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1.
Catheter Cardiovasc Interv ; 99(5): 1511-1517, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35238444

RESUMO

BACKGROUND: Optical coherence tomography (OCT) is a high-resolution imaging modality that provides a precise evaluation of coronary anatomy. However, the presence of severe coronary lesions can prevent the required adequate distal contrast flushing resultting in inadequate blood clearance and poor image quality or complete blood shadowing of the underlying vessel wall. OBJECTIVES: The aim of this prospective study was to evaluate the feasibility and safety of a novel "double injection technique" (DIT) to overcome the limitations of the conventional technique (CT) in patients with severely stenotic lesions. METHODS: Twenty-three patients with severe angiographic lesions were sequentially imaged before intervention with OCT with the CT and then with DIT. A total of 5125 OCT frames were carefully matched and analyzed by an independent central core lab. A semiquantitative image quality score was used to grade the number of quadrants (0-4) with vessel wall visualization. RESULTS: Optimal OCT visualization (Grades 3-4) significantly improved by the DIT (68% vs. 38% of frames, p < 0.001). The DIT also improved the mean score (3.1 ± 0.6 vs. 2.0 ± 0.8; p < 0.05; mean improvement of 1.1 ± 0.5 per patient). There were no complications associated with the DIT. CONCLUSION: The DIT significantly improved preintervention image quality of OCT in severe coronary lesions.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/terapia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Humanos , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento , Ultrassonografia de Intervenção
2.
Catheter Cardiovasc Interv ; 97(7): 1309-1317, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32329200

RESUMO

OBJECTIVES: This study aimed to assess the impact of stent optimization by NC-balloon postdilatation (PD) during primary-PCI for STEMI with the use of coronary physiology and intracoronary imaging. METHODS: This was a prospective observational study (ClinicalTrials.gov:NCT02788396). Optical coherence tomography (OCT) and physiological measurements were performed immediately before and after PD with the operators blinded to all measurements. The index of microcirculatory resistance (IMR), coronary flow reserve (CFR) and fractional flow reserve (FFR) were measured. OCT analysis was performed for assessment of stent expansion, malapposition, in-stent plaque-thrombus prolapse (PTP) and stent-edge dissections (SED). The change in IMR before and after PD as a measure of microvascular injury was the primary objective of the study. RESULTS: Thirty-two STEMI patients undergoing primary-PCI had physiological measurements before and after PD. All patients received second-generation DES (diameter 3.1 ± 0.5 mm, length 29.9 ± 10.7 mm) and postdilatation with NC-balloons (diameter 3.6 ± 0.6 mm, inflation pressure 19.3 ± 2.0 atm). IMR (44.9 ± 25.6 vs. 48.8 ± 34.2, p = 0.26) and CFR (1.60 ± 0.89 vs. 1.58 ± 0.71, p = 0.87) did not change, while FFR increased after PD (0.91 ± 0.08 vs. 0.93 ± 0.06, p = 0.037). At an individual patient level, IMR increased in half of the cases. PD improved significantly absolute and relative stent expansion, reduced malapposition, and increased PTP. There was no difference in clinically relevant SED. CONCLUSION: In this exploratory, hypothesis-generating study, postdilatation during primary-PCI for STEMI improved stent expansion, apposition and post-PCI FFR, without a significant effect on coronary microcirculation overall. Nevertheless, IMR increased in a group of patients and larger studies are warranted to explore predictors of microcirculatory response to postdilatation.


Assuntos
Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Humanos , Microcirculação , Intervenção Coronária Percutânea/efeitos adversos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Stents , Tomografia de Coerência Óptica , Resultado do Tratamento
3.
Eur Heart J ; 41(3): 383-391, 2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31504405

RESUMO

AIMS: The CLIMA study, on the relationship between coronary plaque morphology of the left anterior descending artery and twelve months clinical outcome, was designed to explore the predictive value of multiple high-risk plaque features in the same coronary lesion [minimum lumen area (MLA), fibrous cap thickness (FCT), lipid arc circumferential extension, and presence of optical coherence tomography (OCT)-defined macrophages] as detected by OCT. Composite of cardiac death and target segment myocardial infarction was the primary clinical endpoint. METHODS AND RESULTS: From January 2013 to December 2016, 1003 patients undergoing OCT evaluation of the untreated proximal left anterior descending coronary artery in the context of clinically indicated coronary angiogram were prospectively enrolled at 11 independent centres (clinicaltrial.gov identifier NCT02883088). At 1-year, the primary clinical endpoint was observed in 37 patients (3.7%). In a total of 1776 lipid plaques, presence of MLA <3.5 mm2 [hazard ratio (HR) 2.1, 95% confidence interval (CI) 1.1-4.0], FCT <75 µm (HR 4.7, 95% CI 2.4-9.0), lipid arc circumferential extension >180° (HR 2.4, 95% CI 1.2-4.8), and OCT-defined macrophages (HR 2.7, 95% CI 1.2-6.1) were all associated with increased risk of the primary endpoint. The pre-specified combination of plaque features (simultaneous presence of the four OCT criteria in the same plaque) was observed in 18.9% of patients experiencing the primary endpoint and was an independent predictor of events (HR 7.54, 95% CI 3.1-18.6). CONCLUSION: The simultaneous presence of four high-risk OCT plaque features was found to be associated with a higher risk of major coronary events.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Vasos Coronários/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico , Tomografia de Coerência Óptica/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
4.
Eur Heart J Suppl ; 22(Suppl E): E121-E124, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32523455

