Metabolic-associated fatty liver disease and hepatocellular carcinoma: a prospective study of characteristics and response to therapy

BACKGROUND AND AIM

The rising incidence of hepatocellular carcinoma (HCC) in Australia is related to increasing rates of metabolic-associated fatty liver disease (MAFLD). This study aimed to prospectively characterize the metabolic profile, lifestyle, biometric features, and response to treatment of HCC patients in an Australian population.

METHOD

Multicenter prospective cohort analysis of newly diagnosed HCC patients at six multidisciplinary team meetings over a 2-year period.

RESULTS

Three hundred and thirteen (313) newly diagnosed HCC patients with MAFLD (n = 77), MAFLD plus other liver disease (n = 57) (the "mixed" group), and non-MAFLD (n = 179) were included in the study. Alcohol-associated liver disease (ALD) (43%) and MAFLD (43%) were the most common underlying liver diseases. MAFLD-HCC patients were older (73 years vs 67 years vs 63 years), more likely to be female (40% vs 14% vs 20%), less likely to have cirrhosis (69% vs 88% vs 85%), showed higher ECOG, and were less likely to be identified by screening (29% vs 53% vs 45%). Metabolic syndrome was more prevalent in the MAFLD and mixed groups. The severity of underlying liver disease and HCC characteristics were the same across groups. While the MAFLD population self-reported more sedentary lifestyles, reported dietary patterns were no different across the groups. Dyslipidemia was associated with tumor size, and those taking statins had a lower recurrence rate.

CONCLUSION

Equal to ALD, MAFLD is now the most common underlying liver disease seen in HCC patients in Australia. Future HCC prevention screening and treatment strategies need to take this important group of patients into consideration.

O102 We know about left gastric artery embolisation and will embio provide the next solution to treat obesity?

Introduction

Left gastric artery embolisation (LGAE) is a minimally invasive procedure which has shown promising results for weight loss in recent studies and could play a key role as a treatment option in-between our current tier-3 and tier-4 services. Imperial College NHS Trust will sponsor the EMBIO trial, the first multi-centre double blinded randomised controlled trial comparing LGAE vs Placebo procedure to evaluate its efficacy on weight loss and obesity related comorbidities over a 12 month follow up period. Here, we perform a systematic review of the existing literature.

Methods

9 studies were reviewed. Studies which investigated weight loss as a % +- Ghrelin % change at 3,6 and 12 months were included as these pre-defined time points correlate with the EMBIO protocol. 6 studies met our inclusion criteria, 5 single arm studies and 1 single blinded RCT.

Results

N=62 patients were included in our analysis. Mean weight loss reported was 8.5%, 8.8% and 10% at 3, 6 and 12 months respectively post LGAE. Ghrelin levels reduced by 36%, 16.2% and 16.5% at 3, 6 and 12 months respectively post LGAE. To date, the only reported adverse events recorded include superficial gastric erosions healed on endoscopy by day 90 and one case of subclinical pancreatitis.

Conclusion

LGAE potentially offers a day case procedure under local anaesthesia and sedation to treat obesity and its metabolic complications. The EMBIO trial will provide level 1 evidence to confirm if LGAE is a viable intervention for obesity and evaluate its safety profile.

Take-home message

Left gastric artery embolisation could be the perfect solution to treat obesity in between existing tier-3 and tier-4 treatments.

An evaluation of the feasibility and validity of a patient-administered malnutrition universal screening tool ('MUST') compared to healthcare professional screening in an inflammatory bowel disease (IBD) outpatient clinic

BACKGROUND

Malnutrition is common in inflammatory bowel disease (IBD) and is associated with poor health outcomes. Despite this, screening for malnutrition in the outpatient-setting is not routine and research in the area is limited. The present study aimed to evaluate whether agreement between malnutrition screening completed by patients and healthcare professionals (HCPs) could be achieved by comparing patient self-administered 'MUST' ('MUST'-P) with HCP administered 'MUST' ('MUST'-HCP) in a single tertiary IBD outpatient clinic.

METHODS

We conducted a feasibility and validity study on adult outpatients with IBD. We collected anthropometric, nutritional and clinical data from patients. All patients completed 'MUST'-P using a self-administered questionnaire, followed by 'MUST'-HCP. 'MUST'-P was timed and feedback on ease-of-use was obtained. The risk of malnutrition was classified as low (score = 0), medium (score = 1) and high (score ≥ 2) and agreement was tested using kappa statistics (κ).

RESULTS

Eighty patients were recruited (Crohn's disease: n = 49, ulcerative colitis: n = 29, unclassified: n = 2), with a mean (SD) age of 39.9 (15.1) years (51.2% were males). Seventy-one (92%) of patients found 'MUST'-P either easy or very easy. The mean (SD) time to complete 'MUST'-P was 3.1  (1.8) min (range 1-10 min). Sixty-eight (85%) of patients were at low risk of malnutrition when screened by the HCP. There was moderate agreement (κ = 0.486, P < 0.001) between 'MUST'-P and 'MUST'-HCP, with 100% agreement in scoring for medium- and high-risk categories.

CONCLUSIONS

The results of the present study suggests that self-screening using 'MUST' could be effectively used in an IBD outpatient clinic to identify those at medium and high risk of malnutrition. The patient friendly version of 'MUST' ('MUST'-P) was considered quick and easy to use by patients. Implementation of self-screening with 'MUST' could improve the nutritional management of IBD patients.

Seasonal recurrence of food bolus obstruction in eosinophilic esophagitis

BACKGROUND

Eosinophilic esophagitis (EoE) is a newly recognised condition that is apparently increasing in prevalence, and the aetiology is poorly understood. The role of aeroallergens in EoE is controversial, given the success of dietary therapy. Massive aeroallergen exposure leading to food bolus obstruction events (FBOE) has been described, and the diagnosis of EoE by esophageal biopsy noted to be more common in the pollen season according to previous case series.

