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  • 1.
    Abbas, Hassan
    et al.
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Huzeirovic, Melisa
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    En jämförelse mellan två sjukdomsgrupper med PET/CT som undersökningsmetod: Beräkning av den totala effektiva dosen från PET- och CT-undersökning2019Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    Background: Lung cancer and malignant melanoma are diseases investigated by the dual-modality positron emission tomography/computed tomography (PET/CT). There are radiation risks with the examination that can appear as stochastic effects such as cancer. The aim of this study was to compare the radiation doses between the lung cancer group (suspected or verified) and the malignant melanoma group by calculating the total effective radiation dose and to declare the risk with the PET/CT examination. Material and method: The material contained parameters regarding the examination and the sample contained 20 patients from the two groups. The method was retrospective with a quantitative approach. Results: There was a significant difference (p <0,001) between these two groups, were the lung cancer group received 11,95 milliSievert (mSv) and the malignant melanoma group 6,03 mSv and the percentage risk for lethal cancer increased by 0,06% and 0,03%, respectively. Conclusions: The lung cancer group received twice as much effective dose than the malignant melanoma group. However, the effective dose is so low that the risk increase of the lethal cancer is marginal, and the benefit of the examination outweighs the risks.

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  • 2.
    Abbas, Monika
    Örebro University, School of Health and Medical Sciences.
    Bedömning av variabler vid postocklusiv reaktiv hyperemi (PORH)-test med Laser Doppler Flowmetry teknik2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 3.
    Abdallah Athumani, Ngenya
    Örebro University, School of Health Sciences.
    Characterization of tick-born encephalitis and West Nile virus non-structural 5 protein interactions with host factors involved in immune evasion and cellular apoptosis.2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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    Characterization of tick-born encephalitis and West Nile virus non-structural 5 protein interactions with host factors involved in immune evasion and cellular apoptosis.
  • 4. Abdelfatah Possnert, Heba
    Detection of Thymidine Kinase 1 Activity in Whole Blood Using an Oligonucleotide System2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In today’s medical science studies, many tumor markers are being used to monitor cancer cell proliferation, but the number of assays for analysis of these markers are few. The aim of this study was to find an easier and more time-efficient way to measure the activity of a specific tumor marker called tymidine kinase 1 (TK1). This tumor marker is an important enzyme involved in cell proliferation and is a key enzyme in the salvage pathway. TK1 activity is related to the occurrence of hematological malignancies and cell activity and therefore have been used as a marker when monitoring this group of patients in treatment. Measurement of the enzyme activity in this study was performed by using an oligonucleotide assay. Detection of the enzyme activity in whole blood and in plasma has not previously been shown. The TK1 activity measured in whole blood and plasma correlated with TK1 activity measured in serum (R2=0,8651 and R2 =0,9845, respectively). It was found that it is possible to determine the TK1 activity in whole blood but only if the activity was measured on the same day as the blood samples were taken. The results shows that the activity measurement of TK1 in plasma and whole blood can be used as a marker to verify patients' therapy in cancer care. This study is only the beginning and further investigations should be made in the future to determine if the method that is subject to this study has the requested effects.

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  • 5.
    Abdirashid, Abdulle
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Detektion av kloratreduktas och kloritdismutas med hjälp av 2D elektrofores2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 6.
    Abdullah, Sara Alawi
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Lång respektive fördröjd provtransport ger försämrad blodprovskvalitet2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 7.
    Abdulleteef, Lina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Förekomst av humant papillomvirus i tonsillcancer i norra regionen i Sverige 2000-20122013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 8.
    Abedan Kondori, Farid
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Liu, Li
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    3D Active Human Motion Estimation for Biomedical Applications2012In: World Congress on Medical Physics and Biomedical Engineering May 26-31, 2012, Beijing, China / [ed] Mian Long, Springer Berlin/Heidelberg, 2012, , p. 4p. 1014-1017Conference paper (Refereed)
    Abstract [en]

    Movement disorders forbid many people from enjoying their daily lives. As with other diseases, diagnosis and analysis are key issues in treating such disorders. Computer vision-based motion capture systems are helpful tools for accomplishing this task. However Classical motion tracking systems suffer from several limitations. First they are not cost effective. Second these systems cannot detect minute motions accurately. Finally they are spatially limited to the lab environment where the system is installed. In this project, we propose an innovative solution to solve the above-mentioned issues. Mounting the camera on human body, we build a convenient, low cost motion capture system that can be used by the patient while practicing daily-life activities. We refer to this system as active motion capture, which is not confined to the lab environment. Real-time experiments in our lab revealed the robustness and accuracy of the system.

  • 9.
    Abelson, Klas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Acetylcholine in Spinal Pain Modulation: An in vivo Study in the Rat2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The spinal cord is an important component in the processing and modulation of painful stimuli. Nerve signals from the periphery are relayed and further conducted to the brain (nociception) in the spinal cord, and the most essential modulation of painful information (antinociception) occurs here. Several neurotransmitters are involved in spinal pain modulation, among them acetylcholine. However, the role of acetylcholine has previously been little investigated.

    In the present thesis, the acetylcholine release in the spinal cord was studied in vivo. By using spinal microdialysis on anaesthetised rats, the effects on the intraspinal acetylcholine release of various receptor ligands and analgesic agents were examined. This, together with pain behavioural tests and in vitro pharmacological assays, was used to evaluate the role of acetylcholine in spinal pain modulation. The four studies in this thesis resulted in the following conclusions:

    An increased release of spinal acetylcholine is associated with an elevated pain threshold, while a decreased acetylcholine release is associated with hyperalgesia, as seen after systemic treatment with a muscarinic agonist and an antagonist.

    Lidocaine is a potent analgesic when given systemically. It was found to produce an increase of intraspinal acetylcholine after intravenous injection of analgesic doses. This effect was attenuated after muscarinic, and abolished after nicotinic, receptor blockade.

    Various a2-adrenergic ligands, associated with nociceptive or antinociceptive effects, were found to affect intraspinal acetylcholine release via action on nicotinic receptors.

    Finally, the involvement of spinal acetylcholine in the analgesic effects of aspirin and paracetamol was examined. It was found that spinal acetylcholine could participate in the analgesic effects of aspirin, but not of paracetamol.

    The present thesis provides data that clearly demonstrate a relationship between intraspinal acetylcholine and antinociception, and elucidate interactions between acetylcholine and other mechanisms that mediate antinociception in the spinal cord.