RESUMO

Inflammation plays an important role in the development of atherosclerotic lesions. A variety of stimuli promote atherosclerosis, including increased LDL cholesterol in blood, exposure to tobacco, diabetes mellitus, hypertension, or rheological stress. Inflammatory cells have an established role in the growth of atherosclerotic lesions. Macrophages recognize and internalise ox-LDL to eventually become lipid-laden foam cells, the hallmark cellular component of atheroma. Infiltrating CD4-T cells have a role too, by interacting with ox-LDL and other antigens. Cytokines secreted by inflammatory cells stimulate smooth muscle cells migration whilst macrophages produce metalloprotease that lead to fibrous cap rupture. The necrotic debris of died macrophages and smooth muscle cells help to continue the inflammatory process. The inflammatory response can also directly activate platelets and promote thrombus formation at the surface of complicated coronary plaques. The CANTOS trial can be waived as an innovative study promoting a novel approach of personalized medicine. In patients with previous myocardial infarction, high-sensitivity C-reactive protein level of 2 mg and normal LDL level (<70 mg/dL), canakinumab a therapeutic monoclonal antibody targeting interleukin-1ß, at a dose of 150 mg every 3 months, led to a significant reduction of the primary efficacy end point: nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death at 48 months. Based on the CANTOS results, patients on statins and residual inflammatory risk as assessed by means of a high-sensitivity CRP >2 mg/l at baseline have a high risk of future cardiac events, comparable to that of statin-treated patients with suboptimal cholesterol LDL level. The inhibition of interleukin-1ß by means of canakinumab, which is only one of many potential anti-inflammatory pathways, open new perspectives, showing that a selective inhibition of the inflammatory pathway may be beneficial in reducing cardiovascular risk. In a process of personalized medicine, there is need to accurately identify patients at high risk of events, to be treated with potent statins or anti-inflammatory drugs. Perhaps in the near future a more specific assessment of coronary inflammations, possibly obtained with imaging modalities (either invasive or non-invasive), will better select patients at risk of events. In this scenario, in the setting of secondary prevention, OCT may serve the scope of identifying vulnerable plaques with local aggregates of inflammatory cells. Future studies are needed to understand the clinical effectiveness of strategies based on invasive coronary assessment.

5.
Eur Heart J Suppl ; 21(Suppl B): B73-B75, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30948956

RESUMO

Improving cardiovascular risk assessment requires a 'personalized' approach. Appraisal of well-known cardiovascular risk factors should be integrated with markers of cardiovascular risk such as LDL cholesterol (C-LDL) and C-reactive protein (CRP). Results of the recent trials of PCSK9 inhibitor monoclonal antibodies open new interesting perspective. Data regarding the use of Evolocumab, in secondary prevention settings, in high-risk patients are very encouraging. In the same vein, the CANTOS study demonstrated, for the first time, that Canakinumbab, an antibody with anti-inflammatory action (with no effects on C-LDL levels), decreases significantly the risk of major cardiovascular events in a high-risk population with elevated CRP and optimal C-LDL. This trial, for the first time, suggested a strategy distinguishing the anti-inflammatory from the cholesterol lowering component, thus differentiating the treatment. In the ensuing years, we will probably witness the clinical application of this concept.

6.
Palliat Support Care ; 17(1): 107-118, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29808788

RESUMO

OBJECTIVE: Qualitative research is pivotal in gaining understanding of individuals' experiences in pediatric palliative care. In the past few decades, the number of qualitative studies on pediatric palliative care has increased slightly, as has interest in qualitative research in this area. Nonetheless, a limited number of such studies have included the first-person perspective of children. The aim of this article is to understand the contribution of previous qualitative research on pediatric palliative care that included the voices of children. METHOD: A systematic review of qualitative studies and a meta-summary were conducted. MEDLINE, CINAHL, PsycINFO, PsycARTICLES, and ERIC were searched without limitations on publication date or language. Eligible articles were qualitative research articles in which the participants were children ranging in age from 3 to 18 years.ResultWe retrieved 16 qualitative research articles reporting on 12 unique studies, and we selected two mixed-method articles. The meta-summary shows eight themes: the relationship with professional caregivers, pain and its management, "living beyond pain," the relationship between pediatric patients and their families, children's view on their treatment and service provision, meanings children give to their end-of-life situation, consequences of clinical decisions, and the relationships among children in pediatric palliative care and their peers.Significance of resultsThis meta-summary presents the "state of the art" of pediatric palliative care qualitative research on children and highlights additional research areas that warrant qualitative study.


