Laparoscopic peritoneal lavage for generalized peritonitis due to perforated diverticulitis

BACKGROUND

The standard approach to generalized peritonitis due to perforated diverticulitis involves open surgery and diversion of faecal content. This study assessed the feasibility of laparoscopic peritoneal lavage.

METHODS

A prospective multi-institutional study of 100 patients was undertaken. All consenting patients with perforated diverticulitis causing generalized peritonitis underwent attempted laparoscopic peritoneal lavage. The degree of peritonitis, according to the Hinchey grading system, was recorded. Primary endpoints were operative success and resolution of symptoms.

RESULTS

Patients had a median age of 62.5 (range 39-94) years, a male : female ratio of 2 : 1 and a median American Society of Anesthesiologists grade of III (range II-V). Eight patients with grade 4 diverticulitis had conversion to an open Hartmann's procedure. The remaining 92 patients were managed by laparoscopic lavage, with morbidity and mortality rates of 4 and 3 per cent respectively. Two patients required postoperative intervention for a pelvic abscess. Only two patients re-presented with diverticulitis at a median follow up of 36 (range 12-84) months.

CONCLUSION

Laparoscopic management of perforated diverticulitis with generalized peritonitis is feasible, with a low recurrence risk in the short term.

Survey of Salmonella contamination of raw shell eggs used in food service premises in the United Kingdom, 2005 through 2006

This survey was launched after an unusual number of Salmonella Enteritidis outbreaks associated with the use of eggs in food service premises in England and Wales. Between November 2005 and December 2006, 9,528 eggs (1,588 pooled samples of 6 eggs) were collected from 1,567 food service premises in the United Kingdom, most of which (89%) were produced in the United Kingdom. Salmonella was isolated from 6 (0.38%) pools of eggs. Of these, 5 (0.31%) were Salmonella Enteritidis, which were further characterized to phage types (PTs): PT 4 (0.19%), PT 8 (0.06%), and PT 12 (0.06%). Salmonella Mbandaka was also isolated (0.06%). Salmonella was detected from five and one of pooled eggs samples that were produced in the United Kingdom and Germany, respectively; these were from different producers. The study showed evidence of poor egg storage and handling practices in food service premises, in that 55% did not store eggs under refrigerated conditions; 20.7% of eggs had expired "best before" dates or were in use after 3 weeks of lay, indicating poor stock rotation; and 37.1% pooled eggs not intended for immediate service. Eggs are a commonly consumed food that may occasionally be contaminated with Salmonella at different rates, according to their country of origin. The food service sector needs to be aware of this continuing hazard, receive appropriate food safety and hygiene training on storage and usage of raw shell eggs, adopt appropriate control measures, and follow advice provided by national food agencies in order to reduce the risk of infection.

Increasing analytical space in gas chromatography-differential mobility spectrometry with dispersion field amplitude programming

Enhancing the analytical space of differential mobility spectrometry with dispersion field amplitude programming was proposed. Six volatile organic compound candidate breath markers, 1,3-butanediol, butanone, ethylbenzene, heptan-2-one, nonanal, and o-xylene were used to characterise the effect of programming the amplitude of the dispersion field on the sensitivity, and resolution of the responses observed. Sensitivity followed two patterns of behaviour. Sensitivity to heptan-2-one and 1,3-butanediol increased to a maximum at approximately 20 kV cm(-1), attributed to dissociative ionisation effects. The remaining four compounds' responses were dominated by wall-loss phenomena resulting in a constant reduction in sensitivity as dispersion field amplitude was increased. The effect of the dispersion field on analytical space was pronounced. At a field strength of 18 kV cm(-1) protonated monomers and proton-bound dimers could be observed within the chromatographic responses for the carbonyl compounds. Dissociative ionisation products were also discerned for 1,3-butanediol and butanone. The ion chemistry of the two hydrocarbons was not affected by the dispersion field amplitude. Resolution of the product ions and their separation from the reactant ion peaks increased significantly with increasing dispersion field amplitude. With a range of behaviours observed. Peak resolutions increased from the range 0 to 1.2 to 1.2 to 7, while resolving power increased from 0 (at low dispersion field amplitudes) to the range 0.2-6 at 20-24 kV cm(-1). The effect of programming the dispersion field amplitude on a "real-life" application was demonstrated with replicate breath samples obtained from a subject with chronic obstructive pulmonary disease.

Bevacizumab, a vascular endothelial growth factor (VEGF) specific antibody reduces interstitial fluid pressure (IFP) in human rectal cancer xenograft (HT29) by day 5: Is this evidence for rescheduling its timing relative to chemotherapy?

