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1.
Tree Physiol ; 29(11): 1329-39, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19773340

RESUMO

Genotypic variability for productivity, water-use efficiency and leaf traits in 33 genotypes selected from an F1 progeny of Populus deltoides Bartr. ex Marsh x Populus trichocarpa L. was explored under optimal and moderate water-deficit conditions. Saplings of the 33 genotypes were grown in a two-plot open field at INRA Orléans (France) and coppiced every year. A moderate water deficit was induced during two successive years on one plot by withholding irrigation, while the second one remained irrigated (control). Stem biomass and leaf structure (e.g., specific leaf area and leaf area) were measured in 2004 and 2005 and functional leaf traits (e.g., carbon isotope discrimination, Delta) were measured only in 2004. Tolerance to water deficit was estimated at genotype level as the ability to limit losses in biomass production in water deficit versus control trees. Stem biomass, leaf structure and Delta displayed a significant genotypic variability whatever the irrigation regime. For all traits, genotype ranks remained stable across years for similar irrigation conditions. Carbon isotope discrimination scaled negatively with productivity and leaf nitrogen content in controls. The most productive genotypes were the least tolerant to moderate water deficit. No relationship was evidenced between Delta and the level of tolerance to water deficit. The relationships between traits evidenced in this collection of P. deltoides x P. trichocarpa F1 genotypes contrast with the ones that were previously detected in a collection of P. deltoides x Populus nigra L. cultivars tested in the same field trial.


Assuntos
Genótipo , Populus/genética , Água/metabolismo , Variação Genética , Hibridização Genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Populus/metabolismo , Estresse Fisiológico
2.
Rev Med Suisse ; 4(150): 793-6, 2008 Mar 26.
Artigo em Francês | MEDLINE | ID: mdl-18476649

RESUMO

The hybrid treatment of aortic aneurysms is indicated in patients having the ostia of supra aortic or visceral branches taken in to the aneurysm. Indeed, these lesions are not eligible for classic endovascular treatment because the existing endoprostheses cannot provide perfusion of the side branches without inducing major endoleaks. The surgical technique consists of 2 steps: firstly, a by-pass between normal aorta and the major aortic branches involved in the aneurysm is performed to guarantee the perfusion of the organs such as brain, bowel, and after endoprosthesis deployment. Secondly, the endoprosthesis is deployed using the classical technique to isolate the aneurysm. The hybrid approach provides safe and reliable treatment of complex aortic aneurysms with mortality and morbidity rate far below the classical open surgery.


Assuntos
Aneurisma Aórtico/terapia , Terapia Combinada , Humanos , Procedimentos Cirúrgicos Vasculares/métodos
3.
Rev Med Suisse ; 3(94): 110-2, 114, 2007 Jan 17.
Artigo em Francês | MEDLINE | ID: mdl-17354534

RESUMO

Following acute myocardial infarction, necrotic cardiac tissue is replaced by scar leading to ventricular remodeling and pump failure. Transplantation of autologous bone marrow-derived cells into the heart, early post-infarct, aims to prevent ventricular remodeling. This strategy has been evaluated in four controlled, randomized clinical trials, which provided mixed results. A transient improvement in ventricular function was observed in one trial, and a modest improvement (the duration of which remains to be determined) in an additional trial, whereas two trials showed negative results. A modest benefit of bone marrow cell transplantation was also observed in patients with chronic ischemic heart disease. Despite mixed results reported so far, cell therapy of heart disease still is in its infancy and has considerable room for improvement.


Assuntos
Transplante de Medula Óssea , Infarto do Miocárdio/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos
4.
Biochimie ; 74(1): 53-6, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1576209

RESUMO

Alpha- and beta-D-galactosidases were characterized from a hydroalcoholic extract of wheat germ (Triticum vulgare). Kinetic constants (Vmax and KM) and the optimal pHs for the hydrolysis of p-nitrophenyl galactopyranosides by both enzymes were determined. These enzymes presented a high stability in hydroalcoholic medium and were inhibited by iodoacetamide and sodium p-hydroxy-mercuribenzoate.


