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1.
Encephale ; 2024 May 08.
Artigo em Francês | MEDLINE | ID: mdl-38724432

RESUMO

Psychiatric wards that only exceptionally use isolation and mechanical restraint may be suspected of using "chemical restraint". However, in the case of these services, the hypothesis of a reduction in the general level of restraint can also be formulated. Prior to a comprehensive study to test these hypotheses, the current research aims to assess indicators which define high levels of the use of these measures and a relevant sample. The study was conducted in three facilities with 254 hospitalized patients over a week. Five per cent experienced isolation, 2% mechanical restraint, and 13% received high doses of medication (including "as needed" treatments). These figures are below literature data and national averages. Variances exist among centers, with one showing higher percentages for all three measures. While confirming the feasibility of studying these measures together, the study suggests the need for longer observations and continuous evaluation of prescription practices to better reflect yearly isolation and restraint trends. Future studies should involve more centers and include case studies for a nuanced understanding of administration practices in relation to prescriptions.

3.
Encephale ; 49(4): 433-436, 2023 Aug.
Artigo em Francês | MEDLINE | ID: mdl-37127482

RESUMO

The use of coercion is a common practice in psychiatry despite its deleterious effects and insufficient evidence of benefits. It is so deeply rooted that the mention of establishments that make little use of it arouses a form of incredulity. However, the history of psychiatry and the international literature provide numerous examples of a psychiatry that is hardly coercive and numerous experiences of a reduction in the use of seclusion and/or restraint in psychiatric facilities. Today, in France, there are also less coercive establishments, which, for example, do not use mechanical restraint, have all their units open, or have reduced their use of seclusion and restraint. With regard to the stated policy objectives of reducing the use of coercion, it is surprising that most of these facilities receive little attention. PLAID-Care research aims to contribute to the visibility and analysis of these institutions and the factors involved in the reduced use of coercion. While these factors have already been identified in the international literature, the research is based on the multiplication of disciplinary perspectives (nursing, sociology, anthropology, geography) and the mobilization of a multi-level analytical framework that allows us to embrace their multiplicity and better understand their articulation. The originality of the research also lies in its historical dimension, which allows us to understand, on the scale of an institution, how a policy and practices aiming at the least recourse emerge and are consolidated. The project timeline is divided in three tasks: firstly, an inventory of "low-coercion" facilities in France; secondly, we will select and research four traditionally "low-coercion" facilities in France; thirdly we will focus on recently emerged "low-coercion" practices. PLAID-Care aims to revitalize French research on this theme which to date has been relatively lagging behind the numerous international studies. It will bring together and articulate the knowledge, tools and forms of organization and collaboration that contribute to making a policy of lesser use of coercion operational.


Assuntos
Coerção , Transtornos Mentais , Humanos , Hospitais Psiquiátricos , Isolamento de Pacientes , França , Restrição Física
4.
Sante Publique ; 34(5): 613-619, 2022.
Artigo em Francês | MEDLINE | ID: mdl-36577660

RESUMO

AIM: Considering the persistent excess mortality of people living with a mental disorder, this article provides an overview of potential causes to identify relevant research perspectives and to support the development of short-term measures in the French context. METHODS: We rely on a narrative review of the literature, both quantitative and qualitative, to define a conceptual framework of the different factors which could contribute to this excess mortality. Particular attention is given to research carried out in France to identify possible measures to implement in line with the specificities of the national context. RESULTS: The excess mortality of people living with a mental disorder represents a health inequality resulting from a combination of factors, which are not only linked to individual behaviors and living conditions detrimental to health but also to the health system – both in terms of its organization and of the health professionals involved. Questions relating to the extent of the role played by the different factors and to the way they interact (specific social processes, combination of inequalities or a particular convergence at the crossing of all these factors…) remain. CONCLUSION: These findings support the development of complementary research, relying on mixed methodologies, as well as of measures promoting access to somatic care for people living with a mental disorder throughout their care pathways (stronger development of prevention and patient education, better integration of somatic and psychiatric care teams, alternative modes of funding supporting a holistic approach to health…).


