1. |
|
|
2. |
- Adolfsson, Emelie, et al.
(author)
-
Investigation of signal fading in lithium formate EPR dosimeters using a new sensitive method
- 2012
-
In: Physics in Medicine and Biology. - : Institute of Physics (IOP). - 0031-9155 .- 1361-6560. ; 57:8, s. 2209-2217
-
Journal article (peer-reviewed)abstract
- The aim of this study was to investigate signal fading in lithium formate electron paramagnetic resonance (EPR) dosimeters used for clinical applications in radiotherapy. A new experimental method for determination of signal fading, designed to resolve small changes in signal from slowly decaying unstable radicals, was used. Possible signal fading in lithium formate due to different storage temperatures was also tested. Air humidity was kept at a constant level of 33% throughout the experiments. The conclusion drawn from the investigations was that the EPR signal from lithium formate is stable during at least 1 month after irradiation and is not sensitive to variations in storage temperature andlt;40 degrees C when kept at a relative air humidity of 33%. This makes lithium formate a suitable dosimeter for transfer dosimetry in clinical audits.
|
|
3. |
- Altena, Renske, et al.
(author)
-
Human Epidermal Growth Factor Receptor 2 (HER2) PET Imaging of HER2-Low Breast Cancer with [ 68 Ga]Ga-ABY-025 : Results from a Pilot Study
- 2024
-
In: Journal of Nuclear Medicine. - : Society of Nuclear Medicine and Molecular Imaging. - 0161-5505 .- 1535-5667. ; 65:5, s. 700-707
-
Journal article (peer-reviewed)abstract
- Patients with HER2-low metastatic breast cancer (mBC), defined as an immunohistochemistry (IHC) score of 1+ or 2+ without HER2 gene amplification, may benefit from HER2 antibody-drug conjugates. Identifying suitable candidates is a clinical challenge because of spatial and temporal heterogeneity in HER2 expression and discrepancies in pathologic reporting. We aimed to investigate the feasibility and safety of HER2-specific PET imaging with [ 68 Ga]Ga-ABY-025 for visualization of HER2-low mBC.Methods: A prospective pilot study was done with 10 patients who had HER2-low mBC, as part of a phase 2 basket imaging study with [ 68 Ga]Ga-ABY-025 in HER2-expressing solid tumors. Patients were recruited at the Breast Clinic at the Karolinska University Hospital, Stockholm, Sweden. PET/CT images were acquired 3 h after injection of 200 MBq of [ 68 Ga]Ga-ABY-025. The SUV max was used to quantify tracer uptake. Ultrasound-guided tumor biopsies were guided by results from the HER2 PET. The main outcome-the safety and feasibility of HER2 PET in patients with HER2low mBC, measured the occurrence of possible procedure -related adverse events.Results: Ten patients with HER2-low mBC underwent [ 68 Ga]Ga-ABY-025 PET/CT with paired tumor biopsies. No adverse events occurred. In all patients, [ 68 Ga]Ga-ABY-025-avid lesions with substantial intra- and interindividual heterogeneity in tracer uptake were noted. In 8 of 10 patients with ABY-025-avid lesions, the HER2low status of the corresponding lesions was confirmed by IHC or in situ hybridization. Two patients had an IHC score of 0 in the tumor biopsies:1 in a cutaneous lesion with a low SUV max and 1 in a liver metastasis with a high SUV max but a "cold" core.Conclusion: The visualization of HER2-low mBC with [ 68 Ga]Ga-ABY-025 PET/CT was feasible and safe. Areas of tracer uptake showed varying levels of HER2 expression on IHC. The observed intra- and interindividual heterogeneity in [ 68 Ga]Ga-ABY-025 uptake suggested that HER2 PET might be used as a tool for the noninvasive assessment of disease heterogeneity and has the potential to identify patients in whom HER2-targeted drugs can have a clinical benefit.
|
|
4. |
|
|
5. |
|
|
6. |
- Bjurling-Sjöberg, Petronella, 1968-, et al.
(author)
-
Resilient performance in healthcare during the COVID-19 pandemic (ResCOV) : study protocol for a multilevel grounded theory study on adaptations, working conditions, ethics and patient safety.
