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1.
Front Integr Neurosci ; 17: 1145744, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37181865

RESUMEN

Systems Thinking (ST) can be defined as a mental construct that recognises patterns and connections in a particular complex system to make the "best decision" possible. In the field of sustainable agriculture and climate change, higher degrees of ST are assumed to be associated with more successful adaptation strategies under changing conditions, and "better" environmental decision making in a number of environmental and cultural settings. Future climate change scenarios highlight the negative effects on agricultural productivity worldwide, particularly in low-income countries (LICs) situated in the Global South. Alongside this, current measures of ST are limited by their reliance on recall, and are prone to possible measurement errors. Using Climate-Smart Agriculture (CSA), as an example case study, in this article we explore: (i) ST from a social science perspective; (ii) cognitive neuroscience tools that could be used to explore ST abilities in the context of LICs; (iii) an exploration of the possible correlates of systems thinking: observational learning, prospective thinking/memory and the theory of planned behaviour and (iv) a proposed theory of change highlighting the integration of social science frameworks and a cognitive neuroscience perspective. We find, recent advancements in the field of cognitive neuroscience such as Near-Infrared Spectroscopy (NIRS) provide exciting potential to explore previously hidden forms of cognition, especially in a low-income country/field setting; improving our understanding of environmental decision-making and the ability to more accurately test more complex hypotheses where access to laboratory studies is severely limited. We highlight that ST may correlate with other key aspects involved in environmental decision-making and posit motivating farmers via specific brain networks would: (a) enhance understanding of CSA practices (e.g., via the frontoparietal network extending from the dorsolateral prefrontal cortex (DLPFC) to the parietal cortex (PC) a control hub involved in ST and observational learning) such as tailoring training towards developing improved ST abilities among farmers and involving observational learning more explicitly and (b) motivate farmers to use such practices [e.g., via the network between the DLPFC and nucleus accumbens (NAc)] which mediates reward processing and motivation by focussing on a reward/emotion to engage farmers. Finally, our proposed interdisciplinary theory of change can be used as a starting point to encourage discussion and guide future research in this space.

2.
Ann N Y Acad Sci ; 1517(1): 154-166, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36036193

RESUMEN

Nutrient enriched crops (NECs) were developed through biofortification as a tool to reach the world's most vulnerable. The delivery model developed by HarvestPlus for the scaling of NECs relies on commercial demand from food businesses and consumers, coupled with the ability to promote and market foods that comply with legislation. This review of standards, regulations, and laws across the value chain in 20 countries demonstrates that existing provisions for food labeling are sufficient to carry out sales and marketing of foods made from conventionally bred NECs. The term biofortification is not necessary to create demand and, potentially, is counterproductive. Promoting the natural source of vitamins and minerals and relevant nutrition claims is the most effective and simple way to signpost healthier products to consumers. Until 2021, it was not possible to distinguish NECs at the grain level from the market standard. The development of a globally relevant Publicly Available Specification allows traders to demand grains that offer a substantial increase in zinc, iron, or vitamin A. Addressing this gap at the grain level ensures that standards and regulations are available end-to-end in the food supply chain providing the enabling environment for the rapid scale of NECs.


Asunto(s)
Biofortificación , Alimentos Fortificados , Humanos , Productos Agrícolas , Nutrientes , Vitamina A
3.
Front Pharmacol ; 8: 678, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29204115

RESUMEN

Several studies have indicated a chronic cognitive enhancing effect of Bacopa monnieri across different ages and cognitive impairment associated with vitamin and mineral deficiencies in children. Therefore, we investigated the effects of 4-month supplementation with a combination of B. monnieri extract and multiple micronutrients on cognitive functions in Indian school children aged 7-12 years. This was a randomized, double-blind, parallel design, single-center study in which 300 children were randomized to receive a beverage either fortified with B. monnieri and multiple micronutrients ("fortified") or a non-fortified isocaloric equivalent ("control") twice-daily for 4 months. Cognitive function was assessed by the Cambridge Neuropsychological Automated Test Battery (CANTAB) administered at baseline, Day 60 and Day 121. The primary endpoint was change in short-term memory (working memory) from baseline in subjects receiving "fortified" vs. "control" beverages after 4 months. Secondary endpoints included sustained attention, episodic memory, and executive function. The "fortified" beverage did not significantly improve short-term memory or any of the secondary outcomes tested relative to the "control" beverage. However, the spatial working memory "strategy" score showed significant improvement on Day 60 (difference between groups in change from baseline: -0.55; p < 0.05), but not on Day 121 due to the active intervention. Study products were well-tolerated. Reasons for these unexpected findings are discussed.

