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1.
Circ Cardiovasc Imaging ; 17(1): e016206, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38205656

RESUMO

BACKGROUND: Intensive lipid-lowering therapy may induce coronary atherosclerosis regression. Nevertheless, the factors underlying the effect of lipid-lowering therapy on disease regression remain poorly characterized. Our aim was to determine which characteristics of atherosclerotic plaque are associated with a greater reduction in coronary plaque burden (PB) after treatment with alirocumab in patients with familial hypercholesterolemia. METHODS: The ARCHITECT study (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) is a phase IV, open-label, multicenter, single-arm clinical trial to assess the effect of the treatment with alirocumab for 78 weeks on the coronary atherosclerotic PB and its characteristics in subjects with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent a coronary computed tomographic angiography at baseline and a final one at 78 weeks. Every patient received alirocumab 150 mg subcutaneously every 14 days in addition to high-intensity statin therapy. RESULTS: One hundred and four patients were enrolled. Median age was 53.3 (46.2-59.4) years and 54 were women (51.9%). The global coronary PB changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up, which is -4.6% (-7.7% to -1.9%; P<0.001) reduction. A decrease in the percentage of unstable core (fibro-fatty+necrotic plaque; from 14.1 [7.9-22.3] to 8.0 [6.4-10.6]; -6.6%; P<0.001) was found. A greater PB (ß, 0.36 [0.13-0.59]; P=0.002) and a higher proportion of unstable core (ß, 0.15 [0.08-0.22]; P<0.001) were significantly related to PB regression. CONCLUSIONS: Treatment with alirocumab in addition to high-intensity statin therapy might produce a greater PB regression in patients with familial hypercholesterolemia with higher baseline PB and in those with larger unstable core. Further studies are needed to corroborate the hypothesis raised by these results. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05465278.


Assuntos
Anticorpos Monoclonais Humanizados , Doença da Artéria Coronariana , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Placa Aterosclerótica , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Doença da Artéria Coronariana/induzido quimicamente , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/complicações , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/complicações , Hipercolesterolemia/tratamento farmacológico , LDL-Colesterol/uso terapêutico , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Resultado do Tratamento
2.
Circulation ; 147(19): 1436-1443, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37009731

RESUMO

BACKGROUND: The effect of alirocumab, a PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor, on coronary plaque burden in patients with familial hypercholesterolemia has not been addressed. Our aim was to assess changes in coronary plaque burden and its characteristics after treatment with alirocumab by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of a noninvasive analysis of coronary computed tomographic angiography in asymptomatic subjects with familial hypercholesterolemia receiving optimized and stable treatment with maximum tolerated statin dose with or without ezetimibe. METHODS: This study is a phase IV, open-label, multicenter, single-arm clinical trial to assess changes in coronary plaque burden and its characteristics after 78 weeks of treatment with alirocumab in patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent an initial coronary computed tomographic angiography at baseline and another at 78 weeks. Every patient received 150 mg of alirocumab subcutaneiously every 14 days in addition to high-intensity statin therapy. The main outcome was the change on coronary plaque burden and its characteristics by quantification and characterization of atherosclerotic plaque throughout the coronary tree on the basis of analysis of coronary computed tomographic angiography. RESULTS: The study was completed by 104 patients. The median age was 53.3 (46.2-59.4) years. Of these patients, 54 were women (51.9%). Median low-density lipoprotein cholesterol was 138.9 (117.5-175.3) mg/dL at entry and 45.0 (36.0-65.0) mg/dL at follow-up (P<0.001). Coronary plaque burden changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up (P<0.001). A significant change in the characteristics of the coronary atherosclerosis was also found: an increase in the proportion of calcified (+0.3%; P<0.001) and mainly fibrous (+6.2%; P<0.001) plaque, accompanied by a decrease in the percentage of fibro-fatty (-3.9%; P<0.001) and necrotic plaque (-0.6%; P<0.001). CONCLUSIONS: Treatment with alirocumab in addition to high-intensity statin therapy resulted in significant regression of coronary plaque burden and plaque stabilization on coronary computed tomographic angiography over 78 weeks in these groups of patients with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. ARCHITECT (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) could link and explain ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) results. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT05465278.


Assuntos
Síndrome Coronariana Aguda , Aterosclerose , Doença da Artéria Coronariana , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Hiperlipoproteinemia Tipo II , Placa Aterosclerótica , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Pró-Proteína Convertase 9 , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Hipercolesterolemia/tratamento farmacológico , Placa Aterosclerótica/tratamento farmacológico , Hiperlipoproteinemia Tipo II/complicações , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Síndrome Coronariana Aguda/tratamento farmacológico , Resultado do Tratamento
3.
Eur J Prev Cardiol ; 30(4): 320-328, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36416136

