100 results on '"Iván, Roa"'
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2. Caracterización de la participación política de jóvenes. Ruta metodológica transmedia
- Author
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Carmen Burgos Videla, Jairo Antonio Pérez, Elías Manaced Rey Vásquez, and Iván Roa Ovalle
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Visual Arts and Performing Arts - Abstract
Polifonías como proyecto da cuenta del Pensamiento político de los jóvenes a través de las narrativas transmedia, emerge del problema sobre participación política y ciudadana de los jóvenes. El aparato metodológico usado fue la propuesta etnografía transmedia. En la primera etapa del estudio se da cuenta de diversas formas de participación de jóvenes y concepciones sobre lo político y lo democrático. Se desarrolla una herramienta de diagnóstico gamificada que entrega como resultado datos sobre la descripción de la muestra en cuanto a posturas diversas de los jóvenes frente al ejercicio de la política y la toma de decisiones.
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- 2023
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3. Técnicas de la Inmunoperoxidasa y su aplicación en anatomía patológica
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Iván Roa E., Sergio González B., and Mireya Delgado A.
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tã©cnicas para inmunoenzimas ,anatomãa patolã³gica ,Medicine - Abstract
Sin resumen
- Published
- 2017
4. HOW TO TRANSFORM THREE ON-SITE UNIVERSITIES INTO A DISTANCE LEARNING UNIVERSITY? THE EXPERIENCE OF CEU UNIVERSITIES
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Angela Magnet, Laura Amado, Gerardo Manuel Antón, Alberto Arnau, Riánsares Arriazu, Carlos Ignacio Baeza, Sara Barquero, María José Baselga, Vanesa Berlanga, Emiliano Blasco, Fernando Bonete, Ángel Javier Castaños, María Isabel Castilla, Juan Manuel Corpa, Irene Correas, Guillermo de la Calle, Alfonso Diaz, Patricia Elhazaz, Ana María Enrique, Lucana Estevez, Juan Carlos Frias, Pablo Gallego, Rodrigo García Carmona, Empar García Roselló, Rosa García Vilardell, Lucia Hilario, Cristina Isabel Dopacio, Juan Francisco Jiménez Jacinto, Begoña Jiménez Reguera, Jaume Vicent Jordá, Antonio López Álvarez, Ana Isabel Mateos, José Luis Mateu, Jose María Mira de Orduña, Santiago Molina, Edgar Mozas, Ricardo Palomo, Francisco Pardo, María Fernanda Rey-Stolle, Iván Roa, José Antonio Robles, Francisco Javier Ruperez, Idoia Ana Salazar, María Sánchez Martínez, Juan Ignacio Sanz, Sergio Saugar, Bartolomé Serra, Fernando Serrano, José Miguel Soria, Francisco Suay, Manuel Tirado, José Torregosa, and Noemí Valtueña
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- 2023
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5. Expression of teneurins is associated with tumor differentiation and patient survival in ovarian cancer.
- Author
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Rebecca Graumann, Gabriella A Di Capua, Juan E Oyarzún, Marcos A Vásquez, Christine Liao, Jorge A Brañes, Iván Roa, Paola Casanello, Alejandro H Corvalán, Gareth I Owen, Iris Delgado, Uwe Zangemeister-Wittke, and Annemarie Ziegler
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Medicine ,Science - Abstract
Teneurins are a family of highly conserved pair-rule proteins involved in morphogenesis and development of the central nervous system. Their function in adult tissues and in disease is largely unknown. Recent evidence suggests a role for dysregulated expression of Teneurins in human tumors, but systematic investigations are missing. Here, we investigated Teneurin-2 and Teneurin-4 expression in various cancer cell lines and in ovarian tumor tissues. Teneurin-2 and Teneurin-4 were expressed in most of the breast cancer cell lines tested. Teneurin-4 was also detected in ovarian cancer cell lines, and throughout ovarian tumors and normal ovary tissue. Ovarian tumors with low Teneurin-4 expression showed less differentiated phenotypes and these patients had shorter mean overall survival. Similarly, Teneurin-2 expression correlated with overall survival as well, especially in patients with serous tumors. In the various cell lines, 5-Aza-cytidine-induced changes in DNA methylation did not alter expression of Teneurin-2 and Teneurin-4, despite the existence of predicted CpG islands in both genes. Interestingly, however, we found evidence for the control of Teneurin-2 expression by the oncogenic growth factor FGF8. Furthermore, we identified multiple transcript splicing variants for Teneurin-2 and Teneurin-4, indicating complex gene expression patterns in malignant cells. Finally, downregulation of Teneurin-4 expression using siRNA caused a cell-type dependent increase in proliferation and resistance to cisplatin. Altogether, our data suggest that low Teneurin-4 expression provides a growth advantage to cancer cells and marks an undifferentiated state characterized by increased drug resistance and clinical aggressiveness. We conclude that Teneurin-2 and Teneurin-4 expression levels could be of prognostic value in ovarian cancer.
