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Purpose of review Gastric outlet obstruction is a syndrome that is caused by several benign and malignant diseases. Endoscopic ultrasonography-guided gastroenterostomy (EUS-GE) is a novel treatment that seems to combine the advantages of the two traditional treatments: enteral stent placement (ES) and surgical gastrojejunostomy (SGJ). This review aims to determine the current position of EUS-GE amidst the two traditional treatment options. Recent findings Different approaches can be adopted to facilitate EUS-GE. Direct gastroenterostomy seems to have the shortest procedure time. All methods possess high technical success rates. Several retrospective analyses have compared EUS-GE to ES and SGJ. EUS-GE seems to have better stent patency compared to ES and a lower adverse event rate compared to SGJ. Recently, randomized trials have been initiated which compare EUS-GE with ES or SGJ. Summary Although the currently published literature unequivocally shows the great promises of EUS-GE, properly powered and controlled studies are warranted to ascertain the definitive position of EUS-GE within the treatment repertoire of GOO. Until reliable data has been collected, EUS-GE can be considered a safe and effective alternative to ES and SGJ.

Background Selective cannulation and stenting of complex, tight, and/or angulated biliary strictures under endoscopic retrograde cholangiopancreaticography (ERCP) can be challenging. Digital single-operator cholangioscopy (SOC) may facilitate guidewire advancement through the stricture with endoscopic visual guidance. We aimed to describe a case series on clinical outcomes of this technique for selective cannulation, when used after failed conventional ERCP attempts. Methods Consecutive patients who underwent therapeutic digital SOC for selective cannulation of biliary strictures after failed conventional ERCP were retrospectively included. Results Ten patients with a malignant (n = 6) or benign (n = 4) biliary stricture were included. Digital SOC-assisted selective guidewire insertion and stent placement across the biliary stricture were technically successful in five (50%) patients. Bilirubin levels improved in all patients with technical success. One (10%) patient developed a post-ERCP pancreatitis. Conclusions Technically successful cannulation of biliary strictures with digital SOC was achieved in half of patients in whom cannulation with conventional ERCP failed, sparing them more invasive interventions. Stricture opacification during the failed ERCP was seen in all technically successful SOCs.

Contains fulltext : 245188.pdf (Publisher’s version ) (Open Access) The upper gastrointestinal tract, consisting of the esophagus, stomach, and duodenum, controls food transport, digestion, nutrient uptake, and hormone production. By single-cell analysis of healthy epithelia of these human organs, we molecularly define their distinct cell types. We identify a quiescent COL17A1(high) KRT15(high) stem/progenitor cell population in the most basal cell layer of the esophagus and detect substantial gene expression differences between identical cell types of the human and mouse stomach. Selective expression of BEST4, CFTR, guanylin, and uroguanylin identifies a rare duodenal cell type, referred to as BCHE cell, which likely mediates high-volume fluid secretion because of continual activation of the CFTR channel by guanylin/uroguanylin-mediated autocrine signaling. Serotonin-producing enterochromaffin cells in the antral stomach significantly differ in gene expression from duodenal enterochromaffin cells. We, furthermore, discover that the histamine-producing enterochromaffin-like cells in the oxyntic stomach express the luteinizing hormone, yet another member of the enteroendocrine hormone family.

Additional file 1. SPIRIT 2013 Checklist for the PACAP-1 trial.

Background and study aims Fully covered self-expanding metal stents (FCSEMS) provide an alternative to bougie dilation (BD) for refractory benign esophageal strictures. Controlled studies comparing temporary placement of FCSES to repeated BD are not available. Patients and methods Patients with refractory anastomotic esophageal strictures, dysphagia scores ≥ 2, and two to five prior BD were randomized to 8 weeks of FCSEMS or to repeated BD. The primary endpoint was the number of BD during the 12 months after baseline treatment. Results Eighteen patients were included (male 67 %, median age 66.5; 9 received metal stents, 9 received BD). Technical success rate of stent placement and stent removal was 100 %. Recurrent dysphagia occurred in 13 patients (72 %) during follow-up. No significant difference was found between the stent and BD groups for mean number of BD during follow-up (5.4 vs. 2.4, P = 0.159), time to recurrent dysphagia (median 36 days vs. 33 days, Kaplan-Meier: P = 0.576) and frequency of reinterventions per month (median 0.3 vs. 0.2, P = 0.283). Improvement in quality of life score was greater in the stent group compared to the BD group at month 12 (median 26 % vs. 4 %, P = 0.011). Conclusions The current data did not provide evidence for a statistically significant difference between the two groups in the number of BD during the 12 months after initial treatment. Metal stenting offers greater improvement in quality of life from baseline at 12 months compared to repeated BD for patients with refractory anastomotic esophageal strictures.

