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This work investigates the proposed enhanced efficacy of photodynamic therapy (PDT) by activating photosensitizers (PSs) with Cherenkov light (CL). The approaches of Yoon et al. to test the effect of CL with external radiation were taken up and refined. The results were used to transfer the applied scheme from external radiation therapy to radionuclide therapy in nuclear medicine. Here, the CL for the activation of the PSs (psoralen and trioxsalen) is generated by the ionizing radiation from rhenium-188 (a high-energy beta-emitter, Re-188). In vitro cell survival studies were performed on FaDu, B16 and 4T1 cells. A characterization of the PSs (absorbance measurement and gel electrophoresis) and the CL produced by Re-188 (luminescence measurement) was performed as well as a comparison of clonogenic assays with and without PSs. The methods of Yoon et al. were reproduced with a beam line at our facility to validate their results. In our studies with different concentrations of PS and considering the negative controls without PS, the statements of Yoon et al. regarding the positive effect of CL could not be confirmed. There are slight differences in survival fractions, but they are not significant when considering the differences in the controls. Gel electrophoresis showed a dominance of trioxsalen over psoralen in conclusion of single and double strand breaks in plasmid DNA, suggesting a superiority of trioxsalen as a PS (when irradiated with UVA). In addition, absorption measurements showed that these PSs do not need to be shielded from ambient light during the experiment. An observational test setup for a PDT nuclear medicine approach was found. The CL spectrum of Re-188 was measured. Fluctuating inconclusive results from clonogenic assays were found.

Background: The administration of a 166 Ho scout dose is available as an alternative to 99m Tc particles for pre-treatment imaging in Selective Internal Radiation Therapy (SIRT). It has been reported that the 166 Ho scout dose may be more accurate for the prediction of microsphere distribution and the associated therapy planning. The aim of the current study is to compare the scintigraphic imaging characteristics of both isotopes, considering the objectives of the pre-treatment imaging using clinically geared phantoms., Methods: Planar and SPECT/CT images were obtained using a NEMA image quality phantom in different phantom setups and another body-shaped phantom with several inserts. The influence of collimator type, count statistics, dead time effects, isotope properties and patient obesity on spatial resolution, contrast recovery and the detectability of small activity accumulations was investigated. Furthermore, the effects of the imaging characteristics on personalized dosimetry are discussed., Results: The images with 99m Tc showed up to 3 mm better spatial resolution, up to two times higher contrast recovery and significantly lower image noise than those with 166 Ho. The contrast-to-noise ratio was up to five times higher for 99m Tc than for 166 Ho. Only when using 99m Tc all activity-filled spheres could be distinguished from the activity-filled background. The measurements mimicking an obese patient resulted in a degraded image quality for both isotopes., Conclusions: Our measurements demonstrate better scintigraphic imaging properties for 99m Tc compared to 166 Ho in terms of spatial resolution, contrast recovery, image noise, and lesion detectability. While the 166 Ho scout dose promises better prediction of the microsphere distribution, it is important to consider the inferior imaging characteristics of 166 Ho, which may affect individualized treatment planning in SIRT., (© 2024. The Author(s).)

The use of radionuclides for targeted endoradiotherapy is a rapidly growing field in oncology. In particular, the focus on the biological effects of different radiation qualities is an important factor in understanding and implementing new therapies. Together with the combined approach of imaging and therapy, therapeutic nuclear medicine has recently made great progress. A particular area of research is the use of alpha-emitting radionuclides, which have unique physical properties associated with outstanding advantages, e.g., for single tumor cell targeting. Here, recent results and open questions regarding the production of alpha-emitting isotopes as well as their chemical combination with carrier molecules and clinical experience from compassionate use reports and clinical trials are discussed.

