bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorescent and quantitative mitochondrial redox imaging of tumor targeted by Octa-RGD probe
Authors: Sha Shuang , Yang Fei , Wang Anle , Jin Honglin , Zhang Zhihong , Lin Qiaoya
Published: April 2016

Integrins, over-expressed in a broad range of cancer diseases, are widely utilized as a tumor biomarker. Metabolism investigation also plays important roles in tumor theranostics. Developing simple integrin-targetting probe and monitoring tumor metabolism will give opportunities to find ways for cancer treatment, however, the investigation of tumor metabolism with integrin receptor based probes has been rarely reported so far. Here, we developed an octavalent fluorescent probe Octa-RGD by convenient genetic method, based on one tetrameric far-red fluorescent protein (fRFP) linked with RGD peptides. We validated its intergin targeting by confocal imaging in vitro. Then we screened a variety of tumor cells, and differentiated their binding affinity based on the fluorescence of the probe via flow cytometry. Among these cells, CNE-2 cells had the highest uptake of the probe, while B16 cells had the lowest, corresponding with their intergin expression levels. Next, the fluorescent and metabolic imaging was performed in HT1080 (intergin postive) tumor, where nicotinamide adenine dinucleotide hydrogen (NADH), flavoprotein (Fp) and fRFP fluorescent signals were collected. The tumor from mice intravenously injected with Octa-RGD probe displayed obviously higher NADH redox ratio NADH/(Fp+NADH) and fRFP signal, than those with fRFP protein. It suggested that integrin targeting may have influence on the target cell metabolism, and further demonstrated Octa-RGD probe facilitated its uptake in the targeted tumor in vivo. This paper developed a useful probe, which can bind integrins specifically and efficiently in tumor cells, and together with tumor metabolic information, it may provide new insight for RGD targeting-based cancer therapeutics.
Finite presentability of generalized Bruck–Reilly ∗-extension of groups
Authors: Oğuz Seda , Karpuz Eylem G.
Published: April 2016

In [Finite presentability of Bruck–Reilly extensions of groups, J. Algebra 242 (2001) 20–30], Araujo and Ruškuc studied finite generation and finite presentability of Bruck–Reilly extension of a group. In this paper, we aim to generalize some results given in that paper to generalized Bruck–Reilly ∗-extension of a group. In this way, we determine necessary and sufficent conditions for generalized Bruck–Reilly ∗-extension of a group, [Formula: see text], to be finitely generated and finitely presented. Let [Formula: see text] be a group, [Formula: see text] be morphisms and [Formula: see text] ([Formula: see text] and [Formula: see text] are the [Formula: see text]- and [Formula: see text]-classes, respectively, contains the identity element [Formula: see text] of [Formula: see text]). We prove that [Formula: see text] is finitely generated if and only if there exists a finite subset [Formula: see text] such that [Formula: see text] is generated by [Formula: see text]. We also prove that [Formula: see text] is finitely presented if and only if [Formula: see text] is presented by [Formula: see text], where [Formula: see text] is a finite set and [Formula: see text] [Formula: see text] for some finite set of relations [Formula: see text].
Simple and mass-produced mechanochemical preparation of graphene nanosheet/polyaniline composite assisted with bifunctional ionic liquid
Authors: Lu Xiangjun , Dou Hui
Published: April 2016

Graphene nanosheet/polyaniline (GNS/PANI) composite was prepared by a simple and mass-produced mechanochemical method, where the functionalized ionic liquid 1-(3-sulfonic acid) propyl-3-methylimidazolium hydrogen sulfate conducts as not only the dispersant of GNS but also the dopant of PANI. The GNS/PANI composite characterized by Fourier transformation infrared spectra, UV–Vis spectra and X-ray diffraction shows that the resulting PANI in composite is in its doped, conductive emeraldine oxidation state. Scanning electron microscope images reveal that the GNS/PANI composite with PANI uniformly coated on the surface of GNS is randomly stacking. Compared with pure PANI, the GNS/PANI composite has higher electrical conductivity, better thermal stability and electrochemical activity due to the presence of GNS.
A study on the effect of surface topography on the actuation performance of stacked-rolled dielectric electro active polymer actuator
Authors: Sait Usha , Muthuswamy Sreekumar
Published: April 2016

Dielectric electro active polymer (DEAP) is a suitable actuator material that finds wide applications in the field of robotics and medical areas. This material is highly controllable, flexible, and capable of developing large strain. The influence of geometrical behavior becomes critical when the material is used as miniaturized actuation devices in robotic applications. The present work focuses on the effect of surface topography on the performance of flat (single sheet) and stacked-rolled DEAP actuators. The non-active areas in the form of elliptical spots that affect the performance of the actuator are identified using scanning electron microscope (SEM) and energy dissipated X-ray (EDX) experiments. Performance of DEAP actuation is critically evaluated, compared, and presented with analytical and experimental results.
Particle swarm optimization with variable neighborhood search for multiobjective flexible job shop scheduling problem
Authors: Huang Song , Tian Na , Ji Zhicheng
Published: April 2016

