1000 resultados para 337.142


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Objective. To investigate the modes of water supply and the perception concerning the problems caused by this water among residents of a neighborhood without public supply of water, settled in an area previously used as a garbage dump in the city of Manaus, Brazil. Methods. One hundred and sixty-two semi-structured household interviews were conducted. In addition, a focal group with teachers from a local public school and a meeting with residents were held. The instruments employed focused on the perception and modes of water use and on the process of exposure to chemical contaminants through water. Results. Untreated well water was used by most families. This water was considered to be ""good"" by 64.8% of the individuals interviewed. Most residents (88.3%) declared knowledge about the garbage dump. Of these, 77.6% stated that the garbage dump caused health and environmental problems. However, qualitative analysis of the responses revealed that the residents were not aware of contamination by chemical elements or of the consequences of such contamination. The activities carried out with teachers revealed that they were partially aware of the problem, but did not design interventions to address the issue. In a meeting with neighborhood residents, the presence of social activism concerning the problem was identified, but it did not extend beyond the neighborhood or reach governmental spheres. Conclusions. The study identified a situation of critical exposure that tends to be maintained as a result of misperceptions and lack of social mobilization. The dissemination of research results to teachers and residents was useful to empower subjects.

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OBJECTIVE To demonstrate the impact on perinatal mortality of inadequate treatment for maternal syphilis despite adequate screening. METHOD In 12 clinics providing antenatal care in Hlabisa, South Africa 1783 pregnant women were screened for syphilis at their first antenatal visit between June and October 1998. Pregnancy outcome was determined among those with syphilis. RESULTS A total of 158 women were diagnosed with syphilis: prevalence 9% (95% CI 8-10%). Mean gestation at first antenatal visit was 24 weeks. Thirty women (19%) received no treatment and 96 (61%) received all three recommended doses of penicillin. Among those receiving at least one dose, mean delay to the first dose was 20 days. Among those fully treated mean delay to treatment completion was 34 days. Pregnancy outcome was known for 142 women (90%) and there were 17 perinatal deaths among 15 women (11%). Eleven of 43 women (26%) who received one or fewer doses of penicillin experienced ii perinatal death whilst only four of 99 women (4%) who received two or more doses of penicillin did so (P = 0.0001). Protection from perinatal death increased with the number of doses of penicillin: linear modelling suggests that one dose reduced the risk by 41%, two doses by 65% and three doses by 79%, compared with no doses. A dose-specific, categorical model confirmed reduction in risk by 79% for all three doses. CONCLUSION Despite effective screening, many pregnant women with syphilis remain inadequately treated, resulting in avoidable perinatal mortality. Delays in starting and finishing treatment, as well as incomplete treatment occur. Near-patient syphilis testing in the antenatal clinic with early treatment could improve treatment of syphilis and reduce perinatal mortality, and a randomized trial to test this is underway.

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A flow chamber was used to impart a steady laminar shear stress on a recombinant Chinese hamster ovary (CHO) cell line expressing human growth hormone (hGH). The cells were subjected to shear stress ranging from 0.005 to 0.80 N m(-2). The effect of shear stress on the cell specific glucose uptake, cell specific hGH, and lactate productivity rates were calculated. No morphological changes to the cells were observed over the range of shear stresses examined. When the cells were subjected to 0.10 N m(-2) shear in protein-free media without Pluronic F-68, recombinant protein production ceased with no change in cell morphology, whereas control cultures were expressing hGH at 0.35 mug/10(6) cells/h. Upon addition of the shear protectants, Pluronic F-68 (0.2% [w/v]) or fetal bovine serum (1.0% [v/v] FBS), the productivity of the cells was restored. The effect of increasing shear stress on the cells in protein-free medium containing Pluronic F-68 was also investigated. Cell specific metabolic rates were calculated for cells under shear stress and for no-shear control cultures performed in parallel, with shear stress rates expressed as a percentage of those obtained for control cultures. Upon increasing shear from 0.005 to 0.80 N m(-2), the cell specific hGH productivity decreased from 100% at 0.005 N m(-2) to 49% at 0.80 N m(-2) relative to the no-shear control. A concurrent increase in the glucose uptake rate from 115% at 0.01 N m(-2) to 142% at 0.80 N m(-2), and decreased lactate productivity from 92% to 50%, revealed a change in the yield of products from glucose compared with the static control. It was shown that shear stress, at sublytic levels in medium containing Pluronic F-68, could decrease hGH specific productivity. (C) 2002 Wiley Periodicals, Inc.

