662 research outputs found
Farnesyltransferase inhibitors and human malignant pleural mesothelioma: a first-step comparative translational study.
It is known that the potential clinical use of farnesyltransferase
inhibitors (FTI) could be expanded to include
cancers harboring activated receptor tyrosine kinases.
Approximately 70% of malignant pleural mesotheliomas
(MPM) overexpress epidermal growth factor receptors
(EGFR) and a subset express both EGFR and transforming
growth factor A (TGF-A), suggesting an autocrine role for
EGFR in MPM. We checked on MPM cells (10 human cell
lines, 11 primary cultures obtained by human biopsies, and
7 short-term normal mesothelial cell cultures) concerning the
following: (a) the relative overexpression of EGFR (Western
blotting, flow cytometry, immunohistochemistry), (b) the
relative expression of EGFR ligands (EGF, amphiregulin,
TGF-A, ELISA), (c) the relative increase of the activated
form of Ras (Ras-bound GTP) after EGF stimulation (Ras
activation assay), (d) the efficacy of five different FTIs (HDJ2
prenylation, cell cytotoxicity, and apoptosis using ApopTag
and gel ladder). EGFR was overexpressed in MPM cells
compared with normal pleural mesothelial cells in equivalent
levels as in non\u2013small cell lung cancer cells A549.
MPM cells constitutively expressed EGFR ligands; however,
Ras activation was attenuated at high EGF concentrations
(100 ng/mL). Growth of MPM cells was substantially not
affected by treatment with different FTIs (SCH66336, BMS-
214662, R115777, RPR-115135, and Manumycin). Among
these, BMS-214662 was the only one moderately active.
BMS-214662 triggered apoptosis in a small fraction of cells
(not higher than 30%) that was paralleled by a slight
decrease in the levels of TGF-A secreted by treated MPM
cells. Our data highlighted the concept that the same
signaling pathway can be regulated in different ways and
these regulations can differ between different cells of
different origin
Gliadin, zonulin and gut permeability: effects on celiac and non-celiac intestinal mucosa and intestinal cell lines.
OBJECTIVE: Little is known about the interaction of gliadin with intestinal epithelial cells and the mechanism(s) through which gliadin crosses the intestinal epithelial barrier. We investigated whether gliadin has any immediate effect on zonulin release and signaling.
MATERIAL AND METHODS: Both ex vivo human small intestines and intestinal cell monolayers were exposed to gliadin, and zonulin release and changes in paracellular permeability were monitored in the presence and absence of zonulin antagonism. Zonulin binding, cytoskeletal rearrangement, and zonula occludens-1 (ZO-1) redistribution were evaluated by immunofluorescence microscopy. Tight junction occludin and ZO-1 gene expression was evaluated by real-time polymerase chain reaction (PCR).
RESULTS: When exposed to gliadin, zonulin receptor-positive IEC6 and Caco2 cells released zonulin in the cell medium with subsequent zonulin binding to the cell surface, rearrangement of the cell cytoskeleton, loss of occludin-ZO1 protein-protein interaction, and increased monolayer permeability. Pretreatment with the zonulin antagonist FZI/0 blocked these changes without affecting zonulin release. When exposed to luminal gliadin, intestinal biopsies from celiac patients in remission expressed a sustained luminal zonulin release and increase in intestinal permeability that was blocked by FZI/0 pretreatment. Conversely, biopsies from non-celiac patients demonstrated a limited, transient zonulin release which was paralleled by an increase in intestinal permeability that never reached the level of permeability seen in celiac disease (CD) tissues. Chronic gliadin exposure caused down-regulation of both ZO-1 and occludin gene expression.
CONCLUSIONS: Based on our results, we concluded that gliadin activates zonulin signaling irrespective of the genetic expression of autoimmunity, leading to increased intestinal permeability to macromolecules
Non-Celiac Gluten Sensitivity: The New Frontier of Gluten Related Disorders
Non Celiac Gluten sensitivity (NCGS) was originally described in the 1980s and recently a “re-discovered” disorder characterized by intestinal and extra-intestinal symptoms related to the ingestion of gluten-containing food, in subjects that are not affected with either celiac disease (CD) or wheat allergy (WA). Although NCGS frequency is still unclear, epidemiological data have been generated that can help establishing the magnitude of the problem. Clinical studies further defined the identity of NCGS and its implications in human disease. An overlap between the irritable bowel syndrome (IBS) and NCGS has been detected, requiring even more stringent diagnostic criteria. Several studies suggested a relationship between NCGS and neuropsychiatric disorders, particularly autism and schizophrenia. The first case reports of NCGS in children have been described. Lack of biomarkers is still a major limitation of clinical studies, making it difficult to differentiate NCGS from other gluten related disorders. Recent studies raised the possibility that, beside gluten, wheat amylase-trypsin inhibitors and low-fermentable, poorly-absorbed, short-chain carbohydrates can contribute to symptoms (at least those related to IBS) experienced by NCGS patients. In this paper we report the major advances and current trends on NCG
Diagnosis of Non-Celiac Gluten Sensitivity (NCGS)
Non-Celiac Gluten Sensitivity (NCGS) is a syndrome characterized by intestinal
and extra-intestinal symptoms related to the ingestion of gluten-containing
food, in subjects that are not affected by either celiac disease or wheat
allergy. Given the lack of a NCGS biomarker, there is the need for
standardizing the procedure leading to the diagnosis confirmation. In this
paper we report experts’ recommendations on how the diagnostic protocol should
be performed for the confirmation of NCGS. A full diagnostic procedure should
assess the clinical response to the gluten-free diet (GFD) and measure the
effect of a gluten challenge after a period of treatment with the GFD. The
clinical evaluation is performed using a self-administered instrument
incorporating a modified version of the Gastrointestinal Symptom Rating Scale.