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Background: Interstitial fluid pressure (IFP) of most solid tumours is increased relative to normal tissues; this is thought to be associated with the development of structurally and functionally abnormal blood and lymphatic vessels and interstitial fibrosis. Such interstitial hypertension creates a barrier for tumour transvascular transport, consequently compromising the delivery and efficacy of chemotherapy. We investigated the effect of Bevacizumab on IFP of a human rectal cancer xenograft. Methods: SCID mice bearing subcutaneous HT29 tumours of =8.5 mm diameter received a single dose of 10 mg/kg Bevacizumab intraperitoneally; controls received saline. Tumour IFP was measured in sedated mice (Hypnorm) on days 1, 3 and 5 post injection, using the wick-in-needle technique. Experiments were conducted under Home Office licence and approved by the local ethical committee. Results: Groups of 8 treated and control tumours were examined on days 1, 3 and 5 (n = 48). IFP was significantly lower (p<0.0001) on day 5 in treated than control tumours (mean ± SD 15.1 ± 4.7 cf 36.9 ± 5.6 mm Hg). No significant differences (p>0.05) between treated and control groups were seen on day 1 (31.8 ± 3.5 cf 30.6 ± 3.1 mm Hg) or day 3 (33.4 ± 5.5 cf 31.5 ± 3.2 mm Hg). No data were acquired on day 7 as the tumours ulcerated. Conclusions: Our data show that Bevacizumab causes a significant reduction of tumour IFP, but not until 5 days after treatment. Reduced IFP could augment uptake of cytotoxic drugs into tumour cells, hence timing of Bevacizumab relative to the first dose of chemotherapy could be of critical importance.

No significant financial relationships to disclose.

An adaptive breath sampler for use with human subjects with an impaired respiratory function

An adaptive sampler for collecting 2.5 dm(3) samples of exhaled air from human subjects with an impaired respiratory function is described. Pressure in the upper respiratory tract is continuously monitored and the data used to control an automated system to collect select portions of the expired breathing cycle onto a mixed bed Tenax(trade mark) and Carbotrap(trade mark) adsorbent trap for analysis by GC-MS. The sampling approach is intended for use in metabolomic profiling of volatiles in human breath at concentrations greater than microg m(-3). The importance of experimental reproducibility in metabolomic data is emphasised and consequently a high purity air supply is used to maintain a stable exogenous volatile organic compound profile at concentrations in the range 5 to 30 microg m(-3). The results of a 90 day stability study showed that exogenous VOCs were maintained at significantly lower levels (40 times lower for isopropyl alcohol) and with significantly higher reproducibility (80 times lower standard deviation for isopropyl alcohol) than would have been be the case if ambient air had been used. The sampling system was evaluated with healthy controls alongside subjects with chronic obstructive pulmonary disease. Subjects were able to breathe normally with control subjects observed to breathe at a rate of 9 to 17 breaths per minute, compared to 16 to 30 breaths per minute for subjects with COPD. This study presents, for the first time, observations and estimates of intra-subject breath sample reproducibility from human subjects. These reproducibility studies indicated that VOCs in exhaled breath exhibit a variety of dynamic behaviours, with some species recovered with a RSD <30%, while other species were observed to have significantly more variable concentrations, 30 to 130% RSD. The approach was also demonstrated to reliably differentiate the differences in the VOC profiles between alveolar and dead space air.

Antimicrobial resistance in non-typhoidal salmonellas from humans in Northern Ireland, 2001-2003: standardization needed for better epidemiological monitoring

This study investigated the identification and antimicrobial susceptibility testing of Salmonella isolates in Northern Ireland during 2001-2003. All six participating hospital laboratories used similar methods. Identification and antimicrobial resistance of human enteric (n=897) Salmonella isolates were analysed by retrospective collation of laboratory records. Resistance of human Salmonella isolates to nalidixic acid was 16% but resistance to ciprofloxacin or cefotaxime was rare (<1%). Minor inter-laboratory variations in sensitivity testing practices make it difficult to compare antimicrobial sensitivity results reliably and also to monitor for epidemic clones such as S. Typhimurium DT104 with the ACSSuT resistance pattern. The outcome of this study was the adoption of a standardized regional approach to the isolation of salmonella antimicrobial resistance. This should improve epidemiological monitoring of epidemic clones and assure optimum treatment options are available. In cases of treatment failure, MICs to third-generation cephalosporins and ciprofloxacin should be determined.