AIM

To determine if a seasonal variation and a geographical variation occurred in EoE presenting as FBOE in adults, and to track the prevalence of FBOE and EoE over time.

METHOD

A retrospective case-control study analysis was performed from January 2002 to January 2012 to identify all FBOE in adults presenting to five tertiary hospitals in Melbourne, Australia. Endoscopy, histopathological reports, case notes and blood tests were examined, and postcodes recorded. Records of pollen counts were obtained. Cases were defined according to esophageal biopsy and grouped based on month of diagnosis. All other causes of FBOE served as controls.

RESULTS

One thousand, one hundred and thirty-two FBOE were identified. Biopsies were only performed in 278 of these cases, and 85 patients were found to have EoE after biopsy. Patients with EoE were younger (mean age 38 years, range 18-72) compared with those with alternative diagnosis (mean age 64.4 range 22-92), more likely to be male (M : F = 4:1 compared with 1.68:1 ) and had a higher eosinophil count in venous blood. Overall no seasonality was demonstrated in FBOE secondary to any diagnosis, although the six cases of recurrent FBOE secondary to EoE mainly occurred in the grass pollen season in subsequent years. FBOE cases were evenly distributed throughout metropolitan Melbourne irrespective of population density. EoE as a percentage of FBOE increased over time.

CONCLUSION

Seasonal aeroallergens may be important for a subgroup of patients with EoE presenting as recurrent FBOE. Esophageal biopsies are performed in a minority of patients, representing a significant departure from ideal management and contributing to recurrent unnecessary FBOE. EoE is an increasingly important cause of FBOE.

Identification of Risk Factors for Cervical Spine Injury from Pediatric Trauma Registry

BACKGROUND

Cervical spine injuries are rare in children. Our goal is to establish guidelines for cervical spine clearance that are practical for our pediatric population, and, in the process, to reduce the risk of radiation exposure from unnecessary advanced imaging.

METHODS

We retrospectively reviewed the records from the registries of two pediatric trauma centers from the past 11 years (January 2002 to June 2013). Patients aged 1 month to 17 years, who had a CT scan of the cervical spine due to trauma indication for possible cervical spine injury, were evaluated.

RESULTS

Three risk factors were identified as being significant for the presence of a cervical spine injury. Patients who sustained a cervical spine injury were more likely to be male (p = 0.0261), were more severely injured with a higher injury severity score (ISS 16.39 ± 15.79 injured vs. 8.7 ± 9.4 uninjured), and presented with neck tenderness (p = 0.0001).

CONCLUSION

In our study, significant cervical spine injury is related to male gender, higher ISS and neck tenderness.

Systematic review with meta-analysis: endoscopic balloon dilatation for Crohn's disease strictures

BACKGROUND

Endoscopic balloon dilatation (EBD) is recognised treatment for symptomatic Crohn's strictures. Several case series report its efficacy. A systematic analysis for overall efficacy can inform the design of future studies.

AIM

To examine symptomatic (SR) and technical response (TR) and adverse events (AE) of EBD. Stricture characteristics were also explored.

METHODS

A systematic search strategy of COCHRANE, MEDLINE and EMBASE was performed. All original studies reporting outcomes of EBD for Crohn's strictures were included. SR was defined as obstructive symptom-free outcome at the end of follow-up, TR as post-dilatation passage of the endoscope through a stricture, and adverse event as the presence of complication (perforation and/or bleeding). Pooled event rates across studies were expressed with summative statistics.

RESULTS

Twenty-five studies included 1089 patients and 2664 dilatations. Pooled event rates for SR, TR, complications and perforations were 70.2% (95% CI: 60-78.8%), 90.6% (95% CI: 87.8-92.8%), 6.4% (95% CI: 5.0-8.2) and 3% (95% CI: 2.2-4.0%) respectively. Cumulative surgery rate at 5 year follow-up was 75%. Pooled unweighted TR, SR, complication, perforation and surgery rates were 84%, 45%, 15%, 9% and 21% for de novo and 84%, 58%, 22%, 5% and 32% for anastomotic strictures. Outcomes between two stricture types were no different on subgroup meta-analysis.

CONCLUSIONS

Efficacy and complication rates for endoscopic balloon dilatation were higher than previously reported. From the few studies with 5 year follow-up the majority required surgery. Future studies are needed to determine whether endoscopic balloon dilatation has significant long-term benefits.

Pretreatment neutrophil/lymphocyte ratio is superior to platelet/lymphocyte ratio as a predictor of long-term mortality in breast cancer patients

The aim of our study was to assess the predictive value of platelet/lymphocyte ratio (PLR) and neutrophil/lymphocyte ratio (NLR) in terms of survival in breast cancer patients. This is an observational study of 437 breast cancer patients treated between January 2004 and December 2006. Survival status was obtained from our cancer registry and Social Security Death Index. Survival analysis, stratified by NLR and PLR quartiles, was used to evaluate their prognostic values. Patients in the highest 4th PLR and NLR quartiles had higher 5-year mortality rate (30.4 and 40.3 %) compared to those in the lower three PLR and NLR quartiles (12.1 and 8.2 %), p < 0.0001. Multivariate hazard ratios of 4th PLR and NLR quartiles compared to first PLR and NLR quartiles were 3.68 (1.74-7.77, p = 0.001) and 3.67 (1.52-8.86, p = 0.004). Higher PLR only showed a trend of higher mortality in patients with normal lymphocyte count, whereas NLR continued to be statistically significant predictor of 5-year mortality in all lymphocyte count subsets. Pretreatment NLR is an independent predictor of long-term mortality in breast cancer patients, whereas pretreatment PLR was not superior to absolute lymphocyte count alone in predicting long-term mortality.

