Direct observation of organic contaminant uptake, storage, and metabolism within plant roots

Two-photon excitation microscopy (TPEM) is used to visualize and track the uptake and movement of anthracene and phenanthrene from a contaminated growth medium into living unmodified roots of maize and wheat over a 56-day period. The degradation of anthracene was also directly observed within the cortex cells of both species. The power of this technique is that neither the plant nor the compound require altering (staining or sectioning) to visualize them, meaning they are in their natural form throughout the experiment. Initially both compounds bound to the epidermis along the zone of elongation, passing through the epidermal cells to reach the cortex within the root hair, and branching zones of the root. The PAHs entered the epidermis radially; however, once within the cortex cells this movement was dominated by slow lateral movement of both compounds toward the shoot. Highly focused "streams" of compound were observed to form over time; zones where phenanthrene concentrated extended up to 1500 microm in length over a 56-day period, for example, passing through several adjoining cells, and were detectable in cell walls and cell vacuoles. Radial movement was not observed to extend beyond the cortex cells to reach the vascular tissues of the plant. The longitudinal movement of both compounds was not observed to extend beyond the root base into the stem or vegetative parts of the plant. The lateral movement of both compounds within the cortex cells was dominated by movement within the cell walls, suggesting apoplastic flow through multiple cell walls, but with a low level of symplastic movement to transport compound into the cellular vacuoles. Degradation of anthracene to the partial breakdown products anthrone, anthraquinone, and hydroxyanthraquinone was observed directly in the zones of root elongation and branching. The technique and observations have important applications to the fields of agrochemistry and phytoremediation.

Epidemiology of gastro-oesophageal reflux disease: a systematic review

A systematic review of the epidemiology of gastro-oesophageal reflux disease (GORD) has been performed, applying strict criteria for quality of studies and the disease definition used. The prevalence and incidence of GORD was estimated from 15 studies which defined GORD as at least weekly heartburn and/or acid regurgitation and met criteria concerning sample size, response rate, and recall period. Data on factors associated with GORD were also evaluated. An approximate prevalence of 10-20% was identified for GORD, defined by at least weekly heartburn and/or acid regurgitation in the Western world while in Asia this was lower, at less than 5%. The incidence in the Western world was approximately 5 per 1000 person years. A number of potential risk factors (for example, an immediate family history and obesity) and comorbidities (for example, respiratory diseases and chest pain) associated with GORD were identified. Data reported in this systematic review can be interpreted with confidence as reflecting the epidemiology of "true" GORD. The disease is more common in the Western world than in Asia, and the low rate of incidence relative to prevalence reflects its chronicity. The small number of studies eligible for inclusion in this review highlights the need for global consensus on a symptom based definition of GORD.

Epidemiology of gastro-oesophageal reflux disease: a systematic review

A systematic review of the epidemiology of gastro-oesophageal reflux disease (GORD) has been performed, applying strict criteria for quality of studies and the disease definition used. The prevalence and incidence of GORD was estimated from 15 studies which defined GORD as at least weekly heartburn and/or acid regurgitation and met criteria concerning sample size, response rate, and recall period. Data on factors associated with GORD were also evaluated. An approximate prevalence of 10-20% was identified for GORD, defined by at least weekly heartburn and/or acid regurgitation in the Western world while in Asia this was lower, at less than 5%. The incidence in the Western world was approximately 5 per 1000 person years. A number of potential risk factors (for example, an immediate family history and obesity) and comorbidities (for example, respiratory diseases and chest pain) associated with GORD were identified. Data reported in this systematic review can be interpreted with confidence as reflecting the epidemiology of "true" GORD. The disease is more common in the Western world than in Asia, and the low rate of incidence relative to prevalence reflects its chronicity. The small number of studies eligible for inclusion in this review highlights the need for global consensus on a symptom based definition of GORD.

Cardiac findings during uncomplicated acute influenza in ambulatory adults

BACKGROUND

Previous studies have reported abnormal cardiac findings in up to 43% of ambulatory adults with influenza. This study was conducted to determine the frequency, magnitude, and duration of myocardial dysfunction in such persons.

METHODS

We enrolled 30 previously healthy young adults without known cardiovascular disease who presented to the clinic <or=72 h after onset of influenza symptoms and had a positive influenza antigen test. Most patients received antiviral therapy, and all underwent serial electrocardiography and had blood specimens collected on days 1, 4, 11, and 28 after presentation for measurement of total creatine kinase (CK) level, CK isoenzyme MB (CK-MB) level, troponin I level, and selected cytokine levels. Echocardiography was performed on days 4, 11, and 28.

