Proteinase-activated receptor-4 evoked colorectal analgesia in mice: an endogenously activated feed-back loop in visceral inflammatory pain.

BACKGROUND: Activation of proteinase-activated receptor-4 (PAR-4) from the colonic lumen has an antinociceptive effect to colorectal distension (CRD) in mice in basal conditions. We aimed to determine the functional localization of the responsible receptors and to test their role in two different hyperalgesia models. METHODS: Mice received PAR-4 activating peptide (PAR-4-AP, AYPGKF-NH(2)) or vehicle intraperitoneally (IP), and abdominal EMG response to CRD was measured. The next group received PAR-4-AP intracolonically (IC) with or without 2,4,6-triaminopyrimidine, a chemical tight junction blocker, before CRD. The SCID mice were used to test the role of lymphocytes in the antihyperalgesic effect. The effects of PAR-4-AP and PAR-4-antagonist (P4pal-10) were evaluated in water avoidance stress (WAS) model and low grade 2,4,6-trinitrobenzene sulfonic acid (TNBS) colitis. Spinal Fos protein expression was visualized by immunohistochemistry. KEY RESULTS: The antinociceptive effect of PAR-4-AP disappeared when was administrered IP, or with the blockade of colonic epithelial tight junctions, suggesting that PAR-4-AP needs to reach directly the nerve terminals in the colon. The CRD-induced spinal Fos overexpression was reduced by 43% by PAR-4-AP. The PAR-4-AP was antihyperalgesic in both hyperalgesia models and in mice with impaired lymphocytes. The PAR-4-antagonist significantly increased the TNBS, but not the WAS-induced colonic hyperalgesia. CONCLUSIONS & INFERENCES: The antinociceptive effect of PAR-4-AP depends on its penetration to the colonic mucosa. The PAR-4 activation is endogenously involved as a feedback loop to attenuate inflammatory colonic hyperalgesia to CRD.

Detailed esophageal function and morphological analysis shows high prevalence of gastroesophageal reflux disease and Barrett's esophagus in patients with cervical inlet patch.

Although the pathogenesis of cervical inlet patch (CIP) is not fully understood, most authors consider it as a congenital abnormality, whereas others surmise it to be related to gastroesophageal reflux disease (GERD). We aimed to evaluate esophageal function and the prevalence of GERD and Barrett's esophagus in patients with CIP. GERD is defined by the presence of erosive esophagitis or an abnormal pH monitoring. Seventy-one consecutive patients with endoscopic and histological evidence of CIP were prospectively evaluated. Esophageal symptom analysis, 24-hour simultaneous biliary reflux and double-channel pH-monitoring, and esophageal manometry were carried out in 65/71 (92%) patients and in 25 matched controls. Six patients were not suitable for testing and were, therefore, excluded. The histological evaluation of the heterotopic islands showed cardia and/or oxyntic mucosa in 64/65 (98%) patients and specialized intestinal metaplasia (SIM) in one patient (2%). The cardia and/or oxyntic mucosa was accompanied by focally appearing pancreatic acinar metaplasia and pancreatic ductal metaplasia in 7/64 (11%) and in 1/64 (2%), superficial mucous glands in 6/64 (9%), and SIM in 2/64 (3%) cases. In total, SIM was present in three patients (5%), and one of them had low-grade dysplasia. At the gastroesophageal junction, 28 (43%) patients had columnar metaplasia, including nine (14%) patients with SIM. Erosive esophagitis was present in 37 (57%) cases. Thirty-two patients (49%) had abnormal acid reflux in the distal and 25 (38%) in the proximal esophagus. Abnormal biliary reflux was present in 25 (38%) cases. On the basis of endoscopic and pH studies, GERD was established in 44/65 (68%) patients. Typical reflux symptoms were common (33/65, 51%). The combined 24-hour biliary and double-channel pH-monitoring detected significantly more significant acidic reflux at both measurement points and significantly longer bile exposure time in the distal esophagus in patients with CIP. Acid secretion in the CIP was detected in three (5%) cases. Esophageal manometry revealed decreased LES pressure and prolonged relaxation with decreased peristaltic wave amplitude, and an increased number of simultaneous contractions in the esophageal body. The detailed evaluation of the esophageal morphology and function in subjects with CIP showed a high prevalence of GERD and Barrett's esophagus. Further studies are needed to evaluate whether combined acidic and biliary reflux is able to promote similar histomorphological changes in the CIP, as it is shown distally in patients with Barrett's esophagus.

