[The role of intestinal alkaline phosphatase in pediatric inflammatory bowel and celiac diseases]. / Az intestinalis alkalikus foszfatáz szerepe gyermekkori gyulladásos bélbetegségben és coeliakiában.

Intestinal alkaline phosphatase enzyme plays a pivotal role in the maintenance of intestinal mucosal barrier integrity with the detoxification capacity of lipopolysaccharide, the ligand of Toll-like receptor 4. The inappropriate immune responses and the damage of the mucosal barrier may contribute to the initiation of inflammatory bowel and celiac diseases. In the inflamed colonic mucosa of children with inflammatory bowel disease and in the duodenal mucosa of newly diagnosed children with celiac disease, the decreased intestinal alkaline phosphatase and increased Toll-like receptor 4 protein expression may generate enhanced lipopolysaccharide activity, which may strengthen tissue damaging processes. The enhancement of intestinal alkaline phosphatase activity in an animal model of colitis and in therapy resistant, adult patients with ulcerative colitis reduced the symptoms of intestinal inflammation. In accordance with these results, the targeted intestinal administration of the enzyme in the two examined disorders may be a supplemental therapeutic option in the future.

Preliminary studies of the effects of vascular adhesion protein-1 inhibitors on experimental corneal neovascularization.

Vascular adhesion protein-1 (VAP-1) controls the adhesion of lymphocytes to endothelial cells and is upregulated at sites of inflammation. Moreover, it expresses amine oxidase activity, due to the sequence identity with semicarbazide-sensitive amine oxidase. Recent studies indicate a significant role for VAP-1 in neovascularization, besides its contribution to inflammation. Pathological blood vessel development in severe ocular diseases (such as diabetes, age-related macula degeneration, trauma and infections) might lead to decreased visual acuity and finally to blindness, yet there is no clear consensus as to its appropriate treatment. In the present case study, the effects of two VAP-1 inhibitors on experimentally induced corneal neovascularization in rabbits were compared with the effects of a known inhibitor of angiogenesis, bevacizumab, an anti-vascular endothelial growth factor antibody. In accordance with recent literature data, the results of the preliminary study reported here indicate that the administration of VAP-1 inhibitors is a potentially valuable therapeutic option in the treatment of corneal neovascularization.

Increased expression of serum- and glucocorticoid-regulated kinase-1 in the duodenal mucosa of children with coeliac disease.

OBJECTIVES: Enterocyte apoptosis induced by activated intraepithelial lymphocytes is increased in coeliac disease (CD). Serum- and glucocorticoid-regulated kinase-1 (SGK1) is a serine/threonine protein kinase that may inhibit apoptosis and compensate for the excessive death of surface epithelial cells. The significance of SGK1 in CD is elusive so far. The aim of this study was to characterise the expression and localisation of SGK1 in duodenal biopsy samples taken from children with untreated CD, children with treated CD, and controls. PATIENTS AND METHODS: Duodenal biopsy specimens were collected from 16 children with untreated CD, 9 children with treated CD, and 10 controls. The mRNA expression of SGK1 was determined by real-time reverse transcription-polymerase chain reaction. SGK1 and phosphorylated (P)-SGK1 protein levels and their localisation were determined by Western blot and immunofluorescent staining, respectively. RESULTS: We found increased SGK1-mRNA expression as well as higher SGK1 and P-SGK1 protein levels in the duodenal mucosa of children with untreated CD compared with controls. In the duodenal mucosa of children with treated CD, SGK1-mRNA expression was decreased and SGK1 and P-SGK1 protein levels were lower than in untreated CD. SGK1 and P-SGK1 staining intensity was stronger in duodenal villous enterocytes of children with untreated CD compared with treated CD. CONCLUSIONS: Our results of increased expression of SGK1 in untreated CD may suggest its contribution to the enterocyte survival in this disease.

Claudin-1, -2, -3, -4, -7, -8, and -10 protein expression in biliary tract cancers.