RESULTS

None of the patients had an elevated CK-MB index or troponin I level. Abnormal electrocardiogram findings were noted in 53%, 33%, 27%, and 23% of patients on days 1, 4, 11, and 28, respectively, but none of the findings were considered to be clinically significant. No patient had significant changes in the ejection fraction or abnormal wall motions.

CONCLUSIONS

Most ambulatory young adults with acute influenza have clinically insignificant abnormal electrocardiogram findings early during the illness. These abnormalities resolve promptly and are not associated with changes in cardiac markers or echocardiogram findings.

Real-time visualization and quantification of PAH photodegradation on and within plant leaves

Vegetation plays a key role in the environmental cycling and fate of many organic chemicals. A compound's location on or within leaves will affect its persistence and significance; retention in surface compartments (i.e., the epicuticular wax and cuticle) renders the compound more susceptible to photodegradation and volatilization, while penetration into the epidermal cell walls or cytoplasm will enhance susceptibility to metabolism. Here, for the first time, methodologies which combine plant and PAH autofluorescence with two-photon excitation microscopy (TPEM) are used to visualize and quantify compound photodegradation on and within living plant leaves. Anthracene,fluoranthene, and phenanthrene were introduced to living leaves of Zea mays and monitored in real time, in control treatments, and when subject to UV-A radiation. Compound photodegradation was observed directly; different degradation rates occurred for different compounds (anthracene > fluoranthene > phenanthrene) and in different locations (at the leaf surface > within the epidermal cells). Results suggest that photodegradation on vegetation may be a more important loss mechanism for PAHs than previously thought. Compound fate in vegetation is potentially highly complex, influenced by diffusion into and location within leaf structures, the rates of supply/loss with the atmosphere, exposure to sunlight, and other environmental conditions. The techniques described here provide a real-time tool to advance insight into these issues.

Gastro-oesophageal reflux disease--current concepts in management

BACKGROUND

Gastro-oesophageal reflux disease (GORD) is defined as recurring symptoms or mucosal damage resulting from exposure of the distal oesophagus to reflux of gastric contents. In the past, GORD has been managed with a 'step up' approach beginning with antacids and progressing to H2 antagonists or proton pump inhibitors (PPI) as required.

OBJECTIVE

This article presents a systematic approach to the management of GORD.

DISCUSSION

Diagnosis of GORD is made on the basis of symptoms and the decision to treat is based on the symptom pattern. Endoscopy is reserved for cases where there are alarm symptoms, diagnostic uncertainty, poor response to treatment or clinical suspicion of a complication such as Barrett's oesophagus or stricture. A 'step down' approach to treatment involves treating with a PPI for 4-8 weeks. Aggressive therapy is then reduced to maintenance doses, intermittent therapy or in some cases, withdrawn. However, relapse occurs in about 70% of all patients within 6 months. A step down approach ensures more rapid resolution of symptoms, improved quality of life, reduced risk of complications, and overall lower cost.

Natural history of gastro-oesophageal reflux disease diagnosed in general practice

BACKGROUND

Cross-sectional studies indicate that gastro-oesophageal reflux disease symptoms have a prevalence of 10-20% in Western countries and are associated with obesity, smoking, oesophagitis, chest pain and respiratory disease.

AIM

To determine the natural history of gastro-oesophageal reflux disease presenting in primary care in the UK.

METHODS

Patients with a first diagnosis of gastro-oesophageal reflux disease during 1996 were identified in the UK General Practice Research Database and compared with age- and sex-matched controls. We investigated the incidence of gastro-oesophageal reflux disease, potential risk factors and comorbidities, and relative risk for subsequent oesophageal complications and mortality.

RESULTS

The incidence of a gastro-oesophageal reflux disease diagnosis was 4.5 per 1000 person-years (95% confidence interval: 4.4-4.7). Prior use of non-steroidal anti-inflammatory drugs, smoking, excess body weight and gastrointestinal and cardiac conditions were associated with an increased risk of gastro-oesophageal reflux disease diagnosis. Subjects with gastro-oesophageal reflux disease had an increased risk of respiratory problems, chest pain and angina in the year after diagnosis, and had a relative risk of 11.5 (95% confidence interval: 5.9-22.3) of being diagnosed with an oesophageal complication. There was an increase in mortality in the gastro-oesophageal reflux disease cohort only in the year following the diagnosis.