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    COVER01
  • 10.
    Abelson, Klas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Hau, Jann
    Carlsson, Hans-Erik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Undergraduate and postgraduate students' responses to mandatory courses (FELASA category C) in laboratory animal science 1997-20032005In: Internationalisation and Harmonisation of Laboratory Animal Care and Use Issues: Proceedings of the Ninth FELASA Symposium 14-17 June 2004, Nantes, France / [ed] M. R. Gamble, 2005Conference paper (Other academic)
  • 11.
    Abelson, Klas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Höglund, Urban
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Intravenously administered lidocaine in therapeutic doses increases the intraspinal release of acetylcholine in rats2002In: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 317, no 2, p. 93-6Article in journal (Refereed)
    Abstract [en]

    The local anesthetic lidocaine suppresses different pain conditions when administered systemically. Part of the antinociceptive effect appears to be mediated via receptor mechanisms. We have previously shown that muscarinic and nicotinic agonists that produce antinociception increase the intraspinal release of acetylcholine. In the present study it was hypothesized that systemically administered lidocaine is acting through the same mechanisms as cholinergic agonists and affects the intraspinal release of acetylcholine. Microdialysis probes were placed in anesthetized rats for sampling of acetylcholine. Ten and 30 mg/kg lidocaine injected intravenously significantly increased the intraspinal release of acetylcholine. The effect of lidocaine could be reduced by pretreatment with intraspinally administered atropine or mecamylamine. Our results suggest that the antinociceptive effect produced by systemically administered lidocaine is mediated through an action on muscarinic and nicotinic receptors.

  • 12.
    Abelson, Klas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Höglund, Urban
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Intravenously administered oxotremorine and atropine, in doses known to affect pain threshold, affect the intraspinal release of acetylcholine in rats2002In: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 90, no 4, p. 187-192Article in journal (Refereed)
    Abstract [en]

    Abstract:Both systemically and intrathecally administered cholinergic agonists produce antinociception while cholinergic antagonists decrease pain threshold. The mechanism and the site of action of these substances are not known. In the present study it was hypothesized that systemically administered muscarinic agonists and antagonists modify nociceptive threshold by affecting intraspinal release of acetylcholine (ACh). Catheters were inserted into the femoral vein in rats maintained on isoflurane anaesthesia for administration of oxotremorine (10–300 μg/kg) and atropine (0.1, 10, 5000 μg/kg). Spinal microdialysis probes were placed intraspinally at approximately the C2–C5 spinal level for sampling of acetylcholine and dialysis delivery of atropine (0.1, 1, 10 nM). Additionally, the tail-flick behaviour was tested on conscious rats injected intraperitoneally with saline, atropine (10, 100 and 5000 μg/kg), or subcutaneously with oxotremorine (30, 100, 300 μg/kg). Subcutaneous administration of oxotremorine (30, 100, 300 μg/kg) significantly increased the tail-flick latency. These doses of oxotremorine dose-dependently increased the intraspinal release of acetylcholine. Intravenously administered atropine, in a dose that produced hyperalgesia (5000 μg/kg) in the tail-flick test, significantly decreased the intraspinal release of acetylcholine. Our results suggest an association between pain threshold and acetylcholine release in spinal cord. It is also suggested that an approximately 30% increase in basal ACh release produces antinociception and that a 30% decrease in basal release produces hyperalgesia.

  • 13.
    Abelson, Klas
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Höglund, Urban
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    The effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine, and antagonists yohimbine and efaroxan, on the spinal cholinergic receptor system in the rat2004In: Basic & Clinical Pharmacology & Toxicology, ISSN 1742-7835, E-ISSN 1742-7843, Vol. 94, no 4, p. 153-60Article in journal (Refereed)
    Abstract [en]

    Cholinergic agonists produce spinal antinociception via mechanisms involving an increased release of intraspinalacetylcholine. The cholinergic receptor system interacts with several other receptor types, such as a2-adrenergic receptors.To fully understand these interactions, the effects of various receptor ligands on the cholinergic system must be investigatedin detail. This study was initiated to investigate the effects of the a2-adrenergic receptor agonists clonidine and rilmenidineand the a2-adrenergic receptor antagonists yohimbine and efaroxan on spinal cholinergic receptors in the rat. Spinalmicrodialysis was used to measure in vivo changes of acetylcholine after administration of the ligands, with or withoutnicotinic receptor blockade. In addition, in vitro binding properties of the ligands on muscarinic and nicotinic receptorswere investigated. It was found that clonidine and rilmenidine increased, while yohimbine decreased spinal acetylcholinerelease. Efaroxan affected acetylcholine release differently depending on concentration. Nicotinic receptor blockade atten-uated the effect of all ligands. All ligands showed poor binding affinity for muscarinic receptors. On the other hand, allligands possessed affinity for nicotinic receptors. Clonidine and yohimbine binding was best fit to a one site binding curveand rilmenidine and efaroxan to a two site binding curve. The present study demonstrates that the tested a2-adrenergicreceptor ligands affect intraspinal acetylcholine release in the rat evoked by nicotinic receptor mechanisms in vivo, andthat they possess binding affinity to nicotinic receptors in vitro. The binding of a2-adrenergic receptor ligands to nicotinicreceptors might affect the intraspinal release of acetylcholine.

  • 14.
    Abelson, Klas
    et al.
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Neuroscience, Comparative Medicine.
    Kommalage, Mahinda
    Höglund, Urban
    Spinal cholinergic involvement after treatment with aspirin and paracetamol in rats2004In: Neuroscience Letters, ISSN 0304-3940, Vol. 368, no 1, p. 116-120Article in journal (Refereed)
  • 15.
    Abezie, Henock
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Preanalytisk inverkan av provtagningsrör vid zinkanalys i plasma2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 16.
    Aboul-Enein, Mohamed N.
    et al.
    Natl Res Ctr, Pharmaceut & Drug Ind Res Div, Med & Pharmaceut Chem Dept, Med Chem Grp, Giza 12622, Egypt..
    El-Azzouny, Aida A.
    Natl Res Ctr, Pharmaceut & Drug Ind Res Div, Med & Pharmaceut Chem Dept, Med Chem Grp, Giza 12622, Egypt..
    Attia, Mohamed I.
    Natl Res Ctr, Pharmaceut & Drug Ind Res Div, Med & Pharmaceut Chem Dept, Med Chem Grp, Giza 12622, Egypt.;King Saud Univ, Coll Pharm, Dept Pharmaceut Chem, Riyadh 11451, Saudi Arabia..
    Maklad, Yousreya A.
    Natl Res Ctr, Pharmaceut & Drug Ind Res Div, Med & Pharmaceut Chem Dept, Pharmacol Grp, Giza 12622, Egypt..
    Amin, Kamilia M.
    Cairo Univ, Fac Pharm, Dept Pharmaceut Chem, Cairo, Egypt..
    Abdel-Rehim, Mohamed
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    El-Behairy, Mohammed F.
    Natl Res Ctr, Pharmaceut & Drug Ind Res Div, Med & Pharmaceut Chem Dept, Med Chem Grp, Giza 12622, Egypt..
    Design and synthesis of novel stiripentol analogues as potential anticonvulsants2012In: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 47, p. 360-369Article in journal (Refereed)
    Abstract [en]

    A series of stiripentol (SIP) analogues namely, 2-1(1E)-1-(1,3-benzodioxol-5-yl)-4,4-dimethylpent-1-en-3-ylidene]-N-(aryl/H)hydrazinecarboxamides 7a-h, (+/-)-(5RS)-N-(aryl/H)-(1,3-benzodioxol-5-yl)-3-tert-butyl-4,5-dihydro-1H-pyrazole-1-carboxamides (+/-)-8a-h, and (+/-)-[(5RS)-(1,3-benzodioxol-5-yl)-3-tert-butyl-4,5-dihydro-1H-pyrazol-1-yl](aryl)methanones (+/-)-13a-f was synthesized by adopting appropriate synthetic routes and was pharmacologically evaluated in the preliminary anticonvulsant screens. The selected bioactive new chemical entities were subjected to ED50 determination and neurotoxicity evaluation. The most active congeners are 7h in MES screen and (+/-)-13b in scPTZ screen which displayed ED50 values of 87 and 110 mg/kg, respectively, as compared to that of STP (ED50 = 277.7 and 115 mg/kg in MES and scPTZ, respectively). (C) 2011 Elsevier Masson SAS. All rights reserved.

