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1.
Environ Monit Assess ; 194(9): 648, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931859

RESUMO

Rice cultivation is a major source of methane (CH4) emissions. Intermittent irrigation systems in rice cultivation, such as the mid-season drainage (MSD), are effective strategies to mitigate CH4 emissions during the growing season, though the reduction rates are variable and dependent on the crop context. Aeration periods induce alteration of soil CH4 dynamics that can be prolonged after flooding recovery. However, whether these changes persist beyond the growing season remains underexplored. A field experiment was conducted in Spain to study the effect of MSD implemented during the rice growing season on greenhouse gas (GHG) emissions in relation to the standard permanently flooded water management (PFL). Specifically, the study aimed at (1) assessing the CH4 mitigation capacity of MSD in the studied area and (2) testing the hypothesis that the mitigating effect of MSD can be extended into the following winter flooded fallow season. Year-round GHG sampling was conducted, seasonal and annual cumulative emissions of CH4 and N2O as well as the global warming potential were calculated, and grain yield was measured. MSD reduced growing season CH4 emissions by ca. 80% without yield penalties. During the flooded fallow season, MSD reduced CH4 emissions by ca. 60%, despite both fields being permanently flooded. The novelty of our observations lies in the amplified mitigation capacity of MSD by extending the CH4 mitigation effect to the following flooded winter fallow season. This finding becomes especially relevant in rice systems with flooded winter fallow season given the large contribution of this season to the annual CH4 emissions.


Assuntos
Gases de Efeito Estufa , Oryza , Agricultura , Monitoramento Ambiental , Metano/análise , Óxido Nitroso/análise , Estações do Ano , Solo , Espanha
2.
iScience ; 25(6): 104445, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35634575

RESUMO

Probiotics have been suggested as one solution to counter detrimental health effects by SARS-CoV-2; however, data so far is scarce. We tested the effect of two probiotic consortia, OL-1 and OL-2, against SARS-CoV-2 in ferrets and assessed their effect on cytokine production and transcriptome in a human monocyte-derived macrophage (Mf) and dendritic cell (DC) model. The results showed that the consortia significantly reduced the viral load, modulated immune response, and regulated viral receptor expression in ferrets compared to placebo. In the human Mf and DC model, OL-1 and OL-2-induced cytokine production and genes related to SARS-CoV-2 antiviral immunity. The study results indicate that probiotic stimulation of the ferret immune system leads to improved antiviral immunity against SARS-COV-2, and the genes and cytokines associated with anti-SARS-CoV-2 immunity are stimulated in human immune cells in vitro. The effect of the consortia against SARS-CoV-2 warrants further investigations in human clinical trials.

3.
J Berry Res ; 7(3): 203-216, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28979610

RESUMO

OBJECT: Improved precision fertilization by introducing sensors and remote control to secure fruit yield and reduce nutrient leaching in soil culture. MATERIAL AND METHODS: We broadcasted before bedding and mulching 50 g m-2 of a multi-mineral fertilizer. Beds had two plant rows 20 cm apart, with plant distance of 25 cm. Experimental design was split plot with three replications and three treatments. Treatments: fertigation in large plots, cultivar in small plots and year. RESULTS: Plant development in the establishing year had no benefit of fertigation in addition to fertilizer given before bedding. When the yield is 3 kg m-2 a nutrient solution of 6 g N m-2 gave highest yield, using 4 g m-2 from two weeks before harvest and during harvest. 'Florence' and 'Sonata' developed well; however, 'Florence' had mildew on fruits in the last cropping year. 'Korona' presented well the first cropping year, but grew small fruits heavily infested by mildew in the last cropping year. CONCLUSION: Fertilization had effect on fruit yield. It is discussed how a fertilization schedule for the establishment year and cropping years can be adapted to plant development stages. Mildew infestation on fruits was dependent of cultivar and fertilization. Introducing sensors for recording of growth factors and in situ ion-levels of soil water nutrients, proved valuable.

4.
Eur J Pharmacol ; 655(1-3): 52-8, 2011 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-21262222

RESUMO

Nicotine dependence is maintained by the aversive, depression-like effects of nicotine withdrawal and the rewarding effects of acute nicotine. GABA(B) receptor antagonists exhibit antidepressant-like effects in rodents, whereas GABA(B) receptor agonists attenuate the rewarding effects of nicotine. Recent studies with GABA(B) receptor positive modulators showed that these compounds represent potentially improved medications for the treatment of nicotine dependence because of fewer side-effects than GABA(B) receptor agonists. Thus, GABA(B) receptor agonists and antagonists, and GABA(B) receptor positive modulators may have efficacy as smoking cessation aids by targeting different aspects of nicotine dependence and withdrawal. The present study assessed the effects of the GABA(B) receptor agonist CGP44532, the GABA(B) receptor antagonist CGP56433A, and the GABA(B) receptor positive modulator BHF177 on the anhedonic aspects of nicotine withdrawal. Rats were prepared with stimulating electrodes in the posterior lateral hypothalamus. After establishing stable intracranial self-stimulation (ICSS) thresholds, rats were prepared with subcutaneous osmotic minipumps delivering either nicotine or saline for 7 or 14days. ICSS thresholds were assessed 6h post-pump removal. Thirty hours after pump removal, CGP44532, CGP56433A, and BHF177 were administered 30min prior to ICSS testing. Both GABA(B) receptor activation (CGP44532 and BHF177) and blockade (CGP56433A) elevated ICSS thresholds in all groups, resulting in exacerbated effects of nicotine withdrawal in the nicotine-treated groups. These similar effects of GABA(B) receptor activation and blockade on the anhedonic depression-like aspects of nicotine withdrawal were surprising and perhaps reflect differential efficacy of these compounds at presynaptic hetero- and autoreceptors, as well as postsynaptic, GABA(B) receptors.


