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  • 1.
    Asan, Noor Badariah
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics. Univ Tekn Malaysia Melaka, Fac Elect & Comp Engn, Durian Tunggal 76100, Malaysia.
    Hassan, Emadeldeen
    Umea Univ, Dept Comp Sci, S-90187 Umea, Sweden;Menoufia Univ, Dept Elect & Elect Commun, Menoufia 32952, Egypt.
    Perez, Mauricio David
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Shah, Syaiful Redzwan Mohd
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Velander, Jacob
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Blokhuis, Taco J.
    Maastricht Univ, Dept Surg, Med Ctr, NL-6229 HX Maastricht, Netherlands.
    Voigt, Thiemo
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Architecture and Computer Communication. ¨.
    Augustine, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Assessment of Blood Vessel Effect on Fat-Intrabody Communication Using Numerical and Ex-Vivo Models at 2.45 GHZ2019In: IEEE Access, E-ISSN 2169-3536, Vol. 7, p. 89886-89900Article in journal (Refereed)
    Abstract [en]

    The potential offered by the intra-body communication (IBC) over the past few years has resulted in a spike of interest for the topic, specifically for medical applications. Fat-IBC is subsequently a novel alternative technique that utilizes fat tissue as a communication channel. This work aimed to identify such transmission medium and its performance in varying blood-vessel systems at 2.45 GHz, particularly in the context of the IBC and medical applications. It incorporated three-dimensional (3D) electromagnetic simulations and laboratory investigations that implemented models of blood vessels of varying orientations, sizes, and positions. Such investigations were undertaken by using ex-vivo porcine tissues and three blood-vessel system configurations. These configurations represent extreme cases of real-life scenarios that sufficiently elucidated their principal influence on the transmission. The blood-vessel models consisted of ex-vivo muscle tissues and copper rods. The results showed that the blood vessels crossing the channel vertically contributed to 5.1 dB and 17.1 dB signal losses for muscle and copper rods, respectively, which is the worst-case scenario in the context of fat-channel with perturbance. In contrast, blood vessels aligned-longitudinally in the channel have less effect and yielded 4.5 dB and 4.2 dB signal losses for muscle and copper rods, respectively. Meanwhile, the blood vessels crossing the channel horizontally displayed 3.4 dB and 1.9 dB signal losses for muscle and copper rods, respectively, which were the smallest losses among the configurations. The laboratory investigations were in agreement with the simulations. Thus, this work substantiated the fat-IBC signal transmission variability in the context of varying blood vessel configurations.

  • 2.
    Augustine, Robin
    Uppsala University.
    A Non-invasive Skin Burn Degree Analysis Using Microwaves2015Conference paper (Other academic)
  • 3.
    Augustine, Robin
    Uppsala University.
    Application of UWB Radar Techniques for Imaging cranial vaults2015Conference paper (Other academic)
  • 4.
    Augustine, Robin
    Uppsala University.
    Microwave head phantoms for post-craniotomy and BMP based implant2015Conference paper (Other academic)
  • 5.
    Augustine, Robin
    Uppsala University.
    Microwave studies on Beta Tricalcium Phosphate Bioceramics for medical application2006Conference paper (Refereed)
  • 6.
    Augustine, Robin
    Uppsala University.
    SRR Antenna for Biomedical Application2016Conference paper (Refereed)
  • 7.
    Bagge, Joakim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Farmakognosi.
    Chromatography of Therapeutic Peptides - Contrasting SFC and HPLC2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work is a comparison of a well-established and a novel, "green" and efficient technique to separate peptides of pharmaceutical interest. An attempt is made to derive the chromatographic retention behaviour from these techniques to a number of property descriptors derived from the linear sequence of amino acids. A set of therapeutic peptides were carefully chosen to be experimentally evaluated using in silico-based descriptor calculations. A principle component analysis was performed to assess the distribution of calculated descriptors for including peptides with variable properties. A diluent optimization study was also included to find the optimal diluent for peptides with minimal diluent effects and peak splitting phenomena. The results showed that the solvents tert-butanol and methanol performed best between 20-30 and 50 volumetric percent water as additive in SFC and HPLC, respectively. These diluents were then used for the peptides within the set to evaluate the retention and selectivity in HPLC and SFC. SFC performed well in terms of resolving power. Inparticular, SFC was able to separate Leuprolide and Triptorelin while HPLC was not. A comparison was also made in between the two stationary phases CN and XT, where a global selectivity was shown to be higher for CN.

    This work does also assess a novel method for determining solubility of analytes in supercritical fluid. The method was evaluated using the pharmaceutical compounds caffeine and aspirin and then used to determine solubility of Leu-Enkephalin in 20% (v/v%) methanol. The solubility of caffeine was determined to be 0.45 mg ml-1 in pure SF-CO2 under 140 bar pressure and 3.9 mg ml-1 for aspirin in 2.4% methanol. Both values correlated well with measurements from four acknowledged papers within this field. Leu-Enkephalin was found to have a solubility of 1.90 mg ml-1 using a solvent corresponding to the initial phase condition of the gradient used for peptide analysis in SFC. Further experimental work is required before the method can be implemented as a useful tool in preparative chromatography, however the results presented here show the compatibility of assessing biomolecules in both pure SF-CO2 and mixed with modifier. The possibility to determine solubility with additional modifier infers an important step of including and evaluating these compounds creating a solid support to subsequent large scale separation.

  • 8. Bjurman, Christian
    et al.
    Petzold, Max
    Venge, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Farbemo, Julia
    Fu, Michael L. X.
    Hammarsten, Ola
    High-sensitive cardiac troponin, NT-proBNP, hFABP and copeptin levels in relation to glomerular filtration rates and a medical record of cardiovascular disease2015In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 48, no 4-5, p. 302-307Article in journal (Refereed)
    Abstract [en]

    Background: Elevation of cardiac markers in patients with renal dysfunction has not been fully assessed reducing the diagnostic usefulness of these biomarkers. Objective: To examine the effects of renal function and a medical record of cardiovascular disease on levels of cardiac biomarkers. Methods: Serum samples were collected from 489 patients referred for GFR measurement using Cr51-EDTA or iohexol plasma clearance (measured GFR). The cardiac biomaiters Troponin T (hs-cTnT), Troponin I (hsTnI), N-Terminal pro Brain Natriuretic Peptide (NTproBNP), Copeptin, Human Fatty Acid Binding Protein (hFABP), as well as the kidney function biomarkers creatinine and cystatin C, were measured. Regression was used to analyse the relationship between biomarker levels and the glomerular filtration rate (GFR) between 15 and 90 mL/min/1.73 m(2). Results: Compared with normal kidney function, the estimated increases in the studied cardiac biomarkers at a CUR of 15 mL/mM/1.73 m(2) varied from 2-fold to 15 fold but were not very different between patients with or without a medical record of cardiovascular disease and were most prominent for cardiac biomarkers with low molecular weight. hs-cTnT levels correlated more strongly to measured CUR and increased more at low CUR compared to hs-cTnI. For hFABP and NT-proBNP increases at low kidney function were more correctly predicted by a local Cystatin C-based eGFR formula compared with creatinine-based eGFR (using the MDRD or CKD-EPI equations) Conclusion: The extent of the elevation of cardiac markers at low renal function is highly variable. For hFABP and NTproBNP Cystatin C-based eGFR provides better predictions of the extent of elevation compared to the MDRD or CKD-EPI equations. (C) 2015 The Authors. The Canadian Society of Clinical Chemists. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd,40/).

  • 9.
    Björkesten, Johan
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Molecular tools. Uppsala universitet.
    Dried blood sampling and digital readout to advance molecular diagnostics2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A drastically increased capacity to measure large sets of molecular features in numerous patient samples in great detail will be required to fulfill the vision of precision medicine and wellness, which may characterize molecular diagnostics in the 21st century. Also sampling procedures need a renaissance to permit continuous sampling at population levels at reasonable cost.

    Blood sampling is typically performed via venipuncture to draw several milliliters of blood for plasma isolation. This is inconvenient, time-consuming and costly, as well as hard to standardize. The effect on plasma protein profiles by pre-centrifugation delay was investigated in Paper II, demonstrating time- and temperature-dependent release of proteins from blood cells upon delayed plasma isolation, but almost no protein degradation as analyzed by two 92-plex protein panels (Olink® Proteomics). An alternative sampling method, where blood drops from a finger stick are collected dried on paper, is relatively non-invasive, potentially home-based and cheap. Dried blood spots can also be shipped via regular mail and compactly stored. The effect of drying and long term storage stability of a large set of proteins from dried blood spots was investigated in Paper I using Olink® technology. The main findings were that drying slightly but consistently influenced the recorded levels of blood proteins, and that long-term storage decreased the detected levels of some of the proteins with half-lives of decades.

    Some molecular diagnostic investigations require great accuracy to be useful, arguing for digital enumeration of individual molecules. Digital PCR is the gold standard but Paper III presents an alternative approach based on rolling circle amplification of single molecules. Another instance where extreme assay performance is required is for rare mutation detection from liquid biopsies. Paper V presents a new method offering essentially error-free genotyping of individual molecules by majority-vote decisions for counting rare mutant DNA in blood. Yet other diagnostic investigations require very simple assays. Paper IV presents a novel one-step method to detect nucleic acid sequences by combining the power of rolling circle amplification and the specificity of DNA strand displacement in a format simple enough to be used at the point of care.   

