Summary
Surveillance endoscopy of non‐dysplastic Barrett's esophagus (NDBE) that fails to detect intestinal metaplasia (IM), or negative surveillance, is known to occur in clinical practice, although ...the frequency and possible outcomes in a large cohort in clinical practice is not well described. The goals of this study were to define frequency in which negative surveillance occurs and endoscopic outcomes in a screening cohort of short segment NDBE. A retrospective cohort (n = 184) of patients newly diagnosed with short segment NDBE at an outpatient academic tertiary care center between 2003 and 2011 were reviewed. Only those with one or more surveillance endoscopies were included to define a frequency of negative surveillance. Included patients were further assessed if they had two or more surveillance endoscopies and were classified into groups as sampling error or negative IM on consecutive surveillances based on the results of their surveillance endoscopies. The frequency of a negative surveillance endoscopy in all short‐segment NDBE patients was 19.66% (92 endoscopic exams were negative for IM of 468 total surveillance exams). A negative surveillance endoscopy occurred in 40.76% (n = 75) patients. Sampling error occurred in 44.12% and negative IM on consecutive surveillance endoscopies in 55.88% of those with ≥2 surveillance endoscopies and an initially negative surveillance exam. The frequency of negative IM on consecutive surveillances was 19.00% of all patients who had two surveillance endoscopies. When the index diagnostic Barrett's esophagus segment length was <1 cm, 32.14% (18/56) of all patients (with ≥2 surveillance endoscopies) had negative IM on consecutive surveillance endoscopies. Negative surveillance occurs frequently in short‐segment NDBE. When an initial negative surveillance endoscopy occurs, it may be due to either a sampling error or lack of detectable IM on surveillance exam. When a <1 cm segment of NDBE is diagnosed, a significant proportion of patients may go on to have continuously undetected IM on consecutive surveillance endoscopic exams without intervention.
Summary
Current guidelines for endoscopic surveillance of Barrett's esophagus (BE) recommend that patients with newly diagnosed BE undergo confirmatory esophagogastroduodenoscopy (EGD) to exclude the ...presence of dysplasia. The extent to which confirmatory endoscopy alters management and detects missed dysplasia in newly diagnosed BE has not been reported. The frequency with which confirmatory endoscopy changed surveillance management in patients with newly diagnosed BE was assessed. A two center cohort analysis was conducted on patients newly diagnosed with BE. The rate of dysplasia on confirmatory endoscopy for patients who had nondysplastic BE was obtained. Demographic and endoscopic variables were assessed for association with dysplasia detection using Firth logistic regression model. Out of the 146 patients newly diagnosed with BE and initially determined to be without dysplasia, 12 had dysplasia on the confirmatory second EGD (8.2%). Eleven of 12 cases with dysplasia on confirmatory endoscopy had long‐segment BE (LSBE). Among all the LSBE cases in our cohort, 11 had newly diagnosed dysplasia on confirmatory EGD, 29.7% (11/37). The average number of biopsies obtained from the 11 LSBE cases with dysplasia was comparable with the rest of the LSBE cases without dysplasia (6.73 and 5.42, respectively, P‐value 0.205). The rate of dysplasia detection in short‐segment BE (SSBE) was much lower, 0.95% (1 out of 105). There were no cases of high‐grade dysplasia (HGD) or cancer detected in any SSBE case. HGD was detected on confirmatory EGD in two cases, both were LSBE. Segment length was the only statistically significant factor to predict the presence of dysplasia on confirmatory endoscopy (odds ratio 9.158, P. 0.008). Confirmatory EGD in newly diagnosed LSBE had significant rate of dysplasia detection (29.7%) in this cohort. Among patients with SSBE, there was a low rate of dysplasia detection with confirmatory EGD, less than 1% of cases. No additional cases of HGD or esophageal carcinoma in SSBE cases were detected. This suggests that the yield of confirmatory EGD is greater in patients with LSBE.
Evidence-based criteria in the therapeutic choice for sigmoid acute diverticulitis (AD) are lacking. It is necessary to differentiate an acute episode of diverticular disease, not complicated (NCAD) ...and complicated (CAD) because these stages of diverticular disease needs different approach.
In a prospective study on 377 consecutive patients admitted for AD, 265 had NCAD and 112 CAD diagnosed with CT scan. Thirty-six of 265 with NCAD were operated on due to two or more previous episodes of AD. On 188 patients with NCAD followed-up, 35 had further episodes of NCAD and 2 had CAD. On 112 CAD patients, 61 had Hinchey I and were submitted to colonic resection. Twenty-three of 24 patients with Hinchey II were treated with percutaneous drainage. All Hinchey II patients were operated on. All the 13 patients with Hinchey III and IV had emergency surgery.
