MDCT of retractor-related hepatic injury following laparoscopic surgery: appearances, incidence, and follow-up.

AIMS: To investigate the postoperative computed tomography (CT) features resulting from the use of Nathanson retractors during laparoscopic upper gastro-intestinal surgery. MATERIALS AND METHODS: A 3-year retrospective study of 176 patients who had undergone laparoscopic upper gastro-intestinal surgery for bariatric or malignant disease was performed. Postoperative CT images [divided into early (≤ 30 days) and late (>30 days)] were assessed by a consultant radiologist and liver abnormalities recorded. RESULTS: The features of a retractor injury were a hypodense lesion, abutting the liver edge, usually triangular or linear in shape. Late postoperative features included focal subcapsular retraction and associated liver atrophy. Sixty-eight percent (52/77) of patients undergoing surgery for malignancy underwent postoperative CT, compared with 11% (11/99) of those undergoing bariatric surgery. Patients with malignancy were more likely to have retraction-related liver abnormalities (14/52, 27%) at postoperative CT than those in the bariatric group (2/11, 18%). CONCLUSION: Retractor-related liver injuries at MDCT are common following laparoscopic upper gastro-intestinal surgery. Recognition of the characteristic triad of features, a hypodense lesion abutting the liver edge with a triangular or linear shape, should allow confident diagnosis. CT follow-up reveals that over time these lesions may disappear, remain unchanged, or result in a focal subcapsular scar with associated atrophy.

Practical applications of digital tomosynthesis of the chest.

Digital tomosynthesis is a radiographic technique that generates a number of coronal raw images of a patient from a single pass of the x-ray tube. Tomosynthesis provides some of the tomographic benefits of computed tomography (CT), but at a much lower dose of radiation and cost when compared to CT. This review illustrates the range of practical applications of digital tomosynthesis of the chest.

Pancreatic splenosis demonstrated by contrast-enhanced sonography.

Pancreatic splenosis is a very rare condition whose features on contrast-enhanced ultrasound (CEUS) have not, to our knowledge, been previously reported. We present the imaging findings in a case of pancreatic splenosis, in which a confident diagnosis was achieved with the use of CEUS and confirmed by a labeled heat denatured red cell scan. Accumulation of ultrasound contrast microbubbles in splenic tissue can be readily visualized on late-phase CEUS and this technique has already been used to confirm the nature of intrapancreatic accessory spleens. This case shows that it can also confirm the diagnosis of splenosis.

Sand aspiration: a case report and review of the radiological features and management.

We report a case of severe sand aspiration in association with near-drowning, which led to respiratory failure secondary to the acute respiratory distress syndrome, necessitating mechanical ventilation, repeated therapeutic bronchoscopic lavage, and a stay in the intensive care unit that exceeded one month.

A molecular mechanism of integrin crosstalk: alphavbeta3 suppression of calcium/calmodulin-dependent protein kinase II regulates alpha5beta1 function.

Many cells express more than one integrin receptor for extracellular matrix, and in vivo these receptors may be simultaneously engaged. Ligation of one integrin may influence the behavior of others on the cell, a phenomenon we have called integrin crosstalk. Ligation of the integrin alphavbeta3 inhibits both phagocytosis and migration mediated by alpha5beta1 on the same cell, and the beta3 cytoplasmic tail is necessary and sufficient for this regulation of alpha5beta1. Ligation of alpha5beta1 activates the calcium- and calmodulin-dependent protein kinase II (CamKII). This activation is required for alpha5beta1-mediated phagocytosis and migration. Simultaneous ligation of alphavbeta3 or expression of a chimeric molecule with a free beta3 cytoplasmic tail prevents alpha5beta1-mediated activation of CamKII. Expression of a constitutively active CamKII restores alpha5beta1 functions blocked by alphavbeta3-initiated integrin crosstalk. Thus, alphavbeta3 inhibition of alpha5beta1 activation of CamKII is required for its role in integrin crosstalk. Structure-function analysis of the beta3 cytoplasmic tail demonstrates a requirement for Ser752 in beta3-mediated suppression of CamKII activation, while crosstalk is independent of Tyr747 and Tyr759, implicating Ser752, but not beta3 tyrosine phosphorylation in initiation of the alphavbeta3 signal for integrin crosstalk.

The effect of consultant outcome publication on surgeon behaviour: a systematic review and narrative synthesis.