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Tarpon have high resting or routine hematocrits (Hct) (37.6+/-3.4%) and hemoglobin concentrations (120.6+/-7.3 g 1(-1)) that increased significantly following bouts of angling-induced exercise (51.9+/-3.7% and 142.8+/-13.5 g 1(-1), respectively). Strenuous exercise was accompanied by an approximately tenfold increase in blood lactate and a muscle metabolite profile indicative of a high energy demand teleost. Routine blood values were quickly restored only when this facultative air-breathing fish was given access to atmospheric air. In vitro studies of oxygen transport capacity, a function of carrying capacity and viscosity, revealed that the optimal Hct range corresponded to that observed in fish under routine behaviour. During strenuous exercise however, further increase in viscosity was largely offset by a pronounced reduction in the shear-dependence of blood which conformed closely to an ideal Newtonian fluid. The mechanism for this behaviour of the erythrocytes appears to involve the activation of surface adrenergic receptors because pre-treatment with propranolol abolished the response. High levels of activity in tarpon living in hypoxic habitats are therefore supported by an elevated Hct with adrenergically mediated viscosity reduction, and air-breathing behaviour that enables rapid metabolic recovery. (C) 2002 Elsevier Science Inc. All rights reserved.

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in Escherichia coli, the DnaG primase is the RNA polymerase that synthesizes RNA primers at replication forks. It is composed of three domains, a small N-terminal zinc-binding domain, a larger central domain responsible for RNA synthesis, and a C-terminal domain comprising residues 434-581 [DnaG(434-581)] that interact with the hexameric DnaB helicase. Presumably because of this interaction, it had not been possible previously to express the C-terminal domain in a stably transformed E coli strain. This problem was overcome by expression of DnaG(434-581) under control of tandem bacteriophage gimel-promoters, and the protein was purified in yields of 4-6 mg/L of culture and studied by NMR. A TOCSY spectrum of a 2 mM solution of the protein at pH 7.0, indicated that its structured core comprises residues 444-579. This was consistent with sequence conservation among most-closely related primases. Linewidths in a NOESY spectrum of a 0.5 mM sample in 10 mM phosphate, pH 6.05, 0.1 M NaCl, recorded at 36 degreesC, indicated the protein to be monomeric. Crystals of selenomethionine-substituted DnaG(434-581) obtained by the hanging-drop vapor-diffusion method were body-centered tetragonal, space group I4(1)22, with unit cell parameters a = b 142.2 Angstrom, c = 192.1 Angstrom, and diffracted beyond 2.7 Angstrom resolution with synchrotron radiation. (C) 2003 Elsevier Inc. All rights reserved.

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In this work, we studied the oxidation of the azo dye Disperse orange 3 (DO3) by hydrogen peroxide, catalyzed by 5,10,15, 20-tetrakis(4-N-methylpyridyl)porphyrin iron(III) chloride immobilized onto montmorillonite K10, FeP-K10. Results showed that the FeP-K10/H2O2 system is efficient for discoloration of the DO3 dye, especially at pH 3.0. The catalyst was shown to be relatively stable and could be recycled many times, leading to good yields. DO3 oxidation products were analyzed by gas chromatography and mass spectrometry, being 4-nitroaniline the main product. Tert-butylhydroperoxide and iodosylbenzene were also used as oxidants, giving rise to 4-nitroaniline as product too. The studied system is a good biomimetic model of oxidative enzymes, being a promising discoloring agent for azo dyes. (C) 2007 Elsevier Ltd. All rights reserved.