We had no mortality and respectively 9.8% and 30% morbidity in Hinchey I and II patients. In Hinchey II patients percutaneous drainage was successful in 21 on 23 (91.3%). In 13 Hinchey III and IV patients the mortality rate was 25%. The comparison of CT findings and pathological results showed a sensitivity of 100% and predictive positive value of respectively 94.4, 96.7, 100 and 100% for NCAD, Hinchey I, Hinchey II and Hinchey III-IV.
The therapeutic approach of diverticular disease needs to differentiate among an acute episode, NCAD and CAD. Evidence-based therapeutic choices can be reached only by homogeneous diagnostic criteria obtained by CT scan.
Reactive oxygen species (ROS) produced by inflammatory cells can contribute to tissue destruction. ROS have been implicated in various gastrointestinal abnormalities, including the acid related ...peptic diseases. Although the development of oesophagitis and Barrett's columnar epithelium is associated with prolonged reflux of gastric acid, the exact mechanism by which tissue damage occurs is not known. To discover if ROS are involved in damage to the oesophageal mucosa, this study measured in vitro the mucosal ROS concentrations of biopsied mucosal samples taken from patients with reflux oesophagitis using luminol enhanced chemiluminescence (LECL). Mucosal biopsy specimens were taken from 83 patients: 19 with normal oesophageal mucosa (group I); 20 with macroscopic oesophagitis (group II); 20 with biopsy confirmed Barrett's epithelium without macroscopic oesophagitis (group III); and 24 with Barrett's epithelium with macroscopic oesophagitis (group IV). The mucosa from patients exhibited significantly higher LECL values than the mucosa from controls. But, there were no significant differences between groups II, III, and IV. Addition of the myeloperoxidase inhibitor, azide, or the hydrogen peroxide scavenger, catalase, to the tissue suspension caused a decrease in LECL values of 32% and 45%, respectively, suggesting that neutrophils--although important--are not the only source of mucosal LECL. These data are consistent with the proposal that ROS play an important part in the tissue injury associated with oesophagitis and Barrett's columnar epithelium.
The incidence of adenocarcinoma of the esophagus and gastric cardia is increasing. Many factors are presumed to be associated: symptoms of gastroesophageal reflux disease, tobacco use, alcohol ...consumption, dietary factors, and obesity. A recent large population‐based case‐control study
Nonalcoholic fatty liver disease (NAFLD) includes a wide spectrum of liver injury ranging from simple steatosis to steatohepatitis, fibrosis, and cirrhosis. Whereas simple steatosis has a benign ...clinical course, steatohepatitis is a recognized cause of progressive liver fibrosis and can develop into cirrhosis. NAFLD and nonalcoholic steatohepatitis (NASH) are the two most common chronic liver diseases in United States general population with a prevalence of 20% and 3%, respectively. Hepatic steatosis is frequently associated with obesity, type 2 diabetes, and hyperlipidemia with insulin resistance as a key pathogenic factor. A two‐hit theory best describes the progression from simple steatosis to NASH, fibrosis, or cirrhosis. These two hits consist of the accumulation of excessive hepatic fat primarily owing to insulin resistance, and oxidative stress owing to reactive oxygen species (ROS). Mitochondria are the major cellular source of ROS in cases of NASH. Currently, treatment is focused on modifying risk factors such as obesity, diabetes mellitus, and hyperlipidemia. Antioxidants such as vitamin E, N‐acetylcysteine, betaine, and others may be beneficial in the treatment of NASH.
Cultured rat hepatocytes and human hepatoma HepG2 cells were used to evaluate the hepatoprotective properties of polyphenolic extracts from the edible part of artichoke (AE). The hepatocytes were ...exposed to H2O2generated in situ by glucose oxidase and were treated with either AE, or pure chlorogenic acid (ChA) or with the well known antioxidant, N, N'-diphenyl-p-phenilenediamine (DPPD). Addition of glucose oxidase to the culture medium caused depletion of intracellular glutathione (GSH) content, accumulation of malondialdehyde (MDA) in the cultures, as a lipid peroxidation indicator, and cell death. These results demonstrated that AE protected cells from the oxidative stress caused by glucose oxidase, comparable to DPPD. Furthermore, AE, as well as ChA, prevented the loss of total GSH and the accumulation of MDA. Treatment of HepG2 cells for 24 h with AE reduced cell viability in a dose-dependent manner, however, ChA had no prominent effects on the cell death rate. Similarly, AE rather than ChA induced apoptosis, measured by flow cytometric analysis of annexin and by activation of caspase-3, in HepG2 cells. Our findings indicate that AE had a marked antioxidative potential that protects hepatocytes from an oxidative stress. Furthermore, AE reduced cell viability and had an apoptotic activity on a human liver cancer cell line.
In this article, we analyze the cross-correlation between returns of different stocks to answer the following important questions. The first one is: If there exists collective behavior in a financial ...market, how could we detect it? And the second question is: Is there a particular company among the companies of a market as the leader of the collective behavior? Or is there no specified leadership governing the system similar to some complex systems? We use the method of random matrix theory to answer the mentioned questions. Cross-correlation matrix of index returns of four different markets is analyzed. The participation ratio quantity related to each matrices’ eigenvectors and the eigenvalue spectrum is calculated. We introduce shuffled-matrix created of cross correlation matrix in such a way that the elements of the later one are displaced randomly. Comparing the participation ratio quantities obtained from a correlation matrix of a market and its related shuffled-one, on the bulk distribution region of the eigenvalues, we detect a meaningful deviation between the mentioned quantities indicating the collective behavior of the companies forming the market. By calculating the relative deviation of participation ratios, we obtain a measure to compare the markets according to their collective behavior. Answering the second question, we show there are three groups of companies: The first group having higher impact on the market trend called leaders, the second group is followers and the third one is the companies who have not a considerable role in the trend. The results can be utilized in portfolio construction.
•A method to reveal the collective behavior of stocks in a financial market is proposed.•The markets were ranked based on their stocks’ collective behavior.•The stocks were categorized based on their participation in market’s trend.•The results of categorization could be used for portfolio selection.
Vitamin D deficiency is a problem of considerable magnitude that has reemerged as a major public health issue in the United States and several other developed countries. Vitamin D plays a crucial ...role in calcium homeostasis in the body. Hypovitaminosis D leads to osteomalacia and increased risk of fractures, especially in the elderly. Preliminary research suggests that vitamin D can prevent certain types of cancer and autoimmune diseases. A recent large study has shown the association between severe hypovitaminosis D and persistent, non-specific musculoskeletal pain, further suggesting that patients with no apparent cause of pain should be assessed and possibly treated for vitamin D deficiency.
The aims of the present study were: (1) to determine whether short-term supplementation of beta-carotene (BC) or vitamin E (VE; alpha-tocopherol) would result in their respective accumulation in ...normal colonic mucosa and in adenomatous polyps; (2) to determine whether the intake of BC would interfere with the concentration of VE in these target tissues.
Blood and colonic biopsy samples were taken before and after supplementation.
Eighteen volunteers with colonic adenomatous polyps were enrolled into this study.
The supplementation lasted for 43 days and patients were examined over the whole period. Subjects were randomised into four groups according to the four different supplementations: placebo, natural BC (25 000 IU/day), natural VE (400 IU/day), combination BC/VE.
Initially we were aiming for recruitment of 20 patients in each group, however after 2 y of study (1997-1999), we terminated the study because of slow recruitment and analysed the data. In placebo subjects after supplementation, the plasma concentrations of BC and VE remained unchanged, however only two patients were recruited in this group and therefore we did not include this group in our final analysis. In BC group, the plasma BC concentrations increased significantly (P<0.001), while VE concentrations were unchanged. In VE group, VE concentrations increased (P<0.01) and BC did not change, and in BC/VE group both BC (P<0.001) and VE levels (P<0.01) increased significantly. After supplementation, the tissue concentration of BC in normal colonic mucosa in BC group increased significantly (P<0.01) while the VE concentration did not change. In VE group, the concentration of VE in normal colonic mucosa increased slightly but did not reach statistical significance. However, VE concentration increased significantly (P<0.05) in the polyps of this group. In BC/VE group, in which patients received the combination treatment, the BC concentration of normal colonic mucosa increased (P<0.05) but, surprisingly, the VE concentration decreased significantly (P<0.01). Interestingly in the polyps, although the BC concentration increased (P<0.01), the concentration of VE was reduced moderately but did not reach statistical significance.
Supplementation of BC in doses used in this study may have significantly interfered with the VE concentration in the examined tissue and probably with its metabolic pathway.
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