| 1. |
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- 2019
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Tidskriftsartikel (refereegranskat)
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| 2. |
- Baum, R. P., et al.
(författare)
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First-in-Humans Application of Tb-161: A Feasibility Study Using Tb-161-DOTATOC
- 2021
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Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 2159-662X. ; 62:10, s. 1391-1397
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Tidskriftsartikel (refereegranskat)abstract
- Tb-161 has decay properties similar to those of Lu-177 but, additionally, emits a substantial number of conversion and Auger electrons. The aim of this study was to apply Tb-161 in a clinical setting and to investigate the feasibility of visualizing the physiologic and tumor biodistributions of Tb-161-DOTATOC. Methods: Tb-161 was shipped from Paul Scherrer Institute, Villigen-PSI, Switzerland, to Zentralklinik Bad Berka, Bad Berka, Germany, where it was used for the radiolabeling of DOTATOC. In 2 separate studies, 596 and 1,300 MBq of Tb-161-DOTATOC were administered to a 35-y-old male patient with a metastatic, well-differentiated, nonfunctional malignant paraganglioma and a 70-y-old male patient with a metastatic, functional neuroendocrine neoplasm of the pancreatic tail, respectively. Whole-body planar g-scintigraphy images were acquired over a period of several days for dosimetry calculations. SPECT/CT images were reconstructed using a recently established protocol and visually analyzed. Patients were observed for adverse events after the application of Tb-161-DOTATOC. Results: The radiolabeling of DOTATOC with Tb-161 was readily achieved with a high radiochemical purity suitable for patient application. Planar images and dosimetry provided the expected time-dependent biodistribution of Tb-161-DOTATOC in the liver, kidneys, spleen, and urinary bladder. SPECT/CT images were of high quality and visualized even small metastases in bones and liver. The application of Tb-161-DOTATOC was well tolerated, and no related adverse events were reported. Conclusion: This study demonstrated the feasibility of imaging even small metastases after the injection of relatively low activities of Tb-161-DOTATOC using g-scintigraphy and SPECT/CT. On the basis of this essential first step in translating Tb-161 to clinics, further efforts will be directed toward the application of Tb-161 for therapeutic purposes.
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| 3. |
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| 4. |
- Lestinsky, M., et al.
(författare)
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Physics book: CRYRING@ESR
- 2016
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Ingår i: European Physical Journal: Special Topics. - : Springer Science and Business Media LLC. - 1951-6401 .- 1951-6355. ; 225:5, s. 797-882
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Forskningsöversikt (refereegranskat)abstract
- The exploration of the unique properties of stored and cooled beams of highly-charged ions as provided by heavy-ion storage rings has opened novel and fascinating research opportunities in the realm of atomic and nuclear physics research. Since the late 1980s, pioneering work has been performed at the CRYRING at Stockholm (Abrahamsson et al. 1993) and at the Test Storage Ring (TSR) at Heidelberg (Baumann et al. 1988). For the heaviest ions in the highest charge-states, a real quantum jump was achieved in the early 1990s by the commissioning of the Experimental Storage Ring (ESR) at GSI Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt (Franzke 1987) where challenging experiments on the electron dynamics in the strong field regime as well as nuclear physics studies on exotic nuclei and at the borderline to atomic physics were performed. Meanwhile also at Lanzhou a heavy-ion storage ring has been taken in operation, exploiting the unique research opportunities in particular for medium-heavy ions and exotic nuclei (Xia et al. 2002).
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| 5. |
- Levin, Johannes, et al.
(författare)
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α-Synuclein seed amplification assay detects Lewy body co-pathology in autosomal dominant Alzheimer's disease late in the disease course and dependent on Lewy pathology burden
- 2024
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Ingår i: Alzheimer's and Dementia. - 1552-5260.
