465 research outputs found

    Effects of Dietary Fiber Intake on Cardiovascular Risk Factors

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    A healthy dietary pattern is characterized by a high consumption of non-refined grains, legumes, nuts, fruits and vegetables; relatively high intake of total fat, mainly derived from olive oil; moderate to high intake of fish and poultry; dairy products (usually as yogurt or cheese) in small amounts; low consumption of red meat and meat products; and moderate alcohol intake, usually in the form of red wine with meals (Willett et al., 1995). Therefore, a high consumption of fiber-rich foods is one of the characteristic features of a healthy diet. Dietary fiber (DF) has received much attention in nutritional epidemiology. Observational studies have consistently shown that DF intake is associated with reduced cardiovascular risk, including ischemic heart disease (Rimm et al., 1996a; Todd et al., 1999; Liu et al., 2002; Mozaffarian et al., 2003a) and stroke (Ascherio et al., 1998; Oh et al., 2005; Salmeron et al., 1997)), and a lower risk of diabetes (Meyer et al., 2000; Liu, 2003b). Clinical trials have also suggested that DF supplementation has beneficial effects on risk factors, such as blood pressure, serum lipids, insulin sensitivity and diabetic metabolic control (Streppel et al., 2005b; Brown et al., 1999; Anderson et al., 2000; Chandalia et al., 2000a; Ludwig et al., 1999)

    Isolation of ntrA-like mutants of Azobacter vinelandii

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    A number of of chlorate-resistant mutants of Azotobacter vinelandii affected in a general control of nitrogen metabolism were isolated. These mutants could not utilize dinitrogen, nitrate, or nitrite as a nitrogen source. The reason for this inability is that they were simultaneously deficient in nitrogenase and nitrate and nitrite reductase activities. They were complemented by a cosmid carrying a DNA fragment of A. vinelandii able to complement ntrA mutants of Escherichia coli, so they seemed to be ntrA-like mutants.Comisión Asesora Científica y Técnica 302

    Study of extraordinary transmission in a circular waveguide system

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    Extraordinary transmission through periodic distributions of sub-wavelength holes made in opaque screens has been demonstrated and exhaustively studied along the last decade. More recently, extraordinary transmission has also been predicted and experimentally observed through electrically small diaphragms located inside hollow pipe waveguides. This last phenomenon cannot be explained in terms of surface waves excited along the periodic system (the so-called surface plasmon polaritons). Transverse resonances can be invoked, however, as a sound explanation for extraordinary transmission in this kind of systems. In this paper, a simple waveguide system, exhibiting exactly the same behavior previously observed in periodic 2-D arrays of holes, is analyzed in depth. Analogies and differences with the periodic case are discussed. The theoretical and experimental results reported in this paper provide strong evidence in favor of the point of view emphasizing the concept of impedance matching versus surface wave excitation. The role of material losses is discussed as an important practical issue limiting the maximum achievable subwavelength transmission level. Most of our conclusions can be applied to both periodic arrays of holes and diaphragms in closed waveguides.Ministerio de Ciencia e Innovación TEC2007-65376, CSD2008-00066Junta de Andalucía TIC-459

    Evaluation of COX-2, EGFR, and p53 as biomarkers of non-dysplastic oral leukoplakias

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    [Abstract] Objective. Identify candidate SEBs (surrogate endpoint biomarkers) for premalignant trends in head and neck mucosa. Study design. Study, by qPCR (quantitative real-time polymerase chain reaction), the expression of COX-2, EGFR and p53 in 24 biopsies of non-dysplastic oral leukoplakia and contra-lateral normal-appearing mucosa. Results. COX-2 was up-regulated in leukoplakia (79.2%); whereas EGFR and p53 were up-regulated (p > 0.05) in oral contra-lateral normal-appearing mucosa (60% and 46% respectively). Also, p53 expression was correlated with tobacco smoke habits and Spearman's rank correlation coefficient showed a positive linear correlation between p53 and EGFR mRNA expression levels. Conclusions. COX-2 would serve as SEB of oral leukoplakia. The results suggest that p53 appears to be one of the molecular targets of tobacco-related carcinogens in leukoplakia and that the co-expression of p53 and EGFR may play a role in this kind of oral pre-cancerous lesion. More detailed studies of EGFR and p53 should be continued in the future

    Growth of Escherichia coli in human milk and powdered infant formula under various treatments and feeding conditions in neonatal units