Biliary tract cancers are relatively common malignant gastrointestinal tumors in the elderly. Claudins are integral components of tight junctions that play important roles in maintaining epithelial cell polarity, controlling paracellular diffusion, and regulating cell growth and differentiation. The expression profile of claudins has been extensively characterized, but few reports exist on their expression in the normal and neoplastic biliary tract. Our aim was therefore to study claudins by IHC reactions in normal and neoplastic biliary tract samples. We detected that claudin expressions differ in the normal sample groups: the normal gallbladder strongly expressed claudin-2, -3, -4, and -10, but only weak reactions were seen in normal intrahepatic bile ducts. Although each cancer type expressed several claudins with various intensities, only claudin-4 presented especially strong immunoreactions in extrahepatic bile duct cancers and gallbladder carcinomas, whereas claudin-1 and -10 presented in intrahepatic bile duct cancers. Comparing the normal and carcinoma groups, the most significant decrease was detected in the expression of claudin-10. In conclusion, the expression pattern of claudins is different in the various parts of the normal and neoplastic biliary tract; moreover, an unequivocal decrease was detected in the carcinomas compared with their corresponding normal samples. This manuscript contains online supplemental material at http://www.jhc.org. Please visit this article online to view these materials.

Increased p53 expression in the malignant transformation of Barrett's esophagus is accompanied by an upward shift of the proliferative compartment.

Neoplastic progression in Barrett's esophagus (BE) occurs by a multistep process associated with early molecular and morphological changes. This study evaluated cell proliferation and p53 expression and their correlation in the development and progression of esophageal adenocarcinoma. PCNA and p53 expressions were analyzed in biopsy samples by immunohistochemistry including patients with reflux esophagitis, BE, BE with concomitant esophagitis, Barrett's dysplasia, esophageal adenocarcinoma and a control group without any histological changes. Progressive increase in cell proliferation and p53 expression was found in the sequence of malignant transformation of the esophageal mucosa. While cell proliferation was significantly lower in the control group compared with all other groups, there was no increase in p53 expression of esophageal tissues that were negative for dysplasia. Dysplastic BE tissues revealed significantly higher cell proliferation and p53 expression levels compared to BE, reflux esophagitis or BE with concomitant esophagitis. Both, cell proliferation and p53 expression were significantly higher in adenocarcinoma compared to BE or Barrett's dysplasia. Interestingly, while just BE with concomitant esophagitis showed significantly higher p53 expression levels than BE, both, BE with concomitant esophagitis and reflux esophagitis revealed significantly higher cell proliferation levels compared to BE. Alterations of cell proliferation and p53 expression showed a strong correlation. Simultaneous activation of cell proliferation and p53 expression strongly suggest their association with esophageal epithelial tumor genesis and particularly, their specific role in the biology of esophageal adenocarcinoma. Quantification of these parameters in BE is thought to be useful to identify patients at higher risk for progression to adenocarcinoma.

[Study of claudins and prognostic factors in some gastrointestinal diseases]. / Claudinok és prognosztikai faktorok vizsgálata egyes gastrointestinalis betegségekben.

Gastrointestinal tumors are highly ranked regarding tumoral mortality worldwide. The development and progression of gastrointestinal (GI) diseases go hand in hand with the changes of tight junctions (TJ). Claudins (CLDN) are the main TJ proteins, showing different expression by the different tissues, with the expressed CLDN profile being representative. I. We explored the changes of CLDN expression in Barrett's esophagus and related adenocarcinoma. CLDN2 and -3 expression in Barrett's esophagus was higher than in normal foveolar epithelium. Adenocarcinoma showed higher CLDN2 and -3 expression compared with normal and Barrett's epithelia. The similar CLDN expression profile of Barrett's esophagus and adenocarcinoma supports their sequential development. II. Gastric intestinal metaplasia showed higher expression of CLDN2, -3 and -4 as compared with normal antral foveolar mucosa. Tumors of small and large bowels exhibited higher CLDN2 expression when compared with normal epithelia. Colorectal adenoma and adenocarcinoma could not be differentiated according to their CLDN profile. Intestinal metaplasias of Barrett's esophagus and stomach show similar CLDN profile to small bowel epithelium. III. Studies on duodenal mucosa in celiac disease in childhood demonstrated CLDN2 and -3 expression to be higher than in normal mucosa. The expression was significantly higher in the distal part of the duodenum samples. This and the serious histological findings suggest that the distal duodenum is more adequate for biopsy testing. IV. Beside the epithelial cells, mesenchymal tumors express intercellular junctional proteins. Expression of claudins in gastrointestinal stromal tumors (GIST) and other mesenchymal neoplasia was also studied. The CLDN profile was found to be representative to the individual tumor. GIST, angiosarcoma, hemangioma, leiomyosarcoma and leiomyoma showed expression of various CLDNs. CLDN2 was detected in all entities. CLDN1, however, was found positive in leiomyosarcoma only. Leiomyoma, on the other hand, expressed only CLDN2. GISTs and leiomyosarcomas showed CLDN2, -3, -4, -5 and -7-expression. The angiogenic tumors revealed CLDN2 and -5 expression. The similar CLDN profile observable in GIST and leiomyosarcoma is suggestive of a histogenetic relationship. Smooth muscle and vessel tumors of different dignity could also be separated from each other based on CLDN profile.