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Amyloid beta and tau pathology are the hallmarks of sporadic Alzheimer's disease (AD) and autosomal dominant AD (ADAD). However, Lewy body pathology (LBP) is found in ≈ 50% of AD and ADAD brains. METHODS: Using an α-synuclein seed amplification assay (SAA) in cerebrospinal fluid (CSF) from asymptomatic (n = 26) and symptomatic (n = 27) ADAD mutation carriers, including 12 with known neuropathology, we investigated the timing of occurrence and prevalence of SAA positive reactivity in ADAD in vivo. RESULTS: No asymptomatic participant and only 11% (3/27) of the symptomatic patients tested SAA positive. Neuropathology revealed LBP in 10/12 cases, primarily affecting the amygdala or the olfactory areas. In the latter group, only the individual with diffuse LBP reaching the neocortex showed α-synuclein seeding activity in CSF in vivo. DISCUSSION: Results suggest that in ADAD LBP occurs later than AD pathology and often as amygdala- or olfactory-predominant LBP, for which CSF α-synuclein SAA has low sensitivity. Highlights: Cerebrospinal fluid (CSF) real-time quaking-induced conversion (RT-QuIC) detects misfolded α-synuclein in ≈ 10% of symptomatic autosomal dominant Alzheimer's disease (ADAD) patients. CSF RT-QuIC does not detect α-synuclein seeding activity in asymptomatic mutation carriers. Lewy body pathology (LBP) in ADAD mainly occurs as olfactory only or amygdala-predominant variants. LBP develops late in the disease course in ADAD. CSF α-synuclein RT-QuIC has low sensitivity for focal, low-burden LBP.
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| 6. |
- Marin, Ida, et al.
(författare)
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Establishment of a clinical SPECT/CT protocol for imaging of(161)Tb
- 2020
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Ingår i: Ejnmmi Physics. - : Springer Science and Business Media LLC. - 2197-7364. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Background It has been proposed, and preclinically demonstrated, that(161)Tb is a better alternative to(177)Lu for the treatment of small prostate cancer lesions due to its high emission of low-energy electrons.Tb-161 also emits photons suitable for single-photon emission computed tomography (SPECT) imaging. This study aims to establish a SPECT protocol for(161)Tb imaging in the clinic. Materials and methods Optimal settings using various gamma-camera collimators and energy windows were explored by imaging a Jaszczak phantom, including hollow-sphere inserts, filled with(161)Tb. The collimators examined were extended low-energy general purpose (ELEGP), medium-energy general purpose (MEGP), and low-energy high resolution (LEHR), respectively. In addition, three ordered subset expectation maximization (OSEM) algorithms were investigated: attenuation-corrected OSEM (A-OSEM); attenuation and dual- or triple-energy window scatter-corrected OSEM (AS-OSEM); and attenuation, scatter, and collimator-detector response-corrected OSEM (ASC-OSEM), where the latter utilized Monte Carlo-based reconstruction. Uniformity corrections, using intrinsic and extrinsic correction maps, were also investigated. Image quality was assessed by estimated recovery coefficients (RC), noise, and signal-to-noise ratio (SNR). Sensitivity was determined using a circular flat phantom. Results The best RC and SNR were obtained at an energy window between 67.1 and 82.1 keV. Ring artifacts, caused by non-uniformity, were removed with extrinsic uniformity correction for the energy window between 67.1 and 82.1 keV, but not with intrinsic correction. Analyzing the lower energy window between 48.9 and 62.9 keV, the ring artifacts remained after uniformity corrections. The recovery was similar for the different collimators when using a specific OSEM reconstruction. Recovery and SNR were highest for ASC-OSEM, followed by AS-OSEM and A-OSEM. When using the optimized parameter setting, the resolution of(161)Tb was higher than for(177)Lu (8.4 +/- 0.7 vs. 10.4 +/- 0.6 mm, respectively). The sensitivities for(161)Tb and(177)Lu were 7.41 and 8.46 cps/MBq, respectively. Conclusion SPECT with high resolution is feasible with(161)Tb; however, extrinsic uniformity correction is recommended to avoid ring artifacts. The LEHR collimator was the best choice of the three tested to obtain a high-resolution image. Due to the complex emission spectrum of low-energy photons, window-based scatter correction had a minor impact on the image quality compared to using attenuation correction only. On the other hand, performing attenuation, scatter, and collimator-detector correction clearly improved image quality. Based on these data, SPECT-based dosimetry for(161)Tb-labeled radiopharmaceuticals is feasible.
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| 7. |
- Mathey, Carina M, et al.
