93 resultados para Slater, Michelle
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This paper is devoted to the study of the class of continuous and bounded functions f : [0, infinity] -> X for which exists omega > 0 such that lim(t ->infinity) (f (t + omega) - f (t)) = 0 (in the sequel called S-asymptotically omega-periodic functions). We discuss qualitative properties and establish some relationships between this type of functions and the class of asymptotically omega-periodic functions. We also study the existence of S-asymptotically omega-periodic mild solutions of the first-order abstract Cauchy problem in Banach spaces. (C) 2008 Elsevier Inc. All rights reserved.
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We study the existence of asymptotically almost periodic classical solutions for a class of abstract neutral integro-differential equation with unbounded delay. A concrete application to partial neutral integro-differential equations which arise in the study of heat conduction in fading memory material is considered. (C) 2011 Elsevier Inc. All rights reserved.
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In insects, exoskeleton (cuticle) formation at each molt cycle includes complex biochemical pathways wherein the laccase enzymes (EC 1.10.3.2) may have a key role. We identified an Amlac2 gene that encodes a laccase2 in the honey bee, Apis mellifera, and investigated its function in exoskeleton differentiation. The Amlac2 gene consists of nine exons resulting in an ORE of 2193 nucleotides. The deduced translation product is a 731 amino acid protein of 81.5 kDa and a pl of 6.05. Amlac2 is highly expressed in the integument of pharate adults, and the expression precedes the onset of cuticle pigmentation and the intensification of sclerotization. In accordance with the temporal sequence of exoskeleton differentiation from anterior to posterior direction, the levels of Amlac2 transcript increase earlier in the thoracic than in the abdominal integument. The gene expression lasts even after the bees emerge from brood cells and begin activities in the nest, but declines after the transition to foraging stage, suggesting that maturation of the exoskeleton is completed at this stage. Post-transcriptional knockdown of Amlac2 gene expression resulted in structural abnormalities in the exoskeleton and drastically affected adult eclosion. By setting a ligature between the thorax and abdomen of early pupae we could delay the increase in hemolymph ecdysteroid levels in the abdomen. This severely impaired the increase in Amlac2 transcript levels and also the differentiation of the abdominal exoskeleton. Taken together, these results indicate that Amlac2 expression is controlled by ecdysteroids and has a critical role in the differentiation of the adult exoskeleton of honey bees. (C) 2010 Elsevier Ltd. All rights reserved.
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In [Haiyin Gao, Ke Wang, Fengying Wei, Xiaohua Ding, Massera-type theorem and asymptotically periodic Logistic equations, Nonlinear Analysis: Real World Applications 7 (2006) 1268-1283, Lemma 2.1] it is established that a scalar S-asymptotically to-periodic function (that is, a continuous and bounded function f : [0, infinity) -> R such that lim(t ->infinity)(f (t + omega) - f (t)) = 0) is asymptotically omega-periodic. In this note we give two examples to show that this assertion is false. (C) 2008 Elsevier Ltd. Ail rights reserved.
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A bounded continuous function it u : [0, infinity) -> X is said to be S-asymptotically omega-periodic if lim(t ->infinity)[u(t + omega) - u(t)] = 0. This paper is devoted to study the existence and qualitative properties of S-asymptotically omega-periodic mild solutions for some classes of abstract neutral functional differential equations with infinite delay, Furthermore, applications to partial differential equations are given.
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By using the theory of semigroups of growth a, we discuss the existence of mild solutions for a class of abstract neutral functional differential equations. A concrete application to partial neutral functional differential equations is considered. (C) 2011 Elsevier Ltd. All rights reserved.
