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1.
Toxicology ; 443: 152547, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32755643

RESUMO

Traditional methods for cancer risk assessment are retrospective, resource-intensive, and not feasible for the vast majority of environmental chemicals. In earlier studies, we used a set of six biomarkers to accurately identify liver tumorigens in transcript profiles derived from chemically-treated rats using either a Toxicological Priority Index (ToxPi) approach or using derived biomarker thresholds for cancer. The biomarkers consisting of 7-113 genes are used to predict the most common liver cancer molecular initiating events: genotoxicity, cytotoxicity and activation of the xenobiotic receptors AhR, CAR, ER, and PPARα. In the present study, we apply and evaluate the performance of these methods for cancer prediction in an independent rat liver study of 44 chemicals (6 h-7d exposures) examined by Affymetrix arrays. In the first approach, ToxPi ranking of biomarker scores consistently gave the highest scores to tumorigenic chemical-dose pairs; balanced accuracies for identification of liver tumorigenic chemicals were up to 89 %. The second approach used tumorigenic thresholds derived in the present study or from our earlier study that were set at the maximum value for chemical-dose exposures without detectable liver tumor outcomes. Using these thresholds, balanced accuracies were up to 90 %. Both approaches identified all tumorigenic chemicals. Almost all of the tumorigenic chemicals activated more than one MIE. We also compared biomarker responses between two types of profiling platforms (Affymetrix full-genome array, TempO-Seq 1500+ array containing ∼2600 genes) and found that the lack of the full set of biomarker genes on the 1500+ array resulted in decreased ability to identify chemicals that activate the MIEs. Overall, these results demonstrate that predictive approaches based on the 6 biomarkers could be used in short-term assays to identify chemicals and their doses that induce liver tumors, the most common endpoint in rodent bioassays.


Assuntos
Biomarcadores Tumorais/genética , Carcinógenos/toxicidade , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Animais , Bioensaio , Expressão Gênica , Masculino , Ratos Sprague-Dawley
2.
J Strength Cond Res ; 29(2): 408-15, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24513619

RESUMO

The purposes of this study were to: (a) examine the age-related patterns of differences in height (HT), body mass (BM), percent body fat (% fat), body mass index (BMI), and skinfolds (SF) in 11- to 18-year-old wrestlers; (b) determine the coherence of direct (% fat) and indirect (BMI and SFs) indicators of adiposity in the wrestlers; and (c) compare the age-related patterns and mean values for HT, BM, BMI, subscapular, and triceps SF for the wrestlers to those of national samples of boys from the National Health and Nutrition Examination Survey (NHANES) database. One hundred thirty wrestlers were divided into 8 independent yearly age groups (AG): AG11-AG18 years. Height, BM, BMI, subscapular SF, triceps SF, medial calf SF, thigh SF, sum of SFs, and % fat were assessed. There were no differences between the wrestlers and NHANES samples for age-related patterns of BMI (0.61 and 0.63 kg·m·y), subscapular SF (0.47 and 0.37 mm·y), or triceps SF (-0.31 and -0.39 mm·y). Furthermore, the wrestlers displayed no differences in % fat between age groups. The results indicated that: (a) dissociations existed between the direct and indirect indicators of adiposity; (b) the wrestlers were similar in height but had smaller upper-body SFs when compared with NHANES samples; and (c) participation in wrestling (1-8 years) had no adverse effects on the normal age-related growth patterns for HT, but favorable effects on measures of adiposity.


Assuntos
Adiposidade , Luta Romana/fisiologia , Adolescente , Fatores Etários , Estatura , Índice de Massa Corporal , Criança , Estudos Transversais , Humanos , Masculino , Inquéritos Nutricionais , Pregas Cutâneas
3.
Sens Actuators B Chem ; 190: 634-644, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25246730

RESUMO

Microfluidic platforms provide several advantages for liquid-liquid extraction (LLE) processes over conventional methods, for example with respect to lower consumption of solvents and enhanced extraction efficiencies due to the inherent shorter diffusional distances. Here, we report the development of polymer-based parallel-flow microfluidic platforms for LLE. To date, parallel-flow microfluidic platforms have predominantly been made out of silicon or glass due to their compatibility with most organic solvents used for LLE. Fabrication of silicon and glass-based LLE platforms typically requires extensive use of photolithography, plasma or laser-based etching, high temperature (anodic) bonding, and/or wet etching with KOH or HF solutions. In contrast, polymeric microfluidic platforms can be fabricated using less involved processes, typically photolithography in combination with replica molding, hot embossing, and/or bonding at much lower temperatures. Here we report the fabrication and testing of microfluidic LLE platforms comprised of thiolene or a perfluoropolyether-based material, SIFEL, where the choice of materials was mainly guided by the need for solvent compatibility and fabrication amenability. Suitable designs for polymer-based LLE platforms that maximize extraction efficiencies within the constraints of the fabrication methods and feasible operational conditions were obtained using analytical modeling. To optimize the performance of the polymer-based LLE platforms, we systematically studied the effect of surface functionalization and of microstructures on the stability of the liquid-liquid interface and on the ability to separate the phases. As demonstrative examples, we report (i) a thiolene-based platform to determine the lipophilicity of caffeine, and (ii) a SIFEL-based platform to extract radioactive copper from an acidic aqueous solution.

