Selection and evaluation of three interventional procedures for achalasia based on long-term follow-up

AIM: To determine the best method out of the three types of interventional procedure for achalasia based on a long-term follow-up.

METHODS: The study cohort was comprised of 133 patients of achalasia. Among them, 60 patients were treated under fluoroscopy with pneumatic dilation (group A), 8 patients with permanent uncovered or antireflux covered metal stent dilation (group B), and 65 patients with temporary partially covered metal stent dilation (group C).

RESULTS: One hundred and thirty dilations were performed on the 60 patients of group A (mean 2.2 times per case). The mean diameter of the strictured cardia was 3.3 ± 2.1 mm before dilation and 10.6 ± 3.8 mm after dilation. The mean dysphagia score was 2.7 ± 1.4 before dilation and 0.9 ± 0.3 after dilation. Complications in group A were chest pain (n = 30), reflux (n = 16), and bleeding (n = 6). Thirty-six patients (60%) in group A exhibited dysphagia relapse during a 12-month follow-up, and 45 patients (90%) out of 50 exhibited dysphagia relapse during a 36-month follow-up. Five uncovered and 3 antireflux covered expandable metal stents were permanently placed in the 8 patients of group B. The mean diameter of the strictured cardia was 3.4 ± 1.9 mm before dilation and 19.5 ± 1.1 mm after dilation. The mean dysphagia score was 2.6 ± 1.3 before dilation and 0.4 ± 0.1 after dilation. Complications in group B were chest pain (n = 6), reflux (n = 5), bleeding (n = 3), and hyperplasia of granulation tissue (n = 3). Four patients (50%) in group B exhibited dysphagia relapse during a 12-month follow-up, and 2 case (66.7%) out of 3 patients exhibited dysphagia relapse during a 36-month follow-up. Sixty-five partially covered expandable metal stents were temporarily placed in the 65 patients of group C and withdrawn after 3-7 d via gastroscopy. The mean diameter of the strictured cardia was 3.3 ± 2.3 mm before dilation and 18.9 ± 3.5 mm after dilation. The mean dysphagia score was 2.4 ± 1.3 before dilation and 0.5 ± 0.2 after dilation. Complications in group C were chest pain (n = 26), reflux (n = 13), and bleeding (n = 8). 6 patients (9.2%) out of 65 exhibited dysphagia relapse during a 12-month follow-up, and 8 patients (14.5%) out of 55 exhibited dysphagia relapse during a 36-month follow-up. All the stents were inserted and withdrawn successfully. The follow-up in groups A-C lasted 12-96 months.

CONCLUSION: Temporary partially covered metal stent dilation is one of the best methods with interventional procedure for achalasia in terms of long-term follow-up.

Short chain fatty acids stimulate epithelial mucin 2 expression through differential effects on prostaglandin E(1) and E(2) production by intestinal myofibroblasts

BACKGROUND

The mucus layer protects the gastrointestinal mucosa from mechanical, chemical, and microbial challenge. Mucin 2 (MUC-2) is the most prominent mucin secreted by intestinal epithelial cells. There is accumulating evidence that subepithelial myofibroblasts regulate intestinal epithelial cell function and are an important source of prostaglandins (PG). PG enhance mucin secretion and are key players in mucoprotection. The role of bacterial fermentation products in these processes deserves further attention.

AIMS

We therefore determined whether the effect of short chain fatty acids (SCFA) on MUC-2 expression involves intermediate PG production.

METHODS

Both mono- and cocultures of epithelial cells and myofibroblasts were used to study the effects of SCFA on MUC-2 expression and PG synthesis. Cell culture supernatants were used to determine the role of myofibroblast derived prostaglandins in increasing MUC-2 expression in epithelial cells.

RESULTS

Prostaglandin E(1) (PGE(1)) was found to be far more potent than PGE(2) in stimulating MUC-2 expression. SCFA supported a mucoprotective PG profile, reflected by an increased PGE(1)/PGE(2) ratio in myofibroblast supernatants and increased MUC-2 expression in mono- and cocultures. Incubation with indomethacin revealed the latter to be mediated by PG.

CONCLUSIONS

SCFA can differentially regulate PG production, thus stimulating MUC-2 expression in intestinal epithelial cells. This mechanism involving functional interaction between myofibroblasts and epithelial cells may play an important role in the mucoprotective effect of bacterial fermentation products.

The epidemiology of chronic generalized musculoskeletal pain

Chronic widespread musculoskeletal pain has been subjected to several epidemiological studies during the last decade. According to these, approximately 10% of the general population report such complaints, clearly indicating chronic widespread musculoskeletal pain as a major health problem in the Western world. Almost unanimously, all studies found higher rates of such complaints among women compared with men, but the mechanisms responsible for the skewed gender ratio remain unknown.Chronic widespread musculoskeletal pain is the clinical hallmark of fibromyalgia and has been the subject of numerous epidemiological studies. The prevalence of fibromyalgia is reportedly 3-5%, again with a significant female predominance. Although the aetiopathogenesis of both fibromyalgia and chronic widespread musculoskeletal pain without other features of fibromyalgia remains an enigma, there is a body of evidence suggesting psychological and sociocultural factors as important for contracting such pain syndromes.

Unilateral placement of metallic stents for malignant hilar obstruction: a prospective study

BACKGROUND

Palliation of patients with malignant hilar stenoses, especially advanced lesions, by stent insertion poses particular difficulties. This study assessed the efficacy of endoscopically inserted unilateral metallic stents for complex malignant hilar obstruction.

METHODS

A prospective, uncontrolled, single-center study was conducted by using a cohort of 61 patients with malignant hilar obstruction. A single, unilateral metallic stent was inserted across the stricture into the duct that technically was easiest to access. Patients were evaluated 1 month after stent placement and, thereafter, every 3 months.

RESULTS

Successful stent insertion was achieved in 59 of 61 (96.7%) patients. In 3 of 61 (4.9%) cases, stent malfunction occurred. Successful drainage was achieved in 59 of 61 (96.7%) patients and complete resolution of jaundice in 86% of cases. Early complications included cholangitis in 3 of 61 (4.9%) patients and stent occlusion in 2 of 61 (3.2%). Late stent occlusion occurred in 14 of 61 (22.9%) patients, including 10 (16.3%) cases of cholangitis and one of liver abscess. Median stent patency was 169 days. Median patient survival was 140 days.