[Crohn's disease of the duodenum. Clinical signs, diagnosis, conservative and surgical treatment]. / A duodenum Crohn-betegsége, klinikai jelek, diagnosztika, gyógyszeres és sebészi kezelés.

UNLABELLED: Duodenal localization of Crohn's disease is rare, accounting for only 0.5-4% of all cases. Most common complaints are gastric outlet obstruction and weight loss. Histologic findings of endoscopic biopsy are frequently not definitive, making differentiation from other, benign structures complicated. There are also no standard guidelines regarding indications for surgical management. PATIENTS AND METHODS: We reviewed the cases of three surgically managed patients with duodenal Crohn's disease at the 1st Department of Surgery, Semmelweis University of Medicine, Budapest, during a 5-year period (2002-2007). All three patients had persistent symptoms of stomach emptying disorder despite medical therapy and had severe weight loss (13-30 kg). In two cases resection of the stenotic duodenum was performed successfully using Billroth II method. Gastro-jejunal bypass was performed in one case, where the descendent duodenum was inflamed. RESULTS: All patients have been asymptomatic since surgery (9-45 months of follow-up) and recovered their earlier bodyweight. The postoperative period was uneventful. CONCLUSIONS: There is indication of surgery in cases of stenosing duodenal Crohn's disease, when medical therapy is not successful, but long-standing malnutrition should be treated preoperatively. We found perioperative morbidity to be similar in patients with duodenal Crohn's and in those with Crohn's disease of other intestinal locations.

Extra-pulmonary primary small-cell neuroendocrine carcinoma arising from the duodenum: rare tumor, unusual location.

Small-cell neuroendocrine carcinoma is a high-grade carcinoma rarely encountered in extra-pulmonary sites. A 40-year-old lady presented with epigastric pain and was noted to have an ulcerated small-cell neuroendocrine carcinoma in her duodenum with liver metastases. She underwent palliative chemotherapy but unfortunately passed away. Duodenal SCNC is an unusual malignancy with an aggressive phenotype.

Claudin expression in Barrett's esophagus and adenocarcinoma.

Claudins (CLDNs) are key molecules in cell adhesion, polarity, and control of paracellular solute transport. Several studies suggested that changes in claudin pattern have a role in cancer development. This study aimed to detect alterations in CLDN 1, 2, 3, 4, and 7 expression patterns in Barrett's esophagus (BE) and adenocarcinoma (ACC) compared with that in foveolar epithelium (FOV), normal squamous epithelium (SQ), and squamous cell carcinoma (SQCC). One hundred twenty five surgically or endoscopically removed, paraffin-embedded cases were studied by immunohistochemistry and analyzed statistically. BE, ACC, and FOV were dissected from 30 paraffin-embedded samples for further mRNA expression analysis. CLDN 7 was the dominating type in all epithelia and carcinomas, but its expression did not differ in normal and altered tissues. CLDN 1 expression was significantly increased in SQCC compared with that in SQ. CLDNs 3 and 4 were significantly elevated both in BE and ACC compared with that in FOV. CLDN 2 expression increased significantly in ACCs compared with that in BE. This is the first report proving similarities and differences regarding claudin expression pattern in BE and ACC compared with that in FOV and SQ. Our data prove a close link in CLDN pattern between BE and ACC, adding further evidence that BE is an alteration preceding esophageal ACC.

[Pancreas pseudocyst or metastasis?]. / Pancreas-pseudocysta vagy metasztázis?