The simulation on benchmarks is a very simple and efficient method to evaluate the performance of the algorithm for solving flexible job shop scheduling model. Due to the assignment and scheduling decisions, flexible job shop scheduling problem (FJSP) becomes extremely hard to solve for production management. A discrete multi-objective particle swarm optimization (PSO) and simulated annealing (SA) algorithm with variable neighborhood search is developed for FJSP with three criteria: the makespan, the total workload and the critical machine workload. Firstly, a discrete PSO is designed and then SA algorithm performs variable neighborhood search integrating two neighborhoods on public critical block to enhance the search ability. Finally, the selection strategy of the personal-best individual and global-best individual from the external archive is developed in multi-objective optimization. Through the experimental simulation on matlab, the tests on Kacem instances, Brdata instances and BCdata instances show that the modified discrete multi-objective PSO algorithm is a promising and valid method for optimizing FJSP with three criteria.
Corporate Governance Consequences of Accounting Scandals: Evidence from Top Management, CFO and Auditor Turnover
Authors: Agrawal Anup , Cooper Tommy
Published: April 2016

This paper examines the consequences of accounting scandals to top management, top financial officers and outside auditors. We examine a sample of 518 U.S. public companies that announced earnings-decreasing restatements during the 1997–2002 period and an industry-size matched sample of control firms. Using logistic regressions that control for other determinants of management turnover, we find strong evidence of greater turnover of chief executive officers (CEOs), top management and chief financial officers (CFOs) of restating firms compared to the control sample. On average, over the three-year period surrounding the year of restatement announcement, CEOs and CFOs face, respectively, a 14% and 10% greater probability of being replaced in restating firms than in control firms, after controlling for other factors. These represent increases of about 42% and 23%, respectively, compared to the usual turnover probabilities for CEOs and CFOs. The magnitudes of these effects are even larger for restatements that are more serious, have worse effects on stock prices, result in negative restated earnings, are initiated by outside parties, are accompanied by Accounting and Auditing Enforcement Releases (AAERs), or trigger securities class action lawsuits. We find little systematic evidence that auditor turnover is higher in restating firms. Our paper provides evidence of effective functioning of internal governance mechanisms following accounting scandals.
Practical Algorithms for Finding Extremal Sets
Authors: Marinov Martin , Nash Nicholas , Gregg David
Published: April 2016

The minimal sets within a collection of sets are defined as the ones that do not have a proper subset within the collection, and the maximal sets are the ones that do not have a proper superset within the collection. Identifying extremal sets is a fundamental problem with a wide range of applications in SAT solvers, data mining, and social network analysis. In this article, we present two novel improvements of the high-quality extremal set identification algorithm,
AMS-Lex
, described by Bayardo and Panda. The first technique uses memoization to improve the execution time of the single-threaded variant of the AMS-Lex, while our second improvement uses parallel programming methods. In a subset of the presented experiments, our memoized algorithm executes more than 400 times faster than the highly efficient publicly available implementation of AMS-Lex. Moreover, we show that our modified algorithm's speedup is not bounded above by a constant and that it increases as the length of the common prefixes in successive input
itemsets
increases. We provide experimental results using both real-world and synthetic datasets, and show our multithreaded variant algorithm outperforming AMS-Lex by 3 to 6 times. We find that on synthetic input datasets, when executed using 16 CPU cores of a 32-core machine, our multithreaded program executes about as fast as the state-of-the-art parallel GPU-based program using an NVIDIA GTX 580 graphics processing unit.
Computational Methods for Residential Energy Cost Optimization in Smart Grids
Authors: Alam Muhammad Raisul , St-Hilaire Marc , Kunz Thomas
Published: April 2016

A smart power grid transforms the traditional electric grid into a user-centric, intelligent power network. The cost-saving potential of smart homes is an excellent motivating factor to involve users in smart grid operations. To that end, this survey explores the contemporary cost-saving strategies for smart grids from the users’ perspective. The study shows that optimization methods are the most popular cost-saving techniques reported in the literature. These methods are used to plan scheduling and power utilization schemes of household appliances, energy storages, renewables, and other energy generation devices. The survey shows that trading energy among neighborhoods is one of the effective methods for cost optimization. It also identifies the prediction methods that are used to forecast energy price, generation, and consumption profiles, which are required to optimize energy cost in advance. The contributions of this article are threefold. First, it discusses the computational methods reported in the literature with their significance and limitations. Second, it identifies the components and their characteristics that may reduce energy cost. Finally, it proposes a unified cost optimization framework and addresses the challenges that may influence the overall residential energy cost optimization problem in smart grids.
Influence of Acute Mental Stress on the Frequency and Duration of Gastroesophageal Reflux in Normal Volunteers
Authors: Cook IJ , Collins SM
Published: April 2016

Six fasted healthy male volunteers (mean age 21.7 years) were studied. A pH probe was inserted with the tip 5cm proximal to the gastroesophageal junction and recording begun 15 mins after completion of a standard meal. pH was recorded by computerized data logger which sampled every 6s. Subjects were stressed intermittently by a dichotic Listening task in which they attempted to track recorded word Usts heard simultaneously in different ears. Mean frequency and duration of reflux episodes was determined from two 30-min stress and control periods. Alterations in heart rate, systolic and diastolic blood pressure confirmed the effectiveness of the stressor. Mean ( ± SEM) duration of reflux per 30-min stress period ( l . l ±0.53 mins) was not significantly different to mean duration per 30-min control period (l.5 ±0.53 mins). The mean numberof reflux episodes per 30-min stress period (2.3 ± 1.1) did not differ significantly from the mean number of episodes per 30-min control period (2.8± 1.1). T herefore, in normal volunteers acute predictable emotio nal stress does not influence the frequency or duration of postprandial gastroesophageal reflux.
Nutrition and Crohn's Disease: An Overview
Authors: Ó'Moráin C
Published: April 2016