    Altogether, the thesis spans technologies for advanced molecular diagnostics, from sample collection over assay techniques to an improved readout.

    List of papers
    1. Stability of Proteins in Dried Blood Spot Biobanks.
    Open this publication in new window or tab >>Stability of Proteins in Dried Blood Spot Biobanks.
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    2017 (English)In: Molecular & Cellular Proteomics, ISSN 1535-9476, E-ISSN 1535-9484, Vol. 16, no 7, p. 1286-1296Article in journal (Refereed) Published
    Abstract [en]

    An important motivation for the construction of biobanks is to discover biomarkers that identify diseases at early, potentially curable stages. This will require biobanks from large numbers of individuals, preferably sampled repeatedly, where the samples are collected and stored under conditions that preserve potential biomarkers. Dried blood samples are attractive for biobanking because of the ease and low cost of collection and storage. Here we have investigated their suitability for protein measurements. 92 proteins with relevance for oncology were analyzed using multiplex proximity extension assays (PEA) in dried blood spots collected on paper and stored for up to 30 years at either +4&deg;C or -24&deg;C.</p> <p>Our main findings were that 1) the act of drying only slightly influenced detection of blood proteins (average correlation of 0.970), and in a reproducible manner (correlation of 0.999), 2) detection of some proteins was not significantly affected by storage over the full range of three decades (34% and 76% of the analyzed proteins at +4&deg;C and -24&deg;C, respectively), while levels of others decreased slowly during storage with half-lives in the range of 10 to 50 years, and 3) detectability of proteins was less affected in dried samples stored at -24&deg;C compared to at +4&deg;C, as the median protein abundance had decreased to 80% and 93% of starting levels after 10 years of storage at +4&deg;C or -24&deg;C, respectively. The results of our study are encouraging as they suggest an inexpensive means to collect large numbers of blood samples, even by the donors themselves, and to transport, and store biobanked samples as spots of whole blood dried on paper. Combined with emerging means to measure hundreds or thousands of protein, such biobanks could prove of great medical value by greatly enhancing discovery as well as routine analysis of blood biomarkers.

    Keywords
    Absolute quantification, Affinity proteomics, Biobanking, Bioinformatics splicing, Biomarkers, Blood*, DBS, Diagnostic, Dried Blood Spot, Multiplex protein detection, PCR, Plasma or serum analysis, Predictive markers*, Protein Stability, Proximity Extension Assay
    National Category
    Clinical Laboratory Medicine
    Identifiers
    urn:nbn:se:uu:diva-322568 (URN)10.1074/mcp.RA117.000015 (DOI)000404597500009 ()28501802 (PubMedID)
    Funder
    Swedish Research CouncilEU, FP7, Seventh Framework Programme, 294409Novo Nordisk
    Available from: 2017-05-25 Created: 2017-05-25 Last updated: 2019-11-03Bibliographically approved
    2. Strong impact on plasma protein profiles by precentrifugation delay but not by repeated freeze-thaw cycles, as analyzed using multiplex proximity extension assays
    Open this publication in new window or tab >>Strong impact on plasma protein profiles by precentrifugation delay but not by repeated freeze-thaw cycles, as analyzed using multiplex proximity extension assays
    Show others...
    2018 (English)In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 56, no 4, p. 582-594Article in journal (Refereed) Published
    Abstract [en]

    Background: A number of factors regarding blood collection, handling and storage may affect sample quality. The purpose of this study was to assess the impact on plasma protein profiles by delayed centrifugation and plasma separation and multiple freeze-thaw cycles.

    Methods: Blood samples drawn from 16 healthy individuals were collected into ethylenediaminetetraacetic acid tubes and kept either at 4 degrees C or 22 degrees C for 1-36 h prior to centrifugation. Plasma samples prepared 1 h after venipuncture were also subjected to two to eight cycles of freezing at -80 degrees C and thawing at 22 degrees C. Multiplex proximity extension assay, an antibody-based protein assay, was used to investigate the influence on plasma proteins.

    Results: Up to 36 h delay before blood centrifugation resulted in significant increases of 16 and 40 out of 139 detectable proteins in samples kept at 4 degrees C or 22 degrees C, respectively. Some increases became noticeable after 8 h delay at 4 degrees C but already after 1 h at 22 degrees C. For samples stored at 4 degrees C, epidermal growth factor (EGF), NF-kappa-B essential modulator, SRC, interleukin 16 and CD6 increased the most, whereas the five most significantly increased proteins after storage at 22 degrees C were CD40 antigen ligand (CD40-L), EGF, platelet-derived growth factor subunit B, C-X-C motif chemokine ligand 5 and matrix metallopeptidase 1 (MMP1). Only matrix metallopeptidase 7 (MMP7) decreased significantly over time and only after storage at 22 degrees C. No protein levels were found to be significantly affected by up to eight freeze-thaw cycles.

    Conclusions: Plasma should be prepared from blood after a limited precentrifugation delay at a refrigerated temperature. By contrast, the influence by several freeze-thaw cycles on detectable protein levels in plasma was negligible.

    Place, publisher, year, edition, pages
    WALTER DE GRUYTER GMBH, 2018
    Keywords
    biobank, protein detection, proteome, proximity extension assay (PEA), sample collection and handling
    National Category
    Clinical Laboratory Medicine
    Identifiers
    urn:nbn:se:uu:diva-350276 (URN)10.1515/cclm-2017-0648 (DOI)000426657400016 ()29040064 (PubMedID)
    Funder
    Swedish Research Council, 829-2009-6285EU, European Research Council, 313010, 294409
    Available from: 2018-05-14 Created: 2018-05-14 Last updated: 2019-11-03Bibliographically approved
    3. Multiplex digital enumeration of circular DNA molecules on solid supports
    Open this publication in new window or tab >>Multiplex digital enumeration of circular DNA molecules on solid supports
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Digital PCR is a detection method with unprecedented accuracy for DNA quantification, but with some limitations in the form of complexity of instrumentation and limited multiplexing. Here we present an isothermal platform for digital enumeration of DNA reaction products in multiplex via standard fluorescence microscopy, to overcome limitations of digital PCR. In this method, sets of small DNA circles, resulting from detection reactions, are captured on a streptavidin-coated surface and subjected to rolling circle amplification (RCA). We found that the addition of 15% polyethylene glycol 4000 to RCA on planar surfaces ensured uniform, easily counted signals, each of which represents an individual reaction product. The DNA circles were immobilized and detected with efficiencies of 50 and 100%, respectively, as determined by droplet digital PCR. We confirmed previous reports about the effect on RCA efficiency by sequence composition and size of the RCA templates at the level of individual amplified molecules, and we developed an efficient one-step de- and re-staining procedure for sequential multiplexing via toehold-triggered DNA strand displacement.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-396324 (URN)
    Available from: 2019-11-03 Created: 2019-11-03 Last updated: 2019-11-03
    4. Rolling circle amplification reporters – a general tool to simplify molecular detections
    Open this publication in new window or tab >>Rolling circle amplification reporters – a general tool to simplify molecular detections
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Methods to detect biomolecules via rolling circle amplification (RCA), for example padlock probes and proximity ligation assay (PLA) tend to be complex and include several reaction steps. Herein, we evaluated a new tool for the toolbox of RCA-based detection methods - RCA Reporters. Briefly, RCA Reporters represent inert DNA structures that, upon contact with a specific nucleic acid sequence, unravel via a highly specific strand displacement process to initiate local enzyme-assisted RCA reactions. The RCA Reporters can be used to directly detect ssDNA or RNA in a sample, or proteins via oligonucleotide-conjugated antibodies. The reagents can also enable faster RCA reactions or extremely selective genotyping of RCA products with repeated copies of a target sequence through a majority-vote mechanism. Further amplification of ongoing RCA reactions via RCA Reporters can allow efficient digital enumeration of single molecules via flow cytometry, with potential for simple and highly accurate molecular counting assays. The intrinsic simplicity of RCA Reporter also renders them attractive for applications at the point of care.

    National Category
    Genetics
    Identifiers
    urn:nbn:se:uu:diva-331743 (URN)
    Available from: 2017-10-17 Created: 2017-10-17 Last updated: 2019-11-03
    5. Rare Mutation Detection in Blood Plasma Using sRCA Molecule Counting Probes
    Open this publication in new window or tab >>Rare Mutation Detection in Blood Plasma Using sRCA Molecule Counting Probes
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Problems in biology and medicine frequently require the ability to observe, evaluate, andcount even extremely rare macromolecules in biological samples. In particular, rare tumorspecific mutations in plasma provide valuable insights in the course of malignant disease andresponses to therapy, but simpler assay techniques are needed. We describe herein a rapidand exquisitely specific means to recognize and magnify detection signals from individualmolecules to easily recorded levels via a process we call super rolling circle amplification(sRCA). We demonstrate the ability of this technique to enumerate tumor-specific sequencevariants in plasma from cancer patients via flow cytometry at very high efficiency, with specificityadequate to detect single nucleotide mutant sequences among 100,000 copies of thenormal sequence in a 3 hr protocol. And the mutation analysis data generated from patientctDNA samples with our sRCA method are in high accordance with the patients’ primary tumorsequencing data.

