Stefania Masone

Mucosal abnormalities of the small bowel in patients with cirrhosis and portal hypertension: a capsule endoscopy study

BACKGROUND The frequency of small-bowel mucosal changes in patients with portal hypertension is not known. The objective of the study is to better define the mucosal abnormalities of portal hypertensive enteropathy (PHE) and to determine whether these findings are associated with the severity of liver disease, esophageal varices, portal gastropathy, portal colonopathy, or other clinical characteristics. METHODS We compared the medical records of 37 patients with cirrhosis and portal hypertension with 34 control patients who underwent capsule endoscopy over a 3-year period. RESULTS Mucosal changes were found to be significantly more common in the cirrhotic patients than in the control patients (67.5% vs. 0, p < 0.001). The lesions included telangiectasias or angiodysplastic-like lesions in 9 (24.3%) patients, red spots in 23 (62.2%), and varices in 3 (8.1%). Active bleeding was seen during endoscopic examinations in 4 (10.8%) patients. A comparison of patients with and those without PHE showed that grade 2+ or larger esophageal varices, portal gastropathy, portal colonopathy, and Child-Pugh class C cirrhosis were all significantly associated with PHE. There were no differences between these two groups of patients with regard to the etiology of cirrhosis, gender, or history of esophageal variceal bleeding. CONCLUSIONS Mucosal abnormalities in portal jejunopathy include edema, erythema, and vascular lesions findings. A standardized grading system to classify the endoscopic appearance and the severity of portal enteropathy is proposed. The clinical import of these changes remains to be explained.

miR-519d overexpression is associated with human obesity.

Obesity is a consequence of imbalance of food intake and energy expenditure that results in storage of energy as fat, primarily in adipose tissue. MicroRNAs are non‐coding RNAs that regulate gene expression in metabolic pathways and they are also involved in fat‐cell development. The aim of this study was to evaluate whether microRNA dysfunction contributes to obesity. We analyzed, by microarray, the expression profile of 1,458 microRNAs in subcutaneous adipose tissue (SAT) from nondiabetic severely obese (n = 20) and nonobese adults (n = 8). Among 42 differently expressed microRNAs, we confirmed by reverse‐transcription PCR (RT‐PCR) that miR‐519d was overexpressed whereas the protein levels of peroxisome proliferator‐activated receptor‐α (PPARA) (a predicted miR 519d target) were lower, at western analysis, in severely obese vs. nonobese subjects. We also show that miR‐519d specifically and dose‐dependently suppressed translation of the PPARA protein, and increased lipid accumulation during preadipocyte differentiation. Because PPARA plays a central role in fatty acid homeostasis, and in the transcriptional regulation of genes that are necessary for maintenance of the redox balance during the oxidative catabolism of fatty acids, we suggest that PPARA loss and miR‐519d overexpression could be associated with metabolic imbalance and subsequent adipocyte hypertrophy in SAT during obesity.

Proinflammatory stimuli activates human-derived enteroglial cells and induces autocrine nitric oxide production.

Background  Enteric glial cells (EGCs) have been recently indicated as key regulators of intestinal inflammation in animals. Whether or not this is true and how these cells participate to inflammatory responses in humans is unknown.

In vivo characterisation of superficial colorectal neoplastic lesions with high-resolution probe-based confocal laser endomicroscopy in combination with video-mosaicing: A feasibility study to enhance routine endoscopy

BACKGROUND Recent technological advances in miniaturisation have allowed for a confocal scanning microscope to be integrated into trans-endoscopic probes enabling endoscopists to collect in vivo virtual biopsies of the gastrointestinal mucosa during endoscopy. AIMS The aim of the present study was to assess prospectively the clinical applicability and predictive power of a probe-based confocal laser endomicroscopy for the in vivo diagnosis of colorectal neoplasia. METHODS Patients with evidence of colorectal superficial neoplasia at routine endoscopy, were included prospectively in this study. Lesions were identified using white-light endoscopy followed by pCLE imaging recorded by a Coloflex UHD-type probe. The images were interpreted as either neoplastic or not according to vascular and cellular changes. pCLE readings were then compared with histopathological results from endoscopically resected lesions and/or targeted biopsy specimens. RESULTS A total of 32 lesions were identified in 20 consecutive patients. Histopathology diagnosis was of adenomas in 19 cases, hyperplastic polyps in 11 cases and adenocarcinoma in 2 cases. For the detection of neoplastic tissue pCLE had a sensitivity of 100%, a specificity of 84.6%, an accuracy of 92.3, a PPV of 90.5% and a NPV of 100%. CONCLUSIONS pCLE permits high-quality imaging, enabling prediction of intraepithelial neoplasia with a high level of accuracy.