Objectives: Studies on the impact of rapid on-site evaluation (ROSE) during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of lymph nodes are retrospective and have shown conflicting results. We aimed to compare the diagnostic yield of EUS-FNA of lymph nodes with ROSE (ROSE+) and without ROSE (ROSE-). Methods: This was a multicenter, randomized controlled trial. Consecutive patients who were scheduled to undergo EUS-FNA of mediastinal or abdominal lymph nodes were randomized to ROSE+ or ROSE-. In the ROSE+ group, the number of passes was dictated by the on-site cytotechnician. In the ROSE- group, five passes were performed without interference from the cytotechnician. All samples were reviewed by a single-expert cytopathologist, blinded to group allocation. Primary endpoint was diagnostic yield with and without ROSE. Results: After inclusion of 90 patients, interim analysis showed futility of study continuation since diagnostic yield of ROSE+ and ROSE- were comparable. A total of 91 patients were randomized to ROSE+ (N = 45) or ROSE- (N = 46). Diagnostic yield of ROSE+ and ROSE- and diagnostic accuracy were comparable: 93.3% vs. 95.7% (P = 0.68) and 97.6% vs. 93.2% (P = 0.62), respectively. Two major complications (one per group) occurred (p = 0.99). ROSE- patients more often reported self-limiting post-procedural pain (p < 0.001). Median procedure time for ROSE+ (20 min) and ROSE- (23 min) was comparable (P = 0.06). Median time to review slides in the ROSE- group (12:47 min) was longer than with ROSE+ (7:52 min) (P < 0.001). Mean costs of ROSE- and ROSE+ were comparable: €938.29 (±172.70) vs. €945.98 (±223.38) (P = 0.91), respectively. Conclusions: Diagnostic yield and accuracy of EUS-FNA of mediastinal and abdominal lymph nodes with and without ROSE are comparable. Time needed to review slides was shorter and post-procedural pain was less often reported in the ROSE+ group. Based on the primary outcome, the implementation of ROSE during EUS-FNA of mediastinal and abdominal lymph nodes cannot be advised.

Item does not contain fulltext BACKGROUND: The clinical management of patients with non-obstructive dysphagia is notoriously difficult. Esophageal impedance measurement can be used to measure esophageal bolus transit without the use of radiation exposure to patients. However, validation of measurement of bolus transit with impedance monitoring has only been performed in healthy subjects with normal motility and not in patients with dysphagia and esophageal motility disorders. The aim was, therefore, to investigate the relationship between transit of swallowed liquid boluses in healthy controls and in patients with dysphagia. METHODS: Twenty healthy volunteers and 20 patients with dysphagia underwent concurrent impedance measurement and videofluoroscopy. Each subject swallowed five liquid barium boluses. The ability of detecting complete or incomplete bolus transit by means of impedance measurement was assessed, using radiographic bolus transit as the gold standard. KEY RESULTS: Impedance monitoring recognized stasis and transit in 80.5% of the events correctly, with 83.9% of bolus transit being recognized and 77.2% of stasis being recognized correctly. In controls 79.8% of all swallows were scored correctly, whereas in patients 81.3% of all swallows were scored correctly. Depending on the contractility pattern, between 77.0% and 94.3% of the swallows were scored correctly. CONCLUSIONS & INFERENCES: Impedance measurement can be used to assess bolus clearance patterns in healthy subjects, but can also be used to reliably assess bolus transit in patients with dysphagia and motility disorders.