CONCLUSIONS

Gastro-oesophageal reflux disease is a disease associated with a range of potentially serious oesophageal complications and extra-oesophageal diseases.

Review article: towards the optimization of symptom evaluation in reflux disease

A recent workshop has taken stock of the processes used for the evaluation of reflux disease symptoms. Such evaluations are vital both for routine clinical practice and for the critical assessment and comparison of therapeutic options. The workshop endorsed the importance of the assessment of symptom patterns for the diagnosis of reflux disease. Patient self-report symptom questionnaires were considered to be potentially valuable instruments, but have been researched relatively little in reflux disease. On the basis of a survey of the literature and data from generic methodological research, the workshop concluded that virtually all trials of the therapy of reflux disease have used too few response options for a sensitive definition of symptom status, and recommended that six to seven response options be used. Modified Likert scales with defined individual response options and structured patient self-report, rather than physician assessment, were considered to be the best approaches. These views on symptom status assessment are not reflected fully in the current practice of reflux disease clinical trials. Furthermore, the terminology used to describe symptom status is frequently ambiguous or tautological. Quality of life measures were acknowledged as valid and useful secondary measures of therapeutic benefit. By contrast, evaluation of the state of the art of assessment of patient satisfaction with therapy led to the conclusion that the methodology for this particular assessment was still in its infancy. The outputs of the workshop revealed many aspects of the assessment of reflux disease that would benefit from further research and development. A report on the detailed outputs of the workshop has been published recently.

Clinical strategies -- interactive case discussions

Interactive case discussions held during the symposium illustrate the practical challenges and dilemmas faced in the management of Barrett's oesophagus. Opinions of the faculty and audience varied widely on how proton pump inhibitor therapy should be used, especially in patients with short-segment Barrett's oesophagus. The therapeutic goal that received most support was to achieve sufficient acid control to keep the patient symptom free and heal any oesophagitis. At the same time, the patient should be reassured of the low risk associated with the endoscopic findings. When long-segment Barrett's oesophagus is detected, it should be assessed in detail, with targeted biopsy of any irregular-surfaced metaplastic mucosa and four quadrant biopsies every 2 cm, to diagnose intestinal metaplasia and to screen for dysplasia or cancer. Repeat endoscopy and biopsy may be appropriate to achieve a sensitive initial assessment because of potential sampling error. Proton pump inhibitor therapy, often twice daily, was considered a requirement for most cases of long-segment Barrett's oesophagus. There was disagreement over the role of surveillance, although proponents viewed it as worthwhile even in patients at low risk for the development of adenocarcinoma, mainly for medico-legal reasons. Endoscopic mucosal resection was seen to be appropriate in carefully selected patients with high-grade dysplasia, depending on factors such as age and comorbidity, the extent of high-grade dysplasia, findings on endoscopic ultrasound and the length of Barrett's oesophagus.

Paradoxical impact of body positioning on gastroesophageal reflux and gastric emptying in the premature neonate

OBJECTIVES

To combine manometry and impedance to characterize the mechanisms of gastroesophageal reflux (GER) and to explore their relation to the rate of gastric emptying (GE) and body position.

STUDY DESIGN

Ten healthy preterm infants (35 to 37 weeks' postmenstrual age) were studied with the use of a micromanometric/impedance assembly. Episodes of GER were identified by impedance, and the mechanism(s) of GER triggering and GER clearance were characterized. GE was determined with a C13Na-octanoate breath test.

RESULTS

Gastroesophageal reflux episodes (n=89) were recorded, consisting of 74% liquid, 14% gas, and 12% mixed. Transient lower esophageal sphincter relaxation (TLESR) was the predominant mechanism of reflux, triggering 83% of GER. Of 92 TLESRs recorded, 27% were not associated with reflux. Infants studied in the right lateral position had significantly (P <.01) more GER, a higher proportion of liquid GER (P <.05), and faster GE (P <.005) when compared with infants studied in the left lateral position.

CONCLUSIONS

In healthy preterm infants, GER is predominantly liquid in nature. Right-side positioning is associated with increased triggering of TLESR and GER despite accelerating GE.