The endothelin B (ETB) receptor agonist IRL 1620 is highly vasoconstrictive in two syngeneic rat tumour lines: potential for selective tumour blood flow modification

The vascular effects of the endothelin B (ET_B) receptor agonist IRL 1620 were investigated in the rat P22 carcinosarcoma and a range of normal tissues in BDIX rats. Tissue blood flow rate was calculated from measurements of tissue uptake of radiolabelled iodoantipyrine. A comparison of vascular effects in the P22 tumour and the HSN sarcoma growing in CBH/CBi rats was made using laser Doppler flowmetry, showing similar effects of IRL 1620, with red cell flux rapidly decreasing by 50–60% and then returning to control levels within approximately 30 min. This corresponded to similar levels but different spatial organisation of ET_B binding sites in the two tumours, as measured by autoradiography. The decrease in tumour blood flow and an increase in vascular resistance suggest that the vascular component of ET_B receptors in the P22 tumour is localised on contractile elements rather than on endothelial cells. ET_A receptors were also identified. Vasoconstriction occurred uniformly throughout the P22 tumour mass, consistent with a measured homogeneous distribution of ET_B receptors. IRL 1620 caused vasoconstriction in normal skeletal muscle, kidney and small intestine of the BDIX rat as well as in tumour, but did not affect blood flow in other tissues. These effects could be useful for limiting toxicity of certain chemotherapeutic agents. Fully functional ET_B receptors are clearly expressed on tumour vasculature and IRL 1620 shows promise for short-term modification of tumour blood flow. Expression levels of ET_B receptors on the tumour vasculature could be useful for predicting which tumours are likely to respond to IRL 1620.

Development of a capture/enrichment sandwich ELISA for the rapid detection of enteropathogenic and enterohaemorrhagic Escherichia coli O26 strains

AIMS

To improve the sensitivity of a monoclonal antibody (MAb 2F3) based enteropathogenic Escherichia coli (EPEC)/enterohaemorrhagic E. coli (EHEC) serogroup O26-specific sandwich ELISA (sELISA), using a capture/enrichment format of the assay.

METHODS AND RESULTS

The sELISA utilized an EPEC/EHEC O26-specific MAb 2F3 as the capture reagent and an E. coli serogroup O26 lipopolysaccharide-specific polyclonal antibody in the development stage. Wells containing faeces test samples from bovine enteritis cases and agar colony sweep cultures from human diarrhoea cases, after a 2-h capture stage, were washed and enrichment of the captured cells was encouraged by addition of tryptone soya broth. After overnight incubation, the contents of each well were transferred to sterile wells and the sELISA completed. Any sELISA positive samples were then subcultured onto blood agar to recover and further characterize the positive cultures. The assay had a sensitivity of 10(3) CFU ml(-1). ELISA positive samples consisted of 21 (4.8%) of the 442 bovine and 19 (3.7%) of the 519 human samples tested, and ELISA positive EPEC/EHEC O26 strains were isolated from 11 and three of these samples respectively.

CONCLUSION

The capture/enrichment method improved the sensitivity of a MAb-based sELISA for the detection of EPEC/EHEC O26 strains, and also contributed to an improved isolation rate of the organism from field samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

The application of a specific MAb in a capture/enrichment format of the sELISA, provides a prospectively suitable screening method for the detection of pathogenic bacteria from mixed culture samples.

A pilot investigation of the hypoalgesic effects of transcutaneous electrical nerve stimulation upon low back pain in people with multiple sclerosis

OBJECTIVE

To investigate the hypoalgesic effects of transcutaneous electrical nerve stimulation (TENS) upon low back pain (LBP) in people with multiple sclerosis (MS).

DESIGN

A randomized double-blind placebo controlled clinical pilot study.

SUBJECTS AND SETTING

Fifteen people with MS were recruited and randomly allocated to one of the following groups under double blind conditions (n = 5 per group): TENS 1 (4 Hz, 200 micros), TENS 2 (110 Hz, 200 micros), placebo TENS.

INTERVENTIONS

Treatment was applied for 45 minutes three times a week for six weeks with a four-week follow-up.

OUTCOME MEASURES

The following outcome measures were taken at weeks 1, 6, and 10: visual analogue scale (VAS) (for current LBP, right leg pain, left leg pain); Leeds Multiple Sclerosis Quality of Life Questionnaire; Roland Morris Disability Questionnaire; Short Form-36 (SF-36) Version 1; and the McGill Pain Questionnaire (MPQ). VAS for current LBP, right and left leg pain were also taken before and after treatment, and once a week during the follow-up period.

RESULTS

Analysis showed no statistically significant effects for any of the data. However, both active treatment groups showed a trend of improvement in the majority of the outcome measures.

