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conferenceseries.com
Volume 7, Issue 3 (Suppl) J Gastrointest Dig Syst, an open access journal
ISSN: 2161-069X Gastro 2017
June 12-13, 2017
June 12-13, 2017 Rome, Italy
11th Global
GastroenterologistsMeeting
J Gastrointest Dig Syst 2017, 7:3(Suppl)
DOI: 10.4172/2161-069X-C1-050
Computational analysis to detect resistance mutations to direct acting antivirals in hepatitis C virus
Karina Salvatierra
National University of Misiones, Argentina
Hepatitis C virus (HCV) infection is considered as a major public health problem with an estimate of 200 million people infected
worldwide. HCV infection is the major cause of chronic liver disease, with severe outcomes including cirrhosis and hepatocellular
carcinoma and it is the main cause of liver transplantation. The treatment for HCV chronic infection with pegylated interferon alpha
plus ribavirin inhibitors is unspecific; consequently, the treatment is effective in only 50% of patients infected. This has prompted the
development of direct-acting antivirals agents (DAA’s) that target virus proteins. Unfortunately, since the virus has a high replication
rate and its RNA polymerase lacks proofreading activity, genetic variations might produce resistance against the DAA’s. These DAA’s
have demonstrated a potent effect in vitro and in vivo; however, virus mutations associated with the development of resistance have
been described. The objective of this work is to detect mutations in known aminoacids to be implicated in resistance to DAA’s in
sequences obtained of conventional Sanger and cloning sequencing. We have designed and developed an online information system
named Biomedical Mutation Analysis (BMA), which allows users to calculate changes in nucleotide and amino acid sequences for
each selected sequence from conventional Sanger and cloning sequencing. BMA allows the computational analysis quickly, easily and
effectively. Furthermore, the development of different visualization techniques allows a proper interpretation and understanding of
the results. The data obtained from BMA will be useful for HCV resistance surveillance for the design of broad-range inhibitors and
rationale therapeutic regimen.
The role of contrast-enhanced ultrasound in the diagnosis of focal liver lesions
Katerina Busko
N.N. Petrov Research Institute of Oncology, Russia
Introduction: At present, differential diagnosis of focal liver lesions usually identified at computed tomography (CT) or magnetic
resonance imaging (MRI). The conventional ultrasound (US) offers no such comparable ability to characterize a focal liver lesion.
The appearance of malignant liver lesions in ultrasound B-mode are very variable: they can be hypoechoic, hyperechoic; they can
have a peripheral halo. For example, hemangioma and colorectal carcinoma metastases can be very similar and be hyperechoic in a
grayscale. New imaging method - contrast enhanced ultrasound (CEUS) with micro bubble contrast agents has improved the ability
of US to characterize a focal liver lesions. On CEUS, all liver malignant lesions can present a typical wash-out pattern in the portal
and late phases.
Aim: Aim of our study was to evaluate the diagnostic value of CEUS for the characterization of focal liver lesions.
Materials & Methods: This prospective study was carried out at the Petrov Research Institute of Oncology, Ministry of Health, Russia.
This study was approved by the institution review board at our institute and informed written consent was obtained from all of the
reviewed subjects. 119 patients underwent conventional ultrasound examination including standardized CEUS of a focal liver lesion
within our institute. The CEUS results were compared with the CT or MRI. Final diagnosis was based on histology.
Results: CEUS is more sensitive than conventional US for the detection of focal liver lesions. The efficacy of CEUS examination is
similar to that of contrast CT and MRI. CEUS may play a significant role in questionable diagnostic situations owing to its ability to
visualize characteristic features of different liver lesions therefore, helping to adequately plan the treatment strategy.
Conclusion: It should be noted that the high diagnostic potential of CEUS of focal liver lesions do not decrease the capabilities of the
other diagnostic methods (CT and MRI), and in particular cases can supplement them. Therefore, the role of CEUS, in our opinion,
should be limited to the use in difficult differential diagnostic cases.