  • 17.
    Abrahamsson, Karolina
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Detektion av herpesvirus i hjärnvävnad med q-PCR: Utvärdering av KAPA Express Extract kit och KAPA PROBE FORCE q-PCR kit2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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    omslag
  • 18.
    Abrahamsson, Pernilla
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Johansson, Göran
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Åberg, Anna-Maja
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Winsö, Ola
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Anaesthesiology.
    Blind, Per Jonas
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Outcome of microdialysis sampling on liver surface and parenchyma2016In: Journal of Surgical Research, ISSN 0022-4804, E-ISSN 1095-8673, Vol. 200, no 2, p. 480-487Article in journal (Refereed)
    Abstract [en]

    Background: To investigate whether surface microdialysis (μD) sampling in probes covered by a plastic film, as compared to noncovered and to intraparenchymatous probes, would increase the technique's sensitivity for pathophysiologic events occurring in a liver ischemia-reperfusion model. Placement of μD probes in the parenchyma of an organ, as is conventionally done, may cause adverse effects, e.g., bleeding, possibly influencing outcome.

    Methods: A transient ischemia-reperfusion model of the liver was used in six anesthetized normoventilated pigs. μD probes were placed in the parenchyma and on the liver surface. Surface probes were either left uncovered or were covered by plastic film.

    Results: Lactate and glucose levels were significantly higher in plastic film covered probes than in uncovered surface probes throughout the ischemic period. Glycerol levels were significantly higher in plastic film covered probes than in uncovered surface probes at 30 and 45 min into ischemia.

    Conclusions: Covering the μD probe increases the sensibility of the μD–technique in monitoring an ischemic insult and reperfusion in the liver. These findings confirm that the principle of surface μD works, possibly replacing need of intraparenchymatous placement of μD probes. Surface μD seemingly allows, noninvasively from an organ's surface, via the extracellular compartment, assessment of intracellular metabolic events. The finding that covered surface μD probes allows detection of local metabolic changes earlier than do intraparenchymatous probes, merit further investigation focusing on μD probe design.

  • 19.
    Abshir, Hawa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Evaluating the Accuracy of Chloride Meters, The ChloroChek instrument in Sweat Testing for Cystic Fibrosis2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Cystic fibrosis (CF) is a hereditary disorder caused by genetic mutations, which affect the chloride ion channels, leading to disrupted salt balance in different organs. A lack of properly functioning chloride ion channels can lead to formation of thick mucus, which hinders organ function, especially in the lungs where repeated inflammation occurs. Early diagnosis is critical to prevent further deterioration of the patient's condition. Current method of analysis of CF diagnostics uses conductivity meters to measure sweat electrolytes. However, current guidelines suggest using a chloridometer to directly measure chloride concentration, is the most reliable marker of cystic fibrosis. The aim of this project was to conduct a comprehensive evaluation of the new instrument's safety, reliability, validity, and conformity of the reference range to international chloride meter guidelines. Additional aims were to investigate the effect of storage conditions on sweat chloride concentration levels and examine the effect of increased salt intake on sweat test results. The study recruited healthy participants and took samples of their sweat by inducing sweat gland secretion. The chloride ion concentration was determined using a coulometric method.

    The results of the study found that the new method was reliable and matched international protocols. It also revealed that an increased salt consumption can impact chloride concentration in sweat, but not to an extent that it can affect medical decisions. Additionally, the study demonstrated that sweat samples can be frozen for up to two weeks without affecting the outcome of the chloride determination. 

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  • 20. Abtahi, F
    et al.
    Seoane, F
    University of Borås, School of Engineering.
    Lindecrantz, K
    University of Borås, School of Engineering.
    Electrical bioimpedance spectroscopy in time-variant systems: Is undersampling always a problem?2014In: Journal of Electrical Bioimpedance, E-ISSN 1891-5469, Vol. 5, no 1, p. 28-33Article in journal (Refereed)
    Abstract [en]

    During the last decades, Electrical Bioimpedance Spectroscopy (EBIS) has been applied mainly by using the frequency-sweep technique, across a range of many different applications. Traditionally, the tissue under study is considered to be time-invariant and dynamic changes of tissue activity are ignored by treating the changes as a noise source. A new trend in EBIS is simultaneous electrical stimulation with several frequencies, through the application of a multi-sine, rectangular or other waveform. This method can provide measurements fast enough to sample dynamic changes of different tissues, such as cardiac muscle. This high sampling rate comes at a price of reduction in SNR and the increase in complexity of devices. Although the frequency-sweep technique is often inadequate for monitoring the dynamic changes in a variant system, it can be used successfully in applications focused on the time-invariant or slowly-variant part of a system. However, in order to successfully use frequency-sweep EBIS for monitoring time-variant systems, it is paramount to consider the effects of aliasing and especially the folding of higher frequencies, on the desired frequency e.g. DC level. This paper discusses sub-Nyquist sampling of thoracic EBIS measurements and its application in the case of monitoring pulmonary oedema. It is concluded that by considering aliasing, and with proper implementation of smoothing filters, as well as by using random sampling, frequency-sweep EBIS can be used for assessing time-invariant or slowly-variant properties of time-variant biological systems, even in the presence of aliasing. In general, undersampling is not always a problem, but does always require proper consideration.

  • 21.
    Abuaita, Areej
    et al.
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    El Saleh, Asmaa
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Utvärdering av analysmetod för bestämning av anti-FXa aktivitet i plasma hos patienter behandlade med apixaban eller LMH2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Apixaban and low molecular weight heparin (LMWH), are anticoagulants that prevent clot formation by inhibiting factor Xa. Increasingly more patients use apixaban and LMWH, for this reason the laboratory medicine at the county hospital Ryhov needs to evaluate methods of analysis for apixaban and LMWH to be able to implement the analyzes in clinical routine. Aim: The purpose of the study was to evaluate the assay method for determining anti-FXa activity in plasma in patients treated with apixaban or LMWH using chromogenic substrate method. Method: The method evaluation consisted of four steps: repeatability, intermediate precision measures, compliance with validated method and analysis of normal population. The evaluation was performed using Sysmex CS-2100 where 20 respective 40 patient samples were analyzed for apixaban and LMWH as well as 10 normal population samples. Factor Xa activity was quantitatively determined using light absorption at 405 nm.Result and discussion: Repeatability and intermediate precision showed low CV. Patient samples showed consistent results with reference values from other laboratories where r2 for apixaban and LMWH were 0.95. Deviant results may be due to measurement errors or confusion between samples. Analysis of normal population showed that values were below the lowest reliable value. Conclusion: Evaluation of the analysis method apixaban and LMWH at Ryhov's laboratory showed good results, which confirms that the assay method can be used in clinical routine.

