Am J Prev Med
November 2005
Background: Nearly half of Americans do not meet the Surgeon General's recommendation of > or =30 minutes of physical activity daily. Some transit users may achieve 30 minutes of physical activity daily solely by walking to and from transit. This study estimates the total daily time spent walking to and from transit and the predictors of achieving 30 minutes of physical activity daily by doing so.
View Article and Find Full Text PDFBackground: Non-steroidal anti-inflammatory drugs (NSAIDs) seem to prevent several types of cancer, but could increase the risk of cardiovascular complications. We investigated whether use of NSAIDs was associated with a change in the incidence of oral cancer or overall or cardiovascular mortality.
Methods: We undertook a nested case-control study to analyse data from a population-based database (Cohort of Norway; CONOR), which consisted of prospectively obtained health data from all regions of Norway.
Am J Physiol Gastrointest Liver Physiol
February 2006
Malnutrition is common in the developing world, where tuberculosis is often endemic. Rabbits infected with aerosolized Mycobacterium tuberculosis that subsequently became inadvertently and transiently malnourished had compromised cell-mediated immunity comparable to that of the rabbits immunosuppressed with dexamethasone. They had significant leukopenia and reduced delayed-type hypersensitivity responses.
View Article and Find Full Text PDFPurpose: Walking can be incorporated into most people's daily routines if the process is made convenient by a well-designed built environment. Walkability rarely is assessed in the workplace, where adults spend much of their time.
Methods: From existing tools, we developed an instrument to audit walkability at a single government agency's facilities, which were located in multiple states.
Purpose: Recurrent respiratory papillomas, caused by human papillomaviruses, are premalignant tumors that overexpress the epidermal growth factor receptor (EGFR). The goals of this study were as follows: (a) to evaluate the expression of cyclooxygenase-2 (COX-2) in papillomas, (b) to investigate the role of EGFR signaling in COX-2 expression, and (c) to determine whether COX-2 activity is important for the growth of papilloma cells.
Experimental Design: Immunohistochemistry, Western blotting, and real-time PCR were used to determine levels of COX-2 in papilloma and normal laryngeal tissue.
Purpose: Increased levels of cyclooxygenase-2 and prostaglandin E2 (PGE2) have been observed in tobacco-related malignancies of the upper aerodigestive tract. Moreover, exposure to tobacco smoke can stimulate the synthesis of PGE2. Recent evidence suggests that urinary PGE metabolite (PGE-M) can be used as an index of systemic PGE2 production.
View Article and Find Full Text PDFActivation of epidermal growth factor receptor (EGFR)-mediated signaling has been implicated in the pathogenesis of tobacco smoke-induced cancers. Recently, elevated levels of amphiregulin, a ligand of the EGFR, were found in the oral mucosa of smokers. The main objective of this study was to elucidate the mechanism by which tobacco smoke induces amphiregulin.
View Article and Find Full Text PDFCyclooxygenase-2 (COX-2) is considered to be a target for anticancer therapy. Histone deacetylase (HDAC) inhibitors exhibit antitumor activity, but the mechanisms of action are incompletely understood. We investigated whether HDAC inhibitors blocked AP-1-mediated activation of COX-2 transcription.
View Article and Find Full Text PDFPurpose: To determine the effect of taxane-based chemotherapy on intratumoral levels of cyclooxygenase-2 (COX-2) and prostaglandin E(2) (PGE(2)) in patients with non-small cell lung cancer (NSCLC).
Experimental Design: Lung specimens obtained at the time of surgery were used to measure levels of COX-2 and PGE(2) in tumors and adjacent nontumorous tissues in three subsets of NSCLC patients who underwent: (A) surgical resection only (n = 16); (B) surgical resection after preoperative taxane-based chemotherapy (n = 13); or (C) surgical resection after preoperative chemotherapy coadministered with the selective COX-2 inhibitor, celecoxib 400 mg bid (n = 17).
Results: Levels of intratumoral PGE(2) were nearly 3-fold higher among patients who received preoperative chemotherapy compared with those treated by surgery alone (P < 0.
Introduction: In 2003, a major power outage occurred in the midwest and northeast United States affecting some 50 million people. The power outages affected multiple systems in state and local municipalities and, in turn, affected public health.
Methods: Semi-structured interviews were conducted using open-ended questionnaires, with a convenience sample of state- and locally selected subject matter experts from Ohio, Michigan, and New York.
Retinoids and their derivatives can suppress the development of cancer in animals and in humans. We and others have shown that retinoid X receptor (RXR)-selective retinoids or "rexinoids" suppress the development of breast cancer in several animal models with minimal toxicity. LGD1069 (Bexarotene) is a potent RXR-selective retinoid with reduced toxicity compared with naturally occurring retinoids.
View Article and Find Full Text PDFPurpose: Selective cyclooxygenase-2 (COX-2) inhibitors may suppress carcinogenesis by both COX-2-dependent and COX-2-independent mechanisms. The primary purpose of this study was to evaluate whether celecoxib or rofecoxib, two widely used selective COX-2 inhibitors, possess COX-2-independent antitumor activity.
Experimental Design: PC3 and LNCaP human prostate cancer cell lines were used to investigate the growth inhibitory effects of selective COX-2 inhibitors in vitro.
Cyclooxygenase-2 (COX-2) is a promising pharmacologic target for preventing aerodigestive malignancies. In this study, we investigated the effects of tobacco smoke on the expression of COX-2 in oral mucosa. An approximately 4-fold increase in amount of COX-2 mRNA was observed in the oral mucosa of active smokers versus never smokers.
View Article and Find Full Text PDFUnderstanding the mechanisms underlying carcinogenesis provides insights that are necessary for the development of therapeutic strategies to prevent cancer. Chemoprevention, the use of drugs or natural substances to inhibit carcinogenesis, is a rapidly evolving aspect of cancer research. Evidence is presented that cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) are potential pharmacologic targets to prevent cancer.
View Article and Find Full Text PDFThere is a significant body of evidence suggesting that enzymes involved in arachidonic acid metabolism and their eicosanoid products play a role in various cancers, having both pro- and antitumorigenic effects. The goal of this study was to further define the role microsomal prostaglandin E synthases (mPGES-1) play in lung tumorigenesis. Transgenic mice were created with targeted over-expression of human mPGES-1 in the alveolar and airway epithelial cells using an SP-C promoter driven construct.
View Article and Find Full Text PDFSeveral members of the P450 family, including cytochrome P450 1B1 (CYP1B1), can convert tobacco smoke (TS) procarcinogens, including benzo[a]pyrene (B[a]P), to carcinogenic intermediates. In this study we investigated the effects of TS condensate and B[a]P on the expression of CYP1B1 in vitro and in vivo. CYP1B1 mRNA and protein were induced by both TS condensate and B[a]P in cell lines derived from the human aerodigestive tract.
View Article and Find Full Text PDFBackground/aims: Cyclooxygenase-2 (COX-2) has been implicated in a number of hepatic stellate cell (HSC) functions but its relationship to transforming growth factor-beta 1 (TGF-beta 1)-mediated fibrogenesis is unknown. We assessed the impact of COX-2 inhibition and PGE(2) on the regulation of TGF-beta 1-stimulated matrix synthesis in an immortalized human HSC line, LX-1 and corroborated these findings in primary stellate cells.
Methods: Expression of COX-2 was assessed by Western blotting and real time quantitative PCR.
Evidence continues to accumulate that cyclooxygenase-2 (COX-2), an inducible COX isoform, represents a potential pharmacological target for the prevention and treatment of cancer, including tumors affecting the entire upper aerodigestive tract. Studies in experimental models of these malignancies show that selective COX-1 inhibitors reduce tumor formation and growth. Clinical studies have been initiated to determine the chemoprotective effects of selective COX-2 inhibitors in patients with oral leukoplakia and Barrett's esophagus, and other studies are assessing the feasibility of incorporating these agents into existing treatment modalities for patients with locally advanced or metastatic cancer.
View Article and Find Full Text PDFPurpose: Preclinical studies demonstrate a link between overexpression of HER-2/neu and cyclooxygenase-2 (COX-2) activity. To explore the possibility that COX-2 is a therapeutic target, we conducted a phase II study of celecoxib, a selective COX-2 inhibitor, and trastuzumab in patients with HER-2/neu-overexpressing metastatic breast cancer that had progressed while receiving trastuzumab.
Experimental Design: Eligible patients had bi-dimensionally measurable or evaluable HER-2/neu-overexpressing metastatic breast cancer.
Context: Use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) has been associated with a decrease in the risk of several cancers, including breast cancer. NSAIDs inhibit cyclooxygenase activity and thereby reduce prostaglandin synthesis; prostaglandins stimulate aromatase gene expression and thereby stimulate estrogen biosynthesis. Given the importance of estrogen in the pathogenesis of breast cancer, the ability of aspirin and other NSAIDs to protect against breast cancer could vary according to hormone receptor status.
View Article and Find Full Text PDFAlcoholic liver disease is associated with a state of hepatic fatty acid overload. We examined the effect of ethanol and different types of dietary fat on the expression of mRNA for liver fatty acid binding protein (L-FABP), peroxisome proliferator-activated receptor-alpha (PPARalpha), and peroxisomal fatty acyl CoA oxidase (FACO). Four groups of rats (n = 5) were fed intragastrically, a liquid diet with or without ethanol (10-16 g/kg/day) for 4 weeks.
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