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1.
Catheter Cardiovasc Interv ; 101(1): 60-71, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36378683

RESUMO

BACKGROUND: The polymer-free biolimus coated stent (BioFreedom) was shown to be superior to bare metal stents in the LEADERS FREE randomized trial in high bleeding risk (HBR) patients treated with 1-month dual antiplatelet therapy (DAPT). However, there is limited outcome data with this device in an all-comers' population. METHODS: We conducted a prospective single-arm study of patients undergoing percutaneous coronary intervention with the polymer-free biolimus coated stent in 25 centers in France with wide inclusion criteria including multivessel disease, complex lesions, and acute coronary syndromes. The primary endpoint was the incidence of target lesion failure (TLF), a composite of cardiac death or target-vessel myocardial infarction (MI) or clinically indicated target lesion revascularization (ci-TLR) at 1-year. The patient population was classified according to the presence (or not) of HBR criteria according to the recent ARC-HBR definition. RESULTS: Between April 2019 and April 2020, 1497 patients were enrolled. TLF occurred in 101 (6.9%) patients, including cardiac death in 35 (2.4%), target vessel MI in 20 (1.4%) and ci-TLR in 65 (4.5%) of them. There were 491 HBR patients (32.8%) and 1006 non-HBR patients. The median duration of DAPT was 74 days in the HBR group versus 348 days in the non-HBR group (p < 0.0001). TLF occurred in 44 (9.2%) of the HBR group and in 57 (5.8%) of the non-HBR group (relative risk 1.62 [95% confidence interval: 1.10-2.41], p = 0015). Compared to the non-HBR group, HBR patients had higher rates of cardiac death (4.4% vs. 1.4%, p = 0.0005) and target vessel MI (2.9% vs. 0.6%, p = 0.0003), but similar rates of ci-TLR. BARC 3-5 bleeding occurred in 6.2% of the HBR group versus 1.4% of the non-HBR group (p < 0.0001). CONCLUSION: In this multicenter all-comers study, HBR patients treated with a polymer-free biolimus coated stent had, compared to non-HBR patients, an increased risk of cardiac death and MI, and despite a shorter duration of DAPT, continued to have higher rates of BARC 3-5 bleeding.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/complicações , Inibidores da Agregação Plaquetária/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Polímeros , Estudos Prospectivos , Stents Farmacológicos/efeitos adversos , Sirolimo/efeitos adversos , Desenho de Prótese , Resultado do Tratamento , Stents/efeitos adversos , Infarto do Miocárdio/etiologia , Hemorragia/induzido quimicamente , França , Morte
2.
Molecules ; 28(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36838541

RESUMO

Resistance to conventional treatments renders urgent the discovery of new therapeutic molecules. Plant specialized metabolites such as phenolamides, a subclass of phenolic compounds, whose accumulation in tomato plants is mediated by the biotic and abiotic environment, constitute a source of natural molecules endowed with potential antioxidant, antimicrobial as well as anti-inflammatory properties. The aim of our study was to investigate whether three major phenolamides found in Tuta absoluta-infested tomato leaves exhibit antimicrobial, cytotoxic and/or anti-inflammatory properties. One of them, N1,N5,N14-tris(dihydrocaffeoyl)spermine, was specifically synthesized for this study. The three phenolamides showed low to moderate antibacterial activities but were able to counteract the LPS pro-inflammatory effect on THP-1 cells differentiated into macrophages. Extracts made from healthy but not T. absoluta-infested tomato leaf extracts were also able to reduce inflammation using the same cellular approach. Taken together, these results show that phenolamides from tomato leaves could be interesting alternatives to conventional drugs.


Assuntos
Lepidópteros , Mariposas , Solanum lycopersicum , Animais
3.
Ann Vasc Surg ; 79: 443.e1-443.e3, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34656715

RESUMO

Abdominal trauma leads rarely to severe renal injury such as acquired arterioveinous fistula. Here, we present the case of a 46-year-old man with a history of suicide attempt by a gunshot in the abdomen. At that time, explorative laparotomy was unremarkable. He consulted 23 years later for chronic left lumbar pain and was diagnosed with an arterioveinous fistula of left renal vessels with a-10-cm aneurysm of the left renal artery. We performed a left nephrectomy and endovascular clamping was the best option to manage this giant aneurysm in a hostile abdomen.