Malnutrition is common in Crohn's disease. Nutrition can be improved in patients with Crohn's disease by total parenteral nutrition (TPN) or enteral nutrition. TPN induces long term remission in over 50% of patients with Crohn's disease. Enteral nutrition is as effective, more economical and less hazardous than TPN. Enteral nutrition can be given as a polymeric or elemental diet. Polymeric diets can be helpful by improving patient nutritional and clinical status. Elemental diets have other advantages in that clinical improvement is not only symptomatic. A controlled trial suggests it to be more effective than polymeric diets in acute Crohn's disease. Four controlled studies have shown elemental diets to be as effective as steroids in acute Crohn's disease. How an elemental diet achieves this result is conjectural, but it is unlikely that its action is solely nutritional, as the patient improves before nutritional parameters improve. Elemental diets contain glutamine and arginine, which have a direct effect on intestinal mucosa and improve immune function. Patients with active Crohn's disease have increased intestinal permeability; treatment with an elemental diet improves the permeability defect.
Hemorrhoids
Authors: Marcon Norman E
Published: April 2016

Hemorrhoids are vascular spaces forming cushions above the anal canal which allow the passage of gas without stool, and cause clinical problems only when they become engorged and prolapse with resulting pain, bleeding, itching or discharge. Hemorrhoids require treatment only if they cause symptoms, and should be treated only as long as symptoms persist. Techniques of treatment including injection therapy, rubber band ligation, infrared coagulation, bipolar probe, heater probe, ultroid and YAG laser are described. At present, rubber banding is the most cost effective therapy. Diet education is essential to prevent recurrence.
Cholangiocarcinoma: A Decade's Experience at a Community-Based University Hospital
Authors: Szilagyi Andrew , Mitmaker Benjamin , Lamoureux Esther
Published: April 2016

Two young patients with cholangiocarcinoma associated with salmonella carriage and ulcerative colitis, respectively, were seen at a community- based university hospital. This experience prompted a review of all cases with this tumour seen in the past decade. Twenty-seven patients were found. Their clinical, laboratory, and histological features, and therapeutic outcome are described. Of the group, only 7.4% were younger than 30 years of age and 14.8% had recognized associated conditions. The most common definable tumour was a well differentiated hilar cholangiocarcinoma. Overall outcome was poor (six months). Survival was similar in patients undergoing palliative stents or surgery. In a small subgroup of surgically treated patients who received either radiotherapy or postoperative drainage, survival seemed to be better.
Outcome of Toxic Megacolon during Pregnancy
Authors: Chartrand-Lefebvre Carl , Heppell Jacques , Potvin Claude , Clermont Richard , Pomp Alfons
Published: April 2016

Two patients with ulcerative colitis required subtotal colectomy and ileostomy for toxic megacolon during pregnancy. Subsequently, a mucosal proctectomy with ileal pouch-anal anastomosis was performed. These two patients who avoided permanent ileostomies were able to carry normal pregnancies and deliver normal infants. These two cases illustrate the clinical features and the favorable outcome of surgical treatment.
Approach to Upper Gastrointestinal Bleeding - When to Treat?
Authors: Rutgeerts P
Published: April 2016

Upper gastrointestinal bleeding from peptic ulcer is a life threatening emergency. Clinical risk factors for fatal outcome have been defined, and endoscopic predictors for rebleeding have been identified. Active ulcer bleeding at endoscopy carries an 80% chance of persistent or recurrent bleeding. A non bleeding visible vessel is associated with a 50% chance of rebleeding. These endoscopic lesions should be treated endoscopically. Failure to obtain definitive hemostasis endoscopically will necessitate emergency surgical treatment.
Immune-Mediated Cytotoxicity in Inflammatory Bowel Disease
Authors: Targan Stephan R , Deem Richard L , Shanahan Fergus
Published: April 2016