Introduction Surgeon-specific outcome data, or consultant outcome publication, refers to public access to named surgeon procedural outcomes. Consultant outcome publication originates from cardiothoracic surgery, having been introduced to US and UK surgery in 1991 and 2005, respectively. It has been associated with an improvement in patient outcomes. However, there is concern that it may also have led to changes in surgeon behaviour. This review assesses the literature for evidence of risk-averse behaviour, upgrading of patient risk factors and cessation of low-volume or poorly performing surgeons. Materials and methods A systematic literature review of Embase and Medline databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Original studies including data on consultant outcome publication and its potential effect on surgeon behaviour were included. Results Twenty-five studies were identified from the literature search. Studies suggesting the presence of risk-averse behaviour and upgrading of risk factors tended to be survey based, with studies contrary to these findings using recognised regional and national databases. Discussion and conclusion Our review includes instances of consultant outcome publication leading to risk-averse behaviour, upgrading of risk factors and cessation of low-volume or poorly performing surgeons. As UK data on consultant outcome publication matures, further research is essential to ensure that high-risk patients are not inappropriately turned down for surgery.

Efficacy of ß-mannanase on broiler growth performance and energy utilization in the presence of increasing dietary galactomannan.

An experiment was conducted to investigate the impact of ß-mannanase inclusion on growth performance, viscosity, and energy utilization in broilers fed diets varying in galactomannan (GM) concentrations. Treatments were arranged as a 3 (GM concentration) × 3 (ß-mannanase inclusion) factorial randomized complete block design with 12 replicates of 29 male broilers per replicate for a 42-d experiment. Efforts were made to reduce the amount of soybean meal, and thus GM, in the basal diet with guar gum included at 0, 0.21, or 0.42% to achieve a GM supplementation of 1,500 and 3,000 ppm, respectively. Beta-mannanase was included at 0, 200, or 400 g/ton. Broilers were fed a starter (d 0 to 14), grower (d 15 to 28), and finisher diets (d 29 to 42). Growth performance was monitored and ileal contents collected on d 14, 28, and 42 to determine ileal digestible energy (IDE) and intestinal viscosity. Increasing levels of GM negatively (P < 0.05) influenced body weight (BW) following the starter and grower periods and increased (P < 0.01) mortality corrected feed conversion ratio (FCR) throughout the study. Reduced growth performance was associated with increased (P < 0.05) intestinal viscosity and decreased (P < 0.05) IDE when GM inclusion was increased. Inclusion of ß-mannanase in diets containing supplemental GM on d 28, increased average BW to levels similar to diets without supplemental GM. Improvements in FCR were also observed with ß-mannanase inclusion in diets containing supplemental GM. Ileal digestible energy was increased (P < 0.05) with the addition of ß-mannanase on d 28 of age. Multiple interactions in growth performance, intestinal viscosity, and IDE were associated with ß-mannanase administration. In conclusion, ß-mannanase improved IDE, reduced intestinal viscosity, and improved growth performance; however, the observed benefit was dependent upon dietary GM concentration.

Evaluation of increasing levels of a microbial phytase in phosphorus deficient broiler diets via live broiler performance, tibia bone ash, apparent metabolizable energy, and amino acid digestibility.

The objective was to investigate increasing concentrations of an evolved microbial phytase on male broiler performance, tibia bone ash, AME, and amino acid digestibility when fed diets deficient in available phosphorus (aP). Experiment 1 evaluated the effects of phytase during a 21 d battery cage study and Experiment 2 was a 42 d grow-out. Experiment 1 included six treatments; negative control (NC) with an aP level of 0.23% (starter) and 0.19% (grower), two positive controls (PC) consisting of an additional 0.12% and 0.22% aP (PC 1 and PC 2), and the NC supplemented with three levels of phytase (250, 500, and 2,000 U/kg). The NC diet reduced (P < 0.05) FC, BW, and bone ash. Phytase increased (P < 0.05) BW with 2,000 U/kg phytase yielding similar results to the PC2, and improved FCR and increased bone ash was observed at all phytase levels. Amino acid digestibility coefficients were increased (P < 0.05) with phytase at 250 U/kg. Phytase at all rates increased (P < 0.05) AME to levels similar level as PC diets. Linear regression analysis indicated average P equivalency values for BW and bone ash of 0.137, 0.147, and 0.226 for phytase inclusion of 250, 500, and 2000 U/kg, respectively. Experiment 2 included a PC consisting of 0.45%, 0.41%, and 0.38% aP for the starter, grower, and finisher, respectively; NC with reduced aP of 0.17%; and phytase at 500 and 2,000 U/kg. Phytase increased BW (P < 0.05) compared to the NC as 2,000 U/kg phytase resulted in further BW increases compared to the PC (starter and grower). Phytase improved FCR to levels comparable to the PC, with supplementation at 2,000 U/kg resulting in improvements beyond the PC in the starter phase. Amino acid digestibility coefficients were increased with phytase at 2,000 U/kg to levels comparable to that of the PC. These data confirm that the inclusion of phytase improves broiler performance and bone mineralization in aP reduced diets and levels beyond the traditional 500 U/kg can result in further improvements.