- 2021
-
In: BMJ Open. - : BMJ. - 2044-6055. ; 11:12
-
Journal article (peer-reviewed)abstract
- INTRODUCTION: Since early 2020, the COVID-19 pandemic has challenged societies and revealed the built-in fragility and dependencies in complex adaptive systems, such as healthcare. The pandemic has placed healthcare providers and systems under unprecedented amounts of strain with potential consequences that have not yet been fully elucidated. This multilevel project aims to explore resilient performance with the purpose of improving the understanding of how healthcare has adapted during the pandemic's rampage, the processes involved and the consequences on working conditions, ethics and patient safety.METHODS: An emerging explorative multilevel design based on grounded theory methodology is applied. Open and theoretical sampling is performed. Empirical data are gathered over time from written narratives and qualitative interviews with staff with different positions in healthcare organisations in two Swedish regions. The participants' first-person stories are complemented with data from the healthcare organisations' internal documents and national and international official documents.ANALYSIS: Experiences and expressions of resilient performance at different system levels and times, existing influencing risk and success factors at the microlevels, mesolevels and macrolevels and inter-relationships and consequences in different healthcare contexts, are explored using constant comparative analysis. Finally, the data are complemented with the current literature to develop a substantive theory of resilient performance during the pandemic.ETHICS AND DISSEMINATION: This project is ethically approved and recognises the ongoing strain on the healthcare system when gathering data. The ongoing pandemic provides unique possibilities to study system-wide adaptive capacity across different system levels and times, which can create an important basis for designing interventions focusing on preparedness to manage current and future challenges in healthcare. Feedback is provided to the settings to enable pressing improvements. The findings will also be disseminated through scientific journals and conferences.
|
|
7. |
- Ericsson, Olle, et al.
(author)
-
Clinical validation of a novel automated cell-free DNA screening assay for trisomies 21, 13, and 18 in maternal plasma.
- 2019
-
In: Prenatal diagnosis. - : Wiley. - 1097-0223 .- 0197-3851. ; 39:11, s. 1011-1015
-
Journal article (peer-reviewed)abstract
- To evaluate clinical performance of a new automated cell-free (cf)DNA assay in maternal plasma screening for trisomies 21, 18, and 13, and to determine fetal sex.Maternal plasma samples from 1200 singleton pregnancies were analyzed with a new non-sequencing cfDNA method, which is based on imaging and counting specific chromosome targets. Reference outcomes were determined by either cytogenetic testing, of amniotic fluid or chorionic villi, or clinical examination of neonates.The samples examined included 158 fetal aneuploidies. Sensitivity was 100% (112/112) for trisomy 21, 89% (32/36) for trisomy 18, and 100% (10/10) for trisomy 13. The respective specificities were 100%, 99.5%, and 99.9%. There were five first pass failures (0.4%), all in unaffected pregnancies. Sex classification was performed on 979 of the samples and 99.6% (975/979) provided a concordant result.The new automated cfDNA assay has high sensitivity and specificity for trisomies 21, 18, and 13 and accurate classification of fetal sex, while maintaining a low failure rate. The study demonstrated that cfDNA testing can be simplified and automated to reduce cost and thereby enabling wider population-based screening.
|
|
8. |
|
|
9. |
- Göras, Camilla, 1969-, et al.
(author)
-
From Threatening Chaos to Temporary Order through a Complex Process of Adaptation : A Grounded Theory Study of the Escalation of Intensive Care during the COVID-19 Pandemic.
- 2023
-
In: International Journal of Environmental Research and Public Health. - : MDPI. - 1661-7827 .- 1660-4601. ; 20:21
-
Journal article (peer-reviewed)abstract
- To ensure high-quality care, operationalize resilience and fill the knowledge gap regarding how to improve the prerequisites for resilient performance, it is necessary to understand how adaptive capacity unfolds in practice. The main aim of this research was to explain the escalation process of intensive care during the first wave of the pandemic from a microlevel perspective, including expressions of resilient performance, intervening conditions at the micro-meso-macrolevels and short- and long-term consequences. A secondary aim was to provide recommendations regarding how to optimize the prerequisites for resilient performance in intensive care. A grounded theory methodology was used. First-person stories from different healthcare professionals (n70) in two Swedish regions were analyzed using the constant comparative method. This resulted in a novel conceptual model (including 6 main categories and 24 subcategories), and 41 recommendations. The conclusion of these findings is that the escalation of intensive care can be conceptualized as a transition from threatening chaos to temporary order through a complex process of adaptation. To prepare for the future, the components of space, stuff, staff, system and science, with associated continuity plans, must be implemented, anchored and communicated to actors at all levels of the system.
|
|
10. |
- Hilner, Emelie, et al.
(author)
-
Direct Atomic Scale Imaging of III-V Nanowire Surfaces.
- 2008
-
In: Nano Letters. - : American Chemical Society (ACS). - 1530-6992 .- 1530-6984. ; 8:11, s. 3978-3982
-
Journal article (peer-reviewed)abstract
- We have succeeded in direct atomic scale imaging of the exterior surfaces of III-V nanowires by scanning tunneling microscopy (STM). By using atomic hydrogen, we expose the crystalline surfaces of InAs nanowires with regular InP segments in vacuum while retaining the wire morphology. We show images with atomic resolution of the two major types of InAs wurtzite nanowire surface facets and scanning tunneling spectroscopy (STS) data. Ab initio calculations of the lowest energy surface structures and simulated STM images, agree very well with experiments.
|
|