CONCLUSION

Active TENS was more effective than placebo TENS in decreasing VAS scores following each treatment although results were not statistically significant. Further work in this area is warranted and should include a larger number of participants in the form of a randomized controlled clinical trial to determine the efficacy of this modality.

Frequency and temperature dependence of electrical breakdown at 21, 30, and 39 GHz

A TeV-range e(+)e(-) linear collider has emerged as one of the most promising candidates to extend the high energy frontier of experimental elementary particle physics. A high accelerating gradient for such a collider is desirable to limit its overall length. Accelerating gradient is mainly limited by electrical breakdown, and it has been generally assumed that this limit increases with increasing frequency for normal-conducting accelerating structures. Since the choice of frequency has a profound influence on the design of a linear collider, the frequency dependence of breakdown has been measured using six exactly scaled single-cell cavities at 21, 30, and 39 GHz. The influence of temperature on breakdown behavior was also investigated. The maximum obtainable surface fields were found to be in the range of 300 to 400 MV/m for copper, with no significant dependence on either frequency or temperature.

Influence of sex and Helicobacter pylori on development and healing of gastroduodenal lesions in non-steroidal anti-inflammatory drug users

BACKGROUND AND AIMS

Factors predisposing to endoscopic ulcer formation or healing with non-steroidal anti-inflammatory drugs (NSAIDs) have not been well defined.

METHODS

We used multivariate analysis of data from three large similar trials to identify factors associated with endoscopic lesions and healing. We compared the effectiveness of omeprazole 20 mg and 40 mg daily, misoprostol 200 micro g four times daily, and ranitidine 150 mg twice daily in healing ulcers and erosions at different sites and in patients who were Helicobacter pylori positive and negative.

RESULTS

Older age, past ulcer history, rheumatoid arthritis, and H pylori infection were significantly associated with ulcers. Duodenal ulcer was significantly more likely than gastric ulcer with a past ulcer history (odds ratio 1.59, 1.16-2.17), H pylori infection (1.4, 1.04-1.92), and male sex (2.35, 1.75-3.16) while female sex, older age (> or = 60 years: 1.39, 1.03-1.88), and higher NSAID dose (>1 defined daily dose: 1.57, 1.16-2.14) were associated with gastric ulceration. Sex differences were seen in both H pylori positive and negative patients. Gastric and duodenal ulcer healing was significantly faster with omeprazole 20 mg than with misoprostol 200 micro g four times daily or ranitidine 150 mg twice daily although misoprostol was more effective at healing erosions. Gastric ulcer healing was slower with large ulcers (0.37, 0.25-0.54 for >10 mm v 5-10 mm) or a past ulcer history (0.51, 0.34-0.76), and faster with H pylori infection (1.55, 1.06-2.29), especially with acid suppression (72% v 37% at four weeks with ranitidine).

CONCLUSIONS

Among NSAID users, H pylori and male sex independently increase the likelihood of duodenal ulceration. H pylori infection does not affect duodenal ulcer healing and enhances gastric ulcer healing by ranitidine and possibly other acid suppressing treatments.

Relative contribution of mucosal injury and Helicobacter pylori in the development of gastroduodenal lesions in patients taking non-steroidal anti-inflammatory drugs

BACKGROUND AND AIMS

A past history of peptic ulceration increases the risk of an ulcer developing during non-steroidal anti-inflammatory drug (NSAID) use. Whether this is due to Helicobacter pylori infection or to reactivation of the original lesion is unclear.

METHODS

We used multivariate regression analyses of three large similar trials to identify factors that placed patients at high risk of ulcer development or relapse. We compared the efficacy of omeprazole 20 mg daily, misoprostol 200 micro g twice daily, and ranitidine 150 mg twice daily in preventing ulcers and erosions at different sites and in patients who were H pylori positive and negative.

RESULTS

Patients with endoscopic lesions (which healed) initially were significantly more likely than those without to develop further erosions or ulcers during treatment (rate ratio 2.12, 1.07-4.17). Risk mounted further with ulcers versus erosions, particularly those that had been slow to heal. There was a highly significant tendency for the relapse lesion to replicate the site and type of the original lesion (mean odds ratios ranging from 3 to 14). Treatment failure was significantly less likely with omeprazole than with placebo, misoprostol, or ranitidine. This advantage was especially evident in H pylori positive patients receiving acid suppression (5.7% v 16.6% for gastric ulcer with omeprazole).

CONCLUSIONS

Relapse of lesions in patients taking NSAIDs was highly site and type specific and not adversely affected by H pylori status. This strongly implies that local mucosal factors predispose to ulcer development in patients taking NSAIDs. Identification of the responsible mucosal changes would aid understanding and could promote better treatment.