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1.
Curr Allergy Asthma Rep ; 22(12): 209-229, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36374376

RESUMEN

PURPOSE OF REVIEW: Non-steroidal exacerbated respiratory disease (N-ERD) currently requires aspirin challenge testing for diagnosis. Urinary leukotriene E4 (uLTE4) has been extensively investigated as potential biomarker in N-ERD. We aimed to assess the usefulness of uLTE4 as a biomarker in the diagnosis of N-ERD. RECENT FINDINGS: N-ERD, formerly known as aspirin-intolerant asthma (AIA), is characterised by increased leukotriene production. uLTE4 indicates cysteinyl leukotriene production, and a potential biomarker in N-ERD. Although several studies and have examined the relationship between uLTE4 and N-ERD, the usefulness of uLTE4 as a biomarker in a clinical setting remains unclear. FINDINGS: Our literature search identified 38 unique eligible studies, 35 were included in the meta-analysis. Meta-analysis was performed (i.e. pooled standardised mean difference (SMD) with 95% confidence intervals (95% CI)) and risk of bias assessed (implementing Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy (Cochrane DTA)). Data from 3376 subjects was analysed (1354 N-ERD, 1420 ATA, and 602 HC). uLTE4 was higher in N-ERD vs ATA (n = 35, SMD 0.80; 95% CI 0.72-0.89). uLTE4 increased following aspirin challenge in N-ERD (n = 12, SMD 0.56; 95% CI 0.26-0.85) but not ATA (n = 8, SMD 0.12; CI - 0.08-0.33). This systematic review and meta-analysis showed that uLTE4 is higher in N-ERD than ATA or HC. Likewise, people with N-ERD have greater increases in uLTE4 following aspirin challenge. However, due to the varied uLTE4 measurement and result reporting practice, clinical utility of these findings is limited. Future studies should be standardised to increase clinical significance and interpretability of the results.


Asunto(s)
Antiinflamatorios no Esteroideos , Leucotrieno E4 , Humanos , Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos
2.
Ecol Appl ; 31(7): e02417, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34278647

RESUMEN

Many secondary deciduous forests of eastern North America are approaching a transition in which mature early-successional trees are declining, resulting in an uncertain future for this century-long carbon (C) sink. We initiated the Forest Accelerated Succession Experiment (FASET) at the University of Michigan Biological Station to examine the patterns and mechanisms underlying forest C cycling following the stem girdling-induced mortality of >6,700 early-successional Populus spp. (aspen) and Betula papyrifera (paper birch). Meteorological flux tower-based C cycling observations from the 33-ha treatment forest have been paired with those from a nearby unmanipulated forest since 2008. Following over a decade of observations, we revisit our core hypothesis: that net ecosystem production (NEP) would increase following the transition to mid-late-successional species dominance due to increased canopy structural complexity. Supporting our hypothesis, NEP was stable, briefly declined, and then increased relative to the control in the decade following disturbance; however, increasing NEP was not associated with rising structural complexity but rather with a rapid 1-yr recovery of total leaf area index as mid-late-successional Acer, Quercus, and Pinus assumed canopy dominance. The transition to mid-late-successional species dominance improved carbon-use efficiency (CUE = NEP/gross primary production) as ecosystem respiration declined. Similar soil respiration rates in control and treatment forests, along with species differences in leaf physiology and the rising relative growth rates of mid-late-successional species in the treatment forest, suggest changes in aboveground plant respiration and growth were primarily responsible for increases in NEP. We conclude that deciduous forests transitioning from early to middle succession are capable of sustained or increased NEP, even when experiencing extensive tree mortality. This adds to mounting evidence that aging deciduous forests in the region will function as C sinks for decades to come.


Asunto(s)
Ecosistema , Pinus , Carbono , Bosques , Árboles
3.
J Pharmacol Exp Ther ; 374(2): 273-282, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32385092

RESUMEN

Methylenedioxypyrovalerone (MDPV) is an abused synthetic cathinone, commonly referred to as a "bath salt." Because the dopamine (DA) transporter (DAT) and vesicular monoamine transporter-2 (VMAT-2) are key regulators of both the abuse and neurotoxic potential of structurally and behaviorally related agents, the impact of MDPV on these transporters was investigated. Results revealed that a single in vivo MDPV administration rapidly (within 1 hour) and reversibly increased both rat striatal DAT and VMAT-2 activity, as assessed via [3H]DA uptake in synaptosomes and synaptic vesicles, respectively, prepared from treated rats. There was no evidence of an MDPV-induced increase in plasmalemmal membrane DAT surface expression. Plasma concentrations of MDPV increased dose-dependently as assessed 1 hour after 2.5 and 5.0 mg/kg (s.c.) administration and returned to levels less than 10 ng/ml by 18 hours after 2.5 mg/kg (s.c.). Neither pretreatment with a D1 receptor (SCH23390), a D2 receptor (eticlopride), nor a nicotinic receptor (mecamylamine) antagonist attenuated the MDPV-induced increase in DAT activity. In contrast, eticlopride pretreatment attenuated both the MDPV-induced increase in VMAT-2-mediated DA uptake and an associated increase in cytoplasmic-associated vesicle VMAT-2 immunoreactivity. SCH23390 did not attenuate the MDPV-induced increase in VMAT-2 activity. Repeated MDPV injections did not cause persistent DAergic deficits, as assessed 7 to 8 days later. The impact of MDPV on striatal and hippocampal serotonergic assessments was minimal. Taken together, these data contribute to a growing pharmacological rubric for evaluating the ever-growing list of designer cathinone-related stimulants. The profile of MDPV compared with related psychostimulants is discussed. SIGNIFICANCE STATEMENT: Pharmacological characterization of the synthetic cathinone, 3,4-methylenedioxypyrovalerone (MDPV; commonly referred to as a "bath salt"), is critical for understanding the abuse liability and neurotoxic potential of this and related agents. Accordingly, the impact of MDPV on monoaminergic neurons is described and compared with that of related psychostimulants.