Objectif: Face au constat d'une surmortalité persistante des personnes vivant avec un trouble psychique, cet article dresse un état des lieux de ses causes potentielles afin d'identifier des perspectives de recherche et d'étayer la mise en place d'actions à court terme dans le contexte français. Méthodes: Nous nous appuyons sur une revue narrative de la littérature, quantitative et qualitative, mobilisée pour proposer un cadre conceptuel des différents facteurs pouvant jouer un rôle dans cette surmortalité. Une attention particulière est portée aux recherches françaises afin d'identifier des pistes d'actions adaptées aux spécificités de ce contexte national. Résultats: La surmortalité des personnes vivant avec un trouble psychique constitue une inégalité de santé résultant d'une combinaison de facteurs qui ne sont pas uniquement liés à des comportements individuels et des conditions de vie défavorables à la santé, mais également au système de santé ­ tant du point de vue de son organisation que des professionnels y intervenant. Des interrogations, relatives à l'ampleur du rôle joué par les différents facteurs et à la façon dont ils interagissent (traitement social spécifique, cumul d'inégalités ou conjonction singulière au croisement de ces facteurs…), demeurent. Conclusions: Ces résultats appellent la mise en œuvre de recherches complémentaires, mobilisant des schémas d'études mixtes, ainsi que de mesures favorisant l'accès aux soins somatiques des personnes vivant avec un trouble psychique, tout au long des parcours de soins (prévention, éducation thérapeutique, meilleure intégration des services somatiques et psychiatriques, modes de financement des soins encourageant une prise en charge globale de la santé…).


Assuntos
Disparidades nos Níveis de Saúde , Transtornos Mentais , Humanos , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , França/epidemiologia , Pessoal de Saúde
5.
Front Plant Sci ; 13: 809056, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444680

RESUMO

Pea or Pisum sativum L. is a key diversification crop, but current varieties are not very competitive against weeds. The objective was to identify, depending on the type of cropping system and weed flora, (1) the key pea parameters that drive crop production, weed control and weed contribution to biodiversity, (2) optimal combinations of pea-parameter values and crop-management techniques to maximize these goals. For this, virtual experiments were run, using FLORSYS, a mechanistic simulation model. This individual-based 3D model simulates daily crop-weed seed and plant dynamics over the years, from the cropping system and pedoclimate. Here, this model was parameterized for seven pea varieties, from experiments and literature. Moreover, ten virtual varieties were created by randomly combining variety-parameter values according to a Latin Hypercube Sampling (LHS) plan, respecting parameter ranges and correlations observed in the actual varieties. A global sensitivity analysis was run, using another LHS plan to combine pea varieties, crop rotations and management techniques in nine contrasting situations (e.g., conventional vs. organic, no-till, type of weed flora). Simulated data were analyzed with classification and regression trees (CART). We highlighted (1) Parameters that drive potential yield and competitivity against weeds (notably the ability to increase plant height and leaf area in shaded situations), depending on variety type (spring vs. winter) and cropping system. These are pointers for breeding varieties to regulate weeds by biological interactions; (2) Rules to guide farmers to choose the best pea variety, depending on the production goal and the cropping system; (3) The trade-off between increasing yield potential and minimizing yield losses due to weeds when choosing pea variety and management, especially in winter peas. The main pea-variety rules were the same for all performance goals, management strategies, and analyses scales, but further rules were useful for individual goals, strategies, and scales. Some variety features only fitted to particular systems (e.g., delayed pea emergence is only beneficial in case of herbicide-spraying and disastrous in unsprayed systems). Fewer variety rules should be compensated by more management rules. If one of the two main weed-control levers, herbicide or tillage, was eliminated, further pea-variety and/or management rules were needed.

6.
Data Brief ; 31: 105890, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32613047

RESUMO

The data presented in this article describe 21 species that can be found in banana cropping systems: 17 cover crops species, 2 spontaneous species and 2 cultivars of banana. The cover crop species belongs mainly to Fabaceae family, but also to Poaceae, Euphorbiacea and Asteraceae. Four repetition of each species were cultivated individually, in the field, under non-limiting conditions. 40 variables were measured on whole plant, leaves and roots, at flowering or after six months of growth for longer cycle species. This dataset is made available to provide data on these species, enable comparisons between datasets and meta-analysis on cover crop or on species presented in arable fields. The data presented in this article were used in the research articles entitled "Trait-based characterisation of cover plants' light competition strategies for weed control in banana cropping systems in the French West Indies" (Tardy et al. 2015) and "Trait-based characterization of soil exploitation strategies of banana, weeds and cover plant species" (Tardy et al. 2017).