4.
J Strength Cond Res ; 28(8): 2154-63, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24513614

RESUMO

Twenty-one men (mean ± SD; age = 23.5 ± 2.6 years, BMI = 26.0 ± 2.4 kg-1·m-2) completed this randomized, double-blinded, placebo-controlled, crossover study to examine acute responses to a thermogenic nutritional supplement. Each testing session included: (a) 30 minutes resting, followed by placebo or thermogenic nutritional supplementation, (b) 50 minutes postsupplementation resting, (c) 60 minutes walking, and (d) 50 minutes postexercise recovery. Gas exchange variables and heart rate (HR) were recorded during each phase. Blood pressure was recorded during all phases except exercise. Ratings of perceived exertion (RPE) were recorded only during exercise. There were no significant differences for any of the measures between the supplement and placebo during the initial resting or postsupplementation phases. During exercise, energy expenditure (EE) (placebo = 18.98-19.06 kJ·min-1 and supplement = 19.44-19.82 kJ·min-1) and VO2 (placebo = 11.27-11.35 ml·kg-1·min-1; supplement = 11.64-11.82 ml·kg-1·min-1) were greater for the supplement than placebo. There were no differences in respiratory exchange ratio (RER), HR, or RPE between the supplement and placebo during exercise. Postexercise, only VO2 (placebo = 3.53-3.63 ml·kg-1·min-1; supplement = 3.71-3.84 ml·kg-1·min-1) was greater for the supplement than placebo, but there were no differences in EE, RER, HR, or blood pressure. These findings suggested that the specific blend of ingredients in the thermogenic nutritional supplement, when combined with exercise, increased the metabolic rate with minimal changes in cardiovascular function and no effect on RPE.


Assuntos
Suplementos Nutricionais , Descanso/fisiologia , Caminhada/fisiologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Esforço Físico/efeitos dos fármacos , Esforço Físico/fisiologia , Troca Gasosa Pulmonar/efeitos dos fármacos , Troca Gasosa Pulmonar/fisiologia , Termogênese , Adulto Jovem
5.
Eur J Pharmacol ; 728: 161-6, 2014 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-24509134

RESUMO

The purpose of this study was to examine the effects of anatabine supplementation in conjunction with unilateral, maximal eccentric isokinetic muscle actions on serum markers of muscle damage and pro-inflammatory cytokines in humans. Seventeen men (mean ± S.D. age = 22.4 ± 3.2 yrs) participated in this double-blinded, placebo-controlled, crossover study. Participants were randomly assigned to two 10-day conditions (anatabine and placebo) separated by a 2-4 week washout period. After seven days of supplementation, blood was sampled immediately prior to PRE, immediately following POST, and 24, 48, and 72 h after 6 sets of 10 repetitions of unilateral, maximal eccentric isokinetic forearm flexion exercise. Concentrations of serum creatine kinase, lactate dehydrogenase, myoglobin, high sensitivity c-reactive protein, and TNF-α were measured. Creatine kinase, myoglobin, and lactate dehydrogenase increased (P<0.05), while high sensitivity c-reactive protein and TNF-α did not change (P>0.05) after the eccentric exercise during both conditions. Lactate dehydrogenase was higher (P<0.05) during the anatabine condition. The primary findings of this study were two-fold: (a) anatabine had no beneficial effects on traditional markers of muscle damage (creatine kinase, lactate dehydrogenase, and myoglobin) compared to placebo after the eccentric exercise protocol, and (b) the eccentric exercise protocol did not elicit increase in the pro-inflammatory cytokines (c-reactive protein and TNF-α). Future studies are needed to examine the effects of anatabine on naturally-occurring inflammation that is common with aging or obesity. Furthermore, additional research is needed to examine the relationship between muscle damage and inflammation after eccentric exercises of different modes, durations, and intensities.


