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Aside from graph neural networks (GNNs) attracting significant attention as a powerful framework revolutionizing graph representation learning, there has been an increasing demand for explaining GNN models. Although various explanation methods for GNNs have been developed, most studies have focused on instance-level explanations, which produce explanations tailored to a given graph instance. In our study, we propose Prototype-bAsed GNN-Explainer ([Formula: see text]), a novel model-level GNN explanation method that explains what the underlying GNN model has learned for graph classification by discovering human-interpretable prototype graphs. Our method produces explanations for a given class, thus being capable of offering more concise and comprehensive explanations than those of instance-level explanations. First, [Formula: see text] selects embeddings of class-discriminative input graphs on the graph-level embedding space after clustering them. Then, [Formula: see text] discovers a common subgraph pattern by iteratively searching for high matching node tuples using node-level embeddings via a prototype scoring function, thereby yielding a prototype graph as our explanation. Using six graph classification datasets, we demonstrate that [Formula: see text] qualitatively and quantitatively outperforms the state-of-the-art model-level explanation method. We also carry out systematic experimental studies by demonstrating the relationship between [Formula: see text] and instance-level explanation methods, the robustness of [Formula: see text] to input data scarce environments, and the computational efficiency of the proposed prototype scoring function in [Formula: see text].

Introduction : Distinguishing benign from malignant biliary strictures remains challenging despite diagnostic advancements. Follicular cholangitis, a rare benign condition, presents with symptoms and imaging similar to malignancies like cholangiocarcinoma, often complicating diagnosis, particularly when tumor markers are elevated and imaging suggests metastasis. Case presentation : A 57-year-old woman with hypertension and diabetes was admitted with jaundice. Elevated bilirubin and liver enzymes alongside high carbohydrate antigen 19-9 (CA19-9) levels but normal carcinoembryonic antigen (CEA) were noted. Imaging showed thickening from the hilar duct to the proximal common bile duct, accompanied by suspected lymph node metastases. Comprehensive ERCP-guided biopsies found no malignancy. Surgical resection led to a diagnosis of follicular cholangitis. Conclusions : Follicular cholangitis' long-term prognosis is elusive due to its rarity, and preoperative diagnosis is challenging. Increased awareness may improve diagnostic and treatment approaches, as this case adds to the disease's understanding.

Background: Clopidogrel monotherapy improved clinical outcomes compared with aspirin monotherapy during a chronic maintenance period in patients who underwent coronary stenting in the HOST-EXAM (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Extended Antiplatelet Monotherapy) trial. However, it is uncertain whether the beneficial effect of clopidogrel over aspirin is different according to the renal function., Methods and Results: We conducted a post hoc analysis of the HOST-EXAM trial. Chronic kidney disease (CKD) was defined as baseline estimated glomerular filtration rate <60 mL/min per 1.73 m 2 . The primary end point was a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission due to acute coronary syndrome, and Bleeding Academic Research Consortium bleeding type ≥3, during the 2-year follow up. Among the 5438 patients enrolled in the HOST-EXAM trial, 4844 patients (mean age, 63.3±10.6 years; 74.9% men) with a baseline creatinine value were analyzed in this study. A total of 508 (10.5%) patients had CKD, who were at higher risk of the primary end point compared with those without CKD (hazard ratio [HR], 2.01 [95% CI, 1.51-2.67]). Clopidogrel monotherapy was associated with a lower rate of the primary end point in both patients with CKD (HR, 0.74 [95% CI, 0.44-1.25]) and patients without CKD (HR, 0.71 [95% CI, 0.56-0.91]). No significant interaction was observed between the treatment effect and CKD status ( P for interaction=0.889)., Conclusions: During the chronic maintenance period after coronary stenting, the risk of thrombotic and bleeding events was significantly higher in patients with CKD compared with those without CKD. There was no statistical difference in the treatment effect of clopidogrel monotherapy in those with versus without CKD.