A renewed insight into Barrett's esophagus: comparative histopathological analysis of esophageal columnar metaplasia.

Specialized intestinal metaplasia (SIM) is considered as a premalignant condition of the esophagus, but other types of esophageal metaplasia are commonly neglected. A standardized histopathological analysis was focused not only on SIM but also on the presence of metaplastic processes typical of additional glands. A morphological study using standardized histopathological tests was carried out between 2004 and 2007, with biopsies taken from esophageal mucosa of 826 consecutive patients. Mean age and male : female ratio of patients were 55.6 ± 14.7 and 1.1 : 1, respectively. Only 4.1% (n = 34) of all cases proved to have SIM. The remainder of the cases (n = 615; 74.4%) contained cardiac-fundic mucosa without SIM. Some samples exhibited superficial mucous glands, pancreatic acinar metaplasia (PAM), and ciliated metaplasia accounting for 24% (n = 198), 14.9% (n = 123), and 0.2% (n = 2), respectively. SIM was colocalized with superficial mucous glands (103/198 superficial mucous gland cases; P < 0.001). Low-grade dysplasia (n = 51; 6.2%) and high-grade dysplasia (n = 9; 1.1%) were found mainly in SIM (37/51; 9/9; P = 0.071) with male preponderance (3 : 1 at low-grade and 2 : 1 at high-grade dysplasia). PAM was found mainly in cases without dysplasia (103 of 123 pancreatic metaplasias; P < 0.001). SIM alone in the esophagus is rare, and its frequent association with cardiac mucosa-type metaplasia testifies to transition of mucinous-goblet cell through pseudogoblet cells. PAM rather indicates absence of dysplasia, but superficial mucous glands predicts that SIM follows dysplasia.

Intracolonic infusion of fecal supernatants from ulcerative colitis patients triggers altered permeability and inflammation in mice: role of cathepsin G and protease-activated receptor-4.

BACKGROUND: Cathepsin G (Cat-G) is a neutrophil serine-protease found in the colonic lumen of ulcerative colitis (UC) patients. Cat-G is able to activate protease-activated receptor-4 (PAR(4) ) located at the apical side of enterocytes, leading to epithelial barrier disruption. However, the mechanisms through which Cat-G triggers inflammation are not fully elucidated. The aims of our study were to evaluate in vivo the effects of UC fecal supernatants and Cat-G on epithelial barrier function and inflammation, and the connection between these two parameters. METHODS: Male balb/c mice were used in this study. We evaluated the effect of a 2-hour intracolonic infusion of 1) fecal supernatants from UC patients pretreated or not with specific Cat-G inhibitor (SCGI); 2) PAR(4) -activating peptide (PAR(4) -AP); and 3) Cat-G on colonic myeloperoxidase (MPO) activity and paracellular permeability (CPP). The involvement of PAR(4) was assessed by pretreating animals with pepducin P4pal-10, which blocks PAR(4) signaling. We investigated the role of myosin light chain (MLC) kinase by using its inhibitor, ML-7, and we determined phosphorylated MLC (pMLC) levels in mice colonic mucosa. RESULTS: UC fecal supernatants, Cat-G, and PAR(4) agonist increased both CPP and MPO activity in comparison with healthy subjects fecal supernatants. ML-7 inhibited the CPP increase triggered by Cat-G by 92.3%, and the enhanced MPO activity by 43.8%. Intracolonic infusion of UC fecal supernatant determined an increased phosphorylation level of MLC. CONCLUSIONS: These observations support that luminal factors such as Cat-G play an important proinflammatory role in the pathogenesis of colitis, mainly depending on CPP increase by MLC phosphorylation.

Increased faecal serine protease activity in diarrhoeic IBS patients: a colonic lumenal factor impairing colonic permeability and sensitivity.