CONCLUSIONS

Unilateral metallic stent insertion is safe, feasible, and achieves adequate drainage in the great majority of patients with nonresectable hilar cholangiocarcinoma.

Selective MRCP and CT-targeted drainage of malignant hilar biliary obstruction with self-expanding metallic stents

BACKGROUND

Endoscopic management of malignant hilar biliary obstruction is controversial with respect to optimal types of stents and extent of drainage. This study evaluated outcomes of selective MRCP and CT-targeted drainage with self-expanding metallic stents.

METHODS

Consecutive patients undergoing attempted palliative ERCP for malignant hilar biliary obstruction were prospectively followed. Whenever possible, management strategy included evaluation and staging for potential resectability before ERCP, with primary placement of metallic stents at the first ERCP in nonsurgical candidates, and early conversion to a metallic stent when a tumor proved to be unresectable. MRCP and/or CT were used to plan selective guidewire access, opacification, and drainage only of the largest intercommunicating segmental ducts. Unilateral stent placement was intended in all cases except for selected patients with Bismuth II cholangiocarcinoma.

RESULTS

Thirty-five patients were included. Bismuth classification was I, 10; II, 6; III, 8; and IV, 11. Tumor origin was bile duct (17), gallbladder (5), and metastatic (13). Metallic stents were placed in 27 patients as the initial stent, and in 8 after plastic stent placement. Initial stents were placed endoscopically in 33 patients and percutaneously in 2 patients in whom lumenal tumor precluded ERCP. Stent placement was unilateral in 31 patients and bilateral in 4 patients. There were no episodes of cholangitis or other complications within 30 days after any procedures. Initial metallic stents were clinically effective in 27 (77%) of the 35 patients. Additional percutaneous drainage in 3 patients who did not respond to initial stent placement did not resolve jaundice. Median patency of first metallic stents was 8.9 months for patients with primary bile duct tumors and 5.4 months for all patients, and was not related to Bismuth classification. No further intervention was needed in 25 (71%) patients.

CONCLUSIONS

Unilateral metallic stent placement by using MRCP and/or CT to selectively target drainage provides safe and effective palliation in most patients with malignant hilar biliary obstruction.

Endoscopic Therapy for Inflammatory Bowel Disease

Endoscopic therapy can be employed and may be useful in inflammatory bowel disease patients with dysplastic polyps, inflammatory strictures (enteric and biliary), bleeding, and for treatment of some complications of continent ileostomies. Dysplastic polyps can be removed endoscopically safely and effectively without resorting to colectomy, as long as there is no other detectable dysplasia in flat mucosa and complete removal can be assured (by biopsy of adjacent mucosa and close follow-up). Some colonic strictures in Crohn's disease can be dilated using endoscopes of graded caliber or with through-the-scope balloons, with or without stent placement. Endoscopy is most useful in dilating anastomotic strictures and less useful for long strictures in active inflammatory disease. Strictures in ulcerative colitis are suspicious for neoplasia and, if dilated at all, should be biopsied extensively and followed closely. We prefer colectomy to endoscopic dilatation for strictures in ulcerative colitis. Biliary endoscopy can be used to dilate strictures in primary sclerosing cholangitis and to sample these areas for malignancy. Although dilatation may improve morbidity and prolong survival, it may not prevent progression to cirrhosis. In cholangiocarcinomas, endoscopic dilatation with or without stents can offer palliation and perhaps be used to deliver photodynamic therapy. Injection and sclerotherapy can be employed in Crohn's disease bleeding from a discrete site. In obstructed continent ileostomies (both Kock pouches and pelvic ileoanal reservoirs), endoscopy can be employed effectively to both determine the cause of the obstruction and re-establish patency. We do not advocate endoscopic treatment of toxic megacolon because of the heightened risk of perforation. Endoscopic therapy of Crohn's fistulas is a possible emerging technology, but it has not been used in large cohorts of patients.

New approach to malignant strictures of the esophagus

Primary esophageal cancer is the most common cause of malignant esophageal stricture. Prognosis and treatment outcomes vary with the stage of the disease. Endoscopic ultrasound has a high accuracy rate for local and regional staging. Surgery is curative for early cancer. Endoscopic mucosal resection, photodynamic therapy, or brachytherapy can be used with curative intent for early cancer, especially in patients with comorbid conditions precluding surgery. Unfortunately, the majority of patients with esophageal cancer present with advanced disease. The primary aim in these patients is to alleviate symptoms with a minimum of side effects and reinterventions. Palliative surgery or chemoradiotherapy can be associated with high morbidity and mortality rates. Several endoscopic techniques for palliation are available, and all have the potential of significantly improving swallowing. The choice of a particular endoscopic approach is usually determined by local expertise and characteristics of the stricture.

Sleep disturbances linked to fibromyalgia

Fibromyalgia (FM) is a chronic muscle disorder characterized by muscle aches and pain of varying intensities. Sleep disturbances have been recognized as one of the probable causes of this disorder. Pharmacological and nonpharmacological approaches are often used to manage the symptoms of sleep disturbances. This article provides a brief background on FM, discusses the physiology of sleep, reviews the current literature on sleep disturbances associated with FM, provides insight to interventions that might be beneficial given the data available, and recommends ongoing research.

Reflux oesophagitis in adult coeliac disease: beneficial effect of a gluten free diet

BACKGROUND

Coeliac disease patients show a number of gastrointestinal motor abnormalities, including a decrease in lower oesophageal sphincter pressure. The prevalence of endoscopic oesophagitis in these subjects however is unknown.

AIM

To evaluate whether untreated adult coeliac patients had an increased prevalence of reflux oesophagitis and, if so, to assess whether a gluten free diet exerted any beneficial effect on gastro-oesophageal reflux disease (GORD) symptoms.

PATIENTS AND METHODS

We retrospectively studied 205 coeliac patients (females/males 153/52, median age 32 years) who underwent endoscopy for duodenal biopsy and 400 non-coeliac subjects (females/males 244/156, median age 37 years) referred for endoscopy for upper gastrointestinal symptoms. Each patient was given a questionnaire for evaluation of GORD symptoms prior to and 4-12 months after endoscopy. Coeliac patients were given a gluten free diet. Oesophagitis patients of both groups, following an eight week course of omeprazole, were re-evaluated for GORD symptoms at four month intervals up to one year. Significance of differences was assessed by Fisher's exact test.

