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71.
72.
Factors predicting progression of gastric intestinal metaplasia: results of a randomised trial on Helicobacter pylori eradication 总被引:13,自引:0,他引:13
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BACKGROUND AND AIMS: Gastric intestinal metaplasia (IM) is generally considered to be a precancerous lesion in the gastric carcinogenesis cascade. This study identified the risk factors associated with progression of IM in a randomised control study. SUBJECTS AND METHODS: A total of 587 Helicobacter pylori infected subjects were randomised to receive a one week course of anti-Helicobacter therapy (omeprazole, amoxicillin, and clarithromycin (OAC)) or placebo. Subjects underwent endoscopy with biopsy at baseline and at five years. Severity of IM was graded according to the updated Sydney classification and progression was defined as worsening of IM scores at five years in either the antrum or corpus, or development of neoplasia. Backward stepwise multiple logistic regression was used to identify independent risk factors associated with IM progression. RESULTS: Of 435 subjects (220 in the OAC and 215 in the placebo group) available for analysis, 10 developed gastric cancer and three had dysplasia. Overall progression of IM was noted in 52.9% of subjects. Univariate analysis showed that persistent H pylori infection, age >45 years, male subjects, alcohol use, and drinking water from a well were significantly associated with IM progression. Duodenal ulcer and OAC treatment were associated with a reduced risk of histological progression. Progression of IM was more frequent in those with more extensive and more severe IM at baseline. With multiple logistic regression, duodenal ulcer (odds ratio (OR) 0.23 (95% confidence interval (CI) 0.09-0.58)) was found to be an independent protective factor against IM progression. Conversely, persistent H pylori infection (OR 2.13 (95% CI 1.41-3.24)), age >45 years (OR 1.92 (95% CI 1.18-3.11)), alcohol use (OR 1.67 (95% CI 1.07-2.62)), and drinking water from a well (OR 1.74 (95% CI 1.13-2.67)) were independent risk factors associated with IM progression. CONCLUSION: Eradication of H pylori is protective against progression of premalignant gastric lesions. 相似文献
73.
Bitnun A Sochett E Dick PT To T Jefferies C Babyn P Forbes J Read S King SM 《The Journal of clinical endocrinology and metabolism》2005,90(1):168-174
Previous pediatric studies have failed to demonstrate a clear association between protease inhibitor (PI) therapy and abnormal glucose homeostasis in HIV-infected children. To define more precisely the impact of PI therapy on glucose homeostasis in this population, we performed the insulin-modified frequent-sampling iv glucose tolerance test on 33 PI-treated and 15 PI-naive HIV-infected children. Other investigations included fasting serum lipids; glucose, insulin, and C-peptide; single-slice abdominal computed tomography; and, in a subset of PI-treated children, an oral glucose tolerance test.There were no differences between the two groups with respect to fasting serum insulin or C-peptide, homeostatic model assessment insulin resistance, or quantitative insulin sensitivity check index. The mean insulin sensitivity index of PI-treated and PI-naive children was 6.93 +/- 6.37 and 10.58 +/- 12.93 x 10(-4)min(-1) [microU/ml](-1), respectively (P = 0.17). The mean disposition index for the two groups was 1840 +/- 1575 and 3708 +/- 3005 x 10(-4)min(-1) (P = 0.013), respectively. After adjusting for potential confounding variables using multiple regression analysis, the insulin sensitivity index and disposition index of PI-treated children were significantly lower than that of PI-naive children (P = 0.01 for both). In PI-treated but not PI-naive children, insulin sensitivity correlated inversely with visceral adipose tissue area (r = -0.43, P = 0.01) and visceral to sc adipose tissue ratio (r = -0.49, P = 0.004). Mildly impaired glucose tolerance was noted in four of 21 PI-treated subjects tested.Our results demonstrate not only that PI therapy reduces insulin sensitivity in HIV-infected children but also that it impairs the beta-cell response to this reduction in insulin sensitivity and, in a subset of children, leads to the development of impaired glucose tolerance. The presence of insulin resistance, dyslipidemia, and the significant correlation of reduced insulin sensitivity with increased visceral adipose tissue content suggest that PI-containing highly active antiretroviral therapy is associated with the emergence of early features of a metabolic syndrome-like phenotype. 相似文献
74.