Quantitative MRI of colonic mural enhancement: segmental differences exist in endoscopically proven normal colon

OBJECTIVES

Abnormal contrast enhancement on MRI is advocated as a biomarker for inflammation in colitis, although the enhancement kinetics of normal colon are poorly described. Our purpose was to quantitatively assess mural enhancement in normal colon and test for intersegmental differences.

METHODS

Eight patients without prior history of inflammatory bowel disease underwent standard MRI colonography followed by normal same-day colonoscopy. Acquired sequences included a volumetric interpolated breath-hold examination (VIBE) to encompass the whole colonic volume, performed at 5°, 10° and 35° flip angles for T(1) quantitation and then at a fixed 35° flip angle three times prior to and every 30 s following intravenous gadoterate meglumine for 220 s. Ascending colon, descending colon and rectal R(1) (1/T(1)) was plotted against time. Mean pre-contrast R(1), initial change of R(1) (ΔR(1)), early and late "plateau phase" enhancement and the area under the R(1)-time (AUC-R(1)) curve were compared between segments using the Student's paired t-test.

RESULTS

There was no significant difference of pre-contrast R(1) between segments (p=0.49 to 0.62). ΔR(1) was higher for ascending colon compared with descending colon (0.0023±0.0012 ms(-1) vs 0.0010±0.0011 ms(-1), p=0.03). There was no significant difference for early or late plateau phase R(1) between colonic segments (p=0.08 to 1.00). AUC-R(1) was greater for ascending than descending colon (0.54±0.19 vs 0.30±0.14, p=0.03).

CONCLUSIONS

Intersegmental differences in colonic enhancement are present and should be considered when interpreting differential segmental enhancement.

MRI enterography: what is the clinical impact of unsuspected extra-enteric findings?

To define the incidence and nature of incidental extra-enteric findings on magnetic resonance enterography (MRE) following the introduction of a new clinical service, to assess the volume of additional tests generated and to gauge the potential of MRE to reduce the need for subsequent abdominal imaging. The imaging and patient records of 500 consecutive patients undergoing MRE at a single institution were reviewed. Note was made of patient demographics, any extra-enteric findings reported on the MRE, whether additional tests were recommended by the reporting radiologists to clarify or follow up extra-enteric findings and whether the patients underwent additional abdominal or pelvic imaging in the 4 months after the MRE. 64% of the cohort was male. The mean age was 45 years (range 11-80 years). Overall 190 (38%) underwent MRE for assessment of known Crohn's disease and 310 (62%) for other indications, such as abdominal pain and anaemia. 26 non-bowel-related extra-enteric abnormalities were noted on the MRE report in just 15 patients (3%), and a total of 6 additional tests were recommended by the reporting radiologist. 13 patients (2.6%) underwent some form of abdominal imaging within 4 months of the MRE. None of these additional investigations revealed any abnormality missed on the MRE. Extra-enteric findings are unlikely to have a significant impact on healthcare resources after the introduction of an MRE service.

CCK, PYY and PP: the control of energy balance

The control of food intake consists of neural and hormonal signals between the gut and central nervous system (CNS). Gut hormones such as CCK, PYY and PP signal to important areas in the CNS involved in appetite regulation to terminate a meal. These hormones can act directly via the circulation and activate their respective receptors in the hypothalamus and brainstem. In addition, gut vagal afferents also exist, providing an alternative pathway through which gut hormones can communicate with higher centres through the brainstem. Animal and human studies have demonstrated that peripheral administration of certain gut hormones reduces food intake and leads to weight loss. Gut hormones are therefore potential targets in the development of novel treatments for obesity and analogue therapies are currently under investigation.

Patient experiences of MR colonography and colonoscopy: a qualitative study

OBJECTIVES

The aim of this study was to apply qualitative techniques to assimilate data on patient experience and attitudes during MR colonography (MRC) and colonoscopy (CC).

METHODS

18 patients (11 male, 8 female, median age 40.5 years), 10 of whom had known colonic inflammatory bowel disease (IBD) and 8 who were under investigation for suspected colonic neoplasia (non-IBD), underwent MRC and conventional CC. Semi-structured interviews were performed to assimilate test experiences and preferences, and themes were extracted using thematic analysis.

RESULTS

Thematic analysis identified three main themes: (i) physical experience, (ii) information provision and (iii) overall preference. Patients expressed mixed views about the physical experience of MRC but specifically identified water filling, breath holding and lying still as problematic. Anxiety was expressed regarding potential incontinence. Scanner noise interfered with the understanding of instructions, particularly amongst non-IBD patients. Non-IBD patients expressed greater anxiety over the delay in receiving the MRC report than IBD patients. In general MRI was considered as the more informative and safer investigation. Patients reported more physical discomfort during CC (notably IBD patients) related to air insufflation and colonoscopic manipulation but were more satisfied with the feedback they received. 10 patients (56%) stated an overall preference for MRC and 5 (28%) preferred CC. Reasons for preferences stated by the patients included discomfort, speed of the test, safety, perceived diagnostic ability and the ability to take biopsies.

CONCLUSION

Experiences of MRC and CC are complex and influenced by clinical indication. Individuals place different weightings on the relative importance of test attributes including discomfort, noise, immobility, feedback, safety and fear of incontinence and this defines overall preference.

Diagnostic and therapeutic impact of MR enterography in Crohn's disease

AIM

To assess the impact of magnetic resonance enterography (MRE) on clinician diagnostic confidence and therapeutic strategy in patients under investigation for small bowel Crohn's disease.

