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1.
Nutr Rev ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37944081

RESUMO

CONTEXT: Obesity has emerged as a global health issue for the pediatric population, increasing the need to investigate physiopathological aspects to prevent the appearance of its cardiometabolic complications. Chrononutrition is a field of research in nutritional sciences that investigates the health impact of 3 different dimensions of feeding behavior: regularity of meals, frequency, and timing of food intake. OBJECTIVE: We carried out a systematic review and meta-analysis to investigate the association between chrononutrition in children and adolescents and the risk of overweight/obesity or a cluster of metabolic abnormalities related to glucose and lipid metabolism, blood pressure, and cardiovascular disease risk. DATA EXTRACTION: A literature search was performed using PubMed, EMBASE, and The Cochrane Library for relevant articles published before August 2022. DATA ANALYSIS: A total of 64 articles were included in the narrative synthesis (47 cross-sectional and 17 cohort studies), while 16 studies were included in the meta-analysis. Meta-analysis showed that non-daily breakfast consumers (≤6 d/wk) had a higher risk of overweight/obesity (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.08-1.82] compared with daily breakfast eaters (7 d/wk). Similarly, irregular breakfast consumption (only 0-to-3 times/wk) increased the risk of abdominal obesity (waist-to-height ratio ≥ 0.5) compared with regular consumption (5-to-7 times/wk) (OR, 1.38; 95% CI, 1.26-1.49). There was evidence to suggest that a regular frequency of meal consumption (≥4 times/d) is preventive against overweight/obesity development compared with fewer meals (≤3 times/d) (OR, 0.83; 95% CI, 0.70-0.97). In the narrative synthesis, snacking habits showed controversial results, while food timing was the most understudied dimension. CONCLUSION: Overall, our data indicate a potential implication of chrononutrition in affecting pediatric metabolic health; however, the evidence of this association is limited and heterogeneous. Further prospective and intervention studies with a consistent approach to categorize the exposure are needed to elucidate the importance of chrononutrition for pediatric metabolic health.

3.
Clin Exp Allergy ; 44(4): 499-507, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24341600

RESUMO

BACKGROUND: The role of small airway obstruction in the clinical expression of asthma is incompletely understood. OBJECTIVE: We tested the hypotheses that markers of small airway obstruction are associated with (i) increased asthma severity, (ii) impaired asthma control and quality of life and (iii) frequent exacerbations. METHODS: Seventy-four adults with asthma and 18 healthy control subjects underwent impulse oscillometry (IOS), multiple breath inert gas washout (MBW), body plethysmography, single-breath determination of carbon monoxide uptake and spirometry. Patients completed the six-point Asthma Control Questionnaire (ACQ-6) and standardized Asthma Quality of Life Questionnaire [AQLQ(S)]. Asthma severity was classified according to the Global Initiative for Asthma (GINA) treatment steps. RESULTS: The putative small airway obstruction markers Sacin , resistance at 5 Hz minus resistance at 20 Hz (R5-R20) and reactance area (AX) were not independently associated with asthma severity, control, quality of life or exacerbations. In contrast, markers of total (R5) and mean airway resistance of large and small airways (R20) were significantly higher in the severe asthma group compared with the mild-moderate group (0.47 vs. 0.37, P < 0.05 for R5; 0.39 vs. 0.31, P < 0.01 for R20). The strongest independent contributors to ACQ-6 score were R20 and forced expiratory volume in one second (% pred.), and the strongest independent contributors to AQLQ(S) score were R20 and forced vital capacity (% pred.). A history of one or more exacerbations within the previous year was independently associated with R20. CONCLUSIONS AND CLINICAL RELEVANCE: Previously reported markers of small airway obstruction do not appear to be independently associated with asthma disease expression. In contrast, the IOS parameter R20, a marker of mean airway resistance of both large and small airways, appears to have independent clinical significance. These observations require confirmation in prospective longitudinal studies.


Assuntos
Obstrução das Vias Respiratórias/fisiopatologia , Asma/diagnóstico , Asma/fisiopatologia , Asma/tratamento farmacológico , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados da Assistência ao Paciente , Testes de Função Respiratória , Fatores de Risco , Índice de Gravidade de Doença
4.
Proc Natl Acad Sci U S A ; 105(28): 9495-500, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18621701

RESUMO

Global efforts to conserve biodiversity have the potential to deliver economic benefits to people (i.e., "ecosystem services"). However, regions for which conservation benefits both biodiversity and ecosystem services cannot be identified unless ecosystem services can be quantified and valued and their areas of production mapped. Here we review the theory, data, and analyses needed to produce such maps and find that data availability allows us to quantify imperfect global proxies for only four ecosystem services. Using this incomplete set as an illustration, we compare ecosystem service maps with the global distributions of conventional targets for biodiversity conservation. Our preliminary results show that regions selected to maximize biodiversity provide no more ecosystem services than regions chosen randomly. Furthermore, spatial concordance among different services, and between ecosystem services and established conservation priorities, varies widely. Despite this lack of general concordance, "win-win" areas-regions important for both ecosystem services and biodiversity-can be usefully identified, both among ecoregions and at finer scales within them. An ambitious interdisciplinary research effort is needed to move beyond these preliminary and illustrative analyses to fully assess synergies and trade-offs in conserving biodiversity and ecosystem services.


Assuntos
Carbono , Conservação dos Recursos Naturais , Ecossistema , Mapas como Assunto , Biodiversidade , Geografia
5.
Psychopharmacology (Berl) ; 158(2): 146-53, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702088

RESUMO

RATIONALE: The relative contributions of different dopamine receptor subtypes to the discriminative stimulus effects of cocaine may be influenced by the training dose of cocaine. Substitution tests with dopamine receptor agonists have suggested that the role of dopamine D2-like receptors is diminished relative to that of D1-like receptors at a training dose of 3 mg/kg cocaine compared with a training dose of 10 mg/kg. OBJECTIVES: To test whether dopamine D2-like receptor antagonists were differentially effective at attenuating cocaine's discriminative stimulus effects at different training doses, and to test for the first time an antagonist that is selective for the dopamine D2 receptor within the D2-like receptor subfamily. METHODS: Rats were trained to press one lever after receiving cocaine and another after receiving saline (maintaining >95% drug-appropriate responding). Three dopamine D2-like receptor antagonists (haloperidol, raclopride and L-741,626) were tested in rats trained at 3 mg/kg or 10 mg/kg cocaine. At the lower training dose, the D1-like receptor antagonist SCH 39166 was also tested. RESULTS: The antagonists were not differentially effective between training groups: they all produced parallel, rightward shifts in cocaine's dose-effect function, indicating surmountable antagonism. CONCLUSIONS: The results demonstrate that D2-like receptor antagonists with different affinities for the various D2-like receptors can antagonise the discriminative stimulus effects of cocaine at two training doses. Importantly, antagonism by L-741,626 implies that stimulation of D2 receptors alone (not D3 or D4 receptors) is sufficient to mediate cocaine's discriminative stimulus effects. Finally, the claim that D1-like receptors are preferentially involved at low training doses of cocaine is only consistent with the current findings if indirect stimulation of D2 receptors by low doses of cocaine remains necessary for the expression of the D1-like receptor-mediated effect.


Assuntos
Cocaína/administração & dosagem , Discriminação Psicológica/efeitos dos fármacos , Antagonistas de Dopamina/farmacologia , Antagonistas dos Receptores de Dopamina D2 , Inibidores da Captação de Dopamina/administração & dosagem , Animais , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Discriminação Psicológica/fisiologia , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Masculino , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Receptores de Dopamina D2/fisiologia
7.
Trends Ecol Evol ; 14(2): 69-70, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10234284
8.
Science ; 281(5374): 198-9, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9660740

RESUMO

Pressures being exerted on the ocean ecosystems through overfishing, pollution, and environmental and climate change are increasing. Six core principles are proposed to guide governance and use of ocean resources and to promote sustainability. Examples of governance structures that embody these principles are given.

9.
Eur J Pharmacol ; 345(2): 129-32, 1998 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-9600627

RESUMO

The contribution of dopamine D4 receptors to the discriminative stimulus effects of cocaine was evaluated by testing the selective dopamine D4 receptor antagonist, L-745,870 (3-([4-(4-chlororphenyl) piperazin-1-yl] methyl)-1 H-pyrrolo[2,3-b] pyridine), alone and in combination with cocaine, in rats trained to discriminate cocaine (10 mg/kg) from saline. The antagonist (1-10 mg/kg) failed to engender cocaine-appropriate responding when injected alone, and failed to modify the cocaine dose-response curve when injected as a pre-treatment; however, it reduced response rates dose-dependently. Conversely, the dopamine 'D1-like' receptor antagonist, SCH 39166 ((-)-trans-6,7,7a,8,9, 13b-hexahydro-3-chloro-2hydroxy-N-methyl-5H-benzo[d]napth o-¿2,1-b¿azepine, produced surmountable antagonism. Results suggest that dopamine D4 receptors play a negligible role in cocaine's discriminative stimulus effects, and further support a critical involvement of dopamine D1-like receptors.


Assuntos
Cocaína/administração & dosagem , Discriminação Psicológica/efeitos dos fármacos , Antagonistas de Dopamina/farmacologia , Piridinas/farmacologia , Pirróis/farmacologia , Receptores de Dopamina D2/efeitos dos fármacos , Animais , Condicionamento Operante/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/fisiologia , Receptores de Dopamina D4
10.
Environ Manage ; 22(2): 183-95, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9465128

RESUMO

/ This paper assesses the changing role of dynamic modeling for understanding and managing complex ecological economic systems. It discusses new modeling tools for problem scoping and consensus building among a broad range of stakeholders and describes four case studies in which dynamic modeling has been used to collect and organize data, synthesize knowledge, and build consensus about the management of complex systems. The case studies range from industrial systems (mining, smelting, and refining of iron and steel in the United States) to ecosystems (Louisiana coastal wetlands, and Fynbos ecosystems in South Africa) to linked ecological economic systems (Maryland's Patuxent River basin in the United States). They illustrate uses of dynamic modeling to include stakeholders in all stages of consensus building, ranging from initial problem scoping to model development. The resultant models are the first stage in a three-stage modeling process that includes research and management models as the later stages.KEY WORDS: Dynamic modeling; Scoping; Consensus building; Environmental management; Ecosystem management; Policy making; Graphical programming languages

11.
Trends Ecol Evol ; 13(10): 397-402, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21238359

RESUMO

Evaluating ecosystem health in relation to the ecological, economic and human health spheres requires integrating human values with biophysical processes, an integration that has been explicitly avoided by conventional science. The field is advancing with the articulation of the linkages between human activity, regional and global environmental change, reduction in ecological services and the consequences for human health, economic opportunity and human communities. Increasing our understanding of these interactions will involve more active collaboration between the ecological, social and health sciences. In this, ecologists will have substantive and catalytic roles.

13.
NPG Forum Ser ; : 1-6, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12178976

RESUMO

PIP: Cultural evolution has allowed humans to change their behaviors and adapt to new conditions much faster than biological evolution. The most critical of these is the overpopulation trap, caused by the imbalance between the short-term incentives to have children and the longterm social and ecological costs of having too many. This process of short-run incentives getting out of sync with longterm goals has been called social traps, as the decision maker is trapped by the local conditions into making a bad decision viewed from a longer perspective. The biological and cultural incentives to procreate combined with rapid reductions in mortality have changed the long-run ecological cost structure. The elimination of social traps requires intervention by education (about the longterm, distributed impacts), insurance, superordinate authority (legal systems, government, religion), and converting the trap to a trade-off. In a sense, this is an extension of the polluter pays principle. Summary suggestions: establish a hierarchy of goals for national and global ecological economic planning and management, sustainability should be the primary longterm goal, replacing the current GNP growth mania; develop better global ecological economic models about the interrelated impacts of population, per capita resource use, and wealth distribution; adjust current incentives to reflect long-run, global costs, including uncertainty; and allow no further decline in the stock of natural capital by taxing natural capital consumption. The US population in 1986 was about 240 million. Current technology and consumption patterns from renewable energy alone could sustain about 85 million people, or about 35% of the current population, or with a more equitable distribution 170 million at a high quality life style on renewable energy alone.^ieng


Assuntos
Conservação dos Recursos Naturais , Cultura , Economia , Governo , Recursos em Saúde , Formulação de Políticas , Densidade Demográfica , Dinâmica Populacional , Comportamento Sexual , Ajustamento Social , Impostos , América , Comportamento , Demografia , Países Desenvolvidos , Meio Ambiente , Fertilidade , Administração Financeira , Planejamento em Saúde , América do Norte , Organização e Administração , Política , População , Comportamento Social , Estados Unidos
14.
Science ; 230(4727): 740, 1985 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17791779
15.
Science ; 225(4665): 890-7, 1984 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-17779848

RESUMO

A series of hypotheses is presented about the relation of national energy use to national economic activity (both time series and cross-sectional) which offer a different perspective from standard economics for the assessment of historical and current economic events. The analysis incorporates nearly 100 years of time series data and 3 years of cross-sectional data on 87 sectors of the United States economy. Gross national product, labor productivity, and price levels are all correlated closely with various aspects of energy use, and these correlations are improved when corrections are made for energy quality. A large portion of the apparent increase in U.S. energy efficiency has been due to our ability to expand the relative use of high-quality fuels such as petroleum and electricity, and also to relative shifts in fuel use between sectors of the economy. The concept of energy return on investment is introduced as a major driving force in our economy, and data are provided which show a marked decline in energy return on investment for all our principal fuels in recent decades. Future economic growth will depend largely on the net energy yield of alternative fuel sources, and some standard economic models may need to be modified to account for the biophysical constraints on human economic activity.

16.
Science ; 216(4550): 1143, 1982 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-17808505
17.
Science ; 210(4475): 1219-24, 1980 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-17810761

RESUMO

Input-output analysis has been adapted to calculate the total (direct plus indirect) energy required to produce goods and services in the U.S. economy; this quantity has been termed the embodied energy. Usually, the energy required to produce labor and government services and the solar energy input to the economy are ignored by analysts. The former omission can be traced to the assumption that traditional primary factors of economic production-land, labor, and capital-are independent. A strong case can be made that these input factors are not independent and that energy is required for their production. Embodied energies can be calculated in this case by using input-output data. The results of such an analysis show that there is a strong relation between embodied energy and dollar value for a 92-sector U.S. economy if the energy required to produce labor and government services is included.

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