Exercise and postprandial thermogenesis in obese women before and after weight loss.

The magnitude of thermogenesis induced by a test meal (17% protein, 54% CHO, and 29% fat) was assessed using indirect calorimetry in six obese women before and after weight loss (mean loss: 11.2 kg) and compared with six nonobese matched controls at rest for 5 h and during and following graded moderate exercise on a bicycle ergometer at three workloads. The test meal contained 60% of the energy expended in basal state over 24 h (736-1020 kcal/meal according to the group). In obese subjects the net absolute increase in energy expenditure (delta EE) in response to the meal was similar between exercising and resting conditions (delta EE = 0.27 vs 0.32 kcal/min, respectively) but tended to be lower in obese women after weight loss (delta EE = 0.19 kcal/min while exercising and 0.25 kcal/min while resting, p less than 0.05) and in control subjects (delta EE = 0.16 vs. 0.25 kcal/min, respectively: p less than 0.05). These results show that the thermogenic response to a meal is not potentiated by moderate exercise.

Relatedness influences signal reliability in evolving robots.

Communication is an indispensable component of animal societies, yet many open questions remain regarding the factors affecting the evolution and reliability of signalling systems. A potentially important factor is the level of genetic relatedness between signallers and receivers. To quantitatively explore the role of relatedness in the evolution of reliable signals, we conducted artificial evolution over 500 generations in a system of foraging robots that can emit and perceive light signals. By devising a quantitative measure of signal reliability, and comparing independently evolving populations differing in within-group relatedness, we show a strong positive correlation between relatedness and reliability. Unrelated robots produced unreliable signals, whereas highly related robots produced signals that reliably indicated the location of the food source and thereby increased performance. Comparisons across populations also revealed that the frequency for signal production-which is often used as a proxy of signal reliability in empirical studies on animal communication-is a poor predictor of signal reliability and, accordingly, is not consistently correlated with group performance. This has important implications for our understanding of signal evolution and the empirical tools that are used to investigate communication.

Reliability and validity of the cross-culturally adapted French version of the Core Outcome Measures Index (COMI) in patients with low back pain.

PURPOSE: To conduct a cross-cultural adaptation of the Core Outcome Measures Index (COMI) into French according to established guidelines. METHODS: Seventy outpatients with chronic low back pain were recruited from six spine centres in Switzerland and France. They completed the newly translated COMI, and the Roland Morris disability (RMQ), Dallas Pain (DPQ), adjectival pain rating scale, WHO Quality of Life, and EuroQoL-5D questionnaires. After ~14 days RMQ and COMI were completed again to assess reproducibility; a transition question (7-point Likert scale; "very much worse" through "no change" to "very much better") indicated any change in status since the first questionnaire. RESULTS: COMI whole scores displayed no floor effects and just 1.5% ceiling effects. The scores for the individual COMI items correlated with their corresponding full-length reference questionnaire with varying strengths of correlation (0.33-0.84, P < 0.05). COMI whole scores showed a very good correlation with the "multidimensional" DPQ global score (Rho = 0.71). 55 patients (79%) returned a second questionnaire with no/minimal change in their back status. The reproducibility of individual COMI 5-point items was good, with test-retest differences within one grade ranging from 89% for 'social/work disability' to 98% for 'symptom-specific well-being'. The intraclass correlation coefficient for the COMI whole score was 0.85 (95% CI 0.76-0.91). CONCLUSIONS: In conclusion, the French version of this short, multidimensional questionnaire showed good psychometric properties, comparable to those reported for German and Spanish versions. The French COMI represents a valuable tool for future multicentre clinical studies and surgical registries (e.g. SSE Spine Tango) in French-speaking countries.

Effect of hypoxia on cerebral blood flow regulation during rest and exercise : role of cerebral oxygen delivery on performance

Adequate supply of oxygen to the brain is critical for maintaining normal brain function. Severe hypoxia, such as that experienced during high altitude ascent, presents a unique challenge to brain oxygen (O2) supply. During high-intensity exercise, hyperventilation-induced hypocapnia leads to cerebral vasoconstriction, followed by reductions in cerebral blood flow (CBF), oxygen delivery (DO2), and tissue oxygenation. This reduced O2 supply to the brain could potentially account for the reduced performance typically observed during exercise in severe hypoxic conditions. The aims of this thesis were to document the effect of acute and chronic exposure to hypoxia on CBF control, and to determine the role of cerebral DO2 and tissue oxygenation in limiting performance during exercise in severe hypoxia. We assessed CBF, arterial O2 content (CaO2), haemoglobin concentration ([Hb]), partial pressure of arterial O2 (PaO2), cerebrovascular CO2 reactivity, ventilatory response to CO2, cerebral autoregulation (CA), and estimated cerebral DO2 (CBF ⨉ CaO2) at sea level (SL), upon ascent to 5,260 m (ALT1), and following 16 days of acclimatisation to 5,260 m (ALT16). We found an increase in CBF despite an elevated cerebrovascular CO2 reactivity at ALT1, which coincided with a reduced CA. Meanwhile, PaO2 was greatly decreased despite increased ventilatory drive at ALT1, resulting in a concomitant decrease in CaO2. At ALT16, CBF decreased towards SL values, while cerebrovascular CO2 reactivity and ventilatory drive were further elevated. Acclimatisation increased PaO2, [Hb], and therefore CaO2 at ALT16, but these changes did not improve CA compared to ALT1. No differences were observed in cerebral DO2 across SL, ALT1, and ALT16. Our findings demonstrate that cerebral DO2 is maintained during both acute and chronic exposure to 5,260 m, due to the reciprocal changes in CBF and CaO2. We measured middle cerebral artery velocity (MCAv: index of CBF), cerebral DO2, ventilation (VE), and performance during incremental cycling to exhaustion and 15km time trial cycling in both normoxia and severe hypoxia (11% O2, normobaric), with and without added CO2 to the inspirate (CO2 breathing). We found MCAv was higher during exercise in severe hypoxia compared in normoxia, while cerebral tissue oxygenation and DO2 were reduced. CO2 breathing was effective in preventing the development of hyperventilation-induced hypocapnia during intense exercise in both normoxia and hypoxia. As a result, we were able to increase both MCAv and cerebral DO2 during exercise in hypoxia with our CO2 breathing setup. However, we concomitantly increased VE and PaO2 (and presumably respiratory work) due to the increased hypercapnic stimuli with CO2 breathing, which subsequently contributed to the cerebral DO2 increase during hypoxic exercise. While we effectively restored cerebral DO2 during exercise in hypoxia to normoxic values with CO2 breathing, we did not observe any improvement in cerebral tissue oxygenation or exercise performance. Accordingly, our findings do not support the role of reduced cerebral DO2 in limiting exercise performance in severe hypoxia. -- Un apport adéquat en oxygène au niveau du cerveau est primordial pour le maintien des fonctions cérébrales normales. L'hypoxie sévère, telle qu'expérimentée au cours d'ascensions en haute altitude, présente un défi unique pour l'apport cérébral en oxygène (O2). Lors d'exercices à haute intensité, l'hypocapnie induite par l'hyperventilation entraîne une vasoconstriction cérébrale suivie par une réduction du flux sanguin cérébral (CBF), de l'apport en oxygène (DO2), ainsi que de l'oxygénation tissulaire. Cette réduction de l'apport en O2 au cerveau pourrait potentiellement être responsable de la diminution de performance observée au cours d'exercices en condition d'hypoxie sévère. Les buts de cette thèse étaient de documenter l'effet de l'exposition aiguë et chronique à l'hypoxie sur le contrôle du CBF, ainsi que de déterminer le rôle du DO2 cérébral et de l'oxygénation tissulaire comme facteurs limitant la performance lors d'exercices en hypoxie sévère. Nous avons mesuré CBF, le contenu artériel en oxygène (CaO2), la concentration en hémoglobine ([Hb]), la pression partielle artérielle en O2 (PaO2), la réactivité cérébrovasculaire au CO2, la réponse ventilatoire au CO2, et l'autorégulation cérébrale sanguine (CA), et estimé DO2 cérébral (CBF x CaO2), au niveau de la mer (SL), au premier jour à 5.260 m (ALT1) et après seize jours d'acclimatation à 5.260 m (ALT16). Nous avons trouvé des augmentations du CBF et de la réactivité cérébrovasculaire au CO2 après une ascension à 5.260 m. Ces augmentations coïncidaient avec une réduction de l'autorégulation cérébrale. Simultanément, la PaO2 était grandement réduite, malgré l'augmentation de la ventilation (VE), résultant en une diminution de la CaO2. Après seize jours d'acclimatation à 5.260 m, le CBF revenait autour des valeurs observées au niveau de la mer, alors que la réactivité cérébrovasculaire au CO2 et la VE augmentaient par rapport à ALT1. L'acclimatation augmentait la PaO2, la concentration en hémoglobine, et donc la CaO2, mais n'améliorait pas l'autorégulation cérébrale, comparé à ALT1. Aucune différence n'était observée au niveau du DO2 cérébral entre SL, ALT1 et ALT16. Nos résultats montrent que le DO2 cérébral est maintenu constant lors d'expositions aiguë et chronique à 5.260m, ce qui s'explique par la réciprocité des variations du CBF et de la CaO2. Nous avons mesuré la vitesse d'écoulement du sang dans l'artère cérébrale moyenne (MCAv : un indice du CBF), le DO2 cérébral, la VE et la performance lors d'exercice incrémentaux jusqu'à épuisement sur cycloergomètre, ainsi que des contre-la-montres de 15 km en normoxie et en hypoxie sévère (11% O2, normobarique) ; avec ajout ou non de CO2 dans le mélange gazeux inspiré. Nous avons trouvé que MCAv était plus haute pendant l'exercice hypoxique, comparé à la normoxie alors que le DO2 cérébral était réduit. L'ajout de CO2 dans le gaz inspiré était efficace pour prévenir l'hypocapnie induite par l'hyperventilation, qui se développe à l'exercice intense, à la fois en normoxie et en hypoxie. Nous avons pu augmenter MCAv et le DO2 cérébral pendant l'exercice hypoxique, grâce à l'ajout de CO2. Cependant, nous avons augmenté la VE et la PaO2 (et probablement le travail respiratoire) à cause de l'augmentation du stimulus hypercapnique. Alors que nous avons, grâce à l'ajout de CO2, efficacement restauré le DO2 cérébral au cours de l'exercice en hypoxie à des valeurs obtenues en normoxie, nous n'avons observé aucune amélioration dans l'oxygénation du tissu cérébral ou de la performance. En conséquence, nos résultats ne soutiennent pas le rôle d'un DO2 cérébral réduit comme facteur limitant de la performance en hypoxie sévère.

Impaired musculoskeletal response to age and exercise in PPARβ(-/-) diabetic mice.

Fragility fractures are recognized complication of diabetes, but yet the underlying mechanisms remain poorly understood. This is particularly pronounced in type 2 diabetes in which the propensity to fall is increased but bone mass is not necessarily low. Thus, whether factors implicated in the development of insulin resistance and diabetes directly impact on the musculoskeletal system remains to be investigated. PPARβ(-/-) mice have reduced metabolic activity and are glucose intolerant. We examined changes in bone and muscle in PPARβ(-/-) mice and investigated both the mechanism behind those changes with age as well as their response to exercise. Compared with their wild type, PPARβ(-/-) mice had an accelerated and parallel decline in both muscle and bone strength with age. These changes were accompanied by increased myostatin expression, low bone formation, and increased resorption. In addition, mesenchymal cells from PPARβ(-/-) had a reduced proliferation capacity and appeared to differentiate into more of an adipogenic phenotype. Concomitantly we observed an increased expression of PPARγ, characteristic of adipocytes. The anabolic responses of muscle and bone to exercise were also diminished in PPARβ(-/-) mice. The periosteal bone formation response to direct bone compression was, however, maintained, indicating that PPARβ controls periosteal bone formation through muscle contraction and/or metabolism. Taken together, these data indicate that PPARβ deficiency leads to glucose intolerance, decreased muscle function, and reduced bone strength. On a molecular level, PPARβ appears to regulate myostatin and PPARγ expression in muscle and bone, thereby providing potential new targets to reverse bone fragility in patients with metabolic disturbances.

A neuropsychological instrument measuring age-related cerebral decline in older drivers: development, reliability, and validity of MedDrive.

When facing age-related cerebral decline, older adults are unequally affected by cognitive impairment without us knowing why. To explore underlying mechanisms and find possible solutions to maintain life-space mobility, there is a need for a standardized behavioral test that relates to behaviors in natural environments. The aim of the project described in this paper was therefore to provide a free, reliable, transparent, computer-based instrument capable of detecting age-related changes on visual processing and cortical functions for the purposes of research into human behavior in computational transportation science. After obtaining content validity, exploring psychometric properties of the developed tasks, we derived (Study 1) the scoring method for measuring cerebral decline on 106 older drivers aged ≥70 years attending a driving refresher course organized by the Swiss Automobile Association to test the instrument's validity against on-road driving performance (106 older drivers). We then validated the derived method on a new sample of 182 drivers (Study 2). We then measured the instrument's reliability having 17 healthy, young volunteers repeat all tests included in the instrument five times (Study 3) and explored the instrument's psychophysical underlying functions on 47 older drivers (Study 4). Finally, we tested the instrument's responsiveness to alcohol and effects on performance on a driving simulator in a randomized, double-blinded, placebo, crossover, dose-response, validation trial including 20 healthy, young volunteers (Study 5). The developed instrument revealed good psychometric properties related to processing speed. It was reliable (ICC = 0.853) and showed reasonable association to driving performance (R (2) = 0.053), and responded to blood alcohol concentrations of 0.5 g/L (p = 0.008). Our results suggest that MedDrive is capable of detecting age-related changes that affect processing speed. These changes nevertheless do not necessarily affect driving behavior.

Intraclass reliability of the Alberta Infant Motor Scale in the Brazilian version

This study had as its objective to analyze the intraclass reliability of the Alberta Infant Motor Scale (AIMS), in the Brazilian version, in preterm and term infants. It was a methodological study, conducted from November 2009 to April 2010, with 50 children receiving care in two public institutions in Fortaleza, Ceará, Brazil. Children were grouped according to gestational age as preterm and term, and evaluated by three evaluators in the communication laboratory of a public institution or at home. The intraclass correlation indices for the categories prone, supine, sitting and standing ranged from 0.553 to 0.952; most remained above 0.800, except for the standing category of the third evaluator, in which the index was 0.553. As for the total score and percentile, rates ranged from 0.843 to 0.954. The scale proved to be a reliable instrument for assessing gross motor performance of Brazilian children, particularly in Ceará, regardless of gestational age at birth.

Validity and reliability of a questionnaire on knowledge of cardiovascular risk factors for use in Brazil

Using a sample of patients with coronary artery disease, this methodological study aimed to conduct a cross-cultural adaptation and validation of a questionnaire on knowledge of cardiovascular risk factors (Q-FARCS), lifestyle changes, and treatment adherence for use in Brazil. The questionnaire has three scales: general knowledge of risk factors (RFs); specific knowledge of these RFs; and lifestyle changes achieved. Cross-cultural adaptation included translation, synthesis, back-translation, expert committee review, and pretesting. Face and content validity, reliability, and construct validity were measured. Cronbach’s alpha for the total sample (n = 240) was 0.75. Assessment of psychometric properties revealed adequate face and content validity, and the construct revealed seven components. It was concluded that the Brazilian version of Q-FARCS had adequate reliability and validity for the assessment of knowledge of cardiovascular RFs.

Impact of the disease: acceptability, ceiling and floor effects and reliability of an instrument on heart failure

This study evaluated the acceptability, ceiling/floor effects, and the reliability of the instrument for measuring the Impact of the Disease on the Daily Life of Patients with Valvular Disease (IDCV) when applied to 135 patients with heart failure (HF). Acceptability was evaluated by the percentage of unanswered items and by the proportion of patients who responded to all items; the ceiling/floor effects by the percentage of patients who scored in the top of 10% best and worst results of the scale, respectively. Reliability was estimated by internal consistency (Cronbach's alpha coefficient) and stability of the measure (intraclass correlation coefficient - ICC). All patients responded to all items. Ceiling/floor effects evidenced were of moderate magnitude. The Cronbach's alpha was satisfactory for the majority of the domains and ICC> 0.90 in all the domains. The IDCV proved to be an easy to understand questionnaire, with evidence of reliability in patients with HF.

Fat oxidation kinetics during exercise in obese individuals

Introduction An impaired ability to oxidize fat may be a factor in the obesity's aetiology (3). Moreover, the exercise intensity (Fatmax) eliciting the maximal fat oxidation rate (MFO) was lower in obese (O) compared with lean (L) individuals (4). However, difference in fat oxidation rate (FOR) during exercise between O and L remains equivocal and little is known about FORs during high intensities (>60% ) in O compared with L. This study aimed to characterize fat oxidation kinetics over a large range of intensities in L and O. Methods 12 healthy L [body mass index (BMI): 22.8±0.4] and 16 healthy O men (BMI: 38.9±1.4) performed submaximal incremental test (Incr) to determine whole-body fat oxidation kinetics using indirect calorimetry. After a 15-min resting period (Rest) and 10-min warm-up at 20% of maximal power output (MPO, determined by a maximal incremental test), the power output was increased by 7.5% MPO every 6-min until respiratory exchange ratio reached 1.0. Venous lactate and glucose and plasma concentration of epinephrine (E), norepinephrine (NE), insulin and non-esterified fatty acid (NEFA) were assessed at each step. A mathematical model (SIN) (1), including three variables (dilatation, symmetry, translation), was used to characterize fat oxidation (normalized by fat-free mass) kinetics and to determine Fatmax and MFO. Results FOR at Rest and MFO were not significantly different between groups (p≥0.1). FORs were similar from 20-60% (p≥0.1) and significantly lower from 65-85% in O than in L (p≤0.04). Fatmax was significantly lower in O than in L (46.5±2.5 vs 56.7±1.9 % respectively; p=0.005). Fat oxidation kinetics was characterized by similar translation (p=0.2), significantly lower dilatation (p=0.001) and tended to a left-shift symmetry in O compared with L (p=0.09). Plasma E, insulin and NEFA were significantly higher in L compared to O (p≤0.04). There were no significant differences in glucose, lactate and plasma NE between groups (p≥0.2). Conclusion The study showed that O presented a lower Fatmax and a lower reliance on fat oxidation at high, but not at moderate, intensities. This may be linked to a: i) higher levels of insulin and lower E concentrations in O, which may induce blunted lipolysis; ii) higher percentage of type II and a lower percentage of type I fibres (5), and iii) decreased mitochondrial content (2), which may reduce FORs at high intensities and Fatmax. These findings may have implications for an appropriate exercise intensity prescription for optimize fat oxidation in O. References 1. Cheneviere et al. Med Sci Sports Exerc. 2009 2. Holloway et al. Am J Clin Nutr. 2009 3. Kelley et al. Am J Physiol. 1999 4. Perez-Martin et al. Diabetes Metab. 2001 5. Tanner et al. Am J Physiol Endocrinol Metab. 2002

Scientific Literature on the Reliability and Validity of the Manchester Triage System (MTS) Protocol: A Integrative Literature Review

OBJECTIVE To analyze the scientific production about the validity and reliability of the Manchester Triage System (MTS) protocol. METHOD A descriptive study of an integrative literature review. Articles on the validity and reliability of the MTS developed with children and adults published between 1999 and 2013 were included. RESULTS 14 articles were selected from a total of 8438, nine of validity and five of reliability. The reliability of the MTS ranged from moderate to almost perfect, with higher intra-evaluation. Regarding validity, the results seem to point to equivalent and satisfactory sensibility and specificity levels of the MTS. The instrument proved to be a good predictor of the need for hospitalization and of hospital mortality. CONCLUSION The reliability and validity of the MTS obtained in the studies is varied. It is recommended that new studies indicate necessary modifications to the MTS so that it is more safely used by nurses.

A Atitude do Contabilista perante Dilemas Éticos

Casos de fraudes têm ocorrido, frequentemente no mercado mundial. Diversos são os profissionais envolvidos nesses casos, inclusive os da contabilidade. Os escândalos contabilísticos, especialmente os mais famosos, como os incidido nas empresas Enron e Wordcom, acenderam para uma maior preocupação em relação a conduta ética dos profissionais da contabilidade. Como consequência há uma maior exigência quanto a transparência e a fidedignidade das informações prestadas por estes profissionais. Esta preocupação visa, sobretudo, manter a confiança das empresas, investidores, fornece-dores e sociedade em geral, de entre outras, na responsabilidade ética do contabilista, de-negrida pelo envolvimento nas fraudes detectadas. Desta forma, o presente estudo teve como objectivo verificar a conduta ética dos contabilistas, quando, no exercício da sua profissão, depararem com questões relacionadas a fraudes. Nesse sentido considerou-se factores que podem vir a influenciar o processo decisório ético de um indivíduo, demonstrados através do modelo de tomada de decisão, desenvolvido por Alves, quanto a motivar um indivíduo a cometer uma fraude, evidenciada através do modelo desenvolvido por Cressey. Tentando responder a questão norteadora desta pesquisa, executou-se a análise descritiva e estatística dos dados. Em relação a análise descritiva, foram elaboradas tabelas de frequência. Para a análise estatística dos dados foi utilizado o teste não paramétrico de Spearman. Os resultados demonstraram que a maioria dos contabilistas, da amostra pesquisada, reconhece a questão moral inserida nos cenários, e discordam dos actos dos agentes de cada cenário, e, ainda os classificam como graves ou muito graves. A pesquisa revelou maior aproximação desses profissionais a corrente teleológica, uma vez que a intenção de agir é mais influenciada por alguns factores como a oportunidade, a racionalização e principalmente a pressão. Alguns factores individuais apresentam influências sob o posicionamento ético dos contabilistas entrevistados nesta pesquisa. Cases of fraud have occurred, in the word market. Several are involved in these cases, including the accounting class. The accounting scandals, especially the most famous, such as focusing on companies and Enron Word Com, kindled to greater concern about the ethical conduct of professional accounting. As a result there is a greater demand on the transparency and reliability of information provide by these professionals This concern is aimed, primarily, to maintain the confidence of businesses, investor, suppliers and society, among others, the ethical responsibility of the meter, denigrated, by involvement in the fraud detected. Thus, this study aimed to verify the ethical conduct of accounts in when, in the exercise of their professional activities, is confronted with issues related to fraud. This is considered some factors that can both come to influence the ethical decision making of an individual, demonstrated by the model of decision making, developed by Alves, as a motivated individual to commit a fraudulent act, developed by Cressey. Seeking to answer question, guiding this study, performed to exploratory and confirmatory analysis of data. For exploratory data analysis were made table of frequencies. For confirmatory analysis of data, were used non parametric tests of Spearman. The results showed that the majority of accountings professionals, the sample, recognizing the moral issue included in the scenarios, disagrees the acts of agents of each scenario, and also classifies such acts as serious and very serious. However, we found that these accounting professionals tend to have a position more toward the teleological theory, since the intention to act is influenced by factors as opportunity, rationalization and particularly the pressure. Some individual factors also had influence on the ethical position of the professional interviewed is this research.