Assuntos
Traumatismos Abdominais/etiologia , Aneurisma/etiologia , Fístula Arteriovenosa/etiologia , Artéria Renal/lesões , Veias Renais/lesões , Lesões do Sistema Vascular/etiologia , Ferimentos por Arma de Fogo/complicações , Traumatismos Abdominais/diagnóstico por imagem , Traumatismos Abdominais/cirurgia , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/cirurgia , Doenças Assintomáticas , Constrição , Procedimentos Endovasculares , Humanos , Masculino , Pessoa de Meia-Idade , Nefrectomia , Artéria Renal/diagnóstico por imagem , Artéria Renal/cirurgia , Veias Renais/diagnóstico por imagem , Veias Renais/cirurgia , Tentativa de Suicídio , Fatores de Tempo , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/cirurgia
4.
J Exp Bot ; 72(7): 2334-2355, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33315095

RESUMO

Phenolamides represent a family of specialized metabolites, consisting of the association of hydroxycinnamic acid derivatives with aliphatic or aromatic amines. Since the discovery of the first phenolamide in the late 1940s, decades of phytochemical analyses have revealed a high structural diversity for this family and a wide distribution in the plant kingdom. The occurrence of structurally diverse phenolamides in almost all plant organs has led to early hypotheses on their involvement in floral initiation and fertility, as well as plant defense against biotic and abiotic stress. In the present work, we critically review the literature ascribing functional hypotheses to phenolamides and recent evidence on the control of their biosynthesis in response to biotic stress. We additionally provide a phylogenetic analysis of the numerous N-hydroxycinnamoyltransferases involved in the synthesis of phenolamides and discuss the potential role of other enzyme families in their diversification. The data presented suggest multiple evolutionary events that contributed to the extension of the taxonomic distribution and diversity of phenolamides.


Assuntos
Ácidos Cumáricos , Plantas , Evolução Biológica , Filogenia , Plantas/genética
5.
Environ Microbiol ; 19(7): 2604-2615, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28371112

RESUMO

The Périgord black truffle (Tuber melanosporum Vittad.) is a heterothallic ascomycete that establishes ectomycorrhizal symbiosis with trees and shrubs. Small-scale genetic structures of female genotypes in truffle orchards are known, but it has not yet been studied in male genotypes. In this study, our aim was to characterize the small-scale genetic structure of both male and female genotypes over five years in an orchard to better understand the T. melanosporum sexual reproduction strategy, male genotype dynamics, and origins. Two-hundred forty-one ascocarps, 475 ectomycorrhizas, and 20 soil cores were harvested and genotyped using microsatellites and mating type genes. Isolation by distance analysis revealed pronounced small-scale genetic structures for both female and male genotypes. The genotypic diversity was higher for male than female genotypes with numerous small size genotypes suggesting an important turnover due to ascospore recruitment. Larger and perennial female and male genotypes were also detected. Only three genotypes (1.5%) were found as both female and male genotypes (hermaphrodites) while most were detected only as female or male genotype (dioecy). Our results suggest that germinating ascospores act as male genotypes, but we also proposed that soil mycelium could be a reservoir of male genotypes.


Assuntos
Ascomicetos/fisiologia , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Genótipo , Repetições de Microssatélites , Reprodução , Microbiologia do Solo , Simbiose
6.
Catheter Cardiovasc Interv ; 88(3): 358-66, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26650913

RESUMO

OBJECTIVES: This observational study assessed the 9-month clinical outcomes in an « all comers ¼ population with a focus on patients with atrial fibrillation (AF) after thin strut bare metal stenting. BACKGROUND: Drug eluting stent (DES) implantation is the treatment of choice for coronary artery disease (CAD) leaving only marginal indications for the use of bare metal stents (BMS). However, selected treatment populations with DES contraindications such as patients who cannot sustain 6-12 months of dual antiplatelet therapy (DAPT) remain candidates for BMS implantations. METHODS: Thin strut bare metal stenting in a priori defined subgroups were investigated in a non-randomized, international, multicenter «all comers¼ observational study. Primary endpoint was the 9-month TLR rate whereas secondary endpoints included the 9-month MACE and procedural success rates. RESULTS: A total of 783 patients of whom 98 patients had AF underwent BMS implantation. Patient age was 70.4 ± 12.8 years. Cardiovascular risk factors in the overall population were male gender (78.2%, 612/783), diabetes (25.2%, 197/783), hypertension (64.1%, 502/783), cardiogenic shock (4.9%, 38/783) and end stage renal disease (4.9%, 38/783). In-hospital MACE was 4.1% (30/783) in the overall population. The 9-month TLR rate was 4.5% (29/645) in the non-AF group and 3.3% (3/90) in the AF group (P = 0.613). At 9 months, the MACE rate in the AF-group and non-AF group was not significantly different either (10.7%, 69/645 vs. 6.7%, 6/90; P = 0.237). Accumulated stroke rates were 0.3% (2/645) in the non-AF subgroup at baseline and 1.1% (1/90) in the AF subgroup (P = 0.264). CONCLUSION: Bare metal stenting in AF patients delivered acceptably low TLR and MACE rates while having the benefit of a significantly shorter DAPT duration in a DES dominated clinical practice. © 2015 Wiley Periodicals, Inc.