    Keywords
    Rolling circle amplification, cfDNA, single molecule, digital counting, rare mutation detection, PoC application
    National Category
    Genetics
    Identifiers
    urn:nbn:se:uu:diva-331737 (URN)
    Available from: 2017-10-17 Created: 2017-10-17 Last updated: 2019-11-03
  • 10.
    Bäckryd, Emmanuel
    et al.
    Linköping University, Linköping, Sweden.
    Lind, Anne-Li
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Thulin, Måns
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Statistics.
    Larsson, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Gerdle, Björn
    Linköping University, Linköping, Sweden.
    Gordh, Torsten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    High Levels of Cerebrospinal Fluid Chemokines Point to the Presence of Neuroinflammation in Peripheral Neuropathic Pain: A Cross-Sectional Study of Two Cohorts of Patients Compared to Healthy ControlsManuscript (preprint) (Other academic)
    Abstract [en]

    Animal models suggest that chemokines are important mediators in the pathophysiology of neuropathic pain. Indeed, these substances have been called “gliotransmitters”, a term that illustrates the close interplay between glial cells and neurons in the context of neuroinflammation and pain. However, evidence in humans is scarce. The aim of the study was to determine a comprehensive cerebrospinal fluid (CSF) inflammatory profile for neuropathic pain patients. Our hypothesis was that we would thereby find indications of a postulated on-going process of central neuroinflammation.  

    CSF samples were collected from two cohorts of patients with neuropathic pain (n=11 and n=16, respectively) and healthy controls (n=11). The samples were analyzed with a multiplex proximity extension assay in which 92 inflammation-related proteins were measured simultaneously (Proseek® Multiplex Inflammation I, Olink Bioscience, Uppsala, Sweden). Univariate testing with control of false discovery rate, as well as orthogonal partial least squares – discriminant analysis, were used for statistical analyses.

    CSF levels of chemokines CXCL6, CXCL10, CCL8, CCL11, CCL23, as well as protein LAPTGF-beta-1, were significantly higher in both neuropathic pain cohorts compared to healthy controls, pointing to neuroinflammation in patients. These 6 proteins were also major results in a recent similar study in fibromyalgia patients. The findings need to be confirmed in larger cohorts, and the question of causality remains to be settled. Since it has been suggested that prevalent co-morbidities to chronic pain (e.g., depression, anxiety, poor sleep, and tiredness) also are associated with inflammation, it will be important to determine whether inflammation is a common mediator.

  • 11.
    Cai, Bing
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Söderkvist, Karin
    Dept of Analytical Chemistry, Orexo AB, Uppsala.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Bredenberg, Susanne
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    A New Drug Release Method in Early Development of Transdermal Drug Delivery Systems2012In: Pain Research and Treatment, ISSN 2090-1542, Vol. 2012, p. 953140-Article in journal (Refereed)
    Abstract [en]

    In vitro drug release tests are a widely used tool to measure the variance between transdermal product performances and required by many authorities. However, the result cannot provide a good estimation of the in vivo drug release.  In the present work, a new method for measuring drug release from patches has been explored and compared with the conventional USP apparatus 2 and 5 methods. Durogesic patches, here used as a model patch, were placed on synthetic skin simulator and three moisture levels (29, 57, 198 μL cm−2) were evaluated. The synthetic skin simulators were collected after 1, 2, 3, 4, 6, and 24 hours and extracted with pH 1.0 hydrochloric acid solution. The drug concentrations in the extractions were measured by isocratic reverse phase high-pressure liquid chromatography. The results showed that, with the increasing moisture level on the synthetic skin simulator, the drug release rate increased. In comparison with the conventional USP method, the drug release results performed by the new method were in more correlation to the release rate claimed in the product label. This new method could help to differentiate the drug release rates among assorted formulations of transdermal drug delivery systems in the early stage of development.

  • 12.
    Cubo, Rubén
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Medvedev, Alexander
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Individualization of a surrounding tissue model in Deep Brain Stimulation2017In: Proc. 56th Conference on Decision and Control, Piscataway, NJ: IEEE, 2017, p. 5919-5924Conference paper (Refereed)
  • 13. Durán-Acevedo, Cristhian Manuel
    et al.
    Jaimes-Mogollón, Aylen Lisset
    Gualdrón-Guerrero, Oscar Eduardo
    Welearegay, Tesfalem Geremariam
    Martinez-Marín, Julián Davíd
    Caceres-Tarazona, Juan Martín
    Sánchez-Acevedo, Zayda Constanza
    Beleño-Saenz, Kelvin de Jesus
    Cindemir, Umut
    Österlund, Lars
    Ionescu, Radu
    Exhaled breath analysis for gastric cancer diagnosis in Colombian patients.2018In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 9, no 48, p. 28805-28817Article in journal (Refereed)
    Abstract [en]

    We present here the first study that directly correlates gastric cancer (GC) with specific biomarkers in the exhaled breath composition on a South American population, which registers one of the highest global incidence rates of gastric affections. Moreover, we demonstrate a novel solid state sensor that predicts correct GC diagnosis with 97% accuracy. Alveolar breath samples of 30 volunteers (patients diagnosed with gastric cancer and a controls group formed of patients diagnosed with other gastric diseases) were collected and analyzed by gas-chromatography/mass-spectrometry (GC-MS) and with an innovative chemical gas sensor based on gold nanoparticles (AuNP) functionalized with octadecylamine ligands. Our GC-MS analyses identified 6 volatile organic compounds that showed statistically significant differences between the cancer patients and the controls group. These compounds were different from those identified in previous studied performed on other populations with high incidence rates of this malady, such as China (representative for Eastern Asia region) and Latvia (representative for Baltic States), attributable to lifestyle, alimentation and genetics differences. A classification model based on principal component analysis of our sensor data responses to the breath samples yielded 97% accuracy, 100% sensitivity and 93% specificity. Our results suggest a new and non-intrusive methodology for early diagnosis of gastric cancer that may be deployed in regions lacking well-developed health care systems as a prediagnosis test for selecting the patients that should undergo deeper investigations (e.g., endoscopy and biopsy).

  • 14.
    Eggers, Kai M.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Serial Measurement of Biomarkers after Acute Coronary Syndrome: Which One to Choose?2017In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 63, no 7, p. 1181-1183Article in journal (Other academic)
  • 15.
    Eggers, Kai M.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Johnston, Nina
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Lind, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiovascular epidemiology.
    Venge, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Cardiac troponin I levels in an elderly population from the community - The implications of sex2015In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 48, no 12, p. 751-756Article in journal (Refereed)
    Abstract [en]

    Objectives: The importance of sex on cardiac troponin levels is increasingly recognized. We investigated whether the entities associated with troponin leakage and the prognostic consequences thereof would differ between elderly men and women from the community. Design and methods: Cardiac troponin I (cTnI) levels were measured using a high-sensitivity assay (Abbott Laboratories) in 70-year old men (n = 502) and women (n = 502) from the PIVUS study. All study participants were followed up for 10 years regarding all-cause mortality and incident cardiovascular (CV) disease. Results: Median cTnI levels were 4.1 and 3.0 ng/L in men and women, respectively (p < 0.001). By multiple linear regression, the relative contribution of lower left-ventricular ejection fraction and ischemic ECG changes to cTnI levels was greater in men compared to women. For other clinical and echocardiographic variables, similar associations were found. cTnI independently predicted all-cause mortality in men (n = 93 [18.5%]; hazard ratio [HR] 1.38 [1.12-1.70]) and women (n = 62 [12.4%]; HR 1.59 [1.11-2.28]) but not incident CV disease in subjects being CV healthy at baseline (n = 163/857). The interaction terms of sex on the associations of cTnI with both outcomes were non-significant. Sex-specific cut-offs did not improve prognostication. Variations in the pattern of entities associated with cTnI leakage had no impact on event rates. Conclusions: We found some differences in the entities associated with higher cTnI levels in elderly community-dwelling men and women. However, this did not translate into differences in the associations of cTnI with adverse outcome.

  • 16.
    Elofsson, Hampus
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Immunoassay engineering: An explorative comparison of detection chemestries and surfaces for protein microarrays2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 17.
    Encarnação, João Crispim
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Medical Radiation Science. Department of Immunology, Genetics and Pathology.
    Towards time-resolved molecular interaction assays in living bacteria2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rare and neglected diseases such as multidrug resistant (MDR) tuberculosis, malaria and trypanosomiasis are re-emerging in Europe. New strategies are needed to accelerate drug discovery to fight these pathogens. AEGIS is a Pan-European project that combines different technologies to accelerate the discovery of molecules suitable for drug development in selected neglected diseases. This thesis is part of the AEGIS research area that considers time in a multidisciplinary approach, combining biology, physics and mathematics to provide tools to characterize biological events for improving drug development and information about the target diseases and lead compounds.