OBJECTIVES: Diarrhoea-predominant irritable bowel syndrome (IBS-D) is characterised by elevated colonic lumenal serine protease activity. The aims of this study were (1) to investigate the origin of this elevated serine protease activity, (2) to evaluate if it may be sufficient to trigger alterations in colonic paracellular permeability (CPP) and sensitivity, and (3) to examine the role of the proteinase-activated receptor-2 (PAR-2) activation and signalling cascade in this process. PATIENTS AND METHODS: Faecal enzymatic activities were assayed in healthy subjects and patients with IBS, ulcerative colitis and acute infectious diarrhoea. Following mucosal exposure to supernatants from control subjects and IBS-D patients, electromyographic response to colorectal balloon distension was recorded in wild-type and PAR-2(-/-) mice, and CPP was evaluated on colonic strips in Ussing chambers. Zonula occludens-1 (ZO-1) and phosphorylated myosin light chain were detected by immunohistochemistry. RESULTS: The threefold increase in faecal serine protease activity seen in IBS-D patients compared with constipation-predominant IBS (IBS-C) or infectious diarrhoea is of neither epithelial nor inflammatory cell origin, nor is it coupled with antiprotease activity of endogenous origin. Mucosal application of faecal supernatants from IBS-D patients in mice evoked allodynia and increased CPP by 92%, both of which effects were prevented by serine protease inhibitors and dependent on PAR-2 expression. In mice, colonic exposure to supernatants from IBS-D patients resulted in a rapid increase in the phosphorylation of myosin light chain and delayed redistribution of ZO-1 in colonocytes. CONCLUSIONS: Elevated colonic lumenal serine protease activity of IBS-D patients evokes a PAR-2-mediated colonic epithelial barrier dysfunction and subsequent allodynia in mice, suggesting a novel organic background in the pathogenesis of IBS.

Colonic luminal proteases activate colonocyte proteinase-activated receptor-2 and regulate paracellular permeability in mice.

Luminal activation of protease-activated receptors-2 (PAR(2)) on colonocytes by trypsin or PAR(2)-activating peptide increases colonic paracellular permeability (CPP). The aim of this study was to evaluate the role of proteases from endogenous and bacterial origin in the modulation of CPP and colonocyte PAR(2) expression in mice. CPP was assessed with (51)Cr-EDTA after intracolonic administration of different protease inhibitors. After 12 days of oral antibiotic treatment, measurements of colonic luminal serine protease activity (CLSPA), CPP, mucosal mouse mast cell proteinase-1 (MMCP-1) content, immunochemistry of PAR(2) and assessment of effects of PAR(2) agonist (SLIGRL) and mast cell degranulator (C48/80) on CPP in Ussing chambers were performed. Immunochemistry was repeated after intracolonic trypsin administration. Colonic infusion of protease inhibitors significantly reduced CPP. In antibiotic-treated mice, CLSPA was reduced coupled with a decrease in PAR(2) expression, but with no change in CPP and MMCP-1 content. Trypsin administration restored PAR(2) expression. The increase in CPP induced by SLIGRL and C48/80 was reduced after antibiotic treatment. Protease activity of colonic content plays an important role in the regulation of mucosal barrier through activation of PAR(2).

Regional differences in the manifestation of gastrointestinal motor disorders in type 1 diabetic patients with autonomic neuropathy.

OBJECTIVE: The aim of this work was to establish the prevalence and severity of different gastrointestinal symptoms and their relationships to esophageal, gastric and recto-anal motor disturbances by manometry in patients with Type 1 diabetes mellitus and autonomic neuropathy. PATIENTS AND METHODS: Sixteen patients (mean age: 53.4 +/- 14.9 years) with long standing type 1 diabetes mellitus (mean diabetes duration: 22.1 +/- 14.7 years) and autonomic neuropathy (mean Ewing score: 5.73 +/- 2.34) were investigated. The gastrointestinal symptom scores were established by using the Talley dyspepsia questionnaire. The motor function of the digestive tract was tested in the esophagus, in the stomach, and in the ano-rectum by perfusion manometry. RESULTS: Manometric evaluation of the esophagus did not reveal significant abnormalities in the region of the upper sphincter in patients with diabetes mellitus. In contrast, diabetic patients had decreased peristaltic wave amplitude, prolonged duration, decreased wave propagation velocity, and increased number of simultaneous contractions in the esophageal body, and decreased lower esophageal sphincter pressures with prolonged relaxation compared to the age- and sex-matched controls. Symptom analysis showed correlations between reflux symptoms and LES relaxation times, and between dysphagia scores and esophageal body peristaltic wave duration, propagation velocity and the rate of simultaneous contractions. In the gastric antrum, frequent, and often severe, fasting motility disorders were observed, which had no correlation with dyspeptic symptoms. In the ano-rectal region the diabetic patients had a lower squeezing-resting pressure difference, and impaired fecal expulsive function. Motility disorders were simultaneously present at multiple parts of the gastrointestinal tract in 13/16 cases. CONCLUSIONS: In patients with type 1 diabetes mellitus and autonomic neuropathy gastrointestinal motility disorders were observed frequently, and in most of the cases simultaneously. While esophageal and ano-rectal symptoms correlated better with the manometric abnormalities, the lack of correlation between the impaired fasting gastric motility and dyspeptic symptoms shows that, on the basis of the clinical symptom analysis, the prevalence of such motor disorders could be underestimated. The early recognition of gastrointestinal motility disorders may be important for the better long-term management of patients with type 1 diabetes mellitus.

Oesophageal acid stimulation in humans: does it alter baroreflex function?

The aim of this study was to investigate if oesophagel acid stimulation (Bernstein test) had an influence on heart rate and blood prsure variability and baroreflex gain. We compared the cardiovascular responses in 10 patients with established gastro-esophageal reflux disease (Group 1) and 10 control subjects (Group 2) during esophageal saline and 0.1 mol/l hydrochloric acid instillation. Indices of heart rate and blood pressure variability and baroreflex gain (derived from linear spontaneous sequences and cross spectral analysis) were calculated. In Group 1 the standard deviation of RR intervals (SDRR: 46 ms vs 51 ms, p=0.030) and the root mean square of successive differences (RMSSD: 24 ms vs. 26 ms p=0.027) were significantly lower during acid infusions, than during saline. We found no significant difference in minimum, maximum and mean RR intervals and systolic blood pressures and in the percentage of RR intervals, which differed from adjacent cycles by more than 50 ms (PNN50). The power spectra of RR intervals in the high frequency band tended to be lower during acid infusion (p=0.055). There was no significant difference in blood pressure spectra, neither in low nor in high frequency band. In Group 2 there was no significant difference between any parameters measured during acid and saline. The baroreflex gain was not changed during the studied conditions in any group. Neither increased vagal tone, nor increased vagal variability occurred and the baroreflex gain was not altered during oesophageal acid simulation.

Impact of weight loss on inflammatory proteins and their association with the insulin resistance syndrome in morbidly obese patients.

OBJECTIVE: Obesity is closely linked to the insulin resistance syndrome (IRS), type 2 diabetes, and cardiovascular disease, the primary cause of morbidity and mortality in these patients. Elevated levels of C-reactive protein (CRP) and interleukin-6 (IL-6), indicating chronic subclinical inflammation, have been associated with features of the IRS and incident cardiovascular disease. METHODS AND RESULTS: We studied the cross-sectional and longitudinal relation of CRP, IL-6, and tumor necrosis factor-alpha (TNF-alpha) with features of the IRS in 37 morbidly obese patients with different stages of glucose tolerance before and 14 months after gastric surgery. Weight loss after gastric surgery induced a significant shift from diabetes (37% vs 3%) to impaired glucose tolerance (40% vs 33%) and normal glucose tolerance (23% vs 64%). The baseline concentration of IL-6 was correlated with TNF-alpha (r=0.59, P<0.01) and CRP (r=0.44, P<0.05) levels. TNF-alpha, IL-6, and CRP were significantly correlated with insulin resistance estimated by the homeostatic model assessment (r=0.48, P<0.05; r=0.56, P<0.01; and r=0.35, P<0.05, respectively). Concentrations of CRP and IL-6 decreased after weight loss (median, 8.6 and interquartile range, 2.7/14.5 vs 2.5 and 1.2/4.1 mg/L; P<0.006, and 5.13 and 2.72/12.15 vs 3.95 and 1.97/5.64 pg/mL, P<0.02, respectively), whereas serum levels of TNF-alpha remained unchanged (8.6 and 6.3/18.8 vs 11.7 and 5.8/17.2 pg/mL; NS.). Multiple regression analysis revealed that the decrease in insulin resistance remained independently and significantly correlated with the decrease in IL-6 concentrations (P<0.01) and the decrease in body mass index with the decrease in CRP (P<0.05), respectively. CONCLUSIONS: Weight loss in morbidly obese patients induces a significant decrease of CRP and IL-6 concentrations in association with an improvement of the IRS.