Assuntos
Fibrilação Atrial/etiologia , Doença da Artéria Coronariana/terapia , Metais , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Stents , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Ásia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/mortalidade , Fibrilação Atrial/terapia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/mortalidade , Quimioterapia Combinada , Europa (Continente) , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Intervenção Coronária Percutânea/mortalidade , Inibidores da Agregação Plaquetária/administração & dosagem , Desenho de Prótese , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
7.
J Theor Biol ; 402: 144-57, 2016 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-27164436

RESUMO

In plants, the partitioning of carbon resources between growth and defense is detrimental for their development. From a metabolic viewpoint, growth is mainly related to primary metabolism including protein, amino acid and lipid synthesis, whereas defense is based notably on the biosynthesis of a myriad of secondary metabolites. Environmental factors, such as nitrate fertilization, impact the partitioning of carbon resources between growth and defense. Indeed, experimental data showed that a shortage in the nitrate fertilization resulted in a reduction of the plant growth, whereas some secondary metabolites involved in plant defense, such as phenolic compounds, accumulated. Interestingly, sucrose, a key molecule involved in the transport and partitioning of carbon resources, appeared to be under homeostatic control. Based on the inflow/outflow properties of sucrose homeostatic regulation we propose a global model on how the diversion of the primary carbon flux into the secondary phenolic pathways occurs at low nitrate concentrations. The model can account for the accumulation of starch during the light phase and the sucrose remobilization by starch degradation during the night. Day-length sensing mechanisms for variable light-dark regimes are discussed, showing that growth is proportional to the length of the light phase. The model can describe the complete starch consumption during the night for plants adapted to a certain light/dark regime when grown on sufficient nitrate and can account for an increased accumulation of starch observed under nitrate limitation.


Assuntos
Ciclo do Carbono/efeitos da radiação , Luz , Modelos Biológicos , Metabolismo Secundário/efeitos da radiação , Ciclo do Carbono/efeitos dos fármacos , Escuridão , Homeostase/efeitos dos fármacos , Homeostase/efeitos da radiação , Cinética , Nitratos/farmacologia , Fotoperíodo , Metabolismo Secundário/efeitos dos fármacos , Amido/metabolismo , Sacarose/metabolismo
8.
Mycorrhiza ; 26(5): 389-99, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26781750

RESUMO

Ectomycorrhizae create a multitrophic ecosystem formed by the association between tree roots, mycelium of the ectomycorrhizal fungus, and a complex microbiome. Despite their importance in the host tree's physiology and in the functioning of the ectomycorrhizal symbiosis, detailed studies on ectomycorrhiza-associated bacterial community composition and their temporal dynamics are rare. Our objective was to investigate the composition and dynamics of Tuber melanosporum ectomycorrhiza-associated bacterial communities from summer to winter seasons in a Corylus avellana tree plantation. We used 16S ribosomal RNA (rRNA)-based pyrosequencing to compare the bacterial community structure and the richness in T. melanosporum's ectomycorrhizae with those of the bulk soil. The T. melanosporum ectomycorrhizae harbored distinct bacterial communities from those of the bulk soil, with an enrichment in Alpha- and Gamma-proteobacteria. In contrast to the bacterial communities of truffle ascocarps that vastly varies in composition and richness during the maturation of the fruiting body and to those from the bulk soil, T. melanosporum ectomycorrhiza-associated bacterial community composition stayed rather stable from September to January. Our results fit with a recent finding from the same experimental site at the same period that a continuous supply of carbohydrates and nitrogen occurs from ectomycorrhizae to the fruiting bodies during the maturation of the ascocarps. We propose that this creates a stable niche in the ectomycorrhizosphere although the phenology of the tree changes.