Asunto(s)
Benzodioxoles/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Drogas de Diseño/farmacología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Pirrolidinas/farmacología , Trastornos Relacionados con Sustancias/metabolismo , Proteínas de Transporte Vesicular de Monoaminas/metabolismo , Animales , Benzodioxoles/farmacocinética , Temperatura Corporal/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacocinética , Drogas de Diseño/farmacocinética , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Femenino , Masculino , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Pirrolidinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Cathinona Sintética
4.
Glob Chang Biol ; 26(12): 7268-7283, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33026137

RESUMEN

Globally, soils store two to three times as much carbon as currently resides in the atmosphere, and it is critical to understand how soil greenhouse gas (GHG) emissions and uptake will respond to ongoing climate change. In particular, the soil-to-atmosphere CO2 flux, commonly though imprecisely termed soil respiration (RS ), is one of the largest carbon fluxes in the Earth system. An increasing number of high-frequency RS measurements (typically, from an automated system with hourly sampling) have been made over the last two decades; an increasing number of methane measurements are being made with such systems as well. Such high frequency data are an invaluable resource for understanding GHG fluxes, but lack a central database or repository. Here we describe the lightweight, open-source COSORE (COntinuous SOil REspiration) database and software, that focuses on automated, continuous and long-term GHG flux datasets, and is intended to serve as a community resource for earth sciences, climate change syntheses and model evaluation. Contributed datasets are mapped to a single, consistent standard, with metadata on contributors, geographic location, measurement conditions and ancillary data. The design emphasizes the importance of reproducibility, scientific transparency and open access to data. While being oriented towards continuously measured RS , the database design accommodates other soil-atmosphere measurements (e.g. ecosystem respiration, chamber-measured net ecosystem exchange, methane fluxes) as well as experimental treatments (heterotrophic only, etc.). We give brief examples of the types of analyses possible using this new community resource and describe its accompanying R software package.


Asunto(s)
Gases de Efecto Invernadero , Atmósfera , Dióxido de Carbono/análisis , Ecosistema , Gases de Efecto Invernadero/análisis , Metano/análisis , Óxido Nitroso/análisis , Reproducibilidad de los Resultados , Respiración , Suelo
5.
Ecol Lett ; 22(12): 2049-2059, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31523909

RESUMEN

Vegetation canopy structure is a fundamental characteristic of terrestrial ecosystems that defines vegetation types and drives ecosystem functioning. We use the multivariate structural trait composition of vegetation canopies to classify ecosystems within a global canopy structure spectrum. Across the temperate forest sub-set of this spectrum, we assess gradients in canopy structural traits, characterise canopy structural types (CST) and evaluate drivers and functional consequences of canopy structural variation. We derive CSTs from multivariate canopy structure data, illustrating variation along three primary structural axes and resolution into six largely distinct and functionally relevant CSTs. Our results illustrate that within-ecosystem successional processes and disturbance legacies can produce variation in canopy structure similar to that associated with sub-continental variation in forest types and eco-climatic zones. The potential to classify ecosystems into CSTs based on suites of structural traits represents an important advance in understanding and modelling structure-function relationships in vegetated ecosystems.


Asunto(s)
Ecosistema , Árboles , Bosques , Fenotipo
6.
Molecules ; 24(23)2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31757061

RESUMEN

Diets rich in berries provide health benefits, however, the contribution of berry phytochemicals to the human metabolome is largely unknown. The present study aimed to establish the impact of berry phytochemicals on the human metabolome. A "systematic review strategy" was utilized to characterize the phytochemical composition of the berries most commonly consumed in the USA; (poly)phenols, primarily anthocyanins, comprised the majority of reported plant secondary metabolites. A reference standard library and tandem mass spectrometry (MS/MS) quantitative metabolomics methodology were developed and applied to serum/plasma samples from a blueberry and a strawberry intervention, revealing a diversity of benzoic, cinnamic, phenylacetic, 3-(phenyl)propanoic and hippuric acids, and benzyldehydes. 3-Phenylpropanoic, 2-hydroxybenzoic, and hippuric acid were highly abundant (mean > 1 µM). Few metabolites at concentrations above 100 nM changed significantly in either intervention. Significant intervention effects (P < 0.05) were observed for plasma/serum 2-hydroxybenzoic acid and hippuric acid in the blueberry intervention, and for 3-methoxyphenylacetic acid and 4-hydroxyphenylacetic acid in the strawberry intervention. However, significant within-group effects for change from baseline were prevalent, suggesting that high inter-individual variability precluded significant treatment effects. Berry consumption in general appears to cause a fluctuation in the pools of small molecule metabolites already present at baseline, rather than the appearance of unique berry-derived metabolites, which likely reflects the ubiquitous nature of (poly)phenols in the background diet.


