New inhibitors of Helicobacter pylori urease holoenzyme selected from phage-displayed peptide libraries.

Urease is an important virulence factor for Helicobacter pylori and is critical for bacterial colonization of the human gastric mucosa. Specific inhibition of urease activity has been proposed as a possible strategy to fight this bacteria which infects billions of individual throughout the world and can lead to severe pathological conditions in a limited number of cases. We have selected peptides which specifically bind and inhibit H. pylori urease from libraries of random peptides displayed on filamentous phage in the context of pIII coat protein. Screening of a highly diverse 25-mer combinatorial library and two newly constructed random 6-mer peptide libraries on solid phase H. pylori urease holoenzyme allowed the identification of two peptides, 24-mer TFLPQPRCSALLRYLSEDGVIVPS and 6-mer YDFYWW that can bind and inhibit the activity of urease purified from H. pylori. These two peptides were chemically synthesized and their inhibition constants (Ki) were found to be 47 microM for the 24-mer and 30 microM for the 6-mer peptide. Both peptides specifically inhibited the activity of H. pylori urease but not that of Bacillus pasteurii.

Allergen-specific antibody and cytokine responses, mast cell reactivity and intestinal permeability upon oral challenge of sensitized and tolerized mice.

BACKGROUND: Food allergy has reached an epidemic level in westernized countries and although central mechanisms have been described, the variability associated with genetic diversity underscores the still unresolved complexity of these disorders. OBJECTIVE: To develop models of food allergy and oral tolerance, both strictly induced by the intestinal route, and to compare antigen-specific responses. METHODS: BALB/c mice were mucosally sensitized to ovalbumin (OVA) in the presence of the mucosal adjuvant cholera toxin, or tolerized by intra-gastric administrations of OVA alone. Antibody titres and cytokines were determined by ELISA, and allergic status was determined through several physiologic parameters including decline in temperature, diarrhoea, mast cell degranulation and intestinal permeability. RESULTS: OVA-specific antibodies (IgE, IgGs and IgA in serum and feces) were produced in sensitized mice exclusively. Upon intra-gastric challenge with OVA, sensitized mice developed anaphylactic reactions associated with a decline of temperature, diarrhoea, degranulation of mast cells, which were only moderately recruited in the small intestine, and increased intestinal permeability. Cytokines produced by immune cells from sensitized mice included T-helper type 2 cytokines (IL-5, IL-13), but also IL-10, IFN-gamma and IL-17. In contrast, all markers of allergy were totally absent in tolerized animals, and yet the latter were protected from subsequent sensitization, demonstrating that oral tolerance took place efficiently. CONCLUSION: This work allows for the first time an appropriate comparison between sensitized and tolerized BALB/c mice towards OVA. It highlights important differences from other models of allergy, and thus questions some of the generally accepted notions of allergic reactions, such as the protective role of IFN-gamma, the importance of antigen-specific secretory IgA and the role of mucosal mast cells in intestinal anaphylaxis. In addition, it suggests that IL-17 might be an effector cytokine in food allergy. Finally, it demonstrates that intestinal permeability towards the allergen is increased during challenge.

Cancer mortality in Europe, 2000-2004, and an overview of trends since 1975.

BACKGROUND: To update the pattern of cancer mortality in Europe. Materials and methods: We analysed cancer mortality in 34 European countries during 2000-2004, with an overview of trends in 1975-2004 using data from the World Health Organization. RESULTS: From 1990-1994 to 2000-2004, overall cancer mortality in the European Union declined from 185.2 to 168.0/100 000 (world standard, -9%) in men and from 104.8 to 96.9 (-8%) in women, with larger falls in middle age. Total cancer mortality trends were favourable, though to a variable degree, in all major European countries, including Russia, but not in Romania. The major determinants of these favourable trends were the decline of lung (-16%) and other tobacco-related cancers in men, together with the persistent falls in gastric cancer, and the recent appreciable falls in colorectal cancer. In women, relevant contributions came from the persistent decline in cervical cancer and the recent falls in breast cancer mortality, particularly in northern and western Europe. Favourable trends were also observed for testicular cancer, Hodgkin lymphomas, leukaemias, and other neoplasms amenable to treatment, though the reductions were still appreciably smaller in eastern Europe. CONCLUSION: This updated analysis of cancer mortality in Europe showed a persistent favourable trend over the last years.