Assuntos
Galactosidases/análise , Acetatos/química , Ácido Acético , Etanol/química , Concentração de Íons de Hidrogênio , Temperatura , Triticum
5.
Biochimie ; 79(1): 3-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9195039

RESUMO

The virulence genes of Agrobacterium tumefaciens are specifically activated by plant phenolic compounds and allow this organism to genetically transform plant cells. New types of phenolic compounds, three phenol amides derived from syringic acid, were synthesized. Introduction of an amide group in syringic acid strongly enhances its vir gene inducing activity.


Assuntos
Agrobacterium tumefaciens/efeitos dos fármacos , Amidas/química , Ácido Gálico/análogos & derivados , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Plantas Geneticamente Modificadas , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/patogenicidade , Alquilação , Ácido Gálico/química , Genes Bacterianos , Óperon Lac , Transformação Genética , Virulência/genética
6.
Biochimie ; 80(2): 99-108, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9587667

RESUMO

Lectins are present on the surface of many cells. Many lectins actively recycle from membrane to endosomes and efficiently take up glycoconjugates in a sugar-dependent manner. On this basis, glycoconjugates, specially those obtained by chemical means, are good candidates as carriers of drugs, oligonucleotides or genes. In this paper, we present a panel of methods suitable to transform unprotected reducing oligosaccharides into glycosynthons designed to be easily linked to therapeutic agents. All the glycosynthons presented here are glycosylamines or derivatives, mainly glyco-amino acids or glycopeptides. Glycosylamines are easy to obtain, but they are very labile in slightly acidic or neutral medium; they must be stabilized, by acylation for instance. The coupling efficiency of a reducing sugar with ammonia as well as an alkylamine or an arylamine is higher at high temperature, however, because of the Amadori rearrangement, special conditions have to be selected to prepare the expected glycosylamine derivative with a high yield. Glycosylamines are easily acylated by N-protected amino acids, or by halogeno acids which can then be transformed into amino acids. Alternatively, unprotected reducing oligosaccharides may very efficiently be transformed into N-glycosyl-amino acids and then protected by N-acylation. With a glutamyl derivative having both the alpha-amino and the gamma-carboxylic groups free, the coupling and the acylation, which is intramolecular, are roughly quantitative. N-oligosaccharyl-amino acid derivatives are interesting glycosynthons, because their sugar moiety bears the specificity towards membrane lectins while the amino acid part has the capacity to easily substitute a therapeutic agent.


Assuntos
Aminas/metabolismo , Aminoácidos/metabolismo , Glicoconjugados/metabolismo , Oligossacarídeos/metabolismo , Animais , Metabolismo dos Carboidratos , Glicosilação , Humanos , Oxirredução
7.
Ann Thorac Surg ; 65(5): 1291-5, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9594854

