Stargazer: Long-Term and Multiregional Measurement of Timing/ Geolocation-Based Cloaking

Malicious hosts have come to play a significant and varied role in today's cyber attacks. Some of these hosts are equipped with a technique called cloaking, which discriminates between access from potential victims and others and then returns malicious content only to potential victims. This is a serious threat because it can evade detection by security vendors and researchers and cause serious damage. As such, cloaking is being extensively investigated, especially for phishing sites. We are currently engaged in a long-term cloaking study of a broader range of threats. In the present study, we implemented Stargazer, which actively monitors malicious hosts and detects geographic and temporal cloaking, and collected 30,359,410 observations between November 2019 and February 2022 for 18,397 targets from 13 sites where our sensors are installed. Our analysis confirmed that cloaking techniques are widely abused, i.e., not only in the context of specific threats such as phishing. This includes geographic and time-based cloaking, which is difficult to detect with single-site or one-shot observations. Furthermore, we found that malicious hosts that perform cloaking include those that survive for relatively long periods of time, and those whose contents are not present in VirusTotal. This suggests that it is not easy to observe and analyze the cloaking malicious hosts with existing technologies. The results of this study have deepened our understanding of various types of cloaking, including geographic and temporal ones, and will help in the development of future cloaking detection methods

Prognostic value of metastin expression in human pancreatic cancer

<p>Abstract</p> <p>Background</p> <p><it>KiSS-1 </it>was identified as a metastasis-suppressing gene in melanoma cells. The <it>KiSS-1 </it>gene product (metastin) was isolated from human placenta as the ligand of GPR54, a G-protein-coupled receptor. The role of metastin and GPR54 in tumor progression is not fully understood.</p> <p>Methods</p> <p>We investigated the clinical significance of metastin and GPR54 expression in pancreatic cancer. We evaluated immunohistochemical expression of metastin and GPR54 in pancreatic ductal adenocarcinoma tissues obtained from 53 consecutive patients who underwent resection between July 2003 and May 2007 at Kyoto University Hospital. In 23 consecutive patients, the plasma metastin level was measured before surgery by enzyme immunoassay.</p> <p>Results</p> <p>Strong immunohistochemical expression of metastin was detected in 13 tumors (24.5%), while strong expression of GPR54 was detected in 30 tumors (56.6%). Tumors that were negative for both metastin and GPR54 expression were significantly larger than tumors that were positive for either metastin or GPR54 (p = 0.047). Recurrence was less frequent in patients who had metastin-positive tumors compared with those who had metastin-negative tumors (38.5% versus 70.0%, p = 0.04). Strong expression of metastin and GPR54 was significantly correlated with longer survival (p = 0.02). Metastin expression by pancreatic cancer was an independent prognostic factor for longer survival (hazard ratio, 2.1; 95% confidence interval, 1.1–4.7; p = 0.03), and the patients with a high plasma metastin level (n = 6) did not die after surgical resection.</p> <p>Conclusion</p> <p>Strong expression of metastin and GPR54 by pancreatic cancer is associated with longer survival. Metastin expression is an independent prognostic factor for the survival of pancreatic cancer patients. The plasma metastin level could become a noninvasive prognostic factor for the assessment of pancreatic cancer.</p

Detection of Peer-to-Peer Nodes based on Query Routing

In this paper, we propose a novel P2P node detection method by analyzing network traffic and extracting packets which contain query messages. Most previous methods detect P2P nodes by using signatures of known applications or taking advantages of traffic features in P2P nodes. However, they cannot detect hosts running unknown P2P applications while keeping low false positive rate. To address the problem, we focus on the resource discovery mechanism where query messages are routed and transmitted through several nodes to locate hosts providing certain files. Then, we attempt to detect hosts that appear to receive and transmit queries with other hosts. To do so, our approach monitors the traffic of targets and searches for pairs of inbound/outbound packets which are likely to contain same queries by computing their similarities. Through evaluation experiments with two popular P2P based file sharing software, LimeWire and Winny, we show this approach detects P2P nodes within a few hundreds of seconds with a few false alerts in a week.APSIPA ASC 2009: Asia-Pacific Signal and Information Processing Association, 2009 Annual Summit and Conference. 4-7 October 2009. Sapporo, Japan. Oral session: Signal Processing and Security in Communications (5 October 2009)

Clinical diagnosis of type I allergy by means of SPR imaging with less than a microliter of peripheral blood

The identification of antigen that induces activation of mast cells and basophils by crosslinking IgE bound to the cell surface is crucial to avoid symptoms of allergic diseases. Surface plasmon resonance imaging (SPRI) possesses a great potential for clinical diagnosis of allergy, in that it reveals living cell activation following the binding of antigens to IgE, on real-time and single cell basis without artificial labeling. However, present technique of SPRI requires freshly isolated basophils of patients and cannot analyze multiple samples in parallel. To overcome such problems, we developed devices for SPRI to make a broad observation area and a multi-well SPRI sensor chip with a hydrophobic membrane. The employment of human IgE receptor-expressing mast cell lines (RBL-48 cells) sensitized with serum, collected and stored from less than a microliter of patient’s blood, allowed us to detect specific reactions of RBL-48 cells in response to antigens. This technique may be a useful tool as a high throughput screening system of type I allergy not only for freshly prepared basophils but also for sera stored in clinical practices