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1.
Phys Rev Lett ; 123(1): 013601, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31386390

RESUMO

Heisenberg's uncertainty principle implies that the quantum vacuum is not empty but fluctuates. These fluctuations can be converted into radiation through nonadiabatic changes in the Hamiltonian. Here, we discuss how to control this vacuum radiation, engineering a single-photon emitter out of a two-level system (2LS) ultrastrongly coupled to a finite-band waveguide in a vacuum state. More precisely, we show the 2LS nonlinearity shapes the vacuum radiation into a non-Gaussian superposition of even and odd cat states. When the 2LS bare frequency lays within the band gaps, this emission can be well approximated by individual photons. This picture is confirmed by a characterization of the ground and bound states, and a study of the dynamics with matrix-product states and polaron Hamiltonian methods.

2.
J Thromb Haemost ; 15(3): 575-585, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28039962

RESUMO

Essentials Abdominal aortic aneurysm (AAA) is asymptomatic and its evolution unpredictable. To find novel potential biomarkers of AAA, microvesicles are an excellent source of biomarkers. Ficolin-3 is increased in microvesicles obtained from activated platelets and AAA tissue. Increased ficolin-3 plasma levels are associated with AAA presence and progression. SUMMARY: Background Abdominal aortic aneurysm (AAA) patients are usually asymptomatic and AAA evolution is unpredictable. Ficolin-3, mainly synthesized by the liver, is a molecule of the lectin complement-activation pathway involved in AAA pathophysiology. Objectives To define extra-hepatic sources of ficolin-3 in AAA and investigate the role of ficolin-3 as a biomarker of the presence and progression of AAA. Methods Microvesicles (exosomes and microparticles) were isolated from culture-conditioned medium of ADP-activated platelets, as well as from AAA tissue-conditioned medium (thrombus and wall). Ficolin-3 levels were analyzed by western-blot, real-time PCR, immunohistochemistry and ELISA. Results Increased ficolin-3 levels were observed in microvesicles isolated from activated platelets. Similarly, microvesicles released from AAA tissue display increased ficolin-3 levels as compared with those from healthy tissue. Moreover, ficolin-3 mRNA levels in the AAA wall were greatly increased compared with healthy aortic walls. Immunohistochemistry of AAA tissue demonstrated increased ficolin-3, whereas little staining was present in healthy walls. Finally, increased ficolin-3 levels were observed in AAA patients' plasma (n = 478) compared with control plasma (n = 176), which persisted after adjustment for risk factors (adjusted odds ratio [OR], 5.29; 95% confidence interval [CI], 3.27, 8.57)]. Moreover, a positive association of ficolin-3 with aortic diameter (Rho, 0.25) and need for surgical repair was observed, also after adjustment for potential confounding factors (adjusted hazard ratio, 1.55; 95% CI, 1.11, 2.15). Conclusions In addition to its hepatic expression, ficolin-3 may be released into the extracellular medium via microvesicles, by both activated cells and pathological AAA tissue. Ficolin-3 plasma levels are associated with the presence and progression of AAA, suggesting its potential role as a biomarker of AAA.


Assuntos
Aneurisma da Aorta Abdominal/sangue , Glicoproteínas/sangue , Lectinas/sangue , Idoso , Biomarcadores/sangue , Plaquetas/metabolismo , Meios de Cultivo Condicionados/química , Dinamarca , Progressão da Doença , Humanos , Hipertensão/diagnóstico , Masculino , Programas de Rastreamento , Microcirculação , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico
3.
Phys Rev Lett ; 113(26): 263604, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615332

RESUMO

The scattering of a flying photon by a two-level system ultrastrongly coupled to a one-dimensional photonic waveguide is studied numerically. The photonic medium is modeled as an array of coupled cavities and the whole system is analyzed beyond the rotating wave approximation using matrix product states. It is found that the scattering is strongly influenced by the single- and multiphoton dressed bound states present in the system. In the ultrastrong coupling regime a new channel for inelastic scattering appears, where an incident photon deposits energy into the qubit, exciting a photon-bound state, and escaping with a lower frequency. This single-photon nonlinear frequency conversion process can reach up to 50% efficiency. Other remarkable features in the scattering induced by counterrotating terms are a blueshift of the reflection resonance and a Fano resonance due to long-lived excited states.

4.
Br J Pharmacol ; 169(3): 493-511, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23488589

RESUMO

High-density lipoproteins (HDLs) represent a family of particles characterized by the presence of apolipoprotein A-I (apoA-I) and by their ability to transport cholesterol from peripheral tissues back to the liver. In addition to this function, HDLs display pleiotropic effects including antioxidant, anti-apoptotic, anti-inflammatory, anti-thrombotic or anti-proteolytic properties that account for their protective action on endothelial cells. Vasodilatation via production of nitric oxide is also a hallmark of HDL action on endothelial cells. Endothelial cells express receptors for apoA-I and HDLs that mediate intracellular signalling and potentially participate in the internalization of these particles. In this review, we will detail the different effects of HDLs on the endothelium in normal and pathological conditions with a particular focus on the potential use of HDL therapy to restore endothelial function and integrity.