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Previous studies have reported differences in presenting symptoms and angiographic characteristics between women and men undergoing evaluation for suspected coronary artery disease (CAD). We examined the relation between symptoms and extent of CAD in patients with type 2 diabetes mellitus and known CAD enrolled in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial. Of 1,775 patients (533 women, 30%, and 1,242 men, 70%), women were more likely than men to have angina (65% vs 56%, p < 0.001) or an atypical angina/anginal equivalent (71% vs 58%, p < 0.001). More women reported unstable angina (17% vs 13%, p = 0.047) or were in a higher Canadian Cardiology Society class compared to men (Canadian Cardiology Society classes II to IV 78% vs 68%, p = 0.002). Fewer women than men had no symptoms (14% vs 22%, p < 0.001). Women had a lower mean myocardial jeopardy index (42.5 +/- 24.3 vs 47.9 +/- 24.3, p < 0.001), smaller number of total significant lesions (2.3 +/- 17 1.7 vs 2.7 +/- 1.8, p < 0.001), and fewer jeopardized left ventricular regions (p < 0.001 for distribution) or long-term occlusions (29% vs 42%, p < 0.001). After adjustment for relevant covariates, the odds of having CAD symptoms were still higher in women than men (odds ratio for angina 1.31, 95% confidence interval 1.02 to 1.69; odds ratio for atypical angina 1.52, 95% confidence interval 1.17 to 1.96). In conclusion, in a high-risk group of patients with known CAD and diabetes mellitus, women were more symptomatic than men but had less obstructive CAD. These data suggest that factors other than epicardial CAD severity influence symptom presentation in women in this population. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;107:980-985)
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Background-In the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial, an initial strategy of coronary revascularization and optimal medical treatment (REV) compared with an initial optimal medical treatment with the option of subsequent revascularization (MED) did not reduce all-cause mortality or the composite of cardiovascular death, myocardial infarction, and stroke in patients with type 2 diabetes mellitus and stable ischemic heart disease. In the same population, we tested whether the REV strategy was superior to the MED strategy in preventing worsening and new angina and subsequent coronary revascularizations. Methods and Results-Among the 2364 men and women (mean age, 62.4 years) with type 2 diabetes mellitus, documented coronary artery disease, and myocardial ischemia, 1191 were randomized to the MED and 1173 to the REV strategy preselected in the percutaneous coronary intervention (796) and coronary artery bypass graft (377) strata. Compared with the MED strategy, the REV strategy at the 3-year follow-up had a lower rate of worsening angina (8% versus 13%; P < 0.001), new angina (37% versus 51%; P = 0.001), and subsequent coronary revascularizations (18% versus 33%; P < 0.001) and a higher rate of angina-free status (66% versus 58%; P = 0.003). The coronary artery bypass graft stratum patients were at higher risk than those in the percutaneous coronary intervention stratum, and had the greatest benefits from REV. Conclusions-In these patients, the REV strategy reduced the occurrence of worsening angina, new angina, and subsequent coronary revascularizations more than the MED strategy. The symptomatic benefits were observed particularly for high-risk patients.
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One hundred forty-two women with polycystic ovary syndrome (PCOS) with an average body mass index (BMI) of 29.1 kg/m(2) and average age of 25.12 years were studied. By BMI, 30.2% were normal, 38.0% were overweight and 31.6% were obese. Thirty-one eumenorrheic women matched for BMI and age, with no evidence of hyperandrogenism, were recruited as controls. The incidence of dyslipidemia in the PCOS group was twice that of the Control group (76.1% versus 32.25%). The most frequent abnormalities were low high-density lipoprotein cholesterol (HDL-C; 57.6%) and high triglyceride (TG) (28.3%). HDL-C was significantly lower in all subgroups of women with PCOS when compared to the subgroups of normal women. No significant differences were seen in the total cholesterol (p = 0.307), low-density lipoprotein cholesterol (LDL-C; p = 0.283) and TGs (p = 0.113) levels among the subgroups. An independent effect on HDL-C was detected for glucose (p = 0.004) and fasting insulin (p = 0.01); on TG for age (p = 0.003) and homeostatic model assessment insulin resistance (p = 0.03) and on total cholesterol and LDL-C for age (p = 0.02 and p = 0.033, respectively). In conclusion, dyslipidemia is common in women with PCOS, mainly due to low HDL-C levels. BMI has a significant impact on this abnormality.