- Published
- 2017
- Full Text
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6. CARACTERIZACIÓN DE LA PARTICIPACIÓN POLITICA DE JÓVENES. RUTA METODOLÓGICA TRANSMEDIA.
- Author
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BURGOS VIDELA, CARMEN, ANTONIO PÉREZ, JAIRO, REY VÁSQUEZ, ELÍAS MANACED, and OVALLE, IVÁN ROA
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YOUNG adults ,TRANSMEDIA storytelling ,POLITICAL participation ,POLITICAL philosophy ,COMMUNICATION methodology ,ETHNOLOGY ,PRACTICAL politics - Abstract
Copyright of Visual Review is the property of Eagora Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
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7. Costos del estatus epiléptico en adultos mayores: estudio basado en población cautiva en Argentina
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Víctor Diaz, Joaquín Machado, Alejandro Fernández, Victoria Carabajal, Pablo Ioli, Luciana Carobolante, Lucas Martín Romano, Luciana Rodríguez Rolfi, Iván Roa, and Sergio Eduardo Gonorazky
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03 medical and health sciences ,0302 clinical medicine ,Neurology ,030212 general & internal medicine ,Neurology (clinical) ,030217 neurology & neurosurgery - Abstract
Resumen Introduccion El estatus epileptico (SE, por sus siglas en ingles) es una urgencia medica y neurologica que se asocia con una elevada tasa de morbimortalidad, siendo uno de los mayores problemas en la salud publica de todo el mundo. Existe evidencia emergente que el SE provoca cuidados intensivos prolongados, tratamiento prolongado o de amplia variedad y altos costos indirectos. Objetivo Proporcionar datos sobre los costos de hospitalizacion en pacientes con SE. Materiales y metodos Se obtuvieron los datos prospectivamente de todos los casos de SE consecutivos entre el 1 de abril del 2007 y el 31 de mayo del 2013 inclusive, en pacientes ≥ 20 anos. Resultados Se registraron 359 ingresos hospitalarios en una cohorte de 325 pacientes. El 63% de las admisiones tuvieron un SE no refractario (SENR, por sus siglas en ingles), el 32% SE refractario (SER, por sus siglas en ingles) y el 5% SE superrefractario (SESR, por sus siglas en ingles). La mediana de costos totales fue de 2.185,04 USD$ por SE; con un incremento estadisticamente significativo (p Conclusion Los datos expuestos, a nuestro saber, constituyen el primer estudio de costos en el SE realizado en Argentina y America Latina, con elevados costos directos de atencion medica, sin embargo, los mismos fueron menores a los observados en trabajos previos de paises desarrollados.
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- 2019
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8. Innovation in the teaching-learning process: the case of Kahoot!
