Noninvasive Biomarkers (noninvasive + biomarker)

Distribution by Scientific Domains

Selected Abstracts

Independent estimation of T*2 for water and fat for improved accuracy of fat quantification

Venkata V. Chebrolu
Abstract Noninvasive biomarkers of intracellular accumulation of fat within the liver (hepatic steatosis) are urgently needed for detection and quantitative grading of nonalcoholic fatty liver disease, the most common cause of chronic liver disease in the United States. Accurate quantification of fat with MRI is challenging due the presence of several confounding factors, including T*2 decay. The specific purpose of this work is to quantify the impact of T*2 decay and develop a multiexponential T*2 correction method for improved accuracy of fat quantification, relaxing assumptions made by previous T*2 correction methods. A modified Gauss-Newton algorithm is used to estimate the T*2 for water and fat independently. Improved quantification of fat is demonstrated, with independent estimation of T*2 for water and fat using phantom experiments. The tradeoffs in algorithm stability and accuracy between multiexponential and single exponential techniques are discussed. Magn Reson Med 63:849,857, 2010. 2010 Wiley-Liss, Inc. [source]

Serum cytokeratin-18 fragment level: A noninvasive biomarker for not only nonalcoholic steatohepatitis, but also alcoholic steatohepatitis,

HEPATOLOGY, Issue 5 2010
M.D., Xiaohua Li Ph.D.
No abstract is available for this article. [source]

Fecal calprotectin, lactoferrin, and endoscopic disease activity in monitoring anti-TNF-alpha therapy for Crohn's disease

Taina Sipponen MD
Abstract Background: Fecal calprotectin and lactoferrin are promising noninvasive biomarkers for intestinal inflammation. In Crohn's disease (CD), during anti-TNF-alpha (TNF-,) treatment, the clinical significance of these markers has, however, been insufficiently explored. Methods: Among CD patients receiving anti-TNF-, therapy we assessed the role of fecal calprotectin and lactoferrin as surrogate markers for mucosal healing. Before and 3 months after the beginning of anti-TNF-, induction, 15 patients underwent ileocolonoscopy with scoring of the Crohn's Disease Index of Severity (CDEIS). Fecal samples for calprotectin and for lactoferrin measurements were collected and the Crohn's Disease Activity Index (CDAI) was calculated at the time of the endoscopies and 2 and 8 weeks after the first treatment. Results: The median CDEIS fell from 13.0 to 4.8 (P = 0.002) and CDAI from 158 to 68 (P = 0.005). Accordingly, the median fecal calprotectin concentration fell from 1173 ,g/g to 130 ,g/g (P = 0.001) and fecal lactoferrin from 105.0 ,g/g to 2.7 ,g/g (P = 0.001). Of the 15 patients, 11 (73%) showed an endoscopic response to treatment and 5 of these achieved endoscopic remission (CDEIS < 3). In those 5 patients the fecal calprotectin concentration declined from 1891 ,g/g (range 813,2434) to 27 ,g/g (13,130) and lactoferrin from 92.4 ,g/g (35.5,235.6) to 1.9 ,g/g (0.0,2.1). Conclusions: Compared to pretreatment values, concentrations of fecal calprotectin and lactoferrin after the anti-TNF-, treatment were significantly lower. During anti-TNF-, therapy these fecal neutrophil-derived proteins may thus be useful surrogate markers for mucosal healing. (Inflamm Bowel Dis 2008) [source]

Plasma microRNAs are promising novel biomarkers for early detection of colorectal cancer

