Gastroenterology and Hepatology from Bed to Bench

Colorectal cancer is one of the most common malignancy in the world and the second cancer-related death, many molecular and genetic aspects of this disease have been cleared as chromosomal instability and the role of some key proteins as WNT/? catenin, trypsin and others. Also recently the role of folate turnover and some neurotransmitters as serotonin were also considered. The scope of this review is to describe some details about new molecular pathways suggested for occurrence or progress of this disease.

Tolerable gluten thresholds in gluten free products have long been debated together with issues of cross contamination of gluten free cereals during the milling process. It is well established that a totally gluten free diet is virtually impossible owing to the presence of traces of gluten. It is estimated that daily consumption of gluten from contaminated gluten free foods is in the range of 5 to 50 mg. We believe evidence is mounting that it may be possible for some coeliac patients to tolerate gluten above the limits considered permissible at threshold levels. Conversely, it seems there is evidence that some patients might have a much lower threshold for gluten. Whatever would be the individual threshold, GFD may be of benefit to any symptomatic patients even those with milder enteropathy like microscopic enteritis.

This evaluation was undertaken to analyse the overall merit of studies for publication in Medical Journals. Peer review, in which peer experts evaluate the value of a manuscript submitted to a professional journal, is regarded as a crucial step in publication. It helps to ensure that published articles describe experiments that focus on important issues and that the research is well designed and executed. By using previous guidelines and literature review, we have developed an assessment tool to evaluate the scientific studies in an effective and systematic order. Using these tools will facilitate comprehensive assessment and will contribute in generating constructive criticisms.

Nanotechnology is the engineering of functional systems at the molecular scale which may exert a revolutionary impact on cancer diagnosis and therapy. Nanotechnology is being applied to cancer in two broad areas: i) the development of nanovectors such as nanoparticles which can be loaded with drugs or imaging agents and then targeted to tumours, and ii) high-throughput nanosensor devices for detecting the biological signatures of cancer. Combined, such technologies could lead to earlier diagnosis and better treatment for cancer patients.

Aim: The aim of the current investigation was to examine the profile of Kras mutations accompanied with MSI (microsattelite instability) status in polyps and colorectal carcinoma tissues in an Iranian population.

Background: Kras mutations in colorectal cancer cause resistance to anti-Epidermal Growth Factor Receptor (EGFR). So it can be considered as a true indicator of EGFR pathway activation status. Kras mutations can be detected in approximately 30% to 40% of all patients with colorectal cancer. The most hot spot of the gene is located in exons 2 and 3.

Patients and methods: In this study we examined exons 2 and 3 Kras gene using polymerase chain reactions and subsequent sequencing of the exons in 95 patients with sporadic colorectal cancer including 48 tumors and 47 polyps. This study was performed using biopsy samples from the patients. We sequenced the Kras gene in a panel of human colorectal tumors and polyps in addition to detecting MSI status using fluorescent technique.

Results: We could detect 6 mutations in tumors including 5 mutations in codon 12 and one mutation in codon 13. Moreover, in polyps 2 mutations were determined in codon 13 and one in codon 12. Microsatellite instability assay revealed the presence of 5 and 6 MSI in tumors and polyps, respectively. Among the MSI mononucleotide markers, NR-21 marker demonstrated the most frequency (60%) in the both groups.

Conclusion: Our findings showed that probably the profile of mutations in tumors is not entirely compatible with the pattern of mutations in polyps .However, just one of the mutations, Gly12Asp, was similar in both groups.

Background: It is widely considered that a regular breakfast provides a number of health benefits; however, there is no general scientific agreement regarding what kind of food should be consumed. Evidence supports the importance of balancing blood glucose levels by low glycaemic index/load (L-GI/L) and increased protein diets, in particular in metabolic disorders, which non-alcoholic fatty liver disease (NAFLD) has a close relation to.  Aim: The purpose of this study is to explore whether the types and quality of breakfast could influence energy levels (blood glucose levels) and propose ideal breakfast models. Method: This study was conducted by using a valid and standard questionnaire at the University of Worcester to evaluate the breakfast and dietary habits and energy levels. The Kruskal-Wallis test was used for statistical analysis. Results: No significant differences were found either between breakfast consumption, energy levels, types of snack and amount of caffeine intake in the morning or between types of breakfast, energy levels, types of snack, and amount of caffeine intake in the morning. However, potential differences in energy levels were found across the groups of breakfast types: GL (p=.057) and protein intake (p=.056). Conclusions: The types and quality of breakfast would be key as regular breakfast consumption alone did not show adequate health benefits. Lower GL foods and higher protein intake at breakfast were found to be associated with higher energy levels. It is therefore recommended that breakfast foods should be low in GL and high in protein. These changes may lead to better health status and prevention of disease, especially metabolic disorders, in the long term.

Aim: The purpose of this study was to describe the occurrence of self report bloating and related factors in patients with irritable bowel syndrome (IBS).

Background: Bloating symptoms are common in patients with IBS and have significant impact on normal daily function.

Patients and methods: This study was a community-based cross-sectional survey that conducted using a valid questionnaire base on Rome III criteria. Univariate analysis was used for investigation about distribution of self reported bloating according to demographic and psychological factors in irritable bowel syndrome patients.

Results: Out of 18180 subjects under study, 198 cases met criteria for the diagnosis of the irritable bowel syndrome according to criteria ROME III and 61.6% reported bloating symptoms. Bloating symptoms were more prevalent among patients with intermittent symptoms and diarrhea than in patients with constipation. Catastrophic events and depression were independent risk factors for bloating.

Conclusion: Findings of this study support the clinical impression regarding the high prevalence of bloating symptoms in patients with irritable bowel syndrome. Further studies are needed to understand the role of physiological and psychological factors and their interaction in development of bloating in irritable bowel syndrome patients.

Aim: The aim of this survey was to compare four DNA extraction methods from Iranian sheep strain E.granulosus isolates.

Background: Cystic echinococcosis (CE) caused by the metacestode of the dog tapeworm Echinococcus spp., is a global zoonotic infection which is economically important and constitutes a major threat to public health in many countries. Strains characterization is essential for the establishment of a preventive and control strategy in every endemic area.

Patients and methods: Forty five infected organs from cattle, sheep and goat were collected from different abattoirs of Iran. All cysts were examined by microscopic observation of protoscoleces. For each cyst, protoscoleces were aspirated and DNA of each cyst was extracted with 4 different methods including tissue Kit extraction, modified Cinnagen extraction kit, Phenol-chloroform (Sambrook1999) and modified Phenol chloroform methods. Efficiency of the DNA was determined by degree of success in PCR amplification.

Results: Cinnagen modified extraction and modified Phenol chloroform methods were equally effective and superior to other methods after DNA electrophoresis and PCR reaction. Inhibition was observed in PCR with DNA isolated from protoscoleces, and a 1/100 dilution was able to alleviate this problem with DNA extracted.

Conclusion: The result of this study show that the quality of extracted DNA using modified Cinnagen extraction kit and modified phenol-chloroform are very high and gave identical results after RCR reaction using 12S rRNA gene. Further evaluation is required for its utilization in other clinical specimens.

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