Comprehensive Proteomics Analysis of the Hemolymph Composition of Sugar-Fed Aedes aegypti Female and Male Mosquitoes

In arthropods, hemolymph carries immune cells and solubilizes and transports nutrients, hormones, and other molecules that are involved in diverse physiological processes including immunity, metabolism, and reproduction. However, despite such physiological importance, little is known about its composition. We applied mass spectrometry-based label-free quantification approaches to study the proteome of hemolymph perfused from sugar-fed female and male Aedes aegypti mosquitoes. A total of 1403 proteins were identified, out of which 447 of them were predicted to be extracellular. In both sexes, almost half of these extracellular proteins were predicted to be involved in defense/immune response, and their relative abundances (based on their intensity-based absolute quantification, iBAQ) were 37.9 and 33.2%, respectively. Interestingly, among them, 102 serine proteases/serine protease-homologues were identified, with almost half of them containing CLIP regulatory domains. Moreover, proteins belonging to families classically described as chemoreceptors, such as odorant-binding proteins (OBPs) and chemosensory proteins (CSPs), were also highly abundant in the hemolymph of both sexes. Our data provide a comprehensive catalogue of A. aegypti hemolymph basal protein content, revealing numerous unexplored targets for future research on mosquito physiology and disease transmission. It also provides a reference for future studies on the effect of blood meal and infection on hemolymph composition.

Consumer acceptance for sheep milk-based yogurt-Evidence from a large sample of Italian consumers

Testing consumer acceptance for a new product, such as the sheep milk-based yogurt, provides a measure of its market success, thus it informs producers on the effectiveness of their decision to transform sheep milk into yogurt to increase their revenues. This work explores to what extent consumers accept sheep milk-based yogurt and tests the role of personal-related factors and product-related features on shaping its acceptance. The study collects data from a representative sample of Italian yogurt consumers, and data are then analyzed via a logistic regression. Results show that male, highly educated, and high-income consumers are more likely than others to accept sheep milk-based yogurt. Findings suggest that consumers' food neophobia and variety seeking traits play a pivotal role in affecting consumer acceptance. Lastly, interest in nutritional and health-related yogurt features increases the probability of accepting sheep milk-based yogurt. Thus, sheep milk-based yogurt should be targeted at high-end male consumers and those interested in nutritional and health-related aspects of yogurt. Informing consumers about the sheep milk yogurt properties may further increase its acceptance and curb food neophobia, which we found to be one of the main barriers for the product acceptance. Future studies will explore consumer acceptance by using a real product and taste experiments.

Coupled induction of prophage and virulence factors during tick transmission of the Lyme disease spirochete

The alternative sigma factor RpoS plays a central role in the critical host-adaptive response of the Lyme disease spirochete, Borrelia burgdorferi. We previously identified bbd18 as a negative regulator of RpoS but could not inactivate bbd18 in wild-type spirochetes. In the current study we employed an inducible bbd18 gene to demonstrate the essential nature of BBD18 for viability of wild-type spirochetes in vitro and at a unique point in vivo. Transcriptomic analyses of BBD18-depleted cells demonstrated global induction of RpoS-dependent genes prior to lysis, with the absolute requirement for BBD18, both in vitro and in vivo, circumvented by deletion of rpoS. The increased expression of plasmid prophage genes and the presence of phage particles in the supernatants of lysing cultures indicate that RpoS regulates phage lysis-lysogeny decisions. Through this work we identify a mechanistic link between endogenous prophages and the RpoS-dependent adaptive response of the Lyme disease spirochete.

Ultrasonographic diagnosis of ileo-ileal intussusception secondary to Vanek's tumor

Intussusception is a common condition of bowel obstruction in pediatric patients. However, 5% of all cases occur in adults, mostly aged over fifty, with no difference based on sex, representing about 1% of all causes of bowel obstruction. Compared to pediatric population, it is triggered by a pathologic lead point in about 85% of cases, represented in 60% of cases by malignant and benign neoplasms. Among these neoplasms, an inflammatory fibroid polyp (IFP), a benign neoplastic submucosal lesion also known as Vanek's tumor, is considered a very uncommon cause of adult intussusception. Clinical presentation could differ by location and size of tumor, and may include abdominal pain, nausea, vomiting, diarrhea or constipation, bleeding, weight loss, palpable abdominal mass, bowel obstruction, and gastrointestinal bleeding. Considering its common and non-specific symptoms, radiologic imaging plays a key role in the diagnosis of an IFP, especially computed tomography (CT) scan, which represents the most sensitive modality to confirm intussusception. However, bowel sonography (BS) has become an accurate procedure in various pathological intestinal diseases, also including intussusception. In this paper, we report a rare case of ileo-ileal intussusception secondary to Vanek's tumor diagnosed by BS.

Short stature and combined immunodeficiency associated with mutations in RGS10

We report the clinical and molecular phenotype of three siblings from one family, who presented with short stature and immunodeficiency and carried uncharacterized variants in RGS10 (c.489_491del:p.E163del and c.G511T:p.A171S). This gene encodes regulator of G protein signaling 10 (RGS10), a member of a large family of GTPase-activating proteins (GAPs) that targets heterotrimeric G proteins to constrain the activity of G protein-coupled receptors, including receptors for chemoattractants. The affected individuals exhibited systemic abnormalities directly related to the RGS10 mutations, including recurrent infections, hypergammaglobulinemia, profoundly reduced lymphocyte chemotaxis, abnormal lymph node architecture, and short stature due to growth hormone deficiency. Although the GAP activity of each RGS10 variant was intact, each protein exhibited aberrant patterns of PKA-mediated phosphorylation and increased cytosolic and cell membrane localization and activity compared to the wild-type protein. We propose that the RGS10 p.E163del and p.A171S mutations lead to mislocalization of the RGS10 protein in the cytosol, thereby resulting in attenuated chemokine signaling. This study suggests that RGS10 is critical for both immune competence and normal hormonal metabolism in humans and that rare RGS10 variants may contribute to distinct systemic genetic disorders.

Plasma dosage of ghrelin, IGF-1, GLP- 1 and leptin related to gastric emptying and esophageal pH-impedance in children with obesity

PURPOSE

The main aim of the study was to assess the relationship between leptin, ghrelin, insulin-like growth factor 1 (IGF-1), and glucagon-like peptide 1 (GLP-1) blood levels and gastric motility in children with obesity compared to healthy children. Secondary aims were to assess the possible association between these hormones and obesity, reflux impedance parameters, reflux symptoms, other GI disorders, and quality-of-life scores within the same groups.

METHODS

Children with obesity plus GERD symptoms and 2 control groups of children with obesity without GERD and healthy lean children aged 4-17 years underwent an auxological evaluation, an assessment of gastro-intestinal symptoms and quality of life, hormonal dosages, and an evaluation of gastric emptying time (GET) through 13C-octanoic acid breath test.

RESULTS

No significant association was found between hormones and gastric motility. Leptin and ghrelin levels were significantly associated with obesity parameters. No significant differences were found between GET and hormones of the patients with obesity, either with or without GERD.

CONCLUSION

Although we found an association between auxological parameters and both leptin and ghrelin levels, this association did not imply an effect on the upper GI motility. Therefore, our hypothesis that alterations of these hormones in children with obesity could affect gastric emptying, triggering GERD, was not supported by our data.