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A modification of the Pechini method was applied to obtain luminescent rare earth orthophosphates. The developed synthetic route is based on the ability of the tripolyphosphate anion (P3O105-) to act both as a complexing agent and as an orthophosphate precursor. Heating of aqueous solutions containing RE3+, Eu3+, P3O105-, citric acid, and ethylene glycol led to polymeric resins. The ignition of these resins at different temperatures yielded luminescent orthophosphates. The produced nanosized phosphors (YPO4:Eu3+, (Y,Gd)PO4:Eu3+, and LaPO4:Eu3+) were analyzed by infrared and luminescence spectroscopies, X-ray diffractometry, and scanning electron microscopy.

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We consider a kinetic Ising model which represents a generic agent-based model for various types of socio-economic systems. We study the case of a finite (and not necessarily large) number of agents N as well as the asymptotic case when the number of agents tends to infinity. The main ingredient are individual decision thresholds which are either fixed over time (corresponding to quenched disorder in the Ising model, leading to nonlinear deterministic dynamics which are generically non-ergodic) or which may change randomly over time (corresponding to annealed disorder, leading to ergodic dynamics). We address the question how increasing the strength of annealed disorder relative to quenched disorder drives the system from non-ergodic behavior to ergodicity. Mathematically rigorous analysis provides an explicit and detailed picture for arbitrary realizations of the quenched initial thresholds, revealing an intriguing ""jumpy"" transition from non-ergodicity with many absorbing sets to ergodicity. For large N we find a critical strength of annealed randomness, above which the system becomes asymptotically ergodic. Our theoretical results suggests how to drive a system from an undesired socio-economic equilibrium (e. g. high level of corruption) to a desirable one (low level of corruption).

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The preset study adopted an intergroup approach to information sharing and communication in three organisational samples during change. In Study 1, employees from a public hospital (N = 142) completed a survey measuring perceptions of organisational communication and strength of identification with the work unit and the organisation as a whole. Consistent with predictions, team members rated communication from double ingroup members (same work unit/same occupational group) more favourably than communication from partial group members (same work unit/different occupational group). Also as predicted, work unit identification was related to favourable ratings of work unit communication across occupational groups, whereas occupational identification was related to favourable ratings of work unit communication within occupational groups. In Study 2, strength of identification with three organisational groups was associated with positive ratings of communication among employees from the same public hospital (N = 189) and a military organisation (N = 2119). Based on these results, intergroup strategies for the management of information sharing and organisational communication during change are discussed.

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Aims: There remains significant concern about the long-term safety of drug-eluting stents (DES). However, bare metal stents (BMS) have been used safely for over two decades. There is therefore a pressing need to explore alternative strategies for reducing restenosis with BMS. This study was designed to examine whether IVUS-guided cutting balloon angioplasty (CBA) with BMS could convey similar restenosis rates to DES. Methods and results: In the randomised REstenosis reDUction by Cutting balloon angioplasty Evaluation (REDUCE III) study, 521 patients were divided into four groups based on device and IVUS use before BMS (IVUS-CBA-BMS: 137 patients; Angio-CBA-BMS: 123; IVUS-BA-BMS: 142; and Angio-BA-BMS: 119). At follow-up, the IVUS-CBA-BMS group had a significantly lower restenosis rate (6.6%) than the other groups (p=0.016). We performed a quantitative coronary angiography (QCA) based matched comparison between an IVUS-guided CBA-BMS strategy (REDUCE III) and a DES strategy (Rapamycin-Eluting-Stent Evaluation At Rotterdam Cardiology. Hospital, the RESEARCH study). We matched the presence of diabetes, vessel size, and lesion severity by QCA. Restenosis (>50% diameter stenosis at follow-up) and target vessel revascularisation (TVR) were examined. QCA-matched comparison resulted in 120-paired lesions. While acute gain was significantly greater in IVUS-CBA-BMS than DES (1.65 +/- 0.41 mm vs. 1.28 +/- 0.57 mm, p=0.001), late loss was significantly less with DES than with IVUS-CBA-BMS (0.03 +/- 0.42 mm vs. 0.80 +/- 0.47 mm, p=0.001). However, no difference was found in restenosis rates (IVUS-CBA-BMS: 6.6% vs. DES: 5.0%, p=0.582) and TVR (6.6% and 6.6%, respectively). Conclusions: An IVUS-guided CBA-BMS strategy yielded restenosis rates similar to those achieved by DES and provided an effective alternative to the use of DES.