RESUMO

BACKGROUND: Control of hemorrhage in patients with active bleeding from rupture of the aortic arch is difficult, because of the location of the bleeding and the impossibility of cross-clamping the aorta without interfering with cerebral perfusion. A precise and swift plan of management helped us salvage some patients and prompted us to review our experience. METHODS: Six patients with active bleeding of the aortic arch in the mediastinum and pericardial cavity (5 patients) or left pleural cavity (1 patient), treated between 1992 and 1996, were reviewed. Bleeding was reduced by keeping the mediastinum under local tension (3 patients) or by applying compression on the bleeding site (2 patients), or both (1 patient) while circulatory support, retransfusion of aspirated blood, and hypothermia were established. The diseased aortic arch was replaced during deep hypothermic circulatory arrest, which ranged from 25 to 40 minutes. In 3 patients, the brain was further protected by retrograde (2 patients) or antegrade (1 patient) cerebral perfusion. RESULTS: Hemorrhage from the aortic arch was controlled in all patients. Two patients died postoperatively, one of respiratory failure and the other of abdominal sepsis. Recovery of neurologic function was assessed and complete in all patients. The 4 survivors are well 8 to 49 months after operation. CONCLUSIONS: An approach relying on local tamponade to reduce bleeding, rapid establishment of circulatory support and hypothermia, retransfusion of aspirated blood, and swift repair of the aortic arch under circulatory arrest allows salvage of patients with active bleeding from an aortic arch rupture.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Ruptura Aórtica/cirurgia , Hemorragia/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/cirurgia , Falso Aneurisma/cirurgia , Circulação Assistida , Transfusão de Sangue Autóloga , Ponte Cardiopulmonar , Causas de Morte , Circulação Cerebrovascular , Seguimentos , Parada Cardíaca Induzida , Hemorragia/cirurgia , Hemotórax/prevenção & controle , Hemotórax/cirurgia , Humanos , Hipotermia Induzida , Masculino , Mediastino , Pessoa de Meia-Idade , Exame Neurológico , Derrame Pericárdico/prevenção & controle , Derrame Pericárdico/cirurgia , Derrame Pleural/prevenção & controle , Derrame Pleural/cirurgia , Pressão , Insuficiência Respiratória/etiologia , Estudos Retrospectivos , Sepse/etiologia , Taxa de Sobrevida , Fatores de Tempo
8.
Ann Thorac Surg ; 70(4): 1219-23, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11081874

RESUMO

BACKGROUND: The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS: A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS: Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS: Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.


Assuntos
Endocardite Bacteriana/cirurgia , Implante de Prótese de Valva Cardíaca , Valvas Cardíacas/transplante , Infecções Relacionadas à Prótese/cirurgia , Adulto , Idoso , Valva Aórtica/cirurgia , Endocardite Bacteriana/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/cirurgia , Complicações Pós-Operatórias/mortalidade , Falha de Prótese , Infecções Relacionadas à Prótese/mortalidade , Reoperação , Taxa de Sobrevida , Transplante Homólogo
9.
Phytochemistry ; 49(6): 1537-48, 1998 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11711062

RESUMO

Expression of Agrobacterium tumefaciens virulence genes and transformation of dicots by this organism are dependent upon host plant phenolic compounds. Several alkylsyringamides have recently been shown to be powerful inducers of these vir-genes. These synthetic amides, and especially ethylsyringamide, are much stronger inducers than syringic acid. In this work, four alkylamides derived from ferulic or sinapic acids were synthesized by a dicyclohexylcarbodiimide method and tested for their potential to induce vir-gene expression on A. tumefaciens strains harbouring virB::lacZ or virE::lacZ fusion plasmids. Their effectiveness was compared to that of ethylsyringamide and tyraminylferulamide, a naturally occurring amide in plants. Whatever the amine moiety of the amide (ethylamine, propylamine, tyramine or beta-alanine ethyl ester) conjugation of the acid functional group clearly diminished the toxicity to the bacteria of the respective acid at high concentration and thereby increased the vir-inducing potential. However, none of the inducers tested exhibited higher activity than acetosyringone, the reference compound for vir-gene induction, with the exception of ethylsyringamide at concentrations above 1mM. When tested on Agrobacterium tumefaciens strain A348(pSM243cd), ethylferulamide and ethylsinapamide were more efficient than the corresponding phenolic acids but only above 100 microM.


Assuntos
Agrobacterium tumefaciens/efeitos dos fármacos , Agrobacterium tumefaciens/genética , Amidas/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Virulência/genética , Acetofenonas/farmacologia , Agrobacterium tumefaciens/patogenicidade , Amidas/síntese química , Amidas/química , Ácidos Cumáricos/farmacologia , Genes Bacterianos/genética , Extratos Vegetais/síntese química , Extratos Vegetais/farmacologia
10.
Ann Chir ; 52(4): 331-7, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9752465

