4,532 research outputs found
Evaluating the Knowledge Base Completion Potential of GPT
Structured knowledge bases (KBs) are an asset for search engines and other
applications, but are inevitably incomplete. Language models (LMs) have been
proposed for unsupervised knowledge base completion (KBC), yet, their ability
to do this at scale and with high accuracy remains an open question. Prior
experimental studies mostly fall short because they only evaluate on popular
subjects, or sample already existing facts from KBs. In this work, we perform a
careful evaluation of GPT's potential to complete the largest public KB:
Wikidata. We find that, despite their size and capabilities, models like GPT-3,
ChatGPT and GPT-4 do not achieve fully convincing results on this task.
Nonetheless, they provide solid improvements over earlier approaches with
smaller LMs. In particular, we show that, with proper thresholding, GPT-3
enables to extend Wikidata by 27M facts at 90% precision.Comment: 12 pages 4 table
Static Magnetic Proximity Effect in Pt Layers on Sputter-Deposited NiFe2O4 and on Fe of Various Thicknesses Investigated by XRMR
The longitudinal spin Seebeck effect is detected in sputter-deposited NiFe2O4
films using Pt as a spin detector and compared to previously investigated
NiFe2O4 films prepared by chemical vapor deposition. Anomalous Nernst effects
induced by the magnetic proximity effect in Pt can be excluded for the
sputter-deposited NiFe2O4 films down to a certain limit, since x-ray resonant
magnetic reflectivity measurements show no magnetic response down to a limit of
0.04 {\mu}B per Pt atom comparable to the case of the chemicallydeposited
NiFe2O4 films. These differently prepared films have various thicknesses.
Therefore, we further studied Pt/Fe reference samples with various Fe
thicknesses and could confirm that the magnetic proximity effect is only
induced by the interface properties of the magnetic material.Comment: 4 pages, 4 figure
Identification of Seasonal Variations of Antibodies against PR-10-Specific Epitopes Can Be Improved Using Peptide-Phage Display
Background: In pollinosis patients, allergen-specific antibody titers show seasonal variations. Little is known about
these variations at the epitope level. Objectives: We aimed at
investigating seasonal variations on the level of allergen epitope recognition in patients with Bet v 1-related food allergy
using a peptide phage display approach. Methods: Serum
samples collected over 1 year from 4 patients of the placebo
arm of the birch-associated soya allergy immunotherapy trial
were included. To identify epitopes from Bet v 1-related food
allergens, patient sera were used in peptide phage display
experiments. In silico analysis of enriched allergen-related
motifs was performed. Results: We identified epitope motifs
related to Bet v 1 and its homologs in soya and hazelnut (Gly
m 4 and Cor a 1, respectively) that were enriched in accordance with birch and hazel pollen exposure. Within several
weeks after the birch pollen season peak, the pattern of identified epitope motifs differed considerably among patients.
Data for amino acid preferences in homologous Bet v 1 and
Cor a 1 epitope motifs identified for one of the investigated
patients suggest changes in concentration or specificity of
serum antibodies for the Cor a 1 epitope motif. Conclusions:
Peptide phage display data suggest an impact of birch and
hazel pollen exposure on the recognition pattern of Bet v
1-like allergen epitopes. Epitope-oriented analyses could
provide deeper, personalized details regarding the allergen
epitope recognition influenced by pollen exposure beyond
the capability of current method
In Vivo Mapping of Hippocampal Subfields in Mesial Temporal Lobe Epilepsy: Relation to Histopathology
Instructing human macrophage polarization by stiffness and glycosaminoglycan functionalization in 3D collagen networks
Dynamic alterations of composition and mechanics of the extracellular matrix (ECM) are suggested to modulate cellular behavior including plasticity of macrophages (MPhs) during wound healing. In this study, engineered 3D fibrillar matrices based on naturally occurring biopolymers (collagen I, glycosaminoglycans (GAGs)) were used to mimic matrix stiffening as well as modification by sulfated and non-sulfated GAGs at different stages of wound healing. Human MPhs were found to sensitively respond to these microenvironmental cues in terms of polarization towards pro-inflammatory or wound healing phenotypes over 6 days in vitro. MPhs exhibited a wound healing phenotype in stiffer matrices as determined by protein and gene expression of relevant cytokines (IL10, IL12, TNF). Presence of sulfated and non-sulfated GAGs inhibited this polarization effect. Furthermore, control experiments on 2D matrices stressed the relevance of using stiffness-controlled 3D matrices, as MPhs showed a reciprocal polarization behavior depending on GAG presence. Hence, the results indicate a strong influence of dimensionality, stiffness, and GAG presence of the biomaterial scaffold on MPh polarization and emphasize the need for matrices closely mimicking the 3D in vivo context with a variable stiffness and GAG composition in in vitro studies