    Real-time cell binding assays (RT-CBA) of receptor-ligand interactions are fundamental in basic research and drug discovery. However, this kind of assays are still rare on living cells, especially in the microbiology field. In this project, we apply the same high-precision assay type on bacterial systems and explored the interior of the cell with a time resolved assay.

    The effect of temperature was evaluated in the RT-CBA using LigandTracer to ensure that it was possible to use the technology in a range of temperatures suitable for bacteria. A method for attaching Gram positive and negative bacteria on the surface of a normal Petri dish, showing a high reproducibly and a high cellular viability after 16 h. With these two key steps, an RT-CBA fit for microbiology is available.

    Next, to answer biological questions, intracellular interactions were explored by expression and validation of intracellular proteins with fluorescent tags suitable for RT-CBAs. First, we used the subunit B from the Shiga toxin (STxB) as a model to understand different aspects about the internalization processes. RT-CBAs allowed to discovery new features of STxB binding and mechanism to deliver small molecules or small proteins into cancer cells. Then, for exploring intracellular interactions, insect cells were bioengineered for evaluating the ability of small molecules to internalize and bind to its target. Using Carbonic anhydrase II – sulfonamides as a model system, the molecular interaction in the cytoplasm could be measured using a quencher label approach. The development of this kind of novel RT-CBA tools provide new information about drug candidates for targets that are not properly expressed in bacterial cells.

    The assays in this project can make drug design more efficient. Furthermore, the evaluation of binding activity of the new compounds developed by AEGIS, focusing on rare/neglected diseases, in a biological environment has the potential to accelerate drug discovery for the targeted emerging diseases.

    List of papers
    1. Impact of assay temperature on antibody binding characteristics in living cells: A case study
    Open this publication in new window or tab >>Impact of assay temperature on antibody binding characteristics in living cells: A case study
    2017 (English)In: BIOMEDICAL REPORTS, ISSN 2049-9434, Vol. 7, no 5, p. 400-406Article in journal (Refereed) Published
    Abstract [en]

    Kinetic and thermodynamic studies of ligand-receptor interactions are essential for increasing the understanding of receptor activation mechanisms and drug behavior. The characterization of molecular interactions on living cells in real-time goes beyond most current binding assays, and provides valuable information about the dynamics and underlying mechanism of the molecules in a living system. The effect of temperature on interactions in cell-based assays is, however, rarely discussed. In the present study, the effect of temperature on binding of monoclonal antibodies, cetuximab and pertuzumab to specific receptors on living cancer cells was evaluated, and the affinity and kinetics of the interactions were estimated at selected key temperatures. Changes in the behavior of the interactions, particularly in the on- and off-rates were observed, leading to greatly extended time to reach the equilibrium at 21 degrees C compared with at 37 degrees C. However, the observed changes in kinetic characteristics were less than a factor of 10. It was concluded that it is possible to conduct real-time measurements with living cells at different temperatures, and demonstrated that influences of the ambient temperature on the interaction behavior are likely to be less than one order of magnitude.

    Keywords
    drug kinetics, thermodynamics, real-time interactions, clinical monoclonal antibodies, growth factor receptors
    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:uu:diva-345264 (URN)10.3892/br.2017.982 (DOI)000417416000002 ()29181152 (PubMedID)
    Funder
    EU, Horizon 2020, 2014-2020
    Available from: 2018-03-09 Created: 2018-03-09 Last updated: 2019-11-22Bibliographically approved
    2. Detecting ligand interactions in real time on living bacterial cells
    Open this publication in new window or tab >>Detecting ligand interactions in real time on living bacterial cells
    Show others...
    2018 (English)In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 102, no 9, p. 4193-4201Article in journal (Refereed) Published
    Abstract [en]

    Time-resolved analysis assays of receptor-ligand interactions are fundamental in basic research and drug discovery. Adequate methods are well developed for the analysis of recombinant proteins such as antibody-antigen interactions. However, assays for time-resolved ligand-binding processes on living cells are still rare, in particular within microbiology. In this report, the real-time cell-binding assay (RT-CBA) technology LigandTracerA (R), originally designed for mammalian cell culture, was extended to cover Gram-positive and Gram-negative bacteria. This required the development of new immobilization methods for bacteria, since LigandTracer depends on cells being firmly attached to a Petri dish. The evaluated Escherichia coli CJ236 and BL21 as well as Staphylococcus carnosus TM300 strains were immobilized to plastic Petri dishes using antibody capture, allowing us to depict kinetic binding traces of fluorescently labeled antibodies directed against surface-displayed bacterial proteins for as long as 10-15 h. Interaction parameters, such as the affinity and kinetic constants, could be estimated with high precision (coefficient of variation 9-44%) and the bacteria stayed viable for at least 16 h. The other tested attachment protocols were inferior to the antibody capture approach. Our attachment protocol is generic and could potentially also be applied to other assays and purposes.

    Place, publisher, year, edition, pages
    SPRINGER, 2018
    Keywords
    Real-time interactions, Drug kinetics, Living bacteria, Antibodies
    National Category
    Biochemistry and Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-352571 (URN)10.1007/s00253-018-8919-3 (DOI)000429800600027 ()29550990 (PubMedID)
    Funder
    Swedish Research CouncilEU, European Research Council, 675555
    Available from: 2018-08-07 Created: 2018-08-07 Last updated: 2019-11-22Bibliographically approved
    3. Revealing the dynamic features of STxB-Gb3 co-internalization mechanism of molecular cargo into cancer cells
    Open this publication in new window or tab >>Revealing the dynamic features of STxB-Gb3 co-internalization mechanism of molecular cargo into cancer cells
    (English)Manuscript (preprint) (Other academic)
    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:uu:diva-397748 (URN)
    Available from: 2019-11-25 Created: 2019-11-25 Last updated: 2019-12-02
    4. Bioengineering living cells for measuring intracellular interactions of small-molecules in real-time
    Open this publication in new window or tab >>Bioengineering living cells for measuring intracellular interactions of small-molecules in real-time
    (English)Manuscript (preprint) (Other academic)
    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:uu:diva-397752 (URN)
    Available from: 2019-11-25 Created: 2019-11-25 Last updated: 2019-12-02
  • 18.
    Engelmark, Malin T.
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Beskow, Anna H.
    Analysis of the Research Sample Collections of Uppsala Biobank2014In: Biopreservation and Biobanking, ISSN 1947-5535, E-ISSN 1947-5543, Vol. 12, no 5, p. 325-331Article in journal (Refereed)
    Abstract [en]

    Uppsala Biobank is the joint and only biobank organization of the two principals, Uppsala University and Uppsala University Hospital. Biobanks are required to have updated registries on sample collection composition and management in order to fulfill legal regulations. We report here the results from the first comprehensive and overall analysis of the 131 research sample collections organized in the biobank. The results show that the median of the number of samples in the collections was 700 and that the number of samples varied from less than 500 to over one million. Blood samples, such as whole blood, serum, and plasma, were included in the vast majority, 84.0%, of the research sample collections. Also, as much as 95.5% of the newly collected samples within healthcare included blood samples, which further supports the concept that blood samples have fundamental importance for medical research. Tissue samples were also commonly used and occurred in 39.7% of the research sample collections, often combined with other types of samples. In total, 96.9% of the 131 sample collections included samples collected for healthcare, showing the importance of healthcare as a research infrastructure. Of the collections that had accessed existing samples from healthcare, as much as 96.3% included tissue samples from the Department of Pathology, which shows the importance of pathology samples as a resource for medical research. Analysis of different research areas shows that the most common of known public health diseases are covered. Collections that had generated the most publications, up to over 300, contained a large number of samples collected systematically and repeatedly over many years. More knowledge about existing biobank materials, together with public registries on sample collections, will support research collaborations, improve transparency, and bring us closer to the goals of biobanks, which is to save and prolong human lives and improve health and quality of life.

  • 19.
    Eriksson, Mats B
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Strandberg, Gunnar
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Lipcsey, Miklós
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Larsson, Anders
    inst för medicinska vetenskaper.
    Troponin I can be Determined in Intraosseous Aspirates in a Porcine Shock Model2015In: Clinical Laboratory, ISSN 1433-6510, Vol. 61, no 7, p. 825-829Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Determination of troponin I may be important in the management of the critically ill patient. In medical emergencies, especially when vascular access is difficult to achieve, the use of intraosseous (10) needles is recommended. We aimed to perform a descriptive study, aiming to elucidate whether IO needles can be used to evaluate troponin I in a porcine model of human shock.

    METHODS: Eight pigs were anesthetized and challenged with a 6 hours continuous intravenous infusion of E. coli endotoxin. An IO needle (EZ-IO®) was inserted in the proximal tibia of each pig. Circulatory variables were monitored and troponin I was sampled from arterial and venous blood and also from bone marrow aspirates.

    RESULTS: Circulatory deterioration developed in all endotoxemic animals, which was reflected by a profound deterioration of left ventricular stroke work index. Troponin I levels were nearly identical in both arterial, venous, and IO samples during the first hour of endotoxemia. At 1 hour, all mean troponin I levels had more than doubled as compared to baseline. The troponin I levels continued to increase over time and were markedly elevated versus baseline levels during the 2nd and 6th hours, regardless of sampling site. At 3 hours, IO troponin I reached a plateau, whereas troponin I in both arterial and venous blood continued to increase.