(författare)
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Molecular Genetic Screening in Patients With ACE Inhibitor/Angiotensin Receptor Blocker-Induced Angioedema to Explore the Role of Hereditary Angioedema Genes
- 2022
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Ingår i: Frontiers in Genetics. - : Frontiers Media S.A.. - 1664-8021. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Angioedema is a relatively rare but potentially life-threatening adverse reaction to angiotensin-converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARBs). As with hereditary forms of angioedema (HAE), this adverse reaction is mediated by bradykinin. Research suggests that ACEi/ARB-induced angioedema has a multifactorial etiology. In addition, recent case reports suggest that some ACEi/ARB-induced angioedema patients may carry pathogenic HAE variants. The aim of the present study was to investigate the possible association between ACEi/ARB-induced angioedema and HAE genes via systematic molecular genetic screening in a large cohort of ACEi/ARB-induced angioedema cases. Targeted re-sequencing of five HAE-associated genes (SERPING1, F12, PLG, ANGPT1, and KNG1) was performed in 212 ACEi/ARB-induced angioedema patients recruited in Germany/Austria, Sweden, and Denmark, and in 352 controls from a German cohort. Among patients, none of the identified variants represented a known pathogenic variant for HAE. Moreover, no significant association with ACEi/ARB-induced angioedema was found for any of the identified common [minor allele frequency (MAF) >5%] or rare (MAF < 5%) variants. However, several non-significant trends suggestive of possible protective effects were observed. The lowest p-value for an individual variant was found in PLG (rs4252129, p.R523W, p = 0.057, p.adjust > 0.999, Fisher's exact test). Variant p.R523W was found exclusively in controls and has previously been associated with decreased levels of plasminogen, a precursor of plasmin which is part of a pathway directly involved in bradykinin production. In addition, rare, potentially functional variants (MAF < 5%, Phred-scaled combined annotation dependent depletion score >10) showed a nominally significant enrichment in controls both: 1) across all five genes; and 2) in the F12 gene alone. However, these results did not withstand correction for multiple testing. In conclusion, our results suggest that HAE-associated mutations are, at best, a rare cause of ACEi/ARB-induced angioedema. Furthermore, we were unable to identify a significant association between ACEi/ARB-induced angioedema and other variants in the investigated genes. Further studies with larger sample sizes are warranted to draw more definite conclusions concerning variants with limited effect sizes, including protective variants.
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| 8. |
- Muller, C., et al.
(författare)
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Promising Prospects for Sc-44-/Sc-47-Based Theragnostics: Application of Sc-47 for Radionuclide Tumor Therapy in Mice
- 2014
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Ingår i: Journal of Nuclear Medicine. - : Society of Nuclear Medicine. - 0161-5505 .- 2159-662X. ; 55:10, s. 1658-1664
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, Sc-47 has attracted attention because of its favorable decay characteristics (half-life, 3.35 d; average energy, 162 key; Ey, 159 key) for therapeutic application and for SPECT imaging. The aim of the present study was to investigate the suitability of Sc-47 for radionuclide therapy in a preclinical setting. For this purpose a novel DOTA-folate conjugate (cm10) with an albumin-binding entity was used. Methods: Sc-47 was produced via the Ca-46(n,gamma)Ca-47 -> Sc beta-47 nuclear reaction at the high-flux reactor at the Institut Laue-Langevin. Separation of the Sc-47 from the target material was performed by a semi-automated process using extraction chromatography and cation exchange chromatography. Sc-47-labeled cm10 was tested on folate receptor-positive KB tumor cells in vitro. Biodistribution and SPECT imaging experiments were performed in KB tumor-bearing mice. Radionuclide therapy was conducted with two groups of mice, which received either Sc-47-cm10 (10 MBq) or only saline. Tumor growth and survival time were compared between the two groups of mice. Results: Irradiation of Ca-46 resulted in approximately 1.8 GBq of Ca-47, which subsequently decayed to Sc-47. Separation of Sc-47 from Ca-47 was obtained with 80% yield in only 10 min. The Sc-47 was then available in a small volume (-500 pL) of an ammonium acetate/HCI (pH 4.5) solution suitable for direct radiolabeling. Sc-47-cm10 was prepared with a radiochemical yield of more than 96% at a specific activity of up to 13 MBq/nmol. In vitro 475ccm10 showed folate receptor-specific binding and uptake into KB tumor cells. In vivo SPECT/CT images allowed the visualization of accumulated radioactivity in KB tumors and in the kidneys. The therapy study showed a significantly delayed tumor growth in mice, which received Sc-47-cm10 (10 MBq, 10 Gy) resulting in a more than 50% increase in survival time, compared with untreated control mice. Conclusion: With this study, we demonstrated the suitability of using Sc-47 for therapeutic purposes. On the basis of our recent results obtained with Sc-44-folate, the present work confirms the applicability of Sc-44/Sc-47 as an excellent matched pair of nuclides for PET imaging and radionuclide therapy.
