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1.
Sci Rep ; 14(1): 2956, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316845

RESUMEN

Many mechanical applications take advantage of spiral torsion springs due to their robustness, compactness, and simplicity. Brand-new manufacturing methods allow to create spiral springs with unconventional geometries and materials that suit a wider range of uses demanding either linearity or nonlinearity. Designing a spiral torsion spring with a nonlinear desired torque curve may be a great challenge, due to their many degrees-of-freedom (length, width, thickness, arbor, and barrel diameters, etc.) and the complexity of the geometrical and mechanical requirements to ensure their manufacturability, system compatibility, operation safety and reliability; and the solution is never unique. This manuscript proposes and validates an innovative methodology for the resolution of this inverse design problem based on the application of a nonlinear restrained global optimization algorithm. This algorithm is adjusted to converge, out of the infinity of designs that match the desired torque curve and hold all the functional and manufacturing constraints, to a design solution that minimizes strip mass. The methodology is built on a formulation for the calculation of the torque curve of a generalized spiral spring, with or without coiling and with any along-the-length cross-section, already published by the authors.

2.
J Geriatr Oncol ; 15(3): 101642, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37977899

RESUMEN

Population aging represents a critical issue for global cancer care, notably in low- and middle-income countries (LMIC). Latin America is a large region composed of 21 countries with notable diversity in both human development and access to quality healthcare. Thus, it is necessary to understand how care for older individuals is being delivered in such large and diverse regions of the world. This review describes the recent advances made in Mexico, Brazil, and Chile, focusing on the creation and implementation of educational, research, and clinical activities in geriatric oncology. These initiatives intend to change healthcare professionals' perceptions about the care for older adults and to improve the way older patients are being treated.


Asunto(s)
Neoplasias , Humanos , Anciano , América Latina/epidemiología , Neoplasias/terapia , Oncología Médica , México , Envejecimiento
3.
Sci Rep ; 12(1): 5350, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-35354890

RESUMEN

Air pollutants increase the risk and mortality of myocardial infarction (MI). The aim of this study was to assess the inflammatory changes in circulating immune cells and microRNAs in MIs related to short-term exposure to air pollutants. We studied 192 patients with acute coronary syndromes and 57 controls with stable angina. For each patient, air pollution exposure in the 24-h before admission, was collected. All patients underwent systematic circulating inflammatory cell analyses. According to PM2.5 exposure, 31 patients were selected for microRNA analyses. STEMI patients exposed to PM2.5 showed a reduction of CD4+ regulatory T cells. Furthermore, in STEMI patients the exposure to PM2.5 was associated with an increase of miR-146a-5p and miR-423-3p. In STEMI and NSTEMI patients PM2.5 exposure was associated with an increase of miR-let-7f-5p. STEMI related to PM2.5 short-term exposure is associated with changes involving regulatory T cells, miR-146a-5p and miR-423-3p.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , MicroARNs , Infarto del Miocardio , Contaminantes Atmosféricos/toxicidad , Biomarcadores , Humanos , MicroARNs/genética , Infarto del Miocardio/genética
4.
Ann Thorac Surg ; 103(2): e157-e159, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28109378

RESUMEN

Left ventricular pseudoaneurysm (LVPsA) is a rare complication after sutureless patch repair of left ventricular free wall rupture (LVFWR), with few cases reported in the literature so far. We present the case of a young patient who early developed a huge LVPsA and moderate mitral regurgitation after sutureless patch repair for LVFWR after undergoing a successful Dor procedure using the "triple empanada patch technique" to exclude the LVPsA, remodel the left ventricle, and address the moderate mitral regurgitation. Serial echocardiograms during follow-up are strongly recommended, even in patients with successful patch repair, to facilitate timely diagnosis and management.


Asunto(s)
Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/cirugía , Aneurisma Cardíaco/cirugía , Rotura Cardíaca Posinfarto/cirugía , Adulto , Aneurisma Falso/etiología , Procedimientos Quirúrgicos Cardíacos/métodos , Angiografía por Tomografía Computarizada/métodos , Estudios de Seguimiento , Aneurisma Cardíaco/diagnóstico por imagen , Aneurisma Cardíaco/etiología , Rotura Cardíaca Posinfarto/etiología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Infarto del Miocardio/complicaciones , Infarto del Miocardio/diagnóstico por imagen , Cuidados Preoperatorios , Medición de Riesgo , Índice de Severidad de la Enfermedad , Procedimientos Quirúrgicos sin Sutura/efectos adversos , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/métodos
5.
Expert Opin Drug Deliv ; 14(7): 841-850, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27718756

RESUMEN

INTRODUCTION: Drug-eluting balloons (DEB) may be considered as a 'quiet revolution' in percutaneous coronary interventions. Early-generation DEB eluting paclitaxel proved to be very effective in animal models to reduce neointimal hyperplasia. Areas covered: Review of DEB efficacy in patients with coronary de novo lesions and in-stent restenosis (ISR). Expert opinion: Many randomized clinical trials and meta-analyses have demonstrated the value of DEB in patients with ISR. In this setting, DEB are safe and effective with clinical and angiographic results superior to plain balloon angioplasty and at least equivalent to first generation drug-eluting stents (DES). In selected 'de novo' lesions (bifurcation lesions, small vessels, diffuse disease, myocardial infarction) DEB represent an attractive alternative although additional evidence in these 'niche' indications is still required before a widespread clinical utilization can be recommended. Recently, new generation DEB have become available, offering interesting new possibilities (paclitaxel and also sirolimus) for coronary interventions. Further studies are required to compare the results of novel generation DEB with those of second-generation DES.