7.
Arch Suicide Res ; 24(sup2): S150-S164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30856364

RESUMO

The objective of this study was to identify health care-related factors associated with death by suicide in psychiatric patients and to gain insight into clinician views on how to deal with suicidality. The study material derived from a clinician committee in a psychiatric department reviewing every outpatient and inpatient suicide in a standardized way. Reports' conclusions and corresponding plenary discussion minutes regarding 94 suicides were analyzed using inductive thematic content analysis. Health care-related factors were categorized into 4 themes: patient evaluation, patient management, clinician training, and involvement of relevant non-clinical partners. Clinician views on the themes were expressed through statements (i) promoting or restricting an aspect of care (here called recommendations), which mainly followed existing guidelines and were consensual and (ii) without precise indication (here called comments), which departed from mainstream opinions or addressed topics not covered by existing policy. Involvement of non-clinical partners emerged as a new key issue for suicide prevention in psychiatric departments and should be openly discussed with patients. Clinicians preferred balanced conclusions when they reviewed suicide cases.


Assuntos
Prevenção do Suicídio , Atenção à Saúde , Humanos , Pacientes Internados
8.
Health Res Policy Syst ; 16(1): 34, 2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29673362

RESUMO

BACKGROUND: In 2006, a local collective combating homelessness set up an 'experimental squat' in an abandoned building in Marseille, France's second largest city. They envisioned the squat as an alternative to conventional health and social services for individuals experiencing long-term homelessness and severe psychiatric disorders. Building on what they learned from the squat, some then joined a larger coalition that succeeded in convincing national government decision-makers to develop a scientific, intervention-based programme based on the Housing First model. This article analyses the political process through which social movement activism gave way to support for a state-funded programme for homeless people with mental disorders. METHODS: A qualitative study of this political process was conducted between 2006 and 2014, using a hybrid theoretical perspective that combines attention to both top-down and bottom-up actions with a modified Advocacy Coalition Framework. In addition to document analysis of published and grey literature linked to the policy process, researchers drew on participant observation and observant participation of the political process. Data analysis consisted primarily of a thematic analysis of field-notes and semi-structured interviews with 65 relevant actors. RESULTS: A coalition of local activists, state officials and national service providers transformed knowledge about a local innovation (an experimental therapeutic squat) into the rationale for a national, scientifically based project consisting of a randomised controlled trial of four state-supported Housing First sites, costing several million euros. The coalition's strategy was two-pronged, namely to defend a social cause (the right to housing) and to promote a scientifically validated means of realising positive outcomes (housing tenure) and cost-effectiveness (reduced hospitalisation costs). CONCLUSION: Activists' self-agency, especially that of making themselves audible to public authorities, was enhanced by the coalition's ability to seize 'windows of opportunities' to their advantage. However, in contrast to the United States and Canadian Housing First contexts, which are driven by implementation science and related approaches, it was grassroots activists who promoted a scientific-technical approach among government officials unfamiliar with evidence-based practices in France. The windows of opportunity nevertheless failed to attract participation of those most in need of housing, raising the question of whether and how marginalised and/or subordinate groups can be integrated into collaborative research when a social movement-driven innovation turns into a scientific approach. TRIAL REGISTRATION: The current clinical trial number is NCT01570712 . Registered July 17, 2011. First patient enrolled August 18, 2011.


Assuntos
Pesquisa Participativa Baseada na Comunidade , Prática Clínica Baseada em Evidências , Financiamento Governamental , Habitação , Pessoas Mal Alojadas , Ativismo Político , Projetos de Pesquisa , Canadá , Participação da Comunidade , Comportamento Cooperativo , Análise Custo-Benefício , França , Programas Governamentais , Direitos Humanos , Humanos , Transtornos Mentais , Resolução de Problemas , Pesquisa Qualitativa , Estados Unidos
9.
Artigo em Inglês | MEDLINE | ID: mdl-29538346

RESUMO

This paper is a qualitative analysis of the effects of accompagnement, a support framework, on recovery trajectories of people with long-term homelessness and severe psychiatric disorders during 24 months in a Housing First-type program in France. A comprehensive methodology based on grounded theory was used to construct an interview guide, conduct multiple interviews with 35 Housing First participants sampled for heterogeneity, and produce memos on their trajectories before and after entering the program based on interview information. Thematic analysis of a representative subsample (n = 13) of memos identified 12 objective factors and 6 subjective factors key to the recovery process. An in-depth re-analysis of the memos generated four recovery themes: (1) the need for secure space favorable to self-reflexivity; (2) a "honeymoon" effect; (3) the importance of even weak social ties; (4) support from and hope among peers. Three challenges to recovery were identified: (1) finding a balance between protection and risk; (2) breaking downward spirals; (3) bifurcating the trajectory. This study provides new insight into the recovery process, understood as a non-linear transformation of an experience-the relationship between objective life conditions and subjective perception of those conditions-which reinforces protective support over risk elements.