Asunto(s)
Antocianinas/farmacocinética , Arándanos Azules (Planta)/química , Fragaria/química , Frutas/química , Metaboloma , Polifenoles/farmacocinética , Antocianinas/química , Humanos , Polifenoles/química
7.
New Phytol ; 219(4): 1188-1193, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29767850

RESUMEN

Contents Summary 1188 I. Introduction 1188 II. Forest aging and carbon storage 1189 III. Successional trends of NEP in northern deciduous forests 1190 IV. Mechanisms sustaining NEP in aging deciduous forests 1191 Acknowledgements 1192 References 1192 SUMMARY: Large areas of forestland in temperate North America, as well as in other parts of the world, are growing older and will soon transition into middle and then late successional stages exceeding 100 yr in age. These ecosystems have been important regional carbon sinks as they recovered from prior anthropogenic and natural disturbance, but their future sink strength, or annual rate of carbon storage, is in question. Ecosystem development theory predicts a steady decline in annual carbon storage as forests age, but newly available, direct measurements of forest net CO2 exchange challenge that prediction. In temperate deciduous forests, where moderate severity disturbance regimes now often prevail, there is little evidence for any marked decline in carbon storage rate during mid-succession. Rather, an increase in physical and biological complexity under these disturbance regimes may drive increases in resource-use efficiency and resource availability that help to maintain significant carbon storage in these forests well past the century mark. Conservation of aging deciduous forests may therefore sustain the terrestrial carbon sink, whilst providing other goods and services afforded by these biologically and structurally complex ecosystems.


Asunto(s)
Ciclo del Carbono , Bosques , Carbono/metabolismo , Dióxido de Carbono/metabolismo
8.
Br J Nutr ; 120(1): 23-32, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29729672

RESUMEN

n-3 Fatty acids are associated with better cardiovascular and cognitive health. However, the concentration of EPA, DPA and DHA in different plasma lipid pools differs and factors influencing this heterogeneity are poorly understood. Our aim was to evaluate the association of oily fish intake, sex, age, BMI and APOE genotype with concentrations of EPA, DPA and DHA in plasma phosphatidylcholine (PC), NEFA, cholesteryl esters (CE) and TAG. Healthy adults (148 male, 158 female, age 20-71 years) were recruited according to APOE genotype, sex and age. The fatty acid composition was determined by GC. Oily fish intake was positively associated with EPA in PC, CE and TAG, DPA in TAG, and DHA in all fractions (P≤0·008). There was a positive association between age and EPA in PC, CE and TAG, DPA in NEFA and CE, and DHA in PC and CE (P≤0·034). DPA was higher in TAG in males than females (P<0·001). There was a positive association between BMI and DPA and DHA in TAG (P<0·006 and 0·02, respectively). APOE genotype×sex interactions were observed: the APOE4 allele associated with higher EPA in males (P=0·002), and there was also evidence for higher DPA and DHA (P≤0·032). In conclusion, EPA, DPA and DHA in plasma lipids are associated with oily fish intake, sex, age, BMI and APOE genotype. Such insights may be used to better understand the link between plasma fatty acid profiles and dietary exposure and may influence intake recommendations across population subgroups.


Asunto(s)
Factores de Edad , Apolipoproteínas E/genética , Índice de Masa Corporal , Dieta , Ácidos Grasos Omega-3/sangre , Aceites de Pescado , Factores Sexuales , Adulto , Anciano , Alelos , Animales , Ésteres del Colesterol/sangre , Estudios Cruzados , Método Doble Ciego , Ácidos Grasos Insaturados/sangre , Femenino , Peces , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilcolinas/sangre , Reino Unido , Adulto Joven
9.
Proc Natl Acad Sci U S A ; 112(9): 2788-93, 2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25730847