Assuntos
Ascomicetos/fisiologia , Bactérias/classificação , Bactérias/genética , Micorrizas/fisiologia , Microbiologia do Solo , Ascomicetos/genética , Fenômenos Fisiológicos Bacterianos , Corylus/microbiologia , Corylus/fisiologia , DNA Bacteriano/genética , DNA Fúngico/genética , Regulação Bacteriana da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Raízes de Plantas/microbiologia , Fatores de Tempo
9.
Environ Microbiol ; 16(9): 2831-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24118660

RESUMO

Although truffles are cultivated since decades, their life cycle and the conditions stimulating ascocarp formation still remain mysterious. A role for bacteria in the development of several truffle species has been suggested but few is known regarding the natural bacterial communities of Périgord Black truffle. Thus, the aim of this study was to decipher the structure and the functional potential of the bacterial communities associated to the Black truffle in the course of its life cycle and along truffle maturation. A polyphasic approach combining 454-pyrosequencing of 16S rRNA gene, TTGE, in situ hybridization and functional GeoChip 3.0 revealed that Black truffle ascocarps provide a habitat to complex bacterial communities that are clearly differentiated from those of the surrounding soil and the ectomycorrhizosphere. The composition of these communities is dynamic and evolves during the maturation of the ascocarps with an enrichment of specific taxa and a differentiation of the gleba and peridium-associated bacterial communities. Genes related to nitrogen and sulphur cycling were enriched in the ascocarps. Together, these data paint a new picture of the interactions existing between truffle and bacteria and of the potential role of these bacteria in truffle maturation.


Assuntos
Agaricales , Ascomicetos , Bactérias/classificação , Ecossistema , Consórcios Microbianos , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Rizosfera , Análise de Sequência de DNA , Microbiologia do Solo
10.
New Phytol ; 199(1): 203-211, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23534902

RESUMO

Dead organic matter (OM) is a major source of nitrogen (N) for plants. The majority of plants support N uptake by symbiosis with arbuscular mycorrhizal (AM) fungi. Mineralization of N is regulated by microfauna, in particular, protozoa grazing on bacteria. We hypothesized that AM fungi and protozoa interactively facilitate plant N nutrition from OM. In soil systems consisting of an OM patch and a root compartment, plant N uptake and consequences for plant carbon (C) allocation were investigated using stable isotopes. Protozoa mobilized N by consuming bacteria, and the mobilized N was translocated via AM fungi to the host plant. The presence of protozoa in both the OM and root compartment stimulated photosynthesis and the translocation of C from the host plant via AM fungi into the OM patch. This stimulated microbial activity in the OM patch, plant N uptake from OM and doubled plant growth. The results indicate that protozoa increase plant growth by both mobilization of N from OM and by protozoa-root interactions, resulting in increased C allocation to roots and into the rhizosphere, thereby increasing plant nutrient exploitation. Hence, mycorrhizal plants need to interact with protozoa to fully exploit N resources from OM.


Assuntos
Micorrizas/metabolismo , Nitrogênio/metabolismo , Raízes de Plantas/microbiologia , Plantago/crescimento & desenvolvimento , Plantago/microbiologia , Microbiologia do Solo , Simbiose , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Isótopos de Carbono/análise , Isótopos de Carbono/metabolismo , Hifas/metabolismo , Minerais/metabolismo , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Fotossíntese , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantago/metabolismo
11.
New Phytol ; 199(1): 176-187, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23574460

RESUMO

The genetic structure of ectomycorrhizal (ECM) fungal populations results from both vegetative and sexual propagation. In this study, we have analysed the spatial genetic structure of Tuber melanosporum populations, a heterothallic ascomycete that produces edible fruit bodies. Ectomycorrhizas from oaks and hazels from two orchards were mapped and genotyped using simple sequence repeat markers and the mating type locus. The distribution of the two T. melanosporum mating types was also monitored in the soil. In one orchard, the genetic profiles of the ascocarps were compared with those of the underlying mycorrhizas. A pronounced spatial genetic structure was found. The maximum genet sizes were 2.35 and 4.70 m in the two orchards, with most manifesting a size < 1 m. Few genets persisted throughout two seasons. A nonrandom distribution pattern of the T. melanosporum was observed, resulting in field patches colonized by genets that shared the same mating types. Our findings suggest that competition occurs between genets and provide basic information on T. melanosporum propagation patterns that are relevant for the management of productive truffle orchards.