Efficacy of favipiravir (T-705) against Crimean-Congo hemorrhagic fever virus infection in cynomolgus macaques

Crimean-Congo hemorrhagic fever virus (CCHFV) is a widely distributed hemorrhagic fever virus found throughout Eastern Europe, Africa, the Middle East and Asia. It is spread through bites from infected ticks, animal husbandry and can also be acquired in the healthcare setting during care of infected patients. In humans, CCHFV can cause a sudden onset of a non-specific febrile illness that can rapidly progress to severe hemorrhagic manifestations. Currently, there is no widely available vaccine and although ribavirin has been suggested for the treatment of CCHFV, clinical efficacy in both animal models and humans is inconsistent suggesting more potent antivirals are needed for CCHFV. Favipiravir is approved in Japan for the treatment of influenza virus infections and has shown promise against other highly pathogenic RNA viruses including CCHFV with demonstrated efficacy in the type I interferon deficient mouse model. In this report we utilized the cynomolgus macaque model to evaluate the efficacy of once- and twice-daily favipiravir treatment against CCHFV infection. We found that favipiravir treatment suppressed viremia and viral shedding when treatment was initiated 24 h post-infection and viral burdens in key tissues trended lower in favipiravir-treated animals. Our data indicate that favipiravir has efficacy against CCHFV in vivo in a non-human primate model of infection.

Table grapes as functional food: Consumer preferences for health and environmental attributes

Consumers' interest towards food with healthy and sustainable characteristics is growing and companies try to address such trend through the supply of products with characteristics for which consumers show willingness to pay a premium price. Table grapes could be considered a product with functional characteristics since offer a wealth of health benefits due to their high nutrient and antioxidant contents. Moreover, its production and distribution are increasingly affected by sustainability concerns. On the basis of these considerations, the objective of this paper is to evaluate the consumer preferences for health and environmental attributes of table grapes. For this purpose, a nationwide survey was conducted in Italy using the Computer Assisted Web Interviewing (CAWI) method and the Best- Worst Scaling Method (BWS) for data analysis. The survey is divided into sections which consider, besides the socio-demographic characteristics of respondents, questions about their preferences related to specific attributes of table grapes (variety, color, seedless, organic or conventional production, origin) and to nutritional and sustainable characteristics reported on the label. Results could be of interest for companies which can focus their marketing strategies on specific characteristics of the product, and for policy makers who are asked to take decisions for public health.

On the effects of bilateral agreements in world wine trade

During the last decades there have been significant changes in trade regulations that are modifying the global trade of wine. The number of non-tariff measures (NTMs) adopted in the wine sector is relevant. Similarly, a large number of bilateral trade agreements have been adopted. Despite the regulation is heavy, the impact of these policy instruments on trade is not always clear, nor quantified at global scale. We investigate the effects that bilateral NTMs are showing on global imports of wine. In particular, we estimate a gravity model to explain how bilateral NTMs influence wine trade, and we disentangle these effects for different segments of the international market of wine. Our results suggest that bilateral NTMs tend to favour imports of wine. Differences emerge across market segments and types of regulations. In particular, the Technical Barriers to Trade favour (friction) bottled (bulk) wine; pre-shipment inspections enhance imports of bottled wine; the Sanitary and Phytosanitary Standards are the most trade-enhancing NTMs, regardless of the market segment.

Unique Francisella Phosphatidylethanolamine Acts as a Potent Anti-Inflammatory Lipid

Virulent Francisella tularensis subsp. tularensis (Ftt) is a dynamic, intracellular, bacterial pathogen. Its ability to evade and rapidly suppress host inflammatory responses is considered a key element for its profound virulence. We previously established that Ftt lipids play a role in inhibiting inflammation, but we did not determine the lipid species mediating this process. Here, we show that a unique, abundant, phosphatidylethanolamine (PE), present in Francisella, contributes to driving the suppression of inflammatory responses in human and mouse cells. Acyl chain lengths of this PE, C24: 0 and C10: 0, were key to the suppressive capabilities of Francisella PE. Addition of synthetic PE 24: 0-10: 0 resulted in the accumulation of PE in host cells for up to 24 h of incubation, and recapitulated the inhibition of inflammatory responses observed with native Ftt PE. Importantly, this novel PE significantly inhibited inflammatory responses driven by a medically and globally important flavivirus, dengue fever virus. Thus, targeting these lipids and/or the pathways that they manipulate represents a new strategy to combat immunosuppression engendered by Ftt, but they also show promise as a novel therapeutic intervention for significant viral infections.

Host immune status-specific production of gliotoxin and bis-methyl-gliotoxin during invasive aspergillosis in mice

Delayed diagnosis in invasive aspergillosis (IA) contributes to its high mortality. Gliotoxin (GT) and bis-methyl-gliotoxin (bmGT) are secondary metabolites produced by Aspergillus during invasive, hyphal growth and may prove diagnostically useful. Because IA pathophysiology and GT's role in virulence vary depending on the underlying host immune status, we hypothesized that GT and bmGT production in vivo may differ in three mouse models of IA that mimic human disease. We defined temporal kinetics of GT and bmGT in serum, bronchoalveolar lavage fluid (BALF) and lungs of A. fumigatus-infected chronic granulomatous disease (CGD), hydrocortisone-treated, and neutropenic mice. We harvested lungs for assessment of fungal burden, histology and GT/bmGT biosynthetic genes' mRNA induction. GT levels were higher in neutropenic versus CGD or steroid-treated lungs. bmGT was persistently detected only in CGD lungs. GT, but not bmGT, was detected in 71% of sera and 50% of BALF of neutropenic mice; neither was detected in serum/BALF of CGD or steroid-treated mice. Enrichment of GT in Aspergillus-infected neutropenic lung correlated with fungal burden and hyphal length but not induction of GT biosynthetic genes. In summary, GT is detectable in mouse lungs, serum and BALF during neutropenic IA, suggesting that GT may be useful to diagnose IA in neutropenic patients.

Hepatocellular carcinoma recurrence in patients with curative resection or ablation: impact of HCV eradication does not depend on the use of interferon

BACKGROUND

In HCV-infected cirrhotic patients with successfully treated early hepatocellular carcinoma (HCC), the time to HCC recurrence and the effects of sustained viral eradication (SVR) by interferon (IFN)-based or IFN-free regimens on HCC recurrence remain unclear.

AIM

To perform an indirect comparison of time to recurrence (TTR) in patients with successfully treated early HCC and active HCV infection with those of patients with SVR by IFN-based and by IFN-free regimens.

METHODS

We evaluated 443 patients with HCV-related cirrhosis and Barcelona Clinic Liver Cancer Stage A/0 HCC who had a complete radiological response after curative resection or ablation. Active HCV infection was present in 328, selected from the Italian Liver Cancer group cohort; 58 patients had SVR achieved by IFN-free regimens after HCC cure, and 57 patients had SVR achieved by IFN-based regimens after HCC cure. Individual data of patients in the last two groups were extracted from available publications.

RESULTS

TTR by Kaplan-Meier curve was significantly lower in patients with active HCV infection compared with those with SVR both by IFN-free (P = 0.02) and by IFN-based (P < 0.001) treatments. TTR was similar in patients with SVR by IFN-free or by IFN-based (P = 0.49) strategies.

CONCLUSION

In HCV-infected, successfully treated patients with early HCC, SVR obtained by IFN-based or IFN-free regimens significantly reduce tumour recurrence without differences related to the anti-viral strategy used.

CD8+ T cells produce a dialyzable antigen-specific activator of dendritic cells

Cellular lysates from PPD⁺ donors have been reported to transfer tuberculin reactivity to naïve recipients, but not diphtheria reactivity, and vice versa. A historically controversial topic, the terms "transfer factor" and "DLE" were used to characterize the reactivity-transferring properties of lysates. Intrigued by these reported phenomena, we found that the cellular extract derived from antigen-specific memory CD8⁺ T cells induces IL-6 from antigen-matched APCs. This ultimately elicits IL-17 from bystander memory CD8⁺ T cells. We have identified that dialyzable peptide sequences, S100a9, and the TCR β chain from CD8⁺ T cells contribute to the molecular nature of this activity. We further show that extracts from antigen-targeted T cells enhance immunity to Staphylococcus aureus and Candida albicans These effects are sensitive to immunization protocols and extraction methodology in ways that may explain past discrepancies in the reproducibility of passive cellular immunity.

