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1.
Sci Rep ; 14(1): 4945, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418538

RESUMO

We introduce a novel, gaseous target optical shaping laser set-up, capable to generate short scale length, near-critical target profiles via generated colliding blast waves. These profiles are capable to maintain their compressed density for several nanoseconds, being therefore ideal for laser-plasma particle acceleration experiments in the near critical density plasma regime. Our proposed method overcomes the laser-target synchronization limitations and delivers energetic protons, during the temporal evolution of the optically shaped profile, in a time window of approximately 2.5 ns. The optical shaping of the gas-jet profiles is optimised by MagnetoHydroDynamic simulations. 3D Particle-In-Cell models, adopting the spatiotemporal profile, simulate the 45 TW femtosecond laser plasma interaction to demonstrate the feasibility of the proposed proton acceleration set-up. The optical shaping of gas-jets is performed by multiple, nanosecond laser pulse generated blastwaves. This process results in steep gradient, short scale length plasma profiles, in the near critical density regime allowing operation at high repetition rates. Notably, the Magnetic Vortex Acceleration mechanism exhibits high efficiency in coupling the laser energy into the plasma in the optically shaped targets, resulting to collimated proton beams of energies up to 14 MeV.

3.
Clin Res Cardiol ; 106(5): 322-330, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27957627

RESUMO

BACKGROUND/INTRODUCTION: The efficacy of catheter-based renal sympathetic denervation (RDN) in terms of blood pressure (BP) reduction has been questioned, while "real-world" data from registries are needed. In this study, we report the complete set of 12-month data on office and ambulatory BP changes as well as the predictors for BP response to RDN from a national registry. METHODS: In 4 Greek hospital centers, 79 patients with severe drug-resistant hypertension (age 59 ± 10 years, 53 males, body mass index 33 ± 5 kg/m2; office BP and 24-h ambulatory BP were 176 ± 15/95 ± 13 and 155 ± 14/90 ± 12 mmHg, respectively, 4.4 ± 0.9 antihypertensive drugs) underwent RDN and were followed-up for 12 months in the Greek Renal Denervation Registry. Bilateral RDN was performed using percutaneous femoral approach and standardized techniques. RESULTS: Reduction in office systolic/diastolic BP at 6 and 12 months from baseline was -30/-12 and -29/-12 mmHg, while the reduction in 24-h ambulatory BP was -16/-9 and -15/-9 mmHg, respectively (p < 0.05 for all). Patients that were RDN responders (85%, n = 58), defined as an at least 10-mmHg decrease in office systolic BP at 12 months, compared to non-responders were younger (57 ± 9 vs 65 ± 8 years, p < 0.05), had higher baseline office systolic BP (176 ± 17 vs 160 ± 11 mmHg, p < 0.05) and 24-h systolic BP (159 ± 13 vs 149 ± 11 mmHg, p < 0.05). Stepwise logistic regression analysis revealed that age, obesity parameters, and baseline office BP were independent predictors of RDN response (p < 0.05 for both), but not the type of RDN catheter or the use of aldosterone antagonists. At 12 months, there were no significant changes in renal function and any new serious device or procedure-related adverse events. CONCLUSIONS: In our "real-world" multicenter national registry, the efficacy of renal denervation in reducing BP as well as safety is confirmed during a 12-month follow-up. Moreover, younger age, obesity, and higher levels of baseline systolic BP are independently related to better BP response to RDN.


Assuntos
Determinação da Pressão Arterial/estatística & dados numéricos , Pressão Sanguínea , Hipertensão Renal/fisiopatologia , Hipertensão Renal/terapia , Rim/fisiopatologia , Sistema de Registros , Simpatectomia/métodos , Doença Crônica , Feminino , Grécia , Humanos , Hipertensão Renal/diagnóstico , Rim/inervação , Rim/cirurgia , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
4.
Herz ; 40 Suppl 1: 36-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25471205