RESULTS

Oesophagitis was present in 39/205 (19%, 95% confidence interval (CI) 13.8-25.0%) coeliac patients and in 32/400 (8%, 95% CI 5.5-11.1%) dyspeptic subjects. At the one year follow up, GORD symptoms relapsed in 10/39 (25.6%, 95% CI 13-42.1%) coeliacs with oesophagitis and in 23/32 (71.8%, 95% CI 53.2-86.2%) non-coeliac subjects with oesophagitis.

CONCLUSION

Coeliac patients have a high prevalence of reflux oesophagitis. That a gluten free diet significantly decreased the relapse rate of GORD symptoms suggests that coeliac disease may represent a risk factor for development of reflux oesophagitis.

Plasma motilin in untreated celiac disease

Celiac disease (CD) is characterized by mucosal villous atrophy mostly confined to the proximal small intestine. Upper-gut motor abnormalities have been reported. Motilin, localized in cells in the proximal small intestine, is a trigger factor for the migrating motor complex. Plasma levels of motilin were studied in 16 untreated CD patients and in an age-matched control group of 18 healthy subjects by radioimmunoassay and by high-performance liquid chromatography (HPLC). The fasting levels of motilin and postprandial levels were significantly higher in CD patients compared to controls (P<0.01) and HPLC revealed a divergent individual pattern of the motilin fragments.

Symptoms across the menstrual cycle in women with irritable bowel syndrome

OBJECTIVE

The purpose of this study was to describe the patterns of GI, somatic, and psychological symptoms across the menstrual cycle in women with irritable bowel syndrome, and to determine whether symptoms differed by oral contraceptive use or predominant bowel pattern.

METHODS

A daily diary was used to assess symptoms across one menstrual cycle. Repeated-measures analysis of covariance, controlling for age and body mass index, was used to compare patterns of symptoms across the menstrual cycle by oral contraceptive use and predominant bowel pattern (diarrhea, constipation, alternating). Data from control women are presented for comparison.

RESULTS

For somatic and psychological as well as GI symptoms, women with irritable bowel syndrome had higher symptom severity than did controls. Women with irritable bowel syndrome using oral contraceptives had lower cognitive, anxiety, and depression symptoms (p < 0.05, but not significant after multiple comparison adjustment), but no differences were seen for most symptoms of irritable bowel syndrome. All symptoms except diarrhea were highest in the alternating group and lowest in the diarrhea group, with the constipation group either intermediate or close to the alternating group. This pattern was significant after multiple comparisons adjustment for GI symptoms, and trending toward significance (p < 0.05, but not significant after multiple comparison adjustment) for menstrual, sleep, and cognitive symptoms. The strongest menstrual cycle effect was seen in somatic and menstrual symptoms. The pattern of symptoms over the menstrual cycle did not differ by predominant bowel pattern or by oral contraceptive use.

CONCLUSIONS

Many of the symptoms examined differed by predominant bowel pattern and menstrual cycle phase, not just the GI symptoms. The menstrual cycle variation was similar regardless of oral contraceptive use or predominant bowel pattern.

Anti-cancer effects of butyrate: use of micro-array technology to investigate mechanisms

Epidemiological evidence suggests that a high intake of resistant starch and NSP protects against colo-rectal cancer. The mechanisms underlying this protection are thought to be mediated by the short-chain fatty acid butyrate, which is present in the colonic lumen in millimolar concentrations as a result of bacterial fermentation of carbohydrates that have resisted digestion in the small intestine. In vitro studies have shown that butyrate displays a host of chemo-preventative properties including increased apoptosis, reduced proliferation, down regulation of angiogenesis, enhanced immunosurveillance and anti-inflammatory effects in colo-rectal cancer cell lines. However, the molecular mechanisms underlying the apparent chemo-preventative actions of butyrate are largely unknown. The evidence supporting the role of butyrate as an anti-cancer agent is reviewed, with particular emphasis on those studies that have attempted to elucidate the mechanism of action of butyrate. Our understanding of the mechanistic action of butyrate and its role in cancer prevention is likely to advance considerably in this post-genomic era with the application of genomic and proteomic technologies. Studies are described that have used gene array and proteomic techniques to investigate the response of colo-rectal cancer cells to butyrate. These pioneering studies illustrate the potential of these technologies to help characterise the molecular responses of the cancer cell to butyrate, and to define the role of butyrate (and other nutrients) in the prevention of colo-rectal cancer.

Balloon dilation and stent placement for esophageal lesions: indications, methods, and results

Esophageal balloon dilation and expandable stent placement are safe, minimally invasive, effective treatments for esophageal strictures and fistulas. These procedures have brought the management of dysphagia due to esophageal strictures into the field of interventional radiology. Esophageal dilation is usually indicated for benign stenoses and is technically successful in more than 90% of cases. Most patients with esophageal carcinoma are not candidates for resection; thus, the main focus of treatment is palliation of malignant dysphagia and esophagorespiratory fistulas. Esophageal stent placement, which is approved only for malignant strictures, is one of the main therapeutic options in affected patients and relieves dysphagia in approximately 90% of cases. Dedicated commercially available devices continue to evolve, each with its own advantages and limitations. Stent placement is subject to technical pitfalls, and adverse events occur following esophageal procedures in a minority of cases. Although chest pain is common and self-limited, reflux esophagitis, stent migration, tracheal compression, and esophageal perforation and obstruction require specific interventions. In many cases, these complications can be recognized and treated by the interventional radiologist with minimally invasive techniques.

Autonomic functioning during REM sleep differentiates IBS symptom subgroups

OBJECTIVE

The aim of this study was to investigate autonomic activity by means of heart rate variability analysis in a sample of irritable bowel syndrome (IBS) patients, allowing stratification into IBS symptom subgroups.

METHODS

Thirty-three female IBS patients (mean age 37 yr) and 21 healthy female controls (mean age 38 yr) participated. Patients were stratified into 16 subjects with only lower bowel symptoms (IBS only) and 17 subjects with both lower bowel and dyspeptic symptoms (IBS+D). The protocol included standard polysomnography to assess stages of sleep with concomitant electrocardiographic measurement of beat-to-beat intervals of the cardiac cycle. Fifteen-min segments were selected from presleep waking, stage 2 of non-rapid eye movement (REM), and REM sleep and analyzed by spectral analysis of heart rate variability to calculate the high-frequency band, a measure of vagal tone, and the low-frequency/high-frequency ratio, an indicator of sympathovagal balance.