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Juan José Guardia, José Luis Del Olmo, Iván Roa, and Vanesa Berlanga
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Higher education ,Computer science ,business.industry ,Process (engineering) ,010401 analytical chemistry ,05 social sciences ,Learning assessment ,050301 education ,01 natural sciences ,0104 chemical sciences ,Education ,Training skills ,Participatory evaluation ,Action (philosophy) ,Mathematics education ,Student learning ,business ,Teaching learning ,0503 education - Abstract
Purpose In recent years, a process of reform and innovation in higher education has been witnessed. A change in the evaluation of student learning in universities is necessary for new teaching-learning proposals to be developed. The authors propose implementing a learning assessment process based on the idea of participatory evaluation, verifying the benefits of this method in the acquisition of cross-disciplinary skills. Design/methodology/approach The method implemented follows the principles of action research. Findings The Kahoot! app has an effect on the teaching-learning process and on the training skills and academic performance measured through the student’s grades. Originality/value This paper presents an innovation proposal that aims to observe how students acquire more competences.
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- 2019
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9. Infarto agudo al miocardio secundario a disección coronaria espontánea biarterial: Reporte de un caso y revisión de literatura
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Iván Roa, Mathias Schwarze, Rodrigo Contreras, Hermann Schwarze, Bastián Abarca, and Pablo Rodríguez
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intervención coronaria percutánea ,disección coronaria espontánea ,infarto miocárdico - Abstract
Resumen: La disección coronaria espontánea ha surgido como una causa interesante y poco reconocida de síndrome coronario agudo no aterosclerótico. Ocurre más frecuentemente en mujeres jóvenes, donde de forma importante puede asociarse a anomalías arteriales no coronarias. La clave para un tratamiento oportuno es el diagnóstico precoz que impida su evolución a cuadros más severos. Se presenta el caso de una mujer de 36 años con un síndrome coronario agudo secundario a una disección coronaria espontánea bi-arterial que evolucionó de forma grave a una insuficiencia cardíaca aguda. El objetivo es informar un cuadro poco usual y proporcionar evidencia que respalde el cómo debe enfrentarse.
- Published
- 2021
10. Cáncer de vesícula biliar, ¿La Contaminación por bilis afecta el pronóstico?
- Author
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Nicolas Solano, Xabier de Aretxabala, M. Vivanco, J. Hepp, G. Rencoret, Iván Roa, Oriana Valenzuela, and David Daroch
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General Engineering - Abstract
Introducción: En algunas áreas el cáncer de la vesícula biliar se detecta en hasta el 3,5% de los pacientes intervenidos por colelitiasis. Con el objetivo de evaluar el rol de la ruptura de la vesícula y la consiguiente contaminación por bilis, se evaluó una serie de pacientes portadores de cáncer de vesícula diagnosticado posterior a la colecistectomía. Material y Método: El estudio se efectuó en 109 pacientes en quienes se diagnosticó un cáncer de vesícula posterior a la colecistectomía. El grupo a estudiar se dividió de acuerdo a la ocurrencia o no de contaminación por bilis al momento de la colecistectomía, como también de acuerdo a la magnitud de esta. Resultados: De los pacientes estudiados, en 32 se documentó la ocurrencia de contaminación por bilis al momento de la colecistectomía. De estos, en 13 la contaminación fue considerada mayor. El tiempo promedio de seguimiento fue de 33 meses, 35 pacientes (32,1%) fallecieron durante el seguimiento. La sobrevida media de la totalidad de la serie que tuvo contaminación por bilis no se diferenció de los pacientes sin contaminación. Sin embargo el grupo que tuvo una contaminación catalogada como mayor, presentó una sobrevida estadísticamente inferior al resto de los pacientes. Finalmente se realizó un análisis mediante el modelo de regresión de COX que incluyo edad, genero, nivel de invasión y tipo de contaminación, resultando la existencia de contaminación mayor por bilis un factor independientemente asociado al pronóstico.Conclusión: La presencia de ruptura vesicular y contaminación mayor por bilis debiera considerarse un factor pronóstico.
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- 2020
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11. INNOVACIÓN DOCENTE EN EL PROCESO DE ENSEÑANZA-APRENDIZAJE: EL CASO KAHOOT!
