Detection and characterization of the hepatitis C virus

The term hepatitis literally means 'inflammation of the liver', Hepatitis can be caused by toxic substances. metabolic disorders or viral infections. Most clinical hepatitis cases have a viral etiology. Viral hepatitis appears to be an ancient disease (Deinhardt, 1991) and has been recognized as infectious since centuries. Evaluation of hepatitis outbreaks led to the hypothesis that more than one type of viral hepatitis existed. Initially, two different forms of viral infectious agents were identified (Krugman et aI., 1962, 1967). Hepatitis A virus (HA V) is orally transntitted and bas a short incubation period. The hepatitis B virus (HBV) is transntitred parenterally and has a long incubation period. HA V contains a single stranded RNA genome and belongs to the Picornaviridae, whereas the Hepatitis B virus (HBV) contains a partially double stranded DNA genome and is classified as a Hepadnavirus (Tiollais et aI., 1985). In the early 1980s, an RNA virus designated as hepatitis Delta (Rizetto, 1983) was recognized. This defective hepatotropic virus requires helper functions provided by HBV or another Hepadnavirus (Wang et aI., 1986). After the discovery of hepatitis A and B viruses as etiological agents for viral hepatitis, sensitive serologic assays were developed to diagnose the presence of these viruses

Design and Implementation of Signed Executables for Linux

We describe the design and implementation of signed executables for Linux, which provide the following strong integrity guarantees: the inability to tamper with executables and the inability to add new unauthorized executables. Unlike other implementations, ours covers statically and dynamically linked executables as well as executable scripts. In addition, we reduced the overhead of signature verification to almost zero by caching the successful verification results. The negligible overhead enables signature verification to be used as a basic building block for other applications of which some are described in this paper. Also UMIACS-TR-2001-4

Sequence analysis of the 5' untranslated region in isolates of at least four genotypes of hepatitis C virus in The Netherlands

The RNAs of hepatitis C virus (HCV) isolates from 62 patients with chronic HCV infection were analyzed by direct sequencing of the 5' untranslated region. Two important sequence motifs were recognized: one between positions -170 and -155 and the other between positions -132 and -117. These motifs are partly complementary. All three previously published genotypes were observed; 34 (55%) isolates were classified as type 1 (including prototype [from the United States] and HCV-BK [from Japan] sequences), 11 (18%) were classified as type 2 (including HC-J6 and HC-J8), and 12 (19%) were classified as type 3 (including EB1); one patient was infected with genotypes 1 and 2. Four (6%) isolates showed aberrant sequences and were therefore provisionally classified as genotype 4. These results indicate the significance of sequence variation among the 5' untranslated regions of different HCV genotypes and indicate that this region could possibly be used for consistent genotyping of HCV isolates

Outcome of ovarian cancer after breast cancer in BRCA1 and BRCA2 mutation carriers

Background:It is unknown whether a history of breast cancer (BC) affects the outcome of BRCA1/2-associated epithelial ovarian cancer (EOC). This was investigated in the current analysis.Methods:We included 386 BRCA1/2-associated EOC patients diagnosed between 1980 and 2015. Progression-free survival (PFS), progression-free interval (PFI), overall survival (OS) and ovarian cancer-specific survival (OCSS) were compared between EOC patients with and without previous BC.Results:BRCA-associated EOC patients with, vs without, a BC history had a significantly worse PFS and PFI (multivariate hazard ratio (HR mult) 1.47; 95% confidence interval (CI) 1.03-2.08 and HR mult 1.43; 95% CI 1.01-2.03), and a non-significantly worse OS (HR mult 1.15; 95% CI 0.84-1.57) and OCSS (HR mult 1.18; 95% CI 0.85-1.62). Ovarian cancer-specific survival was significantly worse for the subgroup treated with adjuvant chemotherapy for BC (HR mult 1.99; 95% CI 1.21-3.31).Conclusions:Our results suggest that BRCA1/2-associated EOC patients with a previous BC have a worse outcome than EOC patients without BC, especially when treated with adjuvant chemotherapy

Outcome of ovarian cancer after breast cancer in BRCA1 and BRCA2 mutation carriers