Gastroesophageal reflux is considered to be the most common gastrointestinal cause of non-cardiac chest pain (NCCP). It remains unclear why some reflux episodes in the same patient cause chest pain while others do not. To understand more about the mechanisms by which reflux elicits chest pain, we aimed to identify factors which are important in triggering chest pain. In this multicenter study, 120 patients with NCCP were analyzed using 24-h pH-impedance monitoring. In the patients with a positive association between reflux and chest pain, the characteristics of the reflux episodes which were followed by a chest pain episode were compared with chest pain-free reflux episodes. Using 24-h pH-impedance monitoring, 40% of the NCCP patients were identified as having reflux as a possible cause of their chest pain. Reflux episodes that were associated with chest pain had a higher proximal extent (P=0.007), a higher volume clearance time (P=0.030), a higher 15-minute acid burden (P=0.041), were more often acidic (P=0.011), had a lower nadir pH (P=0.044), and had a longer acid duration time (P=0.027) than reflux episodes which were not followed by chest pain. Patients who experienced typical reflux symptoms were more likely to have reflux as the cause of their chest pain (52 vs. 31.4%, P=0.023). The presence of a larger volume of acid refluxate for a longer period of time appears to be an important determinant of perceiving a reflux episode as chest pain. 24-h pH-impedance monitoring is an important tool in identifying gastroesophageal reflux as a potential cause of symptoms in patients with NCCP

High-resolution esophageal manometry (HRM) is a recent development used in the evaluation of esophageal function. Our aim was to assess the inter-observer agreement for diagnosis of esophageal motility disorders using this technology. Practitioners registered on the HRM Working Group website were invited to review and classify (i) 147 individual water swallows and (ii) 40 diagnostic studies comprising 10 swallows using a drop-down menu that followed the Chicago Classification system. Data were presented using a standardized format with pressure contours without a summary of HRM metrics. The sequence of swallows was fixed for each user but randomized between users to avoid sequence bias. Participants were blinded to other entries. (i) Individual swallows were assessed by 18 practitioners (13 institutions). Consensus agreement (≤ 2/18 dissenters) was present for most cases of normal peristalsis and achalasia but not for cases of peristaltic dysmotility. (ii) Diagnostic studies were assessed by 36 practitioners (28 institutions). Overall inter-observer agreement was 'moderate' (kappa 0.51) being 'substantial' (kappa > 0.7) for achalasia type I/II and no lower than 'fair-moderate' (kappa >0.34) for any diagnosis. Overall agreement was somewhat higher among those that had performed >400 studies (n = 9; kappa 0.55) and 'substantial' among experts involved in development of the Chicago Classification system (n = 4; kappa 0.66). This prospective, randomized, and blinded study reports an acceptable level of inter-observer agreement for HRM diagnoses across the full spectrum of esophageal motility disorders for a large group of clinicians working in a range of medical institutions. Suboptimal agreement for diagnosis of peristaltic motility disorders highlights contribution of objective HRM metrics.

Item does not contain fulltext Background and aims In multiple endocrine neoplasia type 1 (MEN1), endoscopic ultrasound (EUS) is used for identification and follow-up of pancreatic neuroendocrine tumors (PNETs). The role of EUS in surveillance of small ( < 20 mm) PNETs is unclear, mostly because the natural course of these lesions is largely unknown. We aimed to determine annual growth and incidence rate of small PNETs in patients with MEN1 using EUS-based surveillance. Patients and methods Linear array EUS procedures in patients with MEN1 between 2002 and 2015 were identified. Number, size, and location of PNETs were recorded. Annual growth of PNETs < 20 mm identified at the initial EUS ("prevalent" PNETs) and during follow-up ("incident" PNETs) was calculated using mixed model linear regression analysis. Results A total of 54 patients were identified and 38 patients were included. In all, 226 PNETs were identified (median size 5.0 mm, interquartile range 3.7 - 7.5) of which 124 (55 %) were prevalent and 102 (45 %) were incident PNETs. Annual incidence rate was 0.79 PNETs/year (95 % confidence interval [CI] 0.73 to 0.87). Overall growth rate was 0.10 mm/year (95 %CI 0.02 to 0.19; P = 0.01); PNETs < 10 mm (n = 198) did not grow (P = 0.23), whereas PNETs >/= 10 mm (n = 28) grew 0.44 mm/year (95 %CI 0.10 to 0.78; P = 0.01). Prevalent PNETs grew 0.21 mm/year (95 %CI 0.10 - 0.32; P < 0.001), whereas incident PNETs did not grow (P = 0.26). Conclusions The annual growth rate of small, solid PNETs in patients with MEN1 is lower than previously thought. Surveillance intervals could probably be prolonged without compromising safety.