RESULTS

The high-frequency band power during REM sleep was significantly lower, indicating substantial vagal withdrawal in IBS-only patients compared with IBS+D patients and controls. The low-frequency/high-frequency band ratio was significantly higher during REM sleep for IBS-only patients.

CONCLUSIONS

IBS-only patients had greater sympathetic dominance, indicated by elevated low-frequency/high-frequency band ratio, during REM sleep because of vagal withdrawal. Autonomic functioning, unique to REM sleep, differentiates IBS symptom subgroups, suggesting that autonomic functioning during REM sleep may be a useful biological marker to identify IBS patient subgroups.

Changes in comorbidities and improvements in quality of life after LAP-BAND placement

Possibly the most important outcomes of bariatric surgery involve changes in obesity-related illness, quality of life (QOL), and psychologic well-being. Dramatic improvement or resolution of serious medical comorbidity accompanies the weight loss following laparoscopic adjustable gastric banding with the LAP-BAND (INAMED Health, Santa Barbara, CA). There are major improvements in the conditions of the metabolic syndrome, which is characterized by impaired glucose tolerance, dyslipidemia, and hypertension. Improvement in insulin sensitivity and pancreatic beta-cell function associated with weight loss induces remission in the majority of type 2 diabetics and reduces the risk of others developing type 2 diabetes. Improvement in dyslipidemia is characterized by raised high-density lipoprotein cholesterol and lower triglyceride concentrations. Together with lower blood pressure, these changes provide a substantial reduction in cardiovascular risk. Other medical conditions caused or aggravated by obesity are also significantly improved, including sleep apnea, daytime sleepiness, asthma, and gastroesophageal reflux. Weight loss is associated with improved fertility and more favorable pregnancy outcomes. All aspects of QOL improve substantially, especially physical disability, and post-weight-loss QOL measures approximate those of the general population. There are also major improvements in body image and reduction in depressive illness. These changes provide perhaps the most compelling data regarding the value of LAP-BAND surgery and underlie the great satisfaction experienced by patients.

Efeito do fator XIII da coagulação na cicatrização da pele de ratos em uso de corticosteróide

OBJETIVOS: Observar o efeito do fator XIII da coagulação (Fibrogamin®) na cicatrização de feridas incisas da pele de ratos tratados com corticosteróide. Foi feita a avaliação quanto ao aspecto histopatológico dos tecidos em cicatrização e sua resistência à tensão. MÉTODO: Foram utilizados 40 ratos Wistar, divididos em quatro grupos. No grupo A (n=10), foi administrado corticosteróide. No grupo B (n=10) foi usado corticosteróide e fator XIII. No grupo C (n=10) foi injetado fator XIII e no grupo D (n=10) foi administrado placebo (controle). A resistência à tensão foi medida através de tensiômetro computadorizado e as alterações histopatológicas quantificadas por análise digital. RESULTADOS: Ocorreu uma significativa diminuição da resistência da ferida de pele no grupo A (523,6gf), quando comparado com o controle (1480,4gf). No grupo B (868,8gf) notou-se significativa diferença em relação ao grupo A (p<0,0001). O grupo C não mostrou diferença (p=0,067) em relação ao grupo controle (D), entretanto foram observadas diferenças significativas quando comparados os grupos A e C; A e D (p<0,0001). A análise da densidade do colágeno e de células inflamatórias revelou as mesmas diferenças observadas na resistência à tensão. CONCLUSÕES: Foi observado que a ação do corticosteróide dificultou a cicatrização da pele de ratos e diminuiu a resistência à tensão, ação revertida pelo uso do fator XIII . A utilização do fator XIII sem uso de corticosteróide não demonstrou ação de melhora nos resultados da cicatrização em relação ao controle.

Colonic epithelial atrophy induced by a fibre-free diet in rats is reversed by minimal amounts of luminal butyrate, but only in the short term

BACKGROUND

Luminal butyrate may be trophic to the colonic epithelium, but this effect is poorly characterized. The aim of the present study was to define the dose-response, time-course, site-specificity and the dependence on background diet of the effects of butyrate on epithelial proliferation in normal distal colon, using an in vivo rat model of colonic substrate delivery.

METHODS

Male Sprague-Dawley rats, maintained on a fibre-free diet, had butyrate infused twice daily into the colonic lumen via polyethylene tubes placed at laparotomy. Varying dose levels (0-80 micro mol/d; 4 d), site (caecal vs distal colonic), duration of infusions (1-5 weeks; 80 micro mol/d), or dietary fibre intake were investigated. Epithelial proliferative indices were assessed stathmokinetically.

RESULTS

Four-day infusions of butyrate led to a progressive trophic effect (cells/crypt column increased from 37.9 +/- 1.6 at 0 micro mol/d to 44.7 +/- 1.2 at 80 micro mol/d) on fibre-deprived colonic mucosa, related linearly to the daily butyrate dose (P < 0.001, linear regression). This effect was mediated by increases in the number and proportion of mitoses, related to the square of the butyrate dose (P < 0.001 in each case, polynomial regression). Butyrate (80 micro mol/d) was associated with significantly higher cellularity (59.9 +/- 1.4) and mitotic activity (4.9 +/- 0.6) per crypt column compared to vehicle controls (50.3 +/- 1.6 and 0.9 +/- 0.2, respectively; P < 0.05, t-tests), at 1 and 3 weeks, but not at 5 weeks. Butyrate had similar effects on distal colonic crypt cellularity (62.0 +/- 1.5) when delivered caecally, but in rats fed a fibre-containing diet, colonic crypt cellularity (55.3 +/- 3.2) was similar to baseline (59.6 +/- 1.9).

CONCLUSIONS

Trophic effects of butyrate are concentration-dependent and occur at low doses in the short term, but are not sustained over longer periods. They are seen only in a fibre-deprived state and appear to be independent of the site of administration.

Pulses and carcinogenesis: potential for the prevention of colon, breast and other cancers

Consumption of pulses as components of healthy diets is encouraged because it is believed that this is likely to help in reducing the risk of common non-communicable diseases, including cancers. However, the evidence base for the role of pulses in prevention of cancers is unconvincing because of the difficulties, using conventional epidemiological tools, in ascertaining the quantitative contribution made by pulses to cancer risk. Advances in understanding of the biological basis of cancer and of the mechanisms of action of cancer-preventing compounds offer new insights into the role of food-derived substances and of diet-gene interactions in modulating cancer risk. Pulses contain a rich variety of compounds which, if consumed in sufficient quantities, may help to reduce tumour risk.