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  • 22.
    Abucar, Ramla
    Örebro University, School of Health Sciences.
    Utvärdering av prestanda vid olika reaktionsvolymer med QuantStudio qPCR samt jämförelse mellan två pipetteringsrobotar2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Polymerase chain reaction (PCR) is a biochemical and molecular laboratory technique that is used for amplification of specific gene sequences. There are different variants of PCR. A more developed version is quantitative PCR (qPCR). In qPCR the fluorescence intensity is measured in realtime during each qPCR cycle. 

     

    Aim: The purpose of the project is to evaluate whether the reaction volume can be reduced by half, which leads to using less material and thus make the method more cost-effective.

     

    Matherial & method: Synthetic DNA sequence (gBlock) was diluted and set up in a standard curve with seven standards and used for 20 μl and 10 μl reaction volume, respectively. Each standard consisted of 4 replicates. To evaluate Duplex vs Singelplex, standard curve was prepared in combination with a constant concentration of another assay. To investigate intra-plate variation, identical reactions were set up in all wells of the PCR-plate.

     

    Results: All experiments yielded detectable amplification products. The Cq value was used to calculate the mean and standard deviation, as well as the efficiency and R2 value

     

    Conclusion:  The obtained results showed that the reaction volumes 10 and 20 µl are comparable. In duplex assay, genes with low gene expression can be analyzed with genes that have 10,000x higher gene expression. In intraplate-assay variation, the variation in the standard deviation increased in the right side of PCR-plate. 

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  • 23.
    Adamson, Peter
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences (from 2013).
    Inverkan av lipemisk turbiditet på koncentrationsbestämning av IgM och LDL-K i serumprover med VITROS® 4600 samt åtgärdsförslag2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 24.
    Adelholt, Denise
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    The Effects of Cell Culture Medium and Supplements on the Differentiation of Boundary Cap Neural Crest Stem Cells2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Boundary cap neural crest stem cells (bNCSCs) are multipotent cells that form a barrier between CNS and PNS, playing an important role in ingrowth of neurites into the spinal cord during development. Because of the stemness and multipotency of bNCSCs, they self-renew and can be used directly for transplantation or as a source of matured neural cells. It is important that cells used for cell therapy differentiate and develop into the mature cells that the recipient needs. To ensure this, cells are guided towards specific cell fates, and one way of doing this is with medium supplements. The purpose of this study was to analyze the effects of three different media with supplements on the differentiation of bNCSCs. Two cell lineages of bNCSCs expressing green- and red fluorescent protein were treated with different media for differentiation. The effects of the media supplements neurotrophic glial cell line-derived neurotrophic factor (GDNF), cilinary neurotrophic factor (CTNF) and fetal bovine serum (FBS) were compared, with one medium containing no additional factors. It was found that when GDNF and CTNF are supplemented in the differentiation media, bNCSCs are guided towards astrocytes. Interestingly, the medium containing no additional factors gave rise to an even amount of neurons and astrocytes. FBS had an inhibitory effect on overall differentiation of bNCSCs, giving rise to the smallest amount of neurons and astrocytes. The bNCSCs are promising for cell therapy, as their differentiation can be guided with the use of medium supplements.

  • 25. Adinda, Mathia
    Nutrition supplements when undergoing orthopedic surgery2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Malnutrition is prevalent in elderly populations with orthopedic disabilities, which is especially critical during surgery when the body is under much stress. It is important that these patients are well nourished to be able to cope when mechanisms such as immune system are activated. Nutrition is also important after surgery when the body is healing and sometimes struggling against different complications as infections. The aim of this study was to evaluate if nutrition supplements decreases the time needed for rehabilitation and improve the outcome after orthopedic surgeries. This was performed by analyzing biomarkers involved in wound healing. The study population comprised of 100 surgical patients at the age of 50 or older. The participant where divided into two groups, one test group that received nutrition supplements and one control group who did not receive any extra nutrition. Sandwich ELISA was used to measure myostatin, cathepsin S and cathepsin B concentrations in patient serum before and after surgery. There were no significant difference between the control group and the test group for any of the three biomarkers. The conclusion is that nutrition supplement does not decrease the rehabilitation time and outcome according to the results in this study.

  • 26. Adlerz, Linda
    Immunohistochemistry in an automated platform forPrion Protein in Transmissible Spongiform Encephalopathy2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Transmissible spongiform encephalopathies, like Creutzfeldt-Jakobs Diseaseare fatal neurodegenerative disorders. They are caused by misfolding and aggregation of anendogenously expressed protein, prion. Detection of the pathological form of prions byimmunohistochemistry has become a valuable tool for diagnostics. However,immunohistochemistry of prions is traditionally performed manually and with various tediouspretreatments.Purpose: In clinical diagnostics fast, specific, reliable and standardised protocols are needed.In this study an optimised protocol for prion immunohistochemistry in an automated platformwas developed.Material and methods: Sections of paraffin-embedded brain tissue from patients with andwithout sporadic Creutzfeldt-Jakobs Disease was used for comparison withimmunohistochemistry with two different anti-prion antibodies 12F10 and 3F4. The effect ofdifferent pre-treatments like vaporised cooking under pressure, use of proteinase K, citratebuffer, guanidine thiocyanate and picric acid was investigated.Results: Both antibodies displayed similar patterns of immunoreactivity in the manual as wellas in the automated platform. Vaporised cooking under pressure was preferred before heatingin the automated platform due to minimal change in tissue morphology with the former. Theuse of citrate buffer and proteinase K was essential for detecting immunoreactivity whereasguanidine thiocyanate and picric acid could be excluded.Conclusion: Both 12F10 and 3F4 can be used for immunohistochemistry on an automatedplatform for clinical diagnostics. Pre-treatments in this protocol include formic acid,vaporised cooking under pressure in citrate buffer and the use of proteinase K.

  • 27.
    Adolfsson, Karin
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    Visual Evaluation of 3D Image Enhancement2006Independent thesis Basic level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Technologies in image acquisition have developed and often provide image volumes in more than two dimensions. Computer tomography and magnet resonance imaging provide image volumes in three spatial dimensions. The image enhancement methods have developed as well and in this thesis work 3D image enhancement with filter networks is evaluated.

    The aims of this work are; to find a method which makes the initial parameter settings in the 3D image enhancement processing easier, to compare 2D and 3D processed image volumes visualized with different visualization techniques and to give an illustration of the benefits with 3D image enhancement processing visualized using these techniques.

    The results of this work are;

    1. a parameter setting tool that makes the initial parameter setting much easier and

    2. an evaluation of 3D image enhancement with filter networks that shows a significant enhanced image quality in 3D processed image volumes with a high noise level compared to the 2D processed volumes. These results are shown in slices, MIP and volume rendering. The differences are even more pronounced if the volume is presented in a different projection than the volume is 2D processed in.