Assuntos
Endotélio Vascular/metabolismo , Lipoproteínas HDL/metabolismo , Modelos Biológicos , Receptores de Lipoproteínas/metabolismo , Vasculite/metabolismo , Animais , Apoptose , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Angiopatias Diabéticas/imunologia , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/fisiopatologia , Angiopatias Diabéticas/terapia , Sistemas de Liberação de Medicamentos , Endotélio Vascular/imunologia , Endotélio Vascular/fisiopatologia , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas HDL/uso terapêutico , Lisofosfolipídeos , Esfingosina/análogos & derivados , Vasculite/imunologia , Vasculite/fisiopatologia , Vasculite/terapia
5.
Clín. investig. arterioscler. (Ed. impr.) ; 22(supl.1): 44-48, abr. 2010. tab
Artigo em Espanhol | IBECS | ID: ibc-145474

RESUMO

La CETP (cholesteryl ester transfer protein) es la proteína responsable de la transferencia de lípidos neutros entre las lipoproteínas. La CETP juega un papel clave en la homeostasis del colesterol, especialmente en la redistribución de colesterol entre partículas y en el transporte reverso de colesterol, por lo que la modificación de su actividad puede modificar el desarrollo y la evolución de la ateromatosis. Los efectos de la inhibición de CETP incluyen: reducción de colesterol LDL y aumento del colesterol HDL y apo A-1, aumento en el tamaño de las partículas LDL y HDL, y reducción del colesterol en las partí- culas ricas en triglicéridos. En consonancia, la inducción de expresión de la actividad CETP en ratones aumenta la susceptibilidad a la aterosclerosis mientras que la inhibición de la actividad CETP en conejos tiende a reducir su desarrollo. Sin embargo, el papel de la inhibición de CETP en la ateromatosis en humanos está todavía por definir (AU)


Cholesteryl ester transfer protein (CETP) facilitates transfer of neutral lipids between lipoprotein classes. CETP plays a key role in cholesterol homeostasis, especially in the redistribution of cholesterol among particles and in reverse cholesterol transport. Consequently, modifying the activity of this protein could influence the development and progression of atheromatosis. The effects of inhibiting CETP include reductions in lowdensity lipoprotein (LDL)-cholesterol and cholesterol in triglyceride-rich particles and increases in high-density lipoprotein (HDL)-cholesterol, apolipoprotein A-1 and the size of LDL and HDL particles. The induction of expression of CETP activity in mice increases susceptibility to atherosclerosis, while inhibition of CETP activity in rabbits tends to reduce its development. However, the role of CETP inhibition in atheromatosis in humans remains to be established (AU)


Assuntos
Feminino , Humanos , Masculino , HDL-Colesterol/administração & dosagem , HDL-Colesterol/metabolismo , Doença da Artéria Coronariana/patologia , Abetalipoproteinemia/metabolismo , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Glicoproteínas/administração & dosagem , Glicoproteínas , HDL-Colesterol/deficiência , HDL-Colesterol/uso terapêutico , Doença da Artéria Coronariana/metabolismo , Abetalipoproteinemia/complicações , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/instrumentação , Glicoproteínas/metabolismo , Glicoproteínas/provisão & distribuição
8.
Actas Urol Esp ; 23(7): 629-33, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-10488621

RESUMO

INTRODUCTION: The extragonadal germ-cell tumors (EGGCT) represent 5% of all germ-cell tumors at presentation. Histologically, they are identical to testis germ cell tumors. They may arise in such sites as the mediastinum, retroperitoneal area, sacrococcygeal area, or pineal area without a primary in the testis. MATERIAL AND METHODS: The medical records of 10 patients with mediastinal EGGCT were reviewed between 1973 and 1996. All patients were males and his mean age was 26.7 years old (21-24). Follow-up was 19 months (3-72). RESULTS: The first symptoms are diverse. The histology results nonseminomatous tumor at 9 patients and seminomatous tumor at the restant. All of the scrotal examination was normal and only five patients presented increased tumoral markers (alpha-FP in 4 and beta-HCG in 1). Previous at 1990 didn't exist a standard treatment, resulting the four patients treated in this period exitus. After 1990 the treatment was cisplatin-based chemotherapy: BEP (bleomicyn, etoposide-VP-16- and cisplatin-CDDP) then we obtained the best results, a patient died after 6 months but the restants five are alive and without evidence of disease during a follow-up between 3 and 72 months.


Assuntos
Germinoma/diagnóstico , Neoplasias do Mediastino/diagnóstico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Seguimentos , Germinoma/patologia , Germinoma/terapia , Humanos , Masculino , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/terapia , Radioterapia Adjuvante
9.
Actas Urol Esp ; 23(10): 888-94, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-10670134

RESUMO

We present a 15-year-old male patient diagnosed histopathologically as suffering from Ask-Upmark kidney, in the absence of vesicoureteral reflux and with hypertension. The first clinical manifestation was completely atypical: right loin pain, with so many agudisation treated at our emergency serve that justified a thorough study. The pathogenesis of the Ask-Upmark kidney is still unknown; some authors defend the congenital malformation hypothesis, as it was first described in 1929, but there are groups who support the Ask-Upmark kidney as a form of reflux nephropathy. After our description we present a review of the literature.


Assuntos
Rim/anormalidades , Rim/patologia , Adolescente , Humanos , Masculino
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