Federica Villa

Video capsule enteroscopy in the diagnosis of celiac disease : a multicenter study

OBJECTIVES:Duodenal biopsy is the current gold standard for diagnosis of celiac disease. Videocapsule endoscopy examines the entire small bowel and allows visualization of mucosal villi. We evaluated the potential of videocapsule endoscopy in assessing the severity and extent of mucosal changes in patients with suspected celiac disease.METHODS:Consecutive patients with signs/symptoms suggesting celiac disease and positive anti-gliadin and/or anti-endomysial and/or anti-tissue transglutaminase antibodies underwent upper gastrointestinal endoscopy and videocapsule endoscopy. Duodenal biopsies were classified according to modified Marshs criteria. Capsule findings were evaluated for the presence of lesions compatible with celiac disease (scalloping of duodenal folds, fissures, flat mucosa, and mosaic appearance).RESULTS:Forty-three patients were studied. Duodenal histology was normal in 11 and compatible with celiac disease in 32. Using duodenal histology as the gold standard, the performance characteristics of capsule endoscopy for the diagnosis of celiac disease were: sensitivity 87.5% (95% CI 76.1–98.9%), specificity 90.9% (95% CI 81.0–100%), positive predictive value 96.5% (95% CI 90.1–100%), negative predictive value 71.4% (95% CI 55.8–87%), positive and negative likelihood ratios 9.6 and 0.14, respectively. Eighteen patients had mucosal changes extending beyond the duodenum, involving the entire small bowel in three. These patients tended to have more severe symptoms, but the difference was not statistically significant. Interobserver agreement for the diagnosis of celiac disease by capsule endoscopy ranged between 79.2 and 94.4%; kappa values ranged between 0.56 and 0.87.CONCLUSIONS:Videocapsule endoscopy shows good sensitivity and excellent specificity for the detection of villous atrophy in patients with suspected celiac disease.

Small bowel capsule endoscopy in clinical practice: a multicenter 7-year survey

Background and aim Data about small bowel capsule endoscopy (SBCE) come from studies involving small and highly selected populations. The study aim was to describe extent of use, indications, results, complications, and practical issues of SBCE in clinical practice in a Northern Italian Region (Lombardia). Materials and methods Twenty-three out of 29 invited centers fulfilled a specific questionnaire. Results Between 2001 and 2008, 2921 procedures were performed and both the number of centers performing SBCE (from 5 to 29) and the number of SBCE (from 7.2 to 69.2 per month) increased steadily. The main indications for SBCE were: obscure gastrointestinal bleeding (OGIB) (43.4%), unexplained anemia (23.9%), suspected Crohns disease (7.8%) and abdominal pain (5.3%). Overall, SBCE was positive in 50% of cases, negative in 36% and undefined in 14%. The highest diagnostic yields were observed in patients with OGIB (62.5%), polypoid syndromes (74.1%), known (54.8%) or suspected (47.3%) inflammatory bowel disease, while the yields were low in patients examined for chronic diarrhea (27.4%) and abdominal pain (14.9%), 61 patients (2.1%) experienced capsule retention. Thirty-two of them eventually excreted the capsule naturally while endoscopic or surgical retrieval was necessary in 29 (1%) (in two because of obstruction). Conclusion Over a period of 7 years the use of SBCE in Lombardia increased steadily confirming, in clinical practice, a high diagnostic yield and an acceptable safety profile.

Feasibility of Removing Surface Deposits on Stone Using Biological and Chemical Remediation Methods

The study was conducted on alterations found on stone artwork and integrates microbial control and a biotechnological method for the removal of undesirable chemical substances. The Demetra and Cronos sculptures are two of 12 stone statues decorating the courtyard of the Buonconsiglio Castle in Trento (Italy). An initial inspection of the statues revealed putative black crusts and highlighted the microbial contamination causing discoloration. In 2006, the Cultural Heritage Superintendence of Trento commissioned us to study and remove these chemical and biological stains. Stereomicroscopy characterised the stone of the sculptures as oolitic limestone, and infrared analyses confirmed the presence of black crusts. To remove the black crusts, we applied a remediation treatment of sulphate-reducing bacteria, which removes the chemical alteration but preserves the original stone and the patina noble. Using traditional and biomolecular methods, we studied the putative microbial contamination and confirmed the presence of biodeteriogens and chose biocide Biotin N for the removal of the agents causing the discolouration. Denaturing gradient gel electrophoresis fluorescent in situ hybridisation established that Cyanobacteria and green algae genera were responsible for the green staining whereas the black microbial contamination was due to dematiaceous fungi. After the biocide Biotin N treatment, we applied molecular methods and demonstrated that the Cyanobacteria, and most of the green algae and dematiaceous fungi, had been efficiently removed. The reported case study reveals that conservators can benefit from an integrated biotechnological approach aimed at the biocleaning of chemical alterations and the abatement of biodeteriogens.

