. Two different methods, gradient descent and quasi-Newton, used by the network for learning was tested and preprocessing methods used on the input data before introducing it to the network was evaluated. Gradient descent makes use of the gradient to the error function with regards to its weights and updates the network in the direction which the output error by the network decreases the most. Quasi-Newton update the network roughly in the Newton direction by iteratively build up an approximation to the Hessian of the error function with the use of information from the gradient. The preprocessing methods used were: Threshold Crossing Intervals (TCI) which looks at the time between baseline crossings of the ECG signal. Mean Absolute Value (MAV) which computes the mean absolute value of the normalized ECG signal. Spectral Analysis which takes into account different properties of the frequency spectrum of ventricular fibrillation and normal sinus rhythm. VF-filter which assumes VF to be sinusoidal and computes the leakage after the ECG signal has been bandstop filtered around the mean frequency. Period and Amplitude Information of the maximum amplitude of the input frequency spectrum and its period. It was found that the networks that used the preprocessed signal was a poor classifier for the arrhythmias partially because ventricular fibrillation was not easily separable from the arrhythmias by the implementaion of the preprocessed inputs given.

Epilepsy is a neurological disorder affecting 1-2 % of the population in the world. People diagnosed with epilepsy are put at high risk of getting injured due to the unpredictable seizures caused by the disorder. Electroencephalography (EEG) in combination with machine learning can be used for prediction of an epileptic seizure. Therefore, a portable prediction device is of great interest with high emphasis for it to be user-friendly. One way to achieve this is by minimizing the number of electrodes placed on the scalp. This study examines the number of electrodes that provide sufficient information for prediction of a seizure. The highest prediction accuracy of 91 %, 97 % sensitivity and 85 % specificity was achieved with as few as 16 electrodes. Due to the limitation of the intracranial EEG recordings further testing must be performed on scalp EEG recordings to provide valid results.