Inhibitory reflexive effect of rectal distension on postprandial gastric myoelectrical activity

The aim of the study was to determine the effects of low-volume rectal distension on gastric myoelectrical activity. The study was performed in 14 healthy volunteers in 2 randomized sessions. In the control session, a small balloon was inserted into the rectum 10 cm beyond the anal verge and inflated with 20 ml of air. Gastric myoelectrical activity was recorded for 30 minutes in the fasting state and 30 minutes after a meal; and then the balloon was deflated and removed, and another 30-min recording was followed. The study session was the same except that after the 30-min baseline recording the balloon was inflated to reach a volume with which the subject felt an urgency for defecation. Spectral analyses were performed to compute the dominant frequency, power, and regularity (2-4 cycles/minutes, cpm) of the gastric slow waves and the percentage of gastric dysrhythmia.

RESULTS

1). In comparison with our previously published data, the placement of the rectal balloon with a volume of 20 ml air did not affect the regularity of the slow waves (84.2 +/- 3.6% in fasting, 85.3 +/- 4.3% in fed); In comparison with the control session, the rectal distension inducing an urgency for defecation (average volume of air: 72.5 ml) significantly reduced the regularity of gastric slow waves in the fed state (72.0 +/- 5.7%, P < 0.03 vs baseline; P < 0.02, vs control session) but not in the fasting state (80.1 +/- 4.5%, P = 0.1). This postprandial change was attributed to a significant increase in bradygastria (3.1 +/- 1.0% vs 7.9 +/- 2.6%, P < 0.04) and a marginal increase in tachygastria (7.4 +/- 2.5% vs 15.8 +/- 4.3%, P = 0.06). The normal postprandial increases in the dominant frequency and power of the gastric slow wave were abolished in both sessions. conclusions, rectal distension evoking an urgency for defecation impairs postprandial gastric slow waves with an increase in the percentage of both bradygastria and tachygastria.

Trichostatin A-histone deacetylase inhibitor with clinical therapeutic potential-is also a selective and potent inhibitor of gelatinase A expression

Modulation of histone acetylation is currently being explored as a therapeutic strategy in treatment of cancer. Specifically, inhibition of histone deacetylase by trichostatin A (TSA) has been shown to prevent tumorigenesis and metastasis. In the present paper we demonstrate that increased histone acetylation by TSA-treated 3T3 cells decreases mRNA as well as zymographic activity of gelatinase A, a matrix metalloproteinase, which is itself, implicated in tumorigenesis and metastasis. Furthermore, TSA inhibits cytochalasin D-induced activation of gelatinase A, but TSA does not affect other members of the gelatinase A activation complex, MT1-MMP and TIMP-2. Thus, TSA is a selective and potent inhibitor of expression and activation of gelatinase A. This finding not only strengthens the rationale for continuing to investigate the therapeutic utility of TSA in cancer, but also, provides evidence that TSA inhibition of gelatinase A expression and activation can be used as a biological marker to monitor and determine end-points of clinical trials involving TSA.

In vitro fermentability of differently substituted xylo-oligosaccharides

Xylo-oligosaccharides (XOS) with various substituents were fermented in vitro by fecal inocula (FI) from four human volunteers to study the influence of substitution on the ability and rate of fermentation and on the production of short-chain fatty acids (SCFA) and lactate. By all FI used nonsubstituted XOS (nXOS) and arabino-XOS (AXOS) were fermented more quickly than the more complex structures of acetylated XOS (AcXOS) and XOS containing a 4-O-methylglucuronic acid group (GlcA(me)XOS). In the first stage (0-40 h) of the fermentations of nXOS and AXOS mainly acetate and lactate were formed. The fermentations of AcXOS and GlcA(me)XOS resulted in a lower lactate production, whereas the concentration of propionate and butyrate increased. These results put emphasis on the detailed elucidation of the structural features of nondigestible oligosaccharides in general to understand their fermentation mechanisms more precisely.

The ubiquitous and tissue specific promoters of the human SRC gene are repressed by inhibitors of histone deacetylases

Histone deacetylase inhibitors have generated keen interest as potential chemopreventive and chemotherapeutic agents due to their ability to induce cell cycle arrest, differentiation, and apoptosis in a diverse group of cancer derived cell lines. Activation of the 60 kDa non-receptor tyrosine kinase, c-Src, has been a consistent finding in many tumors and tumor derived cell lines, and has been implicated in these same cellular processes. We have shown that the histone deacetylase inhibitors, sodium butyrate and Trichostatin A, repressed c-Src mRNA and protein expression in a dose-dependent manner in cell lines derived from cancers of the colon, breast and liver. Our group has previously identified two distinct promoters that are responsible for SRC transcription, separated by a distance of approximately 1 kb. Sodium butyrate and Trichostatin A strongly inhibited activity of each of these highly disparate SRC promoters, demonstrating histone deacetylase inhibitors directly repress SRC transcription. This repression did not require protein neosynthesis and was not associated with a decrease in binding of protein factors essential for either promoter's activity. Our finding that sodium butyrate and Trichostatin A inhibit both SRC promoters suggest this oncogene may be a major target of these agents, and may explain in part their anti-cancer activity.

Sensory-motor responses to volume-controlled duodenal distension

Abstract Visceral perception and secondary peristalsis evoked by distension of the duodenum were studied in 10 healthy volunteers. An impedance planimetric probe for cross-sectional area (CSA) measurements inside a balloon and with three pressure channels was used. Balloon distensions were performed in the fed state with or without the administration of the antimuscarinic drug butylscopolamine. A modified questionnaire was used to assess the nonpainful and painful sensations. The total tension (T(total)) and the passive tension (T(passive)) were determined from the distensions without and with the administration of butylscopolamine, respectively. The active tension (T(active)) was T(total) - T(passive). The stepwise balloon distensions induced the first sensation at a volume of 33 +/- 3 mL. After administration of butylscopolamine the first sensation appeared at 42 +/- 1 mL. The perception score (PS) revealed an approximately linear increase as function of volume, CSA, pressure and tension after the first sensation. Butylscopolamine resulted in significant changes in PS score as function of volume, CSA and strain, but not as a function of pressure and tension. The frequency of the secondary peristalsis increased to the highest value (8.2 +/- 0.8 contractions min(-1)) at a volume of 21 mL. Butylscopolamine almost abolished the distension-evoked motility. T(total) and T(passive) increased nonlinearly as a function of volume, whereas T(active) increased up to a distension volume of 33 mL and then decreased at higher volumes. Hence, the conventional length-tension diagrams as known from studies of smooth muscle strips in vitro can be reproduced in the human duodenum in vivo. This new way of studying intestinal sensation and motility may prove to have both basic and clinical importance as both passive tissue structures and the sensorimotor function are tested.