Assuntos
Alcaloides/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Biomarcadores/sangue , Exercício Físico , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/lesões , Piridinas/farmacologia , Adulto , Alcaloides/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Estudos Cross-Over , Citocinas/sangue , Suplementos Nutricionais , Método Duplo-Cego , Exercício Físico/fisiologia , Humanos , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/imunologia , Músculo Esquelético/enzimologia , Músculo Esquelético/imunologia , Piridinas/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
J Strength Cond Res ; 28(3): 592-600, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24566607

RESUMO

Estimates of critical power (CP) and anaerobic work capacity (AWC) from the power output vs. time relationship have been derived from various mathematical models. The purpose of this study was to examine estimates of CP and AWC from the multiple work bout, 2- and 3-parameter models, and those from the 3-minute all-out CP (CP3min) test. Nine college-aged subjects performed a maximal incremental test to determine the peak oxygen consumption rate and the gas exchange threshold. On separate days, each subject completed 4 randomly ordered constant power output rides to exhaustion to estimate CP and AWC from 5 regression models (2 linear, 2 nonlinear, and 1 exponential). During the final visit, CP and AWC were estimated from the CP3min test. The nonlinear 3-parameter (Nonlinear-3) model produced the lowest estimate of CP. The exponential (EXP) model and the CP3min test were not statistically different and produced the highest estimates of CP. Critical power estimated from the Nonlinear-3 model was 14% less than those from the EXP model and the CP3min test and 4-6% less than those from the linear models. Furthermore, the Nonlinear-3 and nonlinear 2-parameter (Nonlinear-2) models produced significantly greater estimates of AWC than did the linear models and CP3min. The current findings suggested that the Nonlinear-3 model may provide estimates of CP and AWC that more accurately reflect the asymptote of the power output vs. time relationship, the demarcation of the heavy and severe exercise intensity domains, and anaerobic capabilities than will the linear models and CP3min test.


Assuntos
Teste de Esforço , Modelos Lineares , Dinâmica não Linear , Resistência Física/fisiologia , Avaliação da Capacidade de Trabalho , Adulto , Limiar Anaeróbio , Feminino , Humanos , Masculino , Consumo de Oxigênio , Troca Gasosa Pulmonar , Adulto Jovem
7.
Physiol Meas ; 34(10): 1253-67, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24021781

RESUMO

This study examined the relationships among the physical working capacity at the fatigue threshold (PWCFT), the power outputs associated with the gas exchange threshold (PGET) and the respiratory compensation point (PRCP), and critical power (CP) to identify possible physiological mechanisms underlying the onset of neuromuscular fatigue. Ten participants (mean ± SD age: 20 ± 1 years) performed a maximal incremental cycle ergometer test to determine the PWCFT, PGET, and PRCP. CP was determined from the 3 min all-out test. The PWCFT (197 ± 55 W), PRCP (212 ± 50 W), and CP (208 ± 63 W) were significantly greater than the PGET (168 ± 40 W), but there were no significant differences among the PWCFT, PRCP, and CP. All thresholds were significantly inter-4 (r = 0.794-0.958). The 17% greater estimates for the PWCFT than PGET were likely related to differences in the physiological mechanisms that underlie these fatigue thresholds, while the non-significant difference and high correlation between the PWCFT and the PRCP suggested that hyperkalemia may underlie both thresholds. Furthermore, it is possible that the 5% lower estimate of the PWCFT than CP could more accurately reflect the demarcation of the heavy from severe exercise intensity domains.


Assuntos
Metabolismo , Fadiga Muscular/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Eletromiografia , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Troca Gasosa Pulmonar , Análise de Regressão , Respiração , Adulto Jovem
8.
Res Q Exerc Sport ; 84(2): 232-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23930549

RESUMO

PURPOSE: Critical power (CP) from the 3-min test was compared to the power outputs associated with thresholds determined from gas exchange parameters that have been used to demarcate the exercise-intensity domains including the respiratory compensation point (RCP), gas exchange threshold (GET), and ventilatory threshold (VT). METHOD: Twenty-eight participants performed an incremental-cycle ergometer test to exhaustion. The VT was determined from the relationship between the ventilatory equivalent for oxygen uptake (VE/VO2) versus VO2 and the GET was determined using the V-slope method (VCO2 vs. VO2). The RCP was identified from the VE-versus-VCO2 relationship. CP was the average power output during the last 30 s of the 3-min all-out test. Linear regression was used to determine the power outputs associated with the RCP, GET, and VT, as well as the VO2 associated with CP. Mean differences among the associated power outputs, percent VO2 peak, and percent peak power output for the GET, VT, RCP, and CP were analyzed using separate one-way repeated-measures analyses of variance. RESULTS: There were no significant differences between CP (187 +/- 47W) and the power output associated with RCP (190 +/- 49W) or between the power outputs associated with GET (139 +/- 37W) and VT (145 +/- 37W). The power outputs associated with GET and VT, however, were significantly less than were those at CP and associated with RCRP. CONCLUSIONS: These findings suggest CP and RCP demarcate the heavy from severe exercise-intensity domain and result from a different mechanism of fatigue than that of GET and VT, possibly hyperkalemia.