One of the proposed advantages of laparoscopic inguinal hernia repair is complimentary inspection of the contralateral side and possible detection of occult hernias. Incidence of occult contralateral hernias is as high as 50 %. The natural course of such occult defects is unknown and therefore operative rationale is lacking. This study was designed to analyze the incidence of occult contralateral inguinal hernias and its natural course.A total of 1,681 patients were diagnosed preoperatively with unilateral inguinal hernia. None of these patients had complaints of the contralateral side preoperatively. All patients underwent laparoscopic inguinal hernia transabdominal preperitoneal (TAPP) repair. Operative details were analyzed retrospectively. Patients with occult contralateral defects were identified and tracked. Patients with an evident occult hernia received immediate repair. Patients with a smaller beginning or incipient hernia were followed.In 218 (13 %) patients, an occult hernia was found at the contralateral side during preoperative exploration. In 129 (8 %) patients, an occult true hernia was found. In 89 (5 %) patients, an occult incipient hernia was found. An incipient hernia was defined as a beginning hernia. All patients with an incipient hernia were followed. The mean follow-up was 112 (range 16-218) months. Twenty-eight (32 %) patients were lost to follow-up. In the 61 remaining patients, 13 (21 %) occult incipient hernias became symptomatic requiring repair. The mean time between primary repair and development of a symptomatic hernia on the contralateral side was 88 (range 24-210) months.This study shows that the incidence of occult contralateral hernias is 13 % during TAPP repair of unilateral diagnosed inguinal hernias. In 5 % of the cases, the occult hernia consisted of a beginning hernia. Eventually, one of five will become symptomatic and require repair. These outcomes support immediate repair of occult defects, no matter its size.

Contains fulltext : 172104.pdf (Publisher’s version ) (Open Access) INTRODUCTION: Esophageal dysphagia is a commonly reported symptom with various benign and malignant causes. Esophageal dysphagia can impede intake of oral medication, which often poses a major challenge for both patients and physicians. The best way to address this challenge depends of the cause of dysphagia. AREAS COVERED: The pathophysiology of esophageal dysphagia is discussed, diagnostic tools to determine its cause are reviewed and recent developments in the treatment of esophageal dysphagia are discussed. Alternative options to administer medication in dysphagia are discussed and the appropriateness of them reviewed. EXPERT OPINION: Two ways can be followed to allow medication intake in patients with esophageal dysphagia, i.e. altering medication or resolving dysphagia. The latter is generally preferred, since esophageal dysphagia rarely only impedes medication intake. Esophageal resection is possible in more advanced esophageal cancer stages due to advances in neo-adjuvant therapy. Due to recent improvements in intraluminal radiotherapy, it can be expected that this will be the primary treatment in a palliative setting. Temporary self-expandable metal stent placement is a promising new alternative for bougienage in difficult-to-treat benign strictures.

Contains fulltext : 172489.pdf (Publisher’s version ) (Open Access) Increasing evidence suggests that esophagogastric junction (EGJ) distensibility is predictive of long-term clinical success after achalasia treatment. A new commercially available hydraulic dilation balloon is capable of measuring EGJ opening diameters whilst simultaneously dilating the EGJ. Deployed alongside the endoscope under direct visualization, it is used for dilation of the lower esophageal sphincter in patients with achalasia. Impedance measurement electrodes are incorporated in the catheter shaft in the dilation balloon, which allows measuring the diameter of the EGJ and displaying it in real time before, during and after dilation. This obviates the need for fluoroscopy during the dilation procedure. The extent of recoil of the EGJ after dilation potentially provides a measurement that could be incorporated into a clinical rule for predicting therapeutic success after dilation.