Gastrointestinal Stromal Tumors: Clinical Symptoms, Location, Metastasis Formation, and Associated Malignancies in a Single Center Retrospective Study
Background and Aims: Gastrointestinal stromal tumors (GISTs) are rare malignancies but the most common mesenchymal tumors of the digestive tract. Recent advances in diagnostic imaging and an increasing incidence will confront us more frequently with stromal tumors. This single center study aimed to characterize GIST patients in terms of tumor location, clinical presentation, metastasis formation, as well as associated secondary malignancies. Methods: In a retrospective study, 104 patients with a histologically confirmed diagnosis of GIST, collected between 1993 and 2011, were characterized for several clinical features. Results: The most common GIST location was the stomach (67.6%) followed by the small intestine (16.2%). Gastrointestinal bleeding (55.8%) and abdominal pain (38.5%) were the most frequently reported symptoms whereas about one-third of patients remained clinically asymptomatic (31.6%); 14.4% of patients had either synchronous or metachronous metastases and there was a significant prevalence also in the low risk group. The proportion of secondary malignant associated neoplasms was 31% in our GIST cohort, among which gastrointestinal, genitourinary tumors, and breast cancer were the most prevalent. Conclusion: There was a considerable risk for metastasis formation and the development of secondary neoplasias that should encourage discussion about the appropriate surveillance strategy after surgery for GIST
Using Multiparametric Cardiac Magnetic Resonance to Phenotype and Differentiate Biopsy-Proven Chronic from Healed Myocarditis and Dilated Cardiomyopathy.
(1) Objectives: To discriminate biopsy-proven myocarditis (chronic vs. healed myocarditis) and to differentiate from dilated cardiomyopathy (DCM) using cardiac magnetic resonance (CMR). (2) Methods: A total of 259 consecutive patients (age 51 ± 15 years; 28% female) who underwent both endomyocardial biopsy (EMB) and CMR in the years 2008-2021 were evaluated. According to right-ventricular EMB results, patients were divided into either chronic (n = 130, 50%) or healed lymphocytic myocarditis (n = 60, 23%) or DCM (n = 69, 27%). The CMR protocol included functional, strain, and late gadolinium enhancement (LGE) imaging, T2w imaging, and T2 mapping. (3) Results: Left-ventricular ejection fraction (LV-EF) was higher, and the indexed end-diastolic volume (EDV) was lower in myocarditis patients (chronic: 42%, median 96 mL/m²; healed: 49%, 86 mL/m²) compared to the DCM patients (31%, 120 mL/m²), p < 0.0001. Strain analysis demonstrated lower contractility in DCM patients vs. myocarditis patients, p < 0.0001. Myocarditis patients demonstrated a higher LGE prevalence (68% chronic; 59% healed) than the DCM patients (45%), p = 0.01. Chronic myocarditis patients showed a higher myocardial edema prevalence and ratio (59%, median 1.3) than healed myocarditis (23%, 1.3) and DCM patients (13%, 1.0), p < 0.0001. T2 mapping revealed elevated values more frequently in chronic (90%) than in healed (21%) myocarditis and DCM (23%), p < 0.0001. T2 mapping yielded an AUC of 0.89 (sensitivity 90%, specificity 76%) in the discrimination of chronic from healed myocarditis and an AUC of 0.92 (sensitivity 86%, specificity 91%) in the discrimination of chronic myocarditis from DCM, both p < 0.0001. (4) Conclusions: Multiparametric CMR imaging, including functional parameters, LGE and T2 mapping, may allow differentiation of chronic from healed myocarditis and DCM and therefore help to optimize patient management in this clinical setting
Culturing of Melanocytes from the Equine Hair Follicle Outer Root Sheath
Hair follicles harbor a heterogeneous regenerative cell pool and represent a putative low-to-non-invasively available source of stem cells. We previously reported a technology for culturing human melanocytes from the hair follicle outer root sheath (ORS) for autologous pigmentation of tissue engineered skin equivalents. This study translated the ORS technology to horses. We de-veloped a culture of equine melanocytes from the ORS (eMORS) from equine forelock hair follicles cultured by means of an analogue human hair follicle-based in vitro methodology. The procedure was adjusted to equine physiology by addition of equine serum to the culture medium. The hair follicles were isolated by macerating forelock skin rests, enzymatically digested and subjected to air-medium-interface cultivation method. The procedure resulted in differentiated equine melanocytes, which exhibited typical morphology, presence of melanosomes, expression of cytoskeleton proteins vimentin, α-SMA, Sox2, S100ß and tyrosinase as well as tyrosinase activity followed by production of melanin. According to all assessed parameters, eMORS could be ranked as partially melanotic melanocytes. The results of the study offer an experimental base for further insight into hair follicle biology in equine and for comparative studies of hair follicles across different species
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