Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Perfusion ; 38(7): 1360-1383, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-35961654

RESUMO

The landmark 2016 Minimal Invasive Extracorporeal Technologies International Society (MiECTiS) position paper promoted the creation of a common language between cardiac surgeons, anesthesiologists and perfusionists which led to the development of a stable framework that paved the way for the advancement of minimal invasive perfusion and related technologies. The current expert consensus document offers an update in areas for which new evidence has emerged. In the light of published literature, modular minimal invasive extracorporeal circulation (MiECC) has been established as a safe and effective perfusion technique that increases biocompatibility and ultimately ensures perfusion safety in all adult cardiac surgical procedures, including re-operations, aortic arch and emergency surgery. Moreover, it was recognized that incorporation of MiECC strategies advances minimal invasive cardiac surgery (MICS) by combining reduced surgical trauma with minimal physiologic derangements. Minimal Invasive Extracorporeal Technologies International Society considers MiECC as a physiologically-based multidisciplinary strategy for performing cardiac surgery that is associated with significant evidence-based clinical benefit that has accrued over the years. Widespread adoption of this technology is thus strongly advocated to obtain additional healthcare benefit while advancing patient care.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Adulto , Humanos , Procedimentos Cirúrgicos Cardíacos/métodos , Circulação Extracorpórea/métodos , Perfusão , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Coração
2.
Chemphyschem ; 22(24): 2550-2561, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34609055

RESUMO

Considering the vast importance of peptide and protein interactions with inorganic surfaces, probing hydrogen bonding during their adsorption on metal oxide surfaces is a relevant task that could shed light on the essential features of their interplay. This work is devoted to studying the dipeptides' adsorption on anatase nanoparticles (ANs) in light and heavy water to reveal differences arising upon the change of the major hydrogen bonding carrier. Thermodynamic study of six native dipeptides' adsorption on ANs in both media shows a strong influence of the solvent on the Gibbs free energy and the effect of side-chain mobile protons on the entropy of the process. The adsorption is endothermic irrespective of the medium and is entropy-driven. Computer simulations of peptide adsorption in both media shows similarity in binding via an amino group and demonstrates structural features of protonated and deuterated peptides in obtained complexes. Calculated peptide- anatase nanoparticle (AN) descriptors indicate surface oxygens as points of peptide-nanoparticle contacts.

3.
Molecules ; 26(16)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34443520

RESUMO

This paper presents an improved synthesis of 4,7-dibromobenzo[d][1,2,3]thiadiazole from commercially available reagents. According to quantum-mechanical calculations, benzo[d][1,2,3]thiadiazole (isoBTD) has higher values of ELUMO and energy band gap (Eg), which indicates high electron conductivity, occurring due to the high stability of the molecule in the excited state. We studied the cross-coupling reactions of this dibromide and found that the highest yields of π-spacer-acceptor-π-spacer type compounds were obtained by means of the Stille reaction. Therefore, 6 new structures of this type have been synthesized. A detailed study of the optical and electrochemical properties of the obtained π-spacer-acceptor-π-spacer type compounds in comparison with isomeric structures based on benzo[c][1,2,5]thiadiazole (BTD) showed a red shift of absorption maxima with lower absorptive and luminescent capacity. However, the addition of the 2,2'-bithiophene fragment as a π-spacer resulted in an unexpected increase of the extinction coefficient in the UV/vis spectra along with a blue shift of both absorption maxima for the isoBTD-based compound as compared to the BTD-based compound. Thus, a thorough selection of components in the designing of appropriate compounds with benzo[d][1,2,3]thiadiazole as an internal acceptor can lead to promising photovoltaic materials.