Assuntos
Ascomicetos/genética , Repetições de Microssatélites , Variação Genética , Genética Populacional , Itália , Micorrizas/genética , Plantas Comestíveis/genética , Quercus/microbiologia , Reprodução Assexuada/genética , Microbiologia do Solo
12.
Ann Vasc Surg ; 27(6): 719-26, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23880454

RESUMO

BACKGROUND: This study compares the neurologic evolution and number of restenoses between 2 groups of patients who underwent internal carotid endarterectomy with patch angioplasty (CEP): one group with systematic intraoperative completion arteriography (CA) and another group without. METHODS: This monocentric retrospective study was performed from January 2000 to December 2008 on 559 consecutive CEPs; 179 were controlled with CA and 380 were not. Surgery was chosen for patients with greater than 50% symptomatic or greater than 60% asymptomatic stenosis (North American Symptomatic Carotid Endarterectomy Trial criteria). Each patient's neurologic and ultrasound status was followed-up postoperatively, and at 3 months in the presence of neurologic symptoms, and at the end of the follow-up. Residual stenosis and restenosis were defined by a reduction in diameter of greater than 50% or a maximal systolic velocity greater than 150 cm/s. The surgical team included 4 vascular surgeons: 2 experienced surgeons who did not perform CA, 1 experienced surgeon monitoring surgical trainees, and 1 who had little experience performing CA. RESULTS: In both groups, the patients were comparable in terms of cardiovascular risks, except for age, gender, statin treatment, and neoplastic medical history. During the first 30 postoperative days, the mean rate of cerebrovascular accident (CVA) and death was 0.4%. In the CA group, 1 incidence (0.6%) of partial monocular blindness occurred, and in the no-CA group, 1 incidence (0.2%) of hemorrhagic CVA and 3 (0.5%) transient ischemic attacks (TIAs) occurred. One of these TIAs resulted from a residual stenosis. Mean follow-up was 41 months. During this time, 6 ipsilateral neurologic accidents occurred in the CA group (1 ischemic CVA, 3 TIAs, 1 partial monocular blindness, and 1 hemorrhagic CVA), whereas 10 occurred in the no CA group (1 ischemic CVA, 4 TIAs, 3 hemorrhagic CVAs, 1 partial monocular blindness, and 1 recurrence of vertebrobasilar insufficiency). The combined morbidity and mortality rates in the 2 groups were 3.3% and 2.8%, respectively (P > 0.05). Two residual stenoses (0.5%) and 6 significant restenoses (1.6%) were diagnosed in the no-CA group; 4 significant restenoses (2.2%) occurred in the CA group (P > 0.05). CONCLUSIONS: When performed by experienced surgeons, systematic intraoperative CA does not reduce the incidence of ipsilateral neurologic complications after CEP. Systematic intraoperative arteriography enables surgical trainees to obtain results as satisfactory as those of experienced surgeons.


Assuntos
Angiografia , Angioplastia/métodos , Estenose das Carótidas/diagnóstico por imagem , Endarterectomia das Carótidas/métodos , Testes Obrigatórios/métodos , Cuidados Pós-Operatórios/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/cirurgia , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/prevenção & controle
13.
J Exp Bot ; 63(16): 5815-27, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22987839

RESUMO

Solute active transport or exclusion by plants can be identified by the values of the Transpiration Stream Concentration Factor (TSCF=xylem:solution solute concentration ratio). The aim of this study was to estimate this parameter for Ni uptake by the Ni-hyperaccumulator Leptoplax emarginata or the Ni-excluder Triticum aestivum cultivar 'Fidel'. The Intact Plant TSCF for nickel (IPTSCF(Ni)) was calculated as the ratio between the nickel mass accumulation in the leaves and the nickel concentration in solution per volume of water transpired. Predominantly, Ni active transport occurred for L. emarginata, with IPTSCF(Ni) values of 4.7-7.2 and convective component proportions of the root Ni uptake flow of only 15-20% for a range of Ni concentrations in solutions of 2-16 µmol Ni l(-1), regardless of the growth period and the time of Ni uptake. Hyperaccumulator roots were permeable to both water and nickel (mean reflection coefficient for Ni, σ(Ni), of 0.06), which was mainly attributed to an absence of exodermis. Results provide a new view of the mechanisms of Ni hyperaccumulation. By contrast, the wheat excluder was characterized by an extremely low mean IPTSCF(Ni) value of 0.006, characterizing a predominantly Ni sequestration in roots. From a methodological viewpoint, the 'microscopic' TSCF(Ni), measured directly on excised plants was 2.4 times larger than its recommended 'macroscopic' IPTSCF(Ni) counterpart. Overall, IPTSCF and σ determined on intact transpiring plants appeared to be very useful biophysical parameters in the study of the mechanisms involved in metal uptake and accumulation by plants, and in their modelling.