RESUMO

AIMS: Most heterozygous familial hypercholesterolaemia (FH) patients require intensive lipid-lowering therapy (LLT) including PCSK9 inhibitors (PCSK9is) to reach current low-density lipoprotein cholesterol (LDL-C) goals. Persistence with chronic treatment is important to reduce the burden of atherosclerotic cardiovascular disease. We analysed persistence, efficacy, and impact on quality of life (QoL) of PCSK9i in FH patients in clinical practice setting. METHODS AND RESULTS: Spanish Familial Hypercholesterolaemia Cohort Study (SAFEHEART) is an open, prospective study in genetically defined FH patients in Spain. Patients ≥18 years of age (n = 696, 46% females) on stable LLT treated with PCSK9i were analysed. Median LDL-C at starting PCSK9i was 145 mg/dL [interquartile range (IQR), 123-177], 3.8 mmol/L (IQR 3.2-4.6). After a median follow up of 3.7 years (IQR 2.3-4.8), 27 patients (4%) discontinued PCSK9i treatment: 5 temporarily (0.7%) and 22 permanently (3.2%). Persistence with PCSK9i was 96.1% in the whole period. Median LDL-C levels and % LDL-C reduction attained after 1 year of treatment and in the last follow-up visit were 63 mg/dL (IQR 43-88), 1.6 mmol/L (IQR 1.1-2.23); 61 mg/dL (IQR 44-82), 1.6 mmol/L (IQR 1.1-2.1); 57.6% (IQR 39.5-69); and 58% (IQR 44-68), respectively. 2016 and 2019 ESC/EAS LDL-C goals were attained by 77 and 48% of patients, respectively, at the last follow-up visit (P < 0.001). Mean QoL score increased slightly in the first year and remained stable. CONCLUSION: Long-term persistence with PCSK9i in FH patients is very high, with a good QoL. Effectiveness in LDL-C reduction and LDL-C goal achievement dramatically improved with PCSK9i in this high-risk population in clinical practice setting. TRIAL REGISTRATION: ClinicalTrials.gov number NCT02693548.


Assuntos
Anticolesterolemiantes , Inibidores de Hidroximetilglutaril-CoA Redutases , Hiperlipoproteinemia Tipo II , Feminino , Humanos , Masculino , Inibidores de PCSK9 , LDL-Colesterol , Anticolesterolemiantes/uso terapêutico , Pró-Proteína Convertase 9 , Qualidade de Vida , Estudos de Coortes , Estudos Prospectivos , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico
4.
Nano Lett ; 13(3): 1278-84, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23379602

RESUMO

The electrostatic potential distribution across single, isolated, colloidal heterostructured nanorods (NRs) with component materials expected to form a p-n junction within each NR has been measured using scanning Kelvin probe microscopy (SKPM). We compare CdS to bicomponent CdS-CdSe, CdS-PbSe, and CdS-PbS NRs prepared via different synthetic approaches to corroborate the SKPM assignments. The CdS-PbS NRs show a sharp contrast in measured potential across the material interface. We find the measured built-in potential within an individual NR to be attenuated by long-range electrostatic forces between the sample substrate, cantilever, and the measuring tip. Surface potential images were deconvoluted to yield built-in potentials ranging from 375 to 510 meV in the heterostructured NRs. We deduce the overall built-in potential as well as the charge distribution across each segment of the heterostructured NRs by combining SKPM data with simulations of the system.

5.
Nano Lett ; 9(11): 3904-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19751068

RESUMO

In organic solar cells, the efficiency of the exciton transport and dissociation across donor-acceptor (D/A) interfaces is controlled by the nanoscale distribution of the donor and acceptor phases. The observation of photoluminescence quenching is often used as confirmation for efficient exciton dissociation but provides no information on the nanoscopic nature of the exciton transport. Here we demonstrate nanoscale imaging of the exciton transport in films consisting of the conjugated polymer poly(3-hexylthiophene) (P3HT, electron donor) blended with the C60 derivative 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C61 (PCBM, electron acceptor) by a tunneling luminescence spectroscopy based on atomic force microscopy. The excitonic luminescence is significantly enhanced when the conjugated polymer is coupled to the plasmon excitation at the tip (tip-enhanced luminescence). This effect allows one to dramatically improve the detection efficiency of the excitonic luminescence and, consequently, resolve individual domains of the conjugated polymer in which the exciton will recombine before dissociation at the D/A interface. Under thermal annealing conditions promoting the segregation of the donor and acceptor phases, a clear increase of the luminescence is seen from polymer-rich regions, consistent with domains of dimensions much larger than the exciton diffusion length. The described scanning luminescence microscopy can thus be applied to the optimization of the blends used in solar cells.

6.
Nano Lett ; 6(12): 2833-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17163714

RESUMO

In scanning tunneling microscopy (STM), confinement of surface plasmons to the optical cavity formed at the metallic tunneling gap stimulates the emission of light. We demonstrate that quantum dots (QDs) found in such a cavity give rise to discrete, observable transitions in the tunneling luminescence spectrum due to the resonant extinction of the plasmon. The observed resonances represent a fingerprint of the QD and occur at the optical band gap owing to the nearly simultaneous transfer of carriers from both sides of the tunneling gap to the QD. The resonant quenching of surface plasmons enables a new imaging technique, dubbed plasmon resonance imaging, with a spatial resolution potentially similar to that of STM and the energy resolution of optical spectroscopies. This detection and imaging strategy is not restricted to QDs, being of great interest to an entire spectrum of nanostructures, from molecular assemblies and biomolecules to carbon nanotubes.

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