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1.
Front Psychol ; 14: 1160210, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078253

RESUMEN

Objectives: To perform a detailed description of executive functioning following moderate-to-severe childhood traumatic brain injury (TBI), and to study demographic and severity factors influencing outcome. Methods: A convenience sample of children/adolescents aged 7-16 years, referred to a rehabilitation department after a TBI (n = 43), was compared to normative data using a newly developed neuropsychological test battery (Child Executive Functions Battery-CEF-B) and the BRIEF. Results: Performance in the TBI group was significantly impaired in most of the CEF-B subtests, with moderate to large effect sizes. Regarding everyday life, patients were significantly impaired in most BRIEF clinical scales, either in parent or in teacher reports. Univariate correlations in the TBI group did not yield significant correlations between the CEF-B and socio-economic status, TBI severity, age at injury, or time since injury. Conclusion: Executive functioning is severely altered following moderate-to-severe childhood TBI and is best assessed using a combination of developmentally appropriate neuropsychological tests and behavioral ratings to provide a comprehensive understanding of children's executive functions.

2.
Plant Sci ; 307: 110905, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33902861

RESUMEN

Contrary to animals, little is known in plants about enzymes able to produce fatty acid epoxides. In our attempt to find and characterize a new fatty acid epoxygenase in Arabidopsis thaliana, data mining brought our attention on CYP77B1. Modification of the N-terminus was necessary to get enzymatic activity after heterologous expression in yeast. The common plant fatty acid C18:2 was converted into the diol 12,13-dihydroxy-octadec-cis-9-enoic acid when incubated with microsomes of yeast expressing modified CYP77B1 and AtEH1, a soluble epoxide hydrolase. This diol originated from the hydrolysis by AtEH1 of the epoxide 12,13-epoxy-octadec-cis-9-enoic acid produced by CYP77B1. A spatio-temporal study of CYP77B1 expression performed with RT-qPCR revealed the highest level of transcripts in flower bud while, in open flower, the enzyme was mainly present in pistil. CYP77B1 promoter-driven GUS expression confirmed reporter activities in pistil and also in stamens and petals. In silico co-regulation data led us to hypothesize that CYP77B1 could be involved in cutin synthesis but when flower cutin of loss-of-function mutants cyp77b1 was analyzed, no difference was found compared to cutin of wild type plants. Phylogenetic analysis showed that CYP77B1 is strictly conserved in flowering plants, suggesting a specific function in this lineage.


Asunto(s)
Arabidopsis/enzimología , Sistema Enzimático del Citocromo P-450/metabolismo , Compuestos Epoxi/metabolismo , Ácidos Grasos/metabolismo , Magnoliopsida/enzimología , Oxigenasas/metabolismo
3.
Plant J ; 97(3): 447-459, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30347487

RESUMEN

All present-day mitochondria originate from a single endosymbiotic event that gave rise to the last eukaryotic common ancestor more than a billion years ago. However, to date, many aspects of mitochondrial evolution have remained unresolved. Comparative genomics and proteomics have revealed a complex evolutionary origin for many mitochondrial components. To understand the evolution of the respiratory chain, we have examined both the components and the mechanisms of the assembly pathway of complex I. Complex I represents the first enzyme in the respiratory chain, and complex I deficiencies have dramatic consequences in both animals and plants. The complex is located in the mitochondrial inner membrane and possesses two arms: one embedded in the inner membrane and one protruding in the matrix. Here, we describe the assembly pathway of complex I in the model plant Arabidopsis thaliana. Using a proteomics approach called complexome profiling, we have resolved the different steps in the assembly process in plants. We propose a model for the stepwise assembly of complex I, including every subunit. We then compare this pathway with the corresponding pathway in humans and find that complex I assembly in plants follows a different, and likely ancestral, pathway compared with the one in humans. We show that the main evolutionary changes in complex I structure and assembly in humans occurred at the level of the membrane arm, whereas the matrix arm remained rather conserved.