Heparan sulphate and the binding of lipoprotein lipase to porcine thoracic aorta endothelium.

Purified bovine milk lipoprotein lipase was shown to bind to intact porcine aortic endothelium in a specific, saturable fashion. The binding was reversed by exogenous heparin. A single class of binding sites was involved and at saturation 1.24 x 10(11) molecules of lipoprotein lipase/cm2 were bound. This represents 0.51 x 10(6) enzyme molecules per endothelial cell at a density of 1.2 x 10(3) molecules/micrometers 2. The enzyme binding was reduced by prior trypsinisation of the endothelial surface under conditions that removed cell surface glycosaminoglycan chains. The porcine endothelium was shown to have available at its surface 5.4 x 10(11) chains of heparan sulphate plus heparin-like glycosaminoglycans/cm2. Such an excess suggests that lipoprotein lipase may interact with approximately one in four of the available heparan sulphate chains.

What are appropriate end-points for Helicobacter pylori eradication in the treatment of duodenal ulcer?

The end-point of Helicobacter pylori eradication trials in peptic ulcer disease should be the presence or absence of continuing H. pylori infection, and not ulcer healing or recurrence. This is not to suggest that ulcer healing or prevention of recurrence is not the desired clinical end-point. It is to allow large trials to be conducted in a 'patient-friendly' manner and in a shorter time-scale, both of which reduce patient withdrawals, protocol violations and cost. For the same reasons, diagnosis of cure should be made by noninvasive means whenever possible. It is currently impossible to make anything other than generalisations regarding the relative efficacies of modern eradication regiments. As it seems unlikely that definitive head-to-head studies will be performed, the conduct and reporting of current trials needs to be improved and standardised, to allow meaningful comparisons. In particular, the course of each and every patient through the trial should be fully and clearly reported, especially withdrawals and dropouts. The primary efficacy analysis should be the intention-to-treat analysis, with per protocol and modified intention-to-treat analyses also reported, where appropriate.

Review article: the pharmacology of rabeprazole.

Rabeprazole sodium is a new substituted benzimidazole proton pump inhibitor with several differences compared with existing proton pump inhibitors. In vitro and animal studies have demonstrated that rabeprazole is a more potent inhibitor of H+,K(+)-ATPase and acid secretion than omeprazole, and is a more rapid inhibitor of proton pumps than omeprazole, lansoprazole, or pantoprazole. This probably reflects rabeprazole's faster activation in the parietal cell canaliculus. In human studies, once-daily doses of 5-40 mg of rabeprazole inhibit gastric acid secretion in a dose-dependent fashion. A once-daily dose of 20 mg has consistently achieved profound decreases in 24-h intragastric acidity in single and repeat dosing studies, in healthy volunteers and patients with either peptic ulcer disease or gastro-oesophageal reflux disease. Significantly greater decreases in intragastric acidity are achieved on day 1 of dosing with rabeprazole 20 mg than with omeprazole 20 mg. As with other proton pump inhibitors, rabeprazole has in vitro antibacterial activity against Helicobacter pylori, with greater activity against this organism than either lansoprazole or omeprazole. In addition to inhibiting bacterial urease activity, rabeprazole binds to several molecules on H. pylori. Clinical trials are needed to assess the clinical importance of these findings, as well as to assess whether the potential advantages of rabeprazole result in clinical benefit for patients with acid-related diseases.

The treatment of Helicobacter pylori infection.

Indications for eradication of Helicobacter pylori infection have widened since the National Institutes of Health consensus conference in 1994. It is argued that they should now include infected patients with non-ulcer dyspepsia, those concerned about the risk of gastric cancer, patients with gastric lymphoma, and those requiring long-term treatment with a proton pump inhibitor. Problems with existing clinical trials are discussed, and the results of different treatment regimens are discussed. It is proposed that future eradication trials should investigate H. pylori-infected subjects identified by serology, rather than ulcer patients, and that eradication is proved only by a pair of 13C-urea breath tests.

