Graph Anomaly Detection with Graph Neural Networks: Current Status and Challenges

Graphs are used widely to model complex systems, and detecting anomalies in a graph is an important task in the analysis of complex systems. Graph anomalies are patterns in a graph that do not conform to normal patterns expected of the attributes and/or structures of the graph. In recent years, graph neural networks (GNNs) have been studied extensively and have successfully performed difficult machine learning tasks in node classification, link prediction, and graph classification thanks to the highly expressive capability via message passing in effectively learning graph representations. To solve the graph anomaly detection problem, GNN-based methods leverage information about the graph attributes (or features) and/or structures to learn to score anomalies appropriately. In this survey, we review the recent advances made in detecting graph anomalies using GNN models. Specifically, we summarize GNN-based methods according to the graph type (i.e., static and dynamic), the anomaly type (i.e., node, edge, subgraph, and whole graph), and the network architecture (e.g., graph autoencoder, graph convolutional network). To the best of our knowledge, this survey is the first comprehensive review of graph anomaly detection methods based on GNNs.Comment: 9 pages, 2 figures, 1 tables; to appear in the IEEE Access (Please cite our journal version.

Cardiac Angiosarcoma on the Right Atrium: Two Cases

We detected two cases of right atrial angiosarcoma that had a similar appearance on imaging studies. Although the surgical findings were similar for the two patients, one had a clear resection margin, while the other had tumor cells in the resection margin on frozen biopsy. We suggest that preoperative data on magnetic resonance imaging and computed tomography in patients with angiosarcomas may not predict the exact extent of surgical resection or prognostic outcomes

The Relationship between Aldosterone to Renin Ratio and RI Value of the Uterine Artery in the Preeclamptic Patient vs. Normal Pregnancy

aldosterone are increased during normal pregnancy. However, these values in preeclampsia are decreased to nearly that of a nonpregnant subject, and vascular sensitivity to angiotensin II is increased. In preeclampsia, aldosterone is decreased less than rennin. Therefore current studies were undertaken to determine the relationship between aldosterone to renin ratio (ARR) and uterine artery perfusion via RI value. Materials and Methods: In this study, the relationship between plasma aldosterone and renin concentration was determined in 27 preeclamptic women and 50 normal pregnant women, whose gestational weeks were matched. The aldosterone to renin ratio was calculated and compared between the two groups. Doppler velocimetry of the uterine artery, which was used to calculate resistance index (RI), was performed on all subjects. The relationship between ARR and RI value was reviewed

Uterine Artery Doppler Velocimetry During Mid-second Trimester to Predict Complications of Pregnancy Based on Unilateral or Bilateral Abnormalities

We performed this study to evaluate uterine artery Doppler velocimetry (UADV) measurement of unilateral or bilateral abnormalities as a predictor of complications in pregnancy during the mid-second trimester (20-24 weeks). We enrolled 1,090 pregnant women who had undergone UADV twice: once between the 20th and 24th week (1st stage) and again between the 28th and 32nd week (2nd stage) of pregnancy, and then delivered at Yonsei Medical Center. UADV was performed bilaterally. Follow-up UADV was performed between the 28th and 32nd week, and the frequencies of pregnancy-induced hypertension (PIH), fetal growth restriction (FGR), and preterm delivery (before 34 weeks of gestation) were determined. Chi-squared and t-tests were used where appropriate, with p < .05 considered significant. According to the results of UADV performed between 20-24 weeks of gestation, 825 women (75.7%) were included in the normal group, 196 (18.0%) in the unilateral abnormality group, and 69 (6.3%) in the bilateral abnormality group. The incidences of FGR were 8.0%, 10.2%, and 26.1%, and the incidences of PIH were 0.1%, 3.6%, and 14.5%, respectively. The incidence of PIH was significantly lower in the normal group. The incidences of preterm delivery were 2.2%, 5.6%, and 8.7%, respectively. PIH developed in 46.7% of patients with bilateral abnormal findings in both the 1st and 2nd stage tests, and developed in none of the patients with normal findings in both tests. Abnormal results found by UADV performed between the 20-24th weeks of pregnancy, such as high S/D ratios regardless of placental location and the presence of an early diastolic notch, were associated with significant increases in the incidences of intrauterine growth restriction (IUGR) and PIH. This was true for both bilateral and unilateral abnormalities. Abnormal findings in bilateral UADV during the second trimester especially warrant close follow up for the detection of subsequent development of pregnancy complications

Increased expression of cysteine cathepsins in ovarian tissue from chickens with ovarian cancer