Structure and Ligand-Binding Mechanism of a Cysteinyl Leukotriene-Binding Protein from a Blood-Feeding Disease Vector

Blood-feeding disease vectors mitigate the negative effects of hemostasis and inflammation through the binding of small-molecule agonists of these processes by salivary proteins. In this study, a lipocalin protein family member (LTBP1) from the saliva of Rhodnius prolixus, a vector of the pathogen Trypanosoma cruzi, is shown to sequester cysteinyl leukotrienes during feeding to inhibit immediate inflammatory responses. Calorimetric binding experiments showed that LTBP1 binds leukotrienes C4 (LTC4), D4 (LTD4), and E4 (LTE4) but not biogenic amines, adenosine diphosphate, or other eicosanoid compounds. Crystal structures of ligand-free LTBP1 and its complexes with LTC4 and LTD4 reveal a conformational change during binding that brings Tyr114 into close contact with the ligand. LTC4 is cleaved in the complex, leaving free glutathione and a C20 fatty acid. Chromatographic analysis of bound ligands showed only intact LTC4, suggesting that cleavage could be radiation-mediated.

Identification of a unique lipid from Francisella tularensis as an effective therapeutic for viral mediated inflammation

Francisella tularensis (FT) is a highly pathogenic bacterium which can cause acute, lethal disease following exposure to fewer than 20 bacteria. FT is a successful pathogen due to its ability to potently and rapidly suppress inflammatory responses in host cells. We previously established that crude lipid preparations from virulent FT dampen inflammation in vitro and in vivo, but did not characterize the active specie(s). Utilizing a variety of biochemical techniques, we identified one of the active lipids found in FT as a unique phosphatidylethanolamine (PE) consisting of tetracosanoyl and decanoyl acyl chains (PE2410). Similar to crude lipid, enriched PE2410 restricted production of cytokines in human and mouse cells stimulated with well-defined microbial ligands. PE2410 was also effective at dampening inflammation provoked by infection with West Nile Virus. Activity of PE2410 was dependent on presence of the host phosphatase SHP-1. Importantly, a synthetic version of the PE2410 mimicked the ability of natural PE2410 to inhibit inflammation triggered by a variety of sources. Together our data support use of PE2410 as a novel therapeutic for pathogenic inflammation triggered by viral, or other, infection.

Plasmodium Infection Is Associated with Impaired Hepatic Dimethylarginine Dimethylaminohydrolase Activity and Disruption of Nitric Oxide Synthase Inhibitor/Substrate Homeostasis

Inhibition of nitric oxide (NO) signaling may contribute to pathological activation of the vascular endothelium during severe malaria infection. Dimethylarginine dimethylaminohydrolase (DDAH) regulates endothelial NO synthesis by maintaining homeostasis between asymmetric dimethylarginine (ADMA), an endogenous NO synthase (NOS) inhibitor, and arginine, the NOS substrate. We carried out a community-based case-control study of Gambian children to determine whether ADMA and arginine homeostasis is disrupted during severe or uncomplicated malaria infections. Circulating plasma levels of ADMA and arginine were determined at initial presentation and 28 days later. Plasma ADMA/arginine ratios were elevated in children with acute severe malaria compared to 28-day follow-up values and compared to children with uncomplicated malaria or healthy children (p<0.0001 for each comparison). To test the hypothesis that DDAH1 is inactivated during Plasmodium infection, we examined DDAH1 in a mouse model of severe malaria. Plasmodium berghei ANKA infection inactivated hepatic DDAH1 via a post-transcriptional mechanism as evidenced by stable mRNA transcript number, decreased DDAH1 protein concentration, decreased enzyme activity, elevated tissue ADMA, elevated ADMA/arginine ratio in plasma, and decreased whole blood nitrite concentration. Loss of hepatic DDAH1 activity and disruption of ADMA/arginine homeostasis may contribute to severe malaria pathogenesis by inhibiting NO synthesis.

During a malaria infection, the vascular endothelium becomes more adhesive, permeable, and prone to trigger blood clotting. These changes help the parasite adhere to blood vessels, but endanger the host by obstructing blood flow through small vessels. Endothelial nitric oxide (NO) would normally counteract these pathological changes, but NO signalling is diminished malaria. NO synthesis is inhibited by asymmetric dimethylarginine (ADMA), a methylated derivative of arginine that is released during normal protein turnover. We found the ratio of ADMA to arginine to be elevated in Gambian children with severe malaria, a metabolic disturbance known to inhibit NO synthesis. ADMA was associated with markers of endothelial activation and impaired tissue perfusion. In parallel experiments using mice, the enzyme responsible for metabolizing ADMA, dimethylarginine dimethylaminohydrolase (DDAH), was inactivated after infection with a rodent malaria. Based on these studies, we propose that decreased metabolism of ADMA by DDAH might contribute to the elevated ADMA/arginine ratio observed during an acute episode of malaria. Strategies to preserve or increase DDAH activity might improve NO synthesis and help to prevent the vascular manifestations of severe malaria.

Resolution and quantification of arginine, monomethylarginine, asymmetric dimethylarginine, and symmetric dimethylarginine in plasma using HPLC with internal calibration

N(G) ,N(G) -dimethyl-l-arginine (asymmetric dimethylarginine, ADMA),N(G) -monomethyl-l-arginine (l-NMMA) and N(G) ,N(G') -dimethyl-l-arginine (symmetric dimethylarginine, SDMA) are released during hydrolysis of proteins containing methylated arginine residues. ADMA and l-NMMA inhibit nitric oxide synthase by competing with l-arginine substrate. All three methylarginine derivatives also inhibit arginine transport. To enable investigation of methylarginines in diseases involving impaired nitric oxide synthesis, we developed a high-performance liquid chromatography (HPLC) assay to simultaneously quantify arginine, ADMA, l-NMMA and SDMA. Our assay requires 12 μL of plasma and is ideal for applications where sample availability is limited. We extracted arginine and methylarginines with mixed-mode cation-exchange columns, using synthetic monoethyl-l-arginine as an internal standard. Metabolites were derivatized with ortho-phthaldialdeyhde and 3-mercaptopropionic acid, separated by reverse-phase HPLC and quantified with fluorescence detection. Standard curve linearity was ≥0.9995 for all metabolites. Inter-day coefficient of variation (CV) values were ≤5% for arginine, ADMA and SDMA in human plasma and for arginine and ADMA in mouse plasma. The CV value for l-NMMA was higher in human (10.4%) and mouse (15.8%) plasma because concentrations were substantially lower than ADMA and SDMA. This assay provides unique advantages of small sample volume requirements, excellent separation of target metabolites from contaminants and validation for both human and mouse plasma samples.

Salivary antigen-5/CAP family members are Cu2+-dependent antioxidant enzymes that scavenge O₂₋. and inhibit collagen-induced platelet aggregation and neutrophil oxidative burst

The function of the antigen-5/CAP family of proteins found in the salivary gland of bloodsucking animals has remained elusive for decades. Antigen-5 members from the hematophagous insects Dipetalogaster maxima (DMAV) and Triatoma infestans (TIAV) were expressed and discovered to attenuate platelet aggregation, ATP secretion, and thromboxane A2 generation by low doses of collagen (<1 μg/ml) but no other agonists. DMAV did not interact with collagen, glycoprotein VI, or integrin α2β1. This inhibitory profile resembles the effects of antioxidants Cu,Zn-superoxide dismutase (Cu,Zn-SOD) in platelet function. Accordingly, DMAV was found to inhibit cytochrome c reduction by O2[Symbol: see text] generated by the xanthine/xanthine oxidase, implying that it exhibits antioxidant activity. Moreover, our results demonstrate that DMAV blunts the luminescence signal of O2[Symbol: see text] generated by phorbol 12-myristate 13-acetate-stimulated neutrophils. Mechanistically, inductively coupled plasma mass spectrometry and fluorescence spectroscopy revealed that DMAV, like Cu,Zn-SOD, interacts with Cu(2+), which provides redox potential for catalytic removal of O2[Symbol: see text]. Notably, surface plasmon resonance experiments (BIAcore) determined that DMAV binds sulfated glycosaminoglycans (e.g. heparin, KD ~100 nmol/liter), as reported for extracellular SOD. Finally, fractions of the salivary gland of D. maxima with native DMAV contain Cu(2+) and display metal-dependent antioxidant properties. Antigen-5/CAP emerges as novel family of Cu(2+)-dependent antioxidant enzymes that inhibit neutrophil oxidative burst and negatively modulate platelet aggregation by a unique salivary mechanism.