A placebo-controlled trial to assess the effects of 8 days of dosing with rabeprazole versus omeprazole on 24-h intragastric acidity and plasma gastrin concentrations in young healthy male subjects.

BACKGROUND: Rabeprazole (LY307640, E3810) is a new, potent, proton pump inhibitor. A single daily 20 mg dose significantly decreases 24-h intragastric acidity. There are no data currently available directly comparing the effect of rabeprazole on 24-h acidity with established proton pump inhibitors. AIM: To compare the effects of rabeprazole 20 mg o.m. and omeprazole 20 mg o.m. on 24-h intragastric acidity and plasma gastrin concentration in a randomized, double-blind, placebo-controlled trial, in healthy H. pylori-negative subjects. METHODS: Twenty-four healthy male volunteers, negative for H. pylori infection by serology and 13C-urea breath test, were studied on the 1st and 8th day of dosing with either placebo, rabeprazole 20 mg or omeprazole 20 mg, once each morning, in a crossover fashion. On days 1 and 8, hourly intragastric acidity was measured by gastric aspiration for 24 h from 08.00 hours. On day 8, plasma gastrin concentrations were also measured hourly from 08.00 to 24.00 hours, then every 2 h thereafter. RESULTS: A single dose of both rabeprazole and omeprazole significantly decreased 24-h intragastric acidity compared with placebo. The 24-h acidity on day 1 was significantly decreased for rabeprazole compared with omeprazole (331 vs. 640 mmol.h/L, P < 0.001), resulting in a significantly higher median 24-h intragastric pH and longer times at which intragastric pH was > 3 and > 4. On day 8 of dosing, the decrease in 24-h intragastric acidity was greater with rabeprazole than with omeprazole, but the difference was not statistically significant (160 vs. 218 mmol.h/L, P = 0.1). However, 24-h plasma gastrin concentration (1687 vs. 1085 pmol.h/L. P < 0.01) and percentage time that intragastric pH was > 3 (69 vs. 59%, P = 0.008) and > 4 (60 vs. 51%, P = 0.03) were significantly greater. CONCLUSIONS: Rabeprazole 20 mg once daily has a significantly faster onset of antisecretory activity than omeprazole 20 mg once daily. After 8 days the differences in intragastric pH > 3 and > 4 holding times persisted, but there was no significant difference in 24-h acidity.

Eradication of Helicobacter pylori increases nocturnal intragastric acidity during dosing with rabeprazole, omeprazole, lansoprazole and placebo.

BACKGROUND: The eradication of Helicobacter pylori decreases the antisecretory activity of omeprazole and lansoprazole. Rabeprazole is a potent proton pump inhibitor that may not be affected as greatly by H. pylori status. AIM: To compare the effect of H. pylori eradication on intragastric acidity and plasma gastrin during dosing with lansoprazole, omeprazole, rabeprazole and placebo. METHODS: Twenty-four healthy H. pylori-infected volunteers were studied on day 7 of dosing with placebo, lansoprazole 30 mg, omeprazole 20 mg and rabeprazole 20 mg, before and at least 5 weeks after H. pylori eradication. On each occasion, the 24-h intragastric acidity was measured by gastric aspiration. Plasma gastrin concentrations were measured hourly from 08.00 to 13.00 h. RESULTS: Sixteen subjects completed the study. For all three drugs and placebo, H. pylori eradication increased intragastric acidity, particularly nocturnal acidity, and decreased plasma gastrin. There were no differences between the three drugs with respect to 24-h acidity, percentage of time pH > 4 or 5-h plasma gastrin, either before or after H. pylori eradication. Before eradication, the percentage nocturnal time at pH > 3 was significantly greater during rabeprazole than during lanso-prazole dosing. CONCLUSIONS: The increase in intragastric acidity seen after H. pylori eradication during dosing with proton pump inhibitors is a drug-class effect, particularly affecting nocturnal acid control. This is related to increased spontaneous intragastric acidity after H. pylori eradication.

A placebo-controlled study to assess the effects of 7-day dosing with 10, 20 and 40 mg rabeprazole on 24-h intragastric acidity and plasma gastrin in healthy male subjects.