Thirty years of research on the role of immune-mediated cytotoxic activity in the tissue injury of inflammatory bowel disease (IBD) has yielded only inconclusive data on the relevance of cytotoxic mechanisms. Two hypotheses have been advanced. One is that the destruction of target cells is mediated by direct recognition of target antigens by cytotoxic cells which in turn triggers lysis. Another hypothesis is that lysis occurs via an indirect bystander mechanism in which cells do not recognize a specific antigen on the target, but upon nonspecific activation release cytokines which are capable of lysing the target. The authors have investigated both hypotheses and studied the role of cytotoxic T cells and cytotoxic rectors released from activated T cells in the destruction of epithelial cells. Elevated levels of cytotoxic T cells were found in peripheral blood lymphocytes of patients with IBD, particularly Crohn's disease. The cytotoxic T cells were contained within the Leu 7+, CD8+ T cell subset and were detected using anti-CD3-triggered lysis. Increased cytotoxic T cell activity was also present within inflamed mucosa of patients with both Crohn's disease and ulcerative colitis. The specific targets of this activity have yet to be determined. Activation of mucosal T cells by antibodies to the T cell receptor (anti-CD3) in organ culture of normal fetal jejunum induces an enteropathy characterized by villous atrophy and crypt cell hyperplasia. This same change is seen near aphthous ulcers in patients with Crohn's disease. Soluble cytokines produced by T cells might be responsible for the mucosa! damage observed in these two models of mucosal injury. The goal of this study was to establish in vitro if cytotoxic cytokines can be released by triggering isolated colonic T cells, and what cytokine interactions are required for killing of colonic epithelial cells. These results demonstrate that human lamina propria lymphocyte T cells, triggered by addition of anti-CD3 and target cells, produce tumour necrosis factor-alpha and interferon-gamma, both of which are required for optimal killing of HT-29. Simultaneous release of these cytokines in the vicinity of epithelial cells during immune responses could play an important role in mucosal damage in IBD. The development of animal models and long term cultures of epithelial cells will allow many advances in research of the role of immune-mediated cytotoxicity in IBD.
Oncogene Mutations in Cancer and Dysplasia Associated with Inflammatory Bowel Disease
Authors: Chen J , Chai C-M , Dalu W , Shen L , Fromowitz F , Compton C , Viola MV
Published: April 2016

Chronic inflammatory bowel disease (IBO) predisposes affected individuals to the development of invasive colon cancer. Increased cancer risk has been seen in ulcerative colitis and Crohn's disease in Western societies as well as in schistosomal colitis in China. In this study it was found that the frequency of the 12th codon of c-Ki-ras, as well as the specific amino acid substitutions, were similar in sporadic colon cancers, cancers associated with ulcerative colitis in the United States, and colon cancers found in patients with schistosomal colitis in Jiangsu province in China. Further, activating mutations of codon 12 of e-Ki-ras were found in high grade dysplastic lesions in chronic ulcerative colitis. The latter finding indicates that some dysplasias are clonal proliferative lesions with genetic characteristics associated with invasive cancer.
Biochemical Features of Alcohol-Induced Liver Disease in Native Versus Non-Native Canadians
Authors: Minuk GY , Thompson W
Published: April 2016

The medical records of 37 native and 40 non-native adult Canadians with alcohol-induced liver disease were reviewed in order to determine whether a biochemical pattern of bile ductular injury (increase in serum alkaline phosphatase levels) was more common and/or severe in native versus non-native Canadians. The results of this retrospective review revealed that serum alkaline phosphatase levels were markedly elevated (at least three tunes the upper limit of normal) in six of 37 (16%) native Canadians as compared to three of 40 (7.5%) non-native Canadians (PÃ0.05). Moreover, the mean peak serum alkaline phosphatase level for native Canadians was significantly higher than for non-natives (262±188 iu/L versus 197±101 iu/L, respectively, mean ± SD, PÃ0.05). Other liver enzyme and function tests were similar in the two groups. The study also revealed chat the mean duration of hospital stay for native Canadians with alcoholic hepatitis is significantly shorter than for nonnatives (8.5±6.0 versus 12.7±1 1.2 days, respectively, PÃ0.05) and the overall duration of hospital stay for patients with alcoholic liver injury has decreased in recent years from 26 days (May 1984-85) to 9.3 days (May 1987-88). The results of this study indicate that alcoholic liver disease in native Canadians is associated with higher serum alkaline phosphatase levels than in non-native Canadians.
Safety Profile of the New 5-ASA Based Compounds
Authors: Sharma Vinod K
Published: April 2016

5-aminosalicylic acid (5-ASA) preparations were anticipated to be and generally are better tolerated than sulphasalazine. Minor side effects such as headache, dizziness, abdominal pain and nausea do occur but are not more frequent than in placebo-treated patients. Approximately 10% of patients thought to be allergic to sulphasalazine are also allergic to 5-ASA. An idiosyncratic reaction with worsening of symptoms can occur. Diarrhea is more common with olsalazine, and it is due to the effect of olsalazine itself on the small bowel. not the 5-ASA component. There are case reports of pancreatitis, pericarditis and bronchospasm, retrosternal chest pain, mild neutropenia, nephrotic syndrome and hair loss associated with 5-ASA treatment. Patients with oligospermia due to sulphasalazine have improved when switched to 5-ASA. 5-ASA enemas can cause local irritation or other effects resulting from enema tip insertion.
Management of Severe Attacks of Ulcerative Colitis with New Technologies
Authors: Campieri M , Gionchetti P , Belluzzi A , Tampieri M , Brignola C , Bertinelli E , Arienti V , Iannone P , Miglioli M , Barbara L
Published: April 2016