RESUMEN

Terrestrial gross primary productivity (GPP) varies greatly over time and space. A better understanding of this variability is necessary for more accurate predictions of the future climate-carbon cycle feedback. Recent studies have suggested that variability in GPP is driven by a broad range of biotic and abiotic factors operating mainly through changes in vegetation phenology and physiological processes. However, it is still unclear how plant phenology and physiology can be integrated to explain the spatiotemporal variability of terrestrial GPP. Based on analyses of eddy-covariance and satellite-derived data, we decomposed annual terrestrial GPP into the length of the CO2 uptake period (CUP) and the seasonal maximal capacity of CO2 uptake (GPPmax). The product of CUP and GPPmax explained >90% of the temporal GPP variability in most areas of North America during 2000-2010 and the spatial GPP variation among globally distributed eddy flux tower sites. It also explained GPP response to the European heatwave in 2003 (r(2) = 0.90) and GPP recovery after a fire disturbance in South Dakota (r(2) = 0.88). Additional analysis of the eddy-covariance flux data shows that the interbiome variation in annual GPP is better explained by that in GPPmax than CUP. These findings indicate that terrestrial GPP is jointly controlled by ecosystem-level plant phenology and photosynthetic capacity, and greater understanding of GPPmax and CUP responses to environmental and biological variations will, thus, improve predictions of GPP over time and space.


Asunto(s)
Ecosistema , Modelos Biológicos , Fenómenos Fisiológicos de las Plantas , Plantas , South Dakota
10.
J Nutr ; 146(3): 516-23, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26817716

RESUMEN

BACKGROUND: Although many randomized controlled trials (RCTs) have examined the effects of the n-3 (ω-3) fatty acids eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) on blood pressure (BP) and vascular function, the majority have used doses of EPA+DHA of >3 g/d, which are unlikely to be achieved by dietary manipulation. OBJECTIVE: The objective was to examine, by using a retrospective analysis from a multicenter RCT, the impact of recommended EPA+DHA intakes achievable through diet on systolic and diastolic BPs and microvascular function in adults in the United Kingdom. METHODS: In a double-blind, placebo-controlled RCT, healthy men and women (n = 312) consumed a control oil or fish oil (FO) providing 0.7 or 1.8 g EPA+DHA/d, in random order, each for 8 wk. Fasting BP and microvascular function (using laser Doppler iontophoresis) were assessed and plasma collected for the quantification of markers of vascular function. Participants were retrospectively genotyped for the endothelial nitric oxide synthase (eNOS) rs1799983 variant. RESULTS: No effects of n-3 fatty acid treatment or any treatment × eNOS genotype interactions were evident in the group as a whole for any of the clinical or biochemical outcomes. Assessment of response according to hypertension status at baseline indicated a significant (P = 0.046) FO-induced reduction (mean: 5 mm Hg) in systolic BP, specifically in those with isolated systolic hypertension (n = 31). No dose response was observed. CONCLUSIONS: These findings indicate that in adults with isolated systolic hypertension, daily doses of EPA+DHA as low as 0.7 g show clinically meaningful BP reductions, which, at a population level, could be associated with lower cardiovascular disease risk. Confirmation of findings in an RCT in which participants are prospectively recruited on the basis of BP status is required to draw definite conclusions.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Aceites de Pescado/administración & dosificación , Hipertensión/sangre , Adulto , Índice de Masa Corporal , Estudios Cruzados , Dieta , Ácidos Docosahexaenoicos/sangre , Método Doble Ciego , Selectina E/sangre , Ácido Eicosapentaenoico/sangre , Femenino , Aceites de Pescado/sangre , Humanos , Molécula 1 de Adhesión Intercelular/sangre , Masculino , Persona de Mediana Edad , Óxido Nítrico Sintasa de Tipo III/genética , Selectina-P/sangre , Estudios Retrospectivos , Reino Unido , Molécula 1 de Adhesión Celular Vascular/sangre
11.
Ecology ; 96(9): 2478-87, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26594704

RESUMEN

The global carbon (C) balance is vulnerable to disturbances that alter terrestrial C storage. Disturbances to forests occur along a continuum of severity, from low-intensity disturbance causing the mortality or defoliation of only a subset of trees to severe stand- replacing disturbance that kills all trees; yet considerable uncertainty remains in how forest production changes across gradients of disturbance intensity. We used a gradient of tree mortality in an upper Great Lakes forest ecosystem to: (1) quantify how aboveground wood net primary production (ANPP,) responds to a range of disturbance severities; and (2) identify mechanisms supporting ANPPw resistance or resilience following moderate disturbance. We found that ANPPw declined nonlinearly with rising disturbance severity, remaining stable until >60% of the total tree basal area senesced. As upper canopy openness increased from disturbance, greater light availability to the subcanopy enhanced the leaf-level photosynthesis and growth of this formerly light-limited canopy stratum, compensating for upper canopy production losses and a reduction in total leaf area index (LAI). As a result, whole-ecosystem production efficiency (ANPPw/LAI) increased with rising disturbance severity, except in plots beyond the disturbance threshold. These findings provide a mechanistic explanation for a nonlinear relationship between ANPPw, and disturbance severity, in which the physiological and growth enhancement of undisturbed vegetation is proportional to the level of disturbance until a threshold is exceeded. Our results have important ecological and management implications, demonstrating that in some ecosystems moderate levels of disturbance minimally alter forest production.