The patient identifies one to three main symptoms that are quantitatively
assessed using a Numerical Rating Scale with a score ranging from 1 to 10. The
double-blind placebo-controlled gluten challenge (8 g/day) includes a one-week
challenge followed by a one-week washout of strict GFD and by the crossover to
the second one-week challenge. The vehicle should contain cooked,
homogeneously distributed gluten. At least a variation of 30% of one to three
main symptoms between the gluten and the placebo challenge should be detected
to discriminate a positive from a negative result. The guidelines provided in
this paper will help the clinician to reach a firm and positive diagnosis of
NCGS and facilitate the comparisons of different studies, if adopted
internationally
Scanning Electron Microscopy of the Small Intestine Mucosa in Children with Celiac Disease After Long-Term Dietary Treatment
Jejunal mucosal specimens from twenty children with celiac disease were studied by light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) after one year of dietary treatment. An ultrastructural morphometric study was performed in five patients who had an intestinal permeability (IP) test. Seventeen patients were tested for serum antigliadin antibodies (AGA). In ten children, in whom LM showed partial villous atrophy, SEM and TEM examination confirmed the lesion. In the second group (10 children) with normal morphology at routine LM, SEM showed lesions of variable degree in 70% of cases. The morphological ultrastructural investigation showed good correlation with the immunological and functional data (IP test): ultrastructural damage of the jejunal mucosa after one year of a gluten-free diet was found in patients with positive serum AGA and an abnormal IP test. Furthermore, the morphometric study of the ultrastructural alterations allowed a quantitative, closer correlation between morphological and functional data. Our results suggest: 1) SEM and TEM investigations offer additional and more complete information on celiac patients, over LM alone. 2) The morphometric evaluation of the ultrastructural alterations highlights quantitative and reproducible correlations between morphological and clinical data, not strengthened by the subjective, qualitative study
Marine Cyanobacteria Compounds with Anticancer Properties: Implication of Apoptosis
Marine cyanobacteria have been proved to be an important source of potential anticancer drugs. Although several compounds were found to be cytotoxic to cancer cells in culture, the pathways by which cells are affected are still poorly elucidated. For some compounds, cancer cell death was attributed to an implication of apoptosis through morphological apoptotic features, implication of caspases and proteins of the Bcl-2 family, and other mechanisms such as interference with microtubules dynamics, cell cycle arrest and inhibition of proteases other than caspases
Spectrum of gluten-related disorders: consensus on new nomenclature and classification
A decade ago celiac disease was considered extremely rare outside Europe and, therefore, was almost completely ignored by health care professionals. In only 10 years, key milestones have moved celiac disease from obscurity into the popular spotlight worldwide. Now we are observing another interesting phenomenon that is generating great confusion among health care professionals. The number of individuals embracing a gluten-free diet (GFD) appears much higher than the projected number of celiac disease patients, fueling a global market of gluten-free products approaching $2.5 billion (US) in global sales in 2010. This trend is supported by the notion that, along with celiac disease, other conditions related to the ingestion of gluten have emerged as health care concerns. This review will summarize our current knowledge about the three main forms of gluten reactions: allergic (wheat allergy), autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia) and possibly immune-mediated (gluten sensitivity), and also outline pathogenic, clinical and epidemiological differences and propose new nomenclature and classifications
Early diagnosis of mucopolysaccharidoses in developing countries: A low cost and easy execution approach
none16noopenGabrielli, Orazio; Zampini, Lucia; Monachesi, Chiara; Marchesiello, Rita Lucia; Padella, Lucia; Santoro, Lucia; Volpi, Nicola; Concolino, Daniela; Fiumara, Agata; Rigon, Laura; Mazzoli, Milena; Carnielli, Virgilio Paolo; Giovagnoni, Andrea; Catassi, Carlo; Galeazzi, Tiziana; Coppa, Giovanni ValentinoGabrielli, Orazio; Zampini, Lucia; Monachesi, Chiara; Marchesiello, Rita Lucia; Padella, Lucia; Santoro, Lucia; Volpi, Nicola; Concolino, Daniela; Fiumara, Agata; Rigon, Laura; Mazzoli, Milena; Carnielli, Virgilio Paolo; Giovagnoni, Andrea; Catassi, Carlo; Galeazzi, Tiziana; Coppa, Giovanni Valentin
Recent Progress and Recommendations on Celiac Disease From the Working Group on Prolamin Analysis and Toxicity
Celiac disease (CD) affects a growing number of individuals worldwide. To elucidate the causes for this increase, future multidisciplinary collaboration is key to understanding the interactions between immunoreactive components in gluten-containing cereals and the human gastrointestinal tract and immune system and to devise strategies for CD prevention and treatment beyond the gluten-free diet. During the last meetings, the Working Group on Prolamin Analysis and Toxicity (Prolamin Working Group, PWG) discussed recent progress in the field together with key stakeholders from celiac disease societies, academia, industry and regulatory bodies. Based on the current state of knowledge, this perspective from the PWG members provides recommendations regarding clinical, analytical and legal aspects of CD. The selected key topics that require future multidisciplinary collaborative efforts in the clinical field are to collect robust data on the increasing prevalence of CD, to evaluate what is special about gluten-specific T cells, to study their kinetics and transcriptomics and to put some attention to the identification of the environmental agents that facilitate the breaking of tolerance to gluten. In the field of gluten analysis, the key topics are the precise assessment of gluten immunoreactive components in wheat, rye and barley to understand how these are affected by genetic and environmental factors, the comparison of different methods for compliance monitoring of gluten-free products and the development of improved reference materials for gluten analysis
Federation of international societies of pediatric gastroenterology, hepatology, and nutrition consensus report on celiac disease
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