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1.
Am J Gastroenterol ; 110(11): 1549-58, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26416188

ABSTRACT

OBJECTIVES: Barrett's esophagus (BE) surveillance with white-light endoscopy and quadrantic biopsies (Seattle protocol) is resource intensive and limited by sampling error. Previous work suggests that autofluorescence imaging (AFI) in combination with a molecular panel might reduce the number of biopsies, but this was not sufficiently sensitive for low-grade dysplasia, now a point for endoscopic intervention. Here we used AFI to direct narrow-field imaging tools for real-time optical assessment of dysplasia and biopsies for a biomarker panel. We compared the new diagnostic algorithm with the current standard. METHODS: A total of 55 patients with BE were recruited at a single tertiary referral center. Patients underwent high-resolution endoscopy followed by AFI. AFI-targeted areas (n=194) were examined in turn by narrow-band imaging with magnification (NBIz) and probe-based confocal laser endomicroscopy (pCLE). Biopsies were taken from AFI-targeted areas and tested using an established molecular panel comprising aneuploidy plus cyclin A and p53 immunohistochemistry. RESULTS: In the per-patient analysis the overall sensitivity and specificity of AFI-targeted pCLE were 100% and 53.6% for high-grade dysplasia/intramucosal cancer and 96.4% and 74.1% for any grade of dysplasia, respectively. NBIz had equal specificity for dysplasia detection (74.1%), but significantly lower sensitivity (57.1%) than pCLE. The time required to perform AFI-targeted pCLE was shorter that that taken by the Seattle protocol (P=0.0004). We found enrichment of molecular abnormalities in areas with optical dysplasia by pCLE (P<0.001), regardless of histologic dysplasia. The addition of the 3-biomarker panel reduced the false positive rate of pCLE by 50%, leading to sensitivity and specificity for any grade of dysplasia of 89.2% and 88.9%, respectively. CONCLUSIONS: The combination of pCLE on AFI-targeted areas and a 3-biomarker panel identifies patients with dysplasia.


Subject(s)
Barrett Esophagus/metabolism , Barrett Esophagus/pathology , Optical Imaging , Precancerous Conditions/chemistry , Precancerous Conditions/pathology , Watchful Waiting/methods , Aged , Algorithms , Aneuploidy , Barrett Esophagus/genetics , Biomarkers/analysis , Biopsy , Cyclin A/analysis , Disease Progression , Esophagoscopy , Esophagus/pathology , False Positive Reactions , Female , Humans , Male , Microscopy, Confocal/methods , Middle Aged , Narrow Band Imaging , Precancerous Conditions/genetics , Sensitivity and Specificity , Tumor Suppressor Protein p53/analysis
2.
Behav Anal Pract ; 8(1): 52-56, 2015 May.
Article in English | MEDLINE | ID: mdl-27703881

ABSTRACT

Problem gambling is a global concern, and behavior analytic attention has increasingly focused on reasons for why problem gambling occurs and conditions under which it is maintained. However, limited knowledge currently exists on the process to which self-generated rules maintain gambling behaviors. Therefore, the current study assessed six recreational gamblers on a roulette game before and after discrimination training to establish a self-rule to wager on red or black. Following discrimination training, all six participants altered their response allocation among red or black and consistently responded according to the newly derived self-rule. Results maintained during 1-week follow-up sessions across all participants. Implications for clinical application of self-awareness and self-generated rule following are discussed. Implications for practice • Demonstration of how stimuli such as color can alter gambling behavior • Procedures to assist clients with changing self-rules about gambling behavior • Using self-generated rule formulation for more contextually appropriate target behaviors • Highlights how self-generated rules can be altered to change clinical target behaviors.

3.
Gut ; 64(1): 49-56, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24721904

ABSTRACT

OBJECTIVE: Endoscopic surveillance for Barrett's oesophagus (BO) is limited by sampling error and the subjectivity of diagnosing dysplasia. We aimed to compare a biomarker panel on minimal biopsies directed by autofluorescence imaging (AFI) with the standard surveillance protocol to derive an objective tool for dysplasia assessment. DESIGN: We performed a cross-sectional prospective study in three tertiary referral centres. Patients with BO underwent high-resolution endoscopy followed by AFI-targeted biopsies. 157 patients completed the biopsy protocol. Aneuploidy/tetraploidy; 9p and 17p loss of heterozygosity; RUNX3, HPP1 and p16 methylation; p53 and cyclin A immunohistochemistry were assessed. Bootstrap resampling was used to select the best diagnostic biomarker panel for high-grade dysplasia (HGD) and early cancer (EC). This panel was validated in an independent cohort of 46 patients. RESULTS: Aneuploidy, p53 immunohistochemistry and cyclin A had the strongest association with dysplasia in the per-biopsy analysis and, as a panel, had an area under the receiver operating characteristic curve of 0.97 (95% CI 0.95 to 0.99) for diagnosing HGD/EC. The diagnostic accuracy for HGD/EC of the three-biomarker panel from AFI+ areas was superior to AFI- areas (p<0.001). Compared with the standard protocol, this panel had equal sensitivity for HGD/EC, with a 4.5-fold reduction in the number of biopsies. In an independent cohort of patients, the panel had a sensitivity and specificity for HGD/EC of 100% and 85%, respectively. CONCLUSIONS: A three-biomarker panel on a small number of AFI-targeted biopsies provides an accurate and objective diagnosis of dysplasia in BO. The clinical implications have to be studied further.


Subject(s)
Barrett Esophagus/pathology , Biomarkers/analysis , Esophagoscopy , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Image-Guided Biopsy/methods , Male , Middle Aged , Optical Imaging , Prospective Studies
4.
Biol Psychiatry ; 69(11): 1109-16, 2011 Jun 01.
Article in English | MEDLINE | ID: mdl-21392734

ABSTRACT

BACKGROUND: Behavioral inflexibility is a feature of schizophrenia, attention-deficit/hyperactivity disorder, and behavior addictions that likely results from heritable deficits in the inhibitory control over behavior. Here, we investigate the genetic basis of individual differences in flexibility, measured using an operant reversal learning task. METHODS: We quantified discrimination acquisition and subsequent reversal learning in a cohort of 51 BXD strains of mice (2-5 mice/strain, n = 176) for which we have matched data on sequence, gene expression in key central nervous system regions, and neuroreceptor levels. RESULTS: Strain variation in trials to criterion on acquisition and reversal was high, with moderate heritability (∼.3). Acquisition and reversal learning phenotypes did not covary at the strain level, suggesting that these traits are effectively under independent genetic control. Reversal performance did covary with dopamine D2 receptor levels in the ventral midbrain, consistent with a similar observed relationship between impulsivity and D2 receptors in humans. Reversal, but not acquisition, is linked to a locus on mouse chromosome 10 with a peak likelihood ratio statistic at 86.2 megabase (p < .05 genome-wide). Variance in messenger RNA levels of select transcripts expressed in neocortex, hippocampus, and striatum correlated with the reversal learning phenotype, including Syn3, Nt5dc3, and Hcfc2. CONCLUSIONS: This work demonstrates the clear trait independence between, and genetic control of, discrimination acquisition and reversal and illustrates how globally coherent data sets for a single panel of highly related strains can be interrogated and integrated to uncover genetic sources and molecular and neuropharmacological candidates of complex behavioral traits relevant to human psychopathology.


Subject(s)
Genome , Reversal Learning/physiology , Animals , Behavior, Animal , Male , Mice , Species Specificity
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