Patient-specific multi-physics simulations of fibrotic changes in left atrial tissue mechanics impact on hemodynamics.

Stroke is a leading cause of death and disability worldwide. Atrial myopathy, including fibrosis, is associated with an increased risk of ischemic stroke, but the mechanisms underlying this association are poorly understood. Fibrosis modifies myocardial structure, impairing electrical propagation and tissue biomechanics, and creating stagnant flow regions where clots could form. Fibrosis can be mapped non-invasively using late gadolinium enhancement magnetic resonance imaging (LGE-MRI). However, fibrosis maps are not currently incorporated into stroke risk calculations or computational electro-mechano-fluidic models. We present multi-physics simulations of left atrial (LA) myocardial motion and hemodynamics using patient-specific anatomies and fibrotic maps from LGE-MRI. We modify tissue stiffness and active tension generation in fibrotic regions and investigate how these changes affect LA flow for different fibrotic burdens. We find that fibrotic regions and, to a lesser extent, non-fibrotic regions experience reduced myocardial strain, resulting in decreased LA emptying fraction consistent with clinical observations. Both fibrotic tissue stiffening and hypocontractility independently reduce LA function, but together, these two alterations cause more pronounced effects than either one alone. Fibrosis significantly alters flow patterns throughout the atrial chamber, and particularly, the filling and emptying jets of the left atrial appendage (LAA). The effects of fibrosis in LA flow are largely captured by the concomitant changes in LA emptying fraction except inside the LAA, where a multi-factorial behavior is observed. This work illustrates how high-fidelity, multi-physics models can be used to study thrombogenesis mechanisms in a patient-specific manner, shedding light onto the link between atrial fibrosis and ischemic stroke. Key points: Left atrial (LA) fibrosis is associated with arrhythmogenesis and increased risk of ischemic stroke; its extent and pattern can be quantified on a patient-specific basis using late gadolinium enhancement magnetic resonance imaging.Current stroke risk prediction tools have limited personalization, and their accuracy could be improvedfib by incorporating patient-specific information like fibrotic maps and hemodynamic patterns.We present the first electro-mechano-fluidic multi-physics computational simulations of LA flow, including fibrosis and anatomies from medical imaging.Mechanical changes in fibrotic tissue impair global LA motion, decreasing LA and left atrial appendage (LAA) emptying fractions, especially in subjects with higher fibrosis burdens.Fibrotic-mediated LA motion impairment alters LA and LAA flow near the endocardium and the whole cavity, ultimately leading to more stagnant blood regions in the LAA.

The Effect of Ti/Ta Ratio and Processing Routes on the Hardness and Elastic Modulus of Porous TiNbZrTa Alloys.

TiNbZrTa alloys are promising for multidisciplinary applications, such as refractory and biomedical purposes, due to their high thermal stability and non-toxicity. Hardness and elastic modulus are among the key features for their adequate industrial applications. The influence of porosity and Ti/Ta ratio were investigated on TiNbZrTa alloys produced by three different processing routes, i.e., (i) blend element and posterior press and sintering (BE + P&S); (ii) mechanical alloying with press and sintering (MA + P&S); and (iii) arc melting and casting. Porosity decreased in the following order: casting < MA + P&S < BE + P&S. The total porosity of alloys increased with increasing Ta contents, i.e., by lowering the Ti/Ta ratio. However, the Ti/Ta ratio did not considerably affect the bonding energy or the elastic modulus. Hardness was increased significantly in dense alloys compared to porous ones. However, porosity and Ti/Ta ratio did not show a clear trend in hardness among the porous alloys.

Pulmonary vein flow split effects in patient-specific simulations of left atrial flow.