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Jessica Paris, Vanessa Berlanga, Juan José Guardia, José Luis Del Olmo Arriaga, and Iván Roa
- Abstract
n los últimos años somos testigos de un proceso de reforma en la Educación Superior. Un cambio en la evaluación de los aprendizajes del alumnado se hace necesario para que puedan surgir nuevas propuestas de enseñanza-aprendizaje y, para que los roles preestablecidos históricamente puedan evolucionar. La investigación-acción cooperativa constituye una vía para optimizar estos procesos de enseñanza-aprendizaje. La línea de investigación que se presenta propone una alternativa a la evaluación tradicional universitaria. Para ello, se propone implementar un proceso de evaluación de aprendizaje basado en la noción de evaluación participativa, verificando los beneficios de esta metodología en la adquisición de competencias transversales y en la consiguiente mejora del aprendizaje del alumnado. Se plantea una propuesta de innovación que pretende observar cómo los alumnos dejan de percibir la evaluación como un hecho traumático y pasa a ser entendida como una vía de aprendizaje. La metodología implementada sigue los preceptos de la investigación-acción. Las expectativas de la aplicación de la evaluación participativa en el aula radican en que el alumnado mejore competencias transversales como el trabajo en equipo, la interdependencia, la autonomía, la expresión oral, la gestión del tiempo y la competencia crítica, además de las competencias específicas de cada materia implicada en el proyecto. Palabras clave: Educación superior, Gamificación, Habilidades, Proceso de aprendizaje, Proceso de innovación docente
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- 2018
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12. Gallbladder cancer in Chile
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Iván Roa and Xabier de Aretxabala
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Oncology ,medicine.medical_specialty ,Cost-Benefit Analysis ,medicine.medical_treatment ,Antineoplastic Agents ,Disease ,Internal medicine ,medicine ,Humans ,Cholecystectomy ,Genetic Predisposition to Disease ,Molecular Targeted Therapy ,Chile ,Gallbladder cancer ,Molecular pathology ,business.industry ,Incidence ,General surgery ,Incidence (epidemiology) ,Gastroenterology ,Cancer ,medicine.disease ,Early Diagnosis ,Gallbladder Neoplasms ,Gallbladder Neoplasm ,business - Abstract
Gallbladder cancer (GBC) should be considered an orphan disease in oncology and represent a unique carcinogenetic model. This review will analyse some of the current aspects of GBC.Chile has the highest incidence and mortality of GBC in the world. Most patients are diagnosed in advanced stages with few treatment options. During the last two decades, little progress has been made in early diagnosis and treatment. At the molecular level, recent access to next-generation sequencing and other techniques for detecting the mutations of multiple genes have made advances in this area.The use of therapies targeted according to the detection of specific molecular alterations is in the early stages of evaluation and could represent a significant advance in the treatment of a large number of patients from developing countries.
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- 2015
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13. Gallbladder cancer: role of laparoscopy in the management of potentially resectable tumors
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Iván Roa, Jorge Leon, Xabier de Aretxabala, J. Hepp, and Fernando Maluenda
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Adult ,Male ,Reoperation ,medicine.medical_specialty ,medicine.medical_treatment ,Bile duct cancer ,Internal medicine ,Humans ,Medicine ,Neoplasm Invasiveness ,Gallbladder cancer ,Laparoscopy ,Aged ,medicine.diagnostic_test ,business.industry ,General surgery ,Cancer ,Middle Aged ,Hepatology ,medicine.disease ,Endoscopy ,Treatment Outcome ,Cholecystectomy, Laparoscopic ,Lymph Node Excision ,Female ,Gallbladder Neoplasms ,Surgery ,Cholecystectomy ,Lymphadenectomy ,Tomography, X-Ray Computed ,business - Abstract
The aim of this study was to evaluate the role that laparoscopy plays in the management of gallbladder cancer.From August 2005 to March 2009, 23 patients affected by gallbladder cancer detected after the study of a cholecystectomy specimen underwent laparoscopy as part of their management.Among the patients, 5 underwent only an exploratory laparoscopy, while 11 were converted due to the existence of dense adhesions that precluded a complete exploration. Of the patients with adhesions who underwent conversion, three were unresectable. The remainder underwent a lymphadenectomy and liver resection after conversion. Of the seven who underwent a complete laparoscopic exploration, five had a lymphadenectomy and liver resection done completely by laparoscopy while conversion was needed for two. Conversion was required due to lymphatic metastasis at the hepatic pedicle and the presence of a bile leak. Postoperative time was uneventful, with patients discharged within 3 days of the operation.Laparoscopy may be employed in the management of patients with early forms of gallbladder cancer undergoing reoperation. Although the presence of adhesions may result in inadequate exploration, there is a subset of patients for whom it is possible to perform a complete exam. Furthermore, laparoscopic lymphadenectomy and gallbladder bed resection is a promising technique in well-selected patients.