Background Non-obstructive dysphagia patients prove to be a difficult category for clinical management. Esophageal high-resolution manometry (HRM) is a novel method, used to analyze dysphagia. However, it is not yet clear how findings on HRM relate to bolus transport through the esophagus. Methods Twenty healthy volunteers and 20 patients with dysphagia underwent HRM and videofluoroscopy in a supine position. Each subject swallowed five liquid and five solid barium boluses. Esophageal contraction parameters and bolus transport were evaluated with HRM and concurrent videofluoroscopy. Key Results Stasis of liquid and solid barium boluses occurred in patients and in healthy volunteers in 64% and 41% and in 84% and 82% of the swallows, respectively. Overall, 70% of the liquid and 72% of the solid bolus swallows were followed by a peristaltic contraction, the difference not being statistically significant. Statistically significant associations were found for transition zone length of liquid and solid boluses, and for DCI and distal contraction amplitudes for liquid stasis. No correlation was found between the degree of stasis and other manometric parameters. Conclusions & Inferences Stasis of both liquid and solid boluses occurs frequently in patients and in controls and can be regarded as physiological. Motility patterns can predict the effectiveness of bolus transit and level of stasis to some degree but the relationship between esophageal motility and transit is complex and far from perfect. Esophageal manometry is therefore currently deemed unfit to be used for the prediction of bolus transit, and should rather be used for the identification of treatable esophageal motility disorders.

Background Esophageal high-resolution manometry (HRM) is a novel method for esophageal function testing that has prompted the development of new parameters for quantitative analysis of esophageal function. Until now, the reproducibility of these parameters has not been investigated. Methods Twenty healthy volunteers underwent HRM on two separate days. Standard HRM parameters were measured. In addition, in conventional (virtual) line tracings, lower esophageal sphincter (LES) resting pressure, relaxation pressure, and relative relaxation pressure were measured. Firstly, for each variable, the mean percentage of covariation (100 × SD/mean: %COV) was derived as a measure of inter- and intra-individual variation. Secondly, Kendall’s coefficients of concordance (W values) were calculated. Thirdly, Bland–Altman plots were used to express concordance graphically. Key Results Statistically significant concordance values were found for upper esophageal sphincter (UES) pressure (W = 0.90, P = 0.02), transition zone length (W = 0.92, P = 0.01), LES length (W = 0.81, P = 0.04), LES pressure (W = 0.75, P = 0.05), LES relaxation pressure (W = 0.75, P = 0.03), relative LES relaxation pressure (W = 0.78, P = 0.05), gastric pressure (W = 0.81, P = 0.04), and contraction amplitude 5 cm above the LES (W = 0.86, P = 0.03). In conventional setting, only LES resting pressure (W = 0.835, P = 0.03) proved significant. In HRM tracings, concordance values for contraction wave parameters, and in conventional line tracings, LES relaxation pressure and relative relaxation pressure did not reach levels of statistical significance. Conclusions & Inferences Esophageal HRM yields reproducible results. Parameters that represent anatomic structures show better reproducibility than contraction wave parameters. The reproducibility of LES resting and relaxation pressure assessed with HRM is better than with conventional manometry and further supports the clinical use of HRM.

Deficits in executive function (EF), i.e. function of the prefrontal cortex, may be central in the etiology of autism. One of the various aspects of EF is error detection and adjusting behavior after an error. In cognitive tests, adults normally slow down their responding on the next trial after making an error, a compensatory mechanism geared toward improving performance on subsequent trials, and a faculty critically associated with activity in the anterior cingulate cortex (ACC). The current study evaluated post-error slowing in people with high functioning autism (HFA) (n = 36), taking symptom severity into account, compared to the performance of a normal control group (n = 32). Symptom severity in the HFA group was defined in terms of level of adaptation: living independently (outpatients; n = 12) and living residentially (inpatients; n = 24). Half the group of inpatients was on medication; the results of their performance were analyzed separately. A computerized version of a memory search task was used with two response probability conditions. The subjects in the control group adjusted their reaction time (RT) substantially after an error, while the group of participants with HFA appeared to be overall slow, with no significant adjustment of RT after an error. This finding remained significant if the medication factor was taken into account, and was independent of the degree of severity of the autistic disorder, as defined by the dichotomy 'inpatient versus outpatient'. Possible causes and implications of the finding are discussed. (c) 2007 Elsevier Ltd. All rights reserved.