4.
PLoS One ; 12(8): e0182984, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28832626

RESUMEN

Bacopa monnieri is a plant used as a nootropic in Ayurveda, a 5000-year-old system of traditional Indian medicine. Although both animal and clinical studies supported its role as a memory enhancer, the molecular and cellular mechanism underlying Bacopa's nootropic action are not understood. In this study, we used deep sequencing (RNA-Seq) to identify the transcriptome changes upon Bacopa treatment on SH-SY5Y human neuroblastoma cells. We identified several genes whose expression levels were regulated by Bacopa. Biostatistical analysis of the RNA-Seq data identified biological pathways and molecular functions that were regulated by Bacopa, including regulation of mRNA translation and transmembrane transport, responses to oxidative stress and protein misfolding. Pathway analysis using the Ingenuity platform suggested that Bacopa may protect against brain damage and improve brain development. These newly identified molecular and cellular determinants may contribute to the nootropic action of Bacopa and open up a new direction of investigation into its mechanism of action.


Asunto(s)
Bacopa/fisiología , Regulación Neoplásica de la Expresión Génica , Neuroblastoma/metabolismo , Diferenciación Celular , Línea Celular Tumoral , Humanos , Neuroblastoma/patología , ARN Mensajero/genética , Análisis de Secuencia de ARN
5.
J Gen Physiol ; 134(5): 385-96, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19858358

RESUMEN

The G(q)-coupled tachykinin receptor (neurokinin-1 receptor [NK-1R]) modulates N-type Ca(2+) channel (Ca(V)2.2 or N channel) activity at two distinct sites by a pathway involving a lipid metabolite, most likely arachidonic acid (AA). In another study published in this issue (Heneghan et al. 2009. J. Gen Physiol. doi:10.1085/jgp.200910203), we found that the form of modulation observed depends on which Ca(V)beta is coexpressed with Ca(V)2.2. When palmitoylated Ca(V)beta2a is coexpressed, activation of NK-1Rs by substance P (SP) enhances N current. In contrast, when Ca(V)beta3 is coexpressed, SP inhibits N current. However, exogenously applied palmitic acid minimizes this inhibition. These findings suggested that the palmitoyl groups of Ca(V)beta2a may occupy an inhibitory site on Ca(V)2.2 or prevent AA from interacting with that site, thereby minimizing inhibition. If so, changing the orientation of Ca(V)beta2a relative to Ca(V)2.2 may displace the palmitoyl groups and prevent them from antagonizing AA's actions, thereby allowing inhibition even in the presence of Ca(V)beta2a. In this study, we tested this hypothesis by deleting one (Bdel1) or two (Bdel2) amino acids proximal to the alpha interacting domain (AID) of Ca(V)2.2's I-II linker. Ca(V)betas bind tightly to the AID, whereas the rigid region proximal to the AID is thought to couple Ca(V)beta's movements to Ca(V)2.2 gating. Although Bdel1/beta2a currents exhibited more variable enhancement by SP, Bdel2/beta2a current enhancement was lost at all voltages. Instead, inhibition was observed that matched the profile of N-current inhibition from Ca(V)2.2 coexpressed with Ca(V)beta3. Moreover, adding back exogenous palmitic acid minimized inhibition of Bdel2/beta2a currents, suggesting that when palmitoylated Ca(V)beta2a is sufficiently displaced, endogenously released AA can bind to the inhibitory site. These findings support our previous hypothesis that Ca(V)beta2a's palmitoyl groups directly interact with an inhibitory site on Ca(V)2.2 to block N-current inhibition by SP.