Assuntos
Biofísica/métodos , Brassicaceae/metabolismo , Níquel/metabolismo , Triticum/metabolismo , Transporte Biológico , Brassicaceae/química , Cinética , Níquel/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Transpiração Vegetal , Triticum/química
14.
Metabolites ; 12(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35736416

RESUMO

Tomato plants are attacked by a variety of herbivore pests and among them, the leafminer Tuta absoluta, which is currently a major threat to global tomato production. Although the commercial tomato is susceptible to T. absoluta attacks, a better understanding of the defensive plant responses to this pest will help in defining plant resistance traits and broaden the range of agronomic levers that can be used for an effective integrated pest management strategy over the crop cycle. In this study, we developed an integrative approach combining untargeted metabolomic and transcriptomic analyses to characterize the local and systemic metabolic responses of young tomato plants to T. absoluta larvae herbivory. From metabolomic analyses, the tomato response appeared to be both local and systemic, with a local response in infested leaves being much more intense than in other parts of the plant. The main response was a massive accumulation of phenolamides with great structural diversity, including rare derivatives composed of spermine and dihydrocinnamic acids. The accumulation of this family of specialized metabolites was supported by transcriptomic data, which showed induction of both phenylpropanoid and polyamine precursor pathways. Moreover, our transcriptomic data identified two genes strongly induced by T. absoluta herbivory, that we functionally characterized as putrescine hydroxycinnamoyl transferases. They catalyze the biosynthesis of several phenolamides, among which is caffeoylputrescine. Overall, this study provided new mechanistic clues of the tomato/T. absoluta interaction.

15.
Biomed Pharmacother ; 131: 110762, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33152925

RESUMO

Phenolamides constitute a family of metabolites, widely represented in the plant kingdom, that can be found in all plant organs with a predominance in flowers and pollen grains. They represent a large and structurally diverse family, resulting from the association of phenolic acids with aliphatic or aromatic amines. Initially revealed as active compounds in several medicinal plant extracts, phenolamides have been extensively studied for their health-promoting and pharmacological properties. Indeed, phenolamides have been shown to exhibit antioxidant, anti-inflammatory, anti-cancer and antimicrobial properties, but also protective effects against metabolic syndrome and neurodegenerative diseases. The purpose of this review is to summarise this large body of literature, including in vitro and in vivo studies, by describing the diversity of their biological properties and our actual knowledge of the molecular mechanisms behind them. With regard to their considerable pharmacological interest, the question of industrial production is also tackled through chemical and biological syntheses in engineered microorganisms. The diversity of biological activities already described, together with the active discovery of the broad structural diversity of this metabolite family, make phenolamides a promising source of new active compounds on which future studies should be focused.


Assuntos
Amidas/farmacologia , Fenóis/farmacologia , Plantas Medicinais/química , Amidas/química , Amidas/isolamento & purificação , Animais , Humanos , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia
16.
J Exp Bot ; 60(15): 4301-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19741002

RESUMO

Plants allocate internal resources to fulfil essential, yet possibly conflicting, demands such as defence or growth, as hypothesized by the 'growth-differentiation balance theory' (GDB). This trade-off was examined in young tomato plants grown for 25 d using the nutrient film technique with seven nitrate concentrations ([NO(3)]). The modification of primary (growth-related: organic acids, carbohydrates) and secondary (defence-related: phenolics) metabolite concentrations in leaves was assessed. Then a simple model was devised to simulate the trade-off between growth and secondary metabolism in response to N nutrition. N affected growth and metabolite concentrations in the leaves. Dry biomass, leaf area, and concentrations of nitrate and organic acid (malic, citric) increased with rising [NO(3)], up to a threshold, above which they remained constant. Starch, sucrose, and organic N concentrations were invariant with [NO(3)]. Glucose, fructose, and phenolic (chlorogenic acid, rutin, and kaempferol-rutinoside) concentrations were highest at lowest [NO(3)]. They declined progressively with rising [NO(3)] until a threshold, above which they remained constant. Model predictions are in phase with experimental phenolic concentration data although the simulated metabolic rates differ from the GDBH proposals depicted in the literature. From the model output it is shown that a careful definition of the C reserve compounds is required.