Assuntos
Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Esforço Físico/fisiologia , Troca Gasosa Pulmonar/fisiologia , Ventilação Pulmonar/fisiologia , Adulto , Análise de Variância , Ergometria , Feminino , Humanos , Masculino , Análise de Regressão
9.
Appl Physiol Nutr Metab ; 38(9): 988-95, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23905665

RESUMO

This study examined acute physiologic responses to a thermogenic nutritional supplement at rest, during exercise, and during recovery from exercise in women. Twelve women (mean ± SD age, 22.9 ± 3.1 years) were recruited for this randomized, double-blinded, placebo-controlled, crossover study. Each testing session consisted of 4 phases: 30 min of presupplementation resting, followed by the ingestion of the placebo or thermogenic nutritional supplement; 50 min of postsupplementation resting; 60 min of walking (at 3.2-4.8 km·h(-1)); and 50 min of postexercise resting. Energy expenditure (EE), oxygen consumption, respiratory exchange ratio (RER), oxygen (O2) pulse, and heart rate (HR) values were recorded during all 4 phases. Systolic (SBP) and diastolic (DBP) blood pressure were recorded during the rest, postsupplementation, and postexercise recovery phases; ratings of perceived exertion (RPE) were recorded only during exercise. There were no significant differences for EE, oxygen consumption, O2 pulse, HR, SBP, or DBP between the supplement and placebo during the presupplementation resting or postsupplementation phases. The RER, however, was higher with the supplement at 30 min postsupplementation. During exercise, EE and O2 pulse were 3%-6% greater with the supplement than placebo; there were no significant differences in RPE. Postexercise, EE, oxygen consumption, and DBP were 3%-7% greater with the supplement than placebo. These findings suggest that a thermogenic nutritional supplement, when combined with exercise, increases metabolic rate but has no effect on the perception of effort and results in only minimal changes in cardiovascular function.


Assuntos
Estudos Cross-Over , Descanso , Exercício Físico , Feminino , Frequência Cardíaca , Humanos , Consumo de Oxigênio
10.
J Int Soc Sports Nutr ; 10: 33, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23875823

RESUMO

BACKGROUND: Anatabine (ANA), a minor tobacco alkaloid found in the Solanaceae family of plants, may exhibit anti-inflammatory activity, which may be useful to aid in recovery from exercise-induced muscle damage. The purpose of this study, therefore, was to examine the effects of ANA supplementation on the recovery of isometric strength and selected non-invasive indicators of muscle damage. METHODS: A double-blinded, placebo-controlled, crossover design was used to study eighteen men (mean ± SD age = 22.2 ± 3.1 yrs; body mass = 80.3 ± 15.7 kg) who participated in two randomly-ordered conditions separated by a washout period. The ANA condition consisted of consuming 6-12 mg anatabine per day for 10 days, while testing took place during days 7-10. The placebo (PLA) condition was identical except that the PLA supplement contained no ANA. Maximal voluntary isometric peak torque (PT) of the forearm flexors, arm circumference, hanging joint angle, and subjective pain ratings were measured before (PRE), immediately after (POST), and 24, 48, and 72 h after six sets of 10 maximal, eccentric isokinetic forearm flexion muscle actions. Resting heart rate and blood pressure were measured at PRE and 72 h in each condition. RESULTS: For PT, hanging joint angle, arm circumference, and subjective pain ratings, there were no condition x time (p > 0.05) interactions, there were no main effects for condition (p > 0.05), but there were main effects for time (p < 0.001). There were no condition x time (p > 0.05) interactions and no main effects for condition (p > 0.05) or time (p > 0.05) for blood pressure or resting heart rate. CONCLUSIONS: ANA supplementation had no effect on the recovery of muscle strength, hanging joint angle, arm swelling, or subjective pain ratings after a bout of maximal eccentric exercise in the forearm flexors. Therefore, ANA may not be beneficial for those seeking to improve recovery from heavy eccentric exercise. Future studies should examine the effects of ANA on the pro-inflammatory cytokine responses to exercise-induced muscle damage and the chronic low-grade inflammation observed in obese and elderly individuals.