Assuntos
Crianças com Deficiência/psicologia , Cuidados Paliativos/normas , Pediatria/normas , Percepção , Adolescente , Criança , Pré-Escolar , Tomada de Decisões , Humanos , Cuidados Paliativos/métodos , Cuidados Paliativos/psicologia , Pediatria/métodos , Pesquisa Qualitativa
7.
Eur J Nucl Med Mol Imaging ; 44(11): 1878-1887, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28584972

RESUMO

PURPOSE: To evaluate the relationship between aortic inflammation as assessed by 18F-fluorodeoxyglucose-positron emission tomography (18F-FDG-PET) and features of plaque vulnerability as assessed by frequency domain-optical coherence tomography (FD-OCT). METHODS: We enrolled 30 consecutive non-ST-segment elevation acute coronary syndrome patients undergoing percutaneous coronary intervention. All patients underwent three-vessel OCT before intervention and 18F-FDG-PET before discharge. Univariable and C-reactive protein (CRP)-adjusted linear regression analyses were performed between features of vulnerability [namely:lipid-rich plaques with and without macrophages and thin cap fibroatheromas (TCFA)] and 18F-FDG uptake in both ascending (AA) and descending aorta (DA) [measured either as averaged mean and maximum target-to-blood ratio (TBR) or as active slices (TBRmax ≥ 1.6)]. RESULTS: Mean age was 62 years, and 26 patients were male. On univariable linear regression analysis TBRmean and TBRmax in DA was associated with the number of lipid-rich plaques (ß = 4.22; 95%CI 0.05-8.39; p = 0.047 and ß = 3.72; 95%CI 1.14-6.30; p = 0.006, respectively). TBRmax in DA was also associated with the number of lipid-rich plaques containing macrophages (ß = 2.40; 95%CI 0.07-4.72; p = 0.044). A significant CRP adjusted linear association between the TBRmax in DA and the number of lipid-rich plaques was observed (CRP-adjusted ß = 3.58; 95%CI -0.91-6.25; p = 0.01). TBRmax in DA showed a trend towards significant CRP-adjusted association with number of lipid-rich plaques with macrophages (CRP-adjusted ß = 2.30; 95%CI -0.11-4.71; p = 0.06). We also observed a CRP-adjusted (ß = 2.34; 95%CI 0.22-4.47; p = 0.031) linear association between the number of active slices in DA and the number of lipid-rich plaques. No relation was found between FDG uptake in the aorta and the number of TCFAs. CONCLUSIONS: In patients with first NSTEACS, 18F-FDG uptake in DA is correlated with the number of OCT detected lipid-rich plaques with or without macrophages. This association may be independent from CRP values.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Angiografia Coronária/métodos , Placa Aterosclerótica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia de Coerência Óptica/métodos , Síndrome Coronariana Aguda/cirurgia , Adulto , Aorta Torácica/patologia , Angiografia Coronária/normas , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos , Tomografia de Coerência Óptica/normas
8.
Catheter Cardiovasc Interv ; 90(4): 566-575, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28295990

RESUMO

OBJECTIVES: Assess clinical consequences of acute stent malapposition (ASM) in the context of the multicenter Centro per la Lotta Contro l'Infarto-Optimization of Percutaneous Coronary Intervention (CLI-OPCI) registry. BACKGROUND: ASM as important determinant of stent thrombosis (ST) risk remains controversial. METHODS: From 2009 to 2013, we retrospectively analyzed postprocedural optical coherence tomography (OCT) findings in 864 patients undergoing percutaneous coronary intervention, assessing prevalence and magnitude of ASM and exploring correlation with outcome, especially ST. RESULTS: Postprocedural OCT revealed a variable grade of ASM in 72.3% of stents without correlation between maximal strut-vessel distance and longitudinal extension (R = 0.164, P < 0.01). At a median follow up of 302 (IQ 127-567) days, ASM did not affect risk of following major cardiac adverse events (MACE); residual ASM was comparable in terms of thickness (median [quartiles] 0.21[IQ 0.1-0.4] vs. 0.20[IQ 0.0-0.3], P = 0.397) and length (2.0[IQ 0.5-4.1] vs. 2.2[IQ 0.0-5.2], P = 0.640) in patients with versus without MACE. The predictive accuracy for outcome was low (C-statistic 0.52, CI 95% 0.47-0.58, P = 0.394) as well for target lesion revascularization (HR 0.80, CI 95% 0.5-1.4) and ST (HR 0.71, CI 95% 0.3-1.5). Likewise, timing to MACE was not influenced by presence of such an ASM with similar rate of acute-subacute (HR 1.09, CI 95% 0.6-1.9), late (HR 0.91, CI 95% 0.5-1.8), and very late (HR 1.23, CI 95% 0.5-2.9) events. CONCLUSIONS: Limited ASM was a common finding after stent implantation, but was not associated to increased risk of stent failure or ST during mid-term follow-up. © 2017 Wiley Periodicals, Inc.