Assuntos
Metabolismo dos Carboidratos , Nitratos/metabolismo , Fenóis/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Modelos Biológicos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
17.
Coron Artery Dis ; 19(2): 89-97, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18300745

RESUMO

AIMS: The authors tested the value of stress single-photon emission computed tomography (SPECT) imaging performed systematically for detecting angiographic restenosis in asymptomatic patients who underwent direct percutaneous coronary intervention (PCI) for acute ST segment elevation myocardial infarction (STEMI). Angiographic restenosis of the infarct-related artery after direct PCI for STEMI is often silent and the strategy for follow-up evaluation of asymptomatic patients remains debated. METHODS: A total of 149 patients successfully treated by direct PCI (96% stenting) for STEMI with no symptoms during the follow-up systematically underwent both rest thallium 201/stress Tc 99m setamibi myocardial perfusion imaging and coronary angiogram at 6 months. Patients were followed up for 2.5+/-0.5 years after 6 months control for cardiac events. RESULTS: In the 149 patients, the sensitivity, specificity, positive and negative predictive values and accuracy of SPECT imaging were 48, 61, 35, 72 and 57%, respectively, for detecting binary angiographic restenosis defined as > or =50% diameter stenosis. Whether stress testing was maximal or performed after withheld anti-ischemic drugs did not improve the results. Reversible ischemia at SPECT in the infarct territory did not predict long-term cardiac events. CONCLUSION: These data suggest a poor correlation between stress SPECT imaging and angiographic restenosis at 6 months in patients treated by direct PCI for STEMI who remain asymptomatic at follow-up. The long-term clinical prognostic value of SPECT reversible ischemia in the infarct territory appears also limited in this peculiar subset of patients. These findings should be taken into account in the strategy of the clinical follow-up of this population.


Assuntos
Angioplastia Coronária com Balão/reabilitação , Reestenose Coronária/diagnóstico por imagem , Infarto do Miocárdio/cirurgia , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica , Valor Preditivo dos Testes , Prognóstico
18.
Plant Sci ; 277: 166-176, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30466582

RESUMO

BACKGROUND: The production of secondary metabolites through the culture of entire plants is of great interest. Soilless culture, such as hydroponics, enables the control of plant growth and metabolism. Specific environmental conditions must be developed to maximize the productivity of medicinal plants used as efficient natural bioreactors. METHODS: The nutrient solution of newly established hydroponic cultures ofDatura innoxia Mill. were inoculated with Agrobacterium rhizogenes (A.r.) wild strains (TR7, TR107, 11325 or 15834). Growth and the alkaloid contents of roots and aerial parts were analyzed. Axenic cultures were also performed with modified TR7 strains containing the egfp or gus reporter gene. In vitro isolated root cultures enabled the phenological and molecular demonstration of gene transfer. RESULTS: A.r.TR 7 led to a greater improvement in plant secondary metabolism and growth. Positive expression of the reporter genes occurred. Isolation and subculture of some of the roots of these plants showed a hairy root phenotype; molecular tests proved the transfer of bacterial genes into the roots isolated from the plants. CONCLUSIONS: Hyoscyamine and scopolamine productivity is enhanced after A.r. inoculation in the nutrient solution of hydroponic plants. Transformation events occur in the original roots of the plants. This leads to chimeric plants with a part of their roots harboring a hairy root phenotype. Such semi-composite plants could be used for successful specialized metabolite bioproduction in greenhouses.


