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Abstract Total Hip Arthroplasty (THA) is one of the surgical procedures carried out satisfactorily in procedures for osteoarthritis and trauma lesions. ATC surgery reduces pain and improves the quality of life of young patients. Therefore, it is of great importance to improve the properties of hip implants, since current implants do not match their lifespan with the life expectancy of a young patient. This is because the solid prostheses that currently exist have a higher Young's modulus, and therefore are too rigid compared to the bone tissue. On the other hand, the cyclic and continuous loads to which the hip joint is subjected in daily activities, can cause loosening and consequent implant loss The present work proposes an implant manufactured with a porous lattice structure, which aims to reduce stiffness, allow bone growth and a more effective mechanical load transfer. Three computational models subjected to static charges were evaluated and compared: 1) healthy femur, 2) implanted femur with a commercial prosthesis, and 3) implanted femur with a prosthesis with lattice structure. For the computational analysis it was decided to perform a static analysis of a person standing on the left foot; a load equivalent to the body weight was applied on the head of the femur, balancing the reaction forces in the system of forces (contact force, body weight, and abductor muscle).. The results were shown in terms of displacement, compression and deformation. The model implanted with a prosthesis with a lattice design presented a slight decrease in displacement, and a decrease in compression and deformation values, which indicated that the proposed design has a better distribution and transport of the loads through its structure.

Resumen La artroplastia total de cadera (ATC) es uno de los tratamientos quirúrgicos llevados a cabo de manera satisfactoria en procedimientos para la osteoartritis y lesiones de trauma. La ATC reduce el dolor y mejora la calidad de vida de los pacientes. Por lo tanto, es de gran importancia mejorar las propiedades de los implantes de cadera, ya que los implantes actuales tienen un tiempo de vida útil y deben cumplir con las expectativas de rehabilitación para los pacientes. Esto se debe a que las prótesis sólidas que existen actualmente tienen un módulo de Young más elevado, y por lo tanto son demasiado rígidas a comparación del tejido óseo. Por otro lado, las cargas cíclicas y continuas a las que se ve sometida la articulación de la cadera en actividades diarias, pueden ser causa del aflojamiento y consecuente pérdida del implante. El presente trabajo propone un implante fabricado con una estructura porosa tipo látice, el cual tiene como objetivos reducir la rigidez, permitir crecimiento óseo y una transferencia de cargas mecánicas más efectiva. Se evaluaron y compararon tres modelos computacionales sometidos a cargas estáticas: 1) fémur sano, 2) fémur implantado con una prótesis comercial, y 3) fémur implantado con una prótesis con estructura látice. Para el modelo computacional se optó por hacer un análisis estático de una persona parada sobre el pie izquierdo; donde se aplicó una carga equivalente del peso corporal sobre la cabeza del fémur, equilibrando las fuerzas de reacción en el sistema de fuerzas (fuerza de contacto, peso corporal, y músculo abductor). Los resultados fueron mostrados en términos de desplazamiento, compresión y deformación. El modelo implantado con una prótesis con un diseño tipo látice presentó una ligera disminución de desplazamiento, y disminución en los valores de compresión y deformación, lo que indicó que el diseño propuesto posee una mejor distribución y transporte de las cargas a través de su estructura.

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Resumen Las amputaciones de extremidades superiores pueden producir diversos grados de incapacidad en la persona afectada, esto es exacerbado aún más, si se presenta durante un periodo de su vida laboral activa, por esta razón es de importancia social el estudio de las prótesis y algoritmos que ayuden a un mejor control de estas por parte del usuario. En esta investigación, se propone una arquitectura basada en redes neuronales recurrentes del tipo Long Short-Term Memory y redes convolucionales para la clasificación de señales electromiográficas, con aplicaciones para control de prótesis de mano. La red propuesta clasifica tres tipos de agarres realizados con la mano: cilíndrico, esférico y de gancho. El modelo propuesto al ser evaluado mostró una eficiencia (accuracy) del 89 %, en contraste con una red neuronal artificial basada en capas completamente conectadas que solo obtuvo una eficiencia del 80% en la predicción de los agarres. El presente trabajo se limita solamente a evaluar la red ante una entrada de electromiograma y no se implementó un sistema de control para la prótesis de la mano. Así, una arquitectura de redes convolucionales para el control de prótesis de mano que pueden ser entrenadas con las señales del sujeto.

Abstract Upper extremities amputations can produce different disability degrees in the amputated person, this is acerbated even more, when it happens during active working life. So, for this reason, it is of social importance the study of prostheses and algorithms that help a better control of these by the user. In this research, we propose an architecture based on recurrent neural networks, called Long Short-Term Memory, and convolutional neural networks for classification of electromyographic signals, with applications for hand prosthesis control. The proposed network classifies three types of movements made by the hand: cylindrical, spherical and hook grips. The proposed model showed an efficiency (accuracy) of 89%, in contrast to an artificial neural network based on completely connected layers that only obtained an efficiency of 80% in the prediction of the hand movements. The present work is limited to evaluate the network with an electromyogram input, the control system for hand prosthesis was not implemented. Thus, an architecture of convolutional networks for the control of hand prostheses that can be trained with the signals of the subject.

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Background The aim of this study was to analyse ideas regarding pre-exposure prophylaxis (PrEP) for the prevention of HIV among groups of men who have sex with men in Mexico for future implementation in health services. METHODS: During 2015, 54 people participated in four focus groups in three Mexican cities. Issues related to challenges for uses and limitations of PrEP were explored. RESULTS: In contrast with other qualitative studies, which emphasised problems with relationships with other people for PrEP use or access to key populations, Mexican participants focused their concerns around the public health services organisation: PrEP is too expensive and the health services have no resources, which will affect services and result in discrimination. Participants identified possible stigmatisation related to prejudices of medical providers who do not approve the decreased use of condoms. As a potential solution, participants suggested that the Mexican Government could negotiate a lower cost for PrEP and public health services could provide the medication, with periodical review of the arrangements by civil organisations. CONCLUSION: In the current context of the new Mexican government, it is necessary to propose public politics focused on negotiating with pharmaceutical companies on the costs of the PrEP, coordinating public services with groups within civil society and strengthening policies and actions to reduce stigma and discrimination.

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OBJECTIVE: Health policies in Latin America are centered on the democratization of health. Since 2003, during the last generation of reforms, health systems in this region have promoted governance strategies for better agreements between governments, institutions, and civil society. In this context, we develop an evaluative research to identify trends and evidence of governance after health care reforms in six regions of Mexico. METHODS: Evaluative research was developed with a retrospective design based on qualitative analysis. Primary data were obtained from 189 semi-structured interviews with purposively selected health care professionals and key informants. Secondary data were extracted from a selection of 95 official documents on results of the reform project at the national level, national health policies, and lines of action for good governance. Data processing and analysis were performed using ATLAS.ti and PolicyMaker. RESULTS: A list of main strengths and weaknesses is presented as evidence of health system governance. Accountability at the federal level remains prescriptive; in the regions, a system of accountability and transparency in the allocation of resources and in terms of health democratization strategies is still absent. CONCLUSION: Social protection and decentralization schemes are strategies that have allowed for improvements with a proactive role of users and civil society. Regarding challenges, there are still low levels of governance and difficulties in the effective conduct of programs and reform strategies together with a lack of precision in the rules and roles of the different actors of the health system.

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Structural characteristics of discharged and undischarged nematocysts from the hydrozoans Millepora alcicornis and Millepora complanata, two fire corals collected in the Mexican Caribbean, were examined using transmission electron, scanning and light microscopy. In this study, we report for the first time images of the nematocysts found in these Mexican Caribbean venomous species. Two types of nematocysts were observed in both species, the more abundant identified as macrobasic mastigophore and the other a stenotele type. Macrobasic mastigophores were present in medium and large size classes while stenoteles appeared in only one size.

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Structural characteristics of discharged and undischarged nematocysts from the hydrozoans Millepora alcicornis and Millepora complanata, two fire corals collected in the Mexican Caribbean, were examined using transmission electron, scanning and light microscopy. In this study, we report for the first time images of the nematocysts found in these Mexican Caribbean venomous species. Two types of nematocysts were observed in both species, the more abundant identified as macrobasic mastigophore and the other a stenotele type. Macrobasic mastigophores were present in medium and large size classes while stenoteles appeared in only one size.(AU)

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El diagnóstico del síndrome de apnea obstructiva del sueño (SAOS) se realiza con el polisomnograma de sueño, examen de considerable costo económico para el paciente. Se han diseñado algunas herramientas, como el score de Epworth, con el fin de predecir si un paciente tiene o no un SAOS. Se pretende investigar si existen diferencias entre pacientes roncadores y pacientes con SAOS que permitan al clínico establecer el diagnóstico y severidad del SAOS con mayor certeza previo al polisomnograma de sueño. Además, evaluar el valor predictivo del score de Epworth. Para ello se efectuó un estudio retrospectivo de fichas clínicas y polisomnogramas de sueño en 220 pacientes roncadores. El presente estudio encontró que la edad fue el único parámetro distinto estadísticamente significativo entre roncadores y SAOS, siendo estos últimos poseedores de una mayor edad. No hubo diferencias en patologías asociadas, consumo de medicamentos, score de Epworth, examen otorrinolaringológico e índice de masa corporal (IMC). En pacientes con SAOS se observó que, a mayor IMC existía un mayor nivel de desaturación de oxígeno nocturno. El score de Epworth tuvo un valor predictivo positivo (VPP) de 88,4 por ciento, y un valor predictivo negativo (VPN) de 20 por ciento. Se concluye que no es posible predecir clínicamente si un paciente es portador de un SAOS.

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OBJECTIVE: To determine the costs of health services and the financial consequences of changes in the epidemiological profile of chronic diseases in Latin America. STUDY DESIGN: We conducted longitudinal analyses of costs and of the economic impact of the epidemiological transition in healthcare services for diabetes and hypertension in the Mexican health system. The study population included both the insured and uninsured populations. METHODS: The cost-evaluation method was based on the instrumentation and consensus techniques. To estimate the epidemiological changes and financial consequences for 2004-2006, six models were constructed according to the Box-Jenkins technique, using confidence intervals of 95% and the Box-Pierce test. FINDINGS: Costs ranged from US$613 to US$887 for diabetes, and from US$485 to US$622 for hypertension. Regarding epidemiological changes for 2004 compared with 2006, an increase is expected in both cases, although results predict a greater increase for diabetes, 10-15% in all three institutions (P<0.05). Comparing the financial consequences of health services required by insured and uninsured populations, the greater increase (17%) will be for the insured population (P<0.05). The financial requirements for both diseases will amount to 9.5% of the total budget for the uninsured population and 13.5% for the insured population. CONCLUSIONS: If the risk factors and the different healthcare models remain as they are at present, the economic impact of expected epidemiological changes on the social security system will be particularly strong. Another relevant financial factor is the appearance of internal competition in the use and allocation of financial resources among the main providers in the health services; this factor becomes even more complicated within each provider. In effect, within each institution, hypertension and diabetes programmes must compete for resources with other programmes for chronic and infectious diseases.

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An evaluative study with a cross-sectional design was carried out on healthcare cost indicators reported by the 2000 National Health Survey in Mexico, to determine which population group had higher health costs/expenditures in relation to family income. The results suggest that in middle-income countries such as Mexico, families with lower incomes tend to pay more for healthcare services.

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La enfermedad de von Willebrand (EVW) es la coagulopatía más frecuente en niños. Una de las principales complicaciones de la adenoamigdalectomía es la hemorragia. Debido a su patología de base, representan un gran desafío aquellos pacientes con EVW a quienes se efectúa esta cirugía. Desde hace algunos años, se utiliza desmopresina (DDAVP) para el manejo de esta patología. Se estudiaron restrospectivamente 15 pacientes pediátricos portadores de EVW tipo I, adenoamigdalectomizados en el Hospital Clínico de la Pontificia Universidad Católica de Chile. Todos fueron hospitalizados y, previa medición del Factor VIII plasmático, se les proporcionó DDAVP. Una hora después de iniciada la infusión, se controló este factor. Si se incrementaba en 50 por ciento del valor basal, la cirugía se efectuaba sin aporte de hemoderivados; de lo contrario, se indicaba crioprecipitado. En ambos casos se utilizó ácido tranexámico como coadyuvante.La respuesta a DDAVP fue positiva en 13 pacientes (87 por ciento). En los 2 pacientes en quienes ésta no se observó se les suministró crioprecipitado. Todo el grupo estudiado evolucionó satisfactoriamente. No fue necesario utilizar crioprecipitado de apoyo o cirugías de revisión. Se concluye que DDAVP evita el uso de hemoderivados en la mayoría de los pacientes con EVW tipo I sometidos a adenoamigdalectomía, no posee efectos adversos relevantes y no aumenta los costos de la cirugía.

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Los tumores amigdalinos abarcan una diversidad de lesiones, tanto neoplásicas como inflamatorias. En pacientes adultos, las neoplasias corresponden principalmente a patología maligna, en su mayoría carcinoma epidermoide. El objetivo del presente trabajo es describir el perfil epidemiológico de los pacientes portadores de tumor amigdalino, y analizar los principales hallazgos histopatológicos de los diferentes tipos tumorales. Se efectúa un estudio retrospectivo descriptivo de pacientes adultos evaluados por tumor amigdalino en el Hóspital Dr. Sotero del Río entre los años 1998 y 2004. Se analizaron las fichas de 19 pacientes. La edad promedio fue de 50 años, con un ligero predominio del sexo masculino. Un 57,9 por ciento de los pacientes refería odinofagia y todos presentaban, al examen físico, una asimetría amigdalina. El hallazgo histopatológico más frecuente fue el carcinoma epidermoide (31,6 por ciento), seguido por la hiperplasia folicular y parafolicular (26,3 por ciento), linfomas (10,5 por ciento) y papilomas (10,5 por ciento).

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Nuestro objetivo fue estudiar las características clínicas de pacientes de Trastorno Funcional Doloroso Temporomandibular (TFDT) y su asociación a otalgia refleja como forma de presentación. Se diseñó un estudio retrospectivo descriptivo de pacientes que consultaron al policlínico de cirugía maxilofacial entre enero 2002 y enero 2003. Se registraron variables demográficas y clínicas, siendo analizadas con estadística descriptiva. En el período descrito consultaron 255 pacientes, en 58 de ellos se diagnosticó TFDT, siendo éste nuestro grupo de estudio. La edad promedio fue de 45 años y la distribución por sexo fue de 50 pacientes de sexo femenino (86 por ciento) y 8, masculino (14 por ciento). En 47 por ciento de los casos el motivo de consulta fue otalgia. De ellos, el 88 por ciento fueron derivados por otorrinolaringólogo.

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Fiebre peródica, estomatitis aftosa, faringitis y adenopatía cervical (Síndrome PFAPA) es una entidad crónica y esporádica caracterizada por apisodios peiódicos de fiebre elevada de duración entre 3 a 6 días y recurrencia cada 3 a 8 semanas, acompañada por estomatitis aftosa, faringitis y adenitis cervicales. Los pacientes son sanos entre los episodios. Reportamos dos pacientes con los síntomas habituales del síndrome. La edad de comienzo de su enfermedad fue antes del año de vida y fueron tratados previamente a su diagnóstico con variados esquemas antimicrobianos sin respuesta clínica favorable. Posteriormente al diagnóstico de síndrome PFAPA, un paciente fue tratado con prednisona y evolucionó con rápida resolución de fiebre y el segundo ha recibido paracetamol e ibuprofeno con lenta mejoría de su sintomatología. Ambos niños evolucionaron asintomáticos entre los episodios febriles y con desarrollo normal. El conocimiento de este síndrome podría ayudar a un diagnóstico precoz y a un manejo adecuado de las alternativas terapéuticas.

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This article presents the results from an evaluative longitudinal study with before-after design. The main objective was to determine the effects of health care decentralization on changes in health financing. Taking into account feasibility, political and technical criteria, three Latin American countries were selected as study populations: Mexico, Nicaragua and Peru. The methodology had two main phases. In the first phase, the study referred to secondary sources of data and documents to obtain information about the following variables: type of decentralization implemented, source of finance, funds of financing, providers, final use of resources and mechanisms for resource allocation. In the second phase, the study referred to primary data collected in a survey of key personnel from the health sectors of each country. Taking into account the changes implemented in the three countries, as well as the strengths and weaknesses of each country in financing and decentralization, a rule for decision-making is proposed that attempts to identify the main financial changes implemented in each country and the basic indicators that can be used in future years to direct the planning, assessment, adjustment and correction of health financing and decentralization.

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This paper identifies the trends and recent progress in the generation and reproduction of knowledge on health economic evaluation. Analysis is organized along nine public health action fields, namely: health determinants and predictors, economic value of health, healthcare demand, healthcare supply, microeconomic evaluation of healthcare, healthcare market balance, evaluation of policy instruments, general evaluation of the health system, and healthcare planning, regulation and supervision. Each action field is defined to place the reader in the proper setting and level of analysis. In addition, thematic research topics developed in each action field are proposed and discussed. The generation and reproduction of knowledge on the different action fields was based on the review of the bibliographic databases MEDLINE and LILACS for the 1992-2000 period. Results lead to the conclusion that development and application of economic evaluation of healthcare has been uneven across different countries and that there is a growing increase of applications starting in 1994, the year of initiation of healthcare reform in Latin America.

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