Asunto(s)
Arabidopsis/enzimología , Complejo I de Transporte de Electrón/metabolismo , Arabidopsis/genética , Transporte de Electrón , Complejo I de Transporte de Electrón/genética , Evolución Molecular , Mitocondrias/metabolismo , Proteómica
4.
New Phytol ; 215(1): 173-186, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28497532

RESUMEN

Epoxide hydrolases (EHs) are present in all living organisms. They have been extensively characterized in mammals; however, their biological functions in plants have not been demonstrated. Based on in silico analysis, we identified AtEH1 (At3g05600), a putative Arabidopsis thaliana epoxide hydrolase possibly involved in cutin monomer synthesis. We expressed AtEH1 in yeast and studied its localization in vivo. We also analyzed the composition of cutin from A. thaliana lines in which this gene was knocked out. Incubation of recombinant AtEH1 with epoxy fatty acids confirmed its capacity to hydrolyze epoxides of C18 fatty acids into vicinal diols. Transfection of Nicotiana benthamiana leaves with constructs expressing AtEH1 fused to enhanced green fluorescent protein (EGFP) indicated that AtEH1 is localized in the cytosol. Analysis of cutin monomers in loss-of-function Ateh1-1 and Ateh1-2 mutants showed an accumulation of 18-hydroxy-9,10-epoxyoctadecenoic acid and a concomitant decrease in corresponding vicinal diols in leaf and seed cutin. Compared with wild-type seeds, Ateh1 seeds showed delayed germination under osmotic stress conditions and increased seed coat permeability to tetrazolium red. This work reports a physiological role for a plant EH and identifies AtEH1 as a new member of the complex machinery involved in cutin synthesis.


Asunto(s)
Proteínas de Arabidopsis/fisiología , Arabidopsis/enzimología , Epóxido Hidrolasas/fisiología , Lípidos de la Membrana/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/análisis , Proteínas de Arabidopsis/genética , Citosol/metabolismo , Epóxido Hidrolasas/análisis , Epóxido Hidrolasas/genética , Funciones de Verosimilitud , Filogenia , Alineación de Secuencia
5.
Nat Commun ; 8: 14713, 2017 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-28270693

RESUMEN

Lignin, one of the most abundant biopolymers on Earth, derives from the plant phenolic metabolism. It appeared upon terrestrialization and is thought critical for plant colonization of land. Early diverging land plants do not form lignin, but already have elements of its biosynthetic machinery. Here we delete in a moss the P450 oxygenase that defines the entry point in angiosperm lignin metabolism, and find that its pre-lignin pathway is essential for development. This pathway does not involve biochemical regulation via shikimate coupling, but instead is coupled with ascorbate catabolism, and controls the synthesis of the moss cuticle, which prevents desiccation and organ fusion. These cuticles share common features with lignin, cutin and suberin, and may represent the extant representative of a common ancestor. Our results demonstrate a critical role for the ancestral phenolic metabolism in moss erect growth and cuticle permeability, consistent with importance in plant adaptation to terrestrial conditions.


Asunto(s)
Bryopsida/metabolismo , Lignina/metabolismo , Fenoles/metabolismo , Ácido Ascórbico/metabolismo , Evolución Biológica , Bryopsida/genética , Sistema Enzimático del Citocromo P-450/genética , Desecación , Embryophyta , Técnicas de Inactivación de Genes , Magnoliopsida/metabolismo , Lípidos de la Membrana , Componentes Aéreos de las Plantas/metabolismo , Plantas Modificadas Genéticamente
6.
Phytochemistry ; 117: 388-399, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26164240