4.
J Interv Cardiol ; 2020: 5458064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31969796

RESUMO

AIM: Optimal revascularization strategy in multivessel (MV) coronary artery disease (CAD) eligible for percutaneous management (PCI) and surgery remains unresolved. We evaluated, in a randomized clinical trial, residual myocardial ischemia (RI) and clinical outcomes of MV-CAD revascularization using coronary artery bypass grafting (CABG), hybrid coronary revascularization (HCR), or MV-PCI. METHODS: Consecutive MV-CAD patients (n = 155) were randomized (1 : 1 : 1) to conventional CABG (LIMA-LAD plus venous grafts) or HCR (MIDCAB LIMA-LAD followed by PCI for remaining vessels) or MV-PCI (everolimus-eluting CoCr stents) under Heart Team agreement on equal technical and clinical feasibility of each strategy. SPECT at 12 months (primary endpoint of RI that the trial was powered for; a measure of revascularization midterm efficacy and an independent predictor of long-term prognosis) preceded routine angiographic control. RESULTS: Data are given, respectively, for the CABG, HCR, and MV-PCI arms. Incomplete revascularization rate was 8.0% vs. 7.7% vs. 5.7% (p=0.71). Hospital stay was 13.8 vs. 13.5 vs. 4.5 days (p < 0.001), and sick-leave duration was 23 vs. 16 vs. 8 weeks (p < 0.001). At 12 months, RI was 5 (2, 9)% vs. 5 (3, 7)% vs. 6 (3, 10)% (median; Q1, Q3) with noninferiority p values of 0.0006 (HCR vs. CABG) and 0.016 (MV-PCI vs. CABG). Rates of angiographic graft stenosis/occlusion or in-segment restenosis were 20.4% vs. 8.2% vs. 5.9% (p=0.05). Clinical target vessel/graft failure occurred in 12.0% vs. 11.5% vs. 11.3% (p=0.62). Major adverse cardiac and cerebral event (MACCE) rate was similar (12% vs. 13.4% vs. 13.2%; p=0.83). CONCLUSION: In this first randomized controlled study comparing CABG, HCR, and MV-PCI, residual myocardial ischemia and MACCE were similar at 12 months. There was no midterm indication of any added value of HCR. Hospital stay and sick-leave duration were shortest with MV-PCI. While longer-term follow-up is warranted, these findings may impact patient and physician choices and healthcare resources utilization. This trial is registered with NCT01699048.


Assuntos
Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Intervenção Coronária Percutânea , Complicações Pós-Operatórias , Idoso , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/métodos , Stents Farmacológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia
5.
Molecules ; 25(17)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824981

RESUMO

A new synthetic pathway to four substituted imidazoles from readily available 2-((4-aryl(thienyl)-5H-1,2,3-dithiazol-5-ylidene)amino)phenols has been developed. Benzo[d]oxazol-2-yl(aryl(thienyl))methanimines were proved as key intermediates in their synthesis. The formation of an imidazole ring from two methanimine derivatives likely includes the opening of one benzoxazole ring followed by ring closure by intermolecular nucleophilic attack of the N-methanimine atom to a carbon atom of another methanimine.


Assuntos
Benzoxazóis/química , Imidazóis/química , Iminas/química , Fenóis/síntese química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
6.
Molecules ; 24(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013657

RESUMO

Four new D-A-π-A metal-free organic sensitizers for dye-sensitized solar cells (DSSCs), with [1,2,5]thiadiazolo[3 ,4-d]pyridazine as internal acceptor, thiophene unit as π-spacer and cyanoacrylate as anchoring electron acceptor, have been synthesized. The donor moiety was introduced into [1,2,5]thiadiazolo[3,4-d]pyridazine by nucleophilic aromatic substitution and Suzuki cross-coupling reactions, allowing design of D-A-π-A sensitizers with the donor attached to the internal heterocyclic acceptor not only by the carbon atom, as it is in a majority of DSSCs, but by the nitrogen atom also. Although low values of power conversion efficiency (PCE) were found, a few important consequences were identified: (i) poor PCE data can be attributed to high electron deficiency of the internal [1,2,5]thiadiazolo[3,4-d]pyridazine acceptor due to lower light harvesting by the dye; (ii) the manner in which the donor was attached to the internal acceptor (by carbon or nitrogen) did not play an essential role in the photovoltaic properties of the dyes; (iii) dyes based on the novel donor 2,3,4,4a,9,9a-hexahydro-1H-1,4-methanocarbazolyl and 9-(p-tolyl)-2,3,4,4a,9,9a-hexahydro-1H- carbazole moieties showed similar photovoltaic properties to dyes based on the well-known 4-(p-tolyl)-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indolyl building block, which opens the door for further optimization potential of new dye families.