Significant symptomatic relief after transoral endoscopic staple-assisted treatment of Zenker's diverticulum.

BACKGROUND: Zenker's diverticulum is associated with characteristic symptoms of progressive dysphagia and regurgitation. As most patients are elderly, the perioperative risk is usually high. We report our clinical experience with the transoral endoscopic staple-assisted method, including a thorough assessment of the symptomatic relief achieved by the procedure. METHODS: 46 consecutive patients (29 m, 17 f) with a median age of 61 years (range, 37-96 years) were treated between 1997 and 2002. The symptoms and their frequency were registered. The follow-up consisted of clinical and radiographic investigations. RESULTS: The median size of the diverticulum was 4 cm (range, 2-12 cm). Transoral treatment was successful in 39 patients; in 7 cases (15.2%) a switch to open surgery was required. The median operating time was 30 min (range, 10-150 min). Mortality rate was nil, while morbidity was 7.7%. The median duration of the postoperative hospital stay was 5 days (range, 1-65 days). After a median follow-up of 11 months (range, 1-40 months), 5 patients had been reoperated on endoscopically due to clinical recurrence. Clinical symptoms were significantly reduced (dysphagia of liquids p

Autonomic nervous system dysfunction involving the gastrointestinal and the urinary tracts in primary Sjögren's syndrome.

OBJECTIVE: Antibodies reacting with the m3 subtype muscarinic acetylcholine receptor appear to be an important pathogenic factor in primary Sjögren's syndrome (pSS). As this receptor subtype is functionally important in the gastrointestinal and urinary tracts, and very little is known about the autonomic nervous system function in these organs in pSS patients, the occurrence and clinical significance of an autonomic nervous system dysfunction involving the gastrointestinal and urinary tracts were investigated. METHODS: Data on clinical symptoms attributable to an autonomic dysfunction were collected from 51 pSS patients. Gastric emptying scintigraphy and urodynamic studies were performed on 30 and 16 patients, respectively, and the results were correlated with patient characteristics and with the presence of autonomic nervous system symptoms. RESULTS: Gastric emptying was abnormally slow in 21 of the 30 examined patients (70%). Urodynamic findings, compatible with a decreased detrusor muscle tone or contractility were found in 9 of the 16 patients tested (56%). Various symptoms of an autonomic nervous system dysfunction were reported by 2-16% of the patients. CONCLUSION: Signs of an autonomic nervous system dysfunction involving the gastrointestinal and the urinary systems can be observed in the majority of pSS patients. This high occurrence is rarely associated with clinically significant symptoms. The authors presume a role of autoantibodies reacting with the m3 muscarinic acetylcholine receptor in the elicitation of the autonomic dysfunction.

Continuous enteral feeding has an attenuating effect on the exocrine pancreas in rats.