Complex 3D-shaped optics are difficult to coat with conventional technologies. In this research, large top-open optical glass cubes with a 100 mm side length were functionalized to simulate large dome-shaped optics. Antireflection coatings for the visible range (420-670 nm) and for a single wavelength (550 nm) were applied by atomic layer deposition simultaneously on two and six demonstrators, respectively. Reflectance measurements on both the inner and outer glass surfaces confirm a conformal AR coating with a residual reflectance significantly below 0.3% for visible wavelengths and 0.2% for single wavelengths on nearly the entire surface of the cubes.

Background: A long duration of untreated illness (DUI) is an unfavorable prognostic factor in anorexia nervosa (AN) and is associated with chronic illness progression. Although previous preventive measures aimed at reducing DUI and thus improving short- and long-term treatment outcomes have been partially successful, a better understanding of the factors involved in the sensitive phase prior to treatment initiation is needed. To date, there is no validated instrument available to assess these factors specifically for patients with AN. The FABIANA-project (Facilitators and barriers in anorexia nervosa treatment initiation) aims at identifying predictors of the DUI in order to target preventive measures better in the future. As part of this project, the FABIANA-checklist was developed, based on a multi-informant perspective and a multimodal bottom-up approach. The present study focusses on the process of item generation, item selection and psychometric validation of the checklist., Methods: Based upon a previous qualitative study, an initial set of 73 items was generated for the most frequently mentioned facilitators and barriers of treatment initiation in AN. After a process of consensual rating and cognitive pre-testing, the resulting 25-item version of the FABIANA-checklist was provided to a sample of female patients (N = 75), aged ≥ 14 years with AN that underwent their first psychotherapeutic treatment in the last 12 months. After item analysis, dimensionality of the final version of the FABIANA-checklist was tested by Principal Component Analysis (PCA). We evaluated construct validity assuming correlations with related constructs, such as perceived social support (F-SozU), support in the health care system (PACIC-5A), illness perception and coping (BIPQ)., Results: We included 54 adult and 21 adolescent patients with AN, aged on average 21.4 years. Average BMI was 15.5 kg/m 2 , age of onset was 19.2 years and average DUI was 2.25 years. After item analysis, 7 items were excluded. The PCA of the 18-item-FABIANA-checklist yielded six components explaining 62.64% of the total variance. Overall internal consistency was acceptable (Cronbach's α = .76) and construct validity was satisfactory for 14 out of 18 items. Two consistent components emerged: "primary care perceived as supportive and competent" (23.33%) and "emotional and practical support from relatives" (9.98%). With regard to the other components, the heterogeneity of the items led to unsatisfactory internal consistency, single item loading and in part ambiguous interpretability., Conclusions: The FABIANA-checklist is a valid instrument to assess factors involved in the process of treatment initiation of patients with AN. Psychometrics and dimensionality testing suggests that experienced emotional and practical support from the primary health care system and close relatives are main components. The results indicate that a differentiated assessment at item level is appropriate. In order to quantify the relative importance of the factors and to derive recommendations on early-intervention approaches, the predictive effect of the FABIANA-items on the DUI will be determined in a subsequent study which will further include the perspective of relatives and primary caregivers. Trial registration Clinical Trials.gov Identifier: NCT03713541: https://clinicaltrials.gov/ct2/show/NCT03713541 ., (© 2021. The Author(s).)

Background: An early psychotherapeutic treatment of anorexia nervosa (AN) is crucial for a good prognosis. In order to improve treatment initiation, knowledge about facilitators and barriers to treatment is needed., Objective: Against this background, we aimed to identify facilitators and barriers from the perspectives of patients, carers and professionals using a qualitative approach., Method: To this end, semi-structured interviews were conducted in triads of female patients with AN aged 14 years and older at the beginning of their first psychotherapeutic treatment, their carers, and referring health care professionals. A modified Grounded Theory approach was used for analysis., Results: In total, 22 interviews were conducted (n = 6 adults, n = 4 adolescents, 4 full triads). The duration of untreated AN ranged between 30 days and 25.85 years (M = 3.06 ± 8.01 years). A wide spectrum of facilitators and barriers within the patient, the social environment, the health care system and the society were identified. Most prominent factors were 'recognizing and addressing' by close others, 'waiting times and availability' and 'recommendations and referrals' by health care professionals. 'Positive role models for treatment' were perceived as a specific facilitative social influence. Facilitators were more frequently mentioned than barriers and most of the factors seem to hold potential for modifiability., Conclusion: Overall, the findings suggest that early intervention approaches for AN should not only address patients and the health care system, but may also involve carers and successfully treated former patients., Trial Registration: ClinicalTrials.gov Identifier: NCT03713541 .

Background: Anorexia nervosa is a serious disorder, which often takes a chronic course. Early treatment leads to a significantly better prognosis and prevents chronicity. However, existing evidence on facilitators and barriers in anorexia nervosa treatment initiation is scarce., Aims: Against this background, the FABIANA study (ClinicalTrials.gov Identifier: NCT03713541) aims to (a) identify potentially modifiable facilitators and barriers from the perspectives of adolescent and adult patients with anorexia nervosa, carers and physicians, (b) develop and test an instrument for the combined assessment of multiple key facilitators and barriers, and (c) quantify the effect of potentially modifiable versus non-modifiable key facilitators and barriers on the duration of untreated illness (DUI) in patients with anorexia nervosa., Method: FABIANA is an observational, mixed-method-study divided into three consecutive substudies each corresponding to one of the study aims. All three substudies will include female patients with anorexia nervosa aged 14 years and older at the beginning of their first psychotherapeutic anorexia nervosa treatment. The qualitative substudy I and the quantitative substudy III will additionally include carers and involved physicians. The recruitment will take place at 20 cooperating study centres throughout Germany, which provide in-patient or out-patient anorexia nervosa specialist care. The DUI will be calculated based on the month of illness onset as determined in validated interviews on lifetime anorexia nervosa symptoms and the therapist-reported date of treatment initiation., Conclusions: Strengths and limitations of the retrospective assessment of the DUI will be discussed. The findings of the FABIANA study will contribute to the development of evidence-based early-intervention approaches and the prevention of a chronic course of illness., Trial Registration: ClinicalTrials.gov Identifier: NCT03713541., Declaration of Interest: None.

Objective: Knowing which specific verbal techniques "good" therapists use in their daily work is important for training and evaluation purposes. In order to systematize what is being practiced in the field, our aim was to empirically identify verbal techniques applied in psychodynamic sessions and to differentiate them according to their basic semantic features using a bottom-up, qualitative approach., Method: Mixed-Method-Design: In a comprehensive qualitative study, types of techniques were identified at the level of utterances based on transcribed psychodynamic therapy sessions using Qualitative Content Analysis (4211 utterances). The definitions of the identified categories were successively refined and modified until saturation was achieved. In a subsequent quantitative study, inter-rater reliability was assessed both at the level of utterances (n = 8717) and at the session level (n = 38). The convergent validity of the categories was investigated by analyzing associations with the Interpretive and Supportive Technique Scale (ISTS)., Results: The inductive approach resulted in a classification system with 37 categories (Psychodynamic Interventions List, PIL). According to their semantic content, the categories can be allocated to three dimensions: form (24 categories), thematic content (9) and temporal focus (4). Most categories showed good or excellent inter-rater reliability and expected associations with the ISTS were predominantly confirmed. The rare use of the residual category "Other" suggests that the identified categories might comprehensively describe the breadth of applied techniques., Conclusions: The atheoretical orientation and the clear focus on overt linguistic features should enable the PIL to be used without intensive training or prior theoretical knowledge. The PIL can be used to investigate the links between verbal techniques derived from practice and micro-outcomes (at the session level) as well as the overall therapeutic outcomes. This approach might enable us to determine to what extent the outcome of therapy is due to unintended or non-theoretically relevant techniques.