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The effects of cobalt deficiency on nodule formation and function in sweet lupin (Lupinus angustifolius L. cv. Unicrop) were studied in cobalt-deficient Lancelin sand in the glasshouse. Bacteroid densities in cobalt-deficient nodules were lower than in normal nodules. Recovery from cobalt deficiency in inoculated treatments was associated with increases in bacteroid density and cobalt accumulation in lateral nodules. Such changes did not occur in treatments infected with rhizobia from the soil. Acetylene-reducing activity of cobalt-deficient plants was not initiated until plants were nearly 6 weeks old, at which time cobalt-treated plants were at their peak of activity. Specific activities of cobalt-deficient nodules remained very low even when nitrogenase did develop. Their large mass of nodules allowed cobalt-deficient plants to reach 20 to 50% of the normal activity per plant, but specific activities were only 5 to 13% of peak activities in cobalt-treated nodules. Nodule bacteroid content and leghaemoglobin content were linearly related to cobalamin content, each with a single relationship. Plotting acetylene-reducing activity against cobalamin content or leghaemoglobin content generated two different linear response curves in each case; the slopes of the lines were different, depending on the presence or absence of cobalt. It is suggested that there may be a function in N2 fixation in legume nodules for a non-cobalamin form of cobalt. [ABSTRACT FROM AUTHOR]

Cobalt application markedly increased the growth of and nitrogen concentrations in tops of Lupinus angustifolius irrespective of inoculation with an effective strain of Rhizobium. Cobalt-deficient plants produced a greater weight of lateral nodules and total nodule weight than cobalt-adequate plants. Cobalt-sufficient plants produced more crown nodule weight than cobalt-deficient plants. Cobalt concentrations were higher in roots and nodules than in tops irrespective of cobalt application. In plant tops cobalt concentrations in young leaves were considerably lower than those in old leaves at both cobalt levels. Cobalt concentrations and contents increased in old leaves throughout the experiment. Under cobalt deficiency cobalt appeared to be preferentially distributed to nodules. Six weeks after sowing cobalt contents of nodules of cobalt-deficient plants were similar to those in whole tops. By contrast at this time cobalt contents of nodules of cobalt-adequate plants were only approximately one-third those of whole tops. [ABSTRACT FROM AUTHOR]