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- 2010
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14. Early gallbladder cancer: Is further treatment necessary?
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Iván Roa, Juan Carlos Roa, Gerardo Mordojovich, Fernando Maluenda, J. Hepp, Jorge Leon, and Xabier de Aretxabala
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medicine.medical_specialty ,business.industry ,Standard treatment ,medicine.medical_treatment ,Retrospective cohort study ,General Medicine ,Favorable prognosis ,medicine.disease ,Rokitansky–Aschoff sinuses ,Surgery ,Oncology ,medicine ,Cholecystectomy ,Gallbladder cancer ,business ,Survival rate ,Infiltration (medical) - Abstract
Background and Objectives: The goal of this study was to evaluate a series of patients with early gallbladder cancer, focusing on the selection of treatment and the role of Rokitansky Aschoff sinus infiltration. Methods: We performed a retrospective analysis of a prospective series of 371 patients with gallbladder cancer. Specimens were reviewed by an independent pathologist to confirm the diagnosis and depth of infiltration and to evaluate the presence of Rokitansky Aschoff sinus involvement. Results: Forty-nine and 45 patients with muscular (pT1b) and mucosal (pT1a) infiltration gallbladder cancer tumors were studied respectively. Simple cholecystectomy was the treatment in all patients, with the exception of 11 patients who underwent further surgery. Rokitansky Aschoff sinus invasion was seen in seven patients with mucosa (pT1a) and three with muscular (pT1b) compromise. The 5-year survival rates of patients with muscular (pT1b) and mucosal (pT1a) infiltration were 87.6% and 86.4%, respectively. Patients with Rokitansky Aschoff involvement had a lower survival rate than those with no involvement in both categories. Conclusions: Early gallbladder cancer is associated with a favorable prognosis and cholecystectomy should be the standard treatment. Despite some patients having a worse prognosis, there are no data to support more aggressive treatment. J. Surg. Oncol. 2009 Wiley-Liss, Inc.
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- 2009
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15. Efecto de la fijación en la calidad del ADN: estudio controlado con cinco fijadores
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E. Iván Roa, M. Felipe Benavente, Angélica Melo, S. Juan Carlos Roa, and M. Patricia García
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Pathology and Forensic Medicine - Abstract
Resumen Antecedentes Los tejidos fijados y embebidos en parafina son una fuente importante de material para diagnostico e investigacion. La amplificacion de ADN desde este tipo de tejidos, mediante reaccion en cadena de la polimerasa (PCR), es afectada por el tipo de fijador y los tiempos de fijacion empleados. Para determinar el parametro que mejor se adecue a las condiciones de trabajo de nuestro laboratorio de Patologia Molecular, evaluamos el efecto de cinco fijadores sobre la calidad del ADN bajo condiciones controladas. Material y Metodo Muestras de mucosa gastrica fueron fijadas, embebidas en parafina y luego procesadas para extraccion de ADN empleando un protocolo basado en digestion con proteinasa K. La calidad del ADN se evaluo mediante amplificacion de tres fragmentos del gen β-globina (268, 536 y 989 pb). Resultados No observamos mayores diferencias entre fijadores ni tiempos de fijacion en la amplificacion de ADN de 268 y 536 pb. No obstante, la amplificacion del fragmento mayor (981 pb) se vio alterada al aumentar el tiempo de fijacion, a excepcion de aquellas muestras fijadas en etanol 70% que presentaron una banda de similar intensidad a la obtenida para muestras control (tejido fresco congelado). Conclusiones Estos resultados nos proporcionan una pauta para el diseno de experimentos de acuerdo a la calidad del material archivado, optimizando recursos humanos e insumos.