Asunto(s)
Bosques , Modelos Biológicos , Plantas/clasificación , Árboles/fisiología , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Great Lakes Region , Actividades Humanas , Humanos , Michigan , Nitrógeno
12.
Am J Clin Nutr ; 119(3): 658-668, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38432713

RESUMEN

BACKGROUND: Anthocyanin and blueberry intakes positively associated with cognitive function in population-based studies and cognitive benefits in randomized controlled trials of adults with self-perceived or clinical cognitive dysfunction. To date, adults with metabolic syndrome (MetS) but without cognitive dysfunction are understudied. OBJECTIVES: Cognitive function, mood, alertness, and sleep quality were assessed as secondary end points in MetS participants, postprandially (>24 h) and following 6-mo blueberry intake. METHODS: A double-blind, randomized controlled trial was conducted, assessing the primary effect of consuming freeze-dried blueberry powder, compared against an isocaloric placebo, on cardiometabolic health >6 mo and a 24 h postprandial period (at baseline). In this secondary analysis of the main study, data from those completing mood, alertness, cognition, and sleep assessments are presented (i.e., n = 115 in the 6 mo study, n = 33 in the postprandial study), using the following: 1) Bond-Lader self-rated scores, 2) electronic cognitive battery (i.e., testing attention, working memory, episodic memory, speed of memory retrieval, executive function, and picture recognition), and 3) the Leeds Sleep Evaluation Questionnaire. Urinary and serum anthocyanin metabolites were quantified, and apolipoprotein E genotype status was determined. RESULTS: Postprandial self-rated calmness significantly improved after 1 cup of blueberries (P = 0.01; q = 0.04; with an 11.6% improvement compared with baseline between 0 and 24 h for the 1 cup group), but all other mood, sleep, and cognitive function parameters were unaffected after postprandial and 6-mo blueberries. Across the ½ and 1 cup groups, microbial metabolites of anthocyanins and chlorogenic acid (i.e., hydroxycinnamic acids, benzoic acids, phenylalanine derivatives, and hippuric acids) and catechin were associated with favorable chronic and postprandial memory, attention, executive function, and calmness. CONCLUSIONS: Although self-rated calmness improved postprandially, and significant cognition-metabolite associations were identified, our data did not support strong cognitive, mood, alertness, or sleep quality improvements in MetS participants after blueberry intervention. This trial was registered at clinicaltrials.gov as NCT02035592.


Asunto(s)
Arándanos Azules (Planta) , Síndrome Metabólico , Adulto , Humanos , Antocianinas , Periodo Posprandial , Cognición , Atención , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Ecol Lett ; 16(8): 1037-44, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23786499

RESUMEN

Shifting flowering phenology with rising temperatures is occurring worldwide, but the rarity of co-occurring long-term observational and temperature records has hindered the evaluation of phenological responsiveness in many species and across large spatial scales. We used herbarium specimens combined with historic temperature data to examine the impact of climate change on flowering trends in 141 species collected across 116,000 km(2) in north-central North America. On average, date of maximum flowering advanced 2.4 days °C(-1), although species-specific responses varied from - 13.5 to + 7.3 days °C(-1). Plant functional types exhibited distinct patterns of phenological responsiveness with significant differences between native and introduced species, among flowering seasons, and between wind- and biotically pollinated species. This study is the first to assess large-scale patterns of phenological responsiveness with broad species representation and is an important step towards understanding current and future impacts of climate change on species performance and biodiversity.


Asunto(s)
Cambio Climático , Monitoreo del Ambiente/métodos , Magnoliopsida/fisiología , Flores/crecimiento & desarrollo , Flores/fisiología , Magnoliopsida/crecimiento & desarrollo , Ohio , Polinización , Reproducción , Estaciones del Año , Temperatura , Factores de Tiempo
14.
J Nutr ; 143(4): 448-56, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23427331

RESUMEN

Scavenger receptor class B type I (SR-BI) and cluster determinant 36 (CD36) have been involved in cellular uptake of some provitamin A carotenoids. However, data are incomplete (e.g., there are no data on α-carotene), and it is not known whether genetic variants in their encoding genes can affect provitamin A carotenoid status. The objectives were 1) to assess the involvement of these scavenger receptors in cellular uptake of the main provitamin A carotenoids (i.e., ß-carotene, α-carotene, and ß-cryptoxanthin) as well as that of preformed vitamin A (i.e., retinol) and 2) to investigate the contribution of genetic variations in genes encoding these proteins to interindividual variations in plasma concentrations of provitamin A carotenoids. The involvement of SR-BI and CD36 in carotenoids and retinol cellular uptake was investigated in Caco-2 and human embryonic kidney (HEK) cell lines. The involvement of scavenger receptor class B type I (SCARB1) and CD36 genetic variants on plasma concentrations of provitamin A carotenoids was assessed by association studies in 3 independent populations. Cell experiments suggested the involvement of both proteins in cellular uptake of provitamin A carotenoids but not in that of retinol. Association studies showed that several plasma provitamin A carotenoid concentrations were significantly different (P < 0.0083) between participants who bore different genotypes at single nucleotide polymorphisms and haplotypes in CD36 and SCARB1. In conclusion, SR-BI and CD36 are involved in cellular uptake of provitamin A carotenoids, and genetic variations in their encoding genes may modulate plasma concentrations of provitamin A carotenoids at a population level.