Objectives: Despite growing evidence that aortic valve repair improves long-term patient outcomes and quality of life, aortic valves are mostly replaced. We evaluate the effect of aortic valve repair versus replacement in patients with dystrophic aortic root aneurysm up to 4 years., Methods: The multicentric CAVIAAR (Conservation Aortique Valvulaire dans les Insuffisances Aortiques et les Anévrismes de la Racine aortique) prospective cohort study enrolled 261 patients: 130 underwent standardized aortic valve repair (REPAIR) consisting of remodelling root repair with expansible aortic ring annuloplasty, and 131 received mechanical composite valve and graft replacement (REPLACE). Primary outcome was a composite criterion of mortality, reoperation, thromboembolic or major bleeding events, endocarditis or operating site infections, pacemaker implantation and heart failure, analysed with propensity score-weighted Cox model analysis. Secondary outcomes included major adverse valve-related events and components of primary outcome., Results: The mean age was 56.1 years, and valve was bicuspid in 115 patients (44.7%). Up to 4 years, REPAIR did not significantly differ from REPLACE in terms of primary outcome [Hazard Ratio (HR) 0.66 (0.39; 1.12)] but showed significantly less valve-related deaths (HR 0.09 [0.02; 0.34]) and major bleeding events (HR 0.37 [0.16; 0.85]) without an increased risk of valve-related reoperation (HR 2.10 [0.64; 6.96]). When accounting for the occurrence of multiple events in a single patient, the REPAIR group had half the occurrence of major adverse valve-related events (HR 0.51 [0.31; 0.86])., Conclusions: Although the primary outcome did not significantly differ between the REPAIR and REPLACE groups, the trend is in favour of REPAIR by a significant reduction of valve-related deaths and major bleeding events. Long-term follow-up beyond 4 years is needed to confirm these findings., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Objective: To provide recommendations for enhanced recovery after cardiac surgery (ERACS) based on a multimodal perioperative medicine approach in adult cardiac surgery patients with the aim of improving patient satisfaction, reducing postoperative mortality and morbidity, and reducing the length of hospital stay., Design: A consensus committee of 20 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Society of Thoracic and Cardiovascular Surgery (Société française de chirurgie thoracique et cardio-vasculaire, SFCTCV) was convened. A formal conflict-of-interest policy was developed at the onset of the process and enforced throughout. The entire guideline process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide the assessment of the quality of evidence., Methods: Six fields were defined: (1) selection of the patient pathway and its information; (2) preoperative management and rehabilitation; (3) anaesthesia and analgesia for cardiac surgery; (4) surgical strategy for cardiac surgery and bypass management; (5) patient blood management; and (6) postoperative enhanced recovery. For each field, the objective of the recommendations was to answer questions formulated according to the PICO model (Population, Intervention, Comparison, Outcome). Based on these questions, an extensive bibliographic search was carried out and analyses were performed using the GRADE approach. The recommendations were formulated according to the GRADE methodology and then voted on by all the experts according to the GRADE grid method., Results: The SFAR/SFCTCV guideline panel provided 33 recommendations on the management of patients undergoing cardiac surgery under cardiopulmonary bypass or off-pump. After three rounds of voting and several amendments, a strong agreement was reached for the 33 recommendations. Of these recommendations, 10 have a high level of evidence (7 GRADE 1+ and 3 GRADE 1-); 19 have a moderate level of evidence (15 GRADE 2+ and 4 GRADE 2-); and 4 are expert opinions. Finally, no recommendations were provided for 3 questions., Conclusions: Strong agreement existed among the experts to provide recommendations to optimise the complete perioperative management of patients undergoing cardiac surgery., (Copyright © 2022 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Objective: The study objective was to compare the 30-day outcomes of a standardized aortic valve repair technique (REPAIR group) associating root remodeling with an expansible aortic ring annuloplasty versus mechanical composite valve and graft (CVG group) replacement in treating aortic root aneurysms., Methods: A total of 261 consecutive patients with aortic root aneurysm were enrolled in this multicentric prospective cohort (131 in the CVG group, 130 in the REPAIR group) in 20 centers. The main end point is a composite criterion including mortality; reoperation; thromboembolic, hemorrhagic, or infectious events; and heart failure. Secondary end points were major adverse valve-related events. Crude and propensity score adjusted estimates are provided., Results: The mean age was 56.1 years, and the valve was bicuspid in 115 patients (44.7%). The median (interquartile range) preoperative aortic insufficiency grade was 2.0 (1.0-3.0) in the REPAIR group and 3.0 (2.0-3.0) in the CVG group (P = .0002). Thirty-day mortality was 3.8% (n = 5) in both groups (P = 1.00). Despite a learning curve and longer crossclamp times for valve repair (147.7 vs 99.8 minutes, P < .0001), the 2 groups did not differ significantly for the main criterion (odds ratio, 1.31; 95% confidence interval, 0.72-2.40; P = .38) or 30-day mortality (odds ratio, 0.99; 95% confidence interval, 0.28-3053; P = .99), with a trend toward more frequent major adverse valve-related events in the CVG group (odds ratio, 2.52; 95% confidence interval, 0.86-7.40; P = .09). At discharge, 121 patients (96.8%) in the REPAIR group had grade 0 or 1 aortic insufficiency., Conclusions: A new standardized approach to valve repair, combining an expansible aortic annuloplasty ring with the remodeling technique, presented similar 30-day results to mechanical CVG with a trend toward reducing major adverse valve-related events. Analysis of late outcomes is in process for 3- and 10-year follow-ups., (Copyright © 2015. Published by Elsevier Inc.)