The authors review a case of a 24-year-old male patient hospitalised for repeated acute abdominal symptoms. His medical history included no diseases worth of mentioning. By imaging techniques (abdominal US and CT scan) a cystic lesion, measuring 40 x 35 x 30 mm in diameter was found, and was diagnosed as pseudocyst in the region of the tail of the pancreas. Jejunal feeding was introduced. The lesion did not improve and the second CT scan suggested a suspicion of pancreatic cystadenoma. Three months after first presentation the surgical resection was performed. The tumour, however, was found independent of the pancreas (90 x 80 x 50 mm). Both histologically and immunohistochemically the lesion proved to be the metastasis of a germ cell (yolk-sac) tumour. Following the morphological diagnosis, detailed urological and medical check up was performed. A previously nonpalpable small tumour was found in the left testis which was radically resected. The testicular tumour measuring 9 x 9 x 5 mm in diameter was diagnosed as embryonal carcinoma. Later on the patient underwent chemotherapy. He has been undergoing close oncological followup. Clinically, he is disease free. Authors emphasize the importance of imaging techniques and fine needle aspiration cytology in the case of retroperitoneal masses in young males. The possibility of a metastasis, especially of germ cell origin, should be excluded (not only by physical examination, but by ultrasound of testis also) in case of retroperitoneal cystic tumours even with unusual morphology.

Gastrointestinal stromal tumors, intramural leiomyomas, and leiomyosarcomas in the duodenum: a clinicopathologic, immunohistochemical, and molecular genetic study of 167 cases.

In this study we analyzed the clinicopathologic features of duodenal smooth muscle or stromal tumors, including 156 GISTs, 6 leiomyomas (LMs), and 5 leiomyosarcomas (LMSs) from the files of the Armed Forces Institute of Pathology and the Haartman Institute of the University of Helsinki. GISTs were documented as KIT positive (n = 109); 47 tumors were also included because of their histologic identity to KIT-positive cases. GIST-specific c-kit gene mutations were documented in exon 11 in 9 of 30 cases (30%) and exon 9 in 4 of 30 cases (13%). The GISTs occurred in patients with an age range of 10-88 years (median 56 years); 54% were male. Ten patients had neurofibromatosis type I; six of them had multiple GISTs. The GISTs ranged from small asymptomatic intramural or external nodules to large masses that extended into the retroperitoneum (median size 4.5 cm). They were mostly spindle cell tumors; three malignant GISTs had an epithelioid morphology, and 81 cases had skeinoid fibers. The tumors often coexpressed CD34 and KIT (54%) and were variably positive for smooth muscle actin (39%) and S-100 protein (20%) but never for desmin. A total of 86% of patients with tumors >5 cm with >5 mitoses/50 high power fields (HPF) (n = 21) died of disease, whereas no tumor <2 cm with <5 mitoses/50 HPF (n = 12) recurred or caused death. Long latency was common between primary operation and recurrences or metastases; either one occurred in 49 of 140 patients with follow-up (35%). No formula could accurately predict metastases, which occasionally developed even if mitotic activity was <5/50 HPF and size <5 cm. Metastases were in the abdominal cavity, liver, and rarely in bones and lungs but never in lymph nodes. Four actin- and desmin-positive and KIT-negative benign intramural LMs were similar to those more often seen in the esophagus. There were five LMSs, one of which formed a polypoid intraluminal mass; all were actin positive and KIT negative. The great majority of duodenal mesenchymal tumors are GISTs, which have a spectrum from small indolent tumors to overt sarcomas. LMs and LMSs are rare.

Second-line and third-line trial for helicobacter pylori infection in patients with duodenal ulcers: A prospective, crossover, controlled study.