Jessica Evans Robert Skomro Helen Driver Brian Graham Irvin Mayers Louise McRae Joseph Reisman Corneliu Rusu Teresa To John Fleetham 《Canadian respiratory journal》2014,21(1):e4-e10
BACKGROUND:
An estimated 5.4 million Canadian adults have been diagnosed with sleep apnea or are at high risk of experiencing obstructive sleep apnea (OSA). There are no recent Canadian data regarding access to and predictors of referral for diagnostic testing in these populations.METHODS:
The Sleep Apnea Rapid Response survey sampled 8647 Canadian adults and captured information about risk, testing, diagnosis and treatment of sleep apnea. Predictors of sleep laboratory test referrals were assessed using log-linked binomial regression modelling. Information regarding sleep testing facilities was updated at the provincial and regional levels.RESULTS:
Approximately 76.8% (95% CI 70.1% to 83.6%) of adult Canadians with sleep apnea and 5.1% (95% CI 3.4% to 6.7%) of those at high risk for OSA reported being referred to a sleep laboratory. Significant predictors of sleep laboratory referral in the general population were male sex, middle age, overweight or obese, a chronic condition, having a regular medical doctor and reporting symptoms of sleep apnea. Region of residence was also a predictor of reported sleep laboratory referral, with individuals from Ontario being more likely to report being referred to a sleep laboratory versus individuals from other regions.CONCLUSION:
Individuals reporting risk factors and symptoms associated with OSA were more likely to report a sleep laboratory testing referral compared with those without risk factors or symptoms. However, Canada’s diagnostic sleep laboratory testing capacity varies across regions and is believed to be inadequate given the number of individuals at high risk for OSA who did not report testing referral. 相似文献75.
Kwan‐Lung Ko Wai‐Pan To Lung‐Yi Mak Wai‐Kay Seto Qin Ning James Fung Ching‐Lung Lai Man‐Fung Yuen 《Journal of viral hepatitis》2020,27(4):397-406
Real‐world studies examining reduction in risk of hepatocellular carcinoma (HCC) in patients receiving antivirals are limited by the small size of the studies, or by data insufficiency and heterogeneity with short follow‐up duration. We aimed to examine the real‐world long‐term outcome of patients receiving entecavir treatment on HCC incidence and HBsAg seroclearance. The incidence of HCC in 1225 entecavir‐treated patients between 2002 and 2015 was compared with the HCC incidence estimated using the REACH‐B, GAG‐HCC and CU‐HCC scores. Standardized incidence ratios (SIR) were calculated. The impact of entecavir treatment on HBsAg seroclearance was also explored. The median follow‐up of the cohort was 6.6 years, with 66 cases of HCC development. Using the REACH‐B model, the reduction of HCC risk was significant from year 6 onwards with SIR of 0.68 (95% CI 0.535‐0.866) at year 10. In subgroup patients without cirrhosis, consistent risk reduction was observed from the fifth year and the SIR reached 0.51 (95% CI 0.271‐0.704) by year 10. Benefit in cirrhotic patients was demonstrated when using the GAG‐HCC and CU‐HCC score, with the SIR at year 10 being 0.38 (95% CI 0.259‐0.544) and 0.46 (95% CI 0.314‐0.659), respectively. The cumulative rate of HBsAg seroclearance was 5.2%. HBsAg level at third year of treatment and baseline‐to‐3‐year percentage reduction was predictive of subsequent HBsAg seroclearance. In conclusion, long‐term entecavir therapy was associated with significant reduction in the risk of HCC in the real world. However, HBsAg seroclearance rate remained low. Additional therapy may be considered in patients with adverse predictive factors for subsequent HBsAg seroclearance. 相似文献
76.
Lin Zhang Joseph JY Sung Jun Yu Siew C Ng Sunny H Wong Chi H Cho Simon SM Ng Francis KL Chan William KK Wu 《The Journal of pathology》2014,233(2):103-112
Helicobacter pylori and Epstein–Barr virus (EBV) account for roughly 80% and 10%, respectively, of gastric carcinomas worldwide. Autophagy is an evolutionarily conserved and intricately regulated cellular process that involves the sequestration of cytoplasmic proteins and organelles into double‐membrane autophagosomes that eventually fuse with lysosomes for degradation of the engulfed content. Emerging evidence indicates that xenophagy, a form of selective autophagy, plays a crucial role in the pathogenesis of H. pylori‐ and EBV‐induced gastric cancer. Xenophagy specifically recognizes intracellular H. pylori and EBV and physically targets these pathogens to the autophagosomal–lysosomal pathway for degradation. In this connection, H. pylori or EBV‐induced dysregulation of autophagy may be causally linked to gastric tumourigenesis and therefore can be exploited as therapeutic targets. This review will discuss how H. pylori and EBV infection activate autophagy and how these pathogens evade recognition and degradation by the autophagic pathway. Elucidating the molecular aspects of H. pylori‐ and EBV‐induced autophagy will help us better understand the pathogenesis of gastric cancer and promote the development of autophagy modulators as antimicrobial agents. Published by John Wiley & Sons, Ltd 相似文献
77.