Zhaohui Huang
Abstract MicroRNA (miRNA) opens up a new field for molecular diagnosis of cancer. However, the role of circulating miRNAs in plasma/serum in cancer diagnosis is not clear. The aim of this study was to investigate whether plasma miRNAs can be used as biomarkers for the early detection of colorectal carcinoma (CRC). We measured the levels of 12 miRNAs (miR-134, ,146a, ,17-3p, ,181d, ,191, ,221, ,222, ,223, ,25, ,29a, ,320a and ,92a) in plasma samples from patients with advanced colorectal neoplasia (carcinomas and advanced adenomas) and healthy controls using real-time RT-PCR. We found that plasma miR-29a and miR-92a have significant diagnostic value for advanced neoplasia. MiR-29a yielded an AUC (the areas under the ROC curve) of 0.844 and miR-92a yielded an AUC of 0.838 in discriminating CRC from controls. More importantly, these 2 miRNAs also could discriminate advanced adenomas from controls and yielded an AUC of 0.769 for miR-29a and 0.749 for miR-92a. Combined ROC analyses using these 2 miRNAs revealed an elevated AUC of 0.883 with 83.0% sensitivity and 84.7% specificity in discriminating CRC, and AUC of 0.773 with 73.0% sensitivity and 79.7% specificity in discriminating advanced adenomas. Collectively, these data suggest that plasma miR-29a and miR-92a have strong potential as novel noninvasive biomarkers for early detection of CRC. [source]

Quantification of hepatic steatosis with MRI: The effects of accurate fat spectral modeling

Scott B. Reeder MD
Abstract Purpose To develop a chemical-shift,based imaging method for fat quantification that accounts for the complex spectrum of fat, and to compare this method with MR spectroscopy (MRS). Quantitative noninvasive biomarkers of hepatic steatosis are urgently needed for the diagnosis and management of nonalcoholic fatty liver disease (NAFLD). Materials and Methods Hepatic steatosis was measured with "fat-fraction" images in 31 patients using a multiecho chemical-shift,based water-fat separation method at 1.5T. Fat-fraction images were reconstructed using a conventional signal model that considers fat as a single peak at ,210 Hz relative to water ("single peak" reconstruction). Fat-fraction images were also reconstructed from the same source images using two methods that account for the complex spectrum of fat; precalibrated and self-calibrated "multipeak" reconstruction. Single-voxel MRS that was coregistered with imaging was performed for comparison. Results Imaging and MRS demonstrated excellent correlation with single peak reconstruction (r2 = 0.91), precalibrated multipeak reconstruction (r2 = 0.94), and self-calibrated multipeak reconstruction (r2 = 0.91). However, precalibrated multipeak reconstruction demonstrated the best agreement with MRS, with a slope statistically equivalent to 1 (0.96 0.04; P = 0.4), compared to self-calibrated multipeak reconstruction (0.83 0.05, P = 0.001) and single-peak reconstruction (0.67 0.04, P < 0.001). Conclusion Accurate spectral modeling is necessary for accurate quantification of hepatic steatosis with MRI. J. Magn. Reson. Imaging 2009;29:1332,1339. 2009 Wiley-Liss, Inc. [source]

Validation of connective tissue growth factor (CTGF/CCN2) and its gene polymorphisms as noninvasive biomarkers for the assessment of liver fibrosis

E. Kovalenko
Summary., Clinical and experimental studies have demonstrated that connective-tissue growth factor (CTGF) expression is increased in fibrotic human liver and experimental animal models of liver fibrogenesis. CTGF has been linked to transforming growth factor-beta (TGF-,) pathways in fibroproliferative diseases and specific polymorphisms within the CTGF gene may predispose for fibrosis in systemic sclerosis. As CTGF is detectable in various human fluids (serum, plasma and urine), it may provide information about fibrotic remodelling processes and reflect hepatic TGF-, bioactivity. We established a novel ELISA for the measurement of serum CTGF and tested its clinical value in patients with chronic hepatitis C virus (HCV) infection and chronic liver disease (CLD). HCV infected patients (n = 138) had significantly higher serum CTGF levels than healthy controls. CTGF was linked to the histological degree of liver fibrosis. To expand the results to other aetiologies, a separate cohort of CLD patients (n = 129) was evaluated, showing higher serum CTGF than healthy controls and again an association with advanced stages of liver cirrhosis (Child B and C). Although independent of the underlying aetiology, serum CTGF was most powerful in indicating fibrosis/advanced disease states in HCV-related disorders. The genotyping of six polymorphisms (rs6917644, rs9399005, rs6918698, rs9493150, rs2151532 and rs11966728) covering the CTGF locus in 365 patients suffering from chronic hepatitis C revealed that none of these polymorphisms showed a genotypic or allelic association with the severity of hepatic fibrosis. Taken together, serum CTGF is suitable for determination of hepatic fibrosis and most powerful in patients with chronic HCV infection. [source]