950 resultados para Heat storage rate


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Mice expressing human cholesteryl ester transfer protein (huCETP) are more resistant to Escherichia coli bacterial wall LIPS because death rates 5 days after intraperitoneal inoculation of LIPS were higher in wild-type than in huCETP(+/-) mice, whereas all huCETP(+/+) mice remained alive. After LIPS inoculation, plasma concentrations of TNF-alpha and IL-6 increased less in huCETP(+/+) than in wild-type mice. LPS in vitro elicited lower TNF-alpha production by CETP expressing than by wild-type macrophages. In addition, TNF-alpha production by RAW 264.7 murine macrophages increased on incubation with LPS but decreased in a dose-dependent manner when human CETP was added to the medium. Human CETP in vitro enhanced the LIPS binding to plasma high-density lipoprotein/low-density lipoprotein. The liver uptake of intravenous infused C-14-LPS from Salmonella typhimurium was greater in huCETP(+/+) than in wild-type mice. Present data indicate for the first time that CETP is an endogenous component involved in the first line of defense against an exacerbated production of proinflammatory mediators.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Many questions remain unanswered about premature atherosclerosis in rheumatoid arthritis (RA). Besides inflammation, some studies have suggested the role of autoantibodies on its pathogenesis. Objective: The aim of this study was to investigate the presence of antibodies against phospholipids, beta2-glycoproteinl (beta2-gpl), lipoprotein lipase, and heat shock proteins (Hsp) in RA patients and to evaluate their possible association with subclinical carotid atherosclerosis. Methods: Seventy-one RA patients and 53 age- and sex-matched controls were selected to perform anticardiolipin antibodies (aCL) (IgG and IgM), anti-beta2-gpl (IgG, IgM, and IgA), anti-lipoprotein lipase (anti-LPL), anti-Hsp 60, and anti-Hsp 65 by ELISA tests. Intima-medial thickness (IMT) of common carotid and presence of plaques were assessed by high-resolution B-mode ultrasonography. Exclusion criteria were smoking, diabetes, and arterial hypertension. Lipoproteins, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and fibrinogen levels, as well as health assessment questionnaire (HAQ) and disease activity score (DAS) 28 were also evaluated. Results: Age (48.93 +/- 12.31 vs. 45.37 +/- 9.37 years; p = 0.20) and body mass index (BMI) (p = 0.69) were similar in RA and controls, as well as female gender (p = 0.56). The mean IMT was similar between RA and controls (0. 721 +/- 0.16 vs. 0.667 +/- 0.14 turn, p = 0.07) but the frequency of plaques was higher in RA (14.1% vs. 1.9%; p = 0.02). In RA patients, IMT measurements did not differ according to the presence or absence of these antibodies: IgG aCL (0.62 +/- 0.64 vs. 0.72 +/- 0.17 mm, p = 0.24), IgM aCL (0.65 +/- 0.79 vs. 0.73 +/- 0.17 mm, p = 0.33), anti-Hsp 60 (0.78 +/- 0.20 vs. 0.71 +/- 0.16 mm, p = 0.27), anti-Hsp 65 (0.73 +/- 0.16 vs. 0.72 +/- 0.17 mm, p = 0.77), IgG anti-beta2-gpl (0.73 +/- 0.16 vs. 0.71 +/- 0.17 mm, p = 0.72), and anti-CCP (0.71 +/- 0.16 vs. 0.76 +/- 0.20 mm, p = 0.36). In addition, IMT did not correlate with antibodies titers: IgG aCL (r = -0.09, p = 0.47), IgM aCL (r = - 0.15, p = 0.21), anti-Hsp 60 (r = 0.10, p = 0.42), anti-Hsp 65 (r = 0.05, p = 0.69), IgG anti-beta2-gpl (r = - 0.07, p = 0.57), IgM anti-beta2-gpl (r = - 0.05, p = 0.69), IgA anti-beta2-gpl (r = 0.03, p = 0.79), and anti-CCP (r = - 0.07, p = 0.57). RA patients with plaques had a significantly higher age compared to those without plaques (p = 0.001), as well as higher mean IMT (p < 0.001), total cholesterol (p = 0.001), and LDL (p = 0.003). Conclusions: In RA a clear association between all autoantibodies studied herein and increased IMT or presence of plaques was not observed. The great prevalence of carotid atherosclerosis in RA was related to age, total and LDL cholesterol, as identified in normal population. (c) 2008 Elsevier Masson SAS. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We aimed to investigate whether creatine supplementation affects the measured glomerular filtration rate in postmenopausal women (age, 58 +/- 3 years). Subjects were randomly assigned to receive either creatine (20 g(.)day(-1) for 1 week and 5 g(.)day(-1) thereafter) or a placebo. Kidney function was assessed at baseline and after 12 weeks. [(51)Cr] EDTA clearance remained unchanged (CR-PRE: 86.16 +/- 14.36 mL(.)min(-1) per 1.73 m(2), POST: 87.25 +/- 17.60 mL(.)min(-1) per 1.73 m(2); PL-PRE: 85.15 +/- 8.54 mL(.)min(-1) per 1.73 m(2), POST: 87.18 +/- 9.64 mL(.)min(-1) per 1.73 m(2); p = 0.81). Thus, we concluded that creatine supplementation does not affect glomerular filtration rate in postmenopausal women.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abnormal heart-rate (HR) response during or after a graded exercise test has been recognized as a strong and an independent predictor of all-cause mortality in healthy and diseased subjects. The purpose of the present study was to evaluate the HR response during exercise in women with systemic lupus erythematosus (SLE). In this case-control study, 22 women with SLE (age 29.5 perpendicular to 1.1 years) were compared with 20 gender-, BMI-, and age-matched healthy subjects (age 26.5 +/- 1.4 years). A treadmill cardiorespiratory test was performed and HR response during exercise was evaluated by the chronotropic reserve (CR). HR recovery (Delta HRR) was defined as the difference between HR at peak exercise and at both first (Delta HRR1) and second (Delta HRR2) minutes after exercising. SLE patients presented lower peak VO(2) when compared with healthy subjects (27.6 perpendicular to 0.9 vs. 36.7 perpendicular to 1.1 ml/kg/min, p = 0.001, respectively). Additionally, SLE patients demonstrated lower CR (71.8 +/- 2.4 vs. 98.2 +/- 2.6%, p = 0.001), Delta HRR1 (22.1 +/- 2.5 vs. 32.4 +/- 2.2%, p = 0.004) and Delta HRR2 (39.1 +/- 2.9 vs. 50.8 +/- 2.5%, p = 0.001) than their healthy peers. In conclusion, SLE patients presented abnormal HR response to exercise, characterized by chronotropic incompetence and delayed Delta HRR. Lupus (2011) 20, 717-720.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The syntheses and characterisation of the new macrocyclic hexaamine trans-(5(S),7(S),12(R),14(R)-tetramethyl)-1,4,8,11-tetraazacyclotetradecane-6,13-diamine (L-6) and its Co-III complex are reported. The X-ray crystal structural analyses of [CoL6]Cl-2(ClO4) [monoclinic, space group C2/c, a = 16.468(3) Angstrom, b = 9.7156(7) Angstrom, c = 15.070(3) Angstrom, beta = 119.431(8)degrees, Z = 4] and the closely related cis-diamino-substituted macrocyclic complex [CoL2](ClO4)(3) . 2H(2)O (L-2 = cis-6,13-dimethyl-1,4,8,11-tetraazacyclotetradecane-6,13-diamine) [orthorhombic, space group Pna2(1), a = 16.8220(8) Angstrom, b = 10.416(2) Angstrom, c = 14.219(3) Angstrom, Z = 4] reveal significant variations in the observed Co-N bond lengths and coordination geometries, which may be attributed to the trans or cis disposition of the pendent primary amines. The Co-III/II self-exchange electron transfer rate constants for these and other closely related hexaamines have been determined, and variations of some 2 orders of magnitude are found between pairs of trans and cis isomeric Co-III complexes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction. The quality and effectiveness of myocardial protection are fundamental problems to expand the use of and consequently good outcomes of donated hearts for transplantation. Objective. The purpose of this investigation was to compare the cardioprotective effects of Krebs-Henseleit, Bretschneider-HTK, St Thomas, and Celsior solutions using a modified nonrecirculating Langendorff column model of isolated perfused rat heart during prolonged cold storage. Materials and Methods. After removal 36 rat hearts underwent isolated perfusion into a Langendorff apparatus using Krebs-Henseleit solution for a 15-minute period of recovery; we excluded organs that did not maintain an aortic pressure above 100 m Hg. Subsequently, we equally distributed the hearts into four groups according to the cardioprotection solution; group 1, Krebs-Henseleit (control); group II, Bretschneider-HTK; group III, St Thomas; and group IV, Celsior. Each heart received the specific cardioplegic solution at 10 C for 2-hour storage at 20 C, before a 15 minutes perfusion with Krebs-Henseleit solution for recovery and stabilization. After 