CD133 and CD44 Cell surface markers do not identify cancer stem cells in primary human gastric tumors

Emerging evidence suggests that tumors contain and are driven by a cellular component that displays stem cell properties, the so‐called cancer stem cells (CSCs). CSCs have been identified in several solid human cancers; however, there are no data about CSCs in primary human gastric cancer (GC). By using CD133 and CD44 cell surface markers we investigated whether primary human GCs contain a cell subset expressing stem‐like properties and whether this subpopulation has tumor‐initiating properties in xenograft transplantation experiments. We examined tissues from 44 patients who underwent gastrectomy for primary GC. The tumorigenicity of the cells separated by flow cytometry using CD133 and CD44 surface markers was tested by subcutaneous or intraperitoneum injection in NOD/SCID and nude mice. GCs included in the study were intestinal in 34 cases and diffuse in 10 cases. All samples contained surface marker‐positive cells: CD133+ mean percentage 10.6% and CD133+/CD44+ mean percentage 27.7%, irrespective of cancer phenotype or grade of differentiation. Purified CD133+ and CD133+/CD44+ cells, obtained in sufficient number only in 12 intestinal type GC cases, failed to reproduce cancer in two mice models. However, the unseparated cells produced glandular‐like structures in 70% of the mice inoculated. In conclusion, although CD133+ and CD133+/CD44+ were detectable in human primary GCs, they neither expressed stem‐like properties nor exhibited tumor‐initiating properties in xenograft transplantation experiments. J. Cell. Physiol. 227: 2686–2693, 2012.

Diagnostic accuracy of confocal laser endomicroscopy in diagnosing dysplasia in patients affected by long-standing ulcerative colitis

AIM To evaluate the diagnostic accuracy of confocal laser endomicroscopy (CLE) for the detection of dysplasia in long-standing ulcerative colitis (UC). METHODS We prospectively performed a surveillance colonoscopy in 51 patients affected by long-standing UC. Also, in the presence of macroscopic areas with suspected dysplasia, both targeted contrasted indigo carmine endoscopic assessment and probe-based CLE were performed. Colic mucosal biopsies and histology, utilised as the gold standard, were assessed randomly and on visible lesions, in accordance with current guidelines. RESULTS Fourteen of the 51 patients (27%) showed macroscopic mucosal alterations with the suspected presence of dysplasia, needing chromoendoscopic and CLE evaluation. In 5 macroscopically suspected cases, the presence of dysplasia was confirmed by histology (3 flat dysplasia; 2 DALMs). No dysplasia/cancer was found on any of the outstanding random biopsies. The diagnostic accuracy of CLE for the detection of dysplasia compared to standard histology was sensitivity 100%, specificity 90%, positive predictive value 83% and negative predictive value 100%. CONCLUSION CLE is an accurate tool for the detection of dysplasia in long-standing UC and shows optimal values of sensitivity and negative predictivity. The scheduled combined application of chromoendoscopy and CLE could maximize the endoscopic diagnostic accuracy for diagnosis of dysplasia in UC patients, thus limiting the need for biopsies.

Global DNA hypomethylation is an early event in Helicobacter pylori-related gastric carcinogenesis

Aim Cancer, particularly gastric cancer (GC), is prevalently an epigenetic phenomenon that is dependent on an altered DNA methylation pattern. In gastric carcinogenesis, many genes show aberrant methylation; however, none of them may be used as a biomarker of cancer risk and progression. The authors aimed to evaluate the global DNA methylation of gastric mucosa in Helicobacter pylori (Hp)-related chronic gastritis, in GC and in 10 patients with preneoplastic lesions (ie, atrophy and intestinal metaplasia) followed up for 10 years. Methods The authors analysed 93 dyspeptic patients who underwent upper endoscopy, 41 surgical GC samples and 10 patients with preneoplastic gastric lesions followed up for 10 years after successful Hp eradication therapy. Global DNA methylation status and surrogate markers of cell proliferation and apoptosis were evaluated by immunohistochemistry using the anti-5-methylcytosine (5-MC), anti-Ki-67 and anti-p53 (anti-apoptotic marker)-specific antibodies, respectively. Results Global DNA methylation of gastric mucosa gradually decreased from normal mucosa to Hp-positive gastritis, Hp-positive chronic atrophic gastritis, independent of Cag-A status and GC; however, the variation was significant (p<0.05) only between Hp-negative subjects and Hp-positive chronic gastritis. Interestingly, the 5-MC immunostaining was absent in areas of intestinal metaplasia. In the 10 patients with preneoplastic lesions, global DNA methylation decreased over time despite the eradication of Hp infection, but reached significance only at 10 years versus baseline. The 5-MC immunostaining negatively correlated with Ki-67 and p53 expression in all groups. Conclusion Global DNA hypomethylation is an early molecular event in Hp-related gastric carcinogenesis. Further studies with more cases and a longer follow-up are needed to establish the potential GC predictive role of DNA hypomethylation.