Glucagon-like peptide-1 protects beta-cells against apoptosis by increasing the activity of an IGF-2/IGF-1 receptor autocrine loop.

OBJECTIVE: The gluco-incretin hormones glucagon-like peptide (GLP)-1 and gastric inhibitory peptide (GIP) protect beta-cells against cytokine-induced apoptosis. Their action is initiated by binding to specific receptors that activate the cAMP signaling pathway, but the downstream events are not fully elucidated. Here we searched for mechanisms that may underlie this protective effect. RESEARCH DESIGN AND METHODS: We performed comparative transcriptomic analysis of islets from control and GipR(-/-);Glp-1-R(-/-) mice, which have increased sensitivity to cytokine-induced apoptosis. We found that IGF-1 receptor expression was markedly reduced in the mutant islets. Because the IGF-1 receptor signaling pathway is known for its antiapoptotic effect, we explored the relationship between gluco-incretin action, IGF-1 receptor expression and signaling, and apoptosis. RESULTS: We found that GLP-1 robustly stimulated IGF-1 receptor expression and Akt phosphorylation and that increased Akt phosphorylation was dependent on IGF-1 but not insulin receptor expression. We demonstrated that GLP-1-induced Akt phosphorylation required active secretion, indicating the presence of an autocrine activation mechanism; we showed that activation of IGF-1 receptor signaling was dependent on the secretion of IGF-2. We demonstrated, both in MIN6 cell line and primary beta-cells, that reducing IGF-1 receptor or IGF-2 expression or neutralizing secreted IGF-2 suppressed GLP-1-induced protection against apoptosis. CONCLUSIONS: An IGF-2/IGF-1 receptor autocrine loop operates in beta-cells. GLP-1 increases its activity by augmenting IGF-1 receptor expression and by stimulating secretion; this mechanism is required for GLP-1-induced protection against apoptosis. These findings may lead to novel ways of preventing beta-cell loss in the pathogenesis of diabetes.

Evaluation of patients with stroke monitored by home care programs

The purpose of this study was to evaluate the patient with a stroke in home treatment, investigating physical capacity, mental status and anthropometric analysis. This was a cross-sectional study conducted in Fortaleza/CE, from January to April of 2010. Sixty-one individuals monitored by a home care program of three tertiary hospitals were investigated, through interviews and the application of scales. The majority of individuals encountered were female (59%), elderly, bedridden, with a low educational level, a history of other stroke, a high degree of dependence for basic (73.8%) and instrumental (80.3 %) activities of daily living, and a low cognitive level (95.1%). Individuals also presented with tracheostomy, gastric feeding and urinary catheter, difficulty hearing, speaking, chewing, swallowing, and those making daily use of various medications. It was concluded that home care by nurses is an alternative for care of those individuals with a stroke.

Diabetes mellitus and cancer risk in a network of case-control studies.