11.
Appl Physiol Nutr Metab ; 38(1): 7-13, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23368822

RESUMO

The purpose of this study was to determine the specific metabolic and neuromuscular responses at critical power (CP) from the 3-min all-out test. Nine men (mean ± SD: aged 23.7 ± 3.3 years) performed an incremental test for the determination of peak oxygen consumption (VO(2peak)) and gas exchange threshold. CP was estimated for each subject from the 3-min all-out test. Oxygen consumption (VO(2)), the ventilation versus carbon dioxide production ratio (V(E)/VCO(2) ratio), electromyographic (EMG) amplitude, and EMG mean power frequency (MPF) were examined during exhaustive rides at CP for each subject. There was no significant difference between the VO(2) at exhaustion (40.6 ± 7.5 mL·kg(-1)·min(-1)) and VO(2peak) (42.9 ± 7.3 mL·kg(-1)·min(-1)). Furthermore, there were significant increases in EMG amplitude and the V(E)/VCO(2) ratio during the exhaustive rides at CP. There was, however, no significant change in EMG MPF over time. Therefore, the current findings indicated that the 3-min all-out test overestimated CP and the demarcation between the heavy- and severe-intensity domains. Specifically, the VO(2), ventilatory, and EMG amplitude responses were consistent with those observed during continuous exercise in the severe exercise intensity domain. It is likely that the ventilatory and EMG amplitude responses were associated with a common mechanism of fatigue that is different from what affects EMG MPF.


Assuntos
Teste de Esforço/métodos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Adulto , Ciclismo/fisiologia , Eletromiografia/métodos , Teste de Esforço/estatística & dados numéricos , Humanos , Masculino , Contração Muscular/fisiologia , Resistência Física/fisiologia , Valores de Referência , Fatores de Tempo , Adulto Jovem
12.
J Sports Sci ; 31(5): 537-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23121405

RESUMO

The purpose of the present study was to examine oxygen consumption rate ([Vdot][Formula: see text]), heart rate (HR), and ratings of perceived exertion (RPE) responses, as well as time to exhaustion (Tlim) values during continuous rides at critical power (CP) determined from the 3-min all-out test. Eighteen participants (mean ± s: 23.6 ± 3.5 years; 72.7 ± 18.2 kg) performed an incremental cycle ergometer test to exhaustion to determine peak oxygen consumption rate ([Vdot][Formula: see text] peak) and HR peak. Critical power was determined from the 3-min all-out test. Metabolic responses ([Vdot][Formula: see text] and heart rate), RPE, and Tlim were recorded during continuous rides to exhaustion at CP. Linear regression and t-tests were used to compare [Vdot][Formula: see text], heart rate, and RPE responses during the continuous rides to exhaustion. The Tlim at CP was 12.5 ± 6.5 min. There were significant increases in [Vdot][Formula: see text], HR, and RPE during the continuous rides at CP and 15 of the 18 participants reached [Vdot][Formula: see text] peak at exhaustion. Therefore, the [Vdot][Formula: see text], heart rate, and RPE responses, as well as the Tlim values in the present study suggested that CP determined from the 3-min all-out test overestimated the "true" CP and was within the severe exercise intensity domain.


Assuntos
Ciclismo/fisiologia , Exercício Físico/fisiologia , Fadiga/etiologia , Frequência Cardíaca , Consumo de Oxigênio , Resistência Física/fisiologia , Esforço Físico/fisiologia , Adulto , Teste de Esforço , Feminino , Humanos , Modelos Lineares , Masculino , Percepção , Adulto Jovem
13.
J Electromyogr Kinesiol ; 23(2): 349-55, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23246164

RESUMO

There are limited data regarding metabolic responses during continuous exhaustive rides at critical power (CP) from the 3-min all-out test. In addition, no previous studies have examined the mechanomyographic (MMG) responses at CP from the 3-min all-out test. Therefore, this study examined the metabolic and MMG responses during continuous exercise at CP determined from the 3-min all-out test. Nine college-aged females (mean±SD: age 23.0±3.6yrs) performed an incremental test to exhaustion on a cycle ergometer to identify the gas exchange threshold, peak oxygen consumption rate (V˙O2 peak) and heart rate peak (HR peak). The V˙O2, HR, MMG amplitude and mean power frequency (MPF) responses were examined during continuous rides to exhaustion at CP (81±6% peak power). There were significant increases in V˙O2 and HR over time and there was no significant difference between V˙O2 peak and V˙O2 at exhaustion or HR peak and HR at exhaustion. There were, however, no significant changes for MMG amplitude or MPF over time. Therefore, the current findings suggested that the 3-min all-out test overestimated CP and the demarcation between the heavy and severe intensity domains. Specifically, the V˙O2 and HR responses did not reach a steady state and were driven to peak values. Furthermore, the non-significant change in MMG amplitude and MPF were consistent with the responses observed at fatiguing power outputs (i.e., >80% peak power).