Barium enema and colonoscopy are contraindicated in severe attacks of ulcerative colitis because of the possibility of toxic megacolon and perforation. The authors have assessed abdominal ultrasound in 38 patients with severe ulcerative colitis. Ultrasound revealed bowel wall thicknesses ranging from 3.9 to 9.2 mm (mean 7.7) extending the whole length of the colon, to the transverse colon, and to the descending colon, respectively, in 18, 10 and eight patients. The degree of bowel thickening was related to the severity of inflammation based on clinical, sigmoidoscopic and histological evaluation. In two patients, ultrasound showed a thin bowel wall distended without motility, suggesting the diagnosis of toxic megacolon (confirmed radiologically). An excellent correlation (95%) was found between ultrasound and technetium-99 scanning. Ultrasound might be a reasonable first investigation in the assessment of patients with severe ulcerative colitis.
Percutaneous Biliary Drainage with Emphasis on Hilar Lesions
Authors: Gray R
Published: April 2016

The mortality rates of surgery and percutaneous transhepatic biliary drainage (PTHBD) are comparable. Long tenn studies show that delayed complications occur in the majority of cases of PTHBD and survival is not improved compared to surgery. The many recent advances in endoscopic and percutaneous drainage techniques and the recognition that the patient is best served by a noncompetitive multidisciplinary approach will ensure that virtually every patient obtains the most satisfactory drainage possible with a minimum of risk and discomfort. Endoscopic drainage should be the first therapeutic option, with radiologic assistance in the 15 to 25% where endoscopic drainage fails or is incomplete.
Radioimmunoguided Surgery for Colorectal Cancer ‐ An Overview
Authors: Brzezinski Wojciech , Thurston Olin G , Wiens Ernest
Published: April 2016

Many different monoclonal antibodies used experimentally and
clinically are highly tumour‐specific. Radiolahelling of these antibodies has been
successfully accomplished. lmmunoscintigraphy of primary and metastatic cancers
has a reported sensitivity of 59 to 70%. However, in many studies, operative
and histologic confirmation is lacking. Radioimmunoguided surgery is a promising
new adjunctive technique for the surgical treatment of colorectal cancer. Its
reported sensitivity ranges between 70 and 100% and specificity between 66 and
100%. In approximately one‐third of patients wirh colorectal cancer, additional
intraoperative information concerning the presence of subclinical tumours was
gained using radioimmunoguided surgery. This system has the potential to assist
the surgeon in performing complete resection of cancer and decrease the local
recurrence rate. This could be of particular clinical importance for rectosigmoid
tumours where the reported local recurrence rate is as high as 30%. Despite the
advances made, many problems still need to be resolved. The important ones
include: finding an antibody with high tumour specificity and at the same time
rapid clearance from the blood pool and normal tissue ‐ this would avoid the
delay between monoclonal antibody injection and surgery and would make this
approach more easily accepted by the patient; and use of alternative isotopes for
radiolabelling. Radioimmunoguided surgery has the potential to change the way
surgery for colorectal cancer is being performed. It offers the possibility of
improvement in patient survival.
Multicentric Cutaneous Crohn's Disease: A Case Report and Review of Literature
Authors: Prokopetz Robert , Ross J Barrie , Smith Peter , Sidorov Joseph J
Published: April 2016

A patient presented with skin lesions at sites not contiguous with Crohn's disease of the bowel and with specific histological features of Crohn's disease occurring two weeks from the onset of bowel symptoms. Currently a number of nonspecific skin conditions such as erythema nodosum, pyoderma gangrenosum and erythema multiforme are accepted as being the most common skin manifestations of Crohn's disease. It is likely, however, that specific lesions of Crohn's disease in the skin have been underdiagnosed either because of lack of biopsy or misinterpretation of the histology. Twenty-three cases with specific Crohn's disease in the skin have been recorded in the past 25 years, since the condition has been recognized. Sarcoidosis has been a common misdiagnosis. The literature relating to multicentric Crohn's disease is reviewed and attention drawn to its protean and masquerading features. An argument is made for the use of the term 'multicentric' rather than 'metastatic' in relation to cutaneous Crohn's disease.
Severe Bleeding from 'Diversion Pouchitis'
Authors: Heughan Christopher , Barrowman James , Pollett William G
Published: April 2016

A patient suffered severe bleeding from a defunctioned ileal pouch. Although this has not been described before, it may become more prevalent as more patients have ileal pouches to preserve anal function. The possible causes and a possible way of avoiding this catastrophe in the future are discussed.
Animal Studies of Colon Carcinogenesis and Altered Epithelial Cell Differentiation
Authors: Freeman Hugh J
Published: April 2016

Chronic inflammatory bowel disease (IBD) appears to predispose to subsequent colon cancer. Factors that influence the degree of this risk require definition since the reported incidence of malignant change varies widely. Differing environmental factors such as diet may be critical, and several approaches have been used to explore the role of specific variables in colon cancer pathogenesis; one has employed the use of animal models. Naturally occurring models of colon cancer exist including cotton-topped tamarins with colitis. Best studied, however, are animal models of colon cancer induced with specific chemical carcinogens. Cycasin and hydrazine derivatives, eg, 1,2-dimethylhydrazine, are most widely used. After parenteral administration of an active carcinogen, metabolic activation occurs, resulting in colonic adenocarcinomas. Sessile and polypoid neoplasms may be induced, particularly in the distal colon, similar to human colon cancer. Using this model, the effect of differing dietary and therapeutic variables has been explored. Studies with purified single dietary fibres, such as microcrystalline cellulose and hemicellulose, but not pectin, have demonstrated reduced numbers of colonic tumours; these in vivo observations correlate with in vitro effects of fibres on rat luminal and fecal mutagenic activities. Specific therapies used in IBD have also been evaluated - metronidazole, for example, a bacterial mutagen, enhances the development of chemically induced rodent colon cancer. In addition, a significant increase in colonic tumour development occurs after intestinal resection or bypass, two procedures used in the surgical management of IBD. In this setting, surgical sutures, particularly nonabsorbable materials including stainless steel, may play a critical role. Although the extent and duration of disease in patients with chronic IBD may be important in colon cancer pathogenesis, other variables, including diet and treatment, may be critical modulating factors.
Applications and Pitfalls of Endoscopy in Inflammatory Bowel Disease
Authors: Salena BJ , Hunt RH
Published: April 2016