A mesophilic sulfate reducer, strain ASRB2T, was isolated with acetate as sole carbon and energy source from granular sludge of a laboratory-scale upflow anaerobic sludge bed reactor fed with acetate and sulfate. The bacterium was oval-shaped, 1.3 x 1.9-2.2 microns, non-motile and Gram-negative. Optimum growth with acetate occurred around 37 degrees C in freshwater medium (doubling time: 1.7-2.2 d). Enzyme studies indicated that acetate was oxidized via the carbon monoxide dehydrogenase pathway. Growth was not supported by other organic acids, such as propionate, butyrate or lactate, alcohols such as ethanol or propanol, and hydrogen or formate. Sulfite and thiosulfate were also used as electron acceptors, but sulfur and nitrate were not reduced. Phylogenetically, strain ASRB2T clustered with the delta subclass of the Proteobacteria. Its closest relatives were Desulfosarcina variabilis, Desulfacinum infernum and Syntrophus buswellii. Strain ASRB2T is described as the type strain of Desulfobacca acetoxidans gen. nov., sp. nov.

The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.

Various treatment modalities are currently being used in patients with gastroesophageal reflux disease (GERD); however, long-term outcome is not clear. The aim is to evaluate long-term results of GERD treatments with regard to reflux symptoms, use of anti-reflux medication and anti-reflux surgery outcome.Patients who had undergone 24-h pH monitoring for reflux symptoms between January 2002 and March 2012 were invited to fill out the Reflux Disease Questionnaire (RDQ) and a general questionnaire. Patients with and without anti-reflux surgery were compared using multiple linear and logistic regression models.In total, 1027 of 2190 included patients (47%) returned the questionnaires. After exclusion due to predefined criteria, 477 patients were analyzed. Median total RDQ score was 18 points (10.2% symptom-free) in the conservative group (n = 304) and 10 points (31.2% symptom-free) in the surgical group (n = 173) after a mean follow up of 5.1 years. Daily proton pomp inhibitor (PPI) use was higher in the conservative group than in the surgical group (80.9% vs. 51.4%, p = 0.000). Linear regression analysis showed an association between RDQ scores and anti-reflux surgery (β = -5.477, p = 0.001) and male gender (β = -4.306, p = 0.006). Logistic regression analyses showed that daily PPI use was lower in patients who underwent anti-reflux surgery (odds ratio [OR] = 0.24, p = 0.000), while it increased with age (OR = 1.03, p = 0.000).There is still a high prevalence of typical reflux symptoms and daily PPI use in GERD patients after5 years of follow up. Male patients and patients who had undergone anti-reflux surgery were more often asymptomatic. Daily PPI use was lower after anti-reflux surgery, while it increased with age.

The total number of immunocytochemically identified vasopressin (AVP) cells was determined morphometrically in the paraventricular (PVN) and dorsolateral part of the supraoptic nucleus (dl-SON) of the human hypothalamus in 30 subjects ranging in age from 15 to 97 years, including 10 Alzheimer's disease (AD) patients. The aim of the present study was to test the hypothesis that the increased activity of AVP neurons reported earlier is accompanied by an absence of cell loss in these nuclei in senescence and AD. The results show that numbers of immunoreactive AVP cells in the PVN and dl-SON do not decline during aging or in AD. During aging, the number of neurons expressing AVP even increased in the PVN of control subjects. The nuclear diameter of the AVP cells in the PVN and dl-SON showed an increase in old AD patients. It is concluded that no cell loss occurs in the AVP cell population in the PVN and dl-SON during aging and in AD, and that AVP expression increases in the PVN during normal aging, but not in AD.