RESUMO

AIM OF THE STUDY: To analyse the course of upper limb edema in patients with an arteriovenous fistula used for dialysis and to analyse the available therapeutic options. STUDY DESIGN: Retrospective study of patients with this type of edema, who were treated in our institution from 1992 to 1996. PATIENTS AND METHODS: Seven consecutive patients with an arterioveinous fistula treated for edema of the upper extremity, were reviewed. The fistula was created at the elbow in 6 patients and at the forearm in 1. The edema appeared immediately after operation in 4 patients and after a delay in 3 patients. Stenosis (3 patients) or occlusion (2 patients) of the subclavian vein was documented in 5 patients who were investigated by angiography. RESULTS: The edema regressed spontaneously in 4 patients because collaterals developed in 3 patients, and the fistula thrombosed in 1 patient. Surgical intervention allowed regression of the edema in the other 3 patients: excessive output of the fistula was reduced in 2 patients and an axillojugular bypass was performed in 1 patient. The fistula remained effective in 6 patients. Another fistula was performed on the contralateral arm in 1 patient. CONCLUSION: Non-operative management is recommended in patients who develop edema immediately after creation of the fistula, because spontaneous regression is likely. Measures aimed at reducing the output of the fistula or enhancing the venous capacities of the arm are required when edema appears at a later stage. The fistula can be saved in the majority of cases.


Assuntos
Braço , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Edema/etiologia , Veia Subclávia , Idoso , Circulação Colateral , Constrição Patológica/complicações , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/cirurgia , Feminino , Humanos , Masculino , Radiografia , Remissão Espontânea , Diálise Renal , Análise de Sobrevida
11.
Ann Endocrinol (Paris) ; 59(1): 23-6, 1998 Apr.
Artigo em Francês | MEDLINE | ID: mdl-9752395

RESUMO

Is surgery for primary hyperparathyroidism easier when methylene blue (MB) is given preoperatively? This retrospective study compares the durations of interventions for primary hyperparathyroidism carried out after i.v. MB administration to those when no MB was given. Over a period of 20 years (June 1976 to December 1996), 175 consecutive patients (56 men and 119 women, with ages ranging from 16 to 92, mean 59.6) were operated upon for primary hyperparathyrodism; 55 were operated before February 1986--the period when BM was introduced routinely, and 120 after. Thirty-two other patients were excluded from the study: 14 had had a previous cervicotomy and 18 another procedure in addition to the parathyroidectomy (usually on the thyroid gland), two conditions which prolonged the time devoted to parathyroid identification and excision. Preoperative calcemia averaged 2.97 mmol/L (2.34 to 4.59) and mean preoperative PTH was equal to 2.6 times the upper normal limit (0.5 to 24.1). Both groups were similar for as age, sex, preoperative calcium and PTH, and histologies. Methylene blue was administered intravenously (5 mg/kg diluted in 500 cc of 5% glucose) over a period of time of one hour starting two hours prior to surgery. All 175 procedures were performed by two surgeons and duration of surgery was recorded from the anesthesiologist's notes. There were 149 adenomas (85%), 24 hyperplasias (14%), a combination of both in two, and unspecified in two others. Except for a case of acute lower back pain synchronous to the injection of the dye (which was immediately stopped), MB was well tolerated. Mean duration for the 55 interventions performed without MB was 68 minutes (35 to 140, median 60), compared to 49 minutes for the 120 procedures carried out after MB had been given (20 to 155, median 45). Differences in operative, times were highly significant (p < 10(-6) and represented a gain of time of 27%. Surgery for primary hyperparathyroidism was significantly shorter when it was preceded by the administration of MB, a dye which facilitates the identification of pathologic parathyroid gland(s).