The role of upper gastrointestinal and hepatobiliary endoscopy and colonoscopy in the diagnosis and management of patients with inflammatory bowel disease (IBD) is reviewed. The differentiation of IBD from other forms of colitis, mass lesions in the colon, strictures and polyps, and the management of the patient with dysplasia including clinical strategies for early detection are discussed. The role and value of endoscopic surveillance programs have yet to be defined.
Multiple Hepatic Abscesses Following Yersinia Enterocolitica Septicemia
Authors: Colizza Franco , LePage Serge , LaJoie Jean-François , Duperval Raymond , Marcoux André , Mongeau Jacques , Bergeron Denis
Published: April 2016

Septicemia from Yersinia enterocolitica is unusual. Hepatic involvement
occurring in this clinical setting is a rare complication. A case of a
64‐year‐old man who developed septicemia from Y enterocolitica is reported.
Abdominal ultrasound and computerized axial tomography scan revealed multiple
defects in liver parenchyma compatible with abscesses. After treatment with
intravenous aminoglycosides followed by trimethoprim‐sulfomethoxazole,
recovery was complete. General considerations regarding the manifestations and
pathogenesis of Y enterocolitica are discussed, with a review of the literature.
Overview of Inflammatory Bowel Disease Pathogenesis
Authors: Fiocchi C
Published: April 2016

Inflammatory bowel disease (IBD) represents a difficult and challenging condition for patients, clinicians and basic investigators alike. Its etiology and pathogenesis are still unclear in spite of extensive investigations that have yielded a wealth of clinical. epidemiological, biochemical, bacteriological and immunological data on Crohn 's disease and ulcerative colitis. Although the precise mechanism(s) responsible for the intestinal inflammatory process remain to be defined, enough information has been assembled to hypothesize which components are likely to be important for this probably multifactorial disease. A consistent association between class I or II histocompatibility antigens and either Crohn's disease or ulcerative colitis has yet to be found. Nevertheless, ample epidemiological studies leave no doubt about the high frequency of familial clustering, and it must be determined whether this phenomenon translates a true genetic predisposition or a common environmental exposure, or both. Immune events occurring in the gastrointestinal tract are unquestionably linked to the pathogenesis of IBD, but it is unknown which are primary or secondary in nature. While most immune abnormalities detected in patients with established disease are likely to represent secondary events, these are no less important, as they probably contribute to the perpetuation of gut inflammation and tissue damage. This does not exclude that IBD is due to a primary defect of intestinal immunity, but this may no longer be detectable at the time of clinical manifestations. The answer to the question of wh1ch of the various intestinal immune abnormalities is central to pathogenesis must wait for additional research. Whether immune responses to the luminal flora, antigen processing mechanisms, antibody production, immunoregulation, cytotoxic activity, cytokine and mediator release are defective or disregulated is under intense investigation. It is likely that several of these events are involved, but they may interact in a complex and unpredictable fashion. lt is almost certain that there are various initiating and secondary events, and different immune mechanisms share relatively few common pathways for damaging the intestine, eg, cytokines, arachidonic acid metabolites, and oxidants. Perseverance in the study of these substances is finally yielding promising new approaches to the manipulation of immune and inflammatory responses chat cause bowel destruction. Future drugs may consist of combinations of highly specific inhibitors, antagonists or receptor blockers, that may selectively block one or several steps of the inflammatory cascade which is chronically active in the intestine of affected individuals. Therefore, we may soon face a situation not too dissimilar from what we have recently witnessed for peptic ulcer disease. The specific cause of IBD may still be beyond our comprehension, but a better understanding of its pathogenesis al lows us to put highly effective therapies within reach.
Update in Small Bowel Physiology: Part 1
Authors: Fingerote RJ , Churnratanakul S , Keelan M , Madsen K , Thomson ABR
Published: April 2016

The recent advances in clinically important diseases of the small intestine have been reviewed; however, the basis for many of these clinical advances rests with important observations on alterations in the physiology of the small intestine, as well as mechanistic observations of alterations in small intestinal function in models of human disease. In this review a summary of the past year's literature is presented which will draw attention to the considerable areas of progress in small bowel physiology which will soon be translated into an improved understanding of the pathophysiology of a variety of intestinal disorders.
Antigen Presentation in the Gut
Authors: Doe W , Pavli P
Published: April 2016