Increased severity of dyspeptic symptoms related to mental stress is associated with sympathetic hyperactivity and enhanced endocrine response in patients with postprandial distress syndrome

BACKGROUND

Mental stress (MS) may alter gastric sensory-motor function. The aim of the study was to assess postprandial autonomic nervous system activity and stress hormones in response to acute mental stress in dyspeptic patients.

METHODS

A total of 25 patients with postprandial distress syndrome (PDS; 11 mol L(-1), age 35.9 ± 9.3 years) and 12 healthy controls (5 mol L(-1), age 25.8 ± 4.6 years) underwent electrogastrography and (13) C-octanoate gastric emptying study using a 480 kcal solid meal. Heart rate variability (LF/HF ratio) and corticotrophin-releasing factor, adrenocorticotropic hormone (ACTH), and cortisol serum levels were also evaluated. Dyspeptic symptoms were scored by analogue visual scale and expressed as symptoms total score (TS). The protocol was repeated twice in each subject, with and without a mental stress test before the meal.

KEY RESULTS

Mental stress significantly increased postprandial symptoms severity in patients (TS: stress 111 ± 18 vs basal 50 ± 10; P < 0.05). Low-/high-frequency component ratio was significantly higher in patients after MS at 120 min (stress 5.46 ± 0.41 vs basal 3.41 ± 0.64; P < 0.01) and 180 min (stress 5.29 ± 0.2 vs basal 3.58 ± 0.19; P < 0.05). During stress session, in patients we found a significantly higher ACTH level than baseline at 30, 60, 90, 150, 210, 240, and 270 min and a significantly higher cortisol level at 30, 60, 90, 120, 210, and 270 min. Gastric emptying rate and electrical activity were not influenced by MS.

CONCLUSIONS & INFERENCES

In PDS patients, administration of MS before meal increases symptoms severity by inducing sympathetic hyperactivity and increased stress hormones levels. As the gastric emptying looks not altered, we conclude that these neurohormonal responses mainly affect sensitive function.

The role of gut microbiota in the pathogenesis and management of allergic diseases

Allergy is defined as a hypersensitivity reaction due to specific antibody-mediated or cell-mediated immunologic mechanisms. Epidemiological studies are showing a dramatic increase of allergies in industrialized countries in the last few decades, while remaining stable in developing countries. In 1989 Strachan, hypothesized that the increase in allergic disorders was the result of a lack of infections in early infancy, and in 1998 Wold suggested that, rather than a decrease in viral or bacterial infections, an altered normal intestinal colonization pattern in infancy, could be responsible for the increase in allergies. Germ-free mice were shown to mount an exaggerated allergic airway reaction compared with that seen in colonized mice, indicating the important role of microbe-host interactions in the development of allergic diseases. Infants with food allergies are found to exhibit an imbalance between "beneficial"and potentially harmful bacteria, i.e., decreased Lactobacilli, Bifidobacteria and Enterococcus species and increased coliforms, Staphylococcus aureus and Clostridium species, suggesting that microbial inhabitants of the human body, may play either a pathogenic or protective role in allergies. Based on this data, many clinical trial addressing the use of probiotics in the context of allergic disorders, have been conducted in children. However, currently, no conclusive item may be drawn.

Gut--liver axis: the impact of gut microbiota on non alcoholic fatty liver disease

AIM

To examine the impact of gut microbiota on non alcoholic fatty liver disease (NAFLD) pathogenesis.

DATA SYNTHESIS

Emerging evidence suggests a strong interaction between gut microbiota and liver. Receiving approximately 70% of its blood supply from the intestine, the liver represents the first line of defence against gut-derived antigens. Intestinal bacteria play a key role in the maintenance of gut-liver axis health. Disturbances in the homeostasis between bacteria- and host-derived signals at the epithelial level lead to a break in intestinal barrier function and may foster "bacterial translocation", defined as the migration of bacteria or bacterial products from the intestinal lumen to mesenteric lymph nodes or other extraintestinal organs and sites. While the full repertoire of gut-derived microbial products that reach the liver in health and disease has yet to be explored, the levels of bacterial lipopolysaccharide, a component of the outer membrane of Gram-negative bacteria, are increased in the portal and/or systemic circulation in several types of chronic liver diseases. Derangement of the gut flora, particularly small intestinal bacterial overgrowth, occurs in a large percentage (20-75%) of patients with chronic liver disease. In addition, evidence implicating the gut-liver axis in the pathogenesis of metabolic liver disorders has accumulated over the past ten years.

CONCLUSIONS

Complex metabolic diseases are the product of multiple perturbations under the influence of triggering factors such as gut microbiota and diet, thus, modulation of the gut microbiota may represent a new way to treat or prevent NAFLD.

Gut--liver axis: the impact of gut microbiota on non alcoholic fatty liver disease

AIM

To examine the impact of gut microbiota on non alcoholic fatty liver disease (NAFLD) pathogenesis.

DATA SYNTHESIS

Emerging evidence suggests a strong interaction between gut microbiota and liver. Receiving approximately 70% of its blood supply from the intestine, the liver represents the first line of defence against gut-derived antigens. Intestinal bacteria play a key role in the maintenance of gut-liver axis health. Disturbances in the homeostasis between bacteria- and host-derived signals at the epithelial level lead to a break in intestinal barrier function and may foster "bacterial translocation", defined as the migration of bacteria or bacterial products from the intestinal lumen to mesenteric lymph nodes or other extraintestinal organs and sites. While the full repertoire of gut-derived microbial products that reach the liver in health and disease has yet to be explored, the levels of bacterial lipopolysaccharide, a component of the outer membrane of Gram-negative bacteria, are increased in the portal and/or systemic circulation in several types of chronic liver diseases. Derangement of the gut flora, particularly small intestinal bacterial overgrowth, occurs in a large percentage (20-75%) of patients with chronic liver disease. In addition, evidence implicating the gut-liver axis in the pathogenesis of metabolic liver disorders has accumulated over the past ten years.

CONCLUSIONS

Complex metabolic diseases are the product of multiple perturbations under the influence of triggering factors such as gut microbiota and diet, thus, modulation of the gut microbiota may represent a new way to treat or prevent NAFLD.

Risk factors in gastric cancer

STATE OF THE ART

Gastric cancer (GC) is still a major health problem worldwide due to its frequency, poor prognosis and limited treatment options. At present prevention is likely to be the most effective means of reducing the incidence and mortality from this disease. The most important etiological factors implicated in gastric carcinogenesis are diet and Helicobacter pylori (H. pylori) infection. High intake of salted, pickled or smoked foods, as well as dried fish and meat and refined carbohydrates significantly increased the risk of developing GC while fibers, fresh vegetables and fruit were found to be inversely associated with GC risk. Epidemiological investigations (retrospective, case-control and prospective) and several meta-analyses have demonstrated that concurrent or previous H. pylori infection is associated with an increased risk of GC in respect to uninfected people. H. pylori colonizes gastric mucosa where it induces a complex inflammatory and immune reaction that on time leads to a severe mucosal damage i.e., atrophy, intestinal metaplasia (IM) and dysplasia. The risk of GC is closely related to the grade and extension of gastric atrophy, IM and dysplasia.