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Objective: To clarify whether the metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein (HDL) are altered in patients with polycystic ovary syndrome (PCOS). Design: Case control study. Setting: Endocrinology clinics. Patient(s): Eight normal-weight (NW) and 15 obese (013) patients with PCOS were compared with 10 NW and 10 Ob women without PCOS paired for age and body mass index. Intervention(s): Determination of triglyceride-rich lipoprotein metabolism and lipid transfer to HDL. Main Outcome Measure(s): Participants were injected triglyceride-rich emulsions labeled with (14)C-cholesteryl esters and (3)H-triglycerides and the fractional clearance rate (FCR, in min(-1)) of labels was determined. Lipid transfer from artificial nanoemulsions to HDL was performed by incubating radioactively labeled lipid nanoemulsions with plasma during 1 hour, followed by radioactive counting of HDL-containing supernatant after chemical precipitation. Result(s): Lipolysis estimated by triglyceride FCR was equal in PCOS groups (NW = 0.043 +/- 0.032, Ob = 0.033 +/- 0.009) and respective controls (NW = 0.039 +/- 0.015, Ob = 0.044 +/- 0.019). However, the remnant removal as estimated by cholesteryl ester FCR was reduced in both PCOS groups (NW = 0.005 +/- 0.006, Ob = 0.005 +/- 0.005) compared with controls (NW = 0.016 +/- 0.006, Ob = 0.011 +/- 0.072). Lipid transfer rates were not different among groups, but triglyceride transfer rates were positively correlated with homeostasis model assessment estimate of insulin resistance in PCOS. Conclusion(s): PCOS patients showed decreased removal of atherogenic remnants even when fasting glucose was <100 mg/dL. This reinforces the usefulness of the measures taken to prevent cardiovascular events in PCOS patients. (Fertil Steril (R) 2010;93:1948-56. (C)2010 by American Society for Reproductive Medicine.)
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Background: People with less education in Europe, Asia, and the United States are at higher risk of mortality associated with daily and longer-term air pollution exposure. We examined whether educational level modified associations between mortality and ambient particulate pollution (PM(10)) in Latin America, using several timescales. Methods: The study population included people who died during 1998-2002 in Mexico City, Mexico; Santiago, Chile; and Sao Paulo, Brazil. We fit city-specific robust Poisson regressions to daily deaths for nonexternal-cause mortality, and then stratified by age, sex, and educational attainment among adults older than age 21 years (none, some primary, some secondary, and high school degree or more). Predictor variables included a natural spline for temporal trend, linear PM(10) and apparent temperature at matching lags, and day-of-week indicators. We evaluated PM(10) for lags 0 and I day, and fit an unconstrained distributed lag model for cumulative 6-day effects. Results: The effects of a 10-mu g/m(3) increment in lag 1 PM(10) on all nonextemal-cause adult mortality were for Mexico City 0.39% (95% confidence interval = 0.131/-0.65%); Sao Paulo 1.04% (0.71%-1.38%); and for Santiago 0.61% (0.40%-0.83%. We found cumulative 6-day effects for adult mortality in Santiago (0.86% [0.48%-1.23%]) and Sao Paulo (1.38% [0.85%-1.91%]), but no consistent gradients by educational status. Conclusions: PM(10) had important short- and intermediate-term effects on mortality in these Latin American cities, but associations did not differ consistently by educational level.