The induction of T cell responses requires recognition of antigens in association with class II major histocompatibility complex (MHC) proteins and specialized antigen-presenting cells. Candidate antigen-presenting cells in the gut include dendritic cells, macrophages, B lymphocytes, mucosal epithelial cells and endothelial cells. Dendritic cells isolated from normal human colon are potent inducers of primary immune responses and express high levels of class lI MHC proteins. Lamina propria macrophages display class II MHC proteins, can present antigens to sensitized T cells, may process antigen and release interleukin-l, but suppress antigen presentation by intestinal dendritic cells in a dose-dependent manner. Class II MHC molecules are normally expressed on small intestinal epithelial cells but not on normal colonic epithelial cells. Suppressor T cells and unresponsive T helper cells in the mucosa appear to mediate systemic T cell tolerance of dietary antigens. In the inflamed colon there is infiltration of the lamina propria by large numbers of monocytes which secrete interleukin-1, and the release of interferon-gamma appears to induce class II protein expression on colonic epithelial cells. Colonic epithelial cells from inflamed bowel may preferentially stimulate T helper cells so that local induction of class II MHC molecules on epithelial cells may amplify and localize secondary immune responses at the site of inflamed mucosa. Taken together, the aberrant expression of class II MHC molecules, breaches in epithelial cell integrity (resulting m exposure to luminal antigens including endotoxin and the increased numbers of monocytes found 10 inflamed mucosa suggest that the resulting distortions in antigen presentation contribute to the localization and persistence of the inflammatory lesion in inflammatory bowel disease.
Laser for Colorectal Polyps and Cancer
Authors: Lambert R
Published: April 2016

Laser photodestruction of colorectal polyps and cancer applies almost exclusively to neoplastic lesions. The best results are obtained in exophytic, noninfiltrative, noncircumferential tumours. Neodymium YAG (Nd:YAG) laser is the usual source, and sessions may be repeated at intervals of three to four days during tumour reduction, and at intervals of four to 12 weeks during maintenance therapy. Hemorrhage is a frequent but not severe complication; perforation is the potentially more severe complication. With experience, laser treatment complications decrease to less than 1%. The most common indication of laser phorodestruction concerns destruction of colorectal adenomas. Most indications in malignant adenomas are restricted to the rectum.
Endoscopic Obliteration of Fundal Varices
Authors: Soehendra N , Grimm H , Maydeo A , Nam VC , Eckman B , Bruckner M
Published: April 2016

In cases of portal hypertension, the fundus of the stomach is second to the esophagus as the most likely area for varices, at a frequency of about 10%, in all patients having esophageal varices. It is relatively rare, probably due to the individual vascular anatomy rather than the level of portal pressure. The authors' experience shows that fundal varices appear more frequently with prehepatic block than intrahepatic.
Nasobiliary Drainage
Authors: Kortan Paul
Published: April 2016

Placement of nasobiliary tubes has now become a widely accepted method for therapeutic drainage and instillation of solvents into the biliary tree. The author routinely uses a 300 cm long, 7 or 10 French, specially performed Teflon catheter, which adapts to the anatomy of the duodenum and bile ducts, for the following indications: decompression of obstructed bile duct in acute suppurative cholangitis; prevention of stone impaction after endoscopic sphincterotomy; sequential cholangiography; biliary fistula; instillation of solvents for common bile duct scones; local radiotherapy of biliary malignancies; aspiration of bile for chemical and bacteriological studies; and drainage of pancreatic pseudocysts. Pancreatic or biliary drains should supplement traditional diagnostic and therapeutic modalities in patients with surgical or medical lesions of the pancreas and biliary tree.
Intestinal Motility after Ileal Pouch-Anal Anastomosis
Authors: Heppell Jacques
Published: April 2016

Colectomy, mucosal proctectomy and ileal pouch-anal anastomosis, has become the procedure of choice for carefully selected patients with ulcerative colitis requiring surgery. Pathophysiological studies after the operation have led to a better understanding of the mechanisms of continence and to the development of new technology to study anorectal function. Manometric studies of the anal sphincter, ileal pouch and distal ileum have shown that the operation alters the mechanisms of continence. The maximal tolerable volume of distension of an ileal pouch often approximates that of a normal rectum and yet the functional outcome may differ from a well functioning ileorectal anastomosis. Many other factors influence the result of the operation. The influence of the pattern of motility of the proximal and distal small bowel has been evaluated. The ileal pouch accommodation to distension has been correlated to clinical outcome. Scintigraphic techniques were designed to study the relationship between motility, filling and emptying of the ileal reservoirs. Measures designed to slow intestinal transit, increase absorption and reduce stool output are under investigation.
Endoscopic Colonic Decompression
Authors: Marcon Norman E
Published: April 2016

Colonic pseudo-obscruction, or Ogilvie's syndrome, is characterized by marked distension of the large intestine in the absence of mechanical obstruction. Etiology is unknown. Left untreated, it may lead to perforation with a mortality of 46%. Reversible causes such as electrolyte imbalance, anricholinergic drugs, analgesics, steroids or hypothyro1d1sm should he excluded. Early recognition of pseudo-obstruction with institution of supportive means followed by colonoscopic decompression with rube placement should be successful in all cases.
Efficacy and Tolerance of 5-Aminosalicylic Acid Suppositories in the Treatment of Ulcerative Proctitis: A Review of Two Double-Blind, Placebo Controlled Trials
Authors: Williams CN
Published: April 2016