    CONCLUSIONS: This investigation has shown that troponin I can be analyzed in bone marrow aspirates in a shock model. This may be useful in medical emergencies, where cardiac damage is suspected to be involved. The levels of IO troponin I increased during the first 3 hours of shock, after which it remained at a high level. During this initial period there was, in parallel, a progressive circulatory deterioration.

  • 20.
    Fornell, Anna
    et al.
    Department of Biomedical Engineering, Lund University, Sweden.
    Cushing, Kevin
    Department of Biomedical Engineering, Lund University, Lund, Sweden.
    Nilsson, Johan
    Department of Biomedical Engineering, Lund University, Lund, Sweden.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Intra-droplet acoustic separation of two particle species in a droplet microfluidic system2017Conference paper (Refereed)
  • 21.
    Fornell, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Liu, Zhenhua
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Improved acoustic particle enrichment in droplets by optimising the droplet split design2019Conference paper (Other academic)
    Abstract [en]

    Droplet microfluidics has emerged as a valuable platform for miniaturisation of biological experiments on-chip. In droplet microfluidic chips monodisperse droplets containing cells or other bioparticles can be generated at high throughput, and each droplet can be used as an isolated reaction chamber for individual measurements. A general trend in droplet microfluidics is reducing the size of the droplets, but the challenge is maintaining the particles in the droplets after splitting. We have previously reported on an acoustofluidic chip where bulk acoustic waves were used to control particle positioning in a trident-shaped droplet split. However, the reported particle enrichment was modest (3-fold), and the aim of this study is to increase the particle enrichment by optimising the droplet split design. With our new optimised droplet split we show up to 16.7-fold particle enrichment with high particle recovery.

  • 22.
    Fornell, Anna
    et al.
    Department of Biomedical Engineering, Lund University, Sweden.
    Ohlin, Mathias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Nilsson, Johan
    Department Biomedical Engineering, Lund University.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    A droplet unit operator for controlled particle switching and enrichment2017Conference paper (Refereed)
  • 23.
    Fornell, Anna
    et al.
    Department of Biomedical Engineering, Lund University, Sweden.
    Ohlin, Mathias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Nilsson, Johan
    Department of Biomedical Engineering, Lund University, Sweden.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    An optimized droplet split designed for acoustic intra-droplet particle enrichment2017Conference paper (Refereed)
  • 24.
    Hedlund, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology.
    Tyst kunskap och produktdatasystem vid medicinteknisk tillverkning: Pilotstudie av system för produktdatahantering och kartläggning av den tysta kunskapen vid Nationellt respirationscetrum, NRC2009Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis looks at two sides of the same coin: how to support the production and future development at a specialist medical technology department at Danderyd Hospital. The two sides are; a pilot study of a product management system (PDM) and an interview based study on the characteristics of the silent knowledge of the technicians. The department (National respiratory centre, NRC) is facing retirement of several key employees.

    The technical study shows that the success of an implementation is largely dependent on the users’ prior knowledge and use of a 3D Computer aided design system (CAD).The system itself is shown to fulfill the Lifecycle requirement of tracking the products (mostly tracheostomy tubes) but without a CAD centered workflow, some substantial education and preferably some new recruits, an implementation of the PDM system will fail. The author recommends development of the current “low-tech” system of MS Excel and Access rather than redistribute the dependency from technician towards a complex, commercial software and its vendor.

    The analysis of the technicians’ silent knowledge with the newly developed method, epithet for silent knowledge (ETK), shows that the longer employment time:

    • the more differentiated technicians become in describing their work,
    • practical knowledge are regarded higher and
    • the social and collective problem solving factors of the work becomes more important.

    Typically, it is shown that a new employee should preferably enjoy problem solving, being pragmatic and social as well as having some prior education or work experience in a CAD and/or a PDM system.

  • 25. Hickman, Peter E.
    et al.
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Potter, Julia M.
    Venge, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Koerbin, Gus
    Eggers, Kai M.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Is It Time to Do Away With the 99th Percentile for Cardiac Troponin in the Diagnosis of Acute Coronary Syndrome and the Assessment of Cardiac Risk?2014In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 60, no 5, p. 734-736Article in journal (Other academic)
  • 26.
    Johansson, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Microscale measurement of kinetic binding properties of monoclonal antibodies in solution using Gyrolab2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The number of monoclonal antibodies approved for therapeutic use has increased rapidlyover the last decade. As a consequence, precise and robust kinetic characterization techniquesare crucial in order to select the best suitable candidates. A kinetic characterization methodwas developed in Gyrolab with automated sample transfers. The characterization wasperformed in solution in a mixing CD, containing an integrated nanoliter mixing chamberwith affinity binding columns. Association rate constants were determined for four anti-TSHantibodies with values ranging from 3x105 M-1s-1 to 10x105 M-1s-1. The antibodies wereranked according to kass. Reproducibility

  • 27.
    Kühnemund, Malte
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology. Science for life laboratory.
    Wei, Qingshan
    Department of Bioengineering, University of California Los Angeles (UCLA).
    Darai, Eva
    Science for life laboratory, Stockholm University.
    Wang, Y
    Department of Bioengineering, University of California Los Angeles (UCLA).
    Hernandez-Neuta, Ivan
    Science for life laboratory, Stockholm University.
    Tseng, D
    Department of Bioengineering, University of California Los Angeles (UCLA).
    Ahlford, Annika
    Science for life laboratory, Stockholm University.
    Ozcan, Aydogan
    Department of Bioengineering, University of California Los Angeles (UCLA).
    Nilsson, Mats
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology. Science for life laboratory, Stockholm University.
    In situ detection of KRAS point mutations and targeted DNA sequencing with a mobile phoneManuscript (preprint) (Other academic)
  • 28.
    Lagmo, Johan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine.
    Development of a multiplex real time PCR assay to target bacteria causing meningitis2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 29.
    Liu, Zhenhua
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Fornell, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    A continuous on-chip droplet washing platform with high bead recovery by acoustofluidics2019Conference paper (Other academic)
    Abstract [en]

    Acoustofluidics is a promising technology for manipulation of fluids and particles in microchannels, and the technology has the ability to sort beads and cells in continuous flow with very high efficiency. Recently acoustofluidics has also been applied in segmental flow for positioning beads inside droplets. Compared with single-phase systems, droplet microfluidics has the advantages of faster reactions, lower cross-contamination and higher throughput. Moreover, the small size of the droplets makes them ideal as cultivation and reaction vials for single cell analysis. However, as the droplets are so small one challenge is to wash the droplets before image analysis. P. Mary et al. developed a microfluidic platform for droplet wash, whichis based on electrocoalescence and droplet break-ups with equal volume. The background noise was decreased significantly, however the recovery of the encapsulated cells was low. Alternative solutions have been presented by H. Lee et al. and S.R. Doonan et al. but as the bead recovery is controlled via magnetophoresis, the technology is only applicable to magnetic samples. Here we present a droplet microfluidic platform that enables background dilution with high bead recovery in a label-free manner using acoustophoresis.

  • 30.
    Ohlin, Mathias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Andersson, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Klintberg, Lena
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    In situ temperature monitoring during acoustophoresis using integrated thin film Pt temperature sensors2017Conference paper (Refereed)
  • 31.
    Ohlin, Mathias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Andersson, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Klintberg, Lena
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Internal temperature sensing in an acoustophoretic glass chip2017Conference paper (Refereed)
  • 32.
    Persson, Cecilia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    López, Alejandro
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Unosson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Customised Bone Cement for Vertebroplasty2010In: Interfacing biology and materials, 2010Conference paper (Refereed)
  • 33.
    Raman, Sujith
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Augustine, Robin
    Uppsala University.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Osseointegration analysis of skull implants using microstrip fed split ring resonator antenna2014In: 2014 XXXITH URSI General Assembly And Scientific Symposium (URSI GASS), 2014Conference paper (Refereed)
    Abstract [en]

    A microwave technique for skull implant curing analysis is presented here. A microstrip antenna is used for osseointegration analysis with respect to the dielectric profile variation of the implant. The bone and implant gives a high degree of discrimination in resonant frequency of reflection coefficient. The prototype is designed to retain the impedance matching at all implant conditions and even in normal phantom. The antennas simulated on three different substrates layers are fabricated and concept is experimentally verified with phantom models.