Assuntos
Doença das Coronárias/terapia , Intervenção Coronária Percutânea/instrumentação , Stents , Idoso , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/mortalidade , Reestenose Coronária/epidemiologia , Trombose Coronária/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Prevalência , Falha de Prótese , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia de Coerência Óptica , Resultado do Tratamento
9.
Am Heart J ; 169(2): 249-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25641534

RESUMO

BACKGROUND: Acute or subacute stent thrombosis (ST) is a well-described complication usually causing acute coronary syndromes and, in the worst case scenario, sudden cardiac death. In this study, we aimed at exploring the potential role of optical coherence tomography (OCT) in the understanding of the mechanism of ST. METHODS: Twenty-one consecutive patients, after acute coronary syndromes due to a definite subacute ST, were assessed with OCT and matched 1:2 with 42 patients undergoing OCT for scheduled follow-up. Optical coherence tomography assessment was focused on features indicative of nonoptimal stent deployment: underexpansion, malapposition, edge dissection, and reference lumen narrowing. RESULTS: Optical coherence tomography revealed a minimum stent area sensibly smaller in the ST group (5.6 ± 2.6 vs 6.8 ± 1.7 mm(2); P = .03) with a higher incidence of stent underexpansion when compared with the control group (42.8% vs 16.7%; P = .05). Dissection at stent edges was more commonly detected in ST group (52.4% vs 9.5%; P < .01). No significant differences between the 2 groups were observed for malapposition (52.4% vs 38.1%; P = .651) and reference lumen narrowing (19.0% vs 4.8%; P = .172). At least 1 OCT finding indicative of suboptimal stent deployment was detectable in 95.2% of patients experiencing ST versus 42.9% of the control group (P < .01). CONCLUSIONS: Optical coherence tomography assessment in patients experiencing subacute ST revealed nonoptimal stent deployment in almost all cases with higher incidence of stent underexpansion and edge dissection, potentially explaining the cause of this adverse event. The adoption of an OCT-guided percutaneous coronary intervention protocol could have a potential for the prevention of ST in complex cases.


Assuntos
Síndrome Coronariana Aguda , Remoção de Dispositivo/métodos , Intervenção Coronária Percutânea , Complicações Pós-Operatórias , Stents/efeitos adversos , Tomografia de Coerência Óptica/métodos , Síndrome Coronariana Aguda/etiologia , Síndrome Coronariana Aguda/patologia , Síndrome Coronariana Aguda/fisiopatologia , Síndrome Coronariana Aguda/cirurgia , Idoso , Estudos de Casos e Controles , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/terapia , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Gravidade do Paciente , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Reprodutibilidade dos Testes
10.
Am Heart J ; 170(6): 1116-23, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26678633

RESUMO

BACKGROUND: Thrombus burden and distal embolization are predictive of no-reflow during primary percutaneous coronary intervention (PCI) in patients with acute ST-elevation myocardial infarction (STEMI). We sought to compare the efficacy of pharmacological and catheter-based strategies for thrombus in patients with STEMI and high atherothrombotic burden. METHODS: Between January 2012 and December 2013, 128 STEMI patients undergoing primary PCI at 5 centers were randomly assigned in a 2 × 2 factorial design to intracoronary (IC) abciximab bolus (via the guide catheter) versus intralesion (IL) abciximab bolus, each with versus without aspiration thrombectomy (AT). Study end points were residual intrastent atherothrombotic burden, defined as the number of cross-sections with residual tissue area >10% as assessed by optical coherence tomography, and indices of angiographic and myocardial reperfusion. RESULTS: Residual intrastent atherothrombotic burden did not significantly differ with IL versus IC abciximab (median [interquartile range] 6.0 [1-15] vs 6.0 [2-11], P = .806) and with AT versus no aspiration (6.0 [1-13] vs 6.0 [2-12], P = .775). Intralesion abciximab administration was associated with improved angiographic myocardial reperfusion in terms of thrombolysis in myocardial infarction (TIMI) flow (3 [3-3] vs 3 [2-3], P = .040), corrected TIMI frame count (12 ± 5 vs 17 ± 16, P = .021), and myocardial blush grade (3 [2-3] vs 3 [2-3], P = .035). In particular, IL abciximab was associated with higher occurrence of final TIMI 3 flow (90% vs 73.8%, P = .032) and myocardial blush grade 3 (71.6% vs 52.4%, P = .039). Conversely, AT had no significant effect on indices of angiographic or myocardial reperfusion. CONCLUSIONS: In patients with STEMI and high thrombotic burden, neither IL versus IC abciximab nor AT versus no aspiration reduced postprocedure intrastent atherothrombotic burden in patients with STEMI undergoing primary PCI. However, IL abciximab improved indices of angiographic and myocardial reperfusion compared to IC abciximab, benefits not apparent with AT.