Assuntos
Hiperparatireoidismo/cirurgia , Azul de Metileno , Adenoma/diagnóstico , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hiperparatireoidismo/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/cirurgia , Paratireoidectomia , Estudos Retrospectivos
13.
Perfusion ; 23(4): 209-13, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19181752

RESUMO

The Admiral, a new microporous membrane oxygenator with a low surface area, decreased priming volume and two separate reservoirs, was tested in 30 adult patients. This study was undertaken to evaluate blood path resistance, gas exchange capabilities and blood trauma in clinical use, with and without shed blood separation. Patients were divided into 3 groups. Group 1 had valve surgery without separation of suction, Group 2 had coronary artery bypass grafting (CABG) with direct blood aspiration and Group 3 had coronary artery bypass grafting with shed blood separation. The suctioned, separated, cardiotomy blood in Group 3 was treated with an autotransfusion device at the end of bypass before being returned to the patient. Theoretical blood flow could be achieved in all cases without problem. The pressure drop through the oxygenator averaged 88 +/- 13 mmHg at 4 l/min and 109 +/- 12 mmHg at 5 l/min. O(2) transfer was 163 +/- 27 ml/min. Free plasma haemoglobin rose in all groups, but significantly less in group 3. Lactate dehydrogenase (LDH) rose significantly in Groups 1 and 2. Platelets decreased in all groups without significant differences. Clinical experience with this new oxygenator was safe, the reduced membrane surface did not impair gas exchange and blood trauma could be minimized easily by separating shed blood, using the second cardiotomy reservoir.


Assuntos
Ponte Cardiopulmonar/instrumentação , Ponte de Artéria Coronária/instrumentação , Oxigênio/sangue , Oxigenadores de Membrana , Sucção/instrumentação , Adulto , Idoso , Desenho de Equipamento , Hemoglobinas/análise , Humanos , L-Lactato Desidrogenase/sangue , Contagem de Leucócitos , Pressão
14.
Bioconjug Chem ; 3(1): 14-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1616944

RESUMO

An original procedure which preserves the structure of the sugar ring is described to link a plant hormone as N6-isopent-2-enyladenosine [( 9R]iP) onto a protein carrier to prepare a more specific immunogen. This cytokinin is bound to bovine serum albumin (BSA) and ovalbumin by a five-step procedure. These [9R]iP-protein conjugates have a maximal absorption at 269 nm and show molar ratios of hormone bound to proteins in the range of 12:1 and 18:1 for BSA and ovalbumin, respectively. Polyclonal antibodies were raised in rabbits against [9R]iP-BSA and were purified by affinity chromatography. Titers and specificity of the antisera and purified antibodies were determined by ELISA and RIA. These antibodies are highly specific for [9R]iP and do not cross-react with zeatin and ribosylzeatin. An immunoaffinity matrix was prepared with a capacity of 1 microgram of [9R]iP/mL of gel.


Assuntos
Anticorpos/imunologia , Citocininas/imunologia , Isopenteniladenosina/imunologia , Ovalbumina/imunologia , Soroalbumina Bovina/imunologia , Animais , Anticorpos/isolamento & purificação , Especificidade de Anticorpos , Cromatografia de Afinidade , Reações Cruzadas , Citocininas/química , Ensaio de Imunoadsorção Enzimática , Isopenteniladenosina/química , Ovalbumina/química , Coelhos , Soroalbumina Bovina/química , Espectrofotometria Ultravioleta
15.
Thorac Cardiovasc Surg ; 43(4): 220-2, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7502288

RESUMO

We report a patient with Marfan's syndrome and pectus excavatum who underwent open heart surgery with simultaneous correction of the sternal malformation. Permanent internal stabilization, achieved by bilateral overlapping of the bevelled ends of the lowest ribs and reinforced with sternal closure wires offered a maintained postoperative chest wall stability, avoided the potential postoperative complications of cardiac compression, and improved the aesthetic appearance of the anterior chest wall. The increased risk of bleeding due to extensive dissection was minimized by postponing the repair of pectus excavatum to when protamin is administered after termination of cardiopulmonary bypass.


Assuntos
Aneurisma Aórtico/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Tórax em Funil/cirurgia , Síndrome de Marfan/complicações , Aneurisma Aórtico/etiologia , Insuficiência da Valva Aórtica/etiologia , Fios Ortopédicos , Ponte Cardiopulmonar , Tórax em Funil/diagnóstico por imagem , Tórax em Funil/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
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