Assuntos
Potenciais de Ação/fisiologia , Ergometria/métodos , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Miografia/métodos , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Feminino , Humanos , Perna (Membro)/fisiologia , Adulto Jovem
14.
J Urban Hist ; 38(2): 319-35, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22826892

RESUMO

This article analyzes the renovation and construction of the Parc des Princes and the Stade de France in post-Second World War Paris. The history of the two stadia testifies to a shift in the envisioned role of stadia in the Parisian basin between the late 1960s and the end of the twentieth century and stands as evidence for the emergence of new urban planning actors. Both stadia were also critiqued as symbols of broader problems with Parisian urbanization, notably as manifestations of anti-democratic planning processes. At the same time, the Parc and the Stade also reflected an emerging consensus over the role of spectator sport in society, accompanied by attempts to re-envision mass sporting spectatorship as a more democratic and familial practice. This article thus situates the two stadia within the history of Parisian urbanization and within broader global urbanizing processes.


Assuntos
Planejamento de Cidades , Mudança Social , Simbolismo , População Urbana , Reforma Urbana , Urbanização , Planejamento de Cidades/economia , Planejamento de Cidades/educação , Planejamento de Cidades/história , Planejamento de Cidades/legislação & jurisprudência , História do Século XX , Paris/etnologia , Mudança Social/história , População Urbana/história , Reforma Urbana/economia , Reforma Urbana/educação , Reforma Urbana/história , Reforma Urbana/legislação & jurisprudência , Urbanização/história , Urbanização/legislação & jurisprudência
15.
J Burn Care Res ; 31(1): 93-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20061842

RESUMO

CONTEXT: Necrotizing fasciitis is an aggressive infection affecting the skin and soft tissue. It has a very high acute mortality. The long-term survival and cause of death of patients who survive an index hospitalization for necrotizing fasciitis are not known. OBJECTIVE: To define the long-term survival of patients who survive an index admission for necrotizing fasciitis. We hypothesize that survivors will have a shorter life span than population controls. DESIGN: Long-term follow-up of a registry of patients from 1989 to 2006 who survived a hospitalization for necrotizing fasciitis. Last date of follow-up was January 1, 2008. SETTINGS: A university-based Burn and Trauma Center. PATIENTS: A prospective registry of patients with necrotizing fasciitis has been collected from 1989 to 2006. This registry was linked to data from the Department of Health, Department of Motor Vehicles, and the University Hospital Medical Records Department in January 2008 to obtain follow-up and vital status data. INTERVENTION: None. MAIN OUTCOME MEASURES: Date and cause of death were abstracted from death certificates. Date of last live follow-up was determined from the medical record and by the last driver's license renewal. The death rate of the cohort was standardized for age and sex against 2005 statewide mortality rates. Cause of death was collated into infectious and noninfectious and compared with the statewide causes of death. Statistical analysis included standardized mortality rates, Kaplan-Meier survival curves, and Aalen's additive hazard model. RESULTS: Three hundred forty-five patients of the 377 in the registry survived at least 30 days and were analyzed. Average age at presentation was 49 years (range, 1-86; median, 49). Patients were followed up an average of 3.3 years (range, 0.0-15.7; median, 2.4). Eighty-seven of these patients died (25%). Median survival was 10.0 years (95% confidence interval: 7.25-13.11). There was a trend toward higher mortality in women. Twelve of the 87 deaths were due to infectious causes. Using three different statistical analytic techniques, there was a statistically significant increase in the long-term death rate when compared with population-based controls. Infectious causes of death were statistically higher than controls as well. CONCLUSIONS: Patients who survive an episode of necrotizing fasciitis are at continued risk for premature death; many of these deaths were due to infectious causes such as pneumonia, cholecystitis, urinary tract infections, and sepsis. These patients should be counseled, followed, and immunized to minimize chances of death. Modification of other risk factors for death such as obesity, diabetes, smoking, and atherosclerotic disease should also be undertaken. The sex difference in long-term survival is intriguing and needs to be addressed in further studies.