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- 2006
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16. Técnicas de la Inmunoperoxidasa y su aplicación en anatomía patológica
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B Sergio González, E Iván Roa, and A Mireya Delgado
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Técnicas para inmunoenzimas ,lcsh:R5-920 ,lcsh:R ,lcsh:Medicine ,General Medicine ,Anatomía patológica ,lcsh:Medicine (General) - Abstract
Sin resumen
- Published
- 2017
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17. Expression of teneurins is associated with tumor differentiation and patient survival in ovarian cancer
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Gareth I. Owen, Gabriella A. Di Capua, Rebecca Graumann, Paola Casanello, Jorge Brañes, Marcos Vasquez, Alejandro H. Corvalan, Juan E. Oyarzún, Uwe Zangemeister-Wittke, Annemarie Ziegler, Christine Liao, Iris Delgado, and Iván Roa
- Subjects
0301 basic medicine ,Pathology ,lcsh:Medicine ,Gene Expression ,Artificial Gene Amplification and Extension ,Polymerase Chain Reaction ,Biochemistry ,Ovarian tumor ,Gene expression ,Medicine and Health Sciences ,Small interfering RNAs ,RNA, Small Interfering ,lcsh:Science ,610 Medicine & health ,Ovarian Neoplasms ,Regulation of gene expression ,DNA methylation ,Multidisciplinary ,Cell Differentiation ,Phenotype ,Chromatin ,Ovarian Cancer ,Gene Expression Regulation, Neoplastic ,Survival Rate ,Nucleic acids ,Oncology ,Female ,Epigenetics ,DNA modification ,Chromatin modification ,Research Article ,Chromosome biology ,Cell biology ,medicine.medical_specialty ,Down-Regulation ,Nerve Tissue Proteins ,Biology ,Real-Time Polymerase Chain Reaction ,Research and Analysis Methods ,03 medical and health sciences ,Malignant Tumors ,Cell Line, Tumor ,Genetics ,medicine ,Humans ,Gene silencing ,Gene Silencing ,Molecular Biology Techniques ,Non-coding RNA ,Molecular Biology ,Differentiated Tumors ,lcsh:R ,Biology and Life Sciences ,Cancers and Neoplasms ,DNA ,Reverse Transcriptase-Polymerase Chain Reaction ,medicine.disease ,Gene regulation ,030104 developmental biology ,Cancer cell ,Cancer research ,RNA ,lcsh:Q ,CpG Islands ,Ovarian cancer ,Gynecological Tumors - Abstract
Teneurins are a family of highly conserved pair-rule proteins involved in morphogenesis and development of the central nervous system. Their function in adult tissues and in disease is largely unknown. Recent evidence suggests a role for dysregulated expression of Teneurins in human tumors, but systematic investigations are missing. Here, we investigated Teneurin-2 and Teneurin-4 expression in various cancer cell lines and in ovarian tumor tissues. Teneurin-2 and Teneurin-4 were expressed in most of the breast cancer cell lines tested. Teneurin-4 was also detected in ovarian cancer cell lines, and throughout ovarian tumors and normal ovary tissue. Ovarian tumors with low Teneurin-4 expression showed less differentiated phenotypes and these patients had shorter mean overall survival. Similarly, Teneurin-2 expression correlated with overall survival as well, especially in patients with serous tumors. In the various cell lines, 5-Aza-cytidine-induced changes in DNA methylation did not alter expression of Teneurin-2 and Teneurin-4, despite the existence of predicted CpG islands in both genes. Interestingly, however, we found evidence for the control of Teneurin-2 expression by the oncogenic growth factor FGF8. Furthermore, we identified multiple transcript splicing variants for Teneurin-2 and Teneurin-4, indicating complex gene expression patterns in malignant cells. Finally, downregulation of Teneurin-4 expression using siRNA caused a cell-type dependent increase in proliferation and resistance to cisplatin. Altogether, our data suggest that low Teneurin-4 expression provides a growth advantage to cancer cells and marks an undifferentiated state characterized by increased drug resistance and clinical aggressiveness. We conclude that Teneurin-2 and Teneurin-4 expression levels could be of prognostic value in ovarian cancer.