Disruptions to left atrial (LA) blood flow, such as those caused by atrial fibrillation (AF), can lead to thrombosis in the left atrial appendage (LAA) and an increased risk of systemic embolism. LA hemodynamics are influenced by various factors, including LA anatomy and function, and pulmonary vein (PV) inflow conditions. In particular, the PV flow split can vary significantly among and within patients depending on multiple factors. In this study, we investigated how changes in PV flow split affect LA flow transport, focusing for the first time on blood stasis in the LAA, using a high-fidelity patient-specific computational fluid dynamics (CFD) model. We use an Immersed Boundary Method, simulating the flow in a fixed, uniform Cartesian mesh and imposing the movement of the LA walls with a moving Lagrangian mesh generated from 4D Computerized Tomography images. We analyzed LA anatomies from eight patients with varying atrial function, including three with AF and either a LAA thrombus or a history of Transient Ischemic Attacks (TIAs). Using four different flow splits (60/40% and 55/45% through right and left PVs, even flow rate, and same velocity through each PV), we found that flow patterns are sensitive to PV flow split variations, particularly in planes parallel to the mitral valve. Changes in PV flow split also had a significant impact on blood stasis and could contribute to increased risk for thrombosis inside the LAA, particularly in patients with AF and previous LAA thrombus or a history of TIAs. Our study highlights the importance of considering patient-specific PV flow split variations when assessing LA hemodynamics and identifying patients at increased risk for thrombosis and stroke. This knowledge is relevant to planning clinical procedures such as AF ablation or the implementation of LAA occluders.

Survey data of Entrepreneurial intention and perceived social support from academics-scientists at Chilean Universities.

The data comes from a survey applied to 1027 scientists working in Chile. The survey was originally distributed to 5571 scientists. The research was carried out with the purpose of explaining the Entrepreneurial intention of the scientists. The survey consisted of 35 items in total, structured in five sections: (a) academic background and previous entrepreneurship (14 items), (b) Entrepreneurial intention (6 items), (c) Attitude towards entrepreneurship (5 items), (d) subjective social perception of support towards Entrepreneurship (3 items) and Control of Perceived Behavior towards Entrepreneurship (6 items). The data are linked to the theoretical model proposed in Acuña_Duran, Oyanedel y Pradenas-Wilson (2021).

Non-Newtonian blood rheology impacts left atrial stasis in patient-specific simulations.

The lack of mechanically effective contraction of the left atrium (LA) during atrial fibrillation (AF) disturbs blood flow, increasing the risk of thrombosis and ischemic stroke. Thrombosis is most likely in the left atrial appendage (LAA), a small narrow sac where blood is prone to stagnate. Slow flow promotes the formation of erythrocyte aggregates in the LAA, also known as rouleaux, causing viscosity gradients that are usually disregarded in patient-specific simulations. To evaluate these non-Newtonian effects, we built atrial models derived from 4D computed tomography scans of patients and carried out computational fluid dynamics simulations using the Carreau-Yasuda constitutive relation. We examined six patients, three of whom had AF and LAA thrombosis or a history of transient ischemic attacks (TIAs). We modeled the effects of hematocrit and rouleaux formation kinetics by varying the parameterization of the Carreau-Yasuda relation and modulating non-Newtonian viscosity changes based on residence time. Comparing non-Newtonian and Newtonian simulations indicates that slow flow in the LAA increases blood viscosity, altering secondary swirling flows and intensifying blood stasis. While some of these effects are subtle when examined using instantaneous metrics like shear rate or kinetic energy, they are manifested in the blood residence time, which accumulates over multiple heartbeats. Our data also reveal that LAA blood stasis worsens when hematocrit increases, offering a potential new mechanism for the clinically reported correlation between hematocrit and stroke incidence. In summary, we submit that hematocrit-dependent non-Newtonian blood rheology should be considered when calculating patient-specific blood stasis indices by computational fluid dynamics.