PERSPECTIVES AND CONCLUSIONS

Today a plausible program for GC prevention means: (1) a correct dietary habit since childhood increasing vegetables and fruit intake, (2) a decrease of H. pylori spread improving family and community sanitation and hygiene, (3) a search and treat H. pylori strategy in offspring of GC, (4) a search and treat H. pylori strategy in patients with chronic atrophic gastritis and intestinal metaplasia (IM), (5) a careful endoscopic and histologic follow-up if precancerous lesions persist irrespective of H. pylori eradication.

Increased mucosal nitric oxide production in ulcerative colitis is mediated in part by the enteroglial-derived S100B protein

In the central nervous system glial-derived S100B protein has been associated with inflammation via nitric oxide (NO) production. As the role of enteroglial cells in inflammatory bowel disease has been poorly investigated in humans, we evaluated the association of S100B and NO production in ulcerative colitis (UC). S100B mRNA and protein expression, inducible NO synthase (iNOS) expression, and NO production were evaluated in rectal biopsies from 30 controls and 35 UC patients. To verify the correlation between S100B and NO production, biopsies were exposed to S100B, in the presence or absence of specific receptor for advanced glycation end-products (RAGE) blocking antibody, to measure iNOS expression and nitrite production. S100B and iNOS expression were evaluated after incubation of biopsies with lipopolysaccharides (LPS) + interferon-gamma (IFN-gamma) in the presence of anti-RAGE or anti-S100B antibodies or budesonide. S100B mRNA and protein expression, iNOS expression and NO production were significantly higher in the rectal mucosa of patients compared to that of controls. Exogenous S100B induced a significant increase in both iNOS expression and NO production in controls and UC patients; this increase was inhibited by specific anti-RAGE blocking antibody. Incubation with LPS + IFN-gamma induced a significant increase in S100B mRNA and protein expression, together with increased iNOS expression and NO production. LPS + IFN-gamma-induced S100B up-regulation was not affected by budesonide, while iNOS expression and NO production were significantly inhibited by both specific anti-RAGE and anti-S100B blocking antibodies. Enteroglial-derived S100B up-regulation in UC participates in NO production, involving RAGE in a steroid insensitive pathway.

Methodology and indications of H2-breath testing in gastrointestinal diseases: the Rome Consensus Conference

BACKGROUND

Breath tests represent a valid and non-invasive diagnostic tool in many gastroenterological conditions. The rationale of hydrogen-breath tests is based on the concept that part of the gas produced by colonic bacterial fermentation diffuses into the blood and is excreted by breath, where it can be quantified easily. There are many differences in the methodology, and the tests are increasingly popular.

AIM

The Rome Consensus Conference was convened to offer recommendations for clinical practice about the indications and methods of H2-breath testing in gastrointestinal diseases.

METHODS

Experts were selected on the basis of a proven knowledge/expertise in H2-breath testing and divided into Working Groups (methodology; sugar malabsorption; small intestine bacterial overgrowth; oro-coecal transit time and other gas-related syndromes). They performed a systematic review of the literature, and then formulated statements on the basis of the scientific evidence, which were debated and voted by a multidisciplinary Jury. Recommendations were then modified on the basis of the decisions of the Jury by the members of the Expert Group.

RESULTS AND CONCLUSIONS

The final statements, graded according to the level of evidence and strength of recommendation, are presented in this document; they identify the indications for the use of H2-breath testing in the clinical practice and methods to be used for performing the tests.

Low-dose aspirin reduces the gene expression of gastrokine-1 in the antral mucosa of healthy subjects

BACKGROUND

Gastrokine 1 (GKN1), one of the most abundant transcripts in normal stomach, is down-regulated by Helicobacter pylori infection. Aspirin (ASA), which is often used for secondary prevention of cardiovascular events, can damage gastric-duodenal mucosa within 1 or 2 h of ingestion.

AIM

To study the gastric mucosal expression of GKN1 during acute low-dose ASA consumption.

METHODS

Ten H. pylori-negative human volunteers took 100 mg ASA per day for 1 week, and underwent multiple upper GI endoscopies. GKN1 expression was analysed in antral and corpus mucosa by quantitative reverse-transcriptase polymerase chain reaction, western blot and immunohistochemistry (IHC). Gastric mucosal damage was detected endoscopically and histologically.

RESULTS

Gastrokine 1 was similarly expressed in both antral and corpus mucosa. The use of low-dose ASA led to a significant decrease (3.07 a.u. vs. 0.23 a.u., P < 0.001) in antrum at day 7, while GKN1 transcript levels in corpus mucosa were slightly elevated (twofold, P < 0.005). Western blot and IHC confirmed these changes at the protein level. Furthermore, IHC revealed a vesicular staining pattern in the cytoplasm for GKN1 that was confirmed by transfected human gastric adenocarcinoma cell line expressing GKN1.

CONCLUSION

Our data demonstrated that low-dose ASA downregulates GKN1 expression specifically in antral mucosa.

Failure of first-line eradication treatment significantly increases prevalence of antimicrobial-resistant Helicobacter pylori clinical isolates

OBJECTIVES

Helicobacter pylori infection is a major health problem worldwide, and effective eradication of the infection is mandatory. The efficacy of recommended eradication regimens is approximately 70%. To avoid treatment failure and the consequent development of secondary resistance(s), it is important to choose the most appropriate first-line treatment regimen. This choice should also be made based on the knowledge of the antimicrobial resistance peculiar to a given geographical area. We evaluated the prevalence of antimicrobial-resistant H pylori strains isolated from naive patients and from patients with previous unsuccessful treatments.

METHODS

This study examined 109 H pylori-infected subjects (Group 1) who had never received an eradication treatment and 104 H pylori-infected subjects (Group 2) who had failed one or more eradication treatments. Resistance to amoxicillin (AMO), tetracycline (TET), clarithromycin (CLA), metronidazole (MET) and levofloxacin (LEV) was determined using the epsilometer test. The significance of differences was evaluated by the chi2 test.

RESULTS

The prevalence of antimicrobial resistance was 0% versus 3.1% to AMO, 0% versus 2% to TET, 27% versus 41.3% to MET (p<0.05), 18% versus 45.8% to CLA (p<0.05) and 3% versus 14.6% to LEV (p<0.05) in Group 1 vs Group 2, respectively. In Group 2, there was an increased prevalence of H pylori strains resistant to multiple antimicrobials.

CONCLUSIONS

This study confirms the high prevalence of H pylori strains resistant to CLA and MET, and indicates that unsuccessful treatments significantly increase resistance. Choosing eradication regimens other than standard triple therapy as a first-line therapy should be advisable in areas with high primary antimicrobial resistance prevalence.

Tissue ghrelin level and gastric emptying rate in adult patients with celiac disease

Celiac disease (CD) patients show a number of gastrointestinal motor abnormalities. Ghrelin, a gastric peptide implicated in short-term feeding control and long-term body weight regulation, has been recently considered a key regulator of gastric motility. The aim of this study was to evaluate the gastric emptying rate of solids and the density of ghrelin-immunopositive cells in adult CD patients before and at least 1 year after starting a gluten-free diet. Twenty CD patients (M 8/F 12; mean age 36 years) and 10 controls underwent endoscopy with gastric and duodenal biopsies and 13C-octanoic acid breath test to measure gastric emptying of solids. Celiac disease patients repeated the protocol at least 1 year after starting gluten-free diet. Ghrelin tissue levels were evaluated by immunohistochemistry on gastric mucosa specimens. Gastric emptying time was normal in all control subjects (t(1/2) = 89 +/- 16 min) while it was delayed in CD patients prior to gluten-free diet (t(1/2) = 252 +/- 101 min; P < 0.005). The mean number of ghrelin-positive cells/field (x 400) was 14.4 +/- 2.7 in controls and 25.3 +/- 5.7 in CD patients respectively (P < 0.0001). Gluten withdrawal was effective in normalizing gastric emptying time in all CD patients (97 +/- 14 min; P < 0.0001) and resulted in a significant reduction of the density of ghrelin-immunopositive cells (19.8 +/- 5.4; P < 0.0001). The density of ghrelin-positive cells correlated directly with the degree of duodenal damage (P < 0.001) and inversely with the body mass index of CD patients (P < 0.0001). However, in neither CD patients nor controls, a correlation between tissue ghrelin levels and gastric emptying rate was detected. In conclusion, tissue ghrelin level does not correlate with gastric emptying rate in adult CD patients and in controls.

