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151.
Recently we demonstrated that in inflammatory bowel disease (IBD) macrophage-oxidative burst activity is increased and NADPH oxidase mRNA is induced. The herbal phenylethanoid acteoside isolated from Plantago lanceolata L. was shown to exhibit anti-oxidative potential. Using the dextran sulphate sodium (DSS)-induced colitis model, in this study we have assessed whether systemic application of acteoside affects colitis. Colitis was induced by DSS in Balb/c mice. Treatment with acteoside (120, 600 microg/mouse/day) was performed intraperitoneally. The colon lengths were determined. Colonic tissue was scored histologically (max. score 8) by a blinded investigator. T cells isolated from mesenteric lymph nodes (MLN) were stimulated with anti-CD3 antibody in the presence of interleukin (IL)-2 (final concentration 10 U/ml). After incubation for 24 h, IL-1beta, IL-6, IL-12 tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma levels in supernatants were analysed by the beadlyte cytokine detection system. Histological scoring of colonic tissue revealed that application of acteoside was followed by a significantly improved histological score. In acute colitis the histological score was 3.2 with acteoside versus 5.2 with phosphate-buffered saline (PBS) (P < 0.02). In chronic colitis both 120 microg (3.3 versus 5.2) or 600 microg acteoside (3.0 versus 5.2) significantly ameliorated colitis (both P < 0.02). Stimulated MLN from mice with chronic DSS-induced colitis treated with acteoside showed a significant down-regulation of IFN-gamma secretion (195 pg/ml with 600 microg acteoside versus 612 pg/ml with PBS, P < 0.02). Inhibition of oxidative burst activity with acteoside reduced mucosal tissue damage in DSS colitis and could be a therapeutic alternative for IBD treatment. Further studies of this agent are warranted.  相似文献   
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154.

Background

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

Methods

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

Results

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

Conclusion

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.  相似文献   
155.
This study examines the effects of a proton pump inhibitor on a rat model of duodenogastric reflux. Duodenoesophageal reflux was induced in 60 rats by performing a duodenesophagostomy. The study group received daily intraperitoneal injections of a proton pump inhibitor for 6 months and the control group received an equivalent injection of saline. Rats were examined at death for macroscopic tumor, dysplasia, adenocystic changes, papillomatosis, and adenocarcinoma. Five out of 19 rats in the study group and three out of 20 rats in the control group developed dysplastic/adenocarcinomatous changes. Ten of the rats in the study group died before the end of the study, as opposed to one in the control group (this is not statistically significant). There was no difference in the number of cancers that developed in the two groups. However, there was an insignificant trend to earlier appearance of detectable disease in the study group.  相似文献   
156.
BACKGROUND & AIMS: The origin of intestinal metaplasia in short segments of columnar mucosa at the esophagogastric junction has clinical importance but can be difficult to determine at endoscopy. Cytokeratin (CK) 7 and 20 patterns are specific for long-segment Barrett's esophagus; however, their utility in short-segment Barrett's esophagus has not been assessed. METHODS: Endoscopic biopsy specimens from patients with long-segment Barrett's esophagus (n = 49), suspected short-segment Barrett's esophagus (n = 43), and gastric intestinal metaplasia (n = 26) were immunostained for CK7 and CK20. Comprehensive clinical data were obtained, including age, gender, and hiatal hernia and Helicobacter pylori status. RESULTS: A Barrett's CK7/20 pattern was present in 48 (98%) of 49 patients with long-segment Barrett's esophagus, 35 (82%) of 43 with suspected short-segment Barrett's esophagus, and 0 (0%) of 26 patients with gastric intestinal metaplasia. Patients with suspected short-segment Barrett's esophagus with a Barrett's CK7/20 pattern were clinically similar to those with long-segment Barrett's esophagus. In contrast, patients with suspected short-segment Barrett's esophagus with no Barrett's CK7/20 pattern were clinically similar to those with gastric intestinal metaplasia. CONCLUSIONS: A Barrett's CK7/20 pattern identifies a subset of patients with suspected short-segment Barrett's esophagus who have a patient profile similar to that seen in long-segment Barrett's esophagus. A Barrett's CK7/20 pattern is an objective marker of Barrett's mucosa that in conjunction with appropriate clinical and endoscopic data can be used by clinicians to better define patients with short-segment Barrett's esophagus.  相似文献   
157.

Background and objectives

In primary FSGS, calcineurin inhibitors have primarily been studied in patients deemed resistant to glucocorticoid therapy. Few data are available about their use early in the treatment of FSGS. We sought to estimate the association between choice of therapy and ESRD in primary FSGS.

Design, setting, participants, & measurements

We used an inception cohort of patients diagnosed with primary FSGS by kidney biopsy between 1980 and 2012. Factors associated with initiation of therapy were identified using logistic regression. Time–dependent Cox models were performed to compare time to ESRD between different therapies.