Stimulation of butyrate production by gluconic acid in batch culture of pig cecal digesta and identification of butyrate-producing bacteria

Gluconic acid reaches the large intestine to stimulate lactic acid bacteria. However, the fermentation pattern of gluconic acid has yet to be elucidated. Accordingly, we examined the fermentation properties induced by gluconic acid in the pig cecal digesta in vitro. We also tested sorbitol and glucose, substrates for which the fermentation rate and patterns are known. The gluconic acid-utilizing bacteria were further isolated from pig cecal digesta and identified to examine the effect of gluconic acid on hind gut fermentation. Gluconic acid was fermented more slowly than were the other two substrates. Gluconic acid stimulated butyrate production; the butyrate molar percentage reached 26%, which is considered a high butyrate production. The majority of gluconic acid fermenters were identified as lactic acid bacteria, such as Lactobacillus reuteri and L. mucosae, and acid-utilizing bacteria, such as Megasphaera elsdenii and Mitsuokella multiacida. The gluconic acid fermented by lactic acid bacteria, and the lactate and acetate that were produced were used to form butyrate by acid-utilizing bacteria, such as M. elsdenii. Gluconic acid may be useful as a prebiotic to stimulate butyrate production in the large intestine.

Pancreatic and biliary tract disorders in inflammatory bowel disease

Hepatobiliary disorders occur frequently in patients with IBD, with PSC and cholangiocarcinoma being the most clinically significant for endoscopists. Endoscopic therapy for PSC is effective in improving symptoms, biochemical parameters, and radiographic abnormalities. Endoscopic therapy may also confer survival benefit, but this has yet to be confirmed in randomized, controlled trials. Treatment should be restricted to those individuals with a rapid decline in liver function testing or those with recurrent cholangitis. Cholangiocarcinoma is a serious complication of PSC and carries an extremely poor prognosis. ERCP with brush cytology has a relatively low sensitivity and the diagnosis is usually made after the disease has become metastatic. Malignant biliary obstruction can be palliated by endoscopic stenting. Photodynamic therapy is a promising experimental technique that may confer symptomatic and survival benefit in patients with nonresectable, advanced cholangiocarcinoma. IBD patients also have an elevated risk for developing acute and chronic pancreatitis as well as pancreatic insufficiency. The majority of cases of acute pancreatitis are likely due to medication side effects and local structural complications of IBD. The remainder may possibly represent true extraintestinal manifestations of IBD. Chronic pancreatitis is frequently subclinical, but may be accompanied by clinically relevant exocrine insufficiency. ERCP is the test of choice for the diagnosis of chronic pancreatitis, but the role of endoscopy in the therapeutic management of IBD-associated chronic pancreatitis remains to be defined.

Resveratrol enhances the differentiation induced by butyrate in caco-2 colon cancer cells

Butyrate, a short-chain fatty acid produced in the colon by microbial fermentation of fiber, inhibits growth of colonic carcinoma cells while inducing differentiation. Resveratrol, a plant polyphenol found in red wine and peanuts, has been shown to exert chemopreventive properties on colon cancer cells. The aim of this study was to determine whether resveratrol modulates the effects of butyrate on Caco-2, a colonic adenocarcinoma cell line. The growth inhibitory effect of resveratrol (50 micromol/L) was more powerful than that of butyrate (2 mmol/L). Butyrate did not intensify the inhibition of proliferation exerted by resveratrol. Although the polyphenol enhanced the differentiation-inducing effect of butyrate, it did not elevate alkaline phosphatase activity or E-cadherin protein expression, markers of epithelial differentiation, when applied alone. Butyrate-induced transforming growth factor-beta1 secretion was inhibited by resveratrol. Treatment with the combination of resveratrol and butyrate attenuated levels of p27(Kip1), whereas resveratrol enhanced butyrate's effect on the induction of p21(Waf1/Cip1) expression. These data demonstrate a possible combined chemopreventive effect of two substances naturally occurring in the colonic lumen after ingestion of fibers and resveratrol-containing food.

Endoscopic therapeutic esophageal interventions

In Western countries, many esophageal diseases result from uncontrolled gastroesophageal reflux. Treatments for Barrett esophagus, peptic strictures, and esophageal adenocarcinoma still account for a large portion of the esophageal interventions performed by therapeutic endoscopists. In addition to continued refinements in the treatment of these sequelae, new endoscopic therapies have emerged to treat gastroesophageal reflux disease itself. This article reviews the available literature on new endoscopic antireflux procedures along with other advances that give the endoscopist unprecedented options in the treatment of esophageal diseases.

Sensation and gas dynamics in functional gastrointestinal disorders

Our current knowledge of motor and sensory functions in the human gut is critically reviewed, showing how the two may interact to produce symptoms in patients with functional gastrointestinal disorders. A local stimulus is necessary to activate the pathogenetic symptom generation process, and in many patients abnormal pooling of gas at various or extensive sites in the bowel and focal gut distension may provide the local stimulus, compounded by spatial summation phenomena and conscious visceral hypersensitivity. The interplay of these mechanisms results in the clinical expression of symptoms.

Cost-effectiveness analysis of alternative strategies for palliation of distal biliary obstruction after a failed cannulation attempt

OBJECTIVES

Occasionally alternative techniques such as precut sphincterotomy or percutaneous transhepatic cholangiography (PTC) are required to achieve access to the common bile duct. Tradeoffs exist, however, with respect to their complications and costs. Some experts believe that precut sphincterotomy should not be performed at all. We aimed to compare the cost-effectivenesses of metallic biliary stent placement after an initial failed cannulation attempt at ERCP utilizing precut sphincterotomy and placement utilizing PTC for palliation of jaundice. A cost-effectiveness analysis was performed, as viewed from the societal perspective.