  • 34.
    Rasmussen, Ib Christian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Upper Abdominal Surgery.
    Measurements of blood flow in animal research1998In: Animal Modelling in Surgical Research / [ed] Bengt Jeppsson, Harwood Academic, 1998Chapter in book (Other academic)
  • 35.
    Ridefelt, Peter
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Pediatric reference intervals - The Swedish experience2014In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 47, no 9, p. 740-741Article in journal (Refereed)
  • 36.
    Ridefelt, Peter
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Åkerfeldt, Torbjörn
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemical endocrinology.
    Helmersson-Karlqvist, Johanna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Increased plasma glucose levels after change of recommendation from NaF to citrate blood collection tubes2014In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 47, no 7-8, p. 625-628Article in journal (Refereed)
    Abstract [en]

    Objectives: To evaluate changes in plasma glucose measurements in an unselected patient population after a change of recommendation from NaF to citrate blood collection vacuum tubes. Design and methods: Glucose (n = 460 751) and HbA1c (n = 55 190) determinations during a period of approximately three years before and after the tube change were extracted from a laboratory information system. Results: Median values for plasma glucose determinations increased from 6.03 before to 6.28 mmol/L after the tube change. The proportion of glucose determinations above the WHO limit for impaired fasting glucose (6.1 mmol/L) and the medical decision limit for diabetes (7.0 mmol/L) increased from 48.1 to 55.4% after the change. Conclusions: The change from NaF to citrate tubes caused higher glucose values, and consequently more glucose determinations above the decision limit for diabetes.

  • 37. Savukoski, Tanja
    et al.
    Mehtala, Laura
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center.
    Venge, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Biochemial structure and function.
    Pettersson, Kim
    Elevation of cardiac troponins measured after recreational resistance training2015In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 48, no 12, p. 803-806Article in journal (Refereed)
    Abstract [en]

    Background: Whereas elevated cardiac troponin (cTn) concentrations i.e. above the 99th percentile of healthy reference population (recommended cutoff for the diagnosis of myocardial infarction) are well-documented in healthy individuals after prolonged and/or intensive exercises such as marathons, data on less-strenuous sports are scarce. Therefore, our aim was to investigate cTnI and cTnT release in response to recreational resistance training, here a single-bout of 1-h kettlebell workout. Methods: Serum samples were collected from 11 apparently healthy volunteers the previous day (pre-exercise), three hours after the kettlebell class (post-exercise), the next day and three days later. The aliquoted samples were analyzed with Abbott Laboratories' Architect high-sensitivity (hs)-cTnI assay (limit of detection, LoD = 2 ng/L), our 3 + 1-type cTnI assay free from cTn-specific autoantibody interference (LoD = 3 ng/L) and Roche Diagnostics' hs-cTnT assay CLOD = 5 ng/L). Results: The post-exercise cTn concentrations were significantly higher than the pre-exercise values (median 5.5-9.6 ng/L vs. <LoD, P < 0.05 for all) and they correlated strongly between the three assays (Spearman r = 0.881-0.960, P < 0.001 for all). Furthermore, a few post-exercise concentrations even exceeded the 99th percentile of Architect hs-cTnI (>26 ng/L, n = 2) and/or hs-cTnT (>14 ng/L, n = 4). The cTn concentrations returned to baseline during the three days of follow-up. Conclusions: Our study demonstrates abnormally elevated cTns with well-validated sensitive cTn assays after resistance training. This confirms that different kinds of recreational physical activity are yet another confounder that may affect the determination and use of 99th percentile reference values. Therefore, exercise-associated changes should be carefully addressed as part of the evaluation what is "normal cTn".

  • 38.
    Sillén, Sara
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Photodegradation study of 3,5-diamino-6-chloro- N-(2-(methylamino)ethyl)pyrazine-2-carboxamide using preparative SFC and LC-MS2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this project the photodegradation of 3,5-diamino-6-chloro-N-(2-(methylamino)ethyl)pyrazine-2-carboxamide was studied. A hypothetical degradation pattern for the compound was proposed and the aim of the project was to study the formed secondary photodegradants and to, if possible, structure elucidate some of these compounds. In order to do this, the parent compound was photodegraded in two steps, where a primary photodegradant was isolated using semi-preparative supercritical fluid chromatography (SFC) and then further degraded into the secondary photodegradants.

    The photodegradation was first carried out in aqueous solution, where the parent compound was irradiated in UV-A light of 300-400 nm. This resulted in a primary photodegradant with a molecular ion of m/z = 227, where the chloride in position 6 of the pyrazine group had been replaced by a hydroxyl group. During the large scale photodegradation, prior to the preparative purification, the yield of primary photodegradant was very low due to the photodegradation being dependent on both sample volume and concentration and due to the primary photodegradant also being unstable in aqueous solution at room temperature.

    Due to the above mentioned difficulties the parent compound was photodegraded in methanol instead of water in order to avoid the freeze-drying process where a lot of the primary photodegradant was lost. This resulted in a primary photodegradant with a molecular ion of m/z = 241, where the chloride had been replaced by a methoxy group instead of a hydroxyl group. This compound was more stable which allowed workup by rotary evaporation, instead of freeze-drying, before the preparative purification. This primary photodegradant was isolated using semi-preparative SFC on a Viridis® BEH Prep OBD TM column (250 x 30 mm, 5 µm) and a Luna HILIC column (250 x 30 mm, 5 µm) with MeOH/NH3 100/1 v/v as organic modifier. About 1.2 mg material was isolated and further photodegradation tests in ordinary water and 18O-water were conducted.

    Some secondary photodegradants were observed in LC-MS analyses, and their element compositions were proposed by accurate mass results. Fundamental structures for these compounds were proposed. Further structural investigational analyses are needed for confirmation in the future.

  • 39.
    Skorpil, Mikael
    et al.
    Umeå Univ, Dept Radiat Sci, Umeå, Sweden..
    Brynolfsson, P.
    Umea Univ, Dept Radiat Sci, Umea, Sweden..
    Engström, M.
    GE Healthcare, Appl Sci Lab, Uppsala, Sweden..
    Motion corrected DWI with integrated T2-mapping for simultaneous estimation of ADC, T2-relaxation and perfusion in prostate cancer2017In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 39, p. 162-167Article in journal (Refereed)
    Abstract [en]

    Objective: Multiparametric magnetic resonance imaging (MRI) and PI-RADS (Prostate Imaging - Reporting and Data System) has become the standard to determine a probability score for a lesion being a clinically significant prostate cancer. T2-weighted and diffusion-weighted imaging (DWI) are essential in PI-RADS, depending partly on visual assessment of signal intensity, while dynamic-contrast enhanced imaging is less important. To decrease inter-rater variability and further standardize image evaluation, complementary objective measures are in need.

    Methods: We here demonstrate a sequence enabling simultaneous quantification of apparent diffusion coefficient (ADC) and T2-relaxation, as well as calculation of the perfusion fraction f from low b-value intravoxel incoherent motion data. Expandable wait pulses were added to a FOCUS DW SE-EPI sequence, allowing the effective echo time to change at run time. To calculate both ADC and f, b-values 200 s/mm² and 600 s/mm² were chosen, and for T2-estimation 6 echo times between 64.9 ms and 114.9 ms were used.

    Results: Three patients with prostate cancer were examined and all had significantly decreased ADC and T2 values, while f was significantly increased in 2 of 3 tumors. T2 maps obtained in phantom measurements and in a healthy volunteer were compared to T2 maps from a SE sequence with consecutive scans, showing good agreement. In addition, a motion correction procedure was implemented to reduce the effects of prostate motion, which improved T2-estimation.

    Conclusions: This sequence could potentially enable more objective tumor grading, and decrease the inter-rater variability in the PI-RADS classification.

  • 40. Starnberg, Karin
    et al.
    Jeppsson, Anders
    Lindahl, Bertil
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Hammarsten, Ola
    Revision of the Troponin T Release Mechanism from Damaged Human Myocardium2014In: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 60, no 8, p. 1098-1104Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Cardiac troponin T (cTnT) is released from damaged heart tissue in patients with acute myocardial infarction. It is presumed that most cTnT is tightly bound and released following the degradation of myofibrils in necrotic cardiomyocytes, resulting in sustained increases in circulating cTnT. Evidence of a large irreversibly bound fraction is based on the inability to extract most cTnT from cardiac tissue in cold low-salt extraction buffers. METHODS: Here we examined in vitro extraction of cTnT from human cardiac tissue in serum at 37 degrees C. RESULTS: We found that over 80% of the cTnT can be extracted from human cardiac tissue in 90 min using large volumes of human serum at 37 degrees C. The release ratio was highly dependent on the extraction volume and was only 3% if an equal volume of serum and heart tissue was used. In contrast, extraction of the cytoplasmic cardiac damage markers myoglobin and creatinine kinase was much less affected by changing these conditions. Purified cTnT was poorly soluble in a low-salt extraction buffer at 0 degrees C, previously used to define the free cTnT fraction. CONCLUSIONS: Our data indicate that the diffusible fraction of cTnT is likely substantially larger in vivo than previously reported and likely is not fixed but dependent on local plasma flow. It is therefore possible that the sustained increase in circulating cTnT after myocardial infarction is at least in part due to a slow washout of cTnT that interacts reversibly with tropomyosin in myofibrils.

  • 41.
    Strese, Åke
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Principles for Diverting and Merging Viscous Flows: Evaluation and Visualisation2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the chemistry branch of science is often a chromatograph usedto separate and purify substances in a solution. In achromatograph, different detectors are used to analyse the samplesconstituents. Some detectors destroy the sample during analysis.Because it is undesirable to destroy the entire flow of sample, asmall mass is transferred to a second flow by a flow splitter. Inthis report, four principles to divert a small mass from one flowto another are developed and evaluated. The basic principles todivert the flows is tested and principal mock-ups are designed andmanufactured. A brief survey of the market is conducted and aproblem related to flow spitting is investigated. The problem isthe influence on yield through a chromatograph due to flowretaining. Designing and testing of different retaining systems isalso included in this report.