Análisis descriptivo de los trastornos psiquiátricos severos, en niños, niñas y jóvenes atendidos por equipo multidisciplinario DIAGNOSIS(1), entre enero de 2016 y enero de 2018 / Descriptive analysis of severe psychiatric disorders, in children and youth cared for by a multidisciplinary team DIAGNOSIS(1), between january 2016 and january 2018

OBJETIVO: Describir y analizar las características sociodemográficas y clínicas niños(as) y jóvenes con trastornos psiquiátricos severos, atendidos por equipo multidisciplinario DIAGNOSIS, en clínica privada de Santiago, desde enero de 2016 hasta enero de 2018.MÉTODO: estudio descriptivo, exploratorio, con análisis estadístico de características sociodemográficas y clínicas obtenidas de las fichas clínicas de los usuarios(as). RESULTADOS: muestra de 57 usuarios(as), el 69% se encuentra entre los 12 y 18 años. El principal motivo de ingreso es síndrome suicidal, seguido de agitación psicomotora. El diagnóstico principal al alta es trastorno del ánimo, seguido por trastornos psicóticos. En el eje II organización limítrofe de la personalidad, y coeficiente intelectual promedio. El promedio de hospitalización es de 39 días. DISCUSIÓN: se comparan los resultados con el estudio de Barker et al (2020) realizado con pacientes hospitalizados en una unidad de psiquiatría infanto-juvenil pública, los que resultan similares.

OBJECTIVE: Describe and analyze the sociodemographic and clinical characteristics of children and young people with severe psychiatric disorders, attended by a multidisciplinary DIAGNOSIS team, in a private clinic in Santiago, from January 2016 to January 2018. METHOD: descriptive, exploratory study, with statistical analysis of users' clinical records. RESULTS: sample of 57 users, 69% are between 12 and 18 years old. The main reason for admission is suicidal syndrome, followed by psychomotor agitation. The main diagnosis at discharge is mood disorder, followed by psychotic disorders. On axis II, the borderline organization of the personality, and the average IQ. The average hospital stay is 39 days.DISCUSSION: the results are compared with the study by Barker et al (2020) carried out with patients hospitalized in a public child and adolescent psychiatry unit, which are similar.

Entrepreneurial Intention and Perceived Social Support From Academics-Scientists at Chilean Universities.

Within Ajzen's Planned Behavior Theory framework, this article tests a model to estimate the predictors of entrepreneurial intention in academic scientists working in Chile. We adapted into Spanish the entrepreneurship intention questionnaire. We tested the entrepreneurship intention model on a sample of 1,027 scientists leading research projects funded by the Chilean Scientific and Technological Development Fund (FONDECYT), the country's primary scientific research grant. The results show strong empirical support for the entrepreneurship intention model proposed while highlighting some critical issues specific to entrepreneurial intention in scientists. In particular, we found an indirect effect of perceived subjective social support on entrepreneurial intention, which is mediated by entrepreneurial attitude and perceived behavioral control toward entrepreneurship. These results suggest that policies orientated toward promoting academic entrepreneurship should include developing a healthy social environment toward it, meaning that entrepreneurial intention is not only an individual but an organizational challenge. These policies should analyze the social norms guiding the scientists' reference groups to increase their effectiveness.

Diagnostic slippage: Medical uncertainty and engaged patienthood in the case of atypical disorders.

This study explores how patients affected by depersonalization/derealization disorder confront clinical uncertainty by investing in their own diagnosis and prognosis. While depersonalization/derealization has been a legitimate medical category within psychiatric nomenclature for decades, those affected by this condition have traditionally embarked on a diagnostic odyssey. As a rare disorder, clinicians have repeatedly misdiagnosed depersonalization/derealization as a byproduct of illnesses such as anxiety disorder, depression, or schizophrenia. Drawing from in-depth interviews, as well the analysis of videos and online posts, I explore the trajectory through which patients affected by depersonalization/derealization, dissatisfied with traditional diagnostic routes, have transformed the process of diagnostic revelation from a clinical prerogative to a lay accomplishment. This study indicates that a multifaceted process, consisting of a dialectical relation between the material reality of information democratization and a heightening cultural orientation towards engaged patienthood, may shorten diagnostic odysseys for people affected by atypical disorders and undermine physicians' authority to diagnose.

