Juha Korhonen

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Future cellular networks such as IMT-Advanced are expected to allow underlaying direct Device-to-Device (D2D) communication for spectrally efficient support of e.g. rich multimedia local services. Enabling D2D links in a cellular network presents a challenge in radio resource management due to the potentially severe interference it may cause to the cellular(More)
ATP-binding cassette transporter A1 (ABCA1) mediates reverse cholesterol transport and innate immunity response in different cell types. We have investigated the regulation of ABCA1 expression in response to intracellular Chlamydia pneumoniae infection in A549 epithelial lung carcinoma cells. C. pneumoniae infection decreased ABCA1 expression in A549 cells,(More)
A gram-negative obligate intracellular bacterium, Chlamydia pneumoniae, is a common respiratory pathogen. Here, we examined the invasion and attachment of C. pneumoniae K6 into nonphagocytic HL epithelial cell line by manipulating host plasma membranes by using cholesterol-depleting methyl-beta-cyclodextrin (MβCD) and cholesterol-loading MβCD complexed(More)
Chlamydiae are obligate intracellular pathogens replicating only inside the eukaryotic host. Here, we studied the effect of human flotillin-1 protein on Chlamydia pneumoniae growth in human line (HL) and A549 epithelial cell lines. RNA interference was applied to disrupt flotillin-1-mediated endocytosis. Host-associated bacteria were detected by(More)
PURPOSE The lack of electron density information in magnetic resonance images (MRI) poses a major challenge for MRI-based radiotherapy treatment planning (RTP). In this study the authors convert MRI intensity values into Hounsfield units (HUs) in the male pelvis and thus enable accurate MRI-based RTP for prostate cancer patients with varying tissue anatomy(More)
PURPOSE This study introduces methods to conduct image-guided radiotherapy (IGRT) of the pelvis with either cone-beam computed tomography (CBCT) or planar localization images by relying solely on magnetic resonance imaging (MRI)-based reference images. MATERIAL AND METHODS Feasibility of MRI-based reference images for IGRT was evaluated against kV CBCT(More)
BACKGROUND Adaptive radiation therapy (ART) for urinary bladder cancer has emerged as a promising alternative to conventional RT with potential to minimize radiation-induced toxicity to healthy tissues. In this work we have studied bladder volume variations and their effect on healthy bladder dose sparing and intrafractional margins, in order to refine our(More)
PURPOSE Magnetic resonance (MR) images are used increasingly in external radiotherapy target delineation because of their superior soft tissue contrast compared to computed tomography (CT) images. Nevertheless, radiotherapy treatment planning has traditionally been based on the use of CT images, due to the restrictive features of MR images such as lack of(More)
BACKGROUND This work evaluates influences of susceptibility-induced bone outline shift and perturbations, and bone segmentation errors on external radiotherapy dose calculation accuracy in magnetic resonance imaging (MRI)-based pseudo-computed tomography (CT) images of the male pelvis. MATERIAL AND METHODS T₁/T₂*-weighted fast gradient echo, T₁-weighted(More)
T helper cells (Th) are divided into Th1 and Th2 subsets based upon their cytokine profiles and function. Naïve Th cells differentiate into Th1 and Th2 subsets depending on the antigens, costimulatory molecules, and cytokines they encounter. Cytokine interleukin (IL)-12 enhances the generation of Th1 lymphocytes and inhibits the production of Th2 subset.(More)