Assuntos
Anticorpos Monoclonais , Reestenose Coronária , Fragmentos Fab das Imunoglobulinas , Infarto do Miocárdio , Intervenção Coronária Percutânea , Complicações Pós-Operatórias , Trombectomia , Trombose , Abciximab , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Angiografia Coronária/métodos , Reestenose Coronária/diagnóstico , Reestenose Coronária/etiologia , Reestenose Coronária/terapia , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Fragmentos Fab das Imunoglobulinas/efeitos adversos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Reperfusão Miocárdica/métodos , Fenômeno de não Refluxo/diagnóstico , Fenômeno de não Refluxo/etiologia , Fenômeno de não Refluxo/terapia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Inibidores da Agregação Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Trombectomia/efeitos adversos , Trombectomia/métodos , Trombose/diagnóstico , Trombose/etiologia , Trombose/terapia , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento
11.
Nature ; 461(7265): 762-7, 2009 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-19767730

RESUMO

Polycomb group proteins have an essential role in the epigenetic maintenance of repressive chromatin states. The gene-silencing activity of the Polycomb repressive complex 2 (PRC2) depends on its ability to trimethylate lysine 27 of histone H3 (H3K27) by the catalytic SET domain of the EZH2 subunit, and at least two other subunits of the complex: SUZ12 and EED. Here we show that the carboxy-terminal domain of EED specifically binds to histone tails carrying trimethyl-lysine residues associated with repressive chromatin marks, and that this leads to the allosteric activation of the methyltransferase activity of PRC2. Mutations in EED that prevent it from recognizing repressive trimethyl-lysine marks abolish the activation of PRC2 in vitro and, in Drosophila, reduce global methylation and disrupt development. These findings suggest a model for the propagation of the H3K27me3 mark that accounts for the maintenance of repressive chromatin domains and for the transmission of a histone modification from mother to daughter cells.


Assuntos
Cromatina/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Inativação Gênica , Histonas/química , Histonas/metabolismo , Proteínas Repressoras/metabolismo , Regulação Alostérica , Animais , Linhagem Celular , Cromatina/química , Cromatina/metabolismo , Cristalografia por Raios X , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster/crescimento & desenvolvimento , Ativação Enzimática , Histona-Lisina N-Metiltransferase/química , Histona-Lisina N-Metiltransferase/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Metilação , Modelos Biológicos , Modelos Moleculares , Proteínas Nucleares/metabolismo , Nucleossomos/química , Nucleossomos/genética , Nucleossomos/metabolismo , Complexo Repressor Polycomb 2 , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Repressoras/química , Proteínas Repressoras/genética , Especificidade por Substrato
12.
Eur Heart J ; 34(10): 729-41, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23186807

RESUMO

AIMS: We aimed to compare coronary artery disease (CAD) at the time of a first acute coronary syndrome (ACS) in type II diabetic and non-diabetic patients by coronary angiography and by optical coherence tomography (OCT). METHODS AND RESULTS: Two different patient populations with a first ACS were enrolled for the angiographic (167 patients) and the OCT (72 patients) substudy. Angiographic CAD severity was assessed by Bogaty, Gensini, and Sullivan scores, whereas collateral development towards the culprit vessel was assessed by the Rentrop score. Optical coherence tomography plaque features were evaluated at the site of the minimum lumen area (MLA) and of culprit segment. In the angiographic substudy, at multivariate analysis, diabetes was associated with both the stenosis score and the extent index (P = 0.001). Furthermore, well-developed collateral circulation (Rentrop 2-3) towards the culprit vessel was more frequent in diabetic than in non-diabetic patients (73% vs. 16%, P = 0.001). In the OCT substudy, at MLA site lipid quadrants were less and the lipid arc was smaller in diabetic than in non-diabetic patients (2.3 ± 1.3 vs. 3.0 ± 1.2; P = 0.03 and 198° ± 121° vs. 260° ± 118°; P = 0.03). Furthermore, the most calcified cross-section along the culprit segment had a greater number of calcified quadrants and a wider calcified arc in diabetic than in non-diabetic patients (1.7 ± 1.0 vs. 1.2 ± 0.9; P = 0.03 and 126° ± 95° vs. 81° ± 80°; P = 0.03). Superficial calcified nodules were more frequently found in diabetic than in non-diabetic patients (79 vs. 54%, P = 0.04). CONCLUSIONS: In spite of potent pro-inflammatory, pro-oxidant and pro-thrombotic stimuli operating in type II diabetes, diabetic patients exhibit substantially more severe coronary atherosclerosis than non-diabetic patients at the time of a first acute coronary event. Better collateral development towards the culprit vessel, a predominantly calcific plaque phenotype and, probably, yet unknown protective factors operating in diabetic patients may explain these intriguing paradoxical findings.