INTRODUCTION: Recent clinical observations suggest that continuous enteral feeding (CEF) may exert a beneficial effect in the management of inflammatory pancreatic diseases. Its effects on the exocrine pancreas, however, remain only partially investigated. AIM: To examine the effects of CEF on the exocrine pancreas in rats. METHODOLOGY: Eight male Wistar rats were intrajejunally cannulated, and CEF was started on postoperative day 6. In 10 control animals, laparotomy was followed by intragastric feeding (GF) with the same nutriment (Osmolite, Abbott) from postoperative day 6. The daily discharge was 24 kcal in both groups. After 5 days of feeding, the pancreas was removed; its weight and its protein, DNA, trypsin, and lipase contents were determined; and the exocrine pancreas was also examined for structural changes. RESULTS: The results revealed no significant difference in body weight loss between the two groups of animals, whereas the pancreas weight/body weight ratio was lower (p < 0.01) in the CEF group. The pancreatic protein, DNA, and enzyme contents were decreased (p < 0.01) after CEF as compared with the values for the GF group. Histologic examinations demonstrated clear decreases in acinar size and in the zymogen content of the pancreas in the CEF animals. CONCLUSION: This study clearly indicates that CEF reduces the enzyme production of the pancreas.

Video-assisted resection of pulsative midesophagus diverticula.

BACKGROUND: Pulsative diverticula located in the midesophagus occur rarely. Surgical treatment is indicated for symptomatic diverticula. This study evaluated a new minimally invasive method of treatment. METHODS: Three women, ages 69 to 73 years, underwent resections of diverticula via a thoracoscopic access. No major complications were observed. Preoperative symptoms such as dysphagia, regurgitation, aspiration, loss of weight, and retrosternal pain were not reported at follow-up assessment 3 to 60 months after surgery. The patients were highly satisfied with the functional results. CONCLUSIONS: According to our results, minimally invasive treatment of midesophagus diverticula by thoracoscopic resections may be performed with excellent outcome.

[Effect of continuous enteral feeding on pancreas exocrin function in rats]. / Folyamatos enteralis táplálás hatása a hasnyálmirigy exocrin múködésére patkányban.

The aim of this study was to examine the effects of continuous enteral feeding (CEF) on the exocrine pancreas in rats. Eight male Wistar rats were intrajejunally cannulated and CEF was started on postoperative day 6. In 10 control animals, laparotomy was followed by intragastric feeding (GF) with the same nutriment (Osmolite, Abbott, 254 mosm/l) from postoperative day 6. The daily discharge was 24 kcal in both groups. After five days of feeding, the pancreas was removed, its weight and its protein, DNA, trypsin and lipase contents were determined. The results revealed no significant difference in body weight loss between the two groups of animals, whereas the pancreas weight/body weight ratio was lower (p < 0.01) in the CEF group. The pancreatic protein, DNA, trypsin and lipase contents were decreased (p < 0.01) after CEF as compared with the values for the GF group.

[Spontaneous perforation of the large intestine. Resection with primary anastomosis or staged (Hartmann) procedure?]. / Spontane Dickdarmperforation. Resektion mit primärer Anastomose oder Diskontinuitätsresektion (Hartmann)?

Whereas primary resection to remove the septic focus stands undisputed in the therapy of spontaneous perforation of the colon, there is still no consensus as to whether to perform a primary anastomosis or a staged procedure (Hartmann). Prospective randomized studies comparing both concepts are lacking. Obviously these two competing therapies fit different groups of patients whose diseases differ concerning etiology, localisation and severity. Analysis of the literature of the past few years defined some criteria that help to decide when to omit primary anastomosis: MPI > 20, APACHE II score > 15, preoperative organ insufficiency, Hinchey grade III or IV and ASA score IV. In these cases a discontinuity resection is recommended. Primary resection with anastomosis and Hartmann procedure are not competing operations but situation-dependent therapeutic concepts in spontaneous colonic perforation.

[Pedicled flap plasty in closure of defects after recurrence of tumors of the back]. / Gestielte Lappenplastiken zum Verschluss von Defekten nach Tumorrezidiven am Rücken.

Resection of recurrent tumors of the back often results in large transmural defects. Sometimes, radiation therapy is applied after the first operation, leading to indurated, badly vascularized skin and surrounding tissue, often complicated by infection. For this reason, it is necessary to remove not only the tumor but also the surrounding tissue. To reconstruct such wide defects, we use large axial pattern flaps with extension through a fasciocutaneous flap. This leads to safe reconstruction of a complex defect with well-vascularized tissue. We report on two patients with recurrent tumors of the back, reconstructed with combined, extended axial pattern flaps.