Background: Transcatheter aortic valve implantation (TAVI) has emerged as an effective and safe treatment for patients with symptomatic aortic stenosis. The indication to TAVI should be agreed upon by a Heart Team, and the procedure should be performed in centers with on-site cardiac surgery. However, TAVI complications requiring emergent cardiac surgery (ECS) have become very rare.
View Article and Find Full Text PDFBackground: The effectiveness of complete revascularization is well established in patients with ST-segment elevation myocardial infarction (STEMI), but it is less investigated in those with non-ST-segment elevation myocardial infarction (NSTEMI).
Objectives: This study aimed to assess whether complete revascularization, compared with culprit-only revascularization, was associated with consistent outcomes in older patients with STEMI and NSTEMI.
Methods: In the FIRE (Functional Assessment in Elderly MI Patients with Multivessel Disease) trial, 1,445 older patients with myocardial infarction (MI) were randomized to culprit-only or physiology-guided complete revascularization, stratified by STEMI (n = 256 culprit-only vs n = 253 complete) and NSTEMI (n = 469 culprit-only vs n = 467 complete).
Background: There is little data on the outcome of balloon aortic valvuloplasty (BAV) in relation to valve dimensions and calcification patterns. The procedure is not standardized, particularly the choice of balloon size.
Methods: This retrospective multicenter study focused on BAV efficacy and safety by analyzing the relationship between balloon size, annulus geometry (i.
Background: The FIRE trial (Functional Assessment in Elderly Myocardial Infarction Patients With Multivessel Disease) enrolled 1445 older (aged ≥75 years) patients with myocardial infarction and multivessel disease in Italy, Spain, and Poland. Patients were randomized to physiology-guided complete revascularization or treatment of the only culprit lesion. Physiology-guided complete revascularization significantly reduced ischemic adverse events at 1 year.
View Article and Find Full Text PDFBackground: The role of quantitative flow ratio (QFR) in the treatment of nonculprit vessels of patients with myocardial infarction (MI) is a topic of ongoing discussion.
Objectives: This study aimed to investigate the predictive capability of QFR for adverse events and its noninferiority compared to wire-based functional assessment in nonculprit vessels of MI patients.
Methods: The FIRE (Functional Assessment in Elderly MI Patients With Multivessel Disease) trial randomized 1,445 older MI patients to culprit-only (n = 725) or physiology-guided complete revascularization (n = 720).
Aims: The present analysis from the Functional Assessment in Elderly Myocardial Infarction Patients with Multivessel Disease (FIRE) trial aims to explore the significance of pre-admission physical activity and assess whether the benefits of physiology-guided complete revascularization apply consistently to sedentary and active older patients.
Methods And Results: Patients aged 75 years or more with myocardial infarction (MI) and multivessel disease were randomized to receive physiology-guided complete revascularization or culprit-only strategy. The primary outcome was a composite of death, MI, stroke, or any revascularization within a year.
This work showcases the performance of [NiFeSe] hydrogenase from Desulfomicrobium baculatum for solar-driven hydrogen generation in a variety of organic-based deep eutectic solvents. Despite its well-known sensitivity towards air and organic solvents, the hydrogenase shows remarkable performance under an aerobic atmosphere in these solvents when paired with a TiO photocatalyst. Tuning the water content further increases hydrogen evolution activity to a TOF of 60±3 s and quantum yield to 2.
View Article and Find Full Text PDFAn original 1-acetato-4-(1-pyrenyl)-1,4,7-triazacyclononane (AcPyTACN) was synthesized for the immobilization of a His-tagged recombinant CODH from Rhodospirillum rubrum (RrCODH) on carbon-nanotube electrodes. The strong binding of the enzyme at the Ni-AcPyTACN complex affords a high current density of 4.9 mA cm towards electroenzymatic CO reduction and a high stability of more than 6×10 TON when integrated on a gas-diffusion bioelectrode.
View Article and Find Full Text PDFSome carboxydotrophs like Rhodospirillum rubrum are able to grow with CO as their sole source of energy using a Carbone monoxide dehydrogenase (CODH) and an Energy conserving hydrogenase (ECH) to perform anaerobically the so called water-gas shift reaction (WGSR) (CO + HO → CO + H). Several studies have focused at the biochemical and biophysical level on this enzymatic system and a few OMICS studies on CO metabolism. Knowing that CO is toxic in particular due to its binding to heme iron atoms, and is even considered as a potential antibacterial agent, we decided to use a proteomic approach in order to analyze R.
View Article and Find Full Text PDFNickel insertion into nickel-dependent carbon monoxide dehydrogenase (CODH) represents a key step in the enzyme activation. This is the last step of the biosynthesis of the active site, which contains an atypical heteronuclear NiFeS cluster known as the C-cluster. The enzyme maturation is performed by three accessory proteins, namely CooC, CooT and CooJ.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
June 2021
An artificial amyloid-based redox hydrogel was designed for mediating electron transfer between a [NiFeSe] hydrogenase and an electrode. Starting from a mutated prion-forming domain of fungal protein HET-s, a hybrid redox protein containing a single benzyl methyl viologen moiety was synthesized. This protein was able to self-assemble into structurally homogenous nanofibrils.
View Article and Find Full Text PDFPerforming a heterogeneous catalysis with proteins is still a challenge. Herein, we demonstrate the importance of cross-linked crystals for sulfoxide oxidation by an artificial enzyme. The biohybrid consists of the insertion of an iron complex into a NikA protein crystal.