Demonstration of Patient-Specific Simulations to Assess Left Atrial Appendage Thrombogenesis Risk.

Atrial fibrillation (AF) alters left atrial (LA) hemodynamics, which can lead to thrombosis in the left atrial appendage (LAA), systemic embolism and stroke. A personalized risk-stratification of AF patients for stroke would permit improved balancing of preventive anticoagulation therapies against bleeding risk. We investigated how LA anatomy and function impact LA and LAA hemodynamics, and explored whether patient-specific analysis by computational fluid dynamics (CFD) can predict the risk of LAA thrombosis. We analyzed 4D-CT acquisitions of LA wall motion with an in-house immersed-boundary CFD solver. We considered six patients with diverse atrial function, three with either a LAA thrombus (removed digitally before running the simulations) or a history of transient ischemic attacks (LAAT/TIA-pos), and three without a LAA thrombus or TIA (LAAT/TIA-neg). We found that blood inside the left atrial appendage of LAAT/TIA-pos patients had marked alterations in residence time and kinetic energy when compared with LAAT/TIA-neg patients. In addition, we showed how the LA conduit, reservoir and booster functions distinctly affect LA and LAA hemodynamics. Finally, fixed-wall and moving-wall simulations produced different LA hemodynamics and residence time predictions for each patient. Consequently, fixed-wall simulations risk-stratified our small cohort for LAA thrombosis worse than moving-wall simulations, particularly patients with intermediate LAA residence time. Overall, these results suggest that both wall kinetics and LAA morphology contribute to LAA blood stasis and thrombosis.

Exosomes released upon mitochondrial ASncmtRNA knockdown reduce tumorigenic properties of malignant breast cancer cells.

During intercellular communication, cells release extracellular vesicles such as exosomes, which contain proteins, ncRNAs and mRNAs that can influence proliferation and/or trigger apoptosis in recipient cells, and have been proposed to play an essential role in promoting invasion of tumor cells and in the preparation of metastatic niches. Our group proposed the antisense non-coding mitochondrial RNA (ASncmtRNA) as a new target for cancer therapy. ASncmtRNA knockdown using an antisense oligonucleotide (ASO-1537S) causes massive death of tumor cells but not normal cells and strongly reduces metastasis in mice. In this work, we report that exosomes derived from ASO-1537S-treated MDA-MB-231 breast cancer cells (Exo-1537S) inhibits tumorigenesis of recipient cells, in contrast to exosomes derived from control-ASO-treated cells (Exo-C) which, in contrast, enhance these properties. Furthermore, an in vivo murine peritoneal carcinomatosis model showed that Exo-1537S injection reduced tumorigenicity compared to controls. Proteomic analysis revealed the presence of Lactadherin and VE-Cadherin in exosomes derived from untreated cells (Exo-WT) and Exo-C but not in Exo-1537S, and the latter displayed enrichment of proteasomal subunits. These results suggest a role for these proteins in modulation of tumorigenic properties of exosome-recipient cells. Our results shed light on the mechanisms through which ASncmtRNA knockdown affects the preparation of breast cancer metastatic niches in a peritoneal carcinomatosis model.

A filamentous bacteriophage targeted to carcinoembryonic antigen induces tumor regression in mouse models of colorectal cancer.