Diabetes has been associated to the risk of a few cancer sites, though quantification of this association in various populations remains open to discussion. We analyzed the relation between diabetes and the risk of various cancers in an integrated series of case-control studies conducted in Italy and Switzerland between 1991 and 2009. The studies included 1,468 oral and pharyngeal, 505 esophageal, 230 gastric, 2,390 colorectal, 185 liver, 326 pancreatic, 852 laryngeal, 3,034 breast, 607 endometrial, 1,031 ovarian, 1,294 prostate, and 767 renal cell cancer cases and 12,060 hospital controls. The multivariate odds ratios (OR) for subjects with diabetes as compared to those without-adjusted for major identified confounding factors for the cancers considered through logistic regression models-were significantly elevated for cancers of the oral cavity/pharynx (OR = 1.58), esophagus (OR = 2.52), colorectum (OR = 1.23), liver (OR = 3.52), pancreas (OR = 3.32), postmenopausal breast (OR = 1.76), and endometrium (OR = 1.70). For cancers of the oral cavity, esophagus, colorectum, liver, and postmenopausal breast, the excess risk persisted over 10 yr since diagnosis of diabetes. Our data confirm and further quantify the association of diabetes with colorectal, liver, pancreatic, postmenopausal breast, and endometrial cancer and suggest forthe first time that diabetes may also increase the risk of oral/pharyngeal and esophageal cancer. [Table: see text] [Table: see text].

Role and regulation of polyphosphate in leishmania parasites

Le protozoaire unicellulaire Leishmania est l'agent responsable de la leishmaniose, une maladie parasitaire humaine qui se manifeste par des lésions de la peau, se résolvant le plus souvent spontanément, jusqu'à des lésions viscérales fatales. Le parasite est transmis de l'insecte à l'hôte mammifère lors d'un repas sanguin de la mouche des sables et y réside respectivement sous formes extra- et intracellulaires. On estime que cette maladie touche environ 12 millions de personnes dans 98 pays. Etant donné que les médicaments disponibles à ce jour sont faiblement efficaces et/ou hautement toxiques, il est indispensable de consolider les connaissances sur le fonctionnement et la survie du parasite pour pouvoir développer de nouvelles stratégies de traitements et de préventions. Tous les organismes vivants, dont Leishmania, contiennent du polyphopshate (polyP). Cette molécule chargée négativement est constituée de trois jusqu'à plusieurs centaines de résidus de phosphates reliées par des liaisons à haute énergie. Le polyP sert donc de source d'énergie et de réservoir de phosphate; dans certaines espèces, il joue aussi un rôle dans l'adaptation au stress et la virulence de pathogènes. Ceci nous a amené à étudier le rôle du polyP dans le parasite Leishmania. L'enzyme responsable de la synthèse de polyP a été identifié récemment dans la levure : il s'agit de la chaperone de transport vacuolaire 4 (Vtc4). Nous avons identifié un homologue de Vtc4 chez les Trypanosomatidae, et avons donc décidé d'examiner sa fonction dans le métabolisme du polyP chez Leishmania. En éliminant l'expression de Vtc4 chez L. major et L. guyanensis, nous avons pu démontrer qu'il est indispensable pour la production de polyP chez Leishmania. De plus, nous avons constaté que ces parasites possèdent des chaînes de polyP allant de trois jusqu'à environ 300 résidus de phosphate. Le taux de polyP dans la cellule est précisément régulé et varie entre un très haut niveau durant la phase proliférative des promastigotes à un niveau bas en phase stationnaire tardive, alors que l'expression de Vtc4p reste stable. Dans les amastigotes intracellulaires, seulement des petites quantités de polyP et de Vtc4p sont détectées. En outre, l'absence de Vc4p et de polyP n'a pas d'effet significatif sur les infections in vivo de souris, ce qui indique que le