Dual antiplatelet therapy is commonly used in patients undergoing transcatheter aortic valve implantation (TAVI), but the optimal antiplatelet regimen is uncertain and remains to be determined. The objective of this study was to compare 2 strategies of antiplatelet therapy in patients undergoing TAVI. A strategy using monoantiplatelet therapy (group A, n = 164) was prospectively compared with a strategy using dual antiplatelet therapy (group B, n = 128) in 292 consecutive patients undergoing TAVI. The primary end point was a combination of mortality, major stroke, life-threatening bleeding (LTB), myocardial infarction, and major vascular complications at 30 days. All adverse events were adjudicated according to the Valve Academic Research Consortium. The primary end point occurred in 22 patients (13.4%) in the group A and in 30 patients (23.4%) in the group B (hazard ratio 0.51, 95% confidence interval 0.28 to 0.94, p = 0.026). LTB (3.7% vs 12.5%, p = 0.005) and major bleedings (2.4% vs 13.3%, p <0.0001) occurred less frequently in the group A, whereas the incidence of stroke (1.2% vs 4.7%, p = 0.14) and myocardial infarction (1.2% vs 0.8%, p = 1.0) was not significantly different between the 2 groups. The benefit of a strategy using mono versus dual antiplatelet therapy persisted after multivariate adjustment and propensity score analysis (hazard ratio 0.53, 95% confidence interval 0.28 to 0.95, p = 0.033). In conclusion, a strategy using mono versus dual antiplatelet therapy in patients undergoing TAVI reduces LTB and major bleedings without increasing the risk of stroke and myocardial infarction. The results of our study question the justification of dual antiplatelet therapy and require confirmation in a randomized trial., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: We suggest standardizing aortic valve repair using a physiologic approach by associating root remodeling with resuspension of the cusp effective height and external subvalvular aortic ring annuloplasty., Methods: A total of 187 patients underwent remodeling associated with subvalvular aortic ring annuloplasty (14 centers, 24 surgeons). Three strategies for cusp repair were evaluated: group 1, gross visual estimation (74 patients); group 2, alignment of cusp free edges (62 patients); and group 3, 2-step approach, alignment of the cusp free edges and effective height resuspension (51 patients). The composite outcome was defined as recurrence of aortic insufficiency of grade 2 or greater and/or reoperation., Results: The operative mortality rate was 3.2% (n = 6). Treatment of a cusp lesion was most frequently performed in group 3 (70.6% vs 20.3% in group 1 and 30.6% in group 2, P < .001). Nine patients required reoperation during a follow-up period of 24 months (range, 12-45), 6 patients in group 1 and 3 patients in group 2. At 1 year, no patients in group 3 presented with composite outcome events compared with 28.1% in group 1 and 15% in group 2 (P < .001). Residual aortic insufficiency and tricuspid anatomy were independent risk factors for the composite outcome in groups 1 and 2. The annulus diameter, the presence of Marfan syndrome, and cusp repair had no effect on aortic insufficiency recurrence or reoperation., Conclusions: A standardized and physiologic approach to aortic valve repair, considering both the aorta (root remodeling) and the valve (resuspension of the cusp effective height and subvalvular ring annuloplasty) improved the preliminary results and might affect their long-term durability. The ongoing Conservative Aortic Valve Surgery for Aortic Insufficiency and Aneurysm of the Aortic Root (CAVIAAR) trial will compare this strategy to mechanical valve replacement., (Copyright © 2010 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Background: The use of the internal thoracic artery for coronary artery bypass has improved the results of such surgery. However, bypass using only the internal thoracic arteries sometimes requires a T-graft. This purely internal thoracic artery T-graft technique has progressively become part of our surgical protocol for coronary artery bypass surgery., Aims: The aim of the study was to analyse the impact of this surgical technique on the degree and quality of coronary revascularization using early postoperative angiography., Methods: Between January 2004 and December 2006, 148 patients underwent coronary artery bypass surgery exclusively using both internal thoracic arteries in a T-graft configuration. Systematic postoperative angiography was offered to all 148 patients; it was accepted by 108 patients and refused by 40 patients., Results: There were no statistically significant differences between the two groups. In-patient mortality was 2.02% (n=3) for the whole population studied, and 1.49% (n=2) for the 134 patients who received only coronary artery bypass grafts. The revascularization rate was 89% and 3.46 coronary anastomoses were constructed per patient (range 2-6). Angiography was performed on 108 right internal thoracic artery to left internal thoracic artery anastomoses, 374 anastomoses of internal thoracic arteries to coronary arteries and 382 inter-anastomosis segments: 98% of the anastomoses and segments were patent., Conclusion: The exclusive recourse to the purely internal thoracic artery T-graft technique meant that it has been possible to dispense with other types of graft while achieving complete and effective revascularization of the coronary artery.