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Background: To investigate the association between cardiovascular risk-factor profile and migraine in the elderly, we evaluated a population sample of ageing men and women (65 years or more) living in a low-income area in the city of Sao Paulo, Brazil. Patients and Methods: We investigated migraine status and cardiovascular profile from a baseline of 1450 participants (65-102 years of age) of the Sao Paulo Ageing & Health Study (SPAH), a longitudinal population-based study with low-income elderly in Brazil. The following age and sex-adjusted cardiovascular risk factors were analyzed: blood pressure, pulse pressure, serum total and high-density lipoprotein cholesterol, body mass index, smoking, history of hypertension, diabetes and the 10-year risk of myocardial infarction or coronary heart disease death based on the Framingham Risk Score. Results: The overall prevalence of migraine was 11.4%, and it was 3 times more frequent among women than men (15.3% vs 5.4%; P < 0.0001). Migraineurs were younger than non-migraineurs (mean age 70.6 years vs 72.1 years; P = 0.001, respectively). There was no statistically significant difference regarding the cardiovascular risk-factor profile after adjustment for age and sex among migraineurs and non-migraineurs. Only a decrease in the risk of hypertension among women (OR 0.58; 95% CI 0.38-0.90; P = 0.01) was also observed even after adjustment for age. Conclusions: Overall, we did not find a worse cardiovascular risk profile among elderly migraineurs. An inverse association between hypertension and migraine in women warrants further investigation.

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Objectives: We sought to compare long-term outcomes after coronary bypass surgery with and without an internal thoracic artery graft. Methods: We analyzed clinical outcomes over a median follow-up of 6.7 years among 3,087 patients who received coronary bypass surgery as participants in one of 8 clinical trials comparing surgical intervention with angioplasty. We used 2 statistical methods (covariate adjustment and propensity score matching) to adjust for the nonrandomized selection of internal thoracic artery grafts. Results: Internal thoracic artery grafting was associated with lower mortality, with hazard ratios of 0.77 (confidence interval, 0.62-0.97; P = .02) for covariate adjustment and 0.77 (confidence interval, 0.57-1.05; P = .10) for propensity score matching. The composite end point of death or myocardial infarction was reduced to a similar extent, with hazard ratios of 0.83 (confidence interval, 0.69-1.00; P = .05) for covariate adjustment to 0.78 (confidence interval, 0.61-1.00; P = .05) for propensity score matching. There was a trend toward less angina at 1 year, with odds ratios of 0.81 (confidence interval, 0.61-1.09; P = .16) in the covariate-adjusted model and 0.81 (confidence interval, 0.55-1.19; P = .28) in the propensity score-adjusted model. Conclusions: Use of an internal thoracic artery graft during coronary bypass surgery seems to improve long-term clinical outcomes. (J Thorac Cardiovasc Surg 2011; 142: 829-35)