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- 2017
- Full Text
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18. Gallbladder cancer in Chile: Pathologic characteristics of survival and prognostic factors: analysis of 1,366 cases
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Iván, Roa, Gilda, Ibacache, Sergio, Muñoz, and Xabier, de Aretxabala
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Adult ,Male ,Sex Factors ,Gallbladder ,Humans ,Cholecystectomy ,Female ,Gallbladder Neoplasms ,Chile ,Middle Aged ,Prognosis ,Aged - Abstract
To explore gallbladder cancer (GBC), the second leading cause of cancer-related death in women in Chile.Analysis of macroscopic and microscopic variables, morphometry, and survival in 1,366 patients with GBC.Patients comprised 1,138 women and 228 men; diagnoses included 213 (15.6%) cases of mucosal carcinoma, 132 (9.7%) cases of muscular carcinoma, 316 (23.1%) cases of subserosal carcinoma, 382 (28.0%) cases of serosal carcinoma, and 323 (23.6%) cases beyond the serosa. Women older than 55 years with a gallbladder length greater than 9.5 cm had a five-times-greater relative risk of cancer. Those with a gallbladder wall thickness less than 7 mm had a better 5-year survival rate than those with a gallbladder wall thickness greater than 10 mm (P = .0001). Patients who had cholesterolosis of the gallbladder had 9.2 times less probability of having cancer. The infiltration level of the gallbladder wall was the most important independent prognostic factor (P.001), followed by differentiation and lymphatic involvement (P.001 and P = .05, respectively). Vascular infiltration had a mortality rate of 100%.Morphologic features are strongly associated with the prognosis of GBC and must be taken into consideration when supplementary treatment is recommended.
- Published
- 2014
19. Overexpression of the HER2/neu Gene: A New Therapeutic Possibility for Patients With Advanced Gallbladder Cancer
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Iván, Roa, Gonzalo, de Toro, Kurt, Schalper, Xabier, de Aretxabala, Chaitanya, Churi, and Milind, Javle
- Subjects
Original Research - Abstract
The HER2/neu gene is a proto-oncogene that can predict the response to treatment with trastuzumab, pertuzumab, and lapatinib. This study was conducted to determine the frequency of HER2/neu overexpression and to identify a subgroup of patients with gallbladder cancer who would benefit from targeted therapy.Patients with gallbladder cancer (n = 187; 165 women and 22 men) with a recorded follow-up of at least 5 years were included, along with control subjects (n = 75). An automated immunohistochemical technique was used with an anti-ErbB2 antibody. Scoring was conducted according to the CAP/ASCO (College of American Pathologists/American Society of Clinical Oncology) criteria for breast cancer.Overexpression of HER2/neu was observed in 12.8% of the cases. Of those, 0% were mucosal, 14.3% muscular, 12.8% subserosal, and 10.6% serosal. In 20% of the cases, equivocal staining was observed. Overexpression was more frequent in the advanced cancers and in the better differentiated tumors (13.8% and 17.4%, respectively), but the difference was nonsignificant. The patients with overexpression of HER2/neu had a worse overall survival, when compared with those who had no expression at 5 years (34% vs. 41%).This is the single largest study of HER2/neu expression in gallbladder cancer to use commonly accepted scoring criteria. The results indicate that HER2/neu overexpression occurred in 14% of the advanced gallbladder cancer cases. This subgroup may benefit from inhibitors of the HER2/neu pathway.