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| 9. |
- Muller, C., et al.
(författare)
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Terbium-161 for PSMA-targeted radionuclide therapy of prostate cancer
- 2019
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Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - : Springer Science and Business Media LLC. - 1619-7070 .- 1619-7089. ; 46:9, s. 1919-1930
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Tidskriftsartikel (refereegranskat)abstract
- PurposeThe prostate-specific membrane antigen (PSMA) has emerged as an interesting target for radionuclide therapy of metastasized castration-resistant prostate cancer (mCRPC). The aim of this study was to investigate Tb-161 (T-1/2=6.89days; E beta(?)(av)=154keV) in combination with PSMA-617 as a potentially more effective therapeutic alternative to Lu-177-PSMA-617, due to the abundant co-emission of conversion and Auger electrons, resulting in an improved absorbed dose profile.Methods(161)Tb was used for the radiolabeling of PSMA-617 at high specific activities up to 100MBq/nmol. Tb-161-PSMA-617 was tested in vitro and in tumor-bearing mice to confirm equal properties, as previously determined for Lu-177-PSMA-617. The effects of Tb-161-PSMA-617 and Lu-177-PSMA-617 on cell viability (MTT assay) and survival (clonogenic assay) were compared in vitro using PSMA-positive PC-3 PIP tumor cells. Tb-161-PSMA-617 was further investigated in therapy studies using PC-3 PIP tumor-bearing mice.Results(161)Tb-PSMA-617 and Lu-177-PSMA-617 displayed equal in-vitro properties and tissue distribution profiles in tumor-bearing mice. The viability and survival of PC-3 PIP tumor cells were more reduced when exposed to Tb-161-PSMA-617 as compared to the effect obtained with the same activities of Lu-177-PSMA-617 over the whole investigated concentration range. Treatment of mice with Tb-161-PSMA-617 (5.0MBq/mouse and 10MBq/mouse, respectively) resulted in an activity-dependent increase of the median survival (36 vs 65days) compared to untreated control animals (19days). Therapy studies to compare the effects of Tb-161-PSMA-617 and Lu-177-PSMA-617 indicated the anticipated superiority of Tb-161 over Lu-177.Conclusion(161)Tb-PSMA-617 showed superior in-vitro and in-vivo results as compared to Lu-177-PSMA-617, confirming theoretical dose calculations that indicate an additive therapeutic effect of conversion and Auger electrons in the case of Tb-161. These data warrant more preclinical research for in-depth investigations of the proposed concept, and present a basis for future clinical translation of Tb-161-PSMA-617 for the treatment of mCRPC.
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| 10. |
- Schmitz, G. J., et al.
(författare)
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Software Solutions for ICME
- 2016
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Ingår i: JOM. - : Springer. - 1047-4838 .- 1543-1851. ; 68:1, s. 70-76
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Tidskriftsartikel (refereegranskat)abstract
- The Integrated Computational Materials Engineering expert group (ICMEg), a coordination activity of the European Commission, aims at developing a global and open standard for information exchange between the heterogeneous varieties of numerous simulation tools. The ICMEg consortium coordinates respective developments by a strategy of networking stakeholders in the first International Workshop on Software Solutions for ICME, compiling identified and relevant software tools into the Handbook of Software Solutions for ICME, discussing strategies for interoperability between different software tools during a second (planned) international workshop, and eventually proposing a scheme for standardized information exchange in a future book or document. The present article summarizes these respective actions to provide the ICME community with some additional insights and resources from which to help move this field forward.
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