Assuntos
Síndrome Coronariana Aguda/patologia , Doença da Artéria Coronariana/patologia , Diabetes Mellitus Tipo 2/patologia , Cardiomiopatias Diabéticas/patologia , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Circulação Colateral/fisiologia , Angiografia Coronária , Doença da Artéria Coronariana/fisiopatologia , Estenose Coronária/patologia , Estenose Coronária/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Cardiomiopatias Diabéticas/fisiopatologia , Feminino , Humanos , Masculino , Placa Aterosclerótica/patologia , Placa Aterosclerótica/fisiopatologia , Estudos Prospectivos , Fatores de Risco , Tomografia de Coerência Óptica , Calcificação Vascular/patologia , Calcificação Vascular/fisiopatologia
13.
Minerva Cardiol Angiol ; 71(3): 275-283, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-32657556

RESUMO

BACKGROUND: In this in-vivo human study we tested the reproducibility for optical coherence tomography (OCT) assessment of lumen area (LA) and plaque components measurements, such as lipid arc extension and fibrous cap thickness (FCt). METHODS: We tested the variability of LA, lipid arc and FCt assessments in two repeated OCT pullbacks from the same diseased coronary segment matched using fiduciary anatomical landmarks. In particular, for the reliability of minimal FCt measurement we compared four different approaches based on continuous (longitudinal) or segmental (spot) individuation of smaller thickness: 1) comparison of single minimal FCt individuated alongside all plaque extension in the two pullbacks (Longitudinal (L)-spot minimal FCt value); 2) comparison of the mean FCt values of the plaque in the two pullbacks (L-plot mean FCt value); 3) comparison between the single minimal FCt value obtained in the first pullback and the single FCt obtained in the matched CS of second pullback (L-spot CS matched FCt value); 4) comparison of measurements obtained by visual selection of CS with minimal FCt s in the two pullbacks (single-spot minimal FCt value). RESULTS: From the paired analyses of 20 non culprit lesions (accounting for a total of 387 matched CS), we found a suboptimal in-segment correlation for LA (Intra-Class Coefficient [ICC] 0.731), but a good in-segment correlation for lipid arc (ICC 0.963). Regarding FCt measurement, a high reproducibility was obtained applying continuous assessment; in particular, the best correlation was observed with L-spot minimal FCt value and the L-plot mean FCt (ICC 0.893 and 0.952, respectively) with small inter-pullback differences (confidence intervals less than 0.04 mm). CONCLUSIONS: In this methodological study we observed a good reproducibility for quantitative plaque measurements with OCT confirming its reliability for serial assessment. In particular, longitudinal measurement in multiple adjacent frames seems to be the more accurate and reproducible approach for sequential FCt assessment.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Reprodutibilidade dos Testes , Tomografia de Coerência Óptica/métodos , Placa Aterosclerótica/diagnóstico por imagem , Fibrose , Lipídeos
14.
Int J Cardiovasc Imaging ; 39(4): 873-881, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36534217

RESUMO

PURPOSE: To investigate the different impact of optical coherence tomography (OCT)-derived vulnerable plaque features on future adverse events (AEs) according to the biological sex. METHODS: The prospective multicenter CLIMA study (ClinicalTrials.gov: NCT02883088) enrolled 1003 patients with OCT plaque analysis of non-treated coronary plaques located in the proximal left anterior descending artery. Sex-specific differences in plaque composition and vulnerable features were described. We investigated the incidence of AEs, including cardiac death, any myocardial infarction and target vessel revascularization at 1-year. RESULTS: Among 1003 patients, 24.6% were women. Women were older and more frequently affected by chronic kidney disease. Dyslipidemia, prior MI and smoking habit were more common in men. At OCT analysis, women had shorter plaque length (p < 0.001), ticker fibrous cap (p = 0.001), smaller maximum lipid arc (p = 0.019), lower macrophage infiltration (p < 0.001) and intra-plaque layered tissue (p = 0.007). During follow-up, 65 AEs were registered. The presence of a thin fibrous cap and a large macrophage infiltration (> 67°) predicted AEs in both sexes. The presence of macrophages (HR 3.38, p = 0.018) and a small minimum lumen area (HR 4.97, p = 0.002) were associated with AEs in women but not in men, while a large lipid arc (> 180°) was associated with AEs in men (HR 2.56, p = 0.003) but not in women. CONCLUSION: This subanalysis of the CLIMA study investigated for the first-time sex-specific OCT features of plaque vulnerability associated with AEs. Local inflammation was associated with AEs in women and a large lipid arc was predictive in men. OCT may help develop sex-specific risk stratification strategies.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Masculino , Humanos , Feminino , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos , Valor Preditivo dos Testes , Placa Aterosclerótica/patologia , Fibrose , Lipídeos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Angiografia Coronária/métodos
15.
Eur Heart J Cardiovasc Imaging ; 24(4): 437-445, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35718858