polyP n'est pas nécessaire au développement de la leishmaniose. Ceci suggère que Vtc4p n 'est pas une bonne cible pour le développement de nouveaux traitements contre Leishmania. "Néanmoins, la présence du polyP favorise fortement la survie du parasite suite à un choc de température (37°C) et aide ainsi à sa persistance intracellulaire pendant les premiers jours d'infection de macrophages. En résumé, nos résultats indiquent que si le polyP a peu d'importance pendant l'infection et le développement de la leishmaniose chez la souris, il est par contre crucial pour l'adaptation à des situations de stress comme l'augmentation de la température. Le fait que le polyP a été conservé dans tous les organismes durant l'évolution suggère toutefois que cette molécule joue un rôle fondamental. Etant donné que l'absence de polyP n'a pas d'effet sur la survie des amastigotes, il pourrait être plus important dans la forme promastigote infectant la mouche des sables. - The unicellular protozoan parasite Leishmania is the causative agent of the human disease leishmaniasis, which can range from self-healing skin lesions to fatal visceral lesions. The parasite is transmitted from the insect vector to the mammalian host when the sand fly takes its blood meal and exists in an extra- and an intracellular form, respectively. The disease is estimated to affect 12 million people in 98 countries and currently available drug treatments are of relatively low potency and/or high toxicity. Thus, investigating parasite survival mechanisms and parasite adaptation to the two host environments contributes to the general understanding of Leishmania propagation and might therefore help to develop future treatments or preventions. All living cells, including Leishmania, contain a negatively charged polymer of a few up to several hundred phosphate residues. These so-called polyphosphates (polyPs) serve as an energy source and phosphate reservoir. In some organisms, polyP is also involved in adaptation to stresses and virulence of pathogens. Therefore we were interested in investigating the importance of polyP in Leishmania parasites. Recently, an eukaryotic enzyme responsible for polyP synthesis has been identified as the vacuolar transporter chaperone 4 (Vtc4) in yeast. We, and others, found a Vtc4 homologue in trypanosomatids and decided to examine its potential function in polyP metabolism. By generating VTC4 knock-out cell lines in L. major and Vtc4 knock-down cell lines in L. guyanensis, we were able to demonstrate that Vtc4p is responsible for the total amount of cellular polyP. We also observed that Leishmania polyP chain length ranges from a few up to around 300 residues and that its level is tightly regulated. PolyP abundance is highest during the logarithmic proliferating phase of promastigotes and decreases in the stationary phase, while Vtc4 protein expression remains stable during both phases. In the intracellular amastigote form, only low amounts of polyP and Vtc4p were detectable. Furthermore, absence of Vtc4p and polyP did not have a significant effect on in vivo mouse infections, indicating that polyP is not necessary for Leishmania disease progression. This suggests that Vtc4p would be a poor drug target against Leishmania infection. However, presence of the polymer strongly supported parasite survival during heat shock (37°C) and thereby promoted intracellular persistence during the first days of macrophage infections. Taken together, we found that polyP has little importance in Leishmania {in vivo) infection but that it plays a crucial role during adaptation to stress, such as heat shock. Given that polyP has been preciously conserved in all organisms during evolution it seems to play a fundamental role. Since absence of polyP does not affect amastigote survival, it might be significant for promastigote existence in the sand fly vector.