Assuntos
Fasciite Necrosante/mortalidade , Fasciite Necrosante/terapia , Expectativa de Vida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Unidades de Queimados , Estudos de Casos e Controles , Causas de Morte , Criança , Pré-Escolar , Estudos de Coortes , Fasciite Necrosante/complicações , Feminino , Hospitalização , Humanos , Lactente , Iowa , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Sistema de Registros , Taxa de Sobrevida , Adulto Jovem
16.
J Burn Care Res ; 30(4): 587-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19506505

RESUMO

Abuse by burning is estimated to occur in 1 to 25% of children admitted with burn injuries annually. Hair and urine toxicology for illicit drug exposure may provide additional confirmatory evidence for abuse. To determine the impact of hair and urine toxicology on the identification of child abuse, we performed a retrospective chart review of all pediatric patients admitted to our burn unit. The medical records of 263 children aged 0 to 16 years of age who were admitted to our burn unit from January 2002 to December 2007 were reviewed. Sixty-five children had suspected abuse. Of those with suspected abuse, 33 were confirmed by the Department of Health and Human Services and comprised the study group. Each of the 33 cases was randomly matched to three pediatric (0-16 years of age) control patients (99). The average annual incidence of abuse in pediatric burn patients was 13.7+/-8.4% of total annual pediatric admissions (range, 0-25.6%). Age younger than 5 years, hot tap water cause, bilateral, and posterior location of injury were significantly associated with nonaccidental burn injury on multivariate analysis. Thirteen (39.4%) abused children had positive ancillary tests. These included four (16%) skeletal surveys positive for fractures and 10 (45%) hair samples positive for drugs of abuse (one patient had a fracture and a positive hair screen). In three (9.1%) patients who were not initially suspected of abuse but later confirmed, positive hair test for illicit drugs was the only indicator of abuse. Nonaccidental injury can be difficult to confirm. Although inconsistent injury history and burn injury pattern remain central to the diagnosis of abuse by burning, hair and urine toxicology offers a further means to facilitate confirmation of abuse.


Assuntos
Queimaduras/epidemiologia , Maus-Tratos Infantis/diagnóstico , Cabelo/química , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Urinálise , Adolescente , Pré-Escolar , Feminino , Fraturas Ósseas/epidemiologia , Humanos , Incidência , Lactente , Modelos Logísticos , Masculino , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/urina
17.
J Burn Care Res ; 29(5): 790-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18695604

RESUMO

Community-associated methicillin-resistant Staphylococcus aureus (MRSA), particularly USA300, is a major pathogen in the outpatient setting. We suspected that USA300 had been introduced into our burn-trauma unit (BTU) when three burn patients presented with numerous simultaneous abscesses. We did molecular typing on 206 MRSA isolates from all patients on the BTU who had MRSA isolated from either nares cultures or clinical specimens obtained between April 11, 2002 and October 24, 2006. We reviewed medical records for all patients who had USA300 and for 75 control patients. Twenty-five of 206 (12.1%) patients who were colonized (n = 3) or infected (n = 22) with MRSA had USA300. Thirteen patients had abscesses drained surgically and eight had necrotizing fasciitis excised. Seven patients had burns (mean burn size 11.8 +/- 3.4%), of who four (66.7%) acquired numerous simultaneous (3-33) abscesses. Fourteen patients acquired USA300 outside of the BTU, and three acquired this strain on the BTU. Cases were more likely to have been hospitalized or to have had an operation in the 6 months before they were hospitalized than were controls (P = .001 for both). To our knowledge, this is the first study to describe numerous simultaneous MRSA abscesses in burn patients. The MRSA strain USA300 may be introduced onto burn units from the community by patients admitted with skin and soft tissue infections, especially abscesses and necrotizing fasciitis. Burn patients may be at risk for numerous abscesses with USA300, because they have open wounds and their immune systems may be compromised.


Assuntos
Queimaduras/complicações , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/epidemiologia , Centros de Traumatologia , Abscesso/etiologia , Abscesso/microbiologia , Antibacterianos/uso terapêutico , Técnicas de Tipagem Bacteriana , Queimaduras/tratamento farmacológico , Queimaduras/epidemiologia , Estudos de Casos e Controles , Fasciite Necrosante/microbiologia , Humanos , Iowa/epidemiologia , Registros Médicos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Estudos Retrospectivos , Índice de Gravidade de Doença , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/efeitos dos fármacos , Estados Unidos/epidemiologia
18.
J Burn Care Res ; 29(4): 574-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18535481