Sweetened carbonated drinks do not alter upper digestive tract physiology in healthy subjects

Sweetened carbonated beverages are widely consumed, which has fuelled several conflicting opinions about their effects on upper digestive tract functions. We aimed to evaluate the effect of sweetened carbonated drinks, consumed with a standard meal, on gastro-oesophageal reflux, gastric emptying and gallbladder contraction and postmeal sensations in healthy subjects. Thirteen healthy volunteers (seven women, six males; median age 22 years) were tested following the intake of 300 mL sweetened water containing increasing concentrations of carbon dioxide (seven subjects), and of 300 mL sweetened commercial flavoured drink with and without carbon dioxide (six subjects). Gastro-oesophageal reflux, gastric emptying and gallbladder contraction were studied by pH-impedance, octanoic acid breath test and ultrasound respectively. Gastro-oesophageal refluxes were significantly increased 1 h after meal with both water and commercial beverages; only sweetened water without carbon dioxide determined a persistently increasing number of refluxes 2 h postmeal. No differences were found for gastric emptying, gallbladder contraction or postmeal symptoms with any of the beverages tested. This study shows that 300 mL of sweetened carbonated beverage with different levels of carbonation or a commercial soft drink do not modify the physiology of the upper digestive tract.

Interleukin-13 mucosal production in Helicobacter pylori-related gastric diseases

A shift from Th1 (IFN-gamma) towards Th2 (IL-4)-type immune response was found in patients with gastric cancer and dysplasia. Recently, IL-13 has been described as a central mediator of Th2-dominant immune response in different inflammatory diseases.

AIM AND METHODS

to analyse, by Enzyme-Linked-Immuno-SPOT (ELISPOT) assay and immunohistochemistry, the IL-13 production of mononuclear cells obtained from gastric biopsies of 19 H. pylori-negative subjects and 23 H. pylori-positive patients.

RESULTS

By ELISPOT, we did not find any significant variation of the spot range number of IL-13, IL-4 and IFN-gamma secreting cells, irrespective of H. pylori status. After antigenic exposition, the spot range for IL-13, IL-4 and IFN-gamma significantly increased (p<.0001) only in H. pylori-positive patients. A prevalent Th1 (IFN-gamma) immunoresponse was observed in 2/23 cases with active gastritis, while a prevalent Th2 (IL-13 and IL-4) was detected in 5/23 cases all with atrophic chronic gastritis of whom two with intestinal metaplasia. By immunohistochemistry, IL-13, IL-4 and IFN-gamma were detectable in all cases directly related to the inflammatory infiltrate. In the two cases with intestinal metaplasia, IL-13 and IL-4 were localised in both inflammatory and epithelial cells. This immunopattern was confirmed in selected additional 10 cases of H. pylori-positive chronic atrophic gastritis with intestinal metaplasia and 10 cases of intestinal type gastric cancer.

CONCLUSION

These preliminary results suggest that IL-13 could be implicated in the different outcome of H. pylori infection.

Gastric adenomas: relationship between clinicopathological findings, Helicobacter pylori infection, APC mutations and COX-2 expression

Gastric adenomas are rare neoplastic growths characterized by localized polypoid proliferations of dysplastic epithelium that tend to progress to infiltrating adenocarcinoma. Therefore, the identification of molecular markers that could reliably recognize adenomas at risk of progression is advocated in the clinical management. In this study we investigated, in a series of gastric adenoma specimens from an area at high risk of gastric cancer, the relationship between clinicopathological characteristics of adenoma and Helicobacter pylori infection, APC mutational status, and COX-2 and the down-stream enzyme mPGES1 expression. Helicobacter pylori infection, detected in 24%, and 33% by histology and PCR analyses, respectively, did not show any relationship with growth pattern, localization, size, dysplasia grade and presence of synchronous cancer. Pathogenetic mutations of MCR region (codons 1269-1589) of the APC gene were detected only in one case corresponding to a single, small size, low grade, H. pylori-negative adenoma. The expression of COX-2 largely matched that of mPGES(1). Both were overexpressed in 79% of cases showing a relationship with high-grade dysplasia, size >10 mm and presence of a synchronous carcinoma. In conclusion, COX-2 may play a key role in the development and progression of gastric adenoma and could be an attractive target in the management of gastric adenoma at major risk of cancer development.

Gliotoxin is a virulence factor of Aspergillus fumigatus: gliP deletion attenuates virulence in mice immunosuppressed with hydrocortisone

Gliotoxin is an immunosuppressive mycotoxin long suspected to be a potential virulence factor of Aspergillus fumigatus. Recent studies using mutants lacking gliotoxin production, however, suggested that the mycotoxin is not important for pathogenesis of A. fumigatus in neutropenic mice resulting from treatment with cyclophosphomide and hydrocortisone. In this study, we report on the pathobiological role of gliotoxin in two different mouse strains, 129/Sv and BALB/c, that were immunosuppressed by hydrocortisone alone to avoid neutropenia. These strains of mice were infected using the isogenic set of a wild type strain (B-5233) and its mutant strain (gliPDelta) and the the glip reconstituted strain (gliP(R)). The gliP gene encodes a nonribosomal peptide synthase that catalyzes the first step in gliotoxin biosynthesis. The gliPDelta strain was significantly less virulent than strain B-5233 or gliP(R) in both mouse models. In vitro assays with culture filtrates (CFs) of B-5233, gliPDelta, and gliP(R) strains showed the following: (i) deletion of gliP abrogated gliotoxin production, as determined by high-performance liquid chromatography analysis; (ii) unlike the CFs from strains B-5233 and gliP(R), gliPDelta CFs failed to induce proapoptotic processes in EL4 thymoma cells, as tested by Bak conformational change, mitochondrial-membrane potential disruption, superoxide production, caspase 3 activation, and phosphatidylserine translocation. Furthermore, superoxide production in human neutrophils was strongly inhibited by CFs from strain B-5233 and the gliP(R) strain, but not the gliPDelta strain. Our study confirms that gliotoxin is an important virulence determinant of A. fumigatus and that the type of immunosuppression regimen used is important to reveal the pathogenic potential of gliotoxin.

TUP1 disruption in Cryptococcus neoformans uncovers a peptide-mediated density-dependent growth phenomenon that mimics quorum sensing

Cryptococcus neoformans is a pathogenic yeast that causes life-threatening meningoencephalitis and grows well on mycological media regardless of inoculum size. Interestingly, a deletion of the global repressor TUP1 in C. neoformans uncovered a density-dependent growth phenotype reminiscent of the quorum-sensing phenomenon. An inoculum size of lower than 10(3) cells of the tup1Delta strain failed to form colonies on agar media while inocula of 10(5)-10(6) cells per plate formed a lawn. This phenotype, expressed as the inability to grow at low cell densities, was rescued by the culture filtrate from a high cell density tup1Delta culture and the active molecule in this culture filtrate was identified to be an oligopeptide composed of 11 amino acids. Activity assays, using a synthetic version of the peptide with strains harbouring a deletion of the corresponding gene, proved that the oligopeptide functioned as an autoregulatory molecule responsible for the density-dependent phenotype. Although a density-dependent growth phenotype has been reported in several species of Ascomycetes, no peptide has been reported to function as an autoregulator in the Kingdom Fungi. The identification of an 11-mer peptide as an autoregulatory molecule in C. neoformans suggests that a diverse mechanism of cell-to-cell communication exists in the Kingdom Fungi.