Rapid "breath-print" of liver cirrhosis by proton transfer reaction time-of-flight mass spectrometry. A pilot study.

The aim of the present work was to test the potential of Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) in the diagnosis of liver cirrhosis and the assessment of disease severity by direct analysis of exhaled breath. Twenty-six volunteers have been enrolled in this study: 12 patients (M/F 8/4, mean age 70.5 years, min-max 42–80 years) with liver cirrhosis of different etiologies and at different severity of disease and 14 healthy subjects (M/F 5/9, mean age 52.3 years, min-max 35–77 years). Real time breath analysis was performed on fasting subjects using a buffered end-tidal on-line sampler directly coupled to a PTR-ToF-MS. Twelve volatile organic compounds (VOCs) resulted significantly differently in cirrhotic patients (CP) compared to healthy controls (CTRL): four ketones (2-butanone, 2- or 3- pentanone, C8-ketone, C9-ketone), two terpenes (monoterpene, monoterpene related), four sulphur or nitrogen compounds (sulfoxide-compound, S-compound, NS-compound, N-compound) and two alcohols (heptadienol, methanol). Seven VOCs (2-butanone, C8-ketone, a monoterpene, 2,4-heptadienol and three compounds containing N, S or NS) resulted significantly differently in compensate cirrhotic patients (Child-Pugh A; CP-A) and decompensated cirrhotic subjects (Child-Pugh B+C; CP-B+C). ROC (Receiver Operating Characteristic) analysis was performed considering three contrast groups: CP vs CTRL, CP-A vs CTRL and CP-A vs CP-B+C. In these comparisons monoterpene and N-compound showed the best diagnostic performance. Conclusions Breath analysis by PTR-ToF-MS was able to distinguish cirrhotic patients from healthy subjects and to discriminate those with well compensated liver disease from those at more advanced severity stage. A breath-print of liver cirrhosis was assessed for the first time.

Potent relaxant effect of a Celastrus paniculatus extract in the rat and human ileum

ETHNOPHARMACOLOGICAL IMPORTANCE Celastrus paniculatus Willd. (Celastraceae) is an Ayurvedic remedy used for the treatment of a number of diseases, including bowel spasms. AIM OF THE STUDY To investigate the mode of the relaxing action of a methanolic extract prepared from the seeds of Celastrus paniculatus (CPE, 0.0001-10 microg/mL) in the rat ileum and to try to confirm on human tissues the intestinal pharmacological activity of the extract. MATERIALS AND METHODS The relaxant effect of CPE was studied in vitro by evaluating its effect on the spontaneous contractions of the isolated ileum. RESULTS CPE exerted a tetrodotoxin- and omega-conotoxin-resistant inhibitory effect on rat ileum motility (IC(50): 0.24+/-0.02 microg/mL; E(max): 99.0+/-0.60%). The inhibitory effect was reduced by nifedipine but not by cyclopiazonic acid. Experiments with specific antagonists enabled us to exclude the involvement of the main endogenous spasmogenic (i.e. acetylcholine and tachykinins) and relaxing (noradrenaline, nitric oxide, ATP) compounds. CPE also relaxed the isolated human ileum (IC(50): 0.26+/-0.02 microg/mL; E(max): 99.1+/-0.46%). CONCLUSION It is concluded that (i) CPE exerted a powerful myogenic and L-type Ca(2+)-dependent relaxing effect in the isolated rat ileum and that (ii) the human ileum is sensitive to the inhibitory effect of CPE. If confirmed in vivo, our data could explain the traditional use of this herb in the treatment of intestinal spasms.

Endocrine carcinoma of the major papilla: Report of two cases and review of the literature

To date, about 100 cases of ampullary NET are reported in International literature. These tumors can cause symptoms mainly secondary to their periampullary location. Up to 25% of patients have von Recklinghausens disease. Carcinoid syndrome is uncommon, unless hepatic metastasis is present. Determination of histopathology is of utmost importance and involves specific immunohistochemical staining. The published data indicate that these tumors, metastasize in approximately half of cases irrespective of primary tumor size. Therefore, radical excision in the form of pancreaticoduodenectomy is recommended regardless of tumor size. Local excision should be confined to patients unable to tolerate more extensive surgery. We here report two case of ampullary neuroendocrine tumors presenting as melena and painless jaundice respectively in a 51-year old man and in a 54-year old man and review the relevant literature, giving special attention to the morphologic features, clinical characteristics, and treatment modalities associated with this disease process.