Purpose: The evolution of splenomegaly in patients with liver cirrhosis remains largely unknown. In this study, we followed the changes in splenic volume and established the natural course of splenomegaly. We developed an electronic circuit that simulated splenoportal circulation and identified the underlying hemodynamic mechanisms., Materials and Methods: This retrospective observational study included 93 patients with cirrhosis. Splenic volumes were measured in imaging studies at 6-month intervals and normalized by the ratio of each patient's maximum volume during follow-up (%Vmax). An electronic simulation model was constructed using software and realized on a breadboard., Results: Overall, the %Vmax increased from 0.77 ​± ​0.21 to a maximum of 1.00 ​± ​0.00 (p ​< ​0.001) during a median follow-up of 23 (3-162) months and then decreased to 0.84 ​± ​0.18 (p ​< ​0.001) during the next 9 (3-132) months. No interventional radiology procedure was performed to improve hepatic fibrosis and portal hypertension. The evolution of %Vmax showed single-peaked symmetry. An electronic simulation model showed that the upslope of the evolution curve was dependent on the increased intrahepatic vascular resistance and portal hypertension, whereas the downslope was dependent on the decreased portosystemic shunt (PSS) resistance., Conclusions: Splenomegaly in cirrhotic patients aggravated over a period of 23 months and then regressed spontaneously to its initial volume. Electronic simulation of splenoportal circulation showed that splenic enlargement was due to the advancement of liver cirrhosis and portal hypertension, whereas its regression was due to the development of a PSS., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Objective: Advancements in microsurgical technique and technology continue to improve outcomes in patients with skull base tumor. The primary cranial nerve eight monitoring systems used in hearing preservation surgery for vestibular schwannomas (VSs) are direct cranial nerve eight monitoring (DCNEM) and auditory brainstem response (ABR), although current guidelines are unable to definitively recommend one over the other due to limited literature on the topic. Thus, further research is needed to determine the utility of DCNEM and ABR. The authors performed a retrospective cohort study and created an interactive model that compares hearing preservation outcomes based on tumor size in patients receiving ABR+DCNEM and ABR-only monitoring., Methods: Twenty-eight patients received ABR+DCNEM and 72 patients received ABR-only monitoring during VS hearing preservation surgery at a single tertiary academic medical center between January 2008 and November 2022. Inclusion criteria consisted of adult patients with a preoperative American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) hearing classification of A or B. Tumor size was measured as the maximal medial to lateral length, including the internal auditory canal component., Results: Overall hearing preservation (word recognition score [WRS] > 0%) was achieved in 31 patients with ABR-only monitoring (43.1%) and in 18 patients with ABR+DCNEM (64.3%). Serviceable hearing preservation (AAO-HNS class A or B) was attained in 19 patients with ABR-only monitoring (26.4%) and in 11 patients with ABR+DCNEM (39.3%). There was no difference in overall hearing preservation between the two groups (p = 0.13). Change in tumor size was not associated with the odds of serviceable hearing preservation for the ABR-only group (p = 0.89); however, for ABR+DCNEM, there was some indication of an interaction between tumor size and the association of ABR+DCNEM versus ABR-only monitoring, with the odds of serviceable hearing preservation at p = 0.089. Furthermore, with ABR+DCNEM, every 0.5-cm increase in tumor size was associated with a decreased odds of serviceable hearing preservation on multivariable analysis (p = 0.05). For both overall and serviceable hearing preservation, a worse preoperative AAO-HNS classification was associated with a decreased odds of preservation (OR 0.43, 95% CI 0.19-0.97, p = 0.042; OR 0.17, 95% CI 0.053-0.55, p = 0.0031, respectively)., Conclusions: The result of this interactive model study proposes that there may be a higher chance of hearing preservation when using ABR+DCNEM rather than ABR alone for smaller tumors, with that relationship reversing as tumor size increases.

Background: Polypharmacy is a global public health concern. This study aimed to determine the prevalence of polypharmacy and trends in the use of commonly used and potentially inappropriate medications among older Korean patients., Methods: Individuals aged ≥ 65 years who were prescribed any medication between 2014 and 2018 were selected from the Korean National Health Information Database. Joinpoint regression analyses were used to determine trends in the age-adjusted polypharmacy rates by age group. The prescription rates of the most commonly used medications and the most commonly used potentially inappropriate medications were analysed by year or age group for patients with polypharmacy using the chi-square and proportion difference tests., Results: This study included 1,849,968 patients, 661,206 (35.7%) of whom had polypharmacy. Age-adjusted polypharmacy rates increased significantly between 2014 and 2018 (P = 0.046). Among patients with polypharmacy, the most commonly prescribed medications were aspirin (100 mg), atorvastatin, metformin, glimepiride, and rosuvastatin. The most commonly prescribed and potentially inappropriate medications were alprazolam, diazepam, amitriptyline, zolpidem, and dimenhydrinate. There was a significant decrease in the prescription rates for each of these drugs in 2018 compared with 2014 among patients with polypharmacy (all P < 0.001), whereas there was a significant increase in alprazolam prescription among patients aged ≥ 85 years when analysed by age group (P < 0.001)., Conclusions: This study revealed an increasing prevalence of polypharmacy among older adults. Additionally, it highlighted that the utilisation of commonly prescribed potentially inappropriate medications, such as benzodiazepines and tricyclic antidepressants, has remained persistent, particularly among patients aged ≥ 85 years who practiced polypharmacy. These findings provide evidence-based guidance for the development of robust polypharmacy management strategies to ensure medication safety among older adults., (© 2024. The Author(s).)