<p>Abstract</p> <p>Background</p> <p>Cysteine cathepsins (CTSs) are involved in the degradation and remodeling of the extracellular matrix and are associated with cell transformation, differentiation, motility, and adhesion. These functions are also related to cancer cell invasion and metastasis. Chickens spontaneously develop epithelial ovarian cancer and are therefore a good animal model for human ovarian cancer. However, no studies have investigated the expression of CTSs in chickens with ovarian cancer.</p> <p>Methods</p> <p>Cancerous (n = 5) and normal (n = 3) ovaries were collected from 2-to 3-year-old hens, and ovarian tissue samples were collected for study. Ovarian cancers were evaluated with hematoxylin and eosin staining. Reverse transcriptase and quantitative PCR analyses, in situ hybridization analysis were performed to examine the mRNA expression pattern of three CTSs in detail, and protein expression of CTSB was evaluated.</p> <p>Results</p> <p>The CTSB, CTSC, and CTSS genes were highly expressed in cancerous chicken ovaries. Messenger RNAs for the three CTSs were localized to a nodule area, a major characteristic of cancerous ovaries, but the three CTSs showed no specific localization in normal ovaries. Immunoreactive CTSB protein was present in the nodule area of cancerous ovaries.</p> <p>Conclusion</p> <p>Our results suggest that CTSB, CTSC, and CTSS have important functions in the development of epithelial ovarian cancer.</p

Early Recurring Hepatocellular Carcinoma after Partial Hepatic Resection: Preoperative CT Findings

OBJECTIVE: The purpose of this study was to determine the utility of preoperative CT in predicting early recurrence of hepatocellular carcinoma after partial hepatic resection. MATERIALS AND METHODS: Preoperative three-phase helical CT scans in 53 patients with hepatocellular carcinoma were retrospectively reviewed by two radiologists. In 27 patients (group I), HCC had recurred within six months, while 26 (group II) had remained disease free for at least two years. In each group, preoperative CT findings were evaluated in each group for the tumor size and number, the presence or absence of capsule, distinctness of tumor margin, perinodular extension, and the presence or absence of portal vein thrombosis. RESULTS: In group I, a tumor capsule of tumor was seen in five of 27 patients (19%), and in group II, in 16 of 26 (62%) (p =.001). The tumor margin was distinct in eight patients (30%) in group I and in 20 (77%) in group II (p =.001). Multiple tumors, perinodular extension, and portal vein thrombosis were more frequently seen in group I but the differences were not statistically significant (p >.05). Tumor size was similar in each group (p >.05). CONCLUSION: Preoperative CT findings that may help predict the early recurrence of hepatocellular carcinoma after surgical resection are an absence of capsule of tumors and an indistinct margin. Reference to these findings during preoperative CT can guide clinicians in their choice of treatment.ope

Treatment of Branch Retinal Artery Occlusion With Transluminal Nd:YAG Laser Embolysis

The purpose of this paper was to report a successful treatment of transluminal Nd:YAG laser embolysis (NYE) for branch retinal artery occlusion (BRAO) with visible emboli. Two patients with acute, severe vision loss secondary to a branch retinal artery occlusion with visible emboli in one eye underwent NYE. A complete ocular examination was performed which included biomicroscopy of the posterior pole of the retina, intraocular pressure measurement, fundus color photographs, and fluorescein angiography (FA). After the NYE, the two patients showed dramatic improvements in best-corrected visual acuity, as well as, immediate and dramatic restorations in flow past the obstructed arteriole in FA. NYE is a treatment modality to be considered in patients with BRAO who present acutely with severe vision loss and a visible embolus

Report of a Korean Patient with Cystic Fibrosis, Carrying Q98R and Q220X Mutations in the CFTR Gene

Although cystic fibrosis (CF) is one of the most frequently seen autosomal-recessive disorders in Caucasians, it is extremely rare in the Korean population. Recently, a 15-yr-old Korean boy was admitted to our hospital complaining of coughing, sputum, and exertional dyspnea. Chest radiographs and computed tomographic chest and paranasal sinus scans revealed diffuse bronchiectasis and pansinusitis. Pulmonary function tests revealed severe obstructive impairment. The average sweat chloride concentrations on both of the patients' forearms were 63.0 mM/L (reference limit: <40 mM/L). Upon mutation analysis, two different mutations (Q98R and Q220X) were identified in the cystic fibrosis transmembrane conductance regulator gene, both of which had been previously detected in CF patients, one from France and the other from England. As CF is quite rare in Korea, the diagnosis of CF in this patient might be delayed. Therefore, we recommend that a diagnosis of CF should be suspected in patients exhibiting unexplained chronic respiratory symptoms

Pseudoaneurysm of the popliteal artery mimicking tumorous condition

Diagnosing pseudoaneurysms of the popliteal artery is usually straightforward in physical examinations and imaging findings. However, when a pseudoaneurysm shows a soft tissue mass with adjacent osseous change, it can mimic a bone tumor or a soft tissue sarcoma. We present a case of a 65-year-old man who had a pseudoaneurysm of the popliteal artery showing soft tissue mass and insinuating into the intramedullary cavity of the tibia. This presented case emphasizes the importance of considering pseudoaneurysms in the differential diagnosis of an apparent soft tissue mass with pressure erosion in adjacent bone