Assuntos
Corantes/química , Fontes de Energia Elétrica , Piridazinas/química , Energia Solar
7.
Molecules ; 23(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304797

RESUMO

A safe and efficient synthesis of 4,7-dibromo[1,2,5]thiadiazolo[3,4-d]pyridazine from the commercial diaminomaleonitrile is reported. Conditions for selective aromatic nucleophilic substitution of one or two bromine atoms by oxygen and nitrogen nucleophiles are found, whereas thiols formed the bis-derivatives only. Buchwald-Hartwig or Ullmann techniques are successful for incorporation of a weak nitrogen base, such as carbazole, into the [1,2,5]thiadiazolo[3,4-d]pyridazine core. The formation of rather stable S…η²-(N=N) bound chains in 4,7-bis(alkylthio)-[1,2,5]thiadiazolo[3,4-d]pyridines makes these compounds promising for the design of liquid crystals.


Assuntos
Piridazinas/química , Tiadiazóis/química , Modelos Moleculares , Nitrogênio/química , Piridazinas/síntese química , Compostos de Sulfidrila/química
8.
Molecules ; 23(6)2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29795048

RESUMO

Thermolysis of 4,4'-dichloro-, 4,4'-diaryl-, and 4,4'-di(thien-2-yl)-5,5'-bi(1,2,3-dithiazol-ylidenes) affords the respective 3,6-dichloro-, 3,6-diaryl- and 3,6-di(thien-2-yl)isothiazolo[5,4-d]-isothiazoles in low to high yields. The transformation of the 4,4'-diaryl- and 4,4'-di(thien-2-yl)-5,5'-bi(1,2,3-dithiazolylidenes) occurs at lower temperatures in the presence of the thiophiles triphenylphosphine or tetraethylammonium iodide. Optimized reaction conditions and a mechanistic rationale for the thiophile-mediated ring transformation are presented.


Assuntos
Tiazóis/síntese química , Modelos Moleculares , Estrutura Molecular , Temperatura , Tiazóis/química
9.
Kardiologiia ; 58(4): 96-100, 2018 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-30704391

RESUMO

We present here a case of successful staged treatment of a patient with para-aortic abscess that arose 5 years after thoracic endovascular aortic repair because of thoracic aortic aneurysm. After stabilization of the patient's condition by intensive antibiotic therapy we performed left-subclavian extra-thoracic debranching as the first stage of the surgical treatment. In 2 weeks via median sternotomy and on-pump we removed the infected endograft and performed extraanatomical ascending-to-descending aortic bypass with good postoperative result.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Aorta Torácica , Prótese Vascular , Humanos , Stents , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
Chemistry ; 20(26): 8189-98, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24824842

RESUMO

Chemical ligations to form native peptides from N→N acyl migrations in Trp-containing peptides via 10- to 18-membered cyclic transition states are described. In this study, a statistical, predictive model that uses an extensive synthetic and computational approach to rationalize the chemical ligation is reported. N→N acyl migrations that form longer native peptides without the use of Cys/Ser/Tyr residues or an auxiliary group at the ligation site were achieved. The feasibility of these traceless chemical ligations is supported by the N-C bond distance in N-acyl isopeptides. The intramolecular nature of the chemical ligations is justified by using competitive experiments and theoretical calculations.


Assuntos
Peptídeos/química , Peptídeos/síntese química , Triptofano/química , Acilação , Ligadura , Estrutura Molecular , Estereoisomerismo , Triptofano/análogos & derivados
11.
J Org Chem ; 78(15): 7455-61, 2013 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-23758522

RESUMO

Efficient syntheses of O-acyl Tyr-peptides allow chemical long-range ligation (O-acyl to N-acyl transfer) via each of 12- to 19-membered cyclic transition states. The results represent the first examples of successful isopeptide ligations starting from O-acyl Tyr-peptides.


Assuntos
Peptídeos/síntese química , Tirosina/química , Estrutura Molecular , Peptídeos/química
12.
Org Biomol Chem ; 11(10): 1594-7, 2013 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-23361377

RESUMO

N-Acyl tryptophan isopeptides undergo acyl transfer in chemical ligations via 7-, 10-, 11- and 12-membered cyclic transition states to yield natural peptides, representing the first examples of successful isopeptide ligations from N-acyl tryptophan units.