Assuntos
Agrobacterium/patogenicidade , Alcaloides/metabolismo , Datura/metabolismo , Datura/microbiologia , Datura/crescimento & desenvolvimento , Hidroponia , Desenvolvimento Vegetal
19.
J Insect Physiol ; 99: 130-138, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28392206

RESUMO

The leafminer Tuta absoluta (Meyrick) is a major pest of the tomato crop and its development rate is known to decline when nitrogen availability for crop growth is limited. Because N limitation reduces plant primary metabolism but enhances secondary metabolism, one can infer that the slow larval development arises from lower leaf nutritive value and/or higher plant defence. As an attempt to study the first alternative, we examined the tomato-T. absoluta interaction in terms of resource supply by leaves and intake by larvae. Tomato plants were raised under controlled conditions on N-sufficient vs. N-limited complete nutrient solutions. Plants were kept healthy or artificially inoculated with larvae for seven days. Serial harvests were taken and the N, C, dry mass and water contents were determined in roots, stems and leaves. Leaf and mine areas were also measured and the N, C, dry mass and water surface densities were calculated in order to characterize the diet of the larvae. The infestation of a specific leaf lessened its local biomass by 8-26%, but this effect was undetectable at the whole plant scale. Infestation markedly increased resource density per unit leaf area (water, dry mass, C and N) suggesting that the insect induced changes in leaf composition. Nitrogen limitation lessened whole plant growth (by 50%) and infested leaflet growth (by 32-44%). It produced opposite effects on specific resource density per unit area, increasing that of dry mass and C while decreasing water and N. These changes were ineffective on insect mining activity, but slowed down larval development. Under N limitation, T. absoluta consumed less water and N but more dry mass and C. The resulting consequences were a 50-70% increase of C:N stoichiometry in their diet and the doubling of faeces excretion. The observed limitation of larval development is therefore consistent with a trophic explanation caused by low N and/or water intakes.


Assuntos
Mariposas/fisiologia , Nitrogênio/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Animais , Carbono/metabolismo , Larva/crescimento & desenvolvimento , Larva/fisiologia , Solanum lycopersicum/química , Mariposas/crescimento & desenvolvimento , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Água
20.
Coron Artery Dis ; 17(3): 261-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16728877

RESUMO

OBJECTIVES: No reflow has been reported in 12-30% of the patients directly revascularized by angioplasty for acute ST elevation myocardial infarction with the highest incidence after primary stenting in patients with initial thrombolysis in myocardial infarction (TIMI) grade 0 flow. We hypothesized that a minimalist immediate mechanical intervention (MIMI) based on the use of very small size balloons to avoid both large dissection and distal embolization may be sufficient to restore flow in emergency and that recanalization may be sustained by maximized antithrombotic regimen (abcximab, clopidogrel, aspirin and heparin) allowing one to postpone stenting in better conditions. METHODS: MIMI was performed in 93 patients for ST elevation myocardial infarction with initial TIMI grade 0 flow. RESULTS: MIMI resulted in a TIMI grade 3 flow in 77/93 patients (83%). Immediate stenting was performed in the 16 patients with failed MIMI and resulted in a TIMI grade 3 flow in nine (56%). The residual stenosis after MIMI was 81+/-11% and ST segment resolution (> or =50%) at 1 h after reperfusion was obtained in 84%. Stenting was performed the following days in 52 patients with a post-stenting TIMI grade 3 flow in 50 (96%; 100% when stenting done beyond 24 h). No reocclusion occurred between MIMI and stenting. Among the 25 patients without stenting, six had mild stenosis at control angiogram and underwent medical treatment whereas 19 had multiple vessel disease and underwent bypass surgery. CONCLUSIONS: MIMI combined with maximized antithrombotic therapy results in immediate and sustained recanalization with a high rate of ST resolution in a majority of patients with ST elevation myocardial infarction. This approach allows one to postpone stenting in more stable conditions with a low rate of TIMI flow deterioration or to schedule more appropriate medical or surgical alternative management.


Assuntos
Angioplastia Coronária com Balão/métodos , Sistema de Condução Cardíaco/fisiopatologia , Infarto do Miocárdio/terapia , Idoso , Angioplastia Coronária com Balão/instrumentação , Implante de Prótese Vascular/instrumentação , Cateterismo Cardíaco , Angiografia Coronária , Circulação Coronária , Estenose Coronária/complicações , Estenose Coronária/diagnóstico por imagem , Estenose Coronária/fisiopatologia , Estenose Coronária/terapia , Trombose Coronária/complicações , Trombose Coronária/diagnóstico por imagem , Trombose Coronária/fisiopatologia , Trombose Coronária/terapia , Eletrocardiografia , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica , Estudos Prospectivos , Projetos de Pesquisa , Stents , Resultado do Tratamento
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