    All four initial principles proved to be plausible splittingtechniques. However, only two principles appeared to be feasiblefor direct implementation in devices comparable withchromatographs. One of the less feasible principle is covered byseveral patents. The other is difficult to manufacture in order tomeet the strict requirements associated with e.g. chromatographs.The testing of different retaining systems showed that smallertube inner diameter and how the tube is winded can reduce theretaining system influence on the yield significantly.

    The splitting techniques in this report are all feasible splittingtechniques, and the report can be used as a solid foundation fordevelopment future laboratory instruments.

  • 42.
    Tian, Bo
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Ma, Jing
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Zardán Gómez de la Torre, Teresa
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Donolato, Marco
    Technical University of Denmark.
    Fougt Hansen, Mikkel
    Technical University of Denmark.
    Svedlindh, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Strömberg, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Rapid Newcastle Disease Virus Detection based on Loop-Mediated Isothermal Amplification and Optomagnetic Readout2016In: ACS Sensors, ISSN 2379-3694, Vol. 1, no 10, p. 1228-1234Article in journal (Refereed)
    Abstract [en]

    Rapid and sensitive diagnostic methods based on isothermal amplification are ideal substitutes for PCR in out-of-lab settings. However, there are bottlenecks in terms of establishing low-cost and user-friendly readout methods for isothermal amplification schemes. Combining the high amplification efficiency of loop-mediated isothermal amplification (LAMP) with an optomagnetic' nanoparticle-based readout system, we demonstrate ultrasensitive and rapid detection of Newcastle disease virus RNA. Biotinylated amplicons of LAMP and reverse transcription LAMP (RT-LAMP) bind to streptavidin-coated magnetic nanoparticles (MNPs) resulting in a dramatical increase in the hydrodynamic size of the MNPs. This increase was measured by an optomagnetic readout system and provided quantitative information on the amount of LAMP target sequence. Our assay resulted in a limit of detection of 10 aM of target sequence with a total assay time of 30 min. The assay has also been tested on clinical samples (vaccine and tissue specimens) with a performance comparable to real-time RT-PCR By changing the LAMP primers, this strategy can serve as a general method for the detection of other DNA/RNA targets with high specificity and sensitivity.

  • 43.
    Viereckel, Thomas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    United in Diversity: A Physiological and Molecular Characterization of Subpopulations in the Basal Ganglia Circuitry2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Basal Ganglia consist of a number of different nuclei that form a diverse circuitry of GABAergic, dopaminergic and glutamatergic neurons. This complex network is further organized in subcircuits that govern limbic and motor functions in humans and other vertebrates. Due to the interconnection of the individual structures, dysfunction in one area or cell population can affect the entire network, leading to synaptic and molecular alterations in the circuitry as a whole. The studies in this doctoral thesis aimed at characterizing restricted subpopulations of neurons in the Basal Ganglia circuitry and their importance in the wider function of the network. To this end, we identified subpopulations of neurons in the subthalamic nucleus (STN), substantia nigra (SN) and ventral tegmental area (VTA), characterized their molecular profile and investigated their physiological role in the circuitry.

    Within the mouse STN, reduction of glutamatergic neurotransmission in a subpopulation expressing Paired-like homeodomain transcription factor 2 (Pitx2) led to structural alterations in the nucleus as well as biochemical alterations of the dopaminergic system in the Nucleus accumbens (NAc) and changes in reward-related behavior. In the ventral midbrain, we identified and characterized novel marker genes selective to the VTA or SN. Of these, transient receptor potential cation channel subfamily V member 1 (TrpV1) marks a population of mainly glutamatergic neurons in the VTA which project to the NAc, while gastrin releasing peptide (Grp) is expressed in a population of dopaminergic neurons neuroprotected in Parkinson's disease. Furthermore, we discovered that disruption of glutamatergic co-release of dopaminergic neurons expressing dopamine transporter (DAT), diminishes fast EPSCs and glutamate release but does not affect the acquisition of reward-related behavioral tasks. To selectively quantify glutamate release from specific subpopulations, we devised a technique combining glutamate-amperometry and optogenetics. This was used to measure glutamate released from Pitx2-expressing synaptic terminals in the Globus pallidus as well as DAT- or TrpV1-expressing terminals in the NAc.

    In summary, this doctoral thesis has furthered understanding of the function and importance of specific subpopulations within the Basal Ganglia circuitry and provides a novel means to investigate glutamate in the intact rodent brain within clearly defined, restricted cell populations.

    List of papers
    1. Reduced Vglut2/Slc17a6 Gene Expression Levels throughout the Mouse Subthalamic Nucleus Cause Cell Loss and Structural Disorganization Followed by Increased Motor Activity and Decreased Sugar Consumption
    Open this publication in new window or tab >>Reduced Vglut2/Slc17a6 Gene Expression Levels throughout the Mouse Subthalamic Nucleus Cause Cell Loss and Structural Disorganization Followed by Increased Motor Activity and Decreased Sugar Consumption
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    2016 (English)In: ENEURO, ISSN 2373-2822, Vol. 3, no 5, article id UNSP e0264Article in journal (Refereed) Published
    Abstract [en]

    The subthalamic nucleus (STN) plays a central role in motor, cognitive, and affective behavior. Deep brain stimulation (DBS) of the STN is the most common surgical intervention for advanced Parkinson's disease (PD), and STN has lately gained attention as target for DBS in neuropsychiatric disorders, including obsessive compulsive disorder, eating disorders, and addiction. Animal studies using STN-DBS, lesioning, or inactivation of STN neurons have been used extensively alongside clinical studies to unravel the structural organization, circuitry, and function of the STN. Recent studies in rodent STN models have exposed different roles for STN neurons in reward-related functions. We have previously shown that the majority of STN neurons express the vesicular glutamate transporter 2 gene (Vglut2/Slc17a6) and that reduction of Vglut2 mRNA levels within the STN of mice [conditional knockout (cKO)] causes reduced postsynaptic activity and behavioral hyperlocomotion. The cKO mice showed less interest in fatty rewards, which motivated analysis of reward-response. The current results demonstrate decreased sugar consumption and strong rearing behavior, whereas biochemical analyses show altered dopaminergic and peptidergic activity in the striatum. The behavioral alterations were in fact correlated with opposite effects in the dorsal versus the ventral striatum. Significant cell loss and disorganization of the STN structure was identified, which likely accounts for the observed alterations. Rare genetic variants of the human VGLUT2 gene exist, and this study shows that reduced Vglut2/Slc17a6 gene expression levels exclusively within the STN of mice is sufficient to cause strong modifications in both the STN and the mesostriatal dopamine system.

    Keywords
    dopamine, dynorphin, glutamate, rearing, reward, self-administration
    National Category
    Neurology
    Identifiers
    urn:nbn:se:uu:diva-315932 (URN)10.1523/ENEURO.0264-16.2016 (DOI)000391930400042 ()
    Funder
    Swedish Research Council, Vetenskapsradet 2013-4657 2014-3804 2011-4423 2015-4870 2012-2304The Swedish Brain FoundationÅke Wiberg Foundation
    Available from: 2017-02-22 Created: 2017-02-22 Last updated: 2017-09-05Bibliographically approved
    2. Midbrain Gene Screening Identifies a New Mesoaccumbal Glutamatergic Pathway and a Marker for Dopamine Cells Neuroprotected in Parkinson's Disease
    Open this publication in new window or tab >>Midbrain Gene Screening Identifies a New Mesoaccumbal Glutamatergic Pathway and a Marker for Dopamine Cells Neuroprotected in Parkinson's Disease
    Show others...
    2016 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 35203Article in journal (Refereed) Published
    Abstract [en]

    The ventral tegmental area (VTA) and substantia nigra pars compacta (SNc) of the midbrain are associated with Parkinson's disease (PD), schizophrenia, mood disorders and addiction. Based on the recently unraveled heterogeneity within the VTA and SNc, where glutamate, GABA and co-releasing neurons have been found to co-exist with the classical dopamine neurons, there is a compelling need for identification of gene expression patterns that represent this heterogeneity and that are of value for development of human therapies. Here, several unique gene expression patterns were identified in the mouse midbrain of which NeuroD6 and Grp were expressed within different dopaminergic subpopulations of the VTA, and TrpV1 within a small heterogeneous population. Optogenetics-coupled in vivo amperometry revealed a previously unknown glutamatergic mesoaccumbal pathway characterized by TrpV1-Cre-expression. Human GRP was strongly detected in non-melanized dopaminergic neurons within the SNc of both control and PD brains, suggesting GRP as a marker for neuroprotected neurons in PD. This study thus unravels markers for distinct subpopulations of neurons within the mouse and human midbrain, defines unique anatomical subregions within the VTA and exposes an entirely new glutamatergic pathway. Finally, both TRPV1 and GRP are implied in midbrain physiology of importance to neurological and neuropsychiatric disorders.

