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Help me, Doctor AI? A cross-national experiment on the effects of disease threat and stigma on AI health information-seeking intentions
Get PDFGenerative AI chatbots are emerging as novel sources for health information. Adopting a cross-national perspective, this study examines how disease-related factors—namely, disease threat and stigma—influence both individuals' intentions to seek health information via generative AI and their preferences for AI compared to traditional interpersonal sources like doctors and peers. In a preregistered 2x2 online experiment, participants from Austria, Denmark, France, and Serbia (Ntotal = 1951) encountered written scenarios about their health that manipulated disease threat (low vs. high) and stigma (low vs. high). The sample was stratified to ensure representativeness for age, gender, and educational level across the countries studied. Results showed no main effect of disease threat on AI information-seeking intentions, but stigma significantly influenced preferences, particularly in mild health conditions. Participants were more likely to consult AI over peers for stigmatized conditions, highlighting the role of AI's anonymous interface in reducing social judgment. Country differences further revealed that national contexts also shape AI adoption: while participants in Denmark and France showed a stronger preference for AI over peers, those in Serbia and Austria preferred peers over AI. Additionally, AI trust and literacy emerged as the strongest predictors of both AI usage intentions and preferences. These findings indicate that gen AI tools can play a complementary role in the health information ecosystem, particularly for stigmatized conditions and in contexts where traditional sources are perceived as less accessible or judgment-free
Amalgam alternatives: Susceptibility of novel self-adhesive materials to changes in dentin mineralization
No full textObjectives: This study explores the effects of artificial de- and hypermineralization on the shear bond strength (SBS) of three innovative dental materials: a modern ion – releasing resin–based composite (Cention Forte (CF)), a resin-modified glass ionomer cement (Surefil One (SO)), and a high-viscosity glass ionomer cement (Equia Forte (EF)), all tested on human dentin. Methods: A total of 360 human dentin specimens were divided into 18 groups (n = 20). Each material was bonded to either healthy, hypermineralized, or demineralized dentin. After aging at 37 °C in distilled water for 1 week and artificial saliva for 6 months, SBS was tested following ISO 29,022. Fracture origins and patterns were analyzed via light microscopy. Results: The SBS values of EF on hyper- and demineralized dentin were lower after 1 week and 6 months when compared to sound dentin, whereas for CF this trend was only seen on demineralized dentin after 1 week. Regardless of aging, the SBS values of SO displayed no significant difference in comparison to the reference. Across all substrates and aging types, the SBS values of CF were the highest. The long-term bond reliability of CF and EF on sound dentin was similar, as was the bond reliability of CF and SO on hypermineralized dentin. Conclusions: CF produces the strongest bond to dentin irrespective of dentin substrate or aging. Demineralization deteriorates the bond strength of both CF and EF, whereas hypermineralization only that of EF. SO remains unaffected by changes in dentin mineralization, enabling it to form stronger bonds to hypermineralized dentin than EF. Clinical Significance: A proper assessment of a material's bond strength to dentin substrates with varying degrees of mineralization is crucial for evaluating its potential as an effective amalgam replacement, capable of forming reliable bonds across a broad range of tooth substrate
Invasive therapies for Parkinson’s disease: an adapted excerpt from the guidelines of the German Society of Neurology
Get PDFBackground: Parkinson’s disease (PD) is characterized by hypokinetic motor symptoms, tremor, and various non-motor symptoms with frequent fluctuations of symptoms in advanced disease stages. Invasive therapies, such as deep brain stimulation (DBS), ablative therapies, and continuous subcutaneous or intrajejunal delivery of dopaminergic drugs via pump therapies are available for the management of this complex motor symptomatology and may also impact non-motor symptoms. The recent update of the clinical guideline on PD by the German Neurological Society (Deutsche Gesellschaft für Neurologie e.V.; DGN) offers clear guidance on the indications and applications of these treatment options.
Methods: The guideline committee formulated diagnostic questions for invasive therapies and structured them according to the PICOS framework (Population–Intervention–Comparisons–Outcome–Studies). A systematic literature review was conducted. Questions were addressed using the findings from the literature review and consented by the guideline committee.
Results: Specific recommendations are given regarding (i) the optimal timing for starting invasive therapies, (ii) the application of DBS, (iii) the use of pump therapies in advanced PD, (iv) the indications for ablative procedures, and (iv) selecting the most appropriate therapy according to individual patient characteristics.
Conclusion: This review is an adapted excerpt of the chapters on the use of invasive therapies in PD of the novel German guideline on PD. Clear recommendations on the use of treatment options for advanced PD are provided
γ-Secretase modulator resistance of an aggressive Alzheimer-causing presenilin mutant can be overcome in the heterozygous patient state by a set of advanced compounds
Get PDFBackground: Amyloid-β peptide (Aβ) species of 42 or 43 amino acids in length (Aβ42/43) trigger Alzheimer´s disease (AD) and are produced in abnormal amounts by mutants of the γ-secretase subunit presenilin-1 (PS1), which represent the primary cause of familial AD (FAD). Lowering these peptides by γ-secretase modulators (GSMs) is increasingly considered a safe strategy to treat AD since these compounds do not affect the overall cleavage of γ-secretase substrates. GSMs were shown to modulate not only wild-type (WT) γ-secretase but also FAD mutants, expanding their potential use also to the familial form of the disease. Unlike most other FAD mutants, the very aggressive PS1 L166P mutant is largely resistant to GSMs. However, these data were mostly obtained from overexpression models, which mimic more the less relevant homozygous state rather than the heterozygous patient situation.
