T cell immunity against early antigens of Human Papillomavirus type 16

UBL - phd migration 201

Remote manipulation of cells with ultrasound and microbubbles

Ultrasound in combination with contrast microbubbles has been shown to alter the permeability of cell membranes. This permeabilization feature is used to design new drug delivery systems using ultrasound and contrast agents. Although the exact underlying mechanisms are still unknown, one hypothesis is that oscillating microbubbles cause cell deformation resulting in enhanced cell membrane permeability. In this paper we show the actions of oscillating microbubbles on cultured cells under a microscope recorded with a fast framing camera at 10 million frames per second. Optical observations of microbubbles and cultured cells is possible through the use of a microscope mounted in front of the fast framing camera Brandaris128. The Brandaris128 is capable of recording a sequence of 128 images with a frame rate up to 25 million frames per second. Pig aorta endothelial cells were grown on the inside of an Opticell/spl trade/ container. A diluted suspension of experimental agents BR14 (Bracco Research, Geneva, Switzerland) was added. Ultrasound exposure consisted of one burst of 6 cycles at a frequency of 1 MHz and a P/spl I.bar/ of 0.5 MPa. During ultrasound transmission, the interactions between BR14 microbubbles and cultured cells were recorded using a frame rate of 10 million frames per second. Cell deformation as a result of vibrating microbubbles is studied. Cell deformation is quantified through measuring the displacement of the cells. Microbubble vibration is quantified by measuring its initial, maximal, and minimal radii. We observed that upon ultrasound arrival and microbubble oscillations, the cell membrane deforms up to a few micrometers in length as a result of the oscillation of the microbubble. The membrane deformation rate changes with the oscillation strength of the microbubble. During the sonication, changes in the cross-sectional distance of the cultured cells were observed due to microbubble vibrations. Depending on the maximal vibrations of the microbubble and the distance between the microbubble and the cell, the displacement of the cells varied form 0 to 20% of the cell size. This study reveals the action of oscillating microbubbles on cells. It is known that living cells sense mechanical forces thus there is no doubt that perturbation of the oscillating microbubbles results in profound alterations in the cellular content. This study is the beginning of revealing the functional relationships that lie beyond the remote manipulation of cells and ultrasound microbubble induced permeabilization of the cell membrane

Designated Communities van Beeld en Geluid: Typering en Uitleveringseisen

This document provides an outline of the NISV’s various internal and external Designated Communities, as identified and documented in 2013. It offers a general decription of each of the DC’s and presents a comprehensive overview of (technical) demands from the distinct user groups as to 1. Delivery, 2. Software/hardware environment and 3. Metadata. As such, the document serves as a baseline audit for continuous Designated Community polling and development, as part of the Digital Archive ‘s preservation watch mechanisms

Coping strategies, anxiety and depressive symptoms in family members of patients treated with extracorporeal membrane oxygenation:A prospective cohort study

BACKGROUND: Family members of patients treated with Extracorporeal Membrane Oxygenation (ECMO) during an Intensive Care Unit (ICU) stay are at risk of developing symptoms of anxiety, depression and Post-Traumatic Stress Disorder (PTSD). Coping strategies used by family members may play an important role in the severity of some of these symptoms.OBJECTIVES: The primary aim of this study was to describe coping strategies used by family members of ECMO-treated patients during ICU admission and recovery period. The secondary aim was to explore the course of the symptoms anxiety, depression, PTSD, and Health Related Quality Of Life (HRQOL) over time.METHODS: In this single-center prospective longitudinal study, validated questionnaires were used to measure coping strategies, symptoms of anxiety, depression and PTSD, and HRQOL in family members of ECMO-treated patients directly after the start of ECMO and at one and six months after the start of ECMO.RESULTS: Family members (n = 26) mainly used problem-focused coping strategies. Symptoms of anxiety appeared to be most present during treatment but decreased over time, as did symptoms of depression and PTSD. HRQOL was severely affected, especially in the mental domain, and did not improve over time.CONCLUSION: In family members of ECMO-treated patients, problem-focused coping mechanisms were most prominent. Psychological functioning was impaired on admission but improved over time, although a mild reaction to stress remained.</p