Assuntos
Depressão/induzido quimicamente , Agonistas dos Receptores de GABA-B/farmacologia , Antagonistas de Receptores de GABA-B/farmacologia , Nicotina/efeitos adversos , Receptores de GABA-B/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Animais , Benzoatos/farmacologia , Depressão/metabolismo , Sinergismo Farmacológico , Masculino , Nicotina/administração & dosagem , Ácidos Fosfínicos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Ratos , Ratos Wistar , Recompensa , Autoestimulação/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/etiologia , Ácido gama-Aminobutírico/análogos & derivados , Ácido gama-Aminobutírico/farmacologia
5.
Psychopharmacology (Berl) ; 215(1): 117-28, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21181127

RESUMO

RATIONALE: γ-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain and is implicated in the modulation of central reward processes. Acute or chronic administration of GABA(B) receptor agonists or positive modulators decreased self-administration of various drugs of abuse. Furthermore, GABA(B) receptor agonists inhibited cue-induced reinstatement of nicotine- and cocaine-seeking behavior. Because of their fewer adverse side effects compared with GABA(B) receptor agonists, GABA(B) receptor positive modulators are potentially improved therapeutic compounds for the treatment of drug dependence compared with agonists. OBJECTIVES AND METHODS: We examined whether the acute effects of the GABA(B) receptor positive modulator N-[(1R,2R,4S)-bicyclo[2.2.1]hept-2-yl]-2-methyl-5-[4-(trifluoromethyl)phenyl]-4-pyrimidinamine (BHF177) on nicotine self-administration and food-maintained responding under a fixed-ratio 5 schedule of reinforcement were maintained after repeated administration. The effects of acute BHF177 administration on cue-induced nicotine- and food-seeking behavior, a putative animal model of relapse, were also examined. RESULTS: Repeated administration of BHF177 for 14 days decreased nicotine self-administration, with small tolerance observed during the last 7 days of treatment, whereas BHF177 minimally affected food-maintained responding. Acute BHF177 administration dose-dependently blocked cue-induced reinstatement of nicotine-, but not food-, seeking behavior after a 10-day extinction period. CONCLUSIONS: These results showed that BHF177 selectively blocked nicotine self-administration and prevented cue-induced reinstatement of nicotine seeking, with minimal effects on responding for food and no effect on cue-induced reinstatement of food seeking. Thus, GABA(B) receptor positive modulators could be useful therapeutics for the treatment of different aspects of nicotine dependence by facilitating smoking cessation by decreasing nicotine intake and preventing relapse to smoking in humans.


Assuntos
Comportamento Aditivo , Moduladores GABAérgicos/uso terapêutico , Nicotina/farmacologia , Norbornanos/uso terapêutico , Pirimidinas/uso terapêutico , Receptores de GABA-B/metabolismo , Reforço Psicológico , Tabagismo/prevenção & controle , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Sinais (Psicologia) , Moduladores GABAérgicos/administração & dosagem , Moduladores GABAérgicos/farmacologia , Injeções Intravenosas , Masculino , Nicotina/administração & dosagem , Norbornanos/administração & dosagem , Norbornanos/farmacologia , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia , Ratos , Ratos Wistar , Recidiva , Autoadministração , Tabagismo/metabolismo , Tabagismo/psicologia
6.
Bioorg Med Chem Lett ; 20(20): 6103-7, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20813523

RESUMO

A novel series of trans-8-aminomethyl-1-oxa-3-azaspiro[4.5]decan-2-one derivatives was identified with potent NPY Y5 antagonist activity. Optimization of the original lead furnished compounds 23p and 23u, which combine sub-nanomolar Y5 activity with metabolic stability, oral bioavailability, brain penetration and strong preclinical profile for development. Both compounds significantly inhibited the food intake induced by a Y5 selective agonist with minimal effective doses of 3mg/kg po.