Colorectal cancer is a deadly disease, which is frequently diagnosed at advanced stages, where conventional treatments are no longer effective. Cancer immunotherapy has emerged as a new form to treat different malignancies by turning-on the immune system against tumors. However, tumors are able to evade antitumor immune responses by promoting an immunosuppressive microenvironment. Single-stranded DNA containing M13 bacteriophages are highly immunogenic and can be specifically targeted to the surface of tumor cells to trigger inflammation and infiltration of activated innate immune cells, overcoming tumor-associated immunosuppression and promoting antitumor immunity. Carcinoembryonic antigen (CEA) is highly expressed in colorectal cancers and has been shown to promote several malignant features of colorectal cancer cells. In this work, we targeted M13 bacteriophage to CEA, a tumor-associated antigen over-expressed in a high proportion of colorectal cancers but largely absent in normal cells. The CEA-targeted M13 bacteriophage was shown to specifically bind to purified CEA and CEA-expressing tumor cells in vitro. Both intratumoral and systemic administration of CEA-specific bacteriophages significantly reduced tumor growth of mouse models of colorectal cancer, as compared to PBS and control bacteriophage administration. CEA-specific bacteriophages promoted tumor infiltration of neutrophils and macrophages, as well as maturation dendritic cells in tumor-draining lymph nodes, suggesting that antitumor T-cell responses were elicited. Finally, we demonstrated that tumor protection provided by CEA-specific bacteriophage particles is mediated by CD8+ T cells, as depletion of circulating CD8+ T cells completely abrogated antitumor protection. In summary, we demonstrated that CEA-specific M13 bacteriophages represent a potential immunotherapy against colorectal cancer.

[The association of schizophrenia with chronic non transmissible diseases]. / Esquizofrenia y su asociación con enfermedades médicas crónicas.

The life expectancy of patients with schizophrenia (SCH) is 11 to 20 years less than the general population. There is an association between SCH and various diseases and chronic conditions, highlighting the cardio-metabolic diseases. This association has been attributed to the use of antipsychotics, however, evidence has also shown intrinsic susceptibility of schizophrenic patients the development of chronic conditions. This review aims to update knowledge about chronic conditions such as cardiometabolic risk and sleep, bone and kidney disorders related to SCH. These patients have a high prevalence of risk behaviors, including smoking and poor diet. They have a worse metabolic profile than the general population and a greater likelihood of developing metabolic syndrome, diabetes and cardiovascular disease. SCH has also been associated with other chronic diseases such as osteoporosis and chronic kidney disease. The high prevalence of these comorbidities in schizophrenic population is not explained solely by the antipsychotic treatment, therefore intrinsic mechanisms associated to SCH are postulated to be associated with these conditions. This new information requires a change in the multidisciplinary medical approach for the study and management of schizophrenic patients.

Treatment satisfaction with injectable disease-modifying therapies in patients with relapsing-remitting multiple sclerosis (the STICK study).

BACKGROUND: Treatment satisfaction in patients with relapsing-remitting multiple sclerosis (RRMS) may impact adherence and thus clinical outcomes. The objective of this study was to measure the satisfaction of patients with RRMS with injectable disease-modifying therapies (DMTs) and to evaluate the factors associated with treatment satisfaction. MATERIAL AND METHODS: In this observational retrospective study conducted in the neurology departments of 35 hospitals throughout Spain, demographic data, disease characteristics, and information on treatment with injectable DMTs were collected at a single scheduled visit. Treatment satisfaction was assessed using the Treatment Satisfaction Questionnaire for Medication (TSQM), version 1.4. Patients also answered complementary questions about the factors that might affect treatment satisfaction. The data collected were analyzed descriptively. A regression model was used to explore the factors associated with treatment satisfaction. RESULTS: The study included 445 patients (mean±SD age, 41±10.2 years; two-thirds women). The percentages treated with each DMT were Avonex 28.5%, Rebif 44 µg 24.5%, Copaxone 22.5%, Betaferon 13.0%, Rebif22 µg 8.3% and Extavia 3.1%. The mean±SD overall satisfaction according to the TSQM was 68.8±18.6 and the highest overall satisfaction was reported for Rebif 22 µg (72.4±20.3) and the lowest for Extavia (61.7±23.7). In the regression analysis, rehabilitation, interference with social life, pain on injection and number of MS treatments received were significantly associated with a decrease in overall TSMQ score. A small but significant negative correlation was found between EDSS scores and TSMQ scores (rho = -0.11, p = 0.02) and effectiveness (rho = -0.17, p<0.001). A perceived inconvenience of injections was reflected by the stated preference of 83% for once-daily oral treatment over other administration routes. CONCLUSIONS: Patients on stable injectable DMT therapy were reasonably satisfied with their treatment. Our results suggest that the main source of dissatisfaction with the current treatment is the inconvenience of the administration regimen.