Non-obstructive dysphagia patients prove to be a difficult category for clinical management. Esophageal high-resolution manometry (HRM) is a novel method, used to analyze dysphagia. However, it is not yet clear how findings on HRM relate to bolus transport through the esophagus.Twenty healthy volunteers and 20 patients with dysphagia underwent HRM and videofluoroscopy in a supine position. Each subject swallowed five liquid and five solid barium boluses. Esophageal contraction parameters and bolus transport were evaluated with HRM and concurrent videofluoroscopy.Stasis of liquid and solid barium boluses occurred in patients and in healthy volunteers in 64% and 41% and in 84% and 82% of the swallows, respectively. Overall, 70% of the liquid and 72% of the solid bolus swallows were followed by a peristaltic contraction, the difference not being statistically significant. Statistically significant associations were found for transition zone length of liquid and solid boluses, and for DCI and distal contraction amplitudes for liquid stasis. No correlation was found between the degree of stasis and other manometric parameters.Stasis of both liquid and solid boluses occurs frequently in patients and in controls and can be regarded as physiological. Motility patterns can predict the effectiveness of bolus transit and level of stasis to some degree but the relationship between esophageal motility and transit is complex and far from perfect. Esophageal manometry is therefore currently deemed unfit to be used for the prediction of bolus transit, and should rather be used for the identification of treatable esophageal motility disorders.

Esophageal high-resolution manometry (HRM) is a novel method for esophageal function testing that has prompted the development of new parameters for quantitative analysis of esophageal function. Until now, the reproducibility of these parameters has not been investigated.Twenty healthy volunteers underwent HRM on two separate days. Standard HRM parameters were measured. In addition, in conventional (virtual) line tracings, lower esophageal sphincter (LES) resting pressure, relaxation pressure, and relative relaxation pressure were measured. Firstly, for each variable, the mean percentage of covariation (100×SD/mean: %COV) was derived as a measure of inter- and intra-individual variation. Secondly, Kendall's coefficients of concordance (W values) were calculated. Thirdly, Bland-Altman plots were used to express concordance graphically.Statistically significant concordance values were found for upper esophageal sphincter (UES) pressure (W=0.90, P=0.02), transition zone length (W=0.92, P=0.01), LES length (W=0.81, P=0.04), LES pressure (W=0.75, P=0.05), LES relaxation pressure (W=0.75, P=0.03), relative LES relaxation pressure (W=0.78, P=0.05), gastric pressure (W=0.81, P=0.04), and contraction amplitude 5cm above the LES (W=0.86, P=0.03). In conventional setting, only LES resting pressure (W=0.835, P=0.03) proved significant. In HRM tracings, concordance values for contraction wave parameters, and in conventional line tracings, LES relaxation pressure and relative relaxation pressure did not reach levels of statistical significance.Esophageal HRM yields reproducible results. Parameters that represent anatomic structures show better reproducibility than contraction wave parameters. The reproducibility of LES resting and relaxation pressure assessed with HRM is better than with conventional manometry and further supports the clinical use of HRM.

The nutristat, a substrate concentration-controlled continuous culture, was used to grow pentachlorophenol (PCP)-degrading microorganisms. The PCP concentration control system consisted of on-line measurement of the PCP concentration in the culture vessel with a tangential filter and a flowthrough spectrophotometer. With PCP concentrations between 45 and 77 microM, a stable situation was established in the nutristat, with an average dilution rate of 0.035 +/- 0.003 h-1. Compared with those of fed-batch cultures and chemostat cultures, the growth rates of microorganisms in the PCP nutristat were significantly higher, leading to considerable time savings in the enrichment procedure. In addition, PCP accumulation to severe inhibitory levels in the culture is prevented because the set point determines the (maximum) PCP concentration in the culture. The use of the nutristat as a tool for the growth of bacteria that degrade toxic compounds is discussed.