MATERIAL AND METHODS

Gastroenterologists completed a proforma before and following MRE in 51 patients (mean age 35 years, 26 female) under investigation for small bowel Crohn's disease, indicating percentage confidence for presence/absence of small bowel involvement. In suspected disease, diagnostic confidence (using a scoring system from 1=no to 6=yes) was scored for subcategories: extent >30 cm (DE), terminal ileum (lTI), jejunal (JD), colonic disease (CoD), strictures (ST), activity (AD), extraluminal complications (EL), and surgical need (NS). Therapeutic strategy was recorded. Patients were divided into three groups: 1=suspected disease, MRE normal (n=15); 2=suspected disease, MRE abnormal (n=30); 3=no suspected disease, MRE normal (n=6). Binomial exact and paired t-tests were use to compare confidence pre and post-MRE.

RESULTS

Mean percentage confidence for the presence/absence of small bowel disease increased from 62 to 84% (p=0.003), 87 to 98% (p=0.0001), and 83 to 98% (p=0.005) after MRE for groups 1, 2, and 3, respectively. In suspected disease, confidence changed significantly for all of the subcategories (p<0.001) except EL in group 1. The percentage of patients with a confidence change ranged from 40% (CoD) to 87% (lTI; group 1) and from 7% (EL) to 93% (DE; group 2). Therapeutic strategy changed in 31/51 (61%, 95% CI 47-74%), 14 with a reduction in planned therapy and 17 with an increase.

CONCLUSION

MRE had a positive diagnostic impact in patients under investigation for small bowel Crohn's disease and this influenced therapeutic strategy in 61% of the patients.

Use of small bowel imaging for the diagnosis and staging of Crohn's disease--a survey of current UK practice

OBJECTIVES

This study used a postal survey to assess the current use of small bowel imaging investigations for Crohn's disease within National Health Service (NHS) radiological practice and to gauge gastroenterological referral patterns.

METHODS

Similar questionnaires were posted to departments of radiology (n = 240) and gastroenterology (n = 254) identified, by the databases of the Royal College of Radiologists and British Society of Gastroenterologists. Questionnaires enquired about the use of small bowel imaging in the assessment of Crohn's disease. In particular, questionnaires described clinical scenarios including first diagnosis, disease staging and assessment of suspected extraluminal complications, obstruction and disease flare. The data were stratified according to patient age.

RESULTS

63 (27%) departments of radiology (20 in teaching hospitals and 43 in district general hospitals (DGHs)) and 73 (29%) departments of gastroenterology replied. These departments were in 119 institutions. Of the 63 departments of radiology, 55 (90%) routinely performed barium follow-though (BaFT), 50 (80%) CT, 29 (46%) small bowel ultrasound (SbUS) and 24 (38%) small bowel MRI. BaFT was the most commonly used investigation across all age groups and indications. SbUS was used mostly for patients younger than 40 years of age with low index of clinical suspicion for Crohn's disease (in 44% of radiology departments (28/63)). MRI was most frequently used in patients under 20 years of age for staging new disease (in 27% of radiology departments (17/63)) or in whom obstruction was suspected (in 29% of radiology departments (18/63)). CT was preferred for suspected extraluminal complications or obstruction (in 73% (46/63) and 46% (29/63) of radiology departments, respectively). Gastroenterological referrals largely concurred with the imaging modalities chosen by radiologists, although gastroenterologists were less likely to request SbUS and MRI.

CONCLUSION

BaFT remains the mainstay investigation for luminal small bowel Crohn's disease, with CT dominating for suspected extraluminal complications. There has been only moderate dissemination of the use of MRI and SbUS.

Ethics and values in prison practice

A small series of pilot seminars on ethics and values in prison practice have been held over the past two years. This article outlines the background, the content and the relevance to prison staff. It concludes that a full trial of the approach for both staff and prisoners would seem to be necessary and that the seminars should be tried with public health practitioners.

Inequalities in colorectal cancer screening participation in the first round of the national screening programme in England

BACKGROUND

Introduction of organised, population-based, colorectal cancer screening in the United Kingdom using the faecal occult blood test (FOBT) has the potential to reduce overall colorectal cancer mortality. However, socio-economic variation in screening participation could exacerbate existing inequalities in mortality.

METHODS

This study examined FOBT uptake rates in London, England in relation to area-level socio-economic deprivation over the first 30 months of the programme during which 401 197 individuals were sent an FOBT kit. Uptake was defined as return of a completed test kit within 3 months. Area-level deprivation in each postcode sector was indexed with the Townsend Material Deprivation Index. Analyses controlled for area-level household mobility, ethnic diversity and poor health, each of which was associated with lower return rates.

RESULTS

The results showed a strong socio-economic gradient in FOBT uptake, which declined from 49% in the least deprived quintile of postcodes to 38% in the middle quintile and 32% in the most deprived quintile. Variation in socio-economic deprivation between sectors accounted for 62% of the variance in return rates, with little attenuation as a result of controlling for ethnic diversity, household mobility or health status.

CONCLUSION

These results highlight the need to understand the causes of socio-economic gradients in screening participation and address barriers that could otherwise increase disparities in colorectal cancer survival.

Rubella seroprevalence among women aged 15-39 years in Morocco

This study was designed to determine the age-specific rubella seroprevalence in women of childbearing age in Morocco and to contribute to the development of a rubella vaccination strategy in the country. Of 967 women aged 15-39 years tested in 2000, 161 (16.6%) were susceptible to rubella based on absence of IgG antibodies. A significantly higher rate of susceptibility among women aged 15-19 years was observed (29.3%) compared with age 35-39 years (8.3%). An estimated 77,562 live births occur annually to rubella-susceptible women. No statistical difference in seroprevalence was seen between women in rural and urban areas (81.5% and 85.0% respectively). A substantial risk of rubella infection exists for Moroccan women of childbearing age.

A rare case of vomiting: fourth ventricular B-cell lymphoma

We document the case of a 69-year-old man presenting with 6 weeks of intractable vomiting. Magnetic Resonance Imaging showed a homogenously enhancing mass in the caudal fourth ventricle. Surgical exploration and biopsy was performed and pathological examination demonstrated a high-grade B-cell lymphoma. The lesion was a primary tumour in an immuno-competent patient. Despite the increasing incidence of primary central nervous system lymphomas this is believed to be only the third ever case to have occurred at this rare site. We suggest that primary B-cell lymphoma should be considered with homogenous lesions of the fourth ventricle.

Modified skin window technique for the extended characterisation of acute inflammation in humans

OBJECTIVE

To modify the skin window technique for extended analysis of acute inflammatory responses in humans, and demonstrate its applicability for investigating disease.

SUBJECTS

15 healthy subjects and 5 Crohn's patients.

TREATMENT

Skin windows, created by dermal abrasion, were overlaid for various durations with filter papers saturated in saline, 100 ng/ml muramyl dipeptide (MDP) or 10 microg/ml interleukin-8 (IL-8).

METHODS

Exuded leukocytes were analyzed by microscopy, immunoblot, DNA-bound transcription factor arrays and RT-PCR. Inflammatory mediators were quantified by ELISA.

RESULTS

Infiltrating leukocytes were predominantly neutrophils. Numerous secreted mediators were detectable. MDP and IL-8 enhanced responses. Many signalling proteins were phosphorylated with differential patterns in Crohn's patients, notably PKC alpha/beta hyperphosphorylation (11.3 +/- 3.1 vs 1.2 +/- 0.9 units, P < 0.02). Activities of 44 transcription factors were detectable, and sufficient RNA isolated for expression analysis of over 400 genes.

CONCLUSIONS

The modifications enable broad characterisation of inflammatory responses and administration of exogenous immunomodulators.

Nanometer-scale ablation with a table-top soft x-ray laser

Ablation of holes with diameters as small as 82 nm and very clean walls was obtained in poly(methyl methacrylate) focusing pulses from a Ne-like Ar 46.9 nm compact capillary-discharge laser with a freestanding Fresnel zone plate diffracting into third order. These results demonstrate the feasibility of using focused soft x-ray laser beams for the direct nanoscale patterning of materials and the development of new nanoprobes.

Analysis of the DNA sequence and duplication history of human chromosome 15

Here we present a finished sequence of human chromosome 15, together with a high-quality gene catalogue. As chromosome 15 is one of seven human chromosomes with a high rate of segmental duplication, we have carried out a detailed analysis of the duplication structure of the chromosome. Segmental duplications in chromosome 15 are largely clustered in two regions, on proximal and distal 15q; the proximal region is notable because recombination among the segmental duplications can result in deletions causing Prader-Willi and Angelman syndromes. Sequence analysis shows that the proximal and distal regions of 15q share extensive ancient similarity. Using a simple approach, we have been able to reconstruct many of the events by which the current duplication structure arose. We find that most of the intrachromosomal duplications seem to share a common ancestry. Finally, we demonstrate that some remaining gaps in the genome sequence are probably due to structural polymorphisms between haplotypes; this may explain a significant fraction of the gaps remaining in the human genome.

Unusual gene order and organization of the sea urchin hox cluster

While the highly consistent gene order and axial colinear patterns of expression seem to be a feature of vertebrate hox gene clusters, this pattern may be less well conserved across the rest of the bilaterians. We report the first deuterostome instance of an intact hox cluster with a unique gene order where the paralog groups are not expressed in a sequential manner. The finished sequence from BAC clones from the genome of the sea urchin, Strongylocentrotus purpuratus, reveals a gene order wherein the anterior genes (Hox1, Hox2 and Hox3) lie nearest the posterior genes in the cluster such that the most 3' gene is Hox5. (The gene order is 5'-Hox1, 2, 3, 11/13c, 11/13b, 11/13a, 9/10, 8, 7, 6, 5-3'.) The finished sequence result is corroborated by restriction mapping evidence and BAC-end scaffold analyses. Comparisons with a putative ancestral deuterostome Hox gene cluster suggest that the rearrangements leading to the sea urchin gene order were many and complex.

Interchromosomal segmental duplications explain the unusual structure of PRSS3, the gene for an inhibitor-resistant trypsinogen

Homo sapiens possess several trypsinogen or trypsinogen-like genes of which three (PRSS1, PRSS2, and PRSS3) produce functional trypsins in the digestive tract. PRSS1 and PRSS2 are located on chromosome 7q35, while PRSS3 is found on chromosome 9p13. Here, we report a variation of the theme of new gene creation by duplication: the PRSS3 gene was formed by segmental duplications originating from chromosomes 7q35 and 11q24. As a result, PRSS3 transcripts display two variants of exon 1. The PRSS3 transcript whose gene organization most resembles PRSS1 and PRSS2 encodes a functional protein originally named mesotrypsinogen. The other variant is a fusion transcript, called trypsinogen IV. We show that the first exon of trypsinogen IV is derived from the noncoding first exon of LOC120224, a chromosome 11 gene. LOC120224 codes for a widely conserved transmembrane protein of unknown function. Comparative analyses suggest that these interchromosomal duplications occurred after the divergence of Old World monkeys and hominids. PRSS3 transcripts consist of a mixed population of mRNAs, some expressed in the pancreas and encoding an apparently functional trypsinogen and others of unknown function expressed in brain and a variety of other tissues. Analysis of the selection pressures acting on the trypsinogen gene family shows that, while the apparently functional genes are under mild to strong purifying selection overall, a few residues appear under positive selection. These residues could be involved in interactions with inhibitors.