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  • 28.
    Adolfsson, Viktor
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    Optimization of immunohistochemistry staining of MDM2 and CDK4, to facilitate differential diagnostics of liposarcoma2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 29.
    Afshari, Ali
    et al.
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Saager, Rolf B.
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Burgos, David
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Vogt, William
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Wang, Jianting
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Mendoza, Gonzalo
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Weininger, Sandy
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Sung, Kung-Bin
    National Taiwan University, Graduate Institute of Biomedical Electronics and Bioinformatics, Taipei, Taiwan.
    Durkin, Anthony
    Department of Biomedical Engineering, University of California, Irvine, Natural Sciences II, Irvine, California, USA; Beckman Laser Institute & Medical Clinic, University of California, Irvine, East Irvine, California, USA.
    Pfefer, T. Joshua
    Center for Devices and Radiological Health, Food and Drug Administration, Silver Spring, Maryland, USA.
    Evaluation of the robustness of cerebral oximetry to variations in skin pigmentation using a tissue-simulating phantom2022In: Biomedical Optics Express, E-ISSN 2156-7085, Vol. 13, no 5, p. 2909-2928Article in journal (Refereed)
    Abstract [en]

    Clinical studies have demonstrated that epidermal pigmentation level can affect cerebral oximetry measurements. To evaluate the robustness of these devices, we have developed a phantom-based test method that includes an epidermis-simulating layer with several melanin concentrations and a 3D-printed cerebrovascular module. Measurements were performed with neonatal, pediatric and adult sensors from two commercial oximeters, where neonatal probes had shorter source-detector separation distances. Referenced blood oxygenation levels ranged from 30 to 90%. Cerebral oximeter outputs exhibited a consistent decrease in saturation level with simulated melanin content; this effect was greatest at low saturation levels, producing a change of up to 15%. Dependence on pigmentation was strongest in a neonatal sensor, possibly due to its high reflectivity. Overall, our findings indicate that a modular channel-array phantom approach can provide a practical tool for assessing the impact of skin pigmentation on cerebral oximeter performance and that modifications to algorithms and/or instrumentation may be needed to mitigate pigmentation bias.

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  • 30.
    Aghyad, Dakakni
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Verification of hypochromic erythrocytes on Sysmex XN 20002020Student paper other, 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Anemia is a serious blood disease that more than two billion suffer from worldwide. Half of that number consist of iron deficiency anemia, which is insufficiency of iron supply to the bone marrow due to empty iron store or hampered iron utilization due to inflammation. Therefore, requires rapid diagnosis.

        Analysis parameter for hypochromic erythrocytes (HYPO-He) is a highly applicable parameter for detection of iron deficiency using Sysmex XN 2000. It measures erythrocytes with low hemoglobin concentration. The aim of this study was to verify whether the research parameter HYPO-He should be included as a diagnostic analysis for anemia at the Hudiksvall Clinical Chemistry Laboratory in the Gävleborg Region, Sweden.

        The study material consisted of 34 samples, whole blood with EDTA. Two samples for in-series-imprecision and two for sustainability control. The two control materials (low and normal) and samples with properly filled tubes were analyzed with Sysmex XN in the reticulocyte channel using the optical method, by flow cytometry with laser.

        The results of duplicate sample on Sysmex XN showed that linear regression value R2 was 1.0 and coefficient of variation CV was 0.83 %. During this project, similar results were obtained that other projects had done with different instruments and methods. According to the results, HYPO-He is reliable and useful for improved iron deficiency diagnostics. Additional studies on HYPO-He stability is recommended.

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    HYPO-He
  • 31.
    Agid, Nyroz
    et al.
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Sjöqvist, Evelina
    Jönköping University, School of Health and Welfare, HHJ, Dep. of Natural Science and Biomedicine.
    Prevalence of hookworm infection evaluated with Willis flotation and Formal Ethyl Acetate concentration: A field study in Da Nang, Vietnam2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Hookworm infection can cause nausea, stomach pain and anemia, with the most harmful effect being found among women of reproductive age and children. The infection rates is high in poor parts of the world with a high number of infected in Asia. The infection is many times neglected since it rarely causes mortality, however the morbidity can be destructive. In Vietnam the prevalence of hookworm is largely unknown, but there is believed to be a 29-80 % infection rate in the country. Through a field study in Da Nang, Vietnam, the prevalence of hookworm was identified using two methods, Willis flotation and formal ethyl acetate concentration. Any correlation between hookworm infection and individuals’ gender, age and geographic area was evaluated. A total of 101 consecutive selected samples from hospitals and communities in rural and urban parts of the city were obtained from both gender ranging between 1-72 years in age. No quantitative differences were found between the two methods nor any correlation between genders (p-value 0,143). The overall prevalence was 16,8%. The rural part of the city showed a higher infection rate in contrast to the urban districts (p-value 0,001). Individuals in the age group 25-48 showed a higher infection rate in contrast to the other age groups (p-value 0,035). 

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  • 32.
    Agyemang, Alberta
    Malmö University, Faculty of Health and Society (HS), Department of Biomedical Science (BMV).
    Investigation of vitamin K interaction and transdermal delivery at skin barriers:study using k4 model2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Vitamin K is a fat soluble compound which is synthesized by the gut microbiota and produced in many tissues within the body. Considering its role in the liver as a cofactor for gamma carboxylase enzymes, treatment of dark circles and pigments under the eye among others. It is clear that is some circumstances vitamin K has to cross biological barriers, particularly, when the vitamin is produced by microbiota in the intestine or applied topically on skin. Thus it is important to develop methods that allow studies of vitamin K permeability through the skin including its participation in redox reactions and transdermal permeability. Taking into account that transdermal permeability is strongly limited for high molecular weight compounds, i.e., compounds with higher than 500Da, the study was conducted with vitamin K of  lower molecular weight. Specifically vitamin K4 model, i.e., 1,4-dihydroxy-2 naphthoic acid, with molecular weight of 204g/mol. Vitamin K4 is suitable for this kind of study , because it can work as reducing (antioxidant) compound as well as has relatively beneficial physicochemical characteristics for transdermal permeability. Permeability studies were conducted with skin covered oxygen electrode and franz diffusion cell. Data from measurements were analyzed to estimate diffusion coefficients, apparent Michaelis-Menten constants and flux of a vitamin K4 model whilst contribution of different permeability pathways was determined theoretically.

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  • 33.
    Ahlebrand, August
    Halmstad University, School of Business, Engineering and Science. 920801117.
    Investigating the effects of pre-exhausting a synergist prior to a compound exercise.: An electromyographic study2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Pre-exhausting a synergist prior to a compound exercise has been shown to alter the firing patterns in the muscles during the exercise. Pre-exhausting a muscle is done by exercising a muscle group to fatigue with a single joint exercise prior to an exercise.

    Aim: The purpose of this study was to further investigate the effects of pre-exhausting the triceps brachii prior to performing a bench press, measuring the EMG activity in pectoralis major, triceps brachii and deltoid anterior.