Borges KS Castro-Gamero AM Moreno DA da Silva Silveira V Brassesco MS de Paula Queiroz RG de Oliveira HF Carlotti CG Scrideli CA Tone LG 《Journal of cancer research and clinical oncology》2012,138(3):405-414
Background
Glioblastoma remains one of the most devastating human malignancies, and despite therapeutic advances, there are no drugs that significantly improve the patient survival. Altered expression of the Aurora kinases was found in different malignancies, and their inhibition has been studied in cancer therapy. In this study, we analyzed the expression of Aurora A and Aurora B in glioblastoma samples and also analyzed whether the effects of Aurora kinase inhibition were associated with temozolomide or not on cell lines and primary cultures of glioblastoma. 相似文献78.
79.
Tang KH Ma S Lee TK Chan YP Kwan PS Tong CM Ng IO Man K To KF Lai PB Lo CM Guan XY Chan KW 《Hepatology (Baltimore, Md.)》2012,55(3):807-820
A novel theory in the field of tumor biology postulates that cancer growth is driven by a population of stem-like cells, called tumor-initiating cells (TICs). We previously identified a TIC population derived from hepatocellular carcinoma (HCC) that is characterized by membrane expression of CD133. Here, we describe a novel mechanism by which these cells mediate tumor growth and angiogenesis by systematic comparison of the gene expression profiles between sorted CD133 liver subpopulations through genome-wide microarray analysis. A significantly dysregulated interleukin-8 (IL-8) signaling network was identified in CD133(+) liver TICs obtained from HCC clinical samples and cell lines. IL-8 was found to be overexpressed at both the genomic and proteomic levels in CD133(+) cells isolated from HCC cell lines or clinical samples. Functional studies found enhanced IL-8 secretion in CD133(+) liver TICs to exhibit a greater ability to self-renew, induce tumor angiogenesis, and initiate tumors. In further support of these observations, IL-8 repression in CD133(+) liver TICs by knockdown or neutralizing antibody abolished these effects. Subsequent studies of the IL-8 functional network identified neurotensin (NTS) and CXCL1 to be preferentially expressed in CD133(+) liver TICs. Addition of exogenous NTS resulted in concomitant up-regulation of IL-8 and CXCL1 with simultaneous activation of p-ERK1/2 and RAF-1, both key components of the mitogen-activated protein kinase (MAPK) pathway. Enhanced IL-8 secretion by CD133(+) liver TICs can in turn activate an IL-8-dependent feedback loop that signals through the MAPK pathway. Further, in its role as a liver TIC marker CD133 also plays a functional part in regulating tumorigenesis of liver TICs by way of regulating NTS, IL-8, CXCL1, and MAPK signaling. CONCLUSION: CD133(+) liver TICs promote angiogenesis, tumorigenesis, and self-renewal through NTS-induced activation of the IL-8 signaling cascade. 相似文献
80.
Nobuyuki Horita Masako To Kosuke Araki Kosuke Haruki Yasuo To 《Allergology international》2012,61(4):583-588
Background: Single inhaled corticosteroids and long-acting beta-agonists (ICS/LABA) are clinically effective and safe. However, if local oropharyngeal and laryngeal adverse effects (LOLAE) appear, adherence to the use of ICS is impaired. To minimize the development of adverse effects, it is essential to identify the underlying risk factors.Methods: The study included 481 asthmatic patients who were prescribed ICS/LABA for the first time in their life between January and September of 2010. Patients ranged in age from 14 to 86 years old and consisted of 281 never smokers and 200 smokers. All data were collected retrospectively by respirologists.Results: Seventy-three out of 481 patients suffered from one or more adverse effects, with 54 of these exhibiting LOLAE. Patients with LOLAE (51.4 ± 16.2 yrs) were significantly older than those without LOLAE (43.7 ± 15.9 yrs) (p = 0.0011) and were also prescribed a significantly higher dose of ICS. The pack-years of patients with LOLAE (2.1 ± 4.9) were significantly lowerthan those without LOLAE (6.0 ± 13.0) (p = 0.0087). The type of administered ICS was also significantly associated with a risk of developing LOLAE.Conclusions: Our survey indicated that a greater age, a higher dose of ICS, and the type of ICS were potential risk factors of LOLAE. The identified factors should be considered in a clinical setting in order to prevent the development of LOLAE and provide optimal treatment to patients. 相似文献