RESUMEN

The role and fate of Jasmonoyl-Phenylalanine (JA-Phe), an understudied conjugate in the jasmonate pathway remain to be unraveled. We addressed here the possibility of JA-Phe oxidative turnover by cytochrome P450s of the CYP94 family. Leaf wounding or fungal infection in Arabidopsis resulted in accumulation of JA-Phe, 12-hydroxyl (12OH-JA-Phe) and 12-carboxyl (12COOH-JA-Phe) derivatives, with patterns differing from those previously described for Jasmonoyl-Isoleucine. In vitro, yeast-expressed cytochromes P450 CYP94B1, CYP94B3 and CYP94C1 differentially oxidized JA-Phe to 12-hydroxyl, 12-aldehyde and 12-carboxyl derivatives. Furthermore, a new aldehyde jasmonate, 12CHO-JA-Ile was detected in wounded plants. Metabolic analysis of CYP94B3 and CYP94C1 loss- and gain-of-function plant lines showed that 12OH-JA-Phe was drastically reduced in cyp94b3 but not affected in cyp94c1, while single or double mutants lacking CYP94C1 accumulated less 12COOH-JA-Phe than WT plants. This, along with overexpressing lines, demonstrates that hydroxylation by CYP94B3 and carboxylation by CYP94C1 accounts for JA-Phe turnover in planta. Evolutionary study of the CYP94 family in the plant kingdom suggests conserved roles of its members in JA conjugate homeostasis and possibly in adaptative functions. Our work extends the range and complexity of JA-amino acid oxidation by multifunctional CYP94 enzymes in response to environmental cues.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ciclopentanos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Isoleucina/análogos & derivados , Fenilalanina/análogos & derivados , Hojas de la Planta/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Sistema Enzimático del Citocromo P-450/genética , Flores/metabolismo , Isoleucina/metabolismo , Mutación , Oxidación-Reducción , Fenilalanina/metabolismo , Filogenia
7.
J Thorac Cardiovasc Surg ; 139(1): 198-208, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19709678

RESUMEN

OBJECTIVE: Transcatheter pulmonary valve insertion has recently emerged as an alternative to surgery. To extend its indications to patients with a large right ventricular outflow tract, we previously developed an intravascular device that reduces the diameter of the main pulmonary artery, allowing the insertion of available valved stents. Here we report its use in a model of animals with an enlarged right ventricular outflow tract and pulmonary valve incompetence. METHODS AND RESULTS: The study comprised 33 sheep that first underwent surgical enlargement of the main pulmonary artery. We then intended to implant a filler percutaneously, followed later by the insertion of a valve. Three animals died during the intermediate stage. The remainder were humanely killed either immediately (group 1, n = 6) or after a mean follow-up of 1 (group 2, n = 12) or 2 months (group 3, n = 12). Animals from groups 2 and 3 were equally divided into 2 subgroups according to the difference between diameters of the device inserted and the main pulmonary artery (A < 5 mm, B > or = 5 mm). Fillers were all inserted successfully (n = 30), although one embolized after its insertion (group 3A). A valved stent was implanted in all animals, but in 1 case a balloon ruptured during inflation of the stent leading to incomplete expansion and the death of the animal. Six animals, 5 of which were from group A, had pulmonary regurgitation after valve insertion. CONCLUSION: Pulmonary valve insertion is possible through a transcatheter technique using a pulmonary artery filler. Oversizing the device reduces the risk of embolization and paraprosthetic leak.


Asunto(s)
Prótesis Valvulares Cardíacas , Implantación de Prótesis/métodos , Arteria Pulmonar/patología , Animales , Cateterismo , Modelos Animales de Enfermedad , Insuficiencia de la Válvula Pulmonar/terapia , Ovinos , Stents
8.
Eur J Cardiothorac Surg ; 31(2): 236-41, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17222560

RESUMEN

OBJECTIVE: In presence of adequate pulmonary blood flow, patients presenting with unoperated or palliated pulmonary atresia with ventricular septal defect (PA/VSD) can reach adult age. However, they remain symptomatic with a limited life expectancy. METHODS: Since 1993, 27 patients underwent surgery for unrepaired PA/VSD. Median age was 20 (range: 15-43) years. Nineteen patients had 33 previous palliative procedures while eight were unoperated survivors. Major aortopulmonary collateral artery (MAPCA) had been observed in all but 2 and were still patent in 23. All bronchopulmonary segments were connected to the native pulmonary arteries (NPA) in 4 (type A), to both NPA and MAPCA in 18 (type B) and only to MAPCA in 5 (type C). The biventricular repair was performed in 17 patients: 3 type A, 12 type B and 2 type C. Ten patients underwent palliative procedure: eight aortopulmonary shunt, with unifocalisation in two and one right ventricle to NPA restrictive conduit. RESULTS: One (4%) hospital death occurred following the failure of a palliative procedure. No clinical improvement was observed in seven patients including one repaired and six palliated survivors. Two late cardiac death occurred 1 and 7 years after repair. At last visit, 15 of 16 repaired survivors were in NYHA class I or II. Only one patient awaits septation, while eight other with subsequent palliation were considered not repairable. CONCLUSION: The outcome was encouraging in patients who were eligible for completed biventricular repair. Although considered as unique alternative to cardiopulmonary transplantation, the justification for palliative surgery to improve pulmonary blood flow remains to be established.