Low molecular weight heparin (tinzaparin) vs. placebo in the treatment of mild to moderately active ulcerative colitis

BACKGROUND

Heparin has anti-inflammatory and immunomodulatory activity which may be of therapeutic benefit in the treatment of ulcerative colitis.

AIM

To test whether low molecular weight heparin, given subcutaneously, would provide a significant therapeutic response compared with placebo in the treatment of mild to moderate ulcerative colitis.

STUDY DESIGN

A prospective, double-blind, randomized, placebo-controlled, multi-centre trial comparing tinzaparin 175 anti-Xa IU/kg/day (innohep, LEO Pharma) subcutaneously for 14 days followed by tinzaparin 4500 anti-Xa IU/day subcutaneously for 28 days with placebo, administered subcutaneously once daily for up to 42 days. The primary outcome measure was the mean change in colitis activity from baseline to the end of study treatment assessed by the sum of scores of stool frequency, rectal bleeding, sigmoidoscopic appearance and histology. Secondary outcome measures included changes in individual activity indices and laboratory parameters. Patients were assessed at weekly intervals for 6 weeks and within 1 week of completing treatment.

RESULTS

One hundred patients with active ulcerative colitis (up to six bloody stools per day, no fever, no tachycardia or systemic disturbances) were randomized. Forty-eight received tinzaparin and 52 received placebo. The difference in the mean percentage change in colitis activity from baseline to end of treatment (tinzaparin-placebo) was not statistically significant (P = 0.84). There was no difference between tinzaparin and placebo in any secondary outcome measure. One major bleed (rectal), occurred in a patient receiving placebo.

CONCLUSION

This is the largest trial to date of heparin in ulcerative colitis. The results show no benefit of low molecular weight heparin over placebo in mild to moderately active ulcerative colitis.

Polyomavirus small t antigen prevents retinoic acid-induced retinoblastoma protein hypophosphorylation and redirects retinoic acid-induced G0 arrest and differentiation to apoptosis

Polyomavirus small t antigen (ST) impedes late features of retinoic acid (RA)-induced HL-60 myeloid differentiation as well as growth arrest, causing apoptosis instead. HL-60 cells were stably transfected with ST. ST slowed the cell cycle, retarding G2/M in particular. Treated with RA, the ST transfectants continued to proliferate and underwent apoptosis. ST also impeded the normally RA-induced hypophosphorylation of the retinoblastoma tumor suppressor protein consistent with failure of the cells to arrest growth. The RA-treated transfectants expressed CD11b, an early cell surface differentiation marker, but inducible oxidative metabolism, a later and more mature functional differentiation marker, was largely inhibited. Instead, the cells underwent apoptosis. ST affected significant known components of RA signaling that result in G0 growth arrest and differentiation in wild-type HL-60. ST increased the basal amount of activated ERK2, which normally increases when wild-type cells are treated with RA. ST caused increased RARalpha expression, which is normally down regulated in RA-treated wild-type cells. The effects of ST on RA-induced myeloid differentiation did not extend to monocytic differentiation and G0 arrest induced by 1,25-dihydroxy vitamin D3, whose receptor is also a member of the steroid-thyroid hormone superfamily. In this case, ST abolished the usually induced G0 arrest and retarded, but did not block, differentiation without inducing apoptosis, thus uncoupling growth arrest and differentiation. In sum, the data show that ST disrupted the normal RA-induced program of G0 arrest and differentiation, causing the cells to abort differentiation and undergo apoptosis.

Orexin A immunoreactivity and preproorexin mRNA in the brain of Zucker and WKY rats

The primary role of the orexins was originally believed to be appetite regulation, but is now believed to be the regulation of sleep, arousal and locomotor activity. Orexin A immunoreactivity (orexin A-IR) and prepro-orexin mRNA were measured in the CNS of obese and lean Zucker rats. There were no differences in orexin A-IR or prepro-orexin mRNA levels between obese and lean Zucker rats. The orexins are therefore unlikely to be important in this model of obesity. Levels of orexin A-IR and prepro-orexin mRNA were measured in the CNS of Wistar-Kyoto (WKY) rats, which are hypoactive and have abnormal sleep architecture. Compared to Wistar rats, WKY rats had significantly lower orexin A-IR (with differences of up to 100% in some brain regions) and prepro-orexin mRNA levels. These observations suggest that the sleep and activity phenotype of the WKY strain may be related to orexin deficiency and that this strain may be a useful model of partial orexin deficiency.

Identification of DNA variants in the SNAP-25 gene and linkage study of these polymorphisms and attention-deficit hyperactivity disorder

The gene for the synaptic vesicle docking fusion protein, synaptosomal-associated protein of 25 kDa (SNAP-25), has been implicated in the etiology of attention-deficit hyperactivity disorder (ADHD) based on the mouse mutant strain coloboma. This neutron-irradiation induced mouse strain is hemizygous for the deletion of the SNAP-25 gene and displays spontaneous hyperactivity that is responsive to dextroamphetamine. Because of these characteristics, this strain has been suggested to be a mouse model for ADHD. We identified using single stranded conformational polymorphism analysis (SSCP) four DNA sequence variants in the 3' untranslated region of the human SNAP-25 gene. We searched for polymorphisms in the 3' untranslated region because the intron/exon structure of this gene has not yet been determined. We tested for linkage of this gene and ADHD using two of the identified polymorphisms that change a restriction enzyme recognition site. We examined the transmission of the alleles of each of these polymorphisms and the haplotypes of both polymorphisms using the transmission disequilibrium test in a sample of 97 small nuclear families consisting of a proband with ADHD, their parents, and affected siblings. We observed biased transmission of the haplotypes of the alleles of these two polymorphisms. Our findings are suggestive of a role of this gene in ADHD.