View Article and Find Full Text PDFNickel enzymes, present in archaea, bacteria, plants, and primitive eukaryotes are divided into redox and nonredox enzymes and play key functions in diverse metabolic processes, such as energy metabolism and virulence. They catalyze various reactions by using active sites of diverse complexities, such as mononuclear nickel in Ni-superoxide dismutase, glyoxylase I and acireductone dioxygenase, dinuclear nickel in urease, heteronuclear metalloclusters in [NiFe]-carbon monoxide dehydrogenase, acetyl-CoA decarbonylase/synthase and [NiFe]-hydrogenase, and even more complex cofactors in methyl-CoM reductase and lactate racemase. The presence of metalloenzymes in a cell necessitates a tight regulation of metal homeostasis, in order to maintain the appropriate intracellular concentration of nickel while avoiding its toxicity.
View Article and Find Full Text PDFIn Rhodospirillum rubrum, the maturation of carbon monoxide dehydrogenase (CODH) requires three nickel chaperones, namely RrCooC, RrCooT and RrCooJ. Recently, the biophysical characterisation of the RrCooT homodimer and the X-ray structure of its apo form revealed the existence of a solvent-exposed Ni -binding site at the dimer interface, involving the strictly conserved Cys2. Here, a multifaceted approach that used NMR and X-ray absorption spectroscopies, complemented with structural bio-modelling methodologies, was used to characterise the binding mode of Ni in RrCooT.
View Article and Find Full Text PDFActivation of nickel enzymes requires specific accessory proteins organized in multiprotein complexes controlling metal transfer to the active site. Histidine-rich clusters are generally present in at least one of the metallochaperones involved in nickel delivery. The maturation of carbon monoxide dehydrogenase in the proteobacterium requires three accessory proteins, CooC, CooT, and CooJ, dedicated to nickel insertion into the active site, a distorted [NiFeS] cluster coordinated to an iron site.
View Article and Find Full Text PDFBackground And Aims: Excess body weight (EBW) is the most prevalent nutritional disorder among adolescents worldwide. Identifying determinants of EBW may help find new intervention strategies. Behavioral, socio-economic, educational and demographic correlates of EBW were examined in a population of Italian adolescents, separately for males and females.
View Article and Find Full Text PDFis a Gram-negative bacterium causing tularaemia. Classified as possible bioterrorism agent, it may be transmitted to humans via animal infection or inhalation leading to severe pneumonia. Its virulence is related to iron homeostasis involving siderophore biosynthesis directly controlled at the transcription level by the ferric uptake regulator Fur, as presented here together with the first crystal structure of the tetrameric Fur in the presence of its physiological cofactor, Fe.
View Article and Find Full Text PDFCarboxydothermus hydrogenoformans is a model microorganism for the study of [NiFe]-CODH, a key enzyme of carbon cycle in anaerobic microorganisms. The enzyme possesses a unique active site (C-cluster), constituted of a distorted [NiFeS] cubane linked to a mononuclear Fe(II) center. Both the biogenesis of the C-cluster and the activation of CODH by nickel insertion remain unclear.
View Article and Find Full Text PDFDesigning systems that merge the advantages of heterogeneous catalysis, enzymology, and molecular catalysis represents the next major goal for sustainable chemistry. Cross-linked enzyme crystals display most of these essential assets (well-designed mesoporous support, protein selectivity, and molecular recognition of substrates). Nevertheless, a lack of reaction diversity, particularly in the field of oxidation, remains a constraint for their increased use in the field.
View Article and Find Full Text PDFThioredoxin reductase (TR) regulates the intracellular redox environment by reducing thioredoxin (Trx). In anaerobes, recent findings indicate that the Trx redox network is implicated in the global redox regulation of metabolism but also actively participates in protecting cells against O. In the anaerobe Hildenborough (H), there is an intriguing redundancy of the Trx system which includes a classical system using NADPH as electron source, a non-canonical system using NADH and an isolated TR (DvTRi).
View Article and Find Full Text PDFIn Rhodospirillum rubrum, maturation of Carbon Monoxide Dehydrogenase (CODH) requires three accessory proteins, CooC, CooT and CooJ, dedicated to nickel insertion into the active site, which is constituted by a distorted [NiFeS] cubane coordinated with a mononuclear Fe site. CooC is an ATPase proposed to provide the energy required for the maturation process, while CooJ is described as a metallochaperone with 16 histidines and 2 cysteines at the C-terminus, likely involved in metal binding and/or storage. Prior to the present study, no information was available on CooT at the molecular level.
View Article and Find Full Text PDFArtificial enzymes are required to catalyse non-natural reactions. Here, a hybrid catalyst was developed by embedding a novel Ru complex in the transport protein NikA. The protein scaffold activates the bound Ru complex to produce a catalyst with high regio- and stereo-selectivity.
View Article and Find Full Text PDFBackground: Patients with failed bioprostheses are an increasing population at high risk for redo surgery. Valve-in-valve transcatheter aortic valve implantation is a promising alternative but a limited number of first-generation devices have proven efficacy in all cases.
Methods: Patients with degenerated bioprostheses at high risk for redo surgery were included in the registry after being assigned to valve-in-valve intervention by a local heart team.