Methods: Mouse embryonic fibroblast and induced pluripotent stem cell-derived neuronal PS1 L166P knock-in (KI) cell models were treated with various GSMs and Aβ responses were assessed by immunoassays and/or gel-based analysis.
Results: We identified GSMs that lower Aβ42 and/or Aβ43 when PS1 L166P is heterozygous, as it is the case in affected patients, and could reduce the amount of pathogenic Aβ species towards WT levels. RO7019009 was the most potent of these compounds, reducing both pathogenic species and concomitantly increasing the short Aβ37 and Aβ38, of which the latter has been associated with delayed AD progression. Another effective compound, the structurally novel indole-type GSM RO5254601 specifically acts on the Aβ42 product line leading to a selective increase of the beneficial Aβ38. Interestingly, we further found that this class of GSMs can bind not only one, but both presenilin fragments suggesting that it targets γ-secretase at an unusual binding site.
Conclusion: Our data show that even highly refractory presenilin FAD mutants are in principle tractable with GSMs extending the possibilities for potential clinical studies in FAD with suitable GSM molecules
A Basic Approach to Equations of States for Studying the Real Behavior of Noble Gases
Get PDFThe relation between the pressure and molar concentration (in mol/L) of real gases in a low- to medium-pressure range is precisely described by a logarithmic two-parameter equation. Increasing the concentration caused an increase in pressure and also the weakening of the effect due to intermolecular interactions, forming the basis for an equation with an adjusted parameter. Exceeding a critical concentration by a further increase caused a switch to another set of parameters in the same equation. At high pressure, a second switch to an exponential term was observed. This equation of state, defined segment by segment, was attributed to three different structures of the medium. The validity of the equations found was verified with experimental data reported in the literature for helium, neon, argon, krypton, and xenon and is discussed in more detail for argon. The temperature dependence of the parameters of the equations is reported and the formation of a liquid phase is discussed
Antiresorptive therapy in combination with radiation results in enhanced risk for necrosis and associated complications
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Patients exposed to a combination of antiresorptive medication and radiotherapy of the head and neck area developing necrosis of the jaw in the course of treatment are extremely rare. Therefore, the aim of this study was to identify the outcome and complications in this highly vulnerable patient cohort.
Study Design
Seventeen patients who received both antiresorptive treatment and radiotherapy (medication-related osteonecrosis of the jaw/osteoradionecrosis = the [MRONJ/ORN] group) in the head and neck area were enrolled in this study. Included patients were treated in our department between 2005 and 2022. Four hundred twenty-four patients with MRONJ (the MRONJ group) and 138 patients with ORN of the jaw were enrolled as two control groups (the ORN group). Demographic data, lesion localization, date of primary diagnosis, clinical symptoms, type of therapy (surgical or non-surgical), details on antiresorptive treatment, outcome, and complications were recorded.
Results
Pathological fractures, continuity resection, and recurrence appear more often in patients who receive a combination of antiresorptive treatment and radiotherapy in the head and neck area compared with patients undergoing only one of these treatments. There was a statistically significant difference (P < .001) between the MRONJ/ORN group and the MRONJ group and the MRONJ/ORN group and the ORN group considering recurrence, fracture, and continuity resection. Patients with ORN combined with MRONJ have a 4-times higher risk for developing recurrence compared with patients with MRONJ and a 1.5-times higher risk for recurrence compared with patients with ORN. Jaw fracture and continuity resection appear more often in patients with MRONJ/ORN.
Conclusions
Patients under antiresorptive therapy in combination with radiation therapy in the head and neck area have a higher risk for developing complications in case of osteonecrosis of the jaw. Therefore, a strict follow-up care schedule is highly recommended
Diagnostic features in paediatric MDS‐EB with UBTF‐internal tandem duplication: defining a unique subgroup
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Tandem-duplications of the UBTF gene (UBTF-TDs) have recently been identified as a new genetic driver in young individuals with acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS). Disease in these newly defined subgroups is characterized by poor response to standard intensive chemotherapy and inferior survival of the affected patients. However, a thorough analysis of bone marrow histomorphology of UBTF-mutated neoplasia has not been undertaken thus far.
Methods and results:
In this retrospective study, we investigated the characteristic histopathological features of a cohort comprising 14 paediatric MDS patients with an excess of blasts (MDS-EB) and UBTF-TD. Bone marrow biopsies from these patients revealed hypercellularity and severe dysplasia across all three haematopoietic lineages. In particular, a marked hyperplastic megakaryopoiesis characterized by the presence of frequent micromegakaryocytes and a high number of monolobulated cells forming small clusters was observed. Additionally, erythropoiesis was left-shifted, with numerous blastoid precursors. The granulopoietic precursors displayed prominent UBTF-positive nucleoli.
Conclusion:
The unique combination of these histomorphological features strongly suggests a possible UBTF aberration. It will allow initiating the appropriate genetic testing to confirm the presence of UBTF-TD and identify potential additional genetic alterations. Such molecular profiling will not only contribute to a better understanding of the disease mechanism, but also facilitate more rational treatment approaches for these high-risk paediatric MDS patients