Further evidence from haplotype analysis for linkage of the dopamine D4 receptor gene and attention-deficit hyperactivity disorder

Several studies have suggested a possible association of a polymorphism at the dopamine D4 receptor gene and attention-deficit hyperactivity disorder [LaHoste et al., 1996; Rowe et al., 1998; Smalley et al., 1998; Sunohara et al., submitted; Swanson et al., 1998]. The allele reported to be associated with attention-deficit hyperactivity disorder (ADHD) is the allele with seven copies of the 48 bp repeat in the third exon. We extend our study of the dopamine D4 gene and ADHD by testing for linkage using two additional polymorphisms in the dopamine D4 receptor gene and a polymorphism in the closely linked gene, tyrosine hydroxylase. We also searched for two previously reported deletions, a 13 bp and a 21 bp deletion in the first exon. We examined the haplotypes of three polymorphisms of the D4 receptor gene and observed biased transmission of two of these haplotypes. Our findings further support the role of the dopamine D4 gene in ADHD.

Linkage study of two polymorphisms at the dopamine D3 receptor gene and attention-deficit hyperactivity disorder

Data from animal studies suggest that the dopamine D3 receptor gene may have a role in locomotion and behavioral regulation. Therefore, this gene has been suggested as a candidate for attention-deficit hyperactivity disorder (ADHD). The dopamine D3 receptor gene (DRD3) has two common polymorphisms, one in exon I that changes a Serine to Glycine (Ser9Gly) and alters the recognition site for the restriction enzyme MscI [Lannfelt et al., 1992]. The other common polymorphism is located in intron 5 and results in the change of a restriction site for MspI [Griffon et al., 1996]. We investigated the possibility of linkage of the dopamine D3 receptor gene in 100 small, nuclear families consisting of a proband with ADHD, their parents, and affected siblings. We examined the transmission of the alleles of each of these polymorphisms and the haplotypes of both polymorphisms using the transmission disequilibrium test [Spielman et al., 1993]. We did not observe biased transmission of the alleles at either polymorphism or any haplotype. Our findings using this particular sample do not support the role of the dopamine D3 gene in ADHD. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:114-117, 2000.

Diurnal variation in orexin A immunoreactivity and prepro-orexin mRNA in the rat central nervous system

Orexins are a family of neuropeptides originally believed to be important mediators of food intake. The wide distribution of orexins and their receptors, however, has suggested other regulatory functions for these peptides including involvement in sleep and arousal mechanisms. In this study, we have demonstrated diurnal variation in orexin A immunoreactivity in the pons, from where locus coeruleus noradrenergic neurones innervate other brain areas to stimulate arousal, and in the preoptic/anterior hypothalamic region, an area implicated in the regulation of sleep and circadian rhythms. Orexin A immunoreactivity decreased by 50% in the preoptic/anterior hypothalamus from 09:00 to 21:00 h (P < 0.0001), whilst in the pons, it increased by over 30% from 09:00 to 01:00 h (P = 0.02). Prepro-orexin mRNA also displayed diurnal variation. This further suggests that orexins are involved in the regulation of the sleep/wake cycle.

Lipolysis is an important determinant of isoproterenol-induced myocardial necrosis

The cardiotoxic effect of isoproterenol (ISO) is associated with, and possibly due to, calcium overload. Prior work suggests that calcium entry into cardiac myocytes after ISO administration occurs in two phases: an early rapid phase, followed by a slow phase beginning about 1 hour after ISO injection, leading to a peak myocardial calcium level after about 4 hours. We have tested the relationship of these phases to myocardial necrosis (MN) by determining the time after ISO administration at which the commitment to MN occurs. This was done by administration of propranolol at various times before and after ISO. In addition, since ISO induces lipolysis, and lipids can be toxic, experiments were conducted to determine if adrenergically-activated lipolysis could play a significant role in ISO-MN. We found that propranolol protected the myocardium equally well when administered anytime within 2 hours of ISO injection, but had no effect when given 4 hours after ISO. This showed that metabolic events taking place more than two hours after ISO injection are required for ISO-MN. As expected from prior work, there was a small and consistent amount of propranolol-resistant ISO-MN. Lipolysis, assessed by measuring serum glycerol levels, increased to tenfold above base line at one hour after ISO administration and returned to near basal levels at 4 hours. Potentiation of lipolysis by intravenous injections of phospholipase A2 (PLA2) or lipoprotein lipase (LPL) to rats treated with ISO substantially augmented MN. Propranolol completely blocked the increase in necrosis produced by PLA2 when given with ISO. Lipases induced only minimal necrosis in the absence of ISO. Administration of adenosine (an anti-lipolytic agent), oxfenicine (an inhibitor of mitochondrial palmitoyl carnitine transferase), or vitamin C (an anti-oxidant) resulted in a 55-60% reduction in MN. These results suggest that critical necrosis-determining events occur between 2 and 4 hours after ISO administration and imply a relationship between ISO-induced lipolysis, calcium influx, and ISO-MN. We hypothesize that importance of lipolysis as a determinant of ISO-MN is related to the generation of free fatty acids, their oxidized/metabolic products, or direct damage to plasma membrane.

