Citation guide

The German version of the citation guide is available at https://doi.org/10.21256/zhaw-24167

Respiration induced oxygen gradients in cultured mammalian cells

Oxygen is known to sensitize X-irradiated cells to lethal radiation damage. At low ambient oxygen tensions, however, the molecular mechanisms of the sensitization process and the metabolic requirements of the cell may be forced to compete for the cellular oxygen supply. The effect of cell respiration on the availability of intracellular oxygen during irradiation was consequently investigated by comparing the radiosensitivities of respiring and non-respiring cells. Cultured mammalian cells were irradiated in single cell suspensions and thin film monolayers at respiration inhibiting (4°C) and at normal cell culturing (37°C) temperatures. Due to oxygen equilibration and radiolytic depletion problems, the results of the suspension culture experiments were inconclusive. By subsequently analyzing the diffusive mass transfer of oxygen in the suspension medium, the stirrer flask was determined to be an inappropriate culture vessel in which to irradiate cells at constant low oxygen concentrations. A thin film cell culture system in which the oxygen concentrations to which the cells were exposed during irradiation could be more accurately controlled was then developed. A comparison of the oxygen enhanced radiosensitivities of the respiring and non-respiring cells in thin film monolayers suggested that the metabolic depletion of oxygen at low oxygen tensions has a significant effect on the local and intracellular oxygen distribution. These effects are representative of those that would be produced if respiration induced oxygen gradients existed inside and immediately around respiring cells. The magnitude of the differential radiosensitivities was found to be dependent on cell shape and to have values that agreed very well with theoretical predictions based on the existence of such gradients.Science, Faculty ofPhysics and Astronomy, Department ofGraduat

Improved patient satisfaction and diagnostic accuracy in skin diseases with a Visual Clinical Decision Support System-A feasibility study with general practitioners.

Patient satisfaction is an important indicator of health care quality, and it remains an important goal for optimal treatment outcomes to reduce the level of misdiagnoses and inappropriate or absent therapeutic actions. Digital support tools for differential diagnosis to assist clinicians in reaching the correct diagnosis may be helpful, but how the use of these affect patients is not clear. The primary objective of this feasibility study was to investigate patient experience and satisfaction in a primary care setting where general practitioners (GPs) used a visual clinical decision support system (CDSS) compared with standard consultations. Secondary objectives were diagnostic accuracy and length of consultation. Thirty-one patients with a dermatologist-confirmed skin diagnosis were allocated to consult GPs that had been randomized to conduct either standard consultations (SDR, n = 21) or CDSS (n = 16) on two separate study days one week apart. All patients were diagnosed independently by multiple GPs (n = 3-8) in both the SDR and CDSS study arms. Using the CDSS, more patients felt involved in the decision making (P = 0.05). In addition, more patients were exposed to images during the consultations (P = 6.8e-27), and 83% of those that were shown images replied they felt better supported in the consultation. The use of CDSS significantly improved the diagnostic accuracy (34%, P = 0.007), and did not increase the duration of the consultation (median 10 minutes in both arms). This study shows for the first time that compared with standard GP consultations, CDSS assist the GP on skin related diagnoses and improve patient satisfaction and diagnostic accuracy without impacting the duration of the consultations. This is likely to increase correct treatment choices, patient adherence, and overall result in better healthcare outcomes

Renal denervation for treating hypertension: current scientific and clinical evidence

Initial studies of catheter-based renal denervation (RDN) for uncontrolled HTN using radiofrequency ablation in the main renal arteries showed that RDN was effective in lowering office blood pressure (BP). However, the first randomized sham-controlled trial, SYMPLICITY-HTN-3, did not show significantly lower office or 24-h ambulatory systolic BP compared with sham treatment. Subsequent studies in both animals and humans demonstrated the potential importance of more distal and branch renal artery radiofrequency ablation, and a second-generation multielectrode system became available. Two recent randomized sham-controlled trials in patients not taking antihypertensive drugs (SPYRAL HTN-OFF MED) or continuing to take drugs (SPYRAL HTN-ON MED) performed RDN with the second-generation radiofrequency ablation system using an ablation protocol that included treatment of the distal renal artery as well as the branch renal arteries. These studies showed that RDN significantly reduced office and 24-h ambulatory BP compared with sham treatment. Another recent randomized sham-controlled trial in patients not receiving medications showed that RDN with catheter-based ultrasound (RADIANCE-HTN SOLO) applied in just the main renal arteries significantly lowered daytime ambulatory and office BP compared with sham treatment. These trials have renewed clinical and scientific interest in defining the appropriate role of RDN in hypertension treatment. In addition, other important issues will need to be addressed in the future such as the development of tests to determine the extent of RDN at the time of the procedure and the potential of renal nerve fibers to regain their patency at some later stage following the ablation procedure

Regulatory Aspects of Optical Methods and Exogenous Targets for Cancer Detection

Considerable advances in cancer-specific optical imaging have improved the precision of tumor resection. In comparison to traditional imaging modalities, this technology is unique in its ability to provide real-time feedback to the operating surgeon. Given the significant clinical implications of optical imaging, there is an urgent need to standardize surgical navigation tools and contrast agents to facilitate swift regulatory approval. Because fluorescence-enhanced surgery requires a combination of both device and drug, each may be developed in conjunction, or separately, which are important considerations in the approval process. This report is the result of a one-day meeting held on May 4, 2016 with officials from the National Cancer Institute, the FDA, members of the American Society of Image-Guided Surgery, and members of the World Molecular Imaging Society, which discussed consensus methods for FDA-directed human testing and approval of investigational optical imaging devices as well as contrast agents for surgical applications. The goal of this workshop was to discuss FDA approval requirements and the expectations for approval of these novel drugs and devices, packaged separately or in combination, within the context of optical surgical navigation. In addition, the workshop acted to provide clarity to the research community on data collection and trial design. Reported here are the specific discussion items and recommendations from this critical and timely meeting. Cancer Res; 77(9); 2197-206. ©2017 AACR

La Precariedad te hace dócil: problemas que afectan a la profesión periodística

Se muestran los problemas que son percibidos como los más importantes por los periodistas de cuatro comunidades autónomas españolas: Catalunya, Madrid, País Vasco y Andalucía. De acuerdo con los resultados obtenidos en un trabajo de campo que mezcla metodología cuantitativa y cualitativa, la precariedad y la inseguridad laboral son los problemas que más preocupan a los periodistas de todas las comunidades consultadas. Las variables, edad, sexo e ideología son las que ofrecen más diferencias en las respuestas.The problems that are perceived as the most important by journalists from four Spanish regions: Catalonia, Madrid, Basque Country and Andalusia are reported. Fieldwork using both quantitative and qualitative methods found that precarious and uncertain job security are the issues of most concern to journalists in all the regions surveyed. Of the variables analyzed, age, sex and ideology accounted for the greatest differences in responses