- Published
- 2013
20. [HER2 gene amplification and overexpression in advanced gastric cancer]
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Iván, Roa, Jeannie, Slater, Daniel, Carvajal, Kurt, Schalper, Gonzalo, de Toro, Raúl, Ares, Anakaren, Game, Jorge, León, and Xabier, de Aretxabala
- Subjects
Male ,Stomach Neoplasms ,Tissue Array Analysis ,Gene Amplification ,Gene Expression ,Humans ,Female ,Adenocarcinoma ,Genes, erbB-2 ,Middle Aged ,In Situ Hybridization, Fluorescence ,Aged - Abstract
Overexpression/amplification of the HER2 gene in advanced gastric cancer is a predictor of response to adjuvant therapy with monoclonal antibodies.To determine the frequency of HER2 gene overexpression and amplification in advanced gastric cancer.One hundred nine advanced gastric cancer biopsy specimens, from 76 men and 33 women aged 67 ± 14 and 62 ± 12 years respectively, were selected. Three histological patterns (diffuse, intestinal and mixed) were recognized. Automated immunohistochemistry was performed with monoclonal c-erbB-2 (NCL-356) Novocastra. Fluorescent in situ hybridization (FISH) for HER2 was performed in positive cases.In 39% of cases, immunohistochemical staining was negative. It was 1+, 2+ and 3+ positive in 15, 36 and 11% of cases, respectively. It was positive in 16% and 3% of intestinal type and mixed carcinomas, respectively. It was negative in all diffuse carcinomas. FISH was performed in 39 (2 +) cases and in 11 (3 +) cases. The gene amplification was positive in two (2 +) and 11 (3 +) cases (11.9%). The overall concordance between immunohistochemical staining and in situ hybridization was 85%.In advanced gastric cancer, HER2 gene overexpression or amplification was observed in 11% and 12% of cases, respectively.
- Published
- 2013
21. [BRAF gene mutation in wild-type KRAS patients with colorectal cancers]
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Iván, Roa, Anakaren, Game, Carolina, Bizama, and Kurt, Schalper
- Subjects
Male ,Proto-Oncogene Proteins B-raf ,Genotype ,Adenocarcinoma ,Middle Aged ,Proto-Oncogene Proteins p21(ras) ,Proto-Oncogene Proteins ,Mutation ,ras Proteins ,Humans ,Female ,Colorectal Neoplasms ,Polymorphism, Restriction Fragment Length ,Neoplasm Staging - Abstract
In colorectal cancer, BRAF and KRAS mutation are mutually exclusive, but both are independent prognostic factors for the disease.To determine the frequency of BRAF V600E mutation in colorectal cancer.A KRAS mutation study was carried out in 100 tissue samples of primary and metastatic adenocarcinomas of colon and rectum from patients aged 61.1 ± 62 years (56 women). Negative KRAS mutation cases underwent study of BRAF V600E mutation by restriction fragment length polymorphism (RFLP) and direct sequencing.Primary tumors were located in the colon and rectum in 88 and six cases respectively. Five were liver metastases and in one case, the sample location was undetermined. Forty two samples were KRAS positive (mutated). In 12 of the 58 KRAS negative (wild type) samples, the V600E mutation in codon 15 of the BRAF gene was demonstrated. No differences in the frequency and distribution of mutations, stratified by gender, age, primary tumor versus metastasis, or tumor location were observed.Twelve percent of KRAS negative colorectal cancer samples showed BRAF gene mutation. Considering that 42% of samples have a KRAS mutation, 54% of patients should not respond to therapies with monoclonal antibodies directed against epidermic growth factor (EGFR) pathway.
- Published
- 2013
22. The low-abundance transcriptome reveals novel biomarkers, specific intracellular pathways and targetable genes associated with advanced gastric cancer
- Author
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Carolina, Bizama, Felipe, Benavente, Edgardo, Salvatierra, Ana, Gutiérrez-Moraga, Jaime A, Espinoza, Elmer A, Fernández, Iván, Roa, Guillermo, Mazzolini, Eduardo A, Sagredo, Manuel, Gidekel, and Osvaldo L, Podhajcer
- Subjects
Reverse Transcriptase Polymerase Chain Reaction ,Gene Expression Profiling ,Blotting, Western ,Antineoplastic Agents ,Adenocarcinoma ,Real-Time Polymerase Chain Reaction ,DNA-Binding Proteins ,Immunoenzyme Techniques ,Alcohol Oxidoreductases ,Cell Movement ,Gastric Mucosa ,Stomach Neoplasms ,