Background: It is unknown whether a history of breast cancer (BC) affects the outcome of BRCA1/2-associated epithelial ovarian cancer (EOC). This was investigated in the current analysis. Methods: We included 386 BRCA1/2-associated EOC patients diagnosed between 1980 and 2015. Progression-free survival (PFS), progression-free interval (PFI), overall survival (OS) and ovarian cancer-specific survival (OCSS) were compared between EOC patients with and without previous BC. Results: BRCA-associated EOC patients with, vs without, a BC history had a significantly worse PFS and PFI (multivariate hazard ratio (HRmult) 1.47; 95% confidence interval (CI) 1.03-2.08 and HRmult 1.43; 95% CI 1.01-2.03), and a non-significantly worse OS (HRmult 1.15; 95% CI 0.84-1.57) and OCSS (HRmult 1.18; 95% CI 0.85-1.62). Ovarian cancer-specific survival was significantly worse for the subgroup treated with adjuvant chemotherapy for BC (HRmult 1.99; 95% CI 1.21-3.31). Conclusions: Our results suggest that BRCA1/2-associated EOC patients with a previous BC have a worse outcome than EOC patients without BC, especially when treated with adjuvant chemotherapy

EXTERNALLY VERIFIABLE

Using hardware- and software-based techniques to realize a primitive Cfor externally verifiable code execution. omputing devices are routinely targeted by a wide variety of malware, such as spyware, trojans, rootkits, and viruses. The presence of exploitable vulnerabilities in system software, and the widespread availability of tools for constructing exploit code, has reduced the amount of effort required for attackers to introduce malware into computing devices. Increasing levels of network connectivity further exacerbates the problem of malware propagation by enabling attacks to be launched remotely. Current computing devices are routinely used for security-sensitive applications; thus malware present on these devices can potentially compromise the privacy and safety of users. Furthermore, most computing devices today are part of a large networked infrastructure. Hence, the compromise of any one computing device can lead to the compromise of the networked applications. For example, a rogu

FlexRTS: An extensible Orca run-time system

FlexRTS is a dynamically configurable and extensible run-time system for Orca, a high performance parallel programming system. It provides run-time and application programmers with full control over the implementation and placement of kernel and user-level modules (device drivers, protocol stacks, thread packages, etc.). This allows programmers to optimize the run-time system on a per application basis and take most leverage out of the available hardware. Keywords: operating systems, run-time systems, parallel programming, extensibility. 1. Introduction It is hard for an application programmer to take full advantage of existing hardware. This is largely caused by a lack of control over the available abstractions. Many researchers have interpreted this as kernel abstractions and have proposed mechanisms for extending or adapting these [4, 5, 8, 11, 14]. Non-kernel abstractions, e.g. those provided by a run-time system, are in theory easy to adapt and extend, but in practice they are j..

Bind: A fine-grained attestation service for secure distributed systems

In this paper, we propose BIND (Binding Instructions aNd Data), 1 a fine-grained attestation service for securing distributed systems. Code attestation has recently received considerable attention in trusted computing. However, current code attestation technology is relatively immature. First, due to the great variability in software versions and configurations, verification of the hash is difficult. Second, the time-of-use and time-of-attestation discrepancy remains to be addressed, since the code may be correct at the time of the attestation, but it may be compromised by the time of use. The goal of BIND is to address these issues and make code attestation more usable in securing distributed systems. BIND offers the following properties: 1) BIND performs fine-grained attestation. Instead of attesting to the entire memory content, BIND attests only to the piece of code we are concerned about. This greatly simplifies verification. 2) BIND narrows the gap between time-ofattestation and time-of-use. BIND measures a piece of code immediately before it is executed and uses a sand-boxing mechanism to protect the execution of the attested code. 3) BIND ties the code attestation with the data that the code produces, such that we can pinpoint what code has been run to generate that data. In addition, by incorporating the verification of input data integrity into the attestation, BIND offers transitive integrity verification, i.e., through one signature, we can vouch for the entire chain of processes that have performed transformations over a piece of data. BIND offers a general solution toward establishing a trusted environment for distributed system designers