Assuntos
Habitação/estatística & dados numéricos , Pessoas Mal Alojadas/estatística & dados numéricos , Transtornos Mentais/epidemiologia , França/epidemiologia , Teoria Fundamentada , Pessoas Mal Alojadas/psicologia , Humanos , Entrevistas como Assunto , Transtornos Mentais/psicologia , Grupo Associado , Pesquisa Qualitativa , Apoio Social
10.
PLoS One ; 12(3): e0173066, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28257454

RESUMO

Cover plants can be introduced in cropping systems to provide agroecosystem services, including weed control via competition for resources. There is currently no consensus on how to identify the best cover plant species, while trait-based approaches are promising for screening plant species due to their agroecosystem service provision potential. This study was carried out to characterize soil exploitation strategies of cover plant species in banana agroecosystems using a trait-based approach, and in turn identify cover plant species with a high weed control potential via competition for soil resources in banana cropping systems. A field experiment was conducted on 17 cover plant species, two weed species and two banana cultivars grown individually. Four functional traits were measured. Two of them (i.e., the size of the zone explored by roots and the root impact density) were used to characterize root system soil exploration patterns. Two other traits (i.e., specific root length and root diameter) were used to characterize resource acquisition within the soil zone explored by the roots. All studied traits exhibited marked variations among species. The findings suggested a trade-off between the abilities of species to develop a limited number of large diameter roots exploring a large soil zone versus many thin roots exploring a smaller soil zone. Three soil-resource exploitation strategies were identified among species: (i) with large diameter roots that explore a large soil zone; (ii) with small diameter roots and a high specific length that explore a smaller soil zone; and (iii) with a high total root-impact density and an intermediate specific root length that explore the uppermost soil layers. Interestingly, in our panel of species, no correlations with regard to belowground and aboveground strategies were noted: species with an acquisitive belowground strategy could display an acquisitive or a conservative aboveground strategy. The findings of this study illustrated that a trait-based approach could be used to identify plant species with potential for competing with weeds, while minimising competition with banana. Six of the 17 studied cover crop species were identified as having this potential. The next step will be to assess them for their weed control performances in banana cropping systems with low reliance on herbicides.


Assuntos
Fabaceae/fisiologia , Musa/fisiologia , Raízes de Plantas/fisiologia , Poaceae/fisiologia , Plantas Daninhas/crescimento & desenvolvimento , Plantas Daninhas/parasitologia , Característica Quantitativa Herdável , Solo/química , Controle de Plantas Daninhas/métodos
11.
Front Plant Sci ; 7: 1033, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27468293

RESUMO

Phelipanche ramosa (L.) Pomel (branched broomrape) is a holoparasitic plant that reproduces on crops and also on weeds, which contributes to increase the parasite seed bank in fields. This parasite extracts all its nutrients at the host's expense so that host-parasite trophic relationships are crucial to determine host and parasite growth. This study quantified the intensity with which P. ramosa draws assimilates from its host and analyzed whether it varied with host species, host phenological stage and host growth rate. A greenhouse experiment was conducted on three host species: the crop species Brassica napus (L.) (oilseed rape) and two weed species, Capsella bursa-pastoris (L.) Medik. and Geranium dissectum (L.). Plants were grown with or without P. ramosa and under three light levels to modulate host growth rate. The proportion of host biomass loss due to parasitism by P. ramosa differed between host species (at host fructification, biomass loss ranged from 34 to 84%). B. napus and C. bursa-pastoris displayed a similar response to P. ramosa, probably because they belong to the same botanical family. The sensitivity to P. ramosa in each host species could be related to the precocity of P. ramosa development on them. Host compartments could be ranked as a function of their sensitivity to parasitism, with the reproductive compartment being the most severely affected, followed by stems and roots. The proportion of biomass allocated to leaves was not reduced by parasitism. The proportion of pathosystem biomass allocated to the parasite depended on host species. It generally increased with host stage progression but was constant across light induced-host growth rate, showing that P. ramosa adapts its growth to host biomass production. The rank order of host species in terms of sink strength differed from that in terms of host sensitivity. Finally, for B. napus, the biomass of individual parasite shoots decreased with increasing their number per host plant, regardless of host growth rate. Results will be incorporated into a mechanistic model in order to analyze the effect of parasitic plant species on weed community assembly and to design new cropping systems for controlling P. ramosa.