Biofilm Formation in Food Processing Environments is Still Poorly Understood and Controlled

The presence of undesirable biofilms on food processing contact surfaces may lead to: (1) transmission of diseases; (2) food spoilage; (3) shortened time between cleaning events; (4) contamination of product by nonstarter bacteria; (5) metal corrosion in pipelines and tanks; (6) reduced heat transfer efficacy or even obstruction of the heat equipment. Despite the significant problems caused by biofilms in the food industry, biofilm formation in these environments is still poorly understood and effective control of biofilms remains challenging. Although it is understood that cell attachment and biofilm formation are influenced by several factors, including type of strain, chemical–physical properties of the surface, temperature, growth media and the presence of other microorganisms, some conflicting statements can be retrieved from the literature and there are no general trends yet that allow us to easily predict biofilm development. It is likely that still unexplored interaction of factors may be more critical than the effect of a single parameter. New alternative biofilm control strategies, such as biocontrol, use of enzymes and phages and cell-to-cell communication interference, are now available that can reduce the use of chemical agents. In addition, as preventing biofilm formation is a more efficient strategy than controlling mature biofilm, the use of surface-modified materials have been suggested. These strategies may better reveal their beneficial potential when the ecological complexity of biofilms in food environments is addressed.

Increased thrombin generation in inflammatory bowel diseases

BACKGROUND Inflammatory bowel diseases (IBD) are characterized by an increased thrombotic risk of uncertain etiology. Endogenous thrombin potential (ETP), a parameter of the thrombin generation curve, represents a new tool in the evaluation of thrombotic and bleeding disorders. AIMS To study ETP in IBD patients and to correlate the results with clinical and biochemical features. METHODS Seventy-four IBD patients (37 ulcerative colitis and 37 Crohns disease) and 74 sex- and age-matched healthy individuals. ETP was measured upon activation of coagulation with small amounts of tissue factor and phospholipids in the presence or absence of thrombomodulin; results were expressed as nM thrombin.minutes. RESULTS Mean+/-SD ETP values were significantly higher in patients (1,499+/-454) than controls (1,261+/-385) (p<0.001) only when the test was performed in the presence of thrombomodulin. ETP evaluated as ratio (with/without thrombomodulin), taken as an index of hypercoagulability, was significantly higher in patients (0.69+/-0.14) than controls (0.62+/-0.18) (p<0.006). Patients with increased C-reactive protein (CRP) had significantly higher mean ETP (1,721+/-458) than those with normal CRP (1,357+/-394) or controls (1,261+/-385) (p<0.001). Patients who at the time of blood sampling were classified as having a clinically active disease had ETP higher than those who were quiescent (1,655+/-451 versus 1,388+/-427, p<0.001) or controls (1,261+/-385, p<0.001). CONCLUSIONS ETP measured in the presence of thrombomodulin or as ratio (with/without thrombomodulin) is increased in IBD patients, mainly in those with increased CRP or active disease. It may be considered as a candidate test for prospective studies aimed at assessing the risk of thrombosis in IBD patients.

Hindering biofilm formation with zosteric acid.

The antifoulant, zosteric acid, was synthesized using a non-patented process. Zosteric acid at 500 mg l−1 caused a reduction of bacterial (Escherichia coli, Bacillus cereus) and fungal (Aspergillus niger, Penicillium citrinum) coverage by 90% and 57%, respectively. Calculated models allowed its antifouling activity to be predicted at different concentrations. Zosteric acid counteracted the effects of some colonization-promoting factors. Bacterial and fungal wettability was not affected, but the agent increased bacterial motility by 40%. A capillary accumulation test showed that zosteric acid did not act as a chemoeffector for E. coli, but stimulated a chemotactic response. Along with enhanced swimming migration of E. coli in the presence of zosteric acid, staining showed an increased production of flagella. Reverse transcriptase-PCR revealed an increased transcriptional level of the fliC gene and isolation and quantification of flagellar proteins demonstrated a higher flagellin amount. Biofilm experiments confirmed that zosteric acid caused a significant decrease in biomass (−92%) and thickness (−54%).