    Methods: 30 participants, men (n=15) and women (n=15), performed two different protocols (T1 and T2) while the muscle activity was measured with surface EMG. Electrodes were placed on pectoralis major, triceps brachii and deltoid anterior. Maximum voluntary isometric contraction (MVIC) was performed prior to performing protocols in order to get reference values.

    Results: Pectoralis major and deltoid anterior activation was significantly higher when preexhausting triceps brachii before bench press compared to no PRE, but no significant increase was seen in triceps brachii (p=0.000, p=.0009 and p=0.405 respectively) MVIC expressed in percentages and mean values ± standard deviation during protocol T1 for pectoralis major 45.3(±12.4), triceps brachii 56.28(±15.9) and deltoid anterior 63.45(±31.4) and during protocol T2 pectoralis major 56.41(±18.4), triceps brachii 58.49(±20.07) and deltoid anterior 71.65(±42.7).

    Conclusion: These results suggest that pre-exhausting a synergist prior to a compound exercise may change the muscle activity in the involved muscles. This can be used in a practical sense to develop weak points in the muscles by changing the activation pattern in the muscles hence being able to target specific muscles better.

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  • 34.
    Ahlgren, Evelina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Retrospective serological and virological survey of influenza D virus among cattle in Sweden2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Respiratory diseases in cattle can cause economic losses due to the decreased dairy and meat production. Virus is the main reason for these diseases. Symptoms can be fever, cough and nasal discharge.

        Influenza are a group of viruses belonged in the Ortomyxoviridae family. The big influenza groups are influenza A, B and C. The viruses can cause respiratory signs, and mammals can be affected. Recently a new influenza virus was found in the United States. The influenza virus was found in swine, but the natural host was later considered to be cattle. The virus was named influenza D. Different studies worldwide have confirmed the virus in a variety of regions. Antibodies have also been reported.

        In this study, virologic and serologic methods were used to detect if influenza D circulates among cattle in Sweden. The serologic method performed was indirect ELISA. Serum and milk samples were investigated in the ELISA method. For the virologic detection a real-time RT-PCR was made, with a variety of study material.

        Antibodies against influenza D were found in both serum and milk samples. No virus was found in the real-time RT-PCR. In Sweden the animal keeping is different compared to several other nations. For instance, the conditions of health and hygiene are better in Sweden, this may be an important cause of a system more resistant against spreading of infections. Influenza D could be more common in Sweden, but in that case further researches are needed to determine the prevalence.

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  • 35. Ahlin, Jennifer
    Evaluation of the platelet yield index on interim platelet units from Reveos by comparison with platelet count from Sysmex2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Platelets are the smallest cells in the blood and are involved in the wound healing process. Platelet transfusion is an important part of treating illnesses such as thrombocytopenia and to prevent and stop major bleedings. Platelets for transfusion are received after processing of whole blood through automated or semi-automated systems and pooling of interim platelet units received after the processing. A limit is set for the minimum total estimated platelet yield in a pool to ensure that the final product consists of enough platelets.

    Aim: The aim of this study was to evaluate the platelet yield index received from Reveos automatic blood processing system by comparing it to the fluorescent flow cytometry method on Sysmex cell counter. 

    Material and method: Whole blood from 147 donors were processed in the Reveos automated blood processing system into the separate components. All the interim platelet units received a platelet yield index from Reveos. A sample from each interim platelet unit was collected and analyzed on Sysmex in the channel for fluorescent flow cytometry.

    Result: The difference between the platelet count from the two methods was 45 ±26 x109/unit (p<0,001). Platelet yield index from Reveos was 67 ±17 x109/unit and the platelet count from Sysmex was 112 ±35 x109/unit. The r2 from the scattergram was 0,49.

    Conclusion: The platelet yield index from Reveos underestimates the platelet yield compared to fluorescent flow cytometry from Sysmex. The limit for the total platelet yield in a pool of interim platelet units could therefore be decreased.

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  • 36.
    Ahlström, Christer
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Processing of the Phonocardiographic Signal: methods for the intelligent stethoscope2006Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    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.

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  • 37.
    Ahmed, Aden
    Kristianstad University, School of Education and Environment.
    Utveckling av en PCR-baserad metod för detektion av plasmidburna kolistinresistens, mcr-1 och mcr-3 gener i extended-spectrum beta-lactamase (ESBL)-producerande enterobacteriaceae2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kolistin är ett gammalt polypeptidantibiotikum och används som sista utväg för behandling av allvarliga infektioner orsakad av multiresistenta gramnegativa bakterier. Nya studier har påvisat kolistinresistensgener, mcr (mobil colistin resistance), hos extended spectrum beta-lactamase (ESBL)-producerande Enterobacteriaceae. Mcr-genen ligger i plasmider som kan överföras mellan bakterier, vilket innebär att det är mycket svårare att behandla människor och djur vid infektion orsakad av patogen som erhållit denna resistens. Syfte med detta projekt var att utveckla en PCR-baserad metod för detektion av mcr-1 och mcr-3 gener. I denna studie optimerades en PCR-metod och sedan screenades 60 ESBL-isolat från Kristianstads vattenrike. Därefter undersöktes PCR-produkt med hjälp av agarosgelselektrofores. Resultatet visade att 51oC är den optimala annealingtemperaturen vid multiplex-PCR för detektion av mcr-1 och mcr-3. Ingen av mcr-generna kunde detekteras i de 60 ESBL-isolaten. Positiva kontrollstammar med specifika primers kunde detekteras i PCR-analyser som genomfördes i denna studie, vilket tyder på att den optimerade PCR metoden kan vara pålitlig för detektion av mcr-1 och mcr-3 generna.

     

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  • 38.
    Ahmed, Ahmed Hussein Ahmed
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Metodjämförelse mellan laboratoriebaserat instrument och tre patientnära tester vid drogscreening av urin2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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    omslag
  • 39.
    Ajalloueian, Fatemeh
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Zeiai, Said
    Fossum, Magdalena
    Hilborn, Jöns G.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Constructs of electrospun PLGA, compressed collagen and minced urothelium for minimally manipulated autologous bladder tissue expansion2014In: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 35, no 22, p. 5741-5748Article in journal (Refereed)
    Abstract [en]

    Bladder regeneration based on minced bladder mucosa in vivo expansion is an alternative to in vitro culturing of urothelial cells. Here, we present the design of a hybrid, electrospun poly(lactic-co-glycolide) (PLGA) - plastically compressed (PC) collagen scaffold that could allow in vivo bladder mucosa expansion. Optimisation of electrospinning was performed in order to obtain increased pore sizes and porosity to consolidate the construct and to support neovascularisation and tissue ingrowth. Tensile tests showed an increase in average tensile strength from 0.6 MPa for PC collagen to 3.57 MPa for the hybrid construct. The optimised PLGA support scaffold was placed between two collagen gels, and the minced tissue was distributed either on top or both on top and inside the construct prior to PC; this was then cultured for up to four weeks. Morphology, histology and SEM demonstrated that the construct maintained its integrity throughout cell culture. Cells from minced tissue migrated, expanded and re-organised to a confluent cell layer on the top of the construct after two weeks and formed a multilayered urothelium after four weeks. Cell morphology and phenotype was typical for urothelial mucosa during tissue culture. (C) 2014 Elsevier Ltd. All rights reserved.