We describe a novel technique of using fluorescent silica nanoparticles (FSNPs) to detect over-expressed folate receptors, as typical for certain malignancies (metastatic adenocarcinoma, pituitary adenoma and others). Using Stöber's method with some modification, 135 nm size FSNPs were synthesized by a hydrolysis and co-condensation reaction of tetraethylorthosilicate (TEOS), fluorescein labeled (3-aminopropyl)triethoxysilane (APTS) and a water-dispersible silane reagent, (3-trihydroxysilyl)propyl methylphosphonate (THPMP) in the presence of ammonium hydroxide catalyst. Folic acid (folate) was covalently attached to the amine modified FSNPs by a carbodiimide coupling reaction. The characterization of folate-FSNPs was performed using a variety of spectroscopic (UV-VIS and fluorescence), microscopic (transmission electron microscopy, TEM) and light scattering techniques. Folate conjugated FSNPs were then targeted to human squamous cancer cells (SCC-9). Laser scanning confocal images successfully demonstrated the labeling of SCC-9 cells and the efficacy of FSNP based detection system.

The aim of this study was to report two cases of rupture of the right hemidiaphragm with intra-thoracic liver hernia, associated with a traumatic aortic disruption. These two lesions followed traffic accidents, and were both treated separately. Both patients had a long-term favourable progression. Association of these two lesions is particularly rare: fewer than 50 cases have been previously described in an extensive review of the literature. CT-scan seems to be particularly efficient in diagnosis, even if less efficient than other more specific explorations. The order of surgical management is guided by the physical examination, and especially by abdominal emergency.

Objectives: To define a link between the deletion genotype (DD) and vascular reactivity, we studied in vivo and in vitro phenylephrine (PE)-induced tone and the effect of angiotensin II (AII) at physiological (subthreshold) concentrations on PE-induced tone., Background: The deletion allele (D) of the angiotensin I-converting enzyme (ACE) has been associated with a higher circulating and cellular ACE activity and possibly with some cardiovascular diseases., Methods: During cardiac surgery PE-induced contraction was studied in patients with excessive hypotension. In parallel, excess material of internal mammary artery, isolated from patients operated for bypass surgery, was mounted in an organ chamber, in vitro, for isometric vascular wall force measurement., Results: In patients under extracorporeal circulation, PE (25 to 150 microg) induced higher contractions in patients with the DD genotype (e.g., with PE 75 microg: 20.3 +/- 2.9 vs. 11.5 +/- 2.5 mm Hg/ml per min, DD vs. II/ID, n = 15 vs. 30, p < 0.03). In the mammary artery, in vitro, contractions to PE (0.1 to 100 micromol/liter) or AII (1 or 100 nmol/liter) were not affected by the genotype. Angiotensin II (10 pmol/liter) significantly potentiated PE (1 micromol/liter)-induced contraction in both groups. Potentiation of PE-induced tone by AII was significantly higher in the DD than in the II/ID group., Conclusions: The DD genotype was associated with an increased reactivity to PE in vivo and potentiating effect of exogenous AII in vitro. The higher response to PE in vivo might reflect a higher potentiation by endogenous AII. These data should be considered to understand possible link(s) between cardiovascular disorders and the ACE gene polymorphism.

Objective: The diagnosis of perioperative myocardial infarction (PMI) after cardiac surgery remains an important issue. The present study was designed to determine the relevance of the measurement of serum cardiac troponin I (cTnI, a biochemical marker with high cardiospecificity. Therefore, cTnI was compared with creatine kinase-MB (CK-MB) mass and to the other classical signs of myocardial infarction after cardiac surgery., Design: A prospective study., Setting: A university hospital., Participants: Forty-one patients undergoing coronary artery bypass grafting (CABG) (n = 17) or valvular replacement (n = 24). These patients were separated into three groups according to postoperative complications: group 1, Q-wave PMI (n = 5); group 2, nonspecific changes (non-Q wave) on the electrocardiogram (ECG) and/or need of inotropic support (n = 12); group 3, no postoperative complication (n = 24)., Interventions: Postoperative follow-up consisted of serial determination of different biochemical markers (CK, CK-MB, cTnI), ECGs, and echocardiography. Blood samples were drawn before (H0) and 3 (H3), 12 (H12), 20 (H20), 24 (H24), and 48 (H48) hours after the onset of cardiopulmonary bypass (CPB)., Measurements and Main Results: In all patients in group 3, CK-MB and cTnI concentrations increased, and peaked at H12 after CPB (13.4 +/- 7.7 and 7.1 +/- 4.1 micrograms/L for CK-MB and cTnI, respectively). In group 1, cTnI concentrations were significantly higher than in group 3 from H12 until H48 (p < 0.002), peaked later (H24; 59.0 +/- 38.8 micrograms/L), and remained in plateau. In group 2, cTnI peak concentrations were significantly different than in groups 1 and 3 (26.2 +/- 14.8 micrograms/L) and occurred at H24 (as in patients with Q-wave PMI)., Conclusion: A cTnI concentration less than 15 micrograms/L (mean + 2 standard deviations [SDs] of peak cTnI in group 3) within 24 to 48 hours after cardiac surgery is highly suggestive of the absence of perioperative myocardial necrosis. Because of its higher cardiospecificity than CK-MB mass, and its prolonged release after myocardial necrosis, cTnI might be a useful tool in the diagnosis of PMI after cardiac surgery.