A novel analytical approach for visualizing and tracking organic chemicals in plants

Vegetation plays a key role in the environmental fate of many organic chemicals, from pesticides applied to plants, to the air-vegetation exchange and global cycling of atmospheric organic contaminants. Our ability to locate such compounds in plants has traditionally relied on inferences being made from destructive chemical extraction techniques or methods with potential artifacts. Here, for the first time, two-photon excitation microscopy (TPEM) is coupled with plant autofluorescence to visualize and track trace levels of an organic contaminant in living plant tissue, without any form of sample modification or manipulation. Anthracene-a polynuclear aromatic hydrocarbon (PAH)-was selected for study in living maize (Zea mays) leaves. Anthracene was tracked over 96 h, where amounts as low as approximately 0.1-10 pg were visible, as it moved through the epicuticular wax and plant cuticle, and was observed reaching the cytoplasm of the epidermal cells. By this stage, anthracene was identifiable in five separate locations within the leaf: (1) as a thin (approximately 5 microm) diffuse layer, in the upper surface of the epicuticular wax; (2) as thick (approximately 28 microm) diffuse bands extending from the epicuticular wax through the cuticle, to the cell walls of the epidermal cells; (3) on the external surface of epidermal cell walls; (4) on the internal surface of epidermal cell walls; and (5) within the cytoplasm of the epidermal cells. This technique provides a powerful nonintrusive tool for visualizing and tracking the movement, storage locations, and degradation of organic chemicals within vegetation using only plant and compound autofluorescence. Many other applications are envisaged for TPEM, in visualizing organic chemicals within different matrixes.

Phase II study of docetaxel in combination with epirubicin and protracted venous infusion 5-fluorouracil (ETF) in patients with recurrent or metastatic breast cancer. A Yorkshire breast cancer research group study

This study was originally designed as a phase I/II study, with a dose escalation of docetaxel in combination with epirubicin 50 mg m⁻² and 5-fluorouracil (5-FU) 200 mg m⁻² day⁻¹. However, as dose escalation was not possible, the study is reported as a phase II study of the combination to assess response and toxicity. A total of 51 patients with locally advanced or metastatic breast cancer were treated on this phase II study, with doses of docetaxel 50 mg m⁻², epirubicin 50 mg m⁻² and infusional 5-FU 200 mg m⁻² day⁻¹ for 21 days. The main toxicity of this combination was neutropenia with 89% of patients having grade 3 and 4 neutropenia, and 39% of patients experiencing febrile neutropenia. Nonhaematological toxicity was mild. The overall response rate in the assessable patients was 64%, with median progression-free survival of 38 weeks, and median survival of 70 weeks. The ETF regimen was found to be toxic, and it was not possible to escalate the dose of docetaxel above the first dose level. This regimen has therefore not been taken any further, but as a development of this a new study is ongoing, combining 3-weekly epirubicin, weekly docetaxel and capecitabine, days 1–14.

A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop

BACKGROUND & AIMS

The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues.

METHODS

A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion.

RESULTS

There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia.

CONCLUSIONS

Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines.

Gastro-oesophageal reflux monitoring: review and consensus report on detection and definitions of acid, non-acid, and gas reflux

To date, most concepts on the frequency of gastro-oesophageal reflux episodes and the efficiency of the antireflux barrier have been based on inferences derived from measurement of oesophageal pH. The development of intraluminal impedance monitoring has highlighted the fact that pH monitoring does not detect all gastro-oesophageal reflux events when little or no acid is present in the refluxate, even if special pH tracing analysis criteria are used. In November 2002, a workshop took place at which 11 specialists in the field of gastro-oesophageal reflux disease discussed and criticised all currently available techniques for measurement of reflux. Here, a summary of their conclusions and recommendations of how to achieve the best results from the various techniques now available for reflux measurement is presented.

Symptom evaluation in reflux disease: workshop background, processes, terminology, recommendations, and discussion outputs

There has been no published indepth systematic evaluation of the best approaches to symptom evaluation in gastro-oesophageal reflux disease (GORD). A two day international multidisciplinary workshop was therefore held in Marrakech, Morocco, in September 2002 to address these issues. The aim of the workshop was to critically review the data regarding the reliability, processes, and priorities for symptom evaluation in GORD patients. The workshop was designed to give outputs that could be readily reported and to arrive at specific recommendations on best practice in symptom evaluation in reflux disease.