  • 40.
    Akash, Hala
    Örebro University, School of Health Sciences.
    Jämförelse av motorisk ledningshastighet och proximal latenstid i underarmen och över armbågen samt mellan höger och vänster arm i nervus ulnaris2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: The peripheral nervous system consists of the autonomic nervous system and the peripheral nerve fibers that mediate afferent and efferent impulses between the central nervous system and the peripheral part of the body. From the brachial plexus, the ulnar nerve branches and continues along the arm to the ulnar part of the hand. The most common and largest peripheral nerve injury in the upper extremities is ulnar nerve injury.

    Aim: The aim of the study was to investigate whether there is any significant difference in motor conduction velocity (MCV) between the forearm and above the elbow on the ulnar nerve bilaterally. Also, to compare MCV and proximal latency between right and left forearm and above elbow.

    Method: To answer the purpose, a cross-sectional study was performed on 30 healthy participants aged 20–40 years. The ulnar nerve was examined with electroneurography bilaterally.

    Results: The result showed that there is a significant difference in MCV between the forearm and above the elbow bilaterally on the ulnar nerve. A significant difference in MCV was demonstrated between the right and left sides over the elbow, but not on the forearm. There was no significant difference in the proximal latency between the right and left forearm and above the elbow.

    Conclusion: The significant differences obtained in MCV between forearm and above elbow and between right and left side above elbow may be due to the simulation technique. Such as the arm position during the stimulation and that upper arms are generally more difficult to examine. This entails a greater risk of error sources that can affect the result.

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    Jämförelse av motorisk ledningshastighet och proximal latenstid i underarmen och över armbågen samt mellan höger och vänster arm i nervus ulnaris
  • 41.
    Akdag, Ajda
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Cell Biology.
    The association between oral tamoxifen treatment and cell differentiation in vaginal mucosa2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Introduction: Women diagnosed with estrogen-receptor-positive breast cancer are treated with antiestrogens, for example tamoxifen or aromatase inhibitor, to reduce the risk of the cancer spreading or recurring. A common side effect of antiestrogen treatment is vaginal atrophy symptoms such as vaginal dryness, itching, and pain, since estrogen is important in the regulation of cell proliferation as well as cell differentiation in the female genitalia. The aim of this project was to study the association between tamoxifen treatment and vaginal mucosal cell differentiation in women with estrogen-receptor-positive breast cancer to gain a better understanding of the possible effect of tamoxifen in the genital tract.

    Methods: In this study, vaginal biopsies from four different study groups were used: breast cancer patients treated with tamoxifen (n = 24), breast cancer patients with tamoxifen treatment plus vaginal estrogen (n = 8), control group consisting of healthy postmenopausal women without treatment (n = 37), or with vaginal estrogen (n = 29). Immunohistochemistry was used to study the staining intensity of the differentiation markers filaggrin and involucrin in the vaginal mucosa. 

    Results: The results of the study showed no significant differences between any of the study groups regarding the staining intensity of involucrin in the vaginal mucosa. Filaggrin results were excluded due to unreliable results.

    Conclusions: The results indicate that no negative association between tamoxifen treatment and cell differentiation in the vaginal mucosa could be observed, which may be due to the agonistic effects of tamoxifen on estrogen receptors in vaginal tissue. 

    Keywords: Antiestrogen treatment; Breast cancer; Estrogen receptor; Filaggrin; Involucrin.  

  • 42.
    Akgun, Kocere Kurdé
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Evaluation of Different Extraction- and Analysis Methods for Calprotectin in Feces2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background Calprotectin is a protein expressed in the cytoplasm inside the neutrophile granulocytes. During inflammatory bowel disease (IBD), the neutrophile granulocytes are involved in a complex interaction at the inflammatory area where they die and release their content into the intestinal lumen. Therefore, calprotectin in stool is a suitable marker for diagnosis and measurement of the disease-activity in patients with IBD. The most commonly used method to detect calprotectin in stool is ELISA, but the process of manual preparation of stool samples is time-consuming.

    Aim The objective of the study was to evaluate an extraction method that could replace manual preparation of fecal samples and to compare different methods for measuring Calprotectin in stool using two ELISA-methods from two manufacturers and one rapidtest.

    Methods For extraction of calprotectin from stool samples we used sample collector tubes from Epitope Diagnostics and fecal preparation kits from Roche. Two different ELISA-kits for measuring calprotectin concentration in stool were compared. Measurements of calprotectin with rapid-test from Epitope Diagnostics were also performed and were compared with the two ELISA kits.

    Results The results indicate a poor correlation between two extraction methods with Sample Collector Tube and Roche preparation kit. The comparison between the two ELISA-kits showed poor correlation. Evaluation of rapid test showed 33% false negative results with a cut-off value at 50 mg/kg.

    Conclusion Evaluation of products from Epitope Diagnostics showed poor correlation with the Bühlmann ELISA and an unreliable rapid test. Therefore, none of evaluated products from Epitope Diagnostics is accurate enough to be used for clinical diagnosis in the laboratory.

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  • 43.
    Akhras, Michael S.
    et al.
    Stanford Genome Technol Ctr, Stanford Univ, Palo Alto CA, USA.
    Pettersson, Erik
    Stanford Genome Technol Ctr, Stanford Univ, Palo Alto CA, USA.
    Diamond, Lisa
    Stanford Genome Technol Ctr, Stanford Univ, Palo Alto CA, USA.
    Unemo, Magnus
    Örebro University Hospital.
    Okamoto, Jennifer
    Dept Bioengn, Stanford Univ, Stanford CA, USA.; Howard Hughes Med Inst, Stanford Univ, Stanford CA, USA.
    Davis, Ronald W.
    Stanford Genome Technol Ctr, Stanford Univ, Palo Alto CA , USA.
    Pourmand, Nader
    Dept Biomol Engn, University of California, Santa Cruz CA, USA.
    The Sequencing Bead Array (SBA), a Next-Generation Digital Suspension Array2013In: PLOS ONE, E-ISSN 1932-6203, Vol. 8, no 10, article id UNSP e76696Article in journal (Refereed)
    Abstract [en]

    Here we describe the novel Sequencing Bead Array (SBA), a complete assay for molecular diagnostics and typing applications. SBA is a digital suspension array using Next-Generation Sequencing (NGS), to replace conventional optical readout platforms. The technology allows for reducing the number of instruments required in a laboratory setting, where the same NGS instrument could be employed from whole-genome and targeted sequencing to SBA broad-range biomarker detection and genotyping. As proof-of-concept, a model assay was designed that could distinguish ten Human Papillomavirus (HPV) genotypes associated with cervical cancer progression. SBA was used to genotype 20 cervical tumor samples and, when compared with amplicon pyrosequencing, was able to detect two additional co-infections due to increased sensitivity. We also introduce in-house software Sphix, enabling easy accessibility and interpretation of results. The technology offers a multi-parallel, rapid, robust, and scalable system that is readily adaptable for a multitude of microarray diagnostic and typing applications, e. g. genetic signatures, single nucleotide polymorphisms (SNPs), structural variations, and immunoassays. SBA has the potential to dramatically change the way we perform probe-based applications, and allow for a smooth transition towards the technology offered by genomic sequencing.