Results

In total, 458 patients were studied (173 treated with glucocorticoids alone, 90 treated with calcineurin inhibitors with or without glucocorticoids, 12 treated with other agents, and 183 not treated with immunosuppressives). Tip lesion variant, absence of severe renal dysfunction (eGFR≥30 ml/min per 1.73 m2), and hypoalbuminemia were associated with a higher likelihood of exposure to any immunosuppressive therapy. Only tip lesion was associated with initiation of glucocorticoids alone over calcineurin inhibitors. With adjusted Cox regression, immunosuppressive therapy with glucocorticoids and/or calcineurin inhibitors was associated with better renal survival than no immunosuppression (hazard ratio, 0.49; 95% confidence interval, 0.28 to 0.86). Calcineurin inhibitors with or without glucocorticoids were not significantly associated with a lower likelihood of ESRD compared with glucocorticoids alone (hazard ratio, 0.42; 95% confidence interval, 0.15 to 1.18).

Conclusions

The use of immunosuppressive therapy with calcineurin inhibitors and/or glucocorticoids as part of the early immunosuppressive regimen in primary FSGS was associated with improved renal outcome, but the superiority of calcineurin inhibitors over glucocorticoids alone remained unproven.  相似文献   
158.
We conducted a phase 1/2 trial of high-dose 90Y-ibritumomab tiuxetan in combination with high-dose etoposide (VP-16) 40 to 60 mg/kg (day -4) and cyclophosphamide 100 mg/kg (day -2) followed by autologous stem cell transplantation (ASCT) in 31 patients with CD20+ non-Hodgkin lymphoma (NHL). Patients underwent dosimetry (day -21) with 5 mCi (185 MBq) 111In-ibritumomab tiuxetan following 250 mg/m2 rituximab, followed a week later by 90Y-ibritumomab tiuxetan to deliver a target dose of 1000 cGy to highest normal organ. Bone marrow biopsy was done on day -7 to estimate radiation dose and stem cells were reinfused when the radiation dose was estimated to be less than 5 cGy. The median 90Y-ibritumomab tiuxetan dose was 71.6 mCi (2649.2 MBq; range, 36.6-105 mCi; range, 1354.2-3885 MBq). Histology included follicular lymphoma (n = 12), diffuse large B-cell (n = 14), and mantle cell (n = 5). The median number of prior chemo-therapy treatments was 2. The treatment was well tolerated. The median times to reach an absolute neutrophil count greater than 500/microL and platelet count more than 20,000/microL were 10 days and 12 days, respectively. There were 2 deaths and 5 relapses. At a median follow-up of 22 months, the 2-year estimated overall survival and relapse-free survival rates are 92% and 78%, respectively. We conclude that high-dose 90Y-ibritumomab tiuxetan can be combined safely with high-dose etoposide and cyclophosphamide without an increase in transplant-related toxicity or delayed engraftment.  相似文献   
159.
Atherosclerotic cardiovascular disease results in >19 million deaths annually, and coronary heart disease accounts for the majority of this toll. Despite major advances in treatment of coronary heart disease patients, a large number of victims of the disease who are apparently healthy die suddenly without prior symptoms. Available screening and diagnostic methods are insufficient to identify the victims before the event occurs. The recognition of the role of the vulnerable plaque has opened new avenues of opportunity in the field of cardiovascular medicine. This consensus document concludes the following. (1) Rupture-prone plaques are not the only vulnerable plaques. All types of atherosclerotic plaques with high likelihood of thrombotic complications and rapid progression should be considered as vulnerable plaques. We propose a classification for clinical as well as pathological evaluation of vulnerable plaques. (2) Vulnerable plaques are not the only culprit factors for the development of acute coronary syndromes, myocardial infarction, and sudden cardiac death. Vulnerable blood (prone to thrombosis) and vulnerable myocardium (prone to fatal arrhythmia) play an important role in the outcome. Therefore, the term "vulnerable patient" may be more appropriate and is proposed now for the identification of subjects with high likelihood of developing cardiac events in the near future. (3) A quantitative method for cumulative risk assessment of vulnerable patients needs to be developed that may include variables based on plaque, blood, and myocardial vulnerability. In Part I of this consensus document, we cover the new definition of vulnerable plaque and its relationship with vulnerable patients. Part II of this consensus document will focus on vulnerable blood and vulnerable myocardium and provide an outline of overall risk assessment of vulnerable patients. Parts I and II are meant to provide a general consensus and overviews the new field of vulnerable patient. Recently developed assays (eg, C-reactive protein), imaging techniques (eg, CT and MRI), noninvasive electrophysiological tests (for vulnerable myocardium), and emerging catheters (to localize and characterize vulnerable plaque) in combination with future genomic and proteomic techniques will guide us in the search for vulnerable patients. It will also lead to the development and deployment of new therapies and ultimately to reduce the incidence of acute coronary syndromes and sudden cardiac death. We encourage healthcare policy makers to promote translational research for screening and treatment of vulnerable patients.  相似文献   
160.
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