METHODS

A decision analysis model was designed comparing precut sphincterotomy and PTC approaches for placement of a metallic biliary stent for palliation of jaundice in a patient with inoperable malignant distal biliary obstruction in whom an initial attempt at ERCP cannulation had failed. Baseline probabilities, obtained from the published literature, were varied through plausible ranges using sensitivity analysis. Charges were based on Medicare professional plus facility fees or diagnosis-related group rates for out- and inpatients, respectively. The outcome measured was cost per year of life.

RESULTS

Sensitivity analysis showed that precut sphincterotomy with subsequent PTC, if necessary, was the most cost-effective strategy provided the precut complication rate was <51% ($9,033/yr), versus $14,741/yr for PTC.

CONCLUSIONS

Precut sphincterotomy followed by PTC (if necessary) is the most cost-effective strategy for palliative biliary stenting in the setting of malignant distal biliary obstruction after a failed ERCP attempt. The endoscopic approach is best practiced by experienced endoscopists who minimize precut complication rates.

Food and hypersensitivity in functional dyspepsia

It has long been known that stress affects both the stomach and colon, as shown by the very high prevalence of gastrointestinal symptoms among patients with psychiatric illness. The source may be limbic or peripheral, involving encoded memories or physiological changes. It is important to realise that physical symptoms such as those of functional dyspepsia do not only mean that the patient has a stomach disorder which needs to be identified and treated with specific pharmacological remedies, they often represent, in metaphorical and symbolic form, a state of disharmony brought about a specific psychosocial situation. It is only when that situation is understood and acknowledged that the patient can begin to get better.

Esophageal motor disorders

Refinements continue in the measurement, display, and interpretation of pressure events that serve as signatures of esophageal motor disorders, and esophageal manometry retains its position as the diagnostic gold standard. The focus of attention remains with achalasia, not because of pathophysiologic developments or changing prevalence, but in response to the growing interest in minimally invasive surgery and its success. Some controversy remains regarding the role of preoperative motility assessments in patients undergoing antireflux surgery, as peristaltic features do not solely predict outcome. The disconnect between motor dysfunction and symptoms continues to promote careful consideration of sensory dysfunction as a component of esophageal motor disorders.

Hypersensitivity in functional gastrointestinal disorders

Patients with functional gastrointestinal disorders may have visceral sensory dysfunction so that physiological stimuli induce their symptoms. The clinical significance of altered perception-that is, its relation to clinical symptoms-remains unclear. Data indicate that sensory dysfunction is associated with altered reflex activity. Hence evidence of combined sensory-reflex dysfunction as a common pathophysiological mechanism in various functional gastrointestinal disorders would suggest that they are different forms of the same process. Altered reflex activity and altered conscious perception of gastrointestinal stimuli may combine to differing degrees, and their interaction may produce clinical symptoms.

The nature of pain in irritable bowel syndrome

The diagnosis of irritable bowel syndrome (IBS) is arbitrary, being based on criteria defined by consensus rather than specific biologic markers. IBS is merely a consortium of symptoms and as presently defined is no more a disease than dyspnea or fatigue are diseases. In this context, it is therefore not surprising that defining the nature of pain has proven elusive. It is often etiologically assumed that the origins of the pain seen in IBS patients are mechanistically distinct from those of some of the other symptoms of IBS such as diarrhea and constipation. In addition pain is assumed to be part of a continuum ranging from complete absence of any pain to varying degrees of discomfort to severe pain. Both of these assumptions should be challenged: there are no data to support the notion that discomfort and pain experienced in IBS are mediated through different pathways than symptoms such as bloating or that they are not merely the consequence of the physiological perturbations associated with altered bowel function. Similarly one can easily argue that visceral pain may actually be the cause rather than the effect of the altered gut function seen in IBS. Abdominal discomfort could then be the consequence of the latter and be only indirectly related to pain. It is likely that central (such as stress) and peripheral factors (such as intestinal infection) will produce similar symptoms but via markedly different pathways. It may be time to deconstruct IBS as a concept and to approach the clinical picture from a mechanistic rather than a phenomenological perspective, particularly if we are interested in understanding the basis of the symptoms and develop effective therapeutic modalities. Our patients deserve no less.

Gastrointestinal perception: pathophysiological implications

Physiological gut stimuli during the digestive process are not normally perceived. However, gut stimuli activate a variety of afferent pathways and in some circumstances may induce conscious sensations. Experimental evidence gathered during the past decade suggests that patients with functional gut disorders and unexplained abdominal symptoms may have a sensory dysfunction of the gut, so that physiological stimuli would induce symptoms. Assessment of visceral sensitivity is still poorly developed, but in analogy to somatosensory testing, differential stimulation of visceral afferents may be achieved by a combination of stimulation techniques, which may help to characterize sensory dysfunctions. Visceral afferent input is modulated by a series of mechanisms at different levels of the brain gut axis, and conceivably, a dysfunction of these regulatory mechanisms could cause hyperalgesia. The sensory dysfunction in functional patients seems associated to altered reflex activity, and both mechanisms may interact to produce the symptoms. Evidence of a gut sensory-reflex dysfunction as a common pathophysiological mechanism in different functional gastrointestinal disorders, would suggest that they are different forms of the same process, and that the clinical manifestations depend on the specific pathways affected.

Endoscopic management of biliary disease

Therapeutic biliary endoscopy continues to evolve. Key articles this year primarily involve biliary stenting and biliary stone removal, the two important maneuvers available to the biliary endoscopist. The issues addressed in this review include follow-up after the use of multiple stents for benign strictures, unilateral versus bilateral stenting for Klatskin tumors, stent types and placement positions, the timing and approach to choledocholithiasis in the context of anticipated cholecystectomy, and resistant biliary duct stones.

Cost analysis of magnetic resonance cholangiography in the management of inoperable hilar biliary obstruction

OBJECTIVE

Palliation of patients with Klatskin tumors involving both hepatic ducts is usually performed with bilateral biliary stent placement. Magnetic resonance cholangiopancreatography (MRCP) offers the ability to visualize the hepatic ducts without injection of contrast, thereby reducing the patient's risk of developing postprocedure bacterial cholangitis. We used decision analysis techniques to quantitate the cost-effectiveness of MRCP before stent placement versus routine placement of bilateral biliary stents in the setting of inoperable malignant hilar obstruction. In addition to determining which strategy was most economical, we used sensitivity analysis to identify the critical factors defining relative costs.