The NPY Y1 receptor antagonist BIBP 3226 blocks NPY induced feeding via a non-specific mechanism

We have previously shown that intracerebroventricular BIBP 3226 inhibits NPY induced feeding in rats. However, this was associated with abnormal behaviour, likely to be due to interaction with Y1 receptors involved in mechanisms other than the control of food intake. In order to minimise such interactions we investigated the effects of paraventricular nucleus (PVN) injections of BIBP 3226 and its inactive enantiomer BIBP 3435. Intra-PVN injection of NPY (0.1-2.5 nmol/animal) increased food intake, with an EC50 of approximately 0.15 nmol/animal. Injections of BIBP 3226 and BIBP 3435 (0.25-25 nmol) reduced NPY-induced food intake in a dose responsive manner, with BIBP 3226 reducing food intake by 95%, and BIBP 3435 by 65% at the highest dose tested. The reversibility of the effect of BIBP 3226 was investigated by measuring the feeding response to NPY (0.5 nmol) in animals 1 week after BIBP 3226 injection. The response to NPY was less in animals which had received high doses of BIBP 3226. Animals previously injected with saline vehicle alone showed a normal NPY feeding response. These results suggest that BIBP 3226 may be inhibiting NPY-induced food intake in a non-specific manner, not secondary to inhibition of the Y1 receptor. This does not, however rule out a role for the Y1 receptor in the control of food intake by NPY.

Hyperleptinemia as a component of a metabolic syndrome of cardiovascular risk

In humans, production of the adipocyte-derived peptide leptin has been linked to adiposity, insulin, and insulin sensitivity. We therefore considered that alterations in plasma leptin concentrations could constitute an additional component of a metabolic syndrome of cardiovascular risk. To explore this hypothesis, we employed factor analysis, a multivariate statistical technique that allows reduction of large numbers of highly intercorrelated variables to composite, biologically meaningful factors. Seventy-four men [age, 48.4+/-1.3 years (mean+/-SEM); body mass index (BMI), 25.6+/-0.3 kg/m2] who were free of coronary heart disease and diabetes underwent anthropometric measurements (subscapular-to-triceps [S:T] and subscapular-to-biceps [S:B] skinfold thickness ratios, measurement of fasting plasma leptin, and an intravenous glucose tolerance test (IVGTT) for assessment of insulin sensitivity. Plasma leptin concentrations were correlated with BMI (r=0.57, P<0.001), S:T (r=0.34, P=0.003), S:B (r=0.37, P<0.001), systolic and diastolic blood pressures (both r=0.24, P=0.044), fasting triglycerides (r=0.31, P=0.007), serum uric acid (r=0.35, P=0.003), fasting glucose (r=0.32, P=0.003) and insulin (r=0.33, P=0.004), and IVGTT insulin (r=0.63, P<0.001). A negative correlation was observed between leptin and insulin sensitivity (r=-0.32, P=0.006). No significant correlations emerged between plasma leptin concentrations and age, high density lipoprotein cholesterol, or IVGTT glucose. In multivariate regression analyses, BMI (standardized coefficient [SC]=0.40, P=0.001), fasting insulin (SC=0.23, P=0.036), and IVGTT insulin (SC=0.51, P<0.001) emerged as independent predictors of plasma leptin concentrations (R2=0.56, P<0.001). After adjustment for BMI, only IVGTT insulin emerged as a significant predictor of plasma leptin concentrations (SC=0.56, P<0.001, R2=0.45, P<0.001). Factor analysis of plasma leptin concentrations and the variables that are considered relevant to the insulin resistance syndrome revealed a clustering of plasma leptin concentrations with a factor dominated by insulin resistance and high IVGTT insulin, separate from a high IVGTT glucose/central obesity factor and a high triglyceride/low high density lipoprotein cholesterol factor. Together, these factors accounted for 55.9% of the total variance in the dataset. In conclusion, interindividual variations in plasma leptin concentrations are strongly related to the principal components of the insulin resistance syndrome. Further studies are needed to determine whether the insulin-leptin axis plays a coordinating role in this syndrome and whether plasma leptin concentrations could provide an additional measure of cardiovascular risk.

Human mucosal addressin cell adhesion molecule-1 is preferentially expressed in intestinal tract and associated lymphoid tissue

Lymphocyte homing to normal tissues and recruitment to inflammatory tissue sites are controlled, in part, by the selective expression of chemokines, pro-inflammatory cytokines and mediators, and various adhesion proteins and molecules. In the mouse, mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is selectively expressed on endothelium of high endothelial venules in gut and gut-associated lymphoid tissue. By interaction with its integrin ligand, alpha 4 beta 7, lymphocytes presumed to be involved in mucosal immunity are selectively recruited to these intestinal sites. After generating monoclonal antibodies against a murine cell line expressing recombinant human MAdCAM-1, we qualitatively and semiquantitatively assessed MAdCAM-1 expression in human tissue sections from various normal and inflammatory disorders. We found that human MAdCAM-1, as in the mouse, is expressed in a tissue-selective manner. In normal tissues, MAdCAM-1 is constitutively expressed to endothelium of venules of intestinal lamina propria. Interestingly, using computer-assisted morphometric analysis, the proportion of venular endothelium within lamina propria that expresses MAdCAM-1 is increased, compared with normal tissues, at inflammatory foci associated with ulcerative colitis and Crohn's disease. Moreover, for the most part, MAdCAM-1 is not detected in the majority of normal or inflamed extra-intestinal tissues, including those with mucosal surfaces. These results are consistent with a role, as originally defined in the mouse, for human MAdCAM-1 in the localization of alpha 4 beta 7+ lymphocytes in the gastrointestinal tract and associated lymphoid tissue. As such, the pathway defined by MAdCAM-1/alpha 4 beta 7 may be a relevant tissue-specific therapeutic target for the modulation of inflammatory bowel disease activity.