RESUMO

AIMS: The aim of this study was to assess the morphological characteristics and prognostic implications of the optical coherence tomography (OCT)-derived lipid core burden index (LCBI). METHODS AND RESULTS: OCT-LCBI was assessed in 1003 patients with 1-year follow-up from the CLIMA multicentre registry using a validated software able to automatically obtain a maximum OCT-LCBI in 4 mm (maxOCT-LCBI4mm). Primary composite clinical endpoint included cardiac death, myocardial infarction, and target-vessel revascularization. A secondary analysis using clinical outcomes of CLIMA study was performed. Patients with a maxOCT-LCBI4mm ≥ 400 showed higher prevalence of fibrous cap thickness (FCT) <75 µm [odds ratio (OR) 1.43, 95% confidence interval (CI) 1.03-1.99; P = 0.034], lipid pool arc >180° (OR 3.93, 95%CI 2.97-5.21; P < 0.001), minimum lumen area <3.5 mm2 (OR 1.5, 95%CI 1.16-1.94; P = 0.002), macrophage infiltration (OR 2.38, 95%CI 1.81-3.13; P < 0.001), and intra-plaque intimal vasculature (OR 1.34, 95%CI 1.05-1.72; P = 0.021). A maxOCT-LCBI4mm ≥400 predicted the primary endpoint [adjusted hazard ratio (HR) 1.86, 95%CI 1.1-3.2; P = 0.019] as well as the CLIMA endpoint (HR 2.56, 95%CI 1.24-5.29; P = 0.011). Patients with high lipid content and thin FCT < 75 µm were at higher risk for adverse events (HR 4.88, 95%CI 2.44-9.72; P < 0.001). CONCLUSIONS: A high maxOCT-LCBI4mm was related to poor outcome and vulnerable plaque features. This study represents a step further in the automated assessment of the coronary plaque risk profile.


Assuntos
Placa Aterosclerótica , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Valor Preditivo dos Testes , Placa Aterosclerótica/diagnóstico por imagem , Fibrose , Lipídeos , Sistema de Registros
16.
Circ Cardiovasc Interv ; 15(9): e011496, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36126136

RESUMO

BACKGROUND: The mismatch between in-stent minimum lumen area (sMLA) and reference vessel lumen area, defined as stent underexpansion (SU), could be an important determinant of stent failure. We tested the clinical predictive value of absolute sMLA in comparison to relative SU in the context of the CLI-OPCI (Centro Per La Lotta Contro L'Infarto-Optimisation of Percutaneous Coronary Intervention) project registry. METHODS: We retrospectively analyzed end procedural optical coherence tomography findings in 1211 patients (1422 lesions) undergoing percutaneous coronary intervention, assessing the prevalence and magnitude of residual SU and exploring correlation with outcome in comparison with sMLA. RESULTS: In our series, both sMLA and SU were related to vessel size and anatomic lesion complexity. When compared with patients without adverse event at follow-up, those experiencing device-oriented cardiovascular events (composite of cardiac death, target vessel myocardial infarction, target lesion revascularization, and stent thrombosis) showed a lower sMLA (5.6±2.1 versus 6.1±2.1 mm2; P=0.011) but a comparable degree of SU (11.6±14.1% versus 11.2±13.3%; P=0.734). The prespecified cutoff value of sMLA <4.5 mm2, documented in 23.8% of cases, was confirmed as independent outcome predictor for device-oriented cardiovascular events (hazard ratio [HR], 2.05 [95% CI, 1.5-2.9]) including target lesion revascularization (HR, 2.43 [95% CI, 1.7-3.5]) and stent thrombosis (HR, 3.23 [95% CI, 1.7-6.3]). A residual SU of 10%, 20%, and 30% was observed in 38.0%, 18.2%, and 7.6% of cases, respectively. No grade of residual SU significantly increased the risk of stent failure, unless if an SU >20% was associated with an sMLA <4.5 mm2 (HR, 3.11 [95% CI, 1.7-5.6]). Finally, an association between stent overexpansion (ie, >110%) and device-oriented cardiovascular events was also observed (HR, 1.60 [95% CI, 1.1-2.3]). CONCLUSIONS: Final absolute sMLA and not relative SU was associated with an increased risk of stent failure. A variable grade of SU was common, but it resulted in being clinically relevant only when associated with an sMLA <4.5 mm2.


Assuntos
Doença da Artéria Coronariana , Trombose , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/terapia , Progressão da Doença , Humanos , Estudos Retrospectivos , Stents/efeitos adversos , Trombose/etiologia , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento
17.
Front Pharmacol ; 13: 860682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548337

RESUMO

DNA replication initiation requires the loading of MCM2-7 complexes at the origins of replication during G1. Replication licensing renders chromatin competent for DNA replication and its tight regulation is essential to prevent aberrant DNA replication and genomic instability. CDT1 is a critical factor of licensing and its activity is controlled by redundant mechanisms, including Geminin, a protein inhibitor of CDT1. Aberrant CDT1 and Geminin expression have been shown to promote tumorigenesis in vivo and are also evident in multiple human tumors. In this study, we developed an in vitro AlphaScreen™ high-throughput screening (HTS) assay for the identification of small-molecule inhibitors targeting the CDT1/Geminin protein complex. Biochemical characterization of the most potent compound, AF615, provided evidence of specific, dose-dependent inhibition of Geminin binding to CDT1 both in-vitro and in cells. Moreover, compound AF615 induces DNA damage, inhibits DNA synthesis and reduces viability selectively in cancer cell lines, and this effect is CDT1-dependent. Taken together, our data suggest that AF615 may serve as a useful compound to elucidate the role of CDT1/Geminin protein complex in replication licensing and origin firing as well as a scaffold for further medicinal chemistry optimisation.