Asunto(s)
Antígenos CD36/genética , Antígenos CD36/fisiología , Carotenoides/sangre , Carotenoides/metabolismo , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/fisiología , Adolescente , Células CACO-2 , Estudios Transversales , Criptoxantinas , Femenino , Variación Genética , Genotipo , Células HEK293 , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales , Vitamina A/metabolismo , Xantófilas/sangre , Xantófilas/metabolismo , beta Caroteno/sangre , beta Caroteno/metabolismo
15.
Ecol Appl ; 23(5): 1202-15, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23967586

RESUMEN

Carbon (C) uptake rates in many forests are sustained, or decline only briefly, following disturbances that partially defoliate the canopy. The mechanisms supporting such functional resistance to moderate forest disturbance are largely unknown. We used a large-scale experiment, in which > 6700 Populus (aspen) and Betula (birch) trees were stem-girdled within a 39-ha area, to identify mechanisms sustaining C uptake through partial canopy defoliation. The Forest Accelerated Succession Experiment in northern Michigan, USA, employs a suite of C-cycling measurements within paired treatment and control meteorological flux tower footprints. We found that enhancement of canopy light-use efficiency and maintenance of light absorption maintained net ecosystem production (NEP) and aboveground wood net primary production (NPP) when leaf-area index (LAI) of the treatment forest temporarily declined by nearly half its maximum value. In the year following peak defoliation, redistribution of nitrogen (N) in the treatment forest from senescent early successional aspen and birch to non-girdled later successional species facilitated the recovery of total LAI to pre-disturbance levels. Sustained canopy physiological competency following disturbance coincided with a downward shift in maximum canopy height, indicating that compensatory photosynthetic C uptake by undisturbed, later successional subdominant and subcanopy vegetation supported C-uptake resistance to disturbance. These findings have implications for ecosystem management and modeling, demonstrating that forests may tolerate considerable leaf-area losses without diminishing rates of C uptake. We conclude that the resistance of C uptake to moderate disturbance depends not only on replacement of lost leaf area, but also on rapid compensatory photosynthetic C uptake during defoliation by emerging later successional species.


Asunto(s)
Carbono/química , Carbono/metabolismo , Ecosistema , Árboles , Betula , Dióxido de Carbono/metabolismo , Monitoreo del Ambiente , Great Lakes Region , Actividades Humanas , Humanos , Michigan , Nitrógeno , Hojas de la Planta , Transpiración de Plantas , Populus , Factores de Tiempo
16.
PLoS One ; 18(3): e0282635, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36867631

RESUMEN

Shifts in the timing of key leaf phenological events including budburst, foliage coloration, and leaf fall have been observed worldwide and are consistent with climate warming. Quantifying changes in growing season length (GSL) because of shifts in both spring and autumn leaf phenology is crucial for modeling annual net ecosystem carbon uptake. However, a lack of long-term autumn phenology datasets has prevented assessment of these growing season level changes. We investigated shifts in growing season length, budburst, foliage coloration, and leaf fall over the past century in seven native hardwood species using a historic leaf phenology dataset collected in Wauseon, OH from 1883-1912 paired with contemporary observations. Using long-term meteorological data, we investigated temperature and precipitation trends over 130 years. Finally, we correlated spring and fall phenophases with monthly temperature and precipitation variables from the twelve months preceding that phenophase using historical meteorological data. We found significant extension of growing season length over the past century in five of the seven study species (ANOVA, p < 0.05) which resulted primarily from delayed foliage coloration rather than from earlier budburst in contrast to the few other studies assessing total GSL change. Our results suggest that most of the leaf phenological studies that investigate only budburst are disregarding crucial information about the end of the growing season that is essential for accurately predicting the effects of climate change in mixed-species temperate deciduous forests.


Asunto(s)
Ecosistema , Hojas de la Planta , Estaciones del Año , América Central , América del Norte
17.
Br J Nutr ; 107(12): 1833-44, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22017999

RESUMEN

Reducing the prevalence of fat-rich, energy-dense diets is a public health priority. The present parallel-designed randomised study compared three interventions aimed to increase intakes of low-fat starchy foods and to reduce fat intakes among 589 individuals from 169 families in the Family Food and Health Project (FFHP). Intervention A was education only, intervention B provided 'cook and eat' sessions only, whereas intervention C included personalised goal setting, 'cook and eat' and education. Diet was assessed at baseline (T0) and at 3 months (T1), 6 months (T2) and 18 months (T3) post-intervention. Retention rates were 75 % at T1, 63 % at T2 and 40 % at T3. ANCOVA (baseline intake as covariate) was assessed between intervention differences at T1, T2 and T3. At T1, individuals in intervention C consumed less fat (P = 0·02) and more total carbohydrate (P = 0·001), starch (P = 0·04) vitamin C (P = 0·002) and NSP (P = 0·01) than those in intervention A. Whereas similar dietary intakes were reported across interventions at T2, participants in intervention C had less energy-dense diets that contained more NSP and vitamin C at T3 than intervention A (P < 0·0001, P = 0·002 and P = 0·01, respectively). Across all intervention groups, the more socially deprived participants in the FFHP (n 119) consumed less fat (P = 0·01) and more total carbohydrate (P = 0·02) at T2 than the least socially deprived (n 240). These data demonstrate the importance of personalised goal setting to translate knowledge and practical cooking skills into healthier food choices, suggesting that low-fat starchy food-focused interventions may be effective in reducing fat intake.


Asunto(s)
Dieta , Ingestión de Energía , Familia , Conducta Alimentaria , Objetivos , Promoción de la Salud/métodos , Adolescente , Adulto , Análisis de Varianza , Ácido Ascórbico/administración & dosificación , Niño , Preescolar , Culinaria , Dieta con Restricción de Grasas , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Educación en Salud , Humanos , Almidón/administración & dosificación
18.
Am J Community Psychol ; 49(3-4): 517-25, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22543718

RESUMEN

This article describes how a system of care operated by a county government agency used a fiscal crisis as the opportunity to reform its children's system. A cross-system response to the crisis is outlined that includes a system of care framework coupled with a business model, inter-departmental collaboration and leadership, the use of strategic reinvestment strategies, and a quality improvement system that focuses on key indicators. Implementation of the system change is described with a specific focus on cross-system entry points, financing strategies that re-allocate funds from deep-end programs to community-based services, and management oversight through the use of performance indicators to monitor and support effectiveness. This article examines the results of the system change, including the diversion of youth from system penetration, the reduction in residential treatment bed days, the re-allocation of these savings to community-based services, and the outcomes of children who were diverted from residential care and served in the community. The article offers a number of recommendations for other communities contemplating system change.


Asunto(s)
Prestación Integrada de Atención de Salud/economía , Prestación Integrada de Atención de Salud/organización & administración , Administración Financiera/organización & administración , Modelos Organizacionales , Indicadores de Calidad de la Atención de Salud , Adolescente , Niño , Preescolar , Centros Comunitarios de Salud Mental/economía , Centros Comunitarios de Salud Mental/organización & administración , Recesión Económica , Humanos , New York , Estudios de Casos Organizacionales
19.
Clin Nutr ; 41(1): 165-176, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34883305

RESUMEN

BACKGROUND & AIMS: Whilst the cardioprotective effects of blueberry intake have been shown in prospective studies and short-term randomized controlled trials (RCTs), it is unknown whether anthocyanin-rich blueberries can attenuate the postprandial, cardiometabolic dysfunction which follows energy-dense food intakes; especially in at-risk populations. We therefore examined whether adding blueberries to a high-fat/high-sugar meal affected the postprandial cardiometabolic response over 24 h. METHODS: A parallel, double-blind RCT (n = 45; age 63.4 ± 7.4 years; 64% male; BMI 31.4 ± 3.1 kg/m2) was conducted in participants with metabolic syndrome. After baseline assessments, an energy-dense drink (969 Kcals, 64.5 g fat, 84.5 g carbohydrate, 17.9 g protein) was consumed with either 26 g (freeze-dried) blueberries (equivalent to 1 cup/150 g fresh blueberries) or 26 g isocaloric matched placebo. Repeat blood samples (30, 60, 90, 120, 180, 360 min and 24 h), a 24 h urine collection and vascular measures (at 3, 6, and 24 h) were performed. Insulin and glucose, lipoprotein levels, endothelial function (flow mediated dilatation (FMD)), aortic and systemic arterial stiffness (pulse wave velocity (PWV), Augmentation Index (AIx) respectively), blood pressure (BP), and anthocyanin metabolism (serum and 24 h urine) were assessed. RESULTS: Blueberries favorably affected postprandial (0-24 h) concentrations of glucose (p < 0.001), insulin (p < 0.01), total cholesterol (p = 0.04), HDL-C, large HDL particles (L-HDL-P) (both p < 0.01), extra-large HDL particles (XL-HDL-P; p = 0.04) and Apo-A1 (p = 0.01), but not LDL-C, TG, or Apo-B. After a transient higher peak glucose concentration at 1 h after blueberry intake ([8.2 mmol/L, 95%CI: 7.7, 8.8] vs placebo [6.9 mmol/L, 95%CI: 6.4, 7.4]; p = 0.001), blueberries significantly attenuated 3 h glucose ([4.3 mmol/L, 95%CI: 3.8, 4.8] vs placebo [5.1 mmol/L, 95%CI: 4.6, 5.6]; p = 0.03) and insulin concentrations (blueberry: [23.4 pmol/L, 95%CI: 15.4, 31.3] vs placebo [52.9 pmol/L, 95%CI: 41.0, 64.8]; p = 0.0001). Blueberries also improved HDL-C ([1.12 mmol/L, 95%CI: 1.06, 1.19] vs placebo [1.08 mmol/L, 95%CI: 1.02, 1.14]; p = 0.04) at 90 min and XL-HDLP levels ([0.38 × 10-6, 95%CI: 0.35, 0.42] vs placebo [0.35 × 10-6, 95%CI: 0.32, 0.39]; p = 0.02) at 3 h. Likewise, significant improvements were observed 6 h after blueberries for HDL-C ([1.17 mmol/L, 95%CI: 1.11, 1.24] vs placebo [1.10 mmol/L, 95%CI: 1.03, 1.16]; p < 0.001), Apo-A1 ([1.37 mmol/L, 95%CI: 1.32, 1.41] vs placebo [1.31 mmol/L, 95%CI: 1.27, 1.35]; p = 0.003), L-HDLP ([0.70 × 10-6, 95%CI: 0.60, 0.81] vs placebo [0.59 × 10-6, 95%CI: 0.50, 0.68]; p = 0.003) and XL-HDLP ([0.44 × 10-6, 95%CI: 0.40, 0.48] vs placebo [0.40 × 10-6, 95%CI: 0.36, 0.44]; p < 0.001). Similarly, total cholesterol levels were significantly lower 24 h after blueberries ([4.9 mmol/L, 95%CI: 4.6, 5.1] vs placebo [5.0 mmol/L, 95%CI: 4.8, 5.3]; p = 0.04). Conversely, no effects were observed for FMD, PWV, AIx and BP. As anticipated, total anthocyanin-derived phenolic acid metabolite concentrations significantly increased in the 24 h after blueberry intake; especially hippuric acid (6-7-fold serum increase, 10-fold urinary increase). In exploratory analysis, a range of serum/urine metabolites were associated with favorable changes in total cholesterol, HDL-C, XL-HDLP and Apo-A1 (R = 0.43 to 0.50). CONCLUSIONS: For the first time, in an at-risk population, we show that single-exposure to the equivalent of 1 cup blueberries (provided as freeze-dried powder) attenuates the deleterious postprandial effects of consuming an energy-dense high-fat/high-sugar meal over 24 h; reducing insulinaemia and glucose levels, lowering cholesterol, and improving HDL-C, fractions of HDL-P and Apo-A1. Consequently, intake of anthocyanin-rich blueberries may reduce the acute cardiometabolic burden of energy-dense meals. CLINICAL TRIAL REGISTRY: NCT02035592 at www.clinicaltrials.gov.