12.
Plant Methods ; 12: 31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27279895

RESUMO

BACKGROUND: In order to maintain high yields while saving water and preserving non-renewable resources and thus limiting the use of chemical fertilizer, it is crucial to select plants with more efficient root systems. This could be achieved through an optimization of both root architecture and root uptake ability and/or through the improvement of positive plant interactions with microorganisms in the rhizosphere. The development of devices suitable for high-throughput phenotyping of root structures remains a major bottleneck. RESULTS: Rhizotrons suitable for plant growth in controlled conditions and non-invasive image acquisition of plant shoot and root systems (RhizoTubes) are described. These RhizoTubes allow growing one to six plants simultaneously, having a maximum height of 1.1 m, up to 8 weeks, depending on plant species. Both shoot and root compartment can be imaged automatically and non-destructively throughout the experiment thanks to an imaging cabin (RhizoCab). RhizoCab contains robots and imaging equipment for obtaining high-resolution pictures of plant roots. Using this versatile experimental setup, we illustrate how some morphometric root traits can be determined for various species including model (Medicago truncatula), crops (Pisum sativum, Brassica napus, Vitis vinifera, Triticum aestivum) and weed (Vulpia myuros) species grown under non-limiting conditions or submitted to various abiotic and biotic constraints. The measurement of the root phenotypic traits using this system was compared to that obtained using "classic" growth conditions in pots. CONCLUSIONS: This integrated system, to include 1200 Rhizotubes, will allow high-throughput phenotyping of plant shoots and roots under various abiotic and biotic environmental conditions. Our system allows an easy visualization or extraction of roots and measurement of root traits for high-throughput or kinetic analyses. The utility of this system for studying root system architecture will greatly facilitate the identification of genetic and environmental determinants of key root traits involved in crop responses to stresses, including interactions with soil microorganisms.

13.
Ecology ; 96(8): 2300-10, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26405754

RESUMO

Plant species are important drivers of soil microbial communities. However, how plant functional traits are shaping these communities has received less attention though linking plant and microbial traits is crucial for better understanding plant-microbe interactions. Our objective was to determine how plant-microbe interactions were affected by plant traits. Specifically we analyzed how interactions between plant species and microbes involved in nitrogen cycling were affected by plant traits related to 'nitrogen nutrition in interaction with soil nitrogen availability. Eleven plant species, selected along an oligotrophic-nitrophilic gradient, were grown individually in a nitrogen-poor soil with two levels of nitrate availability. Plant traits for both carbon and nitrogen nutrition were measured and the genetic structure and abundance of rhizosphere. microbial communities, in particular the ammonia oxidizer and nitrate reducer guilds, were analyzed. The structure of the bacterial community in the rhizosphere differed significantly between plant species and these differences depended on nitrogen availability. The results suggest that the rate of nitrogen uptake per unit of root biomass and per day is a key plant trait, explaining why the effect of nitrogen availability on the structure of the bacterial community depends on the plant species. We also showed that the abundance of nitrate reducing bacteria always decreased with increasing nitrogen uptake per unit of root biomass per day, indicating that there was competition for nitrate between plants and nitrate reducing bacteria. This study demonstrates that nitrate-reducing microorganisms may be adversely affected by plants with a high nitrogen uptake rate. Our work puts forward the role of traits related to nitrogen in plant-microbe interactions, whereas carbon is commonly considered as the main driver. It also suggests that plant traits related to ecophysiological processes, such as nitrogen uptake rates, are more relevant for understanding plant-microbe interactions than composite traits, such as nitrophily, which are related to a number of ecophysiological processes.