Ultra-high-speed imaging of bubbles interacting with cells and tissue

Ultrasound contrast microbubbles are exploited in molecular imaging, where bubbles are directed to target cells and where their high-scattering cross section to ultrasound allows for the detection of pathologies at a molecular level. In therapeutic applications vibrating bubbles close to cells may alter the permeability of cell membranes, and these systems are therefore highly interesting for drug and gene delivery applications using ultrasound. In a more extreme regime bubbles are driven through shock waves to sonoporate or kill cells through intense stresses or jets following inertial bubble collapse. Here, we elucidate some of the underlying mechanisms using the 25-Mfps camera Brandaris128, resolving the bubble dynamics and its interactions with cells. We quantify acoustic microstreaming around oscillating bubbles close to rigid walls and evaluate the shear stresses on nonadherent cells. In a study on the fluid dynamical interaction of cavitation bubbles with adherent cells, we find that the nonspherical collapse of bubbles is responsible for cell detachment. We also visualized the dynamics of vibrating microbubbles in contact with endothelial cells followed by fluorescent imaging of the transport of propidium iodide, used as a membrane integrity probe, into these cells showing a direct correlation between cell deformation and cell membrane permeability

Типові схеми використання офшорних та оншорних зон для зменшення податкового навантаження бізнесу в Україні

The proteasome is able to create spliced Ags, in which two distant parts of a protein are excised and ligated together to form a novel peptide, for presentation by MHC class I molecules. These noncontiguous epitopes are generated via a transpeptidation reaction catalyzed by the proteasomal active sites. Transpeptidation reactions in the proteasome follow explicit rules and occur particularly efficiently when the C-terminal ligation partner contains a lysine or arginine residue at the site of ligation. Lysine contains two amino groups that theoretically may both participate in ligation reactions, implying that potentially not only peptide but also isopeptide linkages could be formed. Using nuclear magnetic resonance spectroscopy, we demonstrate in the present study that the proteasome can use the ε-amino group of an N-terminal lysine residue in transpeptidation reactions to create a novel type of posttranslationally modified epitopes. We show that the overall efficiency of ε ligation is only 10-fold lower as compared with α ligation, suggesting that the proteasome can produce sufficient isopeptide Ag to evoke a T cell response. Additionally, we show that isopeptides are more stable toward further proteasomal processing than are normal peptides, and we demonstrate that isopeptides can bind to HLA-A2.1 and HLA-A3 with high affinity. These properties likely increase the fraction of ε-ligated peptides presented on the cell surface for CD8+ T cell surveillance. Finally, we show that isopeptide Ags are immunogenic in vivo. We postulate that ε ligation is a genuine posttranslational modification, suggesting that the proteasome can create a novel type of Ag that is likely to play a role in immunity

RNA isolation for transcriptomics of human and mouse small skin biopsies

<p>Abstract</p> <p>Background</p> <p>Isolation of RNA from skin biopsies presents a challenge, due to the tough nature of skin tissue and a high presence of RNases. As we lacked the dedicated equipment, i.e. homogenizer or bead-beater, needed for the available RNA from skin isolation methods, we adapted and tested our zebrafish single-embryo RNA-isolation protocol for RNA isolation from skin punch biopsies.</p> <p>Findings</p> <p>We tested our new RNA-isolation protocol in two experiments: a large-scale study with 97 human skin samples, and a small study with 16 mouse skin samples. Human skin was sampled with 4.0 mm biopsy punches and for the mouse skin different punch diameter sizes were tested; 1.0, 1.5, 2.0, and 2.5 mm. The average RNA yield in human samples was 1.5 μg with an average RNA quality RIN value of 8.1. For the mouse biopsies, the average RNA yield was 2.4 μg with an average RIN value of 7.5. For 96% of the human biopsies and 100% of the mouse biopsies we obtained enough high-quality RNA. The RNA samples were successfully tested in a transcriptomics analysis using the Affymetrix and Roche NimbleGen platforms.</p> <p>Conclusions</p> <p>Using our new RNA-isolation protocol, we were able to consistently isolate high-quality RNA, which is apt for further transcriptomics analysis. Furthermore, this method is already useable on biopsy material obtained with a punch diameter as small as 1.5 mm.</p