Barrett's oesophagus: Epidemiology, cancer risk and implications for management

Although endoscopic surveillance of patients with Barrett's oesophagus has been widely implemented, its effectiveness is debateable. The recently reported low annual oesophageal adenocarcinoma risk in population studies, the failure to identify most Barrett's patients at risk of disease progression, the poor adherence to surveillance and biopsy protocols, and the significant risk of misclassification of dysplasia all tend to undermine the effectiveness of current management, in particular, endoscopic surveillance programmes, to prevent or improve the outcomes of patients with oesophageal adenocarcinoma. The ongoing increase in incidence of Barrett's oesophagus and consequent growth of the surveillance population, together with the associated discomfort and costs of endoscopic surveillance, demand improved techniques for accurately determining individual risk of oesophageal adenocarcinoma. More accurate techniques are needed to run efficient surveillance programmes in the coming decades. In this review, we will discuss the current knowledge on the epidemiology of Barrett's oesophagus, and the challenging epidemiological dilemmas that need to be addressed when a

The minimal incubation period from the onset of Barrett's oesophagus to symptomatic adenocarcinoma

Background:The interval between the onset of Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC) can be termed the incubation period. However, the unrecorded onset of BO precludes its direct observation.Methods:Determining the range of intervals between BO diagnosis and OAC within the longest observational BO follow-up study. Exclusion criteria were presence of high-grade dysplasia (HGD) or OAC at baseline, death within <2 years of BO diagnosis, oesophagectomy without HGD/OAC and loss to follow-up. A total of 133 patients (M/F 73/60) were taken into account.Results:In 1967 person years of follow-up there were 13 cases of HGD/OAC, (0.66% p.a.; 95% CI 0.58-0.74), 96 patients died without HGD/OAC and 24 survived without HGD/OAC. The mean intervals between BO diagnosis and either HGD/OAC, death or end of follow-up were 10.8, 12.6 and 25.5 years, respectively, and the mean ages at endpoint were 72.5, 80.0 and 68.3 years, respectively. The survivors without HGD/OAC had a lower age at BO diagnosis (mean 42.8 vs 61.2 and 67.4 years, P=0.001). Baseline presence of low-grade dysplasia was associated with progression to HGD/OAC (log rank P=0.001).Conclusion:The Rotterdam BO follow-up cohort revealed a long incubation period between onset of BO and development of HGD/OAC, in patients without HGD/OAC at baseline as illustrated by 24 patients diagnosed with BO at a young age and followed for a mean period of 25.5 years. Their tumour-free survival established a minimum incubation period, suggesting a true incubation period of three decades or more

Tomography of entangling two-qubit logic operations in exchange-coupled donor electron spin qubits

Scalable quantum processors require high-fidelity universal quantum logic operations in a manufacturable physical platform. Donors in silicon provide atomic size, excellent quantum coherence and compatibility with standard semiconductor processing, but no entanglement between donor-bound electron spins has been demonstrated to date. Here we present the experimental demonstration and tomography of universal 1- and 2-qubit gates in a system of two weakly exchange-coupled electrons, bound to single phosphorus donors introduced in silicon by ion implantation. We surprisingly observe that the exchange interaction has no effect on the qubit coherence. We quantify the fidelity of the quantum operations using gate set tomography (GST), and we use the universal gate set to create entangled Bell states of the electrons spins, with fidelity ~ 93%, and concurrence 0.91 +/- 0.08. These results form the necessary basis for scaling up donor-based quantum computers

Neurobiological correlates of antisociality across adolescence and young adulthood: a multi-sample, multi-method study

Background Antisociality across adolescence and young adulthood puts individuals at high risk of developing a variety of problems. Prior research has linked antisociality to autonomic nervous system and endocrinological functioning. However, there is large heterogeneity in antisocial behaviors, and these neurobiological measures are rarely studied conjointly, limited to small specific studies with narrow age ranges, and yield mixed findings due to the type of behavior examined. Methods We harmonized data from 1489 participants (9-27 years, 67% male), from six heterogeneous samples. In the resulting dataset, we tested relations between distinct dimensions of antisociality and heart rate, pre-ejection period (PEP), respiratory sinus arrhythmia, respiration rate, skin conductance levels, testosterone, basal cortisol, and the cortisol awakening response (CAR), and test the role of age throughout adolescence and young adulthood. Results Three dimensions of antisociality were uncovered: 'callous-unemotional (CU)/manipulative traits', 'intentional aggression/conduct', and 'reactivity/impulsivity/irritability'. Shorter PEPs and higher testosterone were related to CU/manipulative traits, and a higher CAR is related to both CU/manipulative traits and intentional aggression/conduct. These effects were stable across age. Conclusions Across a heterogeneous sample and consistent across development, the CAR may be a valuable measure to link to CU/manipulative traits and intentional aggression, while sympathetic arousal and testosterone are additionally valuable to understand CU/manipulative traits. Together, these findings deepen our understanding of the fundamental mechanisms underlying different components of antisociality. Finally, we illustrate the potential of using current statistical techniques for combining multiple datasets to draw robust conclusions about biobehavioral associations

Guidelines for the application of surgery and endoprostheses in the palliation of obstructive jaundice in advanced cancer of the pancreas

Objective: This study was set up to identify patient-related factors favoring the application of either surgery or endoprostheses in the palliation of obstructive jaundice in subsets of patients with cancer of the head of the pancreas or periampullary region. Summary Background Data: In the palliation of obstructive jaundice, surgical biliodigestive anastomosis has traditionally been performed. Surgical biliary bypass is associated with high mortality (15% to 30%) and morbidity rates (20% to 60%) but little recurrent obstructive jaundice (0% to 15%). Biliary drainage with endoscopically placed endoprostheses has a lower complication rate, but recurrent obstructive jaundice is seen in up to 20% to 50% of patients. Methods: Patients with advanced cancer of the head of the pancreas or periampullary region treated at the University Hospital Dijkzigt, Rotterdam, The Netherlands, between 1980 and 1990 were reviewed. In 148 patients, data were compared concerning the morbidity and hospital stay after the palliation of obstructive jaundice with endoscopic endoprostheses or surgical biliary bypasses. These patients were stratified for long (> 6 months) and short (< 6 months) survival times. Results: In short-term survivors, the higher late morbidity rates after endoprostheses were offset by higher early morbidity rates and longer hospital stays after the surgical bypass. In long-term survivors, there was no difference in the hospital stay between the two groups, but the late morbidity rate was significantly higher in the endoprosthesis group. Conclusions: These data suggest that endoscopic endoprosthesis is the optimal palliation for patients surviving less than 6 months and surgical biliary bypass for those surviving more than 6 months. This policy necessitates the development of prognostic criteria, which were obtained by Cox proportional- hazards survival analysis. Advanced age, m