BACKGROUND: Following standard first-line triple therapies for Helicobacter pylori infection, up to 20% of patients require further eradication. OBJECTIVE: The aim of this study was to assess the effects of second-line triple therapies and third-line quadruple therapies for the eradication of H pylori. METHODS: This 7-week, prospective, crossover, controlled, second- and third-line trial was conducted at the Department of Gastroenterology, Ferencváros Health Center (Budapest, Hungary). Patients aged 18 to 80 years with duodenal ulcers and an H pylori infection resistant to first-line triple therapy (pantoprazole 40 mg BID + amoxicillin 1000 mg BID + clarithromycin 500 mg BID [PAC] given as tablets) received a different triple therapy regimen (ranitidine bismuth citrate 400 mg BID + metronidazole 500 mg BID + clarithromycin 500 mg BID [RBC-MC]) for 7 days (group 1A), and nonresponders after RBC + 2 antimicrobials received the pantoprazole-based regimen (group 1B). After secondary failure, patients were randomized to receive quadruple therapies: pantoprazole, amoxicillin, tetracycline, and either nitrofurantoin or bismuth subsalicylate (groups 2A and 2B). RESULTS: One hundred thirty-four patients were enrolled in the second-line study (56 men, 78 women; mean [SD] age, 51.1 [12.4] years; group 1A, 68 patients; group 1B, 66 patients). Subsequently, 41 (30.6%) of these patients were randomized to receive quadruple therapies. Using intent-to-treat (ITT) analysis, the eradication rates did not differ significantly (60.3% and 65.2% in groups 1A and 1B, respectively; 61.9% and 55.0% in groups 2A and 2B, respectively). Perprotocol eradication rates did not differ significantly (66.1% and 68.3% in groups 1A and 1B, respectively); however, the rates were significantly different in group 2A (66.7%) versus group 2B (55.5%) (P = 0.03).

[Correlation of Barrett's esophagus and colonic adenomas]. / Barrett-nyelócsó és colonadenoma kapcsolata.

INTRODUCTION: According to the case-control studies, colon adenomas are not more frequent as usual in patients with Barrett's oesophagus. AIM: Analysis of the relationship of Barrett's oesophagus with colon adenomas through a case presentation. METHOD: The 62-years old male patient has been treated with pantoprazole for reflux oesophagitis and histologically proven short-segment Barrett's oesophagus. Pantoprazole treatment was started and the patient became symptom-free. In 1997 colonoscopy was performed for rectal bleeding and 4 recto-sigmoideal polyps were removed (tubular adenomas). After 4 years of PPI treatment, laparoscopic fundoplication was performed but after one year of symptom-free period, PPI was started again because of relapse. The patient was followed-up for 5 years. The histological examinations included also Ki67 and p53 antibody staining. RESULTS: On control colonoscopies, small rectal and sigmoid polyps were found. The retrospective histologic examination of the polyps revealed the increase of Ki-67-positive cells from 2-5% to 45-55% during the 5 years of follow-up, which is higher than the values found in controls and may express the increasing proliferative activity of the epithelium. CONCLUSION: Although according to the literature, Barrett's oesophagus does not increase the risk of colon adenomas, this may occur in individual cases, warranting close follow-up.

Peroxisome proliferator-activated receptor-γ and thymic stromal lymphopoietin are involved in the pathophysiology of childhood coeliac disease.

Celiac disease (CD) is a chronic autoimmune enteropathy caused by exposure to dietary gluten in genetically predisposed individuals. The transcription factor peroxisome proliferator-activated receptor gamma (PPARγ) was shown to exert protective effects in several immune-mediated disorders. Activation of PPARγ suppressed the expression of thymic stromal lymphopoietin (TSLP), an inducer of proinflammatory cytokines. Since the role of TSLP in gluten-sensitive enteropathy is completely unknown, we investigated the involvement of TSLP and its regulator PPARγ in childhood CD. We collected duodenal biopsy specimens from 19 children with newly diagnosed CD, 6 children with treated CD (gluten-free diet, GFD), and 10 controls. Expression of mRNA and protein levels of PPARγ, TSLP, and TSLP receptor were determined by real-time RT-PCR and Western blot, respectively. Duodenal localization of PPARγ and TSLP was studied by immunohistochemistry. In duodenal mucosa of children with CD, the amount of PPARγ was significantly lower and simultaneously that of TSLP significantly higher compared to controls (p < 0.05). In GFD-treated patients, the levels of PPARγ mRNA and protein were significantly higher while that of TSLP markedly lower compared to newly diagnosed CD (p < 0.05). Immunohistochemistry revealed PPARγ and TSLP expression in lamina propria immune cells and in enterocytes. Low expression of PPARγ and high expression of TSLP in the duodenal mucosa of children with newly diagnosed CD suggest that they are involved in the pathophysiology of CD. We hypothesize that PPARγ may be an inhibitory regulator of TSLP-stimulated inflammatory processes in CD.