Esquizofrenia y su asociación con enfermedades médicas crónicas / The association of schizophrenia with chronic non transmissible diseases

The life expectancy of patients with schizophrenia (SCH) is 11 to 20 years less than the general population. There is an association between SCH and various diseases and chronic conditions, highlighting the cardio-metabolic diseases. This association has been attributed to the use of antipsychotics, however, evidence has also shown intrinsic susceptibility of schizophrenic patients the development of chronic conditions. This review aims to update knowledge about chronic conditions such as cardiometabolic risk and sleep, bone and kidney disorders related to SCH. These patients have a high prevalence of risk behaviors, including smoking and poor diet. They have a worse metabolic profile than the general population and a greater likelihood of developing metabolic syndrome, diabetes and cardiovascular disease. SCH has also been associated with other chronic diseases such as osteoporosis and chronic kidney disease. The high prevalence of these comorbidities in schizophrenic population is not explained solely by the antipsychotic treatment, therefore intrinsic mechanisms associated to SCH are postulated to be associated with these conditions. This new information requires a change in the multidisciplinary medical approach for the study and management of schizophrenic patients.

El juicio de realidad y mundos posibles en personas con esquizofrenia / The judgment of reality and possible Worlds in persons with schizophrenia

Resumen El juicio de realidad conservado presupone el ejercicio de nuestra capacidad para procesar la realidad y adquirir conciencia de ella. Dicha conciencia se enmarca en la endoculturación que nos provee de marcos informativos compartidos que nos permiten la comprensión de quienes somos, de nuestra identidad y de los roles que abordamos en el medio psicosocial al que pertenecemos, es decir, lo que aceptamos como mundos posibles. En la esquizofrenia, el juicio de realidad es una interpretación de la realidad sesgada por el delirio. En psiquiatría se evalúa el juicio de realidad en el marco de la tarea de describir el propio proceso mórbido. En este proceso se develan diversos mecanismos de construcción de juicio con el que los pacientes interpretan sus vivencias (Figueroa, 2015). En el presente estudio intentaremos describir algunas evidencias del juicio de realidad alterado a través del empleo de modalizadores discursivos, que describiremos en el marco de la Lingüística Clínica Funcional. Nuestro objetivo general es describir el empleo de recursos comunicativos que marcan esta conducta psicopatológica. La hipótesis del estudio es que el juicio de realidad alterado puede pesquisarse a través del empleo de modalizadores verbales de certidumbre o posibilidad.

The judgment of conserved reality presupposes the exercise of our capacity to process reality and become aware of it. This awareness is framed in the endoculturation that provides us with shared information frames that allow us to understand who we are, our identity and the roles we address in the psychosocial environment to which we belong, that is, what we accept as possible worlds. In schizophrenia, the judgment of reality is an interpretation of reality biased by delirium. In psychiatry the judgment of reality is evaluated in the context of the task of describing the morbid process itself. In this process, different mechanisms of judgment building are revealed, with which patients interpret their experiences (Figueroa, 2015). In the present study we will try to describe some evidences of the judgment of altered reality through the use of discursive modalizers, which we will describe in the framework of Functional Clinical Linguistics. Our general objective is to describe the use of communicative resources that mark this psychopathological behavior. The hypothesis of the study is that the altered reality judgment can be investigated through the use of verbal modalizers of certainty or possibility.