Assuntos
Nitrogênio/metabolismo , Plantas/metabolismo , Rizosfera , Microbiologia do Solo , Bactérias/genética , Crenarchaeota/genética , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Solo/química
14.
Plant Physiol ; 160(3): 1479-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22984122

RESUMO

Vertical leaf nitrogen (N) gradient within a canopy is classically considered as a key adaptation to the local light environment that would tend to maximize canopy photosynthesis. We studied the vertical leaf N gradient with respect to the light gradient for wheat (Triticum aestivum) canopies with the aims of quantifying its modulation by crop N status and genetic variability and analyzing its ecophysiological determinants. The vertical distribution of leaf N and light was analyzed at anthesis for 16 cultivars grown in the field in two consecutive seasons under two levels of N. The N extinction coefficient with respect to light (b) varied with N supply and cultivar. Interestingly, a scaling relationship was observed between b and the size of the canopy for all the cultivars in the different environmental conditions. The scaling coefficient of the b-green area index relationship differed among cultivars, suggesting that cultivars could be more or less adapted to low-productivity environments. We conclude that the acclimation of the leaf N gradient to the light gradient is a whole-plant process that depends on canopy size. This study demonstrates that modeling leaf N distribution and canopy expansion based on the assumption that leaf N distribution parallels that of the light is inappropriate. We provide a robust relationship accounting for vertical leaf N gradient with respect to vertical light gradient as a function of canopy size.


Assuntos
Aclimatação/fisiologia , Luz , Nitrogênio/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Triticum/crescimento & desenvolvimento , Triticum/efeitos da radiação , Aclimatação/efeitos da radiação , Produtos Agrícolas/metabolismo , Produtos Agrícolas/efeitos da radiação , Modelos Lineares , Tamanho do Órgão/efeitos da radiação , Fótons , Fotossíntese/efeitos da radiação , Folhas de Planta/efeitos da radiação
15.
Plant Signal Behav ; 7(3): 311-3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22499204

RESUMO

One difficulty when analyzing the determinants at the origin of plant phenotypic differences is that measured plant traits are frequently integrative: they result from the integration of a large number of physiological processes under the control of genetic and environmental factors. In a previous report, we demonstrated that dissecting integrative traits into simpler components using a simple crop physiology model was a valuable method for detecting quantitative trait loci (QTL) related to the nitrogen nutrition for a recombinant inbred lines population of Medicago truncatula. Here, using the same data set, we demonstrate the relevance of decomposing integrative traits for understanding biological differences among phenotypes, independently of QTL detection. Two examples are given to demonstrate that the dissection of integrative traits (i.e., plant leaf area and nitrogen nutrition index) into variables representing the efficiency of the plant to extract and valorize (carbon and nitrogen) resources is an effective method to determine the stream of physiological events that leads to the final phenotype.


Assuntos
Plantas/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Plantas/genética , Locos de Características Quantitativas/genética
16.
Theor Appl Genet ; 124(4): 755-68, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22113590

RESUMO

Medicago truncatula is used as a model plant for exploring the genetic and molecular determinants of nitrogen (N) nutrition in legumes. In this study, our aim was to detect quantitative trait loci (QTL) controlling plant N nutrition using a simple framework of carbon/N plant functioning stemming from crop physiology. This framework was based on efficiency variables which delineated the plant's efficiency to take up and process carbon and N resources. A recombinant inbred line population (LR4) was grown in a glasshouse experiment under two contrasting nitrate concentrations. At low nitrate, symbiotic N(2) fixation was the main N source for plant growth and a QTL with a large effect located on linkage group (LG) 8 affected all the traits. Significantly, efficiency variables were necessary both to precisely localize a second QTL on LG5 and to detect a third QTL involved in epistatic interactions on LG2. At high nitrate, nitrate assimilation was the main N source and a larger number of QTL with weaker effects were identified compared to low nitrate. Only two QTL were common to both nitrate treatments: a QTL of belowground biomass located at the bottom of LG3 and another one on LG6 related to three different variables (leaf area, specific N uptake and aboveground:belowground biomass ratio). Possible functions of several candidate genes underlying QTL of efficiency variables could be proposed. Altogether, our results provided new insights into the genetic control of N nutrition in M. truncatula. For instance, a novel result for M. truncatula was identification of two epistatic interactions in controlling plant N(2) fixation. As such this study showed the value of a simple conceptual framework based on efficiency variables for studying genetic determinants of complex traits and particularly epistatic interactions.