Asunto(s)
Defectos del Tabique Interventricular/cirugía , Atresia Pulmonar/cirugía , Adolescente , Adulto , Defecto del Tabique Aortopulmonar/diagnóstico por imagen , Defecto del Tabique Aortopulmonar/cirugía , Defectos del Tabique Interventricular/diagnóstico por imagen , Humanos , Cuidados Paliativos/métodos , Atresia Pulmonar/diagnóstico por imagen , Reoperación , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
9.
J Thorac Cardiovasc Surg ; 131(5): 1130-5, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16678600

RESUMEN

BACKGROUND: Pulmonary artery banding is proposed as a first palliation in infants with complex congenital heart disease and high pulmonary blood flow. In addition, it may be used to retrain the left ventricle. Optimal tightening may be difficult to obtain, leading to reoperation. An implantable device for pulmonary artery banding with telemetric control was recently developed allowing for repeated adjustments, but it is presently limited to patients weighing less than 20 kg. In large animals, we tested an off-label adjustable gastric banding system for pulmonary artery banding. METHODS AND RESULTS: Fourteen ewes weighing 50 to 75 kg underwent implantation of the Lap-Band device (BioEnterics Corp, Santa Barbara, Calif) around the main pulmonary artery through a left thoracotomy. All had functional evaluation with progressive occlusion and opening of the device at implantation and every 2 weeks until sacrifice immediately after implantation (group 1, n = 8), at 1 month (group 2, n = 3), at 3 months (group 3, n = 3), or death. Invasive pressure measurements in the right ventricle and aorta were carried out each time. Devices were easily implanted in all animals. Progressive occlusion and reopening were possible in all animals during each time point. Two animals died of right heart failure related to excessive tightening of the band. Retrieval of the device without any major damage was possible in 12 of 14 animals. CONCLUSION: With this implantable device, we were able to adjust the pulmonary artery diameter in animals. Patients requiring left ventricle retraining and weighing more than 30 kg would benefit from the device's use in humans.


Asunto(s)
Materiales Biocompatibles , Arteria Pulmonar/cirugía , Elastómeros de Silicona , Procedimientos Quirúrgicos Vasculares/instrumentación , Animales , Estudios de Factibilidad , Femenino , Hemodinámica , Ovinos
10.
Pediatr Res ; 59(6): 773-7, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16641203

RESUMEN

This study was performed to assess a new vascular stent graft as an expandable valved conduit for right ventricular outflow tract (RVOT) reconstruction in sheep. Conduits were constructed by sewing an 18-mm valved conduit inside a stent. Crimped to 16 mm, they were implanted either under or without extracorporeal circulation in seven (group A) and in five (group B) sheep, respectively. Six weeks and 3 mo after their insertion, conduits were dilated intraluminally. A valved stent was implanted percutaneously into conduits before they were killed. Two animals from group A recovered normally, whereas five animals had a complicated postoperative course. In group B, one died acutely due to kinking of the conduit. Balloon dilatations were performed in all surviving animals. First dilatations had a slight impact on valvular function in all animals but one, whereas second dilatations led to significant PR in all. Transcatheter valve implantation was performed successfully. When animals were killed, no bleeding was found around the surgically implanted device. In conclusion, we designed a biologic valved conduit for RVOT reconstruction that can be dilated sequentially to follow animal growth. This new device can have tremendous applications in children with congenital heart diseases involving the RVOT.