Impact of endoscopic suturing of the gastroesophageal junction on lower esophageal sphincter function and gastroesophageal reflux in patients with reflux disease

OBJECTIVES

Plication of the gastroesophageal junction by endoscopic suturing has been reported to improve symptoms and reduce acid exposure in patients with gastroesophageal reflux disease (GERD). The mechanisms underlying these effects are not well defined. The aims of our study were to determine the impact of endoscopic suturing of the gastroesophageal junction on lower esophageal sphincter (LES) function in patients with GERD.

METHODS

In 15 patients (7 males) with GERD (heartburn, % time esophageal pH < 4 greater than 4%, +/- history of erosive esophagitis within 6 months), two plications were performed circumferentially 1 cm below the gastroesophageal junction. Endoscopy and combined postprandial esophageal manometry and pH monitoring were performed before and 6 months after treatment; 24-h ambulatory pH monitoring and symptom assessment were also performed before, and at 6 and 12 months after treatment.

RESULTS

Six months after treatment, the rate of transient LES relaxations (tLESRs) was decreased by 37% (p < 0.05) and basal LES pressure had increased from 4.3 +/- 2.2 mmHg to 6.2 +/- 2.1 mmHg (p < 0.05). The rate of postprandial reflux events and acid exposure time were not altered. Endoscopic suturing significantly reduced 24-h esophageal acid exposure from 9.6% (9.0-12.1) to 7.4% (3.9-10.1) at 6 months, due predominantly to a reduction in upright acid exposure. The reduction in total 24-h acid exposure was sustained to 12 months. At repeat endoscopy, only one plication was evident in 6 patients (40%) at 6 months. Seven patients (47%) remained off medications at 6 and 12 months follow-up.

CONCLUSIONS

In patients with GERD, endoscopic suturing of the gastroesophageal junction results in a reduction in the rate of tLESRs, and an increase in basal LES pressure. These changes in LES function result in only a modest reduction in gastroesophageal reflux.

Cure of Helicobacter pylori infection in patients with reflux oesophagitis treated with long term omeprazole reverses gastritis without exacerbation of reflux disease: results of a randomised controlled trial

BACKGROUND

Helicobacter pylori gastritis may progress to glandular atrophy and intestinal metaplasia, conditions that predispose to gastric cancer. Profound suppression of gastric acid is associated with increased severity of H pylori gastritis. This prospective randomised study aimed to investigate whether H pylori eradication can influence gastritis and its sequelae during long term omeprazole therapy for gastro-oesophageal reflux disease (GORD).

METHODS

A total of 231 H pylori positive GORD patients who had been treated for > or =12 months with omeprazole maintenance therapy (OM) were randomised to either continuation of OM (OM only; n = 120) or OM plus a one week course of omeprazole, amoxycillin, and clarithromycin (OM triple; n = 111). Endoscopy with standardised biopsy sampling as well as symptom evaluation were performed at baseline and after one and two years. Gastritis was assessed according to the Sydney classification system for activity, inflammation, atrophy, intestinal metaplasia, and H pylori density.

RESULTS

Corpus gastritis activity at entry was moderate or severe in 50% and 55% of the OM only and OM triple groups, respectively. In the OM triple group, H pylori was eradicated in 90 (88%) patients, and activity and inflammation decreased substantially in both the antrum and corpus (p<0.001, baseline v two years). Atrophic gastritis also improved in the corpus (p<0.001) but not in the antrum. In the 83 OM only patients with continuing infection, there was no change in antral and corpus gastritis activity or atrophy, but inflammation increased (p<0.01). H pylori eradication did not alter the dose of omeprazole required, or reflux symptoms.

CONCLUSIONS

Most H pylori positive GORD patients have a corpus predominant pangastritis during omeprazole maintenance therapy. Eradication of H pylori eliminates gastric mucosal inflammation and induces regression of corpus glandular atrophy. H pylori eradication did not worsen reflux disease or lead to a need for increased omeprazole maintenance dose. We therefore recommend eradication of H pylori in GORD patients receiving long term acid suppression.

Radial distribution of dilated intercellular spaces of the esophageal squamous epithelium in patients with reflux disease exhibiting discrete endoscopic lesions

INTRODUCTION

Dilatation of intercellular spaces of the esophageal squamous epithelium has been suggested as a marker of early acid reflux-induced damage. This change is a potentially useful addition to histomorphological changes that represent so called minimal endoscopic lesions. We have assessed dilatation of intercellular spaces with regard to: (1) interobserver variability, and (2) whether the incidence of this varies between 'red streaks' and the adjacent normal looking squamous epithelium.