Assuntos
Medicago truncatula/genética , Nitrogênio/metabolismo , Folhas de Planta/genética , Locos de Características Quantitativas , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Genes de Plantas , Ligação Genética , Medicago truncatula/crescimento & desenvolvimento , Fenótipo
17.
Psicol. rev. (Belo Horizonte) ; 15(3): 1-21, dez. 2009.
Artigo em Português | LILACS | ID: lil-603478

RESUMO

As hospitalizações sem consentimento estão no centro da acusação contra a Psiquiatria, por esta exercer coerções ilegítimas. Essa crítica é feita pelos próprios profissionais da área. Com cerca de 13 por cento de hospitalizações em duas modalidades definidas pela Lei 90-527, de 27/06/1990 - a hospitalização de ofício e aquela resultante da demanda de um terceiro -, o exercício da coerção é parte integrante do tratamento psiquiátrico e pode incluir reclusão em quartos de isolamento, tratamentos e outras coerções relativas às condições de hospitalização (vestimentas, visitas, recomendações, etc.). A partir de entrevistas com diferentes categorias de profissionais (médicos, enfermeiros e técnicos) e de observações etnográficas nos serviços de urgência psiquiátrica e num serviço de hospitalização, analisamos, por meio de uma abordagem compreensiva, a maneira pela qual os profissionais justificam o uso da coerção e definem seus limites, de maneira a afastar a qualificação de violência.


Les hospitalisations sans consentement n’ont cessé d’être au coeur de l’accusation portée contre la psychiatrie d’exercer des contraintes illégitimes, critique menée parfois par les professionnels eux-mêmes. Avec près de 13 percent des hospitalisations réalisées sous l’une des deux modalités définies par la loi du 27 juin 1990, l’hospitalisation d’office et à la demande d’un tiers, l’exercice de la contrainte est partie prenante du soin psychiatrique, et peut inclure placement en chambre d’isolement, administration de traitements, et autres contraintes concernant les conditions de l’hospitalisation (vêtements, visites, appels, etc.). A partir d’entretiens avec les différentes catégories de soignants (médecins, infirmiers et aides-soignants) et d’observations ethnographiques menées dans des services d’urgence psychiatrique et dans un service d’hospitalisation, nous avons analysé dans une approche compréhensive la manière dont les professionnels justifient le recours à la contrainte et en définissent les limites de façon à écarter la qualification de violence.


Hospitalization without consent is in the core of accusations against Psychiatry as it exerts illegitimate coercions, a criticism often expressed by professionals in the area themselves. With around 13 percent of the hospitalizations carried out in two modes defined by the Law dated June 27, 1990 - office hospitalization and that resulting from a third party’s demand - the exercise of coercion is an integral part of psychiatric treatment and may include reclusion in isolation rooms, administration of treatments and other coercions related to hospitalization conditions (clothing, visits, recommendations, etc.). Based on interviews with various categories of professionals (doctors, nurses and technicians), as well as on ethnographic observations in psychiatric urgency services and in one hospitalization service, we analyzed, by means of a comprehensive approach, the way professionals justify the use of coercion and define its limits, so as to evade the qualification of violence.


Las hospitalizaciones sin consentimiento están en el centro de las acusaciones contra la Psiquiatría, ya que esta ejerce coacciones ilegítimas, crítica que a veces hacen los propios profesionales del área. Cerca del 13 por ciento de las hospitalizaciones se realizan en dos modalidades definidas por la ley de 27 de junio de 1990 - la hospitalización de oficio y la que resulta de la demanda de un tercero -, el ejercicio de la coacción forma parte del tratamiento y puede incluir la reclusión en cuartos de aislamiento, administración de tratamientos y otras coacciones relativas a las condiciones de hospitalización (vestiduras, visitas, recomendaciones, etc.). Basándonos en entrevistas a diferentes categorías de profesionales (médicos, enfermeros y técnicos) y de observaciones etnográficas en los servicios de urgencia psiquiátrica y en un servicio de hospitalización, analizamos, a través de un abordaje comprensivo, como los profesionales justifican el uso de la coacción y definen sus límites para que no llegue a ser clasificada como una violencia.