Assuntos
Peptídeos/síntese química , Triptofano/química , Acilação , Estrutura Molecular , Peptídeos/química , Estereoisomerismo , Triptofano/análogos & derivados
13.
J Med Chem ; 61(16): 7116-7130, 2018 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-30052441

RESUMO

Sirtuin 1 (SIRT1) is a class III histone deacetylase that plays significant roles in the regulation of lifespan, metabolism, memory, and circadian rhythms and in the mechanisms of many diseases. However, methods of monitoring the pharmacodynamics of SIRT1-targeted drugs are limited to blood sampling because of the invasive nature of biopsies. For the noninvasive monitoring of the spatial and temporal dynamics of SIRT1 expression-activity in vivo by PET-CT-MRI, we developed a novel substrate-type radiotracer, [18F]-2-fluorobenzoylaminohexanoicanilide (2-[18F]BzAHA). PET-CT-MRI studies in rats demonstrated increased accumulation of 2-[18F]BzAHA-derived radioactivity in the hypothalamus, hippocampus, nucleus accumbens, and locus coeruleus, consistent with autoradiographic and immunofluorescent (IMF) analyses of brain-tissue sections. Pretreatment with the SIRT1 specific inhibitor, EX-527 (5 mg/kg, ip), resulted in about a 20% reduction of 2-[18F]BzAHA-derived-radioactivity accumulation in these structures. In vivo imaging of SIRT1 expression-activity should facilitate studies that improve the understanding of SIRT1-mediated regulation in the brain and aid in the development and clinical translation of SIRT1-targeted therapies.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/química , Sirtuína 1/metabolismo , Animais , Autorradiografia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Carbazóis/farmacologia , Radioisótopos de Flúor , Espectroscopia de Ressonância Magnética , Masculino , Microscopia de Fluorescência , Imagem Molecular/métodos , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Relação Estrutura-Atividade
14.
Mol Imaging Biol ; 20(4): 594-604, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29423902

RESUMO

PURPOSE: The purpose of this study was to develop a SIRT2-specific substrate-type radiotracer for non-invasive PET imaging of epigenetic regulatory processes mediated by SIRT2 in normal and disease tissues. PROCEDURES: A library of compounds containing tert-butyloxycarbonyl-lysine-aminomethylcoumarin backbone was derivatized with fluoroalkyl chains 3-16 carbons in length. SIRT2 most efficiently cleaved the myristoyl, followed by 12-fluorododecanoic and 10-fluorodecanoic groups (Kcat/Km 716.5 ± 72.8, 615.4 ± 50.5, 269.5 ± 52.1/s mol, respectively). Radiosynthesis of 12- [18F]fluorododecanoic aminohexanoicanilide (12-[18F]DDAHA) was achieved by nucleophilic radiofluorination of 12-iododecanoic-AHA precursor. RESULTS: A significantly higher accumulation of 12-[18F]DDAHA was observed in MCF-7 and MDA-MB-435 cells in vitro as compared to U87, MiaPaCa, and MCF10A, which was consistent with levels of SIRT2 expression. Initial in vivo studies using 12-[18F]DDAHA conducted in a 9L glioma-bearing rats were discouraging, due to rapid defluorination of this radiotracer upon intravenous administration, as evidenced by significant accumulation of F-18 radioactivity in the skull and other bones, which confounded the interpretation of images of radiotracer accumulation within the tumor and other regions of the brain. CONCLUSIONS: The next generation of SIRT2-specific radiotracers resistant to systemic defluorination should be developed using alternative sites of radiofluorination on the aliphatic chain of DDAHA. A SIRT2-selective radiotracer may provide information about SIRT2 expression and activity in tumors and normal organs and tissues, which may help to better understand the roles of SIRT2 in different diseases.


Assuntos
Imagem Molecular , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/química , Sirtuína 2/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Linhagem Celular Tumoral , Simulação por Computador , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Cinética , Lisina/química , Imageamento por Ressonância Magnética , Compostos Radiofarmacêuticos/síntese química , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X
15.
J Mol Graph Model ; 71: 211-217, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27939933

RESUMO

Galectin-3 (Gal-3) is a carbohydrate binding protein that is overexpressed in several types of cancers, including pancreatic cancer, which makes it a good target for both imaging and therapeutic drug design. A ligand library specialized for 18F positron emission tomography (PET) has been investigated with molecular dynamics (MD) and free energy methods to determine the relative binding energies of various potential ligands. Our results suggest that traditional docking methods can give good results when complemented by molecular dynamics and free energy methods for these types of ligands. Available experimental binding affinities for a small number of the tested compounds show very good agreement with the calculated energies and provide the rational approach for design of Gal-3 ligands with even higher affinity.