RESUMO

AIMS: The aim of this study was to assess the occurrence of distal embolization and to quantify the amount of embolic material captured during stent implantation in native coronary arteries, as compared with saphenous vein grafts (SVG) in patients at different time periods after an acute coronary syndrome. PATIENTS AND METHODS: In all, 104 patients presenting with unstable or stable angina underwent percutaneous coronary intervention (PCI) in 107 vessels and stent implantation in 112 lesions, 53 % of which were in SVG. RESULTS: Device deployment and retrieval was successful in 111 lesions. Embolic material was detected in 74 % of the protection devices. Early PCI, during a 2-week period after the last ischemic episode, was associated with larger embolic load, especially in the right coronary artery. The length of the lesion was the only preprocedural independent variable that was found to be a significant predictor for the presence of emboli (p = 0.002). The stent diameter and the maximum dilatation pressure were the two procedural variables found to be significant predictors for the presence of emboli (p = 0.025 and p = 0.008, respectively). The irregularity of the lesion and the number of stents deployed were found to have a predictive correlation to the total area of the embolic particles (p = 0.04 and p = 0.005, respectively). CONCLUSION: Distal embolization of atherosclerotic debris is a frequent phenomenon after PCI not only in SVG but also in native vessels. The amount of embolic material seems to be related to the atherosclerotic burden of the vessel and to the early timing of the procedure as related to acute coronary syndrome.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/terapia , Vasos Coronários/transplante , Embolização Terapêutica/métodos , Intervenção Coronária Percutânea/instrumentação , Veia Safena/transplante , Prótese Vascular , Terapia Combinada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Stents , Resultado do Tratamento
5.
Proc AMIA Symp ; : 479-83, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12463870

RESUMO

The Citizen Health System (CHS) is a European Commission (EC) funded project in the field of IST for Health. Its main goal is to develop a generic contact center which in its pilot stage can be used in the monitoring, treatment and management of chronically ill patients at home in Greece, Spain and Germany. Such contact centers, which can use any type of communication technology, and can provide timely and preventive prompting to the patients are envisaged in the future to evolve into well-being contact centers providing services to all citizens. In this paper, we present the structure of such a generic contact center and in particular the telecommunication infrastructure, the communication protocols and procedures, and finally the educational modules that are integrated into this contact center. We discuss the procedures followed for two target groups of patients where two randomized control clinical trials are under way, namely diabetic patients with obesity problems, and congestive heart failure patients. We present examples of the communication means between the contact center medical personnel and these patients, and elaborate on the educational issues involved.


Assuntos
Serviços de Assistência Domiciliar , Monitorização Fisiológica/métodos , Telemedicina , Doença Crônica , Diabetes Mellitus , Europa (Continente) , Insuficiência Cardíaca , Humanos , Internet , Multilinguismo , Obesidade , Integração de Sistemas , Telecomunicações/instrumentação , Telecomunicações/organização & administração
6.
Life Support Syst ; 3 Suppl 1: 167-71, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3870559

RESUMO

This study aims at evaluating the effect of a small spherical balloon functioning during acute mitral regurgitation. Acute mitral regurgitation was produced in 11 mongrel dogs with a specially designed curved blade introduced through the left ventricular apex. Left atrial pressure, electrocardiogram, left ventricular pressure (in 8 dogs) and aortic flow (in 7 dogs) were monitored. The mean left atrial pressure increased by 9.45 +/- 2.44 mmHg (p less than 0.01) and the v wave by 14.09 +/- 2.94 mmHg (p less than 0.001). The systolic left ventricular pressure and the aortic flow decreased. The heart remained in sinus rhythm & the rate did not change significantly. After the production of mitral regurgitation, a small spherical balloon (9 to 16 cc capacity) mounted on a catheter was introduced to the left ventricle through the apex and positioned in the mitral ring. The balloon was inflated by means of a pump during systole and deflated during diastole. During its function the mean left atrial pressure decreased by 4.37 +/- 0.84 mmHg (p less than 0.001) and the v wave by 8.64 +/- 1.23 mm Hg (p less than 0.001). The systolic left ventricular pressure and the aortic flow increased. The peak systolic gradient across the mitral valve increased by 20.5 +/- 3.86 mmHg (p less than 0.01). The heart rate did not change. It is suggested that in acute mitral regurgitation the function of a small balloon could improve the hemodynamic condition by acting as a valve at the mitral ring for reduction of regurgitation and possibly by improving systolic function in severe heart failure.


Assuntos
Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral/cirurgia , Animais , Cateterismo , Cães , Hemodinâmica , Valva Mitral , Insuficiência da Valva Mitral/fisiopatologia
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