Asunto(s)
Ventrículos Cardíacos/cirugía , Arteria Pulmonar/cirugía , Animales , Autopsia , Cateterismo , Bovinos , Ventrículos Cardíacos/patología , Hemodinámica , Arteria Pulmonar/patología , Ovinos
11.
J Thorac Cardiovasc Surg ; 129(6): 1371-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15942580

RESUMEN

OBJECTIVE: Perioperative hypothermia might be detrimental to the patient undergoing off-pump coronary artery bypass surgery. We assessed the efficacy of the Allon thermoregulation system (MTRE Advanced Technologies Ltd, Or-Akiva, Israel) compared with that of routine thermal care in maintaining normothermia during and after off-pump coronary artery bypass surgery. METHODS: Patients undergoing off-pump coronary artery bypass surgery were perioperatively and randomly warmed with the 2 techniques (n = 45 per group). Core temperature, hemodynamics, and troponin I, interleukin 6, interleukin 8, and interleukin 10 blood levels were assessed. RESULTS: The mean temperature of the patients in the Allon thermoregulation system group (AT group) was significantly ( P < .005) higher than that of the patients receiving routine thermal care (the RTC group); less than 40% of the latter reached 36 degrees C compared with 100% of the former. The cardiac index was higher and the systemic vascular resistance was lower ( P < .05) by 16% and 25%, respectively, in the individuals in the AT group compared with in the individuals in the RTC group during the 4 postoperative hours. End-of-surgery interleukin 6 levels and 24-hour postoperative troponin I levels were significantly ( P < .01) lower in the patients in the AT group than in the RTC group. The RTC group's troponin levels closely correlated with their interleukin 6 levels at the end of the operation ( R = 0.51, P = .002). CONCLUSIONS: Unlike routine thermal care, the Allon thermoregulation system maintains core normothermia in more than 80% of patients undergoing off-pump coronary artery bypass surgery. Normothermia is associated with better cardiac and vascular conditions, a lower cardiac injury rate, and a lower inflammatory response. The close correlation between the increased interleukin 6 and troponin I levels in the routine thermal care group indicates a potential deleterious effect of lowered temperature on the patient's outcome.


Asunto(s)
Temperatura Corporal , Puente de Arteria Coronaria Off-Pump/efectos adversos , Hipertermia Inducida/métodos , Hipotermia/prevención & control , Anciano , Femenino , Cardiopatías/etiología , Cardiopatías/prevención & control , Humanos , Hipotermia/etiología , Masculino , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/inmunología , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos
12.
Eur Heart J ; 26(19): 2013-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15872031

RESUMEN

AIMS: The aim of the present study was to evaluate whether off-pump mini-invasive mitral valve replacement is possible after prior bioprosthetic mitral valve replacement in animals. METHODS AND RESULTS: To validate this concept for off-pump redo mitral valve insertion, we first replaced surgically mitral valves of six sheep under extracorporeal circulation using a Mosaïc valve. Prior to its insertion, we added a radio-opaque ring on its base to enhance its visualization under fluoroscopy. A bovine jugular valve mounted into a stent was then inserted off-pump through an opening of the atrial wall. Mitral valves were replaced successfully in all animals. Following the surgical valve insertion, mean left atrium and left ventricular end-diastolic pressures were 38 (22-42) and 18.8 mmHg (13-22), respectively. Angiography showed perfectly functioning valves, no subaortic valve obstruction, and a mild paravalvular leak in one animal. In one animal, we were unable to control the bleeding from the atrial opening. In this case, trans-atrial valvulation was not attempted. The off-pump valvular implantation was successful in the other five sheep. Haemodynamic data did not change after the insertion of valved stents. Implanted valves were all competent. The animal with the better haemodynamics was kept alive and is still alive 3 months after implantation. CONCLUSION: Surgically implanted bioprosthetic valves provide excellent support for off-pump insertion of a valved stent. Further experiments are necessary, in particular with appropriate valve size, before considering this approach for percutaneous mitral valvular replacement in patients with a dysfunctional bioprosthesis.


Asunto(s)
Bioprótesis , Puente de Arteria Coronaria Off-Pump/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Prótesis Valvulares Cardíacas , Válvula Mitral/cirugía , Toracotomía/métodos , Animales , Cateterismo Cardíaco/métodos , Supervivencia de Injerto , Hemodinámica/fisiología , Válvula Mitral/fisiología , Diseño de Prótesis , Falla de Prótesis , Reoperación/métodos , Ovinos , Stents
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