Estrogenic control of monoamine oxidase A activity in human neuroblastoma cells expressing physiological concentrations of estrogen receptor

Several lines of evidence support the hypothesis of a role played by estrogens in the manifestation of affective disorders in women. The analysis of the mechanism of action of a number of antidepressant drugs clearly demonstrated the involvement of the catecholaminergic system in the etiology of these complex behavioral pathologies. The present in vitro study was therefore undertaken to investigate the presence of a functional link between estrogen and catecholamine metabolism in cells of neural origin. The model system utilized was a human neuroblastoma cell line which was obtained by stable transfection of the estrogen receptor cDNA (SK-ER3). The present study shows that in SK-ER3 activation of the estrogen receptor correlates with a marked decrease in monoamine oxidase A activity. This effect is observed following treatment with a physiological concentration of 17 beta-estradiol and can be blocked by the specific antagonist of the steroid receptor, ICI 182,780. Dibutyryl cyclic AMP acting, like estrogens, on the state of differentiation of SK-ER3 cells did not affect monoamine oxidase A activity. The present study provides strong evidence of a strict relationship between estrogen receptor and monoamine oxidase A activity in human cells of neural origin, thus favoring the hypothesis of an antidepressive effect of estrogens exerted via inhibition of the monoamine oxidative pathway.

Microbial Deterioration of Artistic Tiles from the Façade of the Grande Albergo Ausonia & Hungaria (Venice, Italy)

The Grande Albergo Ausonia & Hungaria (Venice Lido, Italy) has an Art Nouveau polychrome ceramic coating on its façade, which was restored in 2007. Soon after the conservation treatment, many tiles of the façade decoration showed coloured alterations putatively attributed to the presence of microbial communities. To confirm the presence of the biological deposit and the stratigraphy of the Hungaria tiles, stereomicroscope, optical and environmental scanning electron microscope observations were made. The characterisation of the microbial community was performed using a PCR–DGGE approach. This study reported the first use of a culture-independent approach to identify the total community present in biodeteriorated artistic tiles. The case study examined here reveals that the coloured alterations on the tiles were mainly due to the presence of cryptoendolithic cyanobacteria. In addition, we proved that the microflora present on the tiles was generally greatly influenced by the environment of the Hungaria hotel. We found several microorganisms related to the alkaline environment, which is in the range of the tile pH, and related to the aquatic environment, the presence of the acrylic resin Paraloid B72® used during the 2007 treatment and the pollutants of the Venice lagoon.

Plant-derived bioactive compounds at sub-lethal concentrations: towards smart biocide-free antibiofilm strategies

Biofilm resistance to biocides is becoming a global issue with an impact on many fields, including health care, agriculture, the environment, society and industry. Plants offer a virtually inexhaustible and sustainable resource of very interesting classes of biologically active, low-molecular-weight compounds (parvome). In the past, the plant parvomes were screened mainly for their lethal effects, disregarding concentrations and ecologically relevant functions of these molecules in the natural context. Testing sub-lethal concentrations of plant-derived compounds mimicking environmental levels may be critical to reveal mechanisms subtler than the killing activity, e.g. those influencing the multicellular behavior, offering an elegant way to develop novel biocide-free antibiofilm strategies. In a cross-disciplinary fashion, we illustrated recent successes of sub-lethal concentrations of plant-derived compounds, their ecological insight, pro et contra, future directions and impacts, envisioning implications for policy making and resource management.

A simple and reliable methodology to detect egg white in art samples

A protocol for a simple and reliable dot-blot immunoassay was developed and optimized to test work of art samples for the presence of specific proteinaceus material (i.e. ovalbumin-based). The analytical protocol has been extensively set up with respect, among the other, to protein extraction conditions, to densitometric analysis and to the colorimetric reaction conditions. Feasibility evaluation demonstrated that a commercial scanner and a free image analysis software can be used for the data acquisition and elaboration, thus facilitating the application of the proposed protocol to commonly equipped laboratories and to laboratories of museums and conservation centres. The introduction of method of standard additions in the analysis of fresh and artificially aged laboratory-prepared samples, containing egg white and various pigments, allowed us to evaluate the matrix effect and the effect of sample aging and to generate threshold density values useful for the detection of ovalbumin in samples from ancient works of art. The efficacy of the developed dot-blot immunoassay was proved testing microsamples from 13th–16th century mural paintings of Saint Francesco Church in Lodi (Italy). Despite the aging, the altered conditions of conservation, the complex matrix, and the micro-size of samples, the presence of ovalbumin was detected in all those mural painting samples where mass-spectrometry-based proteomic analysis unambiguously detected ovalbumin peptides.