| 61. |
- Iredahl, Fredrik, 1988-
(författare)
-
Assessment of microvascular and metabolic responses in the skin
- 2016
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The general aim of this project was to develop experimental in vivo models that allow for minimally invasive investigations of responses in the skin to microvascular and metabolic provocations. The cutaneous microvasculature has emerged as a valuable model and been proposed to mirror the microcirculation in other organs. Dysfunction in the cutaneous microcirculation has thus been linked to systemic diseases such as hypertension and diabetes mellitus. Models for investigating skin responses could facilitate the understanding of pathophysiological mechanisms as well as effects of drugs.In the first study, three optical measurement techniques (laser Doppler flowmetry (LDF), laser speckle contrast imaging (LSCI) and tissue viability imaging (TiVi)) were compared against each other and showed differences in their ability to detect microvascular responses to provocations in the skin. TiVi was found more sensitive for measurement of noradrenaline-induced vasoconstriction, while LSCI was more sensitive for measurement of vascular occlusion. In the second study, microvascular responses in the skin to iontophoresis of vasoactive drugs were found to depend on the drug delivery protocol. Perfusion half-life was defined and used to describe the decay in the microvascular response to a drug after iontophoresis. In the third study, the role of nitric oxide (NO) was assessed during iontophoresis of insulin. The results showed a NO-dependent vasodilation in the skin by insulin. In the fourth study the vasoactive and metabolic effects of insulin were studied after both local and endogenous administration. Local delivery of insulin increased skin blood flow, paralleled by increased skin concentrations of interstitial pyruvate and lactate, although no change in glucose concentration was observed. An oral glucose load resulted in an increased insulin concentration in the skin paralleled by an increase in blood flow, as measured using the microdialysis urea clearance technique, although no changes in perfusion was measured by LSCI.The thesis concludes that when studying skin microvascular responses, the choice of measurement technique and the drug delivery protocol has an impact on the measurement results, and should therefore be carefully considered. The thesis also concludes that insulin has metabolic and vasodilatory effects in the skin both when administered locally and as an endogenous response to an oral glucose load. The vasodilatory effect of insulin in the skin is mediated by nitric oxide.
|
|
| 62. |
|
|
| 63. |
- Sarve, Hamid, et al.
(författare)
-
Extracting 3D information on bone remodeling in the proximity of titanium implants in SRμCT image volumes.
- 2011
-
Ingår i: Computer methods and programs in biomedicine. - : Elsevier BV. - 1872-7565 .- 0169-2607. ; 102:1, s. 25-34
-
Tidskriftsartikel (refereegranskat)abstract
- Bone-implant integration is measured in several ways. Traditionally and routinely, 2D histological sections of samples, containing bone and the biomaterial, are stained and analyzed using a light microscope. Such histological section provides detailed cellular information about the bone regeneration in the proximity of the implant. However, this information reflects the integration in only a very small fraction, a 10 μm thick slice, of the sample. In this study, we show that feature values quantified on 2D sections are highly dependent on the orientation and the placement of the section, suggesting that a 3D analysis of the whole sample is of importance for a more complete judgment of the bone structure in the proximity of the implant. We propose features describing the 3D data by extending the features traditionally used for 2D-analysis. We present a method for extracting these features from 3D image data and we measure them on five 3D SRμCT image volumes. We also simulate cuts through the image volume positioned at all possible section positions. These simulations show that the measurement variations due to the orientation of the section around the center line of the implant are about 30%.
|
|
| 64. |
- Calon, Tim, et al.
(författare)
-
Multimodal analysis of the tissue response to a bone-anchored hearing implant. : 11. Calon TGA, Johansson ML, Omar O, Shah FA, Budding D, Trobos M, Thomsen P, Stokroos RJ, Palmquist
- 2019
-
Ingår i: 2nd Politzer Society Meeting/2nd World Congress of Otology, 28 May - 1 June, 2019, Warsaw, Poland..
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)
|
|
| 65. |
- Asberg, Marie, et al.
(författare)
-
Novel biochemical markers of psychosocial stress in women.
- 2009
-
Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 4:1
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Prolonged psychosocial stress is a condition assessed through self-reports. Here we aimed to identify biochemical markers for screening and early intervention in women. METHODS: Plasma concentrations of interleukin (IL) 1-alpha, IL1-beta, IL-2, IL-4, IL-6, IL-8, IL-10, interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), thyroid stimulating hormone (TSH), total tri-iodothyronine (TT3), total thyroxine (TT4), prolactin, and testosterone were measured in: 195 women on long-term sick-leave for a stress-related affective disorder, 45 women at risk for professional burnout, and 84 healthy women. RESULTS: We found significantly increased levels of MCP-1, VEGF and EGF in women exposed to prolonged psychosocial stress. Statistical analysis indicates that they independently associate with a significant risk for being classified as ill. CONCLUSIONS: MCP-1, EGF, and VEGF are potential markers for screening and early intervention in women under prolonged psychosocial stress.