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    Milk supplied to neonates in neonatal units is kept at room temperature for some time, which could influence microbial growth. This study aims to evaluate the growth of Escherichia coli in HM and PIF under various treatments and conditions, as well as to determine the influence of different thawing methods on microbial growth in HM. The number of E. coli generations appearing over a 4 h period at 22 °C in HM (frozen; frozen and pasteurized; and frozen, pasteurized, and fortified) and in PIF (four brands) was determined. E. coli counts in HM inoculated and thawed using different methods were also compared. In frozen HM and in pasteurized and frozen HM, significant differences were found after 2.5 h and 1.5 h, respectively. In PIF, differences were found between 1.5 and 3 h. With regard to the thawing process, the lowest microorganism counts were obtained at 4 °C overnight; thus, it seems advisable to store milk at room temperature for a maximum of 1 h during administration in neonatal units. Thawing HM at 4 °C overnight should be the method of choice

    Extreme Temperatures and Mortality: Assessing Effect Modification by Personal Characteristics and Specific Cause of Death in a Multi-City Case-Only Analysis

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    BACKGROUND: Extremes of temperature are associated with short-term increases in daily mortality. OBJECTIVES: We set out to identify subpopulations and mortality causes with increased susceptibility to temperature extremes. METHODS: We conducted a case-only analysis using daily mortality and hourly weather data from 50 U.S. cities for the period 1989–2000, covering a total of 7,789,655 deaths. We used distributions of daily minimum and maximum temperature in each city to define extremely hot days (≥ 99th percentile) and extremely cold days (≤ 1st percentile), respectively. For each (hypothesized) effect modifier, a city-specific logistic regression model was fitted and an overall estimate calculated in a subsequent meta-analysis. RESULTS: Older subjects [odds ratio (OR) = 1.020; 95% confidence interval (CI), 1.005–1.034], diabetics (OR = 1.035; 95% CI, 1.010–1.062), blacks (OR = 1.037; 95% CI, 1.016–1.059), and those dying outside a hospital (OR = 1.066; 95% CI, 1.036–1.098) were more susceptible to extreme heat, with some differences observed between those dying from a cardiovascular disease and other decedents. Cardiovascular deaths (OR = 1.053; 95% CI, 1.036–1.070), and especially cardiac arrest deaths (OR =1.137; 95% CI, 1.051–1.230), showed a greater relative increase on extremely cold days, whereas the increase in heat-related mortality was marginally higher for those with coexisting atrial fibrillation (OR = 1.059; 95% CI, 0.996–1.125). CONCLUSIONS: In this study we identified several subpopulations and mortality causes particularly susceptible to temperature extremes. This knowledge may contribute to establishing health programs that would better protect the vulnerable

    The Role of the Entorhinal Cortex in Extinction: Influences of Aging

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    The entorhinal cortex is perhaps the area of the brain in which neurofibrillary tangles and amyloid plaques are first detectable in old age with or without mild cognitive impairment, and very particularly in Alzheimer's disease. It plays a key role in memory formation, retrieval, and extinction, as part of circuits that include the hippocampus, the amygdaloid nucleus, and several regions of the neocortex, in particular of the prefrontal cortex. Lesions or biochemical impairments of the entorhinal cortex hinder extinction. Microinfusion experiments have shown that glutamate NMDA receptors, calcium and calmodulin-dependent protein kinase II, and protein synthesis in the entorhinal cortex are involved in and required for extinction. Aging also hinders extinction; it is possible that its effect may be in part mediated by the entorhinal cortex

    Chemical pneumonitis and subsequent reactive airways dysfunction syndrome after a single exposure to a household product: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Household products are usually safe to use. Adverse events arising from their use are mostly reported in patients with pre-existing atopy or pulmonary problems and usually only after a prolonged exposure to such products. We report the case of a patient with no prior problems who developed significant side effects from a single exposure to a domestic product.</p> <p>Case presentation</p> <p>A 43-year-old Caucasian American man, previously in good health, used a domestic aerosol product called 'Stand N' Seal "Spray-On" Grout Sealer' in an enclosed room in his house. The product contained n-butyl acetate (<5%), propane (10%), isobutane (<5%), C8-C9 petroleum hydrocarbon solvent (80%), a fluoropolymer resin and a solvent. Within a few hours of exposure to the sealant, he developed rapidly progressive shortness of breath and a severe non-productive cough. By the time he reached the emergency room he was severely hypoxic. A diagnosis of chemical pneumonitis was made based on the clinical scenario and the diffuse infiltrates on the computer tomography scan. With supportive therapy, his condition improved and he was discharged from the hospital. However, he continued to have symptoms of intermittent cough and shortness of breath in response to strong odours, fumes, cold air and exertion even after his chest radiograph had normalized. Three months later, bronchial hyper-responsiveness was documented by a methacholine inhalation test and a diagnosis of reactive airways dysfunction syndrome was made. The patient was started on high-dose inhaled steroids and his symptoms improved. The mechanism of toxicity and determination of the exact agent responsible is still under investigation.</p> <p>Conclusion</p> <p>A household product may still prove unsafe to use even after it has gone through vigorous testing and approval processes. Even healthy individuals are susceptible to adverse outcomes after a brief exposure. Extra precautions should be taken when using any chemical product at home.</p
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