Asunto(s)
Canales de Calcio Tipo N/metabolismo , Receptores de Taquicininas/metabolismo , Animales , Canales de Calcio Tipo N/química , Células Cultivadas , Conductividad Eléctrica , Humanos , Lipoilación , Modelos Biológicos , Ácido Palmítico/farmacología , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Ratas
6.
J Gen Physiol ; 134(5): 369-84, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19858357

RESUMEN

In superior cervical ganglion (SCG) neurons, stimulation of M(1) receptors (M(1)Rs) produces a distinct pattern of modulation of N-type calcium (N-) channel activity, enhancing currents elicited with negative test potentials and inhibiting currents elicited with positive test potentials. Exogenously applied arachidonic acid (AA) reproduces this profile of modulation, suggesting AA functions as a downstream messenger of M(1)Rs. In addition, techniques that diminish AA's concentration during M(1)R stimulation minimize N-current modulation. However, other studies suggest depletion of phosphatidylinositol-4,5-bisphosphate during M(1)R stimulation suffices to elicit modulation. In this study, we used an expression system to examine the physiological mechanisms regulating modulation. We found the beta subunit (Ca(V)beta) acts as a molecular switch regulating whether modulation results in enhancement or inhibition. In human embryonic kidney 293 cells, stimulation of M(1)Rs or neurokinin-1 receptors (NK-1Rs) inhibited activity of N channels formed by Ca(V)2.2 and coexpressed with Ca(V)beta1b, Ca(V)beta3, or Ca(V)beta4 but enhanced activity of N channels containing Ca(V)beta2a. Exogenously applied AA produced the same pattern of modulation. Coexpression of Ca(V)beta2a, Ca(V)beta3, and Ca(V)beta4 recapitulated the modulatory response previously seen in SCG neurons, implying heterogeneous association of Ca(V)beta with Ca(V)2.2. Further experiments with mutated, chimeric Ca(V)beta subunits and free palmitic acid revealed that palmitoylation of Ca(V)beta2a is essential for loss of inhibition. The data presented here fit a model in which Ca(V)beta2a blocks inhibition, thus unmasking enhancement. Our discovery that the presence or absence of palmitoylated Ca(V)beta2a toggles M(1)R- or NK-1R-mediated modulation of N current between enhancement and inhibition identifies a novel role for palmitoylation. Moreover, these findings predict that at synapses, modulation of N-channel activity by M(1)Rs or NK-1Rs will fluctuate between enhancement and inhibition based on the presence of palmitoylated Ca(V)beta2a.


Asunto(s)
Canales de Calcio Tipo N/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Subunidades de Proteína/metabolismo , Receptor Muscarínico M1/metabolismo , Animales , Calcio/metabolismo , Células Cultivadas , Conductividad Eléctrica , Humanos , Potenciales de la Membrana , Modelos Biológicos , Ratas , Ganglio Cervical Superior/metabolismo
7.
Cell Calcium ; 45(6): 589-601, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19419761

RESUMEN

Great skepticism has surrounded the question of whether modulation of voltage-gated Ca(2+) channels (VGCCs) by the polyunsaturated free fatty acid arachidonic acid (AA) has any physiological basis. Here we synthesize findings from studies of both native and recombinant channels where micromolar concentrations of AA consistently inhibit both native and recombinant activity by stabilizing VGCCs in one or more closed states. Structural requirements for these inhibitory actions include a chain length of at least 18 carbons and multiple double bonds located near the fatty acid's carboxy terminus. Acting at a second site, AA increases the rate of VGCC activation kinetics, and in Ca(V)2.2 channels, increases current amplitude. We present evidence that phosphatidylinositol 4,5-bisphosphate (PIP(2)), a palmitoylated accessory subunit (beta(2a)) of VGCCs and AA appear to have overlapping sites of action giving rise to complex channel behavior. Their actions converge in a physiologically relevant manner during muscarinic modulation of VGCCs. We speculate that M(1) muscarinic receptors may stimulate multiple lipases to break down the PIP(2) associated with VGCCs and leave PIP(2)'s freed fatty acid tails bound to the channels to confer modulation. This unexpectedly simple scheme gives rise to unanticipated predictions and redirects thinking about lipid regulation of VGCCs.


Asunto(s)
Canales de Calcio/metabolismo , Lípidos/fisiología , Ácido Araquidónico/metabolismo , Calcio/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipasas A2 Citosólicas/metabolismo , Receptores Muscarínicos/metabolismo
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