Assuntos
Carboidratos/química , Galectina 3/química , Termodinâmica , Sítios de Ligação , Proteínas Sanguíneas , Galectinas , Humanos , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Tomografia por Emissão de Pósitrons , Ligação Proteica , Conformação Proteica
16.
Heart Lung ; 44(4): 309-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25913808

RESUMO

OBJECTIVE: We report our initial experience with extracorporeal membrane oxygenation (ECMO) use in elective high-risk complex percutaneous coronary intervention (PCI). BACKGROUND: ECMO has been employed as hemodynamic support in patients with cardiac arrest and hemodynamic shock. METHODS: We performed a single-center prospectical study, enrolling all patients at very high-risk for coronary artery bypass grafting (CABG). Major adverse cardiac and cerebrovascular events (MACCE) were defined as a composite of death, acute myocardial infarction (MI), stroke and further need for revascularization. RESULTS: Twelve patients underwent elective high-risk PCI with ECMO support (mean age = 63.5 ± 8.7 years). The mean SYNTAX score was 30.1 ± 10.1. All PCI procedures were successful and no in-hospital MACCE was observed. At 6-months, neither death nor MI was noticed. Two patients (17%) required further revascularization, and one patient required chronic hemodialysis. CONCLUSIONS: Elective high-risk PCI supported by ECMO is a viable alternative for patients who are at very high risk for CABG.


Assuntos
Doença da Artéria Coronariana/cirurgia , Oxigenação por Membrana Extracorpórea/métodos , Intervenção Coronária Percutânea/métodos , Idoso , Ponte de Artéria Coronária/métodos , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Parada Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/cirurgia , Revascularização Miocárdica/métodos , Estudos Prospectivos , Reoperação , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
17.
PLoS One ; 10(4): e0122601, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25856389

RESUMO

Epigenetic mechanisms of gene regulation in context of cardiovascular diseases are of considerable interest. So far, our current knowledge of the DNA methylation profiles for atherosclerosis affected and healthy human vascular tissues is still limited. Using the Illumina Infinium Human Methylation27 BeadChip, we performed a genome-wide analysis of DNA methylation in right coronary artery in the area of advanced atherosclerotic plaques, atherosclerotic-resistant internal mammary arteries, and great saphenous veins obtained from same patients with coronary heart disease. The resulting DNA methylation patterns were markedly different between all the vascular tissues. The genes hypomethylated in athero-prone arteries to compare with atherosclerotic-resistant arteries were predominately involved in regulation of inflammation and immune processes, as well as development. The great saphenous veins exhibited an increase of the DNA methylation age in comparison to the internal mammary arteries. Gene ontology analysis for genes harboring hypermethylated CpG-sites in veins revealed the enrichment for biological processes associated with the development. Four CpG-sites located within the MIR10B gene sequence and about 1 kb upstream of the HOXD4 gene were also confirmed as hypomethylated in the independent dataset of the right coronary arteries in the area of advanced atherosclerotic plaques in comparison with the other vascular tissues. The DNA methylation differences observed in vascular tissues of patients with coronary heart disease can provide new insights into the mechanisms underlying the development of pathology and explanation for the difference in graft patency after coronary artery bypass grafting surgery.


Assuntos
Aterosclerose/genética , Doença das Coronárias/genética , Vasos Coronários/metabolismo , Epigênese Genética , Artéria Torácica Interna/metabolismo , Placa Aterosclerótica/genética , Veia Safena/metabolismo , Idoso , Aterosclerose/metabolismo , Aterosclerose/patologia , Doença das Coronárias/metabolismo , Doença das Coronárias/patologia , Vasos Coronários/patologia , Ilhas de CpG , Metilação de DNA , Feminino , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Artéria Torácica Interna/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Especificidade de Órgãos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Veia Safena/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA