2,173 research outputs found
New method for critical failure prediction of complex systems
Rigorous analytical technique, called criticality determination methodology /or CD technique/ determines the probability that a given complex system will successfully achieve stated objectives. The CD technique identifies critical elements of the system by a failure mode and effects analysis
Promoting physical activity in patients with colon adenomas: a randomized pilot intervention trial
BACKGROUND: Physical activity decreases risk of colon polyps and colon cancer and might reduce risk of colon cancer recurrence. Focusing on recent calls for translation of epidemiologic evidence into clinical care, our pilot study delivered an evidence-based physical activity intervention in adults with polyps, who are thus at elevated risk of developing colon cancer. The objective was to evaluate change in physical activity, measured by steps per day and minutes of moderate/vigorous physical activity. METHODS: Sixteen adults with adenomas detected and removed at screening colonoscopy were recruited to a 12-week physical activity intervention. Participants were randomized to receive a standard (30 minutes/day) or high (60 minutes/day) walking program. Physical activity was measured via blinded pedometer and accelerometer at baseline and follow-up. Intervention messages focused on self-monitoring using pedometers and overcoming barriers to engaging in physical activity. RESULTS: Participants in both arms significantly increased objectively measured minutes of moderate/vigorous physical activity over the course of the intervention. Both arms exceeded the intervention goal, but there was not a significant difference between arms at follow-up. Results were similar for pedometer measured physical activity, with a significant overall increase in steps/day from baseline to follow-up, but no between arm difference in change. CONCLUSION: Simple interventions of minimal contact time focusing on walking can significantly increase physical activity in individuals at increased risk of developing colon cancer. TRIAL REGISTRATION: ClinicalTrials.gov NCT0147663
Comparison of spectra of single sideband and phase modulated signals
Comparison of spectra of single-sideband and phase modulated signal
ROLE OF ENDOTHELIUM-DERIVED PROSTAGLANDINS IN HYPOXIA-ELICITED ARTERIOLAR DILATION IN RAT SKELETAL-MUSCLE
The aims of the present study were to determine the response of rat cremaster muscle first-order arterioles to hypoxia and the role of endothelium-derived prostaglandins in the response. Isolated arterioles were cannulated, pressurized to 65 mm Hg, and studied in a no-flow condition in a bath containing Krebs' bicarbonate solution, pH 7.4, equilibrated with 21% O2-5% CO2-74% N2 (PO2, 150 mm Hg) or 95% N2-5% CO2 (Po2, 15 mm Hg [hypoxia]). Responses to hypoxia and vasoactive substances were studied before and after removal of the endothelium or blockade of prostaglandin synthesis by the administration of indomethacin (10(-5) M). Addition to the suffusion solution of arachidonic acid (10(-7) and 10(-6) M), prostaglandin E2 (10(-9) and 10(-8) M), acetylcholine (10(-8) and 10(-6) M), or sodium nitroprusside 10(-8) M) evoked significanT arteriolar dilation. When the bath Po2 was reduced from 150 to 15 mm Hg, arteriolar diameters increased by 58.8+/-9.3-mu-m (61%). Removal of the endothelium completely inhibited responses to hypoxia, acetylcholine, and arachidonic acid, whereas responses to sodium nitroprusside and prostaglandin E2 remained unaltered. In arterioles with an intact endothelium, indomethacin completely inhibited the responses to hypoxia and arachidonic acid, whereas responses to acetylcholine and sodium nitroprusside were unaltered. These findings support the conclusion that endothelium-derived prostaglandins mediate the arteriolar dilation to hypoxia in rat skeletal muscle arterioles
High pressure induces superoxide production in isolated arteries viaprotein kinase C-dependent activation of NAD(P)H oxidase
Background - Oxidative stress seems to be present in all forms of hypertension. Thus, we tested the hypothesis that high intraluminal pressure (P-i) itself, by activating vascular oxidases, elicits increased superoxide (O-2(.-)) production interfering with flow-induced dilation. Methods and Results - Isolated, cannulated rat femoral arterial branches were exposed in vitro ( for 30 minutes) to normal P-i (80 mm Hg) or high P-i (160 mm Hg). High P-i significantly increased vascular O-2(.-) production ( as measured by lucigenin chemiluminescence and ethidium bromide fluorescence) and impaired endothelium-dependent dilations to flow; these effects could be reversed by superoxide dismutase. Administration of the NAD(P)H oxidase inhibitor diphenyleneiodonium, apocynin, the protein kinase C (PKC) inhibitor chelerythrine or staurosporin or the removal of extracellular Ca2+ during high P-i treatment prevented the increases in O-2(.-) production, whereas administration of losartan or captopril had no effect. High P-i resulted in significant increases in intracellular Ca2+ ([Ca2+](i)) in the vascular wall ( fura 2 fluorescence) and phosphorylation of PKCalpha ( Western blotting). The PKC activator phorbol myristate acetate significantly increased vascular O-2(.-) production, which was inhibited by superoxide dismutase, diphenyleneiodonium, chelerythrine, or removal of extracellular Ca2+. Both high P-i and phorbol myristate acetate increased the phosphorylation of the NAD( P) H oxidase subunit p47(phox). Conclusion - High P-i itself elicits arterial O-2(.-) production, most likely by PKC-dependent activation of NAD( P) H oxidase, thus providing a potential explanation for the presence of oxidative stress and endothelial dysfunction in various forms of hypertension and the vasculoprotective effect of antihypertensive agents of different mechanisms of action
Refugees, trauma and adversity-activated development
The nature of the refugee phenomenon is examined and the position of mental health professionals is located in relation to it. The various uses of the word 'trauma' are explored and its application to the refugee context is examined. It is proposed that refugees' response to adversity is not limited to being traumatized but includes resilience and Adversity-Activated Development (AAD). Particular emphasis is given to the distinction between resilience and AAD. The usefulness of the 'Trauma Grid' in the therapeutic process with refugees is also discussed. The Trauma Grid avoids global impressions and enables a more comprehensive and systematic way of identifying the individual refugee's functioning in the context of different levels, i.e. individual, family, community and society/culture. Finally, I discuss implications for therapeutic work with refugees
Screening and Health Behaviors among Persons Diagnosed with Familial Adenomatous Polyposis and Their Relatives
Familial Adenomatous Polyposis (FAP) is a rare autosomal dominantly inherited colorectal cancer syndrome. Individuals with FAP often undergo colectomy and are recommended to follow several surveillance protocols. Biological relatives of persons with FAP may also be at risk and thus should undergo genetic counseling. Screening adherence, genetic testing, and other health behaviors among individuals with FAP and their relatives are not well characterized. We conducted a cross-sectional self-report survey with individuals who have FAP (n=35) and their biological relatives (n=15). Respondents were recruited through a cancer center registry for inherited colon cancers. Most relatives had undergone colon cancer screening; 40% had undergone genetic testing. One fifth of respondents with FAP had not undergone an upper endoscopy, contrary to usual recommendations. Cigarette smoking rates were above average and were higher among FAP respondents. Use of vitamin supplements was fairly common, more so among those with FAP. Although most people had been screened, there are areas for improvement, notably for upper endoscopy among individuals with FAP and genetic testing among family members. Several other health-risk behaviors and health concerns other than FAP were identified. Further research into factors contributing to screening rates and other health behaviors in this high-risk population is warranted
- …