  • 44.
    Akula, Ilona
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Hjärtfunktion vid ärftlig transtyretin-amyloidos: Jämförelse av hjärtfrekvensvariabilitet och ekokardiografi mellan två amyloidfibrilltyper2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 45.
    Akula, Srinivas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology.
    Mohammadamin, Sayran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology.
    Hellman, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Chemical Biology.
    Fc Receptors for Immunoglobulins and Their Appearance during Vertebrate Evolution2014In: PLOS ONE, E-ISSN 1932-6203, Vol. 9, no 5, p. e96903-Article in journal (Refereed)
    Abstract [en]

    Receptors interacting with the constant domain of immunoglobulins (Igs) have a number of important functions in vertebrates. They facilitate phagocytosis by opsonization, are key components in antibody-dependent cellular cytotoxicity as well as activating cells to release granules. In mammals, four major types of classical Fc receptors (FcRs) for IgG have been identified, one high-affinity receptor for IgE, one for both IgM and IgA, one for IgM and one for IgA. All of these receptors are related in structure and all of them, except the IgA receptor, are found in primates on chromosome 1, indicating that they originate from a common ancestor by successive gene duplications. The number of Ig isotypes has increased gradually during vertebrate evolution and this increase has likely been accompanied by a similar increase in isotype-specific receptors. To test this hypothesis we have performed a detailed bioinformatics analysis of a panel of vertebrate genomes. The first components to appear are the poly-Ig receptors (PIGRs), receptors similar to the classic FcRs in mammals, so called FcRL receptors, and the FcR gamma chain. These molecules are not found in cartilagous fish and may first appear within bony fishes, indicating a major step in Fc receptor evolution at the appearance of bony fish. In contrast, the receptor for IgA is only found in placental mammals, indicating a relatively late appearance. The IgM and IgA/M receptors are first observed in the monotremes, exemplified by the platypus, indicating an appearance during early mammalian evolution. Clearly identifiable classical receptors for IgG and IgE are found only in marsupials and placental mammals, but closely related receptors are found in the platypus, indicating a second major step in Fc receptor evolution during early mammalian evolution, involving the appearance of classical IgG and IgE receptors from FcRL molecules and IgM and IgA/M receptors from PIGR.

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    fulltext
  • 46.
    Al Hwamdeh, Yaseen
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Urinary Stone Diagnosis Non: Contrast Computed Tomography versus Intravenous Urography2015Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
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    Urinary Stone Diagnosis Non
  • 47.
    Al Rabiey, Ahmed
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Detektion av aktin i paraffinsnitt från human vävnad2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 48.
    Alahmad, Fatima
    Örebro University, School of Health Sciences.
    Stabilitet av alkoholmarkören fosfatidyletanol i torkat filterpapper2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Phosphatidylethanol (PEth) is a phospholipid that is formed in red blood cells only in the presence of ethanol, making the clinical specificity of PEth as an alcohol marker theoretically 100%. The purpose of this study was to investigate the stability of PEth in dried filter paper compared to PEth in whole blood, which is a reference method. Materials used were excess volumes from eight clinical blood samples sent to the laboratory medicine (Unilabs AB, Eskilstuna, Sweden) for PEth analysis and blood samples were taken on dried filter paper from three test subjects; two who consumed alcohol, and one who did not consume alcohol. In addition, stability was studied in commercial preparations, as well as long-term stored, frozen samples. Samples from both commercial preparations and the three test subjects were stored at two temperatures - 20 and 4–5°C - and then analyzed after 14- and 20-days Clinical samples were stored at - 20 °C - and analyzed after 20 days. The result showed a large deviation from the initial value, both for whole blood and filter paper at different temperature conditions (20 °C and 4–8 °C) for the test subjects during a 14- and 20-day period. An increase in PEth values was seen in both whole blood and filter paper at all storage conditions. In contrast, there was little difference between PEth content in whole blood and PEth content on filter paper for the eight clinical patient samples stored at 20°C and analyzed after 20 days. The results from both commercial preparations and long-term samples also showed good stability in both whole blood and dried filter paper. The stability of dried filter paper in the test subjects should be investigated in a new study with more observations.

  • 49.
    Al-Asafi, Zainab
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Förekomst av Mycobacterium avium i vattenprover från barns närmiljö: med fokus på badleksaker2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Mycobacteria are gram-positive bacteria belonging to the Mycobacteriaceae family. There are more than 50 different species of the mycobacteria which can cause diseases in humans, the most important one being M. tuberculosis. Non-tuberculous mycobacteria are also called environmental mycobacteria. Some species can survive in areas with very low amounts of nutrients along with aquatic areas, such as water, dirt, swamps, and marshes. Some environmental mycobacteria are pathogenic and can cause diseases in humans and animals. They are mostly opportunistic pathogens, i.e. they infect humans with an already weakened immune system or humans who suffer from chronic diseases. Two species of mycobacteria named Mycobacterium avium avium and Mycobacterium avium hominissuis belong to the subgroup Mycobacterium avium complex (MAC). Healthy children between the ages of 1 and 5 are an exposed group to MAC-infections. When these children are infected with MAC, they develop an inflammation in the lymph nodes (Lymphadenitis) in the neck area. Since no direct transmission between humans has been established, it has been speculated that the MAC-bacteria take a different route to reach and infect adults and children with lymphadenitis. It has been hypothesized that MAC infect humans through nature and drinking water.

    The purpose of this study was to develop a method to detect the occurrence of M. avium bacteria in tap water from Öland, Kalmar, and Hultsfred, incubated in rubber ducks. The purpose was also to investigate experimentally if M. avium can survive and/or thrive in a rubber duck environment. The methods which have been evaluated in the study were cultivation followed by detection by MALDI-TOF and also triplex q-PCR.  

    The study was done on clean (new) and contaminated (used) rubber ducks with tap water from Öland, Kalmar, and Hultsfred, where some rubber ducks were injected with known strains from M. avium avium and M. avium hominissuis and incubated for five weeks. DNA was extracted from the water and biofilm samples from each rubber duck, for further analysis with q-PCR. Furthermore, a culture from the same water samples was made on nutritious agar for later detection by MALDI-TOF.

    The results of this study using q-PCR showed detection of the bacteria M. avium avium and M. avium hominissuis in all the samples. A possible, and believable, reason for this could be that the extraction solutions used in this study were contaminated. However, the study show that the mycobacteria survive in rubber duck environment.

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  • 50.
    Alavuotunki, Meiju-Maari
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Biomedical Laboratory Science.
    Utveckling av små heterocykler vilka inhiberar gonokocker, MRSA och VRE2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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