METHODS

Esophageal biopsies from 44 patients with chronic gastro-esophageal reflux (GERD) were evaluated. At endoscopy, these patients had one or more red streaks on the tops of the mucosal folds in the distal esophagus. Biopsies were taken from the red streaks and from the normal-appearing mucosa 1 cm lateral to the red streaks. Biopsies were assessed in a blinded fashion by two independent pathologists (MV & RF). Criteria for assessing intercellular space dilatation were evaluated and agreed on prior to the study.

RESULTS

Good interobserver agreement was recorded (kappa = 0.82 at the streaks and 0.77 for the control tissues) for absence/presence of intercellular space dilatation. Red streak and control biopsies differed significantly (p = 0.0001), with respect to presence of dilated intercellular spaces, with 90.5 % of the former demonstrating this as present compared to 56.1% in the controls.

CONCLUSION

This study supports the concept that esophageal mucosal minimal changes due to reflux is localised and that dilatation of intercellular spaces is an early sign of reflux-induced epithelial damage. The low interobserver variability in the assessment of intercellular space dilatation suggests that this may be a useful variable for assessment of early signs of acid-reflux induced damage to the squamous epithelium of the esophagus by use of light microscopy.

Cytogenetic alterations in ovarian clear cell carcinoma detected by comparative genomic hybridisation

Ovarian clear cell carcinoma (OCCC) accounts for a small but significant proportion of all ovarian cancers and is a distinct clinical and pathological entity. It tends to be associated with poorer response rates to chemotherapy and with a worse prognosis. Little is known about possible underlying genetic changes. DNA extracted from paraffin-embedded samples of 18 pure OCCC cases was analysed for genetic imbalances using comparative genomic hybridisation (CGH). All of the 18 cases showed genomic alterations. The mean number of alterations detected by CGH was 6 (range 1-15) indicating a moderate level of genetic instability. Chromosome deletions were more common than amplifications. The most prominent change involved chromosome 9 deletions in 10 cases (55%). This correlates with changes seen in other epithelial ovarian cancers. This deletion was confirmed using microsatellite markers to assess loss of heterozygosity (LOH) at four separate loci on chromosome 9. The most distinct region of loss detected was around the IFNA marker at 9p21 with 41% (11 out of 27 cases) LOH. Other frequent deletions involved 1p (five out of 18; 28%); 11q (four out of 18; 22%) and 16 (five out of 18; 28%). Amplification was most common at chromosome 3 (six out of 18; 33%); 13q (four out of 18; 22%) and 15 (three out of 18; 17%). No high-level amplifications were identified. These features may serve as useful prognostic indicators in the management of OCCC.

Delivery of radiofrequency energy to the lower oesophageal sphincter and gastric cardia inhibits transient lower oesophageal sphincter relaxations and gastro-oesophageal reflux in patients with reflux disease

BACKGROUND AND AIMS

Radiofrequency energy (RFe) treatment to the lower oesophageal sphincter (LOS) and gastric cardia is a new luminally delivered therapy proposed as an alternative treatment for gastro-oesophageal reflux disease (GORD). However, it is unclear how RFe achieves its antireflux effect. This study investigated the effects of RFe on mechanisms of spontaneous reflux in patients with GORD.

METHODS

Twenty patients with GORD underwent endoscopy, symptom evaluation, and combined postprandial oesophageal manometry and pH monitoring before and six months after RFe, and 24 hour ambulatory pH monitoring before and at six and 12 months after treatment.

RESULTS

RFe reduced the rate of postprandial transient LOS relaxations from 6.8 (5.7-8.1) (median (interquartile range) per hour to 5.2 (4.2-5.8) per hour (p<0.01), and increased mean basal LOS pressure from 5.2 (SEM 0.3) mm Hg to 8.0 (SEM 0.4) mm Hg (p<0.01). The number of reflux events was reduced from 10 (2-15.3)/3 hours to 5 (3.5-8.5)/3 hours (p<0.05) and there was an associated significant reduction in acid exposure time from 5.4% (0.4-14.7) to 3.9% (0.4-6.6) (p<0.05). RFe significantly reduced ambulatory oesophageal acid exposure from 10.6% (7.8-13.0) to 6.8% (3.1-9.1) (p<0.01) at six months and 6.3% (4.7-10.9) (p<0.05) at 12 months. All patients required acid suppressant medication for symptom control before RFe. Six months after treatment, 15 patients (75%) were in symptomatic remission and 13 (65%) at 12 months.