Assuntos
Carbamatos/química , Carbamatos/farmacologia , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Receptores de Neuropeptídeo Y/metabolismo , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Animais , Carbamatos/metabolismo , Carbamatos/farmacocinética , Linhagem Celular , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Microssomos Hepáticos/metabolismo , Ratos , Compostos de Espiro/metabolismo , Compostos de Espiro/farmacocinética , Relação Estrutura-Atividade
8.
Alcohol Clin Exp Res ; 33(10): 1749-56, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19572981

RESUMO

BACKGROUND: The positive allosteric modulators of the GABA(B) receptor, CGP7930 and GS39783, have been found to reduce alcohol self-administration in alcohol-preferring rats. The present study was designed to assess the effect of the newly synthesized positive allosteric modulator of the GABA(B) receptor, BHF177, on alcohol's reinforcing and motivational properties in selectively bred Sardinian alcohol-preferring (sP) rats. METHODS: sP rats were initially trained to respond on a lever [on a fixed ratio 4 (FR4) schedule of reinforcement] to orally self-administer alcohol (15%, v/v) or sucrose (1 to 3%, w/v) in daily 30-minute sessions. Once responding reached stable levels, rats were allocated to 2 different experiments: in the first experiment, rats were exposed to sessions with the FR4 schedule of reinforcement; in the second experiment, rats were exposed to sessions with a conventional progressive ratio (PR) schedule of reinforcement. In both experiments, the effect of BHF177 (0, 12.5, 25, and 50 mg/kg; i.g.) on responding for alcohol and sucrose (FR experiment: 1%, w/v; PR experiment: 3%, w/v) was determined. RESULTS: In the FR experiment, pretreatment with 25 and 50 mg/kg BHF177 produced a 30 and 45% reduction, respectively, in responding for alcohol. In the PR experiment, pretreatment with 50 mg/kg BHF177 resulted in a 35% reduction in breakpoint for alcohol (defined as the lowest response requirement not achieved by each rat and used as index of the motivational strength of alcohol). In both experiments, the effect of BHF177 on alcohol self-administration was specific, since responding for sucrose was unaltered by BHF177 pretreatment. CONCLUSIONS: The present results extend to BHF177 the capacity of the 2 previously tested positive allosteric modulators of the GABA(B) receptor, CGP7930 and GS39783, to specifically suppress alcohol's reinforcing and motivational properties in alcohol-preferring rats.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Consumo de Bebidas Alcoólicas/psicologia , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Moduladores GABAérgicos/farmacologia , Pirimidinas/farmacologia , Receptores de GABA-B/efeitos dos fármacos , Animais , Condicionamento Operante/efeitos dos fármacos , Interpretação Estatística de Dados , Relação Dose-Resposta a Droga , Masculino , Motivação , Ratos , Esquema de Reforço , Reforço Psicológico , Autoadministração
9.
J Pharmacol Exp Ther ; 326(1): 306-14, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18445779

RESUMO

Acute administration of gamma-aminobutyric acid (GABA)-B receptor agonists decreases nicotine, cocaine, ethanol, and heroin self-administration and also decreases food-maintained responding and suppresses locomotor activity at high doses. GABA(B) receptor-positive modulators may represent potentially improved therapeutic compounds because of their fewer side effects than receptor agonists. The present study investigated the effects of administration of the GABA(B) receptor-positive modulators 2,6-di-tert-butyl-4-(3-hydroxy-2,2-dimethyl-propyl)-phenol (CGP7930) and N-[(1R,2R,4S)-bicyclo[2.2.1]hept-2-yl]-2-methyl-5-[4-(trifluoromethyl)phenyl]-4-pyrimidinamine (BHF177) and coadministration of the GABA(B) receptor-positive modulator N,N'-dicyclopentyl-2-methylsulfanyl-5-nitro-pyrimidine-4,6-diamine (GS39783) with the GABA(B) receptor agonist (3-amino-2[S]-hydroxypropyl)-methylphosphinic acid (CGP44532) on nicotine- and food-maintained responding under fixed ratio (FR) 5 and progressive ratio schedules of reinforcement. Furthermore, the effects of BHF177 and CGP44532 on nicotine-induced enhancement of brain reward function were evaluated. The results indicated that administration of CGP7930 decreased nicotine self-administration under an FR5 schedule. Administration of either GS39783 or CGP44532 selectively decreased nicotine self-administration, whereas coadministration of these compounds had additive effects. BHF177 administration selectively decreased nicotine- but not food-maintained responding under FR5 and progressive ratio schedules. The nicotine-induced enhancement of brain reward function was blocked by BHF177 or CGP44532, although the highest doses of both compounds, particularly CGP44532, decreased brain reward function when administered alone, suggesting an additive, rather than interactive, effect. Overall, the present results indicate that GABA(B) receptor-positive modulators, similarly to GABA(B) receptor agonists, attenuated the reinforcing and reward-enhancing effects of nicotine, perhaps with higher selectivity than GABA(B) receptor agonists. Thus, GABA(B) receptor-positive modulators may be useful antismoking medications.


Assuntos
Encéfalo/efeitos dos fármacos , Agonistas dos Receptores de GABA-B , Nicotina/administração & dosagem , Recompensa , Animais , Encéfalo/fisiologia , Moduladores GABAérgicos/farmacologia , Masculino , Nicotina/antagonistas & inibidores , Ratos , Ratos Wistar , Receptores de GABA-B/fisiologia , Esquema de Reforço , Autoadministração
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