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We compared four strategies for inviting 91,456 women aged 50-69 years to one of six clinics for mammography screening and 40,142 men aged 60-79 years to one of 10 clinics for abdominal aortic aneurysm (AAA) screening. The strategies were invitation to the clinic nearest to the client and invitation to the clinic nearest to the client's area of residence defined by census small area, postcode and local government area. For each strategy we calculated the expected demand at each clinic and the travel distances for clients. We found that when women were allocated to mammography clinics on the basis of the local government area instead of their individual address, expected demand at one clinic increased by 60%, and 19% of clients were invited to attend a more remote clinic, entailing 99,000 km of additional travel. Similar results were obtained for men allocated to AAA clinics by their postcode of residence instead of their individual address: 55% difference in expected demand, 13% to a more remote clinic and 60,000 km of extra travel. Allocation on the basis of small areas did not show such great differences, except for travel distance, which was about 5% higher for each clinic type. We recommend that allocation of clients to screening clinics be made according to residential address, that assessment of the location of clinics be based on distances between residences and nearest clinic, but that planning new locations for clinics be aided with spatial analysis tools using small area demographic and social data. (C) 1997 Elsevier Science Ltd.

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Background and objective: Hyperinflation with a decrease in inspiratory capacity (IC) is a common presentation for both unstable and stable COPD patients. As CPAP can reduce inspiratory load, possibly secondary to a reduction in hyperinflation, this study examined whether CPAP would increase IC in stable COPD patients. Methods: Twenty-one stable COPD patients (nine emphysema, 12 chronic bronchitis) received a trial of CPAP for 5 min at 4, 7 and 11 cmH(2)O. Fast and slow VC (SVC) were measured before and after each CPAP trial. In patients in whom all three CPAP levels resulted in a decreased IC, an additional trial of CPAP at 2 cmH(2)O was conducted. For each patient, a `best CPAP` level was defined as the one associated with the greatest IC. This pressure was then applied for an additional 10 min followed by spirometry. Results: Following application of the `best CPAP`, the IC and SVC increased in 15 patients (nine emphysema, six chronic bronchitis). The mean change in IC was 159 mL (95% CI: 80-237 mL) and the mean change in SVC was 240 mL (95% CI: 97-386 mL). Among these patients, those with emphysema demonstrated a mean increase in IC of 216 mL (95% CI: 94-337 mL). Six patients (all with chronic bronchitis) did not demonstrate any improvement in IC. Conclusions: The best individualized CPAP can increase inspiratory capacity in patients with stable COPD, especially in those with emphysema.

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The PKC apoptosis WTI regulator gene, also named prostate apoptosis response-4 (PAR-4), encodes a pro-apoptotic protein that sensitizes cells to numerous apoptotic stimuli. Insulin-like growth factor-1 (IGF-1) and 17 beta-estradiol (E2), two important factors for breast cancer development and progression, have been shown to down-regulate PAR-4 expression and inhibit apoptosis induced by PAR-4 in neuronal cells. In this study, we sought to investigate the mechanisms of regulation of PAR-4 gene expression in MCF-7 cells treated with E2 or IGF-1. E2 (10 nM) and IGF-1 (12.5 nM) each down-regulated PAR-4 expression in MCF-7 cells after 24 h of treatment. The effect of E2 was dependent on ER activation, as demonstrated by an increase in PAR-4 expression when cells were pretreated for 1 h with 1 mu M ICI-182,780 (ICI) before receiving E2 plus ICI. The effect of IGF-1 was abolished by pre-treatment for 1 h with 30 mu M LY294002 (a specific PI3-K inhibitor), and significantly inhibited by 30 mu M SB202190 (a specific p38MAPK inhibitor). We also demonstrated that E2 acts synergistically with IGF-1, resulting in greater down-regulation of PAR-4 mRNA expression compared with E2 or IGF-1 alone. Our results show for the first time that E2 and IGF-1 inhibit PAR-4 gene expression in MCF-7 cells, suggesting that this down-regulation may provide a selective advantage for breast cancer cell survival.