Characteristics of allergic colitis in breast-fed infants in the absence of cow's milk allergy.

AIM: To investigate the characteristics of mucosal lesions and their relation to laboratory data and long-term follow up in breast-fed infants with allergic colitis. METHODS: In this study 31 breast-fed infants were prospectively evaluated (mean age, 17.4 wk) whose rectal bleeding had not ceased after a maternal elimination diet for cow's milk. Thirty-four age-matched and breast-fed infants (mean age, 16.9 wk) with no rectal bleeding were enrolled for laboratory testing as controls. Laboratory findings, colonoscopic and histological characteristics were prospectively evaluated in infants with rectal bleeding. Long-term follow-up with different nutritional regimes (L-amino-acid based formula or breastfeeding) was also included. RESULTS: Iron deficiency, peripheral eosinophilia and thrombocytosis were significantly higher in patients with allergic colitis in comparison to controls (8.4 ± 3.2 µmol/L vs 13.7 ± 4.7 µmol/L, P < 0.001; 0.67 ± 0.49 G/L vs 0.33 ± 0.17 G/L, P < 0.001; 474 ± 123 G/L vs 376 ± 89 G/L, P < 0.001, respectively). At colonoscopy, lymphonodular hyperplasia or aphthous ulceration were present in 83% of patients. Twenty-two patients were given L-amino acid-based formula and 8 continued the previous feeding. Time to cessation of rectal bleeding was shorter in the special formula feeding group (mean, 1.4 wk; range, 0.5-3 wk) when compared with the breast-feeding group (mean, 5.3 wk; range, 2-9 wk). Nevertheless, none of the patients exhibited rectal bleeding at the 3-mo visit irrespective of the type of feeding. Peripheral eosinophilia and cessation of rectal bleeding after administration of elemental formula correlated with a higher density of mucosal eosinophils. CONCLUSION: Infant hematochezia, after cow's milk allergy exclusion, is generally a benign and probably self-limiting disorder despite marked mucosal abnormality. Formula feeding results in shorter time to cessation of rectal bleeding; however, breast-feeding should not be discouraged in long-lasting hematochezia.

Expression of PARK7 is increased in celiac disease.

Recently, it has been suggested that the gene called Parkinson's disease 7 (PARK7) might be an upstream activator of hypoxia-inducible factor (HIF)-1α, which plays a major role in sustaining intestinal barrier integrity. Furthermore, PARK7 has been proposed to participate in the Toll-like receptor (TLR)-dependent regulation of the innate immune system. Our aim was to investigate the involvement of PARK7 in the pathogenesis of coeliac disease (CD). Duodenal biopsy specimens were collected from 19 children with untreated CD, five children with treated CD (maintained on gluten-free diet), and ten children with histologically normal duodenal biopsies. PARK7 mRNA expression and protein level were determined by real-time polymerase chain reaction (PCR) and Western blot, respectively. Localization of PARK7 was visualized by immunofluorescence staining. Protein level of PARK7 increased in the duodenal mucosa of children with untreated CD compared to children with treated CD or to control biopsies (p <0.03). We detected intensive PARK7 staining in the epithelial cells and lamina propria of the duodenal mucosa of children with untreated CD compared with that in control biopsies. Our finding that mucosal expression of PARK7 is increased suggests that PARK7 is involved in the pathogenesis of gastrointestinal diseases, notably CD. Our results suggest that PARK7 may alter processes mediated by HIF-1α and TLR4, which supports a role for PARK7 in the maintenance of epithelial barrier integrity, immune homeostasis, or apoptosis.

Decreased mucosal expression of intestinal alkaline phosphatase in children with coeliac disease.