Assuntos
Hospitais Psiquiátricos , Violência , Coerção
18.
C R Biol ; 332(11): 1022-33, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19909924

RESUMO

An integrative biology approach was conducted in Medicago truncatula for: (i) unraveling the coordinated regulation of NO3-, NH4+ and N(2) acquisition by legumes to fulfill the plant N demand; and (ii) modeling the emerging properties occurring at the whole plant level. Upon localized addition of a high level of mineral N, the three N acquisition pathways displayed similar systemic feedback repression to adjust N acquisition capacities to the plant N status. Genes associated to these responses were in contrast rather specific to the N source. Following an N deficit, NO3- fed plants maintained efficiently their N status through rapid functional and developmental up regulations while N(2) fed plants responded by long term plasticity of nodule development. Regulatory genes associated with various symbiotic stages were further identified. An ecophysiological model simulating relations between leaf area and roots N retrieval was developed and now furnishes an analysis grid to characterize a spontaneous or induced genetic variability for plant N nutrition.


Assuntos
Medicago truncatula/efeitos dos fármacos , Modelos Biológicos , Nitratos/farmacologia , Fixação de Nitrogênio/fisiologia , Nitrogênio/metabolismo , Compostos de Amônio Quaternário/farmacologia , Adaptação Fisiológica , Retroalimentação Fisiológica , Fertilizantes , Genes de Plantas , Genes Reguladores , Medicago truncatula/genética , Medicago truncatula/metabolismo , Medicago truncatula/microbiologia , Nitratos/metabolismo , Fixação de Nitrogênio/genética , Folhas de Planta/metabolismo , Nodulação/genética , Nodulação/fisiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/metabolismo , Compostos de Amônio Quaternário/metabolismo , Nódulos Radiculares de Plantas/crescimento & desenvolvimento , Nódulos Radiculares de Plantas/microbiologia , Sinorhizobium meliloti/fisiologia , Simbiose , Integração de Sistemas
19.
Plant Signal Behav ; 4(1): 30-2, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19704700

RESUMO

The international consensus on Medicago truncatula as a model system has lead to the development of powerful approaches for dissecting the genetic and molecular bases of legume nitrogen nutrition. However, such approaches now come up against a poor knowledge of the phenotypic traits that should be used for the large-scale screening of the genotypic variability associated with nitrogen nutrition. This issue was unravelled in a previous report, in which an ecophysiological approach allowed a better understanding of the relationships between plant nitrogen nutrition and plant growth traits, for the model symbiotic association between M. truncatula cv. Jemalong and Rhizobium meliloti strain 2011. From this analysis, phenotypic traits were identified as potentially relevant for the large-scale screening of the genotypic variability. Here, by the phenotyping of a recombinant inbred lines population, we show that the proposed methodology provides a valuable support for assisting the detection of genetic variants affected for nitrogen uptake. Especially, the relative expansion rate of plant leaf area is identified as a good proxy for ranking genotypes according to their ability to uptake nitrogen in given environmental conditions. As leaf area can be measured non-destructively, such finding should pave the way for a more efficient evaluation of the genotypic variability.

20.
J Exp Bot ; 59(13): 3509-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18703494

RESUMO

A better knowledge of the nitrogen nutrition of Medicago truncatula at the whole plant level and its modulation by environmental factors is a crucial step to reach a complete understanding of legume nitrogen nutrition. This study was based on the symbiotic system that is the most commonly used by the research community (M. truncatula cv. Jemalong A17 x Rhizobium meliloti strain 2011). Plant nitrogen nutrition was analysed in relation to carbon nutrition, under a range of nitrate concentrations in the nutrient solution and different light conditions. This study shows that this 'model symbiotic association' does not allow the plant to meet its nitrogen requirements, when dinitrogen fixation is the main nitrogen source for plant growth. A strong interaction between nitrogen and carbon nutrition was shown: when plant nitrogen requirements were not sustained, plant leaf area was much affected whereas photosynthesis per unit leaf area remained relatively stable. Both total nitrogen uptake and leaf area increased with increasing nitrate concentration in the nutrient solution; the magnitude of these responses varied according to the light conditions. Interestingly, the plant nitrogen nutrition level remained nearly unaffected by the light conditions. The observed nitrogen-limitation in this 'model symbiotic association' is an important finding for the research community. Based on practical recommendations regarding both the experimental conditions and the phenotypic traits to consider, a methodological framework was proposed to (i) help genomicists to assess plant nitrogen nutrition better, and (ii) assist in the detection of new genetic variants affected for nitrogen uptake in large-scale phenotyping studies.


Assuntos
Medicago truncatula/fisiologia , Modelos Biológicos , Fixação de Nitrogênio , Nitrogênio/metabolismo , Sinorhizobium meliloti/fisiologia , Simbiose , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/efeitos da radiação , Nitratos/metabolismo , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação
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