RESUMO

Methamphetamine (MA) is a highly addictive drug that is easily manufactured from everyday household products and chemicals found at local farm stores. The proliferation of small MA labs has led to a dramatic increase in patients sustaining thermal injury while making and/or using MA. We hypothesized that these patients have larger injuries with longer hospital stays, and larger, nonreimbursed hospital bills compared with burn patients not manufacturing or using MA. In a retrospective case-control study, all burn patients >or=16 years of age admitted to our burn center from January 2002 to December 2005 were stratified into two groups based on urine MA status. Of the 660 burn patients >or=16 years of age admitted during this 4 year period, urine drug screens were obtained at admission on 410 patients (62%); 10% of urine drug screens were MA (+). MA (+) patients have larger burns compared with MA (-) patients (9.3 vs 8.6% body surface area burns), have higher rates of inhalation injuries (20.4 vs 9.3%, P = .015), and more nonthermal trauma (13.0 vs 3.1%, P = .001). When compared with MA (-) patients, MA (+) patients require longer hospital stays (median 9.5 vs 7.0 days, P = .036), accrue greater hospital bills per day (dollars 4292 vs dollars 2797, P = .01), and lack medical insurance (66.7 vs 17.7%, P < .0001). The epidemic of MA use and its manufacture mandates that burn centers monitor patients for MA use and develop and institute protocols to ensure proper care of this increasingly costly population.


Assuntos
Queimaduras Químicas/epidemiologia , Estimulantes do Sistema Nervoso Central/efeitos adversos , Crime , Drogas Ilícitas/efeitos adversos , Metanfetamina/efeitos adversos , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Unidades de Queimados , Queimaduras Químicas/patologia , Estudos de Casos e Controles , Estimulantes do Sistema Nervoso Central/urina , Explosões , Custos Hospitalares , Humanos , Drogas Ilícitas/urina , Escala de Gravidade do Ferimento , Seguro Saúde/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Pessoas sem Cobertura de Seguro de Saúde , Metanfetamina/urina , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos/epidemiologia , Estudos Retrospectivos , Violência
19.
J Burn Care Res ; 29(3): 441-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18388580

RESUMO

Burn injuries sustained during residential trash, brush, and grass burning cause significant morbidity and mortality in rural areas. To further prevention efforts, we surveyed individuals who incurred injuries from residential burning. Thirty-six individuals injured while burning trash, brush, or grass from June 2003 through September 2005 were asked to respond to a self-administered written survey. Injury related questions revealed that the majority of those injured were burning brush (21 of 35, 60.0%) in an open space (19 of 35, 54.2%) with the addition of accelerants (27 of 36, 75%). Survey questions regarding usual burning practices revealed almost two-thirds burned either brush or a mixture of brush and trash (23 of 36, 63.9%). Eighty percent of those who were injured desired to change their behavior (25 of 35, 80%). Approximately two-thirds would consider asking for help with burning if it were provided (22 of 34, 64.7%). Our survey shows that acceptable alternatives to burning varied depending on the material that was burned. As the majority of respondents usually burned brush or a mixture of brush and trash, an acceptable trash removal system should also include brush pickup. As residential burning continues presently, injury prevention efforts are essential and should focus on the misuse of gasoline, uniform safety standards for gasoline cans, and dissemination of safe burning practices.


Assuntos
Queimaduras/etiologia , Incêndios , Assunção de Riscos , População Rural , Queimaduras/epidemiologia , Queimaduras/fisiopatologia , Feminino , Humanos , Iowa/epidemiologia , Tempo de Internação , Masculino , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
20.
J Burn Care Res ; 29(1): 138-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18182911

RESUMO

Pseudoephedrine (PSE) is one of the main ingredients used to manufacture methamphetamine (MA); approximately 700 to 1000 PSE pills are necessary to "cook" a batch of MA. Steps have been taken to decrease the availability of ingredients needed to concoct MA. On May 21, 2005, the state of Iowa enacted a strict law, making PSE a Schedule V Controlled substance, restricting PSE availability, and sales. Using the same 6-month time frames in 2004 and 2005, we retrospectively compared epidemiological data on burn patients in the year before the new PSE law and again immediately after the law was enacted. Data collected between May 21 to December 31, 2004 and 2005 included sex, age, length of stay, body surface area burn, urine drug toxicity status, insurance status, and cost of hospital stay. Reports on statewide MA laboratory incidents were provided by the Office of Drug Control Policy. In 2004, Iowa ranked second in the nation for MA lab incidents, seizing an average of 120 labs per month. In 2006, Iowa ranked eighth in the nation for MA lab incidents, when only 20 labs per month were seized, an 83% decreased from the previous year. By limiting the availability of PSE, Iowa saw a marked decrease in MA laboratory-related incidents, leading to a drastic decrease in MA related burns statewide.


Assuntos
Acidentes , Queimaduras/prevenção & controle , Crime/legislação & jurisprudência , Explosões , Drogas Ilícitas/legislação & jurisprudência , Laboratórios/legislação & jurisprudência , Metanfetamina , Pseudoefedrina , Unidades de Queimados , Queimaduras/epidemiologia , Queimaduras/etiologia , Humanos , Iowa/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia
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