    National Category
    Neurology
    Identifiers
    urn:nbn:se:uu:diva-307529 (URN)10.1038/srep35203 (DOI)000385768100001 ()27762319 (PubMedID)
    Funder
    Swedish Research Council, 2013-4657 2014-3804The Swedish Brain FoundationÅke Wiberg Foundation
    Available from: 2016-11-17 Created: 2016-11-17 Last updated: 2017-11-29Bibliographically approved
    3. Disrupting Glutamate Co-transmission Does Not Affect Acquisition of Conditioned Behavior Reinforced by Dopamine Neuron Activation
    Open this publication in new window or tab >>Disrupting Glutamate Co-transmission Does Not Affect Acquisition of Conditioned Behavior Reinforced by Dopamine Neuron Activation
    Show others...
    2017 (English)In: Cell reports, ISSN 2211-1247, E-ISSN 2211-1247, Vol. 18, no 11, p. 2584-2591Article in journal (Refereed) Published
    Abstract [en]

    Dopamine neurons in the ventral tegmental area (VTA) were previously found to express vesicular glutamate transporter 2 (VGLUT2) and to co-transmit glutamate in the ventral striatum (VStr). This capacity may play an important role in reinforcement learning. Although it is known that activation of the VTA-VStr dopamine system readily reinforces behavior, little is known about the role of glutamate co-transmission in such reinforcement. By combining electrode recording and optogenetics, we found that stimulation of VTA dopamine neurons in vivo evoked fast excitatory responses in many VStr neurons of adult mice. Whereas conditional knockout of the gene encoding VGLUT2 in dopamine neurons largely eliminated fast excitatory responses, it had little effect on the acquisition of conditioned responses reinforced by dopamine neuron activation. Therefore, glutamate co-transmission appears dispensable for acquisition of conditioned responding reinforced by DA neuron activation.

    Keywords
    glutamate co-transmission, intracranial self-stimulation, mesolimbic dopamine system, nucleus accumbens, reinforcement learning, reward, ventral striatum
    National Category
    Cell and Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-318762 (URN)10.1016/j.celrep.2017.02.062 (DOI)000397330000005 ()28297663 (PubMedID)
    Funder
    NIH (National Institute of Health)Swedish Research Council, 2013-4657 2014-3804The Swedish Brain Foundation
    Available from: 2017-03-28 Created: 2017-03-28 Last updated: 2018-09-21Bibliographically approved
    4. A Physiological Insight into Real-Time Glutamate Release upon Optogenetic Stimulation in vivo
    Open this publication in new window or tab >>A Physiological Insight into Real-Time Glutamate Release upon Optogenetic Stimulation in vivo
    2017 (English)Article in journal (Other academic) Submitted
    National Category
    Neurosciences
    Identifiers
    urn:nbn:se:uu:diva-328036 (URN)
    Available from: 2017-08-16 Created: 2017-08-16 Last updated: 2018-01-13
  • 44.
    Waldmann, Andreas D.
    et al.
    Swisstom AG, Landquart, Switzerland..
    Ferrando Ortola, Carlos
    Hosp Clin Univ, Dept Anesthesia & Crit Care, Valencia, Spain..
    Munoz Martinez, Manuel
    Hosp Univ Princesa, Dept Anesthesiol, Madrid, Spain..
    Vidal, Anxela
    Inst Invest Sanitaria Fdn Jimenez Diaz, Dept Crit Care, Madrid, Spain..
    Santos, Arnoldo
    Inst Invest Sanitaria Fdn Jimenez Diaz, Dept Crit Care, Madrid, Spain..
    Perez Marquez, Manuel
    Inst Invest Sanitaria Fdn Jimenez Diaz, Dept Crit Care, Madrid, Spain..
    Roka, Peter L.
    Swisstom AG, Landquart, Switzerland..
    Bohm, Stephan H.
    Swisstom AG, Landquart, Switzerland..
    Suarez-Sipmann, Fernando
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Hedenstierna laboratory.
    Position-dependent distribution of lung ventilation - A feasability study2015In: 2015 IEEE Sensors Applications Symposium (SAS), 2015, p. 429-434Conference paper (Refereed)
    Abstract [en]

    The aim of this feasibility study was to determine whether the measurement setup and study protocol were able to show the effect that lung disease, body position and different levels of positive end expiratory pressure (PEEP) have on lung function. By means of a motorized rotation table and gravity sensors six pigs were rotated in steps of 30 degrees from left to right lateral position. Regional ventilation distributions, measured by electrical impedance tomography (EIT), oxygenation and compliance measurements were performed at each position. Both, experimental and measurement setup as well as the parameters chosen to characterize lung function appear suitable for analyzing the effects of PEEP and rotation in healthy and injured lungs. The initial results show that the distribution of regional ventilation was highly gravity-dependent especially in sick lungs. Furthermore lateral rotation showed significant recruitment effects on previously collapsed lung tissue as witnessed by the increases in oxygenation at all PEEPs.

  • 45.
    Werr, Gabriel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Khaji, Zahra
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Ohlin, Mathias
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Andersson, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Klintberg, Lena
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology.
    Searle, Sean
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab. Department of Biomedical Engineering, National University of Singapore, Singapore 117583, Singapore.
    Hjort, Klas
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology, Ångström Space Technology Centre (ÅSTC). Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Integrated thin film resistive sensors for in situ temperature measurements in an acoustic trap2019In: Acoustofluidics 2019: This annual meeting will be held in Twente, The Netherlands in 2019. This focused meeting is dedicated to exploring the science, engineering, and use of micro- to nanoscale acoustofluidics., 2019, p. 140-141Conference paper (Other academic)
    Abstract [en]

    This work presents an acoustic trap with integrated thin film sensors to monitor temperature variations during operation. The acoustic trap is wet-etched in glass with a thermally bonded glass lid and the thin-film sensors are integrated during fabrication. We evaluated the performance of the integrated temperature sensors and measured a temperature sensitivity of ±0.01 °C and confirmed that the read-out of the thin film sensors was not affected neither by the ionic conducitiviy of the solution nor the addition of microparticles into the acoustic trap. From the experiments we observed a temperature increase of the acoustic trap during operation as a result of the dissipative heating of the the piezoelectric element used to actuate the trap. We also showed that when external convective cooling was applied to the system, the temperature increase of the acoustic trap was higher than the temperature incresase of the piezoelectric element itself. This shows the importance of using integrated temperature sensors in acoustic trapping to monitor the environmental conditions.

  • 46.
    Wolff, Anette
    et al.
    Dept. Biomedical Engineering Lund University, Lund.
    Thomée, Emma
    Dept. Biomedical Engineering Lund University, Lund..
    Wallman, Lars
    Dept. Biomedical Engineering Lund University, Lund..
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Assembly of a microfluidic device using only plasma activation2017Conference paper (Refereed)
    Abstract [en]

    The blood-brain barrier (BBB) is a complex system, and essential for normal brainfunction as it protects the brain from harmful substances and changes in the blood composition.To analyse the BBB, the simplest way is by using in vitro models, and by utilising microfluidicdevices it is possible to integrate several parameters and analysis steps into one device. We havedeveloped a stable and reproducible bonding protocol for assembling a PDMS-based microfluidicdevice using only plasma activation, to remove the dimensional uncertainty of using intermediatelayer adhesives.

  • 47.
    Wolff, Anette
    et al.
    Dept. Biomedical Engineering Lund University, Lund.
    Thomée, Emma
    Dept. Biomedical Engineering Lund University, Lund..
    Wallman, Lars
    Dept. Biomedical Engineering Lund University, Lund..
    Tenje, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Optimisation of a glass/PDMS/PDMS/glass microfluidic chip assembly using air plasma2017Conference paper (Refereed)
  • 48. Yuen, Pikkei
    Pushing the limits of antibioticsusceptibility testing: - an image analysis approach2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 49. Zeng, Ruixue
    et al.
    Zhang, Junkai
    Yang, Hui
    Sun, Cuiling
    Xu, Ming
    Zhang, Shi-Li
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Wu, Dongping
    Modelling and Characterization of Novel Reference-Less Semiconductor Ion Sensor for pH Sensing2019In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 281, p. 60-71Article in journal (Refereed)
    Abstract [en]

    A SPICE macromodel is developed for a novel reference-less semiconductor ion sensor (RELESIS), which has been proposed to eliminate the use of reference electrode in the field effect based sensor detection. The working principle of the RELESIS, previously validated by a prototype device via pH sensing, is featured by non-constant bulk solution potential, which distincts itself from any conventional ion sensitive field effect transistor. Simulations are performed here using the macromodel and the results fit well with the experimental data. The proposed SPICE macromodel can be used to predict the behavior of the RELESIS and carry out performance optimizations for the RELESIS to be used in various applications.

  • 50.
    Zetterström, Henrik
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Jonsson, Lars O
    Kronander, H
    Simulated spontaneous breathing. A new lung model for testing anaesthetic circuits1985In: Acta Anaesthesiologica Scandinavica, Vol. 29, p. 265-268Article in journal (Refereed)
1 - 50 of 50
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