METHODS

A decision analysis model was designed comparing MRCP with subsequent unilateral biliary stent placement and double biliary stent placement approaches for palliation of jaundice in a patient with inoperable malignant hilar obstruction, as viewed from the societal perspective. Baseline probabilities, obtained from the published literature, were varied through plausible ranges using sensitivity analysis. Charges were based on Medicare professional plus facility fees or diagnosis-related group rates for out- and inpatients, respectively.

RESULTS

MRCP with subsequent directed unilateral stent placement was the least costly approach ($3806) compared with bilateral stent placement ($4275), provided the bilateral biliary stent complication rate was >3%. Bilateral stent placement needed to confer a survival advantage of at least 7 days over unilateral stent placement to become the more cost-effective approach.

CONCLUSIONS

The use of MRCP to guide biliary stent placement in a patient with inoperable hilar obstruction reduces the overall cost of treatment. The uncertainty of any survival advantage that bilateral biliary stent placement confers over unilateral stent placement makes cost-effectiveness difficult to assess.

Endoscopic markers in adult coeliac disease

BACKGROUND

Various endoscopic markers have been described in coeliac disease, particularly in the second part of the duodenum, with minor attention generally being paid to the duodenal bulb.

AIMS

To evaluate, prospectively, the presence of all endoscopic markers in the bulb and the second part of the duodenum on a large series of patients submitted to endoscopy for duodenal biopsy. PATIENTS AND METHODS. A total of 367 consecutive patients, submitted to endoscopy with duodenal biopsy for various indications, were considered. Biopsies were graded as normal, with partial villous atrophy (mild, moderate, severe) or with subtotal villous atrophy. Endoscopic markers and corresponding locations evaluated were: micronodular pattern [bulb and descending duodenum], mosaic appearance (bulb and descending duodenum), scalloped folds (descending duodenum), reduced or absent folds (descending duodenum).

RESULTS

In 78 patients, a diagnosis of untreated coeliac disease was made. Endoscopic markers were seen in 73/78 patients, with only a single sign present (bulb or descending duodenum) in 12 patients. In the remaining 289 patients, normal histology and normal endoscopic findings were observed, except in two patients with reduced folds. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy regarding all endoscopic markers were 93.6%, 99.3%, 97.3%, 98.3% and 98.1%, respectively

CONCLUSIONS

This study confirms the usefulness of endoscopic markers in detecting coeliac disease, underlining the importance of evaluating also abnormalities in the bulb and endoscopic single signs; although endoscopy may not detect all cases of coeliac disease, the recognition of endoscopic markers allows the selection for biopsy of unsuspected patients submitted to endoscopy for non-specific symptoms.

Modulation of HMG-N2 binding to chromatin by butyrate-induced acetylation in human colon adenocarcinoma cells

Butyrate, a short chain fatty acid (SCFA), is generated by anaerobic fermentation of undigested carbohydrates within the colon. Butyrate enhances acetylation of core histones, a process directly linked to the formation of active chromatin and gene expression. However, additional chromatin components also contribute to the formation of transcriptionally active chromatin. The high mobility group protein N2 (HMG-N2), a nonhistone protein, is involved in chromatin structure modulation. We examined the effects of butyrate on HMG-N2 expression, hyperacetylation and chromatin binding. HT29 human adenocarcinoma cells were incubated with butyrate. Levels of HMG-N2 mRNA and of total or acetylated HMG-N2 protein were analyzed. Protein dynamics were investigated with transfected cells expressing HMG-N2-EGFP fusion proteins. Treatment of HT29 cells with butyrate led to significant hyperacetylation of HMG-N2. Levels of HMG-N2 protein remained unchanged. Northern blot analysis revealed a significant reduction in HMG-N2 mRNA levels after treatment with butyrate. Analysis of HMG-N2-EGFP transfected HT29 cells demonstrated that butyrate treatment changes the binding properties of HMG-N2-EGFP to chromatin. In addition, butyrate treatment resulted in solubilization of endogenous acetylated HMG-N2 into the supernatant of permeabilized cells. We demonstrate that butyrate treatment is associated with hyperacetylation of HMG-N2 protein in HT29 cells. The modulation of this nonhistone chromatin protein resulted in altered binding properties to chromatin. This may represent an additional step in changing chromatin structure and composition with subsequent consequences for transcription and gene expression. Modulation of nonhistone chromatin proteins, like the ubiquitous HMG-N2 proteins, may be partly responsible for the wide range of butyrate-associated effects.

Small bowel review: diseases of the small intestine

In the past year there have been many advances in the area of small bowel physiology and pathology and therapy. In preparation for this review, over 1500 papers were assessed. The focus is on presenting clinically useful information for the practicing gastroenterologist. Selected important clinical learning points include the following: (1) glutamine may restore the AIDs-associated increased intestinal permeability to normal; (2) substance P is a major mediator of diarrhea caused by Costridium difficile toxin A, acting by binding to a G-protein-coupled receptor, and represents a possible 2therapeutic target; (3) the serological diagnosis of celiac disease has been greatly enhanced with the use of anti-endomysial antibody testing, and the recent antitransglutaminase; (4) a quarter of patients with celiac disease may have secondary pancreatic insufficiency and require enzyme replacement therapy; (5) in the patient with unexplained elevation in the serum transaminase concentration, consider celiac disease as an obscure possibility; (6) bosentan and endothelin receptor agonist may prove to be useful in reducing gut ischemia in patients with septic shock; and (7) the administration of recombinant human fibroblast growth factor-2 may prove to be useful to prevent radiation damage to the gastrointestinal tract.

Histone deacetylase as a therapeutic target

The maintenance of health depends on the coordinated and tightly regulated expression of genetic information. Certain forms of leukemia have become paradigms for the pathogenic role of aberrant repression of differentiation genes. In these acute leukemias, fusion proteins generated by chromosomal translocations no longer function as transcriptional activators, but instead repress target genes by recruiting histone deacetylases (HDACs). The potential benefit of HDAC inhibition has been established by the use of enzyme inhibitors in vitro and in a single reported case of experimental therapy. Because recently identified HDAC inhibitors appear to overcome many drawbacks of early inhibitory compounds in clinical use, the stage is set to test the therapeutic value of HDAC inhibition in leukemias and in other diseases, including solid tumors and aberrant hormonal signaling. This review summarizes the range of diseases expected to respond to HDAC inhibition.