A major function of the enzyme intestinal alkaline phosphatase (iAP) is the detoxification of lipopolysaccharide (LPS), the ligand of Toll-like receptor 4 (TLR4). Hence, iAP has a role in the defence of maintaining intestinal barrier integrity. As intestinal barrier integrity is impaired in coeliac disease (CD), we tested the expression and localization of iAP in duodenal mucosa specimens from children with newly diagnosed CD (n = 10), with CD on gluten-free diet (GFD) (n = 5) and compared to those from ten healthy children. The mRNA and protein expression was determined by RT-PCR and Western blot analysis, respectively. Tissue localization of iAP and TLR4 was determined by immunofluorescence staining. iAP protein expression level was significantly lower than normal in newly diagnosed CD, while it was normalised in children on GFD. iAP and TLR4 colocalized at the epithelial surface of duodenal mucosa in each group of subjects enrolled. The finding of decreased iAP protein levels in newly diagnosed CD is consistent with its role in decreased intestinal barrier integrity. The latter may be the result of decreased LPS-detoxifying ability.

Intestinal alkaline phosphatase in the colonic mucosa of children with inflammatory bowel disease.

AIM: To investigate intestinal alkaline phosphatase (iAP) in the intestinal mucosa of children with inflammatory bowel disease (IBD). METHODS: Colonic biopsy samples were taken from 15 newly diagnosed IBD patients and from 10 healthy controls. In IBD patients, specimens were obtained both from inflamed and non-inflamed areas. The iAP mRNA and protein expression was determined by reverse transcription-polymerase chain reaction and Western blotting analysis, respectively. Tissue localization of iAP and Toll-like receptor (TLR) 4 was investigated by immunofluorescent staining. RESULTS: The iAP protein level in the inflamed mucosa of children with Crohn's disease (CD) and ulcerative colitis (UC) was significantly decreased when compared with controls (both P < 0.05). Similarly, we found a significantly decreased level of iAP protein in the inflamed mucosa in CD compared with non-inflamed mucosa in CD (P < 0.05). In addition, the iAP protein level in inflamed colonic mucosa in patients with UC was decreased compared with non-inflamed mucosa in patients with CD (P < 0.05). iAP protein levels in the non-inflamed mucosa of patients with CD were similar to controls. iAP mRNA expression in inflamed colonic mucosa of children with CD and UC was not significantly different from that in non-inflamed colonic mucosa with CD. Expression of iAP mRNA in patients with non-inflamed mucosa and in controls were similar. Co-localization of iAP with TLR4 showed intense staining with a dotted-like pattern. iAP was present in the inflamed and non-inflamed mucosa of patients with CD, UC, and in control biopsy specimens, irrespective of whether it was present in the terminal ileum or in the colon. However, the fluorescent signal of TLR4 was more pronounced in the colon compared with the terminal ileum in all groups studied. CONCLUSION: Lower than normal iAP protein levels in inflamed mucosa of IBD patients may indicate a role for iAP in inflammatory lesions in IBD. Based on our results, administration of exogenous iAP enzyme to patients with the active form of IBD may be a therapeutic option.

Mucosal expression of claudins 2, 3 and 4 in proximal and distal part of duodenum in children with coeliac disease.

Duodenal biopsy is an important tool to diagnose coeliac disease (CD); however, the most reliable location of biopsy site is still questionable. Claudins (CLDNs), members of a large family of adherent junction proteins, show characteristic expression pattern in inflammatory disorders; nevertheless, CLDN expression in CD is unknown. This is a comparative study to examine the CLDN 2, 3 and 4 expressions in proximal and distal part of duodenum in children with CD and in controls. Thirty-three children with newly diagnosed CD were enrolled. Fourteen healthy children served as controls. Biopsies from proximal and distal part of duodenum were taken for routine histological analysis. Immunohistochemistry were used to detect CD3+ intraepithelial lymphocytes and CLDN 2, 3 and 4 protein expressions. Macroscopic picture, routine histology and Marsh grade depicted no differences between biopsies taken from proximal or distal part of duodenum. However, CLDN 2 expression was significantly increased in severe form of coeliac disease in bulb and in distal duodenum, and in distal part of non-severe coeliac patients, in comparison to controls. Similar association was found concerning CLDN 3 expression. Expression of CLDN 4 was similar in all groups studied. Both proximal and distal mucosal duodenal biopsies are suitable for diagnosing villous atrophy in patients with CD. Increased expressions of CLDN 2 and 3 suggest structural changes of tight junction in coeliac disease which may be, at least in part, responsible for increased permeability and proliferation observed in coeliac disease.