CONCLUSIONS

RFe has significant effects on LOS function that are associated with improvement in the antireflux barrier. Uncontrolled clinical data also suggest a beneficial effect in the control of reflux symptoms in these patients.

Overview: initial and long-term management of gastro-oesophageal reflux disease

Initial management of gastro-oesophageal reflux disease aims to confirm a symptom-based diagnosis, to relieve symptoms, to reassure the patient as to the treatable nature of reflux disease, and to initiate risk management and healing of oesophagitis. The aims of long-term management include adequate control of symptoms, prevention of complications, and improvement of quality of life. Management options in terms of use of proton pump inhibitors are either daily therapy (maintenance), intermittent courses of therapy (for example, 4 weeks, then cease and observe), or on-demand therapy. This overview discusses the advantages and disadvantages of these different strategies for the management of reflux disease.

Review article: pharmacology of esomeprazole and comparisons with omeprazole

Plasma concentration measurements have confirmed that the advantageous hepatic metabolism of esomeprazole results in a greater delivery of acid suppressant to the systemic circulation, compared with an equal dose of omeprazole. Also, this superior delivery has been shown to cause a more consistent and greater suppression of pentagastrin-stimulated gastric acid secretion by esomeprazole, 20 mg, compared with omeprazole, 20 mg. The superior acid-suppressant properties of esomeprazole have been revealed by extensive 24-h intragastric pH-monitoring studies. Compared with omeprazole, 20 mg, esomeprazole, 20 mg and 40 mg, has been shown to give superior outcomes on three key measures of antisecretory effect: (1) consistency amongst individuals; (2) duration over the 24-h cycle; (3) overall impact on pH. As there is a substantial increment of acid control from esomeprazole, 20 mg, to esomeprazole, 40 mg, this latter dose is the most appropriate to investigate for modern initial therapy of reflux disease, with the aim of achieving the highest possible response rates in the shortest possible time.

Review article: initial therapy of reflux disease with esomeprazole

Large clinical trials in patients with reflux oesophagitis have shown esomeprazole, 40 mg once daily, to be convincingly superior in the healing of oesophagitis when compared with both omeprazole, 20 mg once daily, and lansoprazole, 30 mg once daily. The greatest advantage for esomeprazole is with healing of the more severe grades of oesophagitis. Esomeprazole, 40 mg once daily, has also been shown to be significantly superior in the treatment of heartburn. Studies in endoscopy-negative patients, or in both oesophagitis and endoscopy-negative patients, have demonstrated good efficacy for esomeprazole, with high levels of symptom control achieved in the first 7 days of therapy.

Radiofrequency energy delivery to the gastric cardia inhibits triggering of transient lower esophageal sphincter relaxation and gastroesophageal reflux in dogs

BACKGROUND

Delivery of radiofrequency energy to the lower esophageal sphincter and gastric cardia is a new endoluminal technique proposed for the treatment of reflux disease. The mechanisms by which it achieves its effects are unclear. The study assessed the effect of radiofrequency energy delivery to the gastric cardia on the triggering of transient lower esophageal sphincter relaxations and gastroesophageal reflux in dogs.

METHODS

In 13 dogs, esophageal motility and pH were measured for 1 hour after a standard liquid meal and air infusion, as well as before and 3 months after radiofrequency energy treatment. At 7 months, histologic evaluation of the gastroesophageal junction was performed.

RESULTS

Radiofrequency energy delivery reduced the frequency of transient lower esophageal sphincter relaxations from 4.0 (3.0-6.75) (median [interquartile range]) per hour to 3.0 (2.0-3.0) per hour (p < 0.05). This was accompanied by a significant reduction in acid reflux episodes and esophageal acid exposure. Basal lower esophageal sphincter pressure and lower esophageal sphincter relaxation during swallowing were unchanged. There was a 63% increase in wall thickness at the gastric cardia compared with that in 2 control dogs, but no gross or histopathologic abnormalities of the esophageal or gastric mucosa.

CONCLUSION

Radiofrequency energy delivery to the gastric cardia in dogs inhibits the triggering of transient lower esophageal sphincter relaxations and thereby reduces gastroesophageal reflux.