Asunto(s)
Reestenosis Coronaria/terapia , Intervención Coronaria Percutánea/métodos , Angioplastia Coronaria con Balón , Animales , Stents Liberadores de Fármacos , Humanos , Paclitaxel/administración & dosificación , Sirolimus/administración & dosificación , Resultado del Tratamiento , Moduladores de Tubulina/administración & dosificación
6.
Rev Esp Cardiol (Engl Ed) ; 70(12): 1050-1058, 2017 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28495489

RESUMEN

INTRODUCTION AND OBJECTIVES: Stent thrombosis (ST) is a rare but potentially serious complication. Optical coherence tomography (OCT) provides high-resolution images and additional information to angiography in the study of this event. METHODS: Prospective study of patients with ST undergoing reintervention with OCT imaging. RESULTS: The study included a total of 40 consecutive patients with ST. Mean age was 69 ± 13 years and 83% were male. Early ST (≤ 30 days) was observed in 16 patients and late ST (> 30 days) in 24 patients. Stent thrombosis occurred in 17 bare-metal stents and 23 drug-eluting stents. In 34 patients (85%), adequate OCT images were obtained at the time of the ST. The predominant mechanism in early ST was stent malapposition (39%). In late ST, high frequencies of uncovered (46%) and malapposed struts (17%) were observed, especially in patients with drug-eluting stents. Furthermore, the presence of neoatherosclerosis was very high (67%) in patients with late ST. After intervention, improvements were observed in malapposition length and the amount of residual thrombus. CONCLUSIONS: OCT allows identification of the underlying mechanisms potentially involved in ST. This imaging modality is helpful in guiding reintervention in these patients, which improves the area and length of malapposition, as well as the maximal residual thrombus area.


Asunto(s)
Enfermedad de la Arteria Coronaria/cirugía , Trombosis Coronaria/diagnóstico por imagen , Stents Liberadores de Fármacos , Isquemia Miocárdica/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Angina Inestable/diagnóstico por imagen , Angina Inestable/etiología , Angiografía Coronaria , Trombosis Coronaria/complicaciones , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Isquemia Miocárdica/etiología , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Infarto del Miocardio sin Elevación del ST/etiología , Estudios Prospectivos , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/etiología , Stents , Tomografía de Coherencia Óptica
7.
Cardiol J ; 23(6): 647-651, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27976794

RESUMEN

BACKGROUND: Our aim was to prospectively analyze the usefulness of mother-and-child catheter approach with the GuideLiner® (GL) catheter extension system to overcome some potential limitations associated with the use of optical coherence tomography (OCT). METHODS: We included consecutive patients referred to our institution for coronary angiogram in whom OCT image acquisition was obtained using GL. From February 2015 to May 2016, a total of 19 procedures (18 patients) were prospectively included. RESULTS: In more than two thirds of the procedures, the OCT catheter was unable to cross the coronary stenosis prior to the use of GL. The right coronary artery was the most frequently involved coronary vessel (63%). The main reason for using GL (47% of cases) was poor engagement of the coronary ostium and lack of support of the guiding catheter (47%). Eventually, in 18 out of 19 procedures, a good quality OCT image was obtained and, when indicated, successful percutaneous coronary intervention with stent implantation was performed. Of note, there were no serious complications related to the use of GL during OCT imaging. CONCLUSIONS: Optical coherence tomography through a catheter extension system is a useful technique able to overcome some of the limitations associated with this imaging technique ensuring adequate blood clearance and thus optimal image quality.


Asunto(s)
Catéteres Cardíacos , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Intervención Coronaria Percutánea , Tomografía de Coherencia Óptica/instrumentación , Anciano , Enfermedad de la Arteria Coronaria/cirugía , Vasos Coronarios/cirugía , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos
13.
Rev. Hosp. Clin. Univ. Chile ; 16(2): 117-123, 2005.
Artículo en Español | LILACS | ID: lil-445733

RESUMEN

La Ginecomastia es una condición frecuente especialmente en la pubertad y edad adulta, no obstante en ocasiones produce en el paciente un importante grado de ansiedad y discomfort social. Si bien la mayoría de las veces no representa un desafío clínico diagnóstico, puede ser la manifestación inicial de un gran numero de condiciones médicas de mayor importancia para el pronóstico del paciente. De capital importancia es el diagnóstico diferencial con el cáncer de mama masculino, que si bien es de presentación mas bien excepcional, puede ser resuelto con un tratamiento precoz. El presente articulo es una revisión de los aspectos más trascendentes a considerar en el enfrentamiento clínico y terapéutico de esta condición.


Asunto(s)
Masculino , Adolescente , Adulto , Humanos , Ginecomastia/cirugía , Ginecomastia/terapia , Ginecomastia/diagnóstico , Ginecomastia/epidemiología
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