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Background Factors affecting vulnerability to heat-related mortality are not well understood. Identifying susceptible populations is of particular importance given anticipated rising temperatures from climatic change. Methods We investigated heat-related mortality for three Latin American cities (Mexico City, Mexico; Sao Paulo, Brazil; Santiago, Chile) using a case-crossover approach for 754 291 deaths from 1998 to 2002. We considered lagged exposures, confounding by air pollution, cause of death and susceptibilities by educational attainment, age and sex. Results Same and previous day apparent temperature were most strongly associated with mortality risk. Effect estimates remained positive though lowered after adjustment for ozone or PM(10). Susceptibility increased with age in all cities. The increase in mortality risk for those >= 65 comparing the 95th and 75th percentiles of same-day apparent temperature was 2.69% (95% CI: -2.06 to 7.88%) for Santiago, 6.51% (95% CI: 3.57-9.52%) for Sao Paulo and 3.22% (95% CI: 0.93-5.57%) for Mexico City. Patterns of vulnerability by education and sex differed across communities. Effect estimates were higher for women than men in Mexico City, and higher for men elsewhere, although results by sex were not appreciably different for any city. In Sao Paulo, those with less education were more susceptible, whereas no distinct patterns by education were observed in the other cities. Conclusions Elevated temperatures are associated with mortality risk in these Latin American cities, with the strongest associations in So Paulo, the hottest city. The elderly are an important population for targeted prevention measures, but vulnerability by sex and education differed by city.
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Spinal involvement is a common presentation of multiple myeloma (MM); however, the cervical spine is the least common site of myelomatous involvement. Few studies evaluate the results of percutaneous vertebroplasty (PV) in the treatment of MM of the spine. The purpose of this series is to report on the use of PV in the treatment of MM of the cervical spine and to review the literature. From January 1994 to October 2007, four patients (three men and one woman; mean age, 45 years) who underwent five PV for painful MM in the cervical spine were retrospectively reviewed. The pain was estimated by the patient on a verbal analogic scale. Clinical follow-up was available for all patients (mean, 27.5 months; range, 1-96 months). The mean volume of cement injected per vertebral body was 2.3 +/- 0.8 mL (range, 1.0-4.0 mL) with a mean vertebral filling of 55.0 +/- 12.0% (range, 40.0-75.0%). Analgesic efficacy was achieved in all patients. One patient had a spinal instability due to a progression of spinal deformity noted on follow-up radiographs, without clinical symptoms. Cement leakage was detected in three (60%) of the five treated vertebrae. There was no clinical complication. The present series suggests that PV for MM of the cervical spine is safe and effective for pain control; nonetheless, the detrimental impact of the disease on bone quality should prompt close radiological follow-up after PV owing to the risk of spinal instability.
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BACKGROUND CONTEXT: The vertebral spine angle in the frontal plane is an important parameter in the assessment of scoliosis and may be obtained from panoramic X-ray images. Technological advances have allowed for an increased use of digital X-ray images in clinical practice. PURPOSE: In this context, the objective of this study is to assess the reliability of computer-assisted Cobb angle measurements taken from digital X-ray images. STUDY DESIGN/SETTING: Clinical investigation quantifying scoliotic deformity with Cobb method to evaluate the intra- and interobserver variability using manual and digital techniques. PATIENT SAMPLE: Forty-nine patients diagnosed with idiopathic scoliosis were chosen based on convenience, without predilection for gender, age, type, location, or magnitude of the curvature. OUTCOME MEASURES: Images were examined to evaluate Cobb angle variability, end plate selection, as well as intra- and interobserver errors. METHODS: Specific software was developed to digitally reproduce the Cobb method and calculate semiautomatically the degree of scoliotic deformity. During the study, three observers estimated the Cobb angle using both the digital and the traditional manual methods. RESULTS: The results showed that Cobb angle measurements may be reproduced in the computer as reliably as with the traditional manual method, in similar conditions to those found in clinical practice. CONCLUSIONS: The computer-assisted method (digital method) is clinically advantageous and appropriate to assess the scoliotic curvature in the frontal plane using Cobb method. (C) 2010 Elsevier Inc. All rights reserved.