Bile fistula after penetrating hepatic trauma withexpectant management in the “era” of endoscopictreatment: clinical report / Fístula biliar secundaria a trauma hepático penetrante con conducta expectante en la “era” del tratamiento endoscópico: reporte clínico

Objective: to report a clinical case of bile fistula after penetrating hepatic trauma given its low incidence, which was expectant managed by not having endoscopic retrograde cholangiopancreatography. Clinical case: we present a 28 years-old man, with biliary fistula resulting after a penetrating hepatic trauma. Discussion: bile leakage is a major complication after liver surgery and a rare one in complication of major hepatic trauma. Conventional treatment has consisted of surgical intervention with hepatic debridement, ductal repair, controlled drainage and ERCP when available. Conclusion: biliary fistula was treated successfully with conservative management, the duration of time between hepatic trauma and closure of the fistula was 35 days.

Objetivo: reportar un caso clínico de fístula biliar secundaria a trauma hepático penetrante dada su baja incidencia, que fue tratado de manera convencional al no contar con colangiopancreatografía retrógrada endoscópica. Caso clínico: se presenta un hombre de 28 años de edad, con fístula biliar resultante de trauma hepático penetrante. Discusión: la fuga biliar es una complicación mayor después de cirugía hepática y una complicación poco frecuente después de un trauma hepático mayor. El tratamiento convencional ha consistido en intervención quirúrgica con debridación hepática, reparación ductal, una fistula controlada y ERCP cuando está disponible. Conclusión: la fístula biliar fue tratada exitosamente con manejo conservador, el tiempo entre el trauma hepático y el cierre de la fístula fue de 35 días.

Diseño y evaluación de proceso de una intervención comunitaria para la detección precoz del primer episodio de psicosis en Chile / Design and evaluation of a community intervention for early detection of the first episode of schizophrenia

Introducción: La esquizofrenia es una enfermedad mental que genera discapacidad, afectando la calidad de vida de la persona y de sus cuidadores. Las investigaciones demuestran que un menor tiempo de psicosis no tratada durante el primer episodio se asocia con un mejor pronóstico. Objetivo: En este trabajo se describe el diseño y evaluación de proceso de una intervención comunitaria para la detección precoz del primer episodio de psicosis, que fue aplicada en tres sectores del país (comunas de Iquique, La Granja y El Bosque) ligados a un servicio de salud mental. Material y método: Para la evaluación se utilizó una metodología cualitativa de tipo etnográfica, basada en entrevistas semi-estructuradas y entrevistas grupales con los diferentes tipos de participantes (profesores, coordinadores, profesionales médicos y no médicos). Resultados: La evaluación de proceso de esta intervención permitió concluir que contribuyó al cumplimiento de los objetivos de la intervención de manera heterogénea; se obtuvo una buena participación de médicos y profesores; la capacitación fue bien evaluada. Conclusiones: Las recomendaciones principales fueron: 1) obtener respaldo político (autoridades sanitarias locales), 2) crear y mantener vínculos cercanos con el equipo investigador, y 3) adecuar la intervención a los valores y/o necesidades de la comunidad.

Introduction: Schizophrenia is a disabling mental illness that affects the quality of life of both the sufferer and their caretakers. Research has shown that quick diagnosis and treatment of the first episode is associated with better prognosis. Objective: In this paper, the design and evaluation of a community intervention for early detection of the first episode of psychosis in three sectors of the country (municipalities of Iquique, La Granja and El Bosque) is described. Materials and Methods: For the evaluation, a qualitative, ethnographic methodology was used, based in semi-structured and group interviews with different categories of participants (teachers, coordinators, medical professionals and non-medical professionals). Results: Evaluation of this intervention shows that the objectives were fulfilled unequally. A high level of participation was obtained from doctors and teachers, and the training was positively evaluated. Conclusions: The main recommendations were, 1) obtain political support (local health authorities), 2) create and manage close relationships within the research team, and 3) modify the intervention to serve the needs and values of each community.