Background: It has been suggested that oxidant stress may play a role in the pathophysiology of heart failure. However, no definitive information is available because most previous approaches used to measure oxidant stress are nonspecific, inaccurate, and unreliable., Methods and Results: To evaluate oxidant stress in the heart, we measured pericardial fluid levels of 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha), a specific and quantitative marker of oxidant stress in vivo, in a series of 51 consecutive patients with ischemic and/or valvular heart disease referred for cardiac surgery. Pericardial levels of 8-iso-PGF2alpha were correlated with the functional severity of heart failure (NYHA classification) and with echocardiographic indices of ventricular dilatation measured by independent physicians. Pericardial levels of 8-iso-PGF2alpha were significantly increased in patients with symptomatic heart failure compared with asymptomatic patients and gradually increased with the functional severity of heart failure (P=.0003). In addition, pericardial levels of 8-iso-PGF2alpha were significantly correlated with left ventricular end-diastolic and end-systolic diameters (P=.008 and .026, respectively)., Conclusions: Pericardial levels of 8-iso-PGF2alpha increase with the functional severity of heart failure and are associated with ventricular dilatation. These data suggest an important role for in vivo oxidant stress on ventricular remodeling and the progression to heart failure.

For original ovoid shaped artificial ventricles, a biomechanical double sac consisting of a biological sac (porcine pericardium) as the blood contact interface and a synthetic sac (Pebax 3533) as the mechanical support to assume systolic-diastolic dynamic constraints was conceived. The volumetric and mechanical properties were assessed with a three-dimensional modeling of Pebax sacs and computerized simulations of their systolic distortions for both right and left ventricular configurations. The stresses and strains of these sacs were represented as quantitative mappings for a maximum end-systolic state and were below the respective threshold values above which the Pebax material is jeopardized for permanent structure impairment. After fatigue tests applied on Pebax strips under the alleged working conditions of Pebax sacs, the material structure was unchanged and maintained its intrinsic mechanical properties. The theoretical maximum stroke volumes were 74.4 cm3 and 62.4 cm3 for the left and right ventricular configurations, respectively. With these mechanical and volumetric features, the biomechanical double sac concept was considered valid and could be provided for a consequent specific total artificial heart.

Objective: To assess blood polymorphonuclear neutrophil (PMN) activation status during normothermic cardiopulmonary bypass (CPB), the expression of the PMN adhesion molecule CD11b/CD18 was measured. Basal state as well as ex vivo capacity of PMN to be stimulated by a bacterial peptide (FMLP) were investigated. Because interleukin-8 (IL-8) is known to induce CD11b/CD18 expression in vitro in PMN, IL-8 plasma levels were concomitantly measured., Design: Prospective study., Setting: University hospital., Participants: Thirteen patients scheduled for cardiac surgery., Interventions: Systemic arterial and pulmonary arterial blood samples were withdrawn at the same moment during the first 4 hours after the onset of CPB., Measurements and Main Results: Twenty minutes after the onset of CPB, basal expression of PMN CD11b/CD18 was upregulated, whereas IL-8 plasma levels remained unchanged. The increase in PMN CD11b expression was maintained until the fourth hour after the onset of CPB. At this time, elevation of IL-8 plasma levels was maximal. No differences were found between pulmonary and systemic arterial IL-8 plasma levels, even after aortic unclamping. The capacity of PMN to be stimulated ex vivo by FMLP remained normal., Conclusions: Normothermic CPB induced a fast increase in CD11b expression, which appeared to be similar to that observed during hypothermia. IL-8 was probably not related to the very early CD11b upregulation, but could be involved in pulmonary PMN sequestration during pulmonary reperfusion and contribute to the maintained expression of PMN CD11b. Although partially activated, PMNs maintain a normal capacity to respond to a further FMLP stimulation and thus to bacterial infection.