|
|
| 66. |
- Ebbers, Tino, 1972-
(författare)
-
Flow Imaging: Cardiac Applications of 3D Cine Phase-Contrast MRI
- 2011
-
Ingår i: Current Cardiovascular Imaging Reports. - : Springer Science and Business Media LLC. - 1941-9074 .- 1941-9066. ; 4:2, s. 127-133
-
Forskningsöversikt (refereegranskat)abstract
- Global and regional blood flow dynamics are of pivotal importance to cardiac function. Fluid mechanical forces can affect hemolysis and platelet aggregation, as well as myocardial remodeling. In recent years, assessment of blood flow patterns based on time-resolved, three-dimensional, three-directional phase-contrast MRI (3D cine PC MRI) has become possible and rapidly gained popularity. Initially, this technique was mainly known for its intuitive and appealing visualizations of the cardiovascular blood flow. Most recently, the technique has begun to go beyond compelling images toward comprehensive and quantitative assessment of blood flow. In this article, cardiac applications of 3D cine PC MRI data are discussed, starting with a review of the acquisition and analysis techniques, and including descriptions of promising applications of cardiac 3D cine PC MRI for the clinical evaluation of myocardial, valvular, and vascular disorders.
|
|
| 67. |
- Skiöld, Sara, et al.
(författare)
-
Radiation-induced stress response in peripheral blood of breast cancer patients differs between patients with severe acute skin reactions and patients with no side effects to radiotherapy
- 2013
-
Ingår i: Mutation research. Genetic toxicology and environmental mutagenesis. - : Elsevier BV. - 1383-5718 .- 1879-3592. ; 756:1-2, s. 152-157
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to compare the radiation-induced oxidative stress response in blood samples from breast cancer patients that developed severe acute skin reactions during the radiotherapy, with the response in blood samples from patients with no side effects. Peripheral blood was collected from 12 breast cancer patients showing no early skin reactions after radiotherapy (RTOG grade 0) and from 14 breast cancer patients who developed acute severe skin reactions (RTOG grade 3-4). Whole blood was irradiated with 0, 5 and 2000 mGy gamma-radiation and serum was isolated. The biomarker for oxidative stress, 8-oxo-dG, was analyzed in the serum by a modified ELISA. While a significant radiation-induced increase of serum 8-oxo-dG levels was observed in serum of the RTOG 0 patients, no increase was seen in serum of the RTOG 3-4 patients. The radiation induced increase in serum 8-oxo-dG levels after 5 mGy did not differ significantly from the increase observed for 2000 mGy in the RTOG 3-4 cohort, thus no dose response relation was observed. A receiver operating characteristic (ROC) value of 0.97 was obtained from the radiation-induced increase in 8-oxo-dG indicating that the assay could be used to identify patients with severe acute adverse reactions to radiotherapy. The results show that samples of whole blood from patients, classified as highly radiosensitive (RTOG 3-4) based on their skin reactions to radiotherapy, differ significantly in their oxidative stress response to ionizing radiation compared to samples of whole blood from patients with no skin reactions (RTOG 0). Extracellular 8-oxo-dG is primarily a biomarker of nucleotide damage and the results indicate that the patients with severe acute skin reactions differ in their cellular response to ionizing radiation at the level of induction of oxidative stress or at the level of repair or both.
|
|
| 68. |
|
|
| 69. |
|
|
| 70. |
- Trigo, João Pedro, 1995, et al.
(författare)
-
Mild blanching prior to pH-shift processing of Saccharina latissima retains protein extraction yields and amino acid levels of extracts while minimizing iodine content
- 2023
-
Ingår i: Food Chemistry. - : Elsevier BV. - 0308-8146 .- 1873-7072. ; 404
-
Tidskriftsartikel (refereegranskat)abstract
- The seaweed Saccharina latissima is often blanched to lower iodine levels, however, it is not known how blanching affects protein extraction. We assessed the effect of blanching or soaking (80/45/12 °C, 2 min) on protein yield and protein extract characteristics after pH-shift processing of S. latissima. Average protein yields and extract amino acid levels ranked treatments as follows: blanching-45 °C ∼ control > soaking ∼ blanching-80 °C. Although blanching-45 °C decreased protein solubilization yield at pH 12, it increased isoelectric protein precipitation yield at pH 2 (p < 0.05). The former could be explained by a higher ratio of large peptides/proteins in the blanched biomass as shown by HP-SEC, whereas the latter by blanching-induced lowering of ionic strength, as verified by a dialysis model. Moreover, blanching-45 °C yielded a protein extract with 49 % less iodine compared with the control extract. We recommend blanching-45 °C since it is effective at removing iodine and does not compromise total protein extraction yield.
|
|