A survey was made on the feasibility of on-site anaerobic treatment of domestic wastewater from small scale emissions in The Netherlands. Three 1.2 m3 UASB-reactors (Upflow Anaerobic Sludge Blanket) were tested in different rural locations. The survey made clear that the efficiency of the process is highly dependent on the reactor temperature. Below 12 °C purification was predominantly based on settling, while above 12 °C microbial degradation of organic matter increased. Efficiencies for the removal of total COD and BOD of two of the reactors ranged between 33 and 60%, equalising well performing septic tanks. In one of the reactors the average production of biogas, with a methane content of 78%, was 67 liters per day. Complete transformation of volatile fatty acids (VFA) into biogas was achieved during 3 to 4 months a year at temperatures above 15 °C. In this period, during the second year of operation, the average efficiencies for COD and BOD removal were 60 and 72% respectively, while the maximum gas production reached 300 liters per day. In the latter period the mineralisation rate exceeded the input rate of organic matter, resulting in a decrease of settled material in the reactor. The possibility of high efficiencies during summertime in The Netherlands and the positive results of similar experiments in Indonesia and Latin America lead to the conclusion that anaerobic digestion is a promising process for the (pre-)treatment of domestic waste water in (sub)tropical countries.

Earlier research showed that divided attention, an aspect of executive function, is limited in both children and adults with autism spectrum disorders (ASDs). The current study explored divided attention capacity in adults with ASD and without intellectual disability ( n = 36). Divided attention was tested using a computerized variant of a well-known memory recognition test, with two levels of cognitive load. The effect of cognitive load on reaction time performance is considered to be inversely proportional to divided attention capacity. The study failed to provide a relationship between divided attention and ASD, contrary to earlier research. Findings indicated that only the adults with ASD who used medication had a divided attention deficit, and that this group had specific difficulty reaching a binary decision in a memory search task. An additional finding was that the participants with ASD were overall slow. Possible causes and implications of these findings are discussed.

Objective. One of the main causes of persistent cough is gastro-oesophageal reflux. In these patients, excessive oesophageal acid exposure and/or a temporal association between gastro-oesophageal reflux and cough can be demonstrated during 24-h pH monitoring. Impedance pH monitoring may have a higher yield than pH monitoring alone, but this technique is not yet widely available. The aim of this study was to assess the diagnostic yield of ambulatory 24-h oesophageal pH monitoring for the evaluation of chronic unexplained cough. Material and methods. Twenty-four-hour pH monitoring studies were analysed in 55 patients with chronic cough. In 14 of these studies concurrent ambulatory pressure monitoring was done. A cough episode was considered to be related to reflux if the cough occurred within two minutes after the onset of the reflux episode ("reflux-cough sequence''). Temporal relationships between cough and reflux were expressed by using the symptom association probability (SAP). Results. Thirty-seven patients actually coughed during the 24-h study. Eleven patients (20%) had a positive SAP for the reflux-cough sequence. In 5 patients, reflux followed coughing. Pathological oesophageal acid exposure was found in 15 subjects. Interestingly, only a minority (39.2%) of the cough bursts detected manometrically were marked by patients who had undergone both combined 24-h pH and pressure recording. Conclusions. This study shows that, in a routine clinical setting, combined 24-h pH and pressure monitoring is useful in the evaluation of patients with chronic unexplained cough, as positive findings are not infrequently found and have diagnostic and therapeutic consequences.

The rate of transformation of a pesticide as a function of the depth in the soil is needed as an input into computations on the risk of residues leaching to groundwater. The herbicide bentazone was incubated at 15 degrees C in soil materials derived from four layers at depths of up to 2.5 m in a humic sandy soil profile with a fluctuating water table (0.8 to 1.4 m), while simulating the redox conditions existing in the field. Gamma-irradiation experiments indicated that bentazone is mainly transformed by microbial activity in the soil. The rate constant for transformation was highest in the humic sandy top layer; it decreased with depth in the sandy vadose subsoil. However, material from the top of the phreatic aquifer had a higher rate constant than that from the layers just above. The presence of fossil organic material in the fluviatile water-saturated sediment probably stimulated microbial activity and bentazone transformation. The changes in the transformation rate constant with depth showed the same trend as those in some soil factors, viz organic carbon content, water-extractable phosphorus and microbial density as measured by fluorescence counts. However, the (low) concentration of dissolved organic carbon (DOC) in the top of the aquifer did not fit the trend. The rate constant for bentazone transformation in the layers was higher at lower initial contents of the herbicide.

The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.