18.
J Cardiovasc Transl Res ; 15(6): 1377-1384, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35437619

RESUMO

The present investigation aims to study the interaction between systemic and intra-plaque inflammation in predicting cardiac events. We investigated C-reactive protein (CRP) levels as well as plaque inflammation with optical coherence tomography (OCT)-detected macrophages in the CLIMA study. 689 patients had admission CRP serum values reported, and high CRP values were defined as ≥ 2 mg/dl. The main study endpoint was a composite of cardiac death, myocardial infarction, and/or target vessel revascularization at 1-year follow-up. At multivariate Cox regression analysis, a large (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.2-4.3; p = 0.013) and superficial (HR 2.78, 95%CI 1.5-5.1; p = 0.001) macrophage arc was predicted of the main composite endpoint in patients with high CRP levels. Patients with large/superficial macrophage accumulation and low CRP levels were not at higher risk of adverse events. The presence of high CRP levels and large/superficial macrophage accumulation at OCT analysis identified patients at higher risk of clinical events.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Humanos , Proteína C-Reativa/metabolismo , Tomografia de Coerência Óptica/métodos , Sistema de Registros , Macrófagos/metabolismo , Inflamação , Doença da Artéria Coronariana/diagnóstico por imagem
19.
Int J Cardiol ; 346: 8-12, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34798205

RESUMO

BACKGROUND: The ability of optical coherence tomography (OCT) to recognize intraplaque macrophage infiltration is now well acknowledged. This post-hoc analysis of the CLIMA study aimed to address the clinical impact of the circumferential extension of OCT-defined macrophages and their location at one year follow-up. METHODS: The multicentre CLIMA study enrolled 1003 patients undergoing OCT evaluation of the untreated proximal left anterior descending (LAD) coronary artery. Measurements of circumferential extension of macrophages and measurements of the distance from intima-lumen contour to macrophages string were performed at the plaque cross-section judged as containing the greatest amount of macrophages. The main study endpoint was a composite of cardiac death, myocardial infarction (MI) and/or target vessel revascularization (TVR). RESULTS: Patients with large macrophage arc (p = 0.001) and superficial macrophage arc (p < 0.001) showed a higher one-year incidence of the main one-year composite endpoint. Consistently hypertension (p = 0.018), family history of CAD (p = 0.046), diabetes mellitus (p = 0.036), lower ejection fraction (p = 0.009) and chronic kidney disease (p = 0.019) were more frequently found in patients experiencing the main composite endpoint. At multivariate Cox regression analysis, fibrous cap thickness < 75 µm (HR 2.51, 95% 1.46-4.32), presence of large (HR 1.97, 95%CI 1.16-3.35, p = 0.012) and superficial (HR 1.72, 95%CI 1.02-2.90; p = 0.040) macrophage arc remained independent predictors of the main composite endpoint. Large macrophage arc was associated with target LAD related MI. CONCLUSION: The present post-hoc analysis of the CLIMA showed that the circumferential extension of macrophages and their location are related to a composite endpoint of cardiac death, MI and/or TVR.


Assuntos
Doença da Artéria Coronariana , Intervenção Coronária Percutânea , Placa Aterosclerótica , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários , Humanos , Macrófagos , Valor Preditivo dos Testes , Fatores de Risco , Tomografia de Coerência Óptica , Resultado do Tratamento
20.
J Struct Biol ; 175(2): 113-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21453775

RESUMO

High-throughput methods to produce a large number of soluble recombinant protein variants are particularly important in the process of determining the three-dimensional structure of proteins and their complexes. Here, we describe a collection of protein expression vectors for ligation-independent cloning, which allow co-expression strategies by implementing different affinity tags and antibiotic resistances. Since the same PCR product can be inserted in all but one of the vectors, this allows efficiency in versatility while screening for optimal expression strategies. We first demonstrate the use of these vectors for protein expression in Escherichia coli, on a set of proteins belonging to the ubiquitin specific protease (USP) Family. We have selected 35 USPs, created 145 different expression constructs into the pETNKI-His-3C-LIC-kan vector, and obtained 38 soluble recombinant proteins for 21 different USPs. Finally, we exemplify the use of our vectors for bacterial co-expression and for expression in insect cells, with USP4 and USP7 respectively. We conclude that our ligation-independent cloning strategy allows for high-throughput screening for the expression of soluble proteins in a variety of vectors in E. coli and in insect cells. In addition, the same vectors can be used for co-expression studies, at least for simple binary complexes. Application in the family of ubiquitin specific proteases led to a number of soluble USPs that are used for functional and crystallization studies.


Assuntos
Clonagem Molecular/métodos , Endopeptidases/genética , Vetores Genéticos , Proteínas Recombinantes/genética , Animais , Automação Laboratorial , Baculoviridae , Sequência de Bases , Linhagem Celular , Endopeptidases/metabolismo , Escherichia coli/genética , Humanos , Dados de Sequência Molecular , Proteínas Recombinantes/metabolismo , Proteases Específicas de Ubiquitina
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