Asunto(s)
Antocianinas/administración & dosificación , Arándanos Azules (Planta) , Ingestión de Energía/efectos de los fármacos , Comidas/efectos de los fármacos , Síndrome Metabólico/metabolismo , Anciano , Antocianinas/sangre , Antocianinas/orina , Glucemia/metabolismo , Presión Sanguínea/efectos de los fármacos , Dieta de Carga de Carbohidratos/efectos adversos , Dieta Alta en Grasa/efectos adversos , Método Doble Ciego , Endotelio Vascular/efectos de los fármacos , Femenino , Humanos , Insulina/sangre , Lipoproteínas/sangre , Masculino , Persona de Mediana Edad , Periodo Posprandial/efectos de los fármacos , Análisis de la Onda del Pulso , Rigidez Vascular/efectos de los fármacos
20.
Ecol Appl ; 21(4): 1189-201, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21774423

RESUMEN

Temperate forest soils store globally significant amounts of carbon (C) and nitrogen (N). Understanding how soil pools of these two elements change in response to disturbance and management is critical to maintaining ecosystem services such as forest productivity, greenhouse gas mitigation, and water resource protection. Fire is one of the principal disturbances acting on forest soil C and N storage and is also the subject of enormous management efforts. In the present article, we use meta-analysis to quantify fire effects on temperate forest soil C and N storage. Across a combined total of 468 soil C and N response ratios from 57 publications (concentrations and pool sizes), fire had significant overall effects on soil C (-26%) and soil N (-22%). The impacts of fire on forest floors were significantly different from its effects on mineral soils. Fires reduced forest floor C and N storage (pool sizes only) by an average of 59% and 50%, respectively, but the concentrations of these two elements did not change. Prescribed fires caused smaller reductions in forest floor C and N storage (-46% and -35%) than wildfires (-67% and -69%), and the presence of hardwoods also mitigated fire impacts. Burned forest floors recovered their C and N pools in an average of 128 and 103 years, respectively. Among mineral soils, there were no significant changes in C or N storage, but C and N concentrations declined significantly (-11% and -12%, respectively). Mineral soil C and N concentrations were significantly affected by fire type, with no change following prescribed burns, but significant reductions in response to wildfires. Geographic variation in fire effects on mineral soil C and N storage underscores the need for region-specific fire management plans, and the role of fire type in mediating C and N shifts (especially in the forest floor) indicates that averting wildfires through prescribed burning is desirable from a soils perspective.


Asunto(s)
Carbono/química , Incendios , Nitrógeno/química , Suelo/química , Árboles , Ecosistema
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