Gastrokine 1 expression in patients with and without Helicobacter pylori infection

BACKGROUND

To understand the molecular changes underlying Helicobacter pylori-related gastric diseases is mandatory to prevent gastric cancer. Proteomic technology is providing a rapid expansion of the basic knowledge, particularly in the discovery of new biomarkers involved in the tumourigenesis.

AIM

To characterise changes in protein expression level of the gastric mucosa in H. pylori-infected patients.

METHODS

The population enrolled comprised 41 dyspeptic patients. Proteins extracted from gastric mucosal specimens were analysed by 2-dimensional electrophoresis, sequenced by MALDI-TOF and identified by Edman's degradation.

RESULTS

Twenty-one out of 41 patients had H. pylori infection of whom 17 had anti-CagA IgG antibodies. Several proteins were identified, of which Rho guanosine diphosphatase dissociation inhibitor alpha and heat shock protein 27 increased and glutathione transferase and antrum mucosa protein-18 decreased in H. pylori-positive in respect to H. pylori-negative patients. Interestingly, antrum mucosa protein-18, currently referred as gastrokine-1, showed two isoforms differing in the first N-terminal amino acid residue. Both gastrokine-1 isoforms were observed in the H. pylori-negative group whereas a lower expression or even absence of the gastrokine-1 basic isoform was found in a subgroup (7/21) of H. pylori-positive patients with moderate-severe gastritis.

CONCLUSION

Our study demonstrated the presence of gastrokine-1 isoforms of which the basic isoform was reduced in a subset of patients with H. pylori infection.

Heavy metals in coastal water systems. A case study from the northwestern Gulf of Thailand

A geochemical survey of the northwestern part of the Thailand Gulf (Inner Gulf) was carried out in order to define concentrations and distribution patterns of selected heavy metals (V, Cr, Co, Ni, Cu, Zn, and U) in the coastal system and estuarine area of the Mae Klong river. The results indicate the presence of two different sources of heavy metals in the studied environment and allowed us to identify a lithogenic component that significantly influences the composition of coastal waters and suspended particulate matter (SPM). Comparison of the normalized heavy metals concentrations both in the studied samples and in those reported for the Sn-W ores present in the surrounding areas suggests an important anthropogenic contribution to the chemistry of the seafloor sediments. Vanadium and nickel enrichment factors (EF) calculated for coastal waters indicate that contamination by hydrocarbons discharge took place in the investigated area.

Diagnostic accuracy of the serum profile of gastric mucosa in relation to histological and morphometric diagnosis of atrophy

BACKGROUND

Histology is the gold standard for diagnosis of atrophy but is hampered by observer variation. A reliable method to overcome this issue is morphometric analysis of gastric mucosa. Serum pepsinogens and gastrin have been proposed in the diagnostic work-up of gastric atrophy although diagnostic accuracy of these tests is considered unsatisfactory.

AIM

To evaluate the diagnostic accuracy of gastric serum profile in relation both to morphological and morphometric diagnosis of gastric atrophy.

METHODS

Ninety-four dyspeptic out-patients underwent upper endoscopy and evaluation of serum levels of PGI, PGII and 17-gastrin. Diagnostic accuracy of gastric serum profile was tested by receiver operating characteristic curves and by evaluation of sensitivity and specificity in relation to both histology and morphometric analyses.

RESULTS

As far as concern to histological evaluation, only PGI/PGII ratio showed an acceptable diagnostic accuracy in discrimination of gastric atrophy, while, when morphometric analysis was considered as reference, both serum PGI level and PGI/PGII ratio showed an excellent performance. However, both PGI and PGI/PGII ratio showed low sensitivity and high specificity.

CONCLUSIONS

Serological gastric profile corresponds better with the morphometric diagnosis of atrophy, even if, because of the low sensitivity, today this could only be used as screening test of chronic atrophic gastritis.

Nutritional state and energy balance in cirrhotic patients with or without hypermetabolism. Multicentre prospective study by the 'Nutritional Problems in Gastroenterology' Section of the Italian Society of Gastroenterology (SIGE)

BACKGROUND AND AIMS

A total of 334 stable, compensated cirrhotic patients admitted to 10 Italian Gastroenterology Units were included in a prospective study to evaluate nutritional state and energy balance in liver cirrhosis.

MATERIALS AND METHODS

Nutritional state and calorie intake were examined in the total population, while adequacy of calorie intake versus measured total energy expenditure was evaluated in a comparable subpopulation and in 40 matched controls, by computing the energy balance.

RESULTS

Our data demonstrated that: (i) malnutrition was present in 25% of the total patients and significantly correlated with the Child's group (A=16%; B=25%; C=44%); (ii) the type of malnutrition is influenced by mBEE: normometabolic patients exhibit a significant (p<0.005) reduction of mid-arm fat area while both hypermetabolic and hypometabolic patients show a significant (p<0.005) decline in kg of free fat mass; (iii) normometabolic and hypometabolic patients have a negative energy balance, due to a high level of physical activity (127+/-14 kJ) in the first group and a reduced energy intake/kg body weight (102+/-12 kJ) in the second; (iv) hypermetabolic patients have a positive energy balance due to decreased daily physical activity/kg body weight (108+/-28 kJ); (v) malnourished and normometabolic patients eat a significantly (p<0.05) reduced percentage of protein whereas malnourished and hypermetabolic patients eat a significantly increased percentage of fat (p<0.05).

CONCLUSION

Although multivariate regression analysis confirms that the Child-Pugh's score is a better independent predictor of malnutrition, the measure of REE, TEE, calorie intake and energy balance need to be routinely performed in cirrhotic patients, in order to recognise hypermetabolic and hypometabolic patients (approximately 30%) in whom the nutritional and metabolic parameters are indispensable as a basis for designing and prescribing personalised nutritional strategies that can treat muscle malnutrition and thus improve the morbidity and mortality rates.

Twice-daily standard dose of omeprazole achieves the necessary level of acid inhibition for Helicobacter pylori eradication. A randomized controlled trial using standard and double doses of omeprazole in triple therapy

Antibiotic resistances and level of acid inhibition may affect the outcome of eradicating regimens for H. pylori. To evaluate the impact of different degrees of acid inhibition on the efficacy of triple treatment, we treated 323 patients with H. pylori infection with clarithromycin and tinidazole plus omeprazole, either 20 mg bid or 40 mg bid. Gastric biopsies and antimicrobial susceptibility testing were performed. Eradication was evaluated by means of breath test. Eradication rates were (intention to treat and per protocol) 83.3 and 84.3% in patients receiving 40 mg omeprazole and 81.9 and 84.1% in those receiving 80 mg omeprazole. Culture was successful in 218 patients (68.7%). Resistance to clarithromycin and metronidazole were found in 13.7 and 20.6%, respectively. Eighteen further patients (8.2%) presented double resistance. Resistance was comparable across the two groups. In resistant patients the eradication rate was significantly lower (66.6% [95% CI, 56-76%], vs 86% [95% CI, 78-91%]; P = 0.001). Antibiotic resistance (OR, 2.73; 95% CI, 1.4-5.3) and smoking (OR, 2.68; 95% CI, 1.4-5.2) were independent predictors of eradication failure. Omeprazole, 20 mg bid, achieves the optimal acid inhibition in H. pylori eradication. Increasing antisecretory activity does not significantly enhance cure rates.