Chirurgie bariatrique en 2013: principes, avantages et inconvénients des interventions a disposition [Bariatric surgery in 2013: principles, advantages and disadvantages of the available procedures].

For severe obesity (BMI > 35 kg/m2), bariatric surgery is not only the best, but often the only means of obtaining sufficient and durable weight loss. This article aims to review the available bariatric procedures. Gastric bypass remains the reference when it comes to the risk/benefit ratio. Gastric banding is declining rapidly due to the high prevalence of long-term complications. Primary malabsorptive procedures remain largely unpopular because of their potential nutritional complications. Sleeve gastrectomy, although it is not reversible as it includes a significant gastric resection, increases currently in popularity because of its apparent simplicity and the fact that early results regarding weight loss mimic those obtained with gastric bypass.

Non steroidal anti-inflammatory drugs and COX-2 inhibitors as anti-cancer therapeutics: hypes, hopes and reality.

Non-steroidal anti-inflammatory drugs (NSAIDs) and specific inhibitors of cyclooxygenase (COX)-2, are therapeutic groups widely used for the treatment of pain, inflammation and fever. There is growing experimental and clinical evidence indicating NSAIDs and COX-2 inhibitors also have anti-cancer activity. Epidemiological studies have shown that regular use of Aspirin and other NSAIDs reduces the risk of developing cancer, in particular of the colon. Molecular pathology studies have revealed that COX-2 is expressed by cancer cells and cells of the tumor stroma during tumor progression and in response to chemotherapy or radiotherapy. Experimental studies have demonstrated that COX-2 over expression promotes tumorigenesis, and that NSAIDs and COX-2 inhibitors suppress tumorigenesis and tumor progression. Clinical trials have shown that NSAIDs and COX-2 inhibitors suppress colon polyp formation and malignant progression in patients with familial adenomatous polyposis (FAP) syndrome. Recent advances in the understanding of the cellular and molecular mechanisms of the anti-cancer effects of NSAIDs and COX-2 inhibitors have demonstrated that these drugs target both tumor cells and the tumor vasculature. The therapeutic benefits of COX-2 inhibitors in the treatment of human cancer in combination with chemotherapy or radiotherapy are currently being tested in clinical trials. In this article we will review recent advances in the understanding of the anti-tumor mechanisms of these drugs and discuss their potential application in clinical oncology.

EORTC-ROG expert opinion: radiotherapy volume and treatment guidelines for neoadjuvant radiation of adenocarcinomas of the gastroesophageal junction and the stomach.

PURPOSE: The Gastro-Intestinal Working Party of the EORTC Radiation Oncology Group (GIWP-ROG) developed guidelines for target volume definition in neoadjuvant radiation of adenocarcinomas of the gastroesophageal junction (GEJ) and the stomach. METHODS AND MATERIALS: Guidelines about the definition of the clinical target volume (CTV) are based on a systematic literature review of the location and frequency of local recurrences and lymph node involvement in adenocarcinomas of the GEJ and the stomach. Therefore, MEDLINE was searched up to August 2008. Guidelines concerning prescription, planning and treatment delivery are based on a consensus between the members of the GIWP-ROG. RESULTS: In order to support a curative resection of GEJ and gastric cancer, an individualized preoperative treatment volume based on tumour location has to include the primary tumour and the draining regional lymph nodes area. Therefore we recommend to use the 2nd English Edition of the Japanese Classification of Gastric Carcinoma of the Japanese Gastric Cancer Association which developed the concept of assigning tumours of the GEJ and the stomach to anatomically defined sub-sites corresponding respectively to a distinct lymphatic spread pattern. CONCLUSION: The GIWP-ROG defined guidelines for preoperative irradiation of adenocarcinomas of the GEJ and the stomach to reduce variability in the framework of future clinical trials.

Allergen-specific antibody and cytokine responses, mast cell reactivity and intestinal permeability upon oral challenge of sensitized and tolerized mice.

BACKGROUND: Food allergy has reached an epidemic level in westernized countries and although central mechanisms have been described, the variability associated with genetic diversity underscores the still unresolved complexity of these disorders. OBJECTIVE: To develop models of food allergy and oral tolerance, both strictly induced by the intestinal route, and to compare antigen-specific responses. METHODS: BALB/c mice were mucosally sensitized to ovalbumin (OVA) in the presence of the mucosal adjuvant cholera toxin, or tolerized by intra-gastric administrations of OVA alone. Antibody titres and cytokines were determined by ELISA, and allergic status was determined through several physiologic parameters including decline in temperature, diarrhoea, mast cell degranulation and intestinal permeability. RESULTS: OVA-specific antibodies (IgE, IgGs and IgA in serum and feces) were produced in sensitized mice exclusively. Upon intra-gastric challenge with OVA, sensitized mice developed anaphylactic reactions associated with a decline of temperature, diarrhoea, degranulation of mast cells, which were only moderately recruited in the small intestine, and increased intestinal permeability. Cytokines produced by immune cells from sensitized mice included T-helper type 2 cytokines (IL-5, IL-13), but also IL-10, IFN-gamma and IL-17. In contrast, all markers of allergy were totally absent in tolerized animals, and yet the latter were protected from subsequent sensitization, demonstrating that oral tolerance took place efficiently. CONCLUSION: This work allows for the first time an appropriate comparison between sensitized and tolerized BALB/c mice towards OVA. It highlights important differences from other models of allergy, and thus questions some of the generally accepted notions of allergic reactions, such as the protective role of IFN-gamma, the importance of antigen-specific secretory IgA and the role of mucosal mast cells in intestinal anaphylaxis. In addition, it suggests that IL-17 might be an effector cytokine in food allergy. Finally, it demonstrates that intestinal permeability towards the allergen is increased during challenge.