The efficacy and tolerance of 500 mg 5-aminosalicylic acid (mesalamine) suppositories in the treatment of ulcerative proctitis were assessed in two double-blind, placebo controlled studies of six weeks' duration, involving a total of 173 patients. In trial 1, patients used one 500 mg suppository tid. In trial 2, patients used one 500 mg suppository bid. Physician's global assessment and a disease activity index based upon patient symptoms and sigmoidoscopic appearance were used to assess efficacy. At the endpoint of trial l (tid), there was an 80.4% mean reduction in the disease activity index seen in patients treated with mesalamine compared to a 36.8% mean reduction in the placebo group (P<0.05). Analysis of the physician's global assessment indicated that 84.2% of patients receiving mesalamine were considered to be 'much improved' compared to 41 % of patients on placebo (P<0.01). At the endpoint of trial 2 (tid), there was a 74.7% mean reduction in disease activity index compared to 34.2% in the placebo group (P<0.001). Analysis of the physician's global assessment indicated that 79.2% of the mesalamine group was considered to be 'much improved' compared to 26.2% on placebo (P<0.001). There was no significant difference in efficacy seen in patients treated with 500 mg mesalamine suppositories bid or tid. Mesalamine suppositories are effective and well tolerated in the treatment of ulcerative proctitis.
Endoscopic sphincterotomy - The basics
Authors: Zimmon DS
Published: April 2016

Endoscopic sphincterotomy refers to the incision of the terminal portion of the biliary or pancreatic ducts by a variety of techniques, depending on anatomic circumstances, goals and risks. Alternative methods include percutaneous transhepatic or surgical techniques. The initial Erlangen method - complete sphinccerotomy - carried an unavoidable risk of perforation and hemorrhage. Fractional incision or 'endoscopic papillotomy' - incision of the inferior sphincter - carries no risk of hemorrhage or perforation, done properly. Techniques of papillotomy including 'pull,' 'precut,' stent placement, infundibulotomy, percutaneous cholangiography, and internal spring wire are described, and general electrosurgical principles discussed.
Pancreatic Endosonography: Clinical TNM Staging Compared to Histology
Authors: Tio TL
Published: April 2016

Endosonography has been reported to be effective in the staging of gastrointestinal carcinoma. Pancreatic carcinoma is included in the new (1987) TNM classification. Resectability is abandoned in favour of depth of tumour invasion. In the author's preoperative study, endosonography was accurate for staging of tumour categories, and early stages of disease could be distinguished from advanced carcinomas. The presence or absence of regional lymph nodes can be detected. Tissue diagnosis by biopsy and endosonographyguidcd cytology is now possible. This imaging technique will become the standard procedure for the staging of pancreatic carcinoma.
The Assessment of Evidence Associating Nonsteroidal Anti-Inflammatory Drugs with Complications of Peptic Ulcerations
Authors: Langman MJS
Published: April 2016

A causal relationship is now firmly established between nonsteroidal anti-inflammatory drug (NSAlD) use and the occurrence of peptic ulcer complications. In the United Kingdom, rising NSAID use has been matched by rises in ulcer mortality and perforation rates, particularly in older women. It is not likely, however, that drug use accounts for the entire increase. The reasons why some people develop ulcer complications and others do not are poorly understood. It is plausible to propose that other factors, such as history of ulcer or indigestion, current smoking, and alcohol consumption, might raise this risk; however, supportive evidence is lacking.
Upper Gastrointestinal Tract Crohn's Disease
Authors: Freeman Hugh J
Published: April 2016

Crohn's disease may involve any site within the gastrointestinal tract. Usually pathology is present in the ileum and/or colon, but atypical presentations may occur with apparently 'isolated' involvement of the oropharynx, esophagus or gastroduodenum. If changes typical of Crohn's disease are detected in the upper gastrointestinal tract, then a careful assessment is required involving radiographic, endoscopic and histologic studies to determine if pathology is present in more distal intestine. In addition , microbiologic studies may be important to exclude infectious causes, especially of granulomas. If these studies are negative, prolonged follow-up may be required to establish a diagnosis of Crohn's disease. Although upper gastrointestinal involvement is increasingly recognized as a significant cause of morbidity in Crohn's disease, the treatment options are limited , largely anecdotal and need to be the subject of detailed epidemiologic investigation and clinical trials.
A Planned Long Term Approach to Patient Management
Authors: Binder V
Published: April 2016

On the basis of experience running an outpatient clinic for inflammatory bowel disease (IBO) for more than 25 years we concluded that a long term follow-up regimen offers both therapeutic and scientific advantages. The management program is based on treatment, information and social/ psychological support, factors which are mutually dependent. In Copenhagen County, patients arc offered lifelong affiliation with the IBD clinic, which means annual visits and easy access to treatment during recurrences. With this system, we have been able to conduct epidemiological studies on the incidence and prevalence of IBD in Copenhagen County. A systematic approach to clinical activity assessment is available during the course of the disease for the individual patients. We have found the economic and psychological costs for such a lifelong surveillance program in IBO to be more than outweighed by the benefits to patients and society.