Oxigenoterapia hiperbárica en el tratamiento de la Cistitis hemorrágica posradioterapia: experiencia en el Hospital Militar Central / Hyperbaric oxigen therapy in treatmen post-radiotherapy hemorrhagic cystitis. Experience of Hospital Militar Central in Bogotá

El objetivo del trabajo fue describir el curso de la cistitis hemorrágica posradioterapia pélvica con la terapia de oxígeno hiperbárico (OTHB). Se hizo un estudio descriptivo retrospectivo, en el que se revisaron las historias de diez pacientes atendidos en el Servicio de Medicina Hiperbárica del Hospital Militar Central de Bogotá, remitidos del Servicio de Urología de la misma institución con el diagnóstico de cistitis hemorrágica postradioterapia, en un período comprendido entre enero de 2001 a febrero de 2007. Los resultados se tabularon con las variables preestablecidas y se procesaron en Excel. El 70 por ciento de los pacientes fueron hombres, la edad promedio fue 74,3 años (63-88), el 70 por ciento tuvo cistitis y proctitis posradioterapia y el restante sólo cistitis. Todos los hombres fueron irradiados por cáncer de próstata y las mujeres por cáncer de cérvix. El 40 por ciento recibió braquiterapia y el promedio de sesiones de OTHB fue de doce, en un rango entre siete y quince. El tiempo promedio de inicio de los síntomas fue de 16,4 meses y el de seguimiento después de iniciada la OTHB fue de 1,6 años. Al final del seguimiento todos los pacientes estuvieron asintomáticos, lo que permite concluir que la del OTHB es una alternativa útil y segura en el tratamiento de los pacientes con cistitis hemorrágica posradioterapia.

Luxofractura cervical completa C5-C6 con paciente neurológicamente indemne. Reporte de un caso

Reportamos y discutimos un caso de luxofractura cervical completa C5-C6, en un paciente neurológicamente indemne al seguimiento, quien fue tratado mediante reducción cerrada seguida inmediatamente de fusión, artrodesis y fijación interna con placas, vía posterior. Luxaciones y luxofracturas a nivel de la columna cervical baja(C3-C7) implican por definición inestabilidad mecánica, además pueden asociarse con algún tipo de déficit neurológico parcial o completo. Para un manejo adecuado de este tipo de lesiones se debe analizar en forma independiente el aspecto mecánico y el aspecto neurológico. La inestabilidad mecánica se controla estabilizando la columna, lo cual usualmente comprende reducción, fusión, artrodesis y fijación interna con osteosíntesis; tradicionalmente la reducción se ha efectuado en forma cerrada, utilizando tracción esquelética craneana progresiva, bajo el control clínico del estado neurológico del paciente. Desde el punto de vista neurológico, especialmente en aquellos casos con déficit parcial estable o progresivo, se justifica la restitución inmediata de la anatomía vertebral a la normalidad. Esta restitución puede diferirse en presencia de pacientes con déficit neurológico completo o en ausencia del mismo, es decir pacientes sin ningún déficit; sin embargo, es innegable que la estabilización precoz de la columna en la medida que facilita enormemente los cuidados de enfermería y la rehabilitación, disminuye los riesgos de deterioro neurológico con la movilización del paciente. A pesar de las consideraciones anteriores, se debe tener mucha cautela antes de proceder a la reducción de una luxación o luxofractura; existen reportes en la literatura de lesiones neurológicas atribuidas a herniación del disco intervertebral durante el trauma o durante la maniobra de reducción, con prevalencias que van del 0 al 50 por ciento. Debemos por lo tanto efectuar un diagnóstico exacto del estado anatómico del disco, empleando la resonancia magnética como paso previo a cualquier procedimiento terapéutico, en su defecto otras alternativas diagnósticas serían la mielografía y/o tomografía axial computarizada