Nilotinib compassionate use in advanced GIST : a retrospective analysis

Introduction: Tyrosine kinase inhibitors (TKI) have considerably improved outcome of patients with advanced GIST and extended overall survival to more than 5 years. Yet, the median progression-free survival is approximately 2 years with first-line imatinib and 24 weeks with second-line sunitinib, which calls for treatment alternatives. Nilotinib is a second-generation TKI with at least similar inhibitory activity as imatinib. A Phase I study has shown that nilotinib monotherapy has clinical activity in GIST. Methods: After failure of all available therapeutic options patients had access to nilotinib on a compassionate use (CU) programm. Nilotinib was started at a dose of 400 mg bid, with dose reduction to 400mg qd allowed in the case of toxicity. 94 pts were approved for nilotinib CU in 10 European countries. We herein present retrospective data of 42 pts from 5 European countries treated in 11 centers. Results: Median age at nilotinib treatment start was 59 years (median; range 24-79 y). 30 of 42 patients were male. Most pts had metastatic disease of gastric origin at initial diagnosis. KIT exon 11 mutations were most frequent. The median number of surgical resections was 1 (range 0-8). All pts had failed both imatinib and sunitinib before nilotinib, and few had also received additional investigational treatments. Nilotinib was well tolerated, and discontinued due to toxicity in 15% only. Median follow-up is 176 days (range 15-876 d). Nilotinib treatment duration is 75 days (median; range 3-727 d). Partial remission with nilotinib treatment was seen in 11% of pts. Median OS was 263 days (Kaplan-Meier). Conclusion: This is the largest series reported assessing efficacy of nilotinib for imatinib- and sunitinib-refractory GIST reported yet. Nilotinib displays significant clinical activity in this heavily pretreated group of pts. These results warrant further investigation of nilotinib in GIST, including its use in first or second-line treatment. Patient and data collection is ongoing, updated results will be presented.

La dyspnée laryngée paroxystique: une manifestation extra-oesophagienne peu connue du reflux gastro-oesophagien [Gastroesophageal reflux: a possible cause of paroxysmal laryngeal dyspnea]

An important number of patients are referred to the ENT specialist because of extraoesophageal manifestations of gastroesophageal reflux. The most alarming symptom is a paroxysmal dyspnea secondary to a laryngospasm. The patients report a laryngeal choking sensation associated to an aphonia. We report three cases of laryngospasm secondary to acid gastric reflux. The diagnosis was made with the clinical history, a laryngeal examination and a 24-hour pH-monitoring enabled us to demonstrate a clear temporal relation between the reflux episodes and the choking episodes. In conclusion, the pharyngo-laryngeal reflux is a possible cause of laryngospasm. In our three patients, a high dose antiacid treatment was efficient to bring a lasting relief of the symptoms.

Polypes et cancers colo-rectaux par sous-localisation: données épidémiologiques genevoises et vaudoises [Colorectal polyps and cancers by sub-site: epidemiologic findings in Geneva and Vaud].

The present study is a comparative analysis of the adenomatous polyps and colorectal cancers, registered during a determined period within the population of the cantons of Geneva and Vaud. The analysis is particularly based on the polyp/cancer ratio by sub-site. Histological type as well as age and sex of the patient are taken into consideration.