Review article: helicobacter pylori and molecular events in precancerous gastric lesions

Gastric cancer can be divided into intestinal type and diffuse type that differ substantially in epidemiology and pathogenesis. The most important aetiological factor associated both with intestinal and diffuse gastric cancer, is Helicobacter pylori. Exposure of gastric epithelial cells to H. pylori results in an inflammatory reaction with the production of reactive oxygen species and nitric oxide that, in turn, deaminates DNA causing mutations. The complex interplay between H. pylori strain, inflammation and host characteristics may directly promote diffuse type gastric cancer or induce a cascade of morphological events, i.e. atrophy, intestinal metaplasia and dysplasia, finally leading to intestinal type gastric cancer. Two mechanisms, genetic and epigenetic have been held to play a role in the molecular alterations underlying gastric carcinogenesis. The former, comprising changes in the DNA sequence, is irreversible; the latter, involving DNA methylation, is potentially reversible by eliminating the triggering agents. If H. pylori is eradicated before development of stable mutations, the risk of gastric cancer will likely be prevented. Thus, eradication of H. pylori might immediately reduce the risk of diffuse type gastric cancer, whereas prevention of intestinal type gastric cancer may be less effective if patients are treated later in the evolution of the carcinogenic process.

Is there a link between environmental factors and a genetic predisposition to cancer? A lesson from a familial cluster of gastric cancers

To determine the prevalence of gastric precancerous lesions and mucosal genetic alterations in relatives of a cluster of familial gastric cancer (FGC), we studied a kindred spanning two generations. The founder, daughter and niece underwent surgery for gastric cancer (GC); a son and other two daughters of the founder, presented with chronic dyspepsia. In all subjects, gastric mucosa samples were analysed for pathological features, Helicobacter pylori infection, microsatellite (MIN) and chromosomal (CIN) instability. The overexpression of mp53 and c-myc, and cytoplasmic beta-catenin delocalisation were found in the 2 younger cancer patients. All GC and gastritis patients had normal E-cadherin expression and were MIN-negative. Aneuploidy characterised all GC cases, and mixed euploid and aneuploid cell populations were present in the gastric biopsies from two of three 'at-risk' relatives. These two subjects, one of whom had severe active gastritis, and gastric mp53 and c-myc expression, were CagA-positive H. pylori-infected. DNA aneuploidy, p53 and c-myc expression disappeared after H. pylori eradication. In this FGC cluster, genetic abnormalities were found in first-degree relatives (3 patients) only in presence of H. pylori infection (2 cases H. pylori-positive versus 1 case H. pylori-negative) supporting the hypothesis that, besides the influence of a genetic profile, FGC may be, at least partly, mediated by intrafamilial clustering of H. pylori infection.

Review article: molecular basis of gastric carcinogenesis

Gastric cancer is constituted by two histomorphological entities 'intestinal' and 'diffuse', however lesions with similar morphologies may differ in biological aggressiveness and response to therapy. Two distinct molecular pathways have been identified in gastric carcinogenesis: the microsatellite mutator phenotype and a phenotype associated with chromosomal and intrachromosomal instability. Mounting evidence suggests that microsatellite mutator phenotype alterations and expression of the products of cancer-related genes are early markers of cell transformation, and may serve to identify the gastric carcinoma histotypes. The lack of a clear genetic basis, lends weight to the notion that gastric cancer is not a monomorphic entity but may be affected by environmental factors. Helicobacter pylori is the most important environmental risk factor associated with sporadic gastric cancer. Exposure of gastric epithelial cells to bacterium results in the generation of reactive oxygen species and inducible nitric oxide synthase that in turn may cause genetic alterations leading to cancer in a subset of subjects. Thus, gastric cancer may be considered the result of an interplay between host genetic profile and environmental toxic agents. The new technologies of molecular analysis will help to establish an individual's risk of developing gastric cancer and will lead to novel biological therapeutic strategies.

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.

Acid exposure and altered acid clearance in GERD patients treated for Helicobacter pylori infection

BACKGROUND

After the eradication of Helicobacter pylori, an increased incidence of gastroesophageal reflux disease and acid gastric secretion have been reported.

AIM

To evaluate the effect of Helicobacter pylori-eradication on proximal and distal gastroesophageal reflux and acid clearance in patients with gastroesophageal reflux disease.

PATIENTS AND METHODS

Sixty-eight gastroesophageal reflux disease patients (age range 18-61 years) were studied by upper endoscopy. All underwent esophageal manometry and dual probe 24-h pH-metry.

RESULTS

Percent of time at pH<4 was significantly increased in the proximal esophagus of Helicobacter pylori-eradicated patients compared to Helicobacter pylori-negative (2.4+/-0.5 vs. 1.0+/-0.2; p<0.01); no differences were found in the distal esophagus (14.0+/-3.7 vs. 9.0+/-1.4%, NS). The total number of reflux episodes was significantly higher in the proximal oesophagus of Helicobacter pylori-eradicated patients (37+/-3 vs. 22+/-3, p<0.05). In the distal esophagus, acid clearance was significantly longer, both during total time (1.4+/-0.2 vs. 0.8+/-0.7 min, p<0.01), and in the supine period (8.5+/-2.7 vs. 2.7+/-0.4 min, p<0.05). No differences were reported in the manometric parameters of the two groups of patients.

CONCLUSION

In patients with gastroesophageal reflux disease, Helicobacter pylori eradication is associated with increased acid exposure of the proximal esophagus and delayed distal acid clearance.

An immunodominant DQ8 restricted gliadin peptide activates small intestinal immune response in in vitro cultured mucosa from HLA-DQ8 positive but not HLA-DQ8 negative coeliac patients

BACKGROUND

Studies on intestinal T cell clones from the mucosa of patients with coeliac disease have led to the identification of immunogenic gliadin epitopes. One is HLA-DQ8 restricted, its recognition by T cells being increased by introduction of negatively charged residues operated by tissue transglutaminase.

AIM

To test HLA-DQ8 restricted epitope in both native (QYPSGQGSFQPSQQNPQA) and deamidated (QYPSGEGSFQPSQENPQA) forms in an organ culture system of treated coeliac mucosa from HLA-DQ8 positive and HLA-DQ8 negative patients.

PATIENTS AND METHODS

Jejunal biopsies obtained from 10 patients with coeliac disease (six HLA-DQ8 positive and four HLA-DQ8 negative) were cultured in vitro with a peptic-tryptic digest (PT) of gliadin, or with the native (peptide A) or deamidated (peptide B) peptide. Intraepithelial CD3(+) and lamina propria total CD25(+) and CD3(+)CD25(+) cells were counted, lamina propria intercellular adhesion molecule 1 (ICAM-1) expression was evaluated, as well as that of Fas molecules on epithelial cells.

RESULTS

In HLA-DQ8 positive, but not in HLA-DQ8 negative, coeliacs the density of intraepithelial CD3(+) cells, lamina propria total CD25(+), and CD3(+)CD25(+) cells, as well as expression of ICAM-1 and Fas molecules were significantly increased in biopsies cultured with PT, peptide A, or peptide B compared with biopsies cultured in medium alone.

CONCLUSION

These data show that the DQ8 restricted gliadin peptide is immunogenic only in the intestinal mucosa of HLA-DQ8 positive coeliac patients in both native and deamidated forms.

Long-lasting intestinal bleeding in an old patient with multiple mucosal vascular abnormalities and Glanzmann's thrombasthenia: 3-year pharmacological management

A 75-year-old woman with Glanzmann's thrombasthenia was admitted because of persistent melaena. Endoscopic examination showed multiple angiodysplastic lesions, with active bleeding in small and large bowel. Electro-coagulation of some lesions, octreotide, conjugated oestrogens and selective embolization of jejunal vessels did not change transfusion requirements. After 8 month-transfusions, ethinylestradiol + norethisterone in association with octreotide was started, leading to no transfusion over the following 9 months. Bleeding recurred after withdrawing octreotide and substituting ethinylestradiol + norgestrel for the ethinylestradiol + norethisterone combination. Re-introduction of octreotide did not improve bleeding; however, a reduction of transfusion requirement was observed when the ethinylestradiol + norethisterone pill was re-administered. The association of octreotide and of an oestrogen-progesterone combination was helpful in the difficult management of recurrent bleeding in this patient with diffuse gastrointestinal vascular abnormalities and a severe condition predisposing to bleeding.