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1.
Ultrasonics ; 142: 107387, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38971005

RESUMO

The ultrasonic pulse-echo technique is widely employed to measure the wall thickness reduction due to corrosion in pipelines. Ultrasonic monitoring is noninvasive and can be performed online to evaluate the structural health of pipelines. Although ultrasound is a robust technique, it presents two main difficulties arising from the temperature variation in the medium being monitored: the mechanical assembly must have high stability and the ultrasonic propagation velocity must take into account the temperature variation. In this paper, a detailed strategy is presented to compensate for changes in the propagation velocity whenever the temperature changes. The method is considered self-compensated because the calibration data is obtained from the ultrasonic signals captured using the pipe under evaluation. The analysis of systematic errors in the temperature compensation is presented, first considering that a reference initial pipe thickness is given, and second when a reference sound velocity is given. The technique was evaluated under laboratory conditions using a closed loop with accelerated corrosion through the use of continuous flow saline water containing sand. In this test, the ultrasonic results were compared with the traditional coupon method used to determine corrosion loss. The results show that the self-compensated method was able to compensate for temperature fluctuations, and the total thickness loss measured by the ultrasound technique was close to the value measured by the coupons. Finally, the measurement system was tested in a production pipeline exposed to sunlight. The results show that the self-compensated method can reduce the oscillations in the thickness loss readings, caused by temperature swings, but large temperature variations cannot be completely compensated for. This experiment also shows the effects of low mechanical stability, which caused completely invalid results.

2.
Interv Neuroradiol ; : 15910199241231018, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689478

RESUMO

BACKGROUND: The PEDESTRIAN registry demonstrated high rates of complete long-term occlusion and good clinical outcomes among patients with intracranial aneurysms treated with the pipeline embolization device. The pipeline flex embolization device with shield technology was introduced to minimize thromboembolic complications. In this study, we investigated the safety and effectiveness of pipeline embolization device with shield technology among all patients treated for intracranial aneurysms at our center. METHODS: This was a single-arm retrospective study of prospectively collected data of patients treated with pipeline embolization device with shield technology at our high-volume center between January 2018-January 2021. The primary efficacy endpoint was complete occlusion as measured by a class 1 Raymond-Roy score at 1-year and 2-year follow-up. The primary safety endpoint was major morbidity and neurological mortality up to 1 year following intervention. RESULTS: A total of 328 patients (mean age 56.1 ± 14.7 years; 81.1% female), 80 of whom were previously included in PEDESTRIAN, with 396 aneurysms, were analyzed. A total of 378 devices were deployed, with 93.9% (372/396) of aneurysms requiring only one device. Follow-up angiography was available for 90.2% (296/328) of the procedures after a mean time of 14.0 ± 8.2 months. Complete occlusion was demonstrated for 78.5% (132/168) of aneurysms at 12 months and 90.7% (98/108) at 24 months. The overall rates of major morbidity and neurological mortality after 2 years were 1.5% (5/328) and 0.6% (2/328), respectively. CONCLUSION: Our results demonstrate high rates of complete long-term occlusion among patients treated with pipeline embolization device with shield technology. We also observed low rates of mortality and morbidity consistent with fewer thromboembolic complications with pipeline embolization devices with shield technology.

3.
Front Cell Dev Biol ; 12: 1365705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572484

RESUMO

The establishment of the embryonic dorsoventral axis in Xenopus occurs when the radial symmetry around the egg's animal-vegetal axis is broken to give rise to the typical symmetry of Bilaterians. We have previously shown that the Notch1 protein is ventrally enriched during early embryogenesis in Xenopus laevis and zebrafish and exerts ventralizing activity through ß-Catenin destabilization and the positive regulation of ventral center genes in X. laevis. These findings led us to further investigate when these asymmetries arise. In this work, we show that the asymmetrical distribution of Notch1 protein and mRNA precedes cortical rotation and even fertilization in X. laevis. Moreover, we found that in unfertilized eggs transcripts encoded by the ventralizing gene bmp4 are also asymmetrically distributed in the animal hemisphere and notch1 transcripts accumulate consistently on the same side of the eccentric maturation point. Strikingly, a Notch1 asymmetry orthogonal to the animal-vegetal axis appears during X. laevis oogenesis. Thus, we show for the first time a maternal bias in the distribution of molecules that are later involved in ventral patterning during embryonic axialization, strongly supporting the hypothesis of a dorsoventral prepattern or intrinsic bilaterality of Xenopus eggs before fertilization.

4.
Reumatol Clin (Engl Ed) ; 20(3): 136-141, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38443231

RESUMO

OBJECTIVES: When rheumatoid arthritis (RA) starts after the age of 60 it is called elderly-onset rheumatoid arthritis (EORA) and when it starts earlier, young-onset rheumatoid arthritis. (YORA). There are few Latin American studies that compared both groups. The objective of the study was to evaluate differences in the clinical characteristics, evolution and treatment among patients with RA with onset before or after 60 years of age. MATERIALS AND METHODS: Observational study of patients with RA attended consecutively in four centers in Argentina. Sociodemographic data, comorbidities, clinical manifestations at diagnosis, presence of rheumatoid factor and/or anti-CCP (cyclic citrullinated peptide) and treatments received were collected. At the last visit, swollen and tender joints, assessment of disease activity by the patient and physician, the presence of radiographic erosions, and functional status using the HAQ-DI were recorded. RESULTS: 51 patients from each group were analyzed. The EORA group had a significantly higher proportion of smokers (58.8% vs. 35.3%, p = 0.029), cardiovascular history (54.9% vs. 21.6%, p = 0.001), abrupt onset (49% vs. 29.4%, p = 0.034) or with symptoms similar to PMR (19.6% vs. 0%, p = 0.001). Lower methotrexate doses were used in the EORA group: 19 mg (15-25) vs. 21.9 mg (20-25) (p = 0.0036) and more frequently did not receive bDMARDs or tsDMARDs. DISCUSSION AND CONCLUSIONS: The benefits of intensive treatment in patients with RA have been described. In this study, the use of DMARDs in the EORA group was less intensive, suggesting that advanced age constitutes a barrier in the therapeutic choice.


Assuntos
Antirreumáticos , Artrite Reumatoide , Idoso , Humanos , Artrite Reumatoide/tratamento farmacológico , Fator Reumatoide , Metotrexato/uso terapêutico , Anticorpos Antiproteína Citrulinada , Antirreumáticos/uso terapêutico
5.
Rev. epidemiol. controle infecç ; 14(1): 75-83, jan.-mar. 2024. ilus
Artigo em Inglês | LILACS | ID: biblio-1567043

RESUMO

Background and Objectives: the present study was conducted in the city of Rivera, situated in northern Uruguay on the border with Brazil. The disease initially progressed slowly in 2020, with subsequent outbreaks followed by a rapid increase in incidence. The objective was to explore the relationship between the spatial distribution of COVID-19 cases in a binational city and variables such as socioeconomic status, population density, and mobility patterns, with the aim of informing public policies. Methods: an exploratory study was conducted between August 2020 and January 2021 using data obtained from the Ministry of Health. The explanatory variables considered included population density, socioeconomic level, and mobility. Three distinct periods from 2020 to 2021 were identified. Spatial autocorrelation was analyzed using Moran's Index and the Gi* statistic (Getis & Ord). Hierarchical cluster analysis was employed to identify homogeneous groups of census segments. Results: a total of 1,846 cases were georeferenced. Through hierarchical cluster analysis, seven homogeneous groups were identified. Mobility was found to explain the incidence of cases among the high socioeconomic level group, while population density accounted for the differences observed in the low socioeconomic group. Conclusion: in this city, priority should be given to populations residing in areas with higher population density and greater mobility. This small-scale territorial analysis provides valuable information for developing localized policies aimed at addressing health crises.(AU)


Justificación y Objetivos: el estudio se realizó en la ciudad de Rivera, situada en el norte del país en la frontera con Brasil. La enfermedad progresó lentamente durante 2020, con brotes posteriores seguidos de un rápido aumento de la incidencia. El objetivo fue explorar la relación entre la distribución espacial de los casos de COVID-19 en una ciudad binacional y variables como nivel socioeconómico, densidad poblacional y patrones de movilidad, con el objetivo de informar políticas públicas. Métodos: se realizó un estudio exploratorio entre agosto 2020 y enero 2021 con datos del Ministerio de Salud, considerando semanas epidemiológicas. Las variables explicativas consideradas fueron densidad poblacional, nivel socioeconómico y movilidad. Se identificaron tres periodos temporales desde agosto 2020 hasta enero 2021. Se analizo la autocorrelación espacial empleando el Índice de Moran y estadística Gi* (Getis & Ord). Mediante el análisis de cluster jerárquico, fue posible identificar grupos homogéneos de segmentos censales. Resultados: se georreferenciaron un total de 1.846 casos. Mediante análisis de cluster jerárquico, se identificaron siete grupos homogéneos. Para el nivel alto socioeconómico, la movilidad es el factor explicativo de una mayor incidencia de casos. Mientras que, para para el grupo de nivel bajo, la densidad de la población fue el factor explicativo de las diferencias en la presentación de la enfermedad. Conclusión: la población a ser priorizada en esta ciudad corresponde a aquellas zonas con mayor densidad poblacional y donde se incrementa la movilidad. El análisis territorial a pequeña escala genera información para la construcción de política local, ante una crisis sanitaria, que la hace más eficaz.(AU)


Justificativa e Objetivos: o presente estudo foi realizado na cidade de Rivera, localizada no norte do Uruguai, na fronteira com o Brasil. A doença progrediu lentamente durante 2020, com surtos subsequentes seguidos por um rápido aumento na incidência. O objetivo foi explorar a relação entre a distribuição espacial dos casos de COVID-19 em uma cidade binacional e variáveis como nível socioeconômico, densidade populacional e padrões de mobilidade, com o objetivo de informar políticas públicas. Métodos: estudo exploratório foi realizado entre agosto de 2020 e janeiro de 2021 com dados do Ministério da Saúde. As variáveis explicativas incluíram densidade populacional, nível socioeconômico e mobilidade. Três períodos distintos de 2020 a 2021 foram identificados. Autocorrelação espacial foi analisada com o Índice de Moran e a estatística Gi* (Getis & Ord). Utilizando a análise de cluster hierárquico, foi possível identificar grupos homogêneos de segmentos censitários. Resultados: um total de 1.846 casos foi georreferenciado. Através da análise de cluster hierárquico, sete grupos homogêneos foram identificados. A mobilidade foi encontrada como explicativa para a incidência de casos no grupo de alto nível socioeconômico, enquanto a densidade populacional explicou as diferenças observadas no grupo de baixo nível socioeconômico. Conclusão: nessa cidade, as populações a serem priorizadas são aquelas que residem em áreas com maior densidade populacional e maior mobilidade. Essa análise territorial em pequena escala fornece informações valiosas para o desenvolvimento de políticas locais destinadas a lidar com crises de saúde.(AU)


Assuntos
Classe Social , Mobilidade Social , Densidade Demográfica , Análise Espaço-Temporal , Fatores Sociais , COVID-19/epidemiologia
6.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1569801

RESUMO

Introducción: El cáncer de mama, según la Organización Mundial de la Salud, ha pasado a ser el más diagnosticado en el mundo, superando incluso al de pulmón. Cuba presenta altas tasas de incidencia y mortalidad de este tipo de cáncer. Para afrontar esta situación, su sistema público de salud ha implementado un programa nacional de detección precoz y tratamiento instaurado cuyo objetivo fundamental es lograr una mayor supervivencia de las pacientes. Objetivo: Determinar la supervivencia a los 5 años de las pacientes operadas de cáncer de mama en la provincia de Cienfuegos. Métodos: Se realizó un estudio de supervivencia a 5 años de los casos operados de cáncer de mama en el trienio 2013-2015, el cual se desarrolló mediante el método límite del producto de Kaplan-Meier a través del cálculo de supervivencia expuesto mediante tablas y gráficos. El universo estuvo constituido por todas las pacientes operadas en ese trienio. Las variables estudiadas fueron: edad, sexo, color de la piel, mama afectada, localización, tipo histológico, técnica quirúrgica, grado de reintegración social y estado a los 5 años de operadas. Resultados: Sobrevivieron más las pacientes de 50-70 años, con tumor en mama izquierda, localizado en cuadrante inferior interno, con tipo histológico carcinoma ductal infiltrante, y las que fueron objeto de mastectomías radicales. Conclusiones: El 77,3 % de los pacientes estudiados reportaron una supervivencia a los 5 años. Ese porcentaje es comparable al informado en los países altamente desarrollados. Este resultado se asocia mayormente al diagnóstico en etapas tempranas de la enfermedad y a la aplicación de la cirugía radical.


Introduction: Breast cancer, according to the World Health Organization, has become the most diagnosed cancer in the world, surpassing even lung cancer. Cuba has high incidence and mortality rates of this type of cancer. To address this situation, its public health system has implemented a national program for early detection and treatment whose main objective is to achieve greater survival of such patients. Objective: To determine the 5-year survival of patients operated on for breast cancer in the province of Cienfuegos. Methods: A study was carried out of the 5-year survival in patients operated on for breast cancer in the triennium 2013-2015, developed using the Kaplan-Meier product-limit method through calculation of survival exposed by means of tables and graphs. The universe was made up of all the patients operated on in that triennium. The variables studied were age, sex, skin color, affected breast, location, histological type, surgical technique, degree of social reintegration and status 5-years after surgery. Results: The highest survival was observed among the patients aged 50-70 years, with tumor in the left breast and located in the lower inner quadrant, of histological type of an infiltrating ductal carcinoma, and those who underwent radical mastectomies. Conclusions: 77.3% of the studied patients reported 5-year survival. This percentage is comparable to that reported in highly developed countries. This result is mostly associated to diagnosis in early stages of the disease and to the application of radical surgery.

7.
Medicina (B.Aires) ; 83(5): 705-718, dic. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1534874

RESUMO

Resumen Introducción : El inicio de la pandemia COVID-19, obligó a implementar cambios en el sistema de aten ción de los servicios de emergencia. Coincidentemente, en nuestra institución, implementamos el software de inteligencia artificial (IA), RAPID.AI, para el análisis de imágenes en el ataque cerebrovascular isquémico (ACVi). Nuestro objetivo fue evaluar el impacto del uso de la IA junto a los cambios en el triage durante la pandemia por COVID-19 en pacientes con ACVi por oclusión de gran vaso cerebral (OGVC). Métodos : Se crearon 2 grupos de pacientes con ACVi por OGVC tratados con terapia de reperfusión endovenosa más endovascular o terapia endovascu lar directa. Grupo 1: pacientes de enero 2019 a junio 2020; Grupo 2: pacientes de julio 2020 a diciembre de 2021, estudiados con RAPID.AI. Se analizaron datos clínicos, y métricas temporales. Se compararon según hora de arribo de 08:00 a 20:00 h (diurno) vs. 20:01 a 7:59 h (nocturno). Resultados : El grupo 1 comprendió 153 pacientes y el grupo 2 133. En el grupo 2 la métrica puerta-imagen y adquisición de la imagen fueron menores, con menor tiempo puerta-inicio de imagen y puerta-recanalización; los pacientes en horario nocturno presentaron mayor NIHSS y tiempos inicio-ingreso con menor proporción de independencia funcional a 90 días. Conclusiones : El uso de la IA para el análisis de imá genes junto a un menor tiempo puerta-fin de imagen, permitió acortar el intervalo hasta la punción inguinal. En el análisis por horarios durante la pandemia, los pacientes ingresados en horario diurno presentaron métricas puerta-imagen, tiempo de imagen y puerta-recanalización significativamente menores.


Abstract Introduction : The start of the COVID-19 pandemic forced the implementation of changes in the emergency services care system. Concomitantly, at our institution, we implemented the artificial intelligence (AI) software, RAPID.AI, for image analysis in ischemic stroke (IS). Our objective was to evaluate the impact of the use of AI together with the changes in the triage during the COVID-19 pandemic in patients with stroke due to large vessel occlusion (LVO). Methods : We included patients with IS due to LVO treated with intravenous reperfusion therapy plus en dovascular or direct endovascular therapy. Results : Two groups were created. Group 1: patients from January 2019 to June 2020; Group 2: patients from July 2020 to December 2021, studied with RAPID.AI. Clini cal data and temporal metrics were analyzed. They were compared according to arrival time from 08:00 to 20:00 (daytime) vs 20:01 to 7:59 (night). Results: We included 286 patients, 153 in group 1 and 133 in group 2. In group 2, door-image metric and image duration were lower, with shorter door-image onset and door-recanalization times; patients who arrived at night had higher NIHSS and longer time from onset-to-door with lower propor tion of functional independence at 90 days (mRS ≤ 2). Conclusions : The use of AI for image analysis along with a shorter door to end of image time allowed to reduce the interval to groin puncture. In the analysis by hours during the pandemic, patients admitted in daytime hours had significantly lower door to image, image time acquisition, and door to recanalization metrics.

8.
Medicina (B Aires) ; 83(5): 705-718, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37870328

RESUMO

INTRODUCTION: The start of the COVID-19 pandemic forced the implementation of changes in the emergency services care system. Concomitantly, at our institution, we implemented the artificial intelligence (AI) software, RAPID.AI, for image analysis in ischemic stroke (IS). Our objective was to evaluate the impact of the use of AI together with the changes in the triage during the COVID-19 pandemic in patients with stroke due to large vessel occlusion (LVO). METHODS: We included patients with IS due to LVO treated with intravenous reperfusion therapy plus endovascular or direct endovascular therapy. RESULTS: Two groups were created. Group 1: patients from January 2019 to June 2020; Group 2: patients from July 2020 to December 2021, studied with RAPID.AI. Clinical data and temporal metrics were analyzed. They were compared according to arrival time from 08:00 to 20:00 (daytime) vs 20:01 to 7:59 (night). RESULTS: We included 286 patients, 153 in group 1 and 133 in group 2. In group 2, door-image metric and image duration were lower, with shorter door-image onset and door-recanalization times; patients who arrived at night had higher NIHSS and longer time from onset-to-door with lower proportion of functional independence at 90 days (mRS = 2). CONCLUSIONS: The use of AI for image analysis along with a shorter door to end of image time allowed to reduce the interval to groin puncture. In the analysis by hours during the pandemic, patients admitted in daytime hours had significantly lower door to image, image time acquisition, and door to recanalization metrics.


Introducción: El inicio de la pandemia COVID-19, obligó a implementar cambios en el sistema de atención de los servicios de emergencia. Coincidentemente, en nuestra institución, implementamos el software de inteligencia artificial (IA), RAPID.AI, para el análisis de imágenes en el ataque cerebrovascular isquémico (ACVi). Nuestro objetivo fue evaluar el impacto del uso de la IA junto a los cambios en el triage durante la pandemia por COVID-19 en pacientes con ACVi por oclusión de gran vaso cerebral (OGVC). Métodos: Se crearon 2 grupos de pacientes con ACVi por OGVC tratados con terapia de reperfusión endovenosa más endovascular o terapia endovascular directa. Grupo 1: pacientes de enero 2019 a junio 2020; Grupo 2: pacientes de julio 2020 a diciembre de 2021, estudiados con RAPID.AI. Se analizaron datos clínicos, y métricas temporales. Se compararon según hora de arribo de 08:00 a 20:00 h (diurno) vs. 20:01 a 7:59 h (nocturno). Resultados: El grupo 1 comprendió 153 pacientes y el grupo 2 133. En el grupo 2 la métrica puerta-imagen y adquisición de la imagen fueron menores, con menor tiempo puerta-inicio de imagen y puerta-recanalización; los pacientes en horario nocturno presentaron mayor NIHSS y tiempos inicio-ingreso con menor proporción de independencia funcional a 90 días. Conclusiones: El uso de la IA para el análisis de imágenes junto a un menor tiempo puerta-fin de imagen, permitió acortar el intervalo hasta la punción inguinal. En el análisis por horarios durante la pandemia, los pacientes ingresados en horario diurno presentaron métricas puerta-imagen, tiempo de imagen y puertarecanalización significativamente menores.


Assuntos
Isquemia Encefálica , COVID-19 , Acidente Vascular Cerebral , Humanos , Pandemias , Trombectomia/métodos , Inteligência Artificial , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento , Tempo para o Tratamento , Isquemia Encefálica/terapia , Estudos Retrospectivos
9.
Medisur ; 21(1)feb. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1440634

RESUMO

La investigación final que deben realizar los residentes para culminar la especialización es el instrumento creado en el proceso formativo de posgrado, para que aprenda y aplique los aspectos básicos de la metodología de la investigación médica. Este trabajo tiene como objetivo brindar una guía de consulta a estudiantes y docentes, sobre la estructura y presentación de los proyectos de investigación e informe final de los trabajos de terminación de la especialidad. Para ello se realizó una búsqueda bibliográfica para la recopilación y clasificación de la bibliografía actualizada. Se brindan consideraciones de cómo elaborar el proyecto de investigación y el informe final y se especifica la información que deben tener ambos documentos. Se exponen elementos fundamentales sobre la estructura y presentación de los proyectos de investigación e informe final que podrán ser utilizados como guía de consulta para estudiantes y docentes.


The final research that residents must carry out to complete the specialization is the instrument created in the postgraduate training process, so that they learn and apply the basic aspects of medical research methodology. This work aims to provide a reference guide for students and teachers, on the structure and presentation of research projects and final report of completion of the specialty. For this, a bibliographic search was carried out for the compilation and classification of the updated bibliography. Considerations of how to prepare the research project and the final report are provided, and the information that both documents must have is specified. Fundamental elements on the structure and presentation of research projects and final report that can be used as a reference guide for students and teachers are exposed.

10.
Dalton Trans ; 52(6): 1623-1641, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36648116

RESUMO

Chagas' disease (American Trypanosomiasis) is an ancient and endemic illness in Latin America caused by the protozoan parasite Trypanosoma cruzi. Although there is an urgent need for more efficient and less toxic chemotherapeutics, no new drugs to treat this disease have entered the clinic in the last decades. Searching for metal-based prospective antichagasic drugs, in this work, multifunctional Re(I) tricarbonyl compounds bearing two different bioactive ligands were designed: a polypyridyl NN derivative of 1,10-phenanthroline and a monodentate azole (Clotrimazole CTZ or Ketoconazol KTZ). Five fac-[Re(CO)3(NN)(CTZ)](PF6) compounds and a fac-[Re(CO)3(NN)(KTZ)](PF6) were synthesized and fully characterized. They showed activity against epimastigotes (IC50 3.48-9.42 µM) and trypomastigotes of T. cruzi (IC50 0.61-2.79 µM) and moderate to good selectivity towards the parasite compared to the VERO mammalian cell model. In order to unravel the mechanism of action of our compounds, two potential targets were experimentally and theoretically studied, namely DNA and one of the enzymes involved in the parasite ergosterol biosynthetic pathway, CYP51 (lanosterol 14-α-demethylase). As hypothesized, the multifunctional compounds shared in vitro a similar mode of action as that disclosed for the single bioactive moieties included in the new chemical entities. Additionally, two relevant physicochemical properties of biological interest in prospective drug development, namely lipophilicity and stability in solution in different media, were determined. The whole set of results demonstrates the potentiality of these Re(I) tricarbonyls as promising candidates for further antitrypanosomal drug development.


Assuntos
Antiprotozoários , Doença de Chagas , Compostos Organometálicos , Trypanosoma cruzi , Humanos , Doença de Chagas/tratamento farmacológico , Compostos Organometálicos/química , Antiprotozoários/química , Cetoconazol/química
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