AIM: To compare the effects of rabeprazole 10, 20 and 40 mg o.d. on 24-h intragastric acidity and plasma gastrin concentration in a randomized, double-blind placebo-controlled trial. METHODS: Twenty-four healthy male volunteers were studied on the 7th day of morning dosing with either placebo or rabeprazole 10, 20 or 40 mg in a crossover fashion. On day 7, hourly intragastric acidity was measured for 24 h from 08.00 hours by gastric aspiration. Plasma gastrin concentrations were also measured hourly from 08.00 to 24.00 hours, and 2-hourly thereafter. RESULTS: Compared with placebo, rabeprazole 10, 20 and 40 mg produced significant dose-related decreases in intragastric acidity (median 24-h integrated acidity=697, 186, 129 and 82 mmol h/L, respectively). This was associated with significant elevation of plasma gastrin concentration (median 24-h integrated gastrin=141, 1184, 1484 and 1763 pmol.h/L, respectively). Rabeprazole 40 mg resulted in significantly decreased acidity compared with both 10 and 20 mg, and in longer times for which intragastric pH was maintained at > 3 (19. 2 h vs. 17.3 h and 17.5 h) and > 4 (17 h vs. 14.2 h and 15.2 h), but was accompanied by significantly increased plasma gastrin. There was a consistent trend for greater antisecretory activity for 20 mg compared with 10 mg, but these differences did not reach statistical significance. The interindividual variability in antisecretory response was greatest with 10 mg. CONCLUSIONS: Rabeprazole 10, 20 and 40 mg produce significant, profound dose-related inhibition of gastric acid secretion. Taking into account reciprocal increases in plasma gastrin and the interindividual variation in antisecretory response, 20 mg appears to be the preferred dose for routine clinical use.

Seven-day treatment for Helicobacter pylori infection: ranitidine bismuth citrate plus clarithromycin and tetracycline hydrochloride.

BACKGROUND: Dual therapy with ranitidine bismuth citrate plus clarithromycin twice daily for 14 days is an effective regimen for eradicating Helicobacter pylori infection. AIM: To determine whether this regimen can be improved by the addition of a second antibiotic, tetracycline hydrochloride, whilst reducing the duration of treatment to 7 days. METHODS: Sixty-one out-patients were enrolled to this open treatment study. All had H. pylori infection, as determined by 13C-urea breath test and, for those undergoing endoscopy, by rapid urease test. Patients were treated with ranitidine bismuth citrate 400 mg. clarithromycin 500 mg and tetracycline hydrochloride 500 mg all twice daily for 7 days. Eradication of H. pylori was assessed by two separate 13C-urea breath tests, the first 28-68 days after the completion of treatment, the second 28-162 days later. H. pylori infection was considered cured if both tests were negative. RESULTS: All 61 patients were included in the intention-to-treat efficacy analysis. Successful eradication of H. pylori was achieved in 55/61 patients (90%; 95% CI; 82-98%). Fifty-nine out of sixty-one patients reported 100% compliance; one patient missed a single dose of medication and the other withdrew at 48 h due to nausea and vomiting. Minor adverse events were reported by 30/61 patients. CONCLUSION: One-week triple therapy with ranitidine bismuth citrate, clarithromycin and tetracycline, all twice daily, is a safe and well-tolerated regimen which eradicates H. pylori in 90% of infected patients.

The effect of omeprazole dosing on the isolation of Helicobacter pylori from gastric aspirates.

BACKGROUND: Animal experiments suggest that omeprazole dosing increases shedding of Helicobacter into the gastric lumen, and hence into gastric juice. AIM: To assess the effect of omeprazole dosing on the yield of H. pylori from gastric aspirates of infected volunteers. METHODS: Six serial nasogastric aspirates, three before and three during dosing with omeprazole 40 mg b.d., were obtained for culture from 10 H. pylori infected volunteers and one uninfected volunteer. To reduce contamination, samples were diluted 1:10 with Maximum Recovery Diluent (MRD; pH 7.0) or HCl-KCl buffer (pH 2.2) prior to culture on Columbia and Dent's agar. RESULTS: Undiluted gastric juice cultures were rapidly overgrown by upper respiratory tract flora. HCl-KCl dilution resulted in isolation of H. pylori from 77% of infected subject aspirates before, and 67% of aspirates during dosing with omeprazole. The yields were significantly lower with MRD dilution, 47% and 10%, respectively. Omeprazole dosing significantly decreased the yield after MRD dilution, but not after HCl-KCl dilution. CONCLUSIONS: Decreasing intragastric acidity, by dosing with omeprazole, decreases the isolation of H. pylori from routinely processed gastric aspirates. In vitro acidification of gastric aspirates, by HCl-KCl dilution, increases the isolation of H. pylori both before and during omeprazole dosing.