60 additional minutes of perfusion, every 5 minutes we determined heart rate (HR), coronary flow (CF), left ventricular systolic pressure (LVSP), and positive and negative peak of the first derivative of left ventricular pressure (+dP/dt and dP/dt, respectively). Results. Comparative analysis by Turkey`s test showed the following performances among the groups at 60 minutes of reperfusion: HR: II = IV > III > I; CF: II = IV > I = III; LVSP: IV > I = II = III; +dP/dt: IV > I = II = III; and dP/dt: IV = II > I = II. Conclusion. Cardioprotective solutions generally used in clinical practice are not able to avoid hemodynamic alterations in hearts exposed to prolonged ischemia. Celsior solution showed better performance than Bretschneider-HTK, St Thomas, and Krebs-Henseleit.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Color Doppler myocardial imaging (CDMI) allows the calculation of local longitudinal or radial strain rate (SR) and strain (epsilon). The aims of this study were to determine the feasibility and reproducibility of longitudinal and radial SR and epsilon in neonates during the first hours of life and to establish reference values. Methods: Data were obtained from 55 healthy neonates (29 male; mean age, 20 +/- 14 hours; mean birth weight, 3,174 +/- 374 g). Apical and parasternal views quantified regional longitudinal and radial SR and epsilon in differing ventricular wall segments. Values at peak systole, early diastole, and late diastole were calculated from the extracted curves. CDMI data acquired at 300 +/- 50 frames/s were analyzed offline. Three consecutive cardiac cycles were measured during normal respiration. The timing of specific systolic or diastolic regional events was determined. Multiple comparisons between walls and segments were made. Results: Left ventricular (LV) longitudinal deformation showed basal differences compared with apical segments within one specific wall. Right ventricular (RV) longitudinal deformation was not homogeneous, with significant differences between basal and apical segments. Longitudinal 3 values were higher in the RV free basal and middle wall segments compared with the left ventricle. In the RV free wall apical segment, longitudinal SR and 3 were maximal. LV systolic SR and epsilon values were higher radially compared with longitudinally (radial peak systolic SR midportion, 2.9 +/- 0.6 s(-1); radial peak systolic epsilon 53.8 +/- 19%; longitudinal peak systolic SR midportion, -1.8 +/- 0.5 s(-1); longitudinal peak systolic epsilon, -24.8 +/- 3%; P < .01). Longitudinal systolic epsilon and SR interobserver variability values were 1.2% and 0.7%, respectively. Conclusion: Ultrasound-based SR and 3 imaging is a practical and reproducible clinical technique in neonates, allowing the calculation of regional longitudinal and radial deformation in RV and LV segments. These regional SR and epsilon indices represent new, noninvasive parameters that can quantify normal neonate regional cardiac function. Independent from visual interpretation, they can be used as reference values for diagnosis in ill neonates. (J Am Soc Echocardiogr 2009;22:369-375.)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chinese-style dried, shredded meat is traditionally prepared by sequential cooking, shredding, pre-drying, and final drying (roasting) of lean meat. In this study, shredded dried beef (a(w)<0.6) was prepared by omitting roasting but prolonging pre-drying. Sensory scores of the modified product were lower than those for the traditional product. When heat pump drying replaced traditional oven drying, drying time was shortened without significant difference in quality attributes. Desorption curves were established for shredded beef at several drying temperatures.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective To determine accuracy of first trimester detection of single umbilical artery (SUA). Methods The number of vessels in the umbilical cord was examined in a prospective cohort of 779 singleton, low-risk, unselected pregnancies, in the first (11-13 weeks) and second (17-24 weeks) trimesters, using both power and color Doppler and after delivery, by placental histopathologic exam. Concordance between first and second trimester findings to postnatal diagnoses was compared by calculating kappa coefficients. Results There was medium concordance between the findings in the first trimester and the postnatal diagnoses (kappa = 0.52) and high concordance (kappa = 0.89) for the second trimester scan. Sensitivity, specificity, positive and negative predictive values for the findings in the first trimester were 57.1, 98.9, 50.0 and 99.2% and for the second trimester were 86.6, 99.9, 92.9 and 99.7%. Conclusion Sensitivity and positive predictive value of first trimester scan to identify an isolated SUA in a prospective unselected population was poor. Diagnosis of isolated SUA as well as a definitive judgment about the presence of associated anomalies would still require a scan in the second trimester. Copyright (C) 2011 John Wiley & Sons, Ltd.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Although cigarette smoking and alcohol consumption increase risk for head and neck cancers, there have been few attempts to model risks quantitatively and to formally evaluate cancer site-specific risks. The authors pooled data from 15 case-control studies and modeled the excess odds ratio (EOR) to assess risk by total exposure (pack-years and drink-years) and its modification by exposure rate (cigarettes/day and drinks/day). The smoking analysis included 1,761 laryngeal, 2,453 pharyngeal, and 1,990 oral cavity cancers, and the alcohol analysis included 2,551 laryngeal, 3,693 pharyngeal, and 3,116 oval cavity cancers, with over 8,000 controls. Above 15 cigarettes/day, the EOR/pack-year decreased with increasing cigarettes/day, suggesting that greater cigarettes/day for a shorter duration was less deleterious than fewer cigarettes/day for a longer duration. Estimates of EOR/pack-year were homogeneous across sites, while the effects of cigarettes/day varied, indicating that the greater laryngeal cancer risk derived from differential cigarettes/day effects and not pack-years. EOR/drink-year estimates increased through 10 drinks/day, suggesting that greater drinks/day for a shorter duration was more deleterious than fewer drinks/day for a longer duration. Above 10 drinks/day, data were limited. EOR/drink-year estimates varied by site, while drinks/day effects were homogeneous, indicating that the greater pharyngeal/oral cavity cancer risk with alcohol consumption derived from the differential effects of drink-years and not drinks/day.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background This study describes heat- and cold-related mortality in 12 urban populations in low- and middle-income countries, thereby extending knowledge of how diverse populations, in non-OECD countries, respond to temperature extremes. Methods The cities were: Delhi, Monterrey, Mexico City, Chiang Mai, Bangkok, Salvador, So Paulo, Santiago, Cape Town, Ljubljana, Bucharest and Sofia. For each city, daily mortality was examined in relation to ambient temperature using autoregressive Poisson models (2- to 5-year series) adjusted for season, relative humidity, air pollution, day of week and public holidays. Results Most cities showed a U-shaped temperature-mortality relationship, with clear evidence of increasing death rates at colder temperatures in all cities except Ljubljana, Salvador and Delhi and with increasing heat in all cities except Chiang Mai and Cape Town. Estimates of the temperature threshold below which cold-related mortality began to increase ranged from 15 degrees C to 29 degrees C; the threshold for heat-related deaths ranged from 16 degrees C to 31C. Heat thresholds were generally higher in cities with warmer climates, while cold thresholds were unrelated to climate. Conclusions Urban populations, in diverse geographic settings, experience increases in mortality due to both high and low temperatures. The effects of heat and cold vary depending on climate and non-climate factors such as the population disease profile and age structure. Although such populations will undergo some adaptation to increasing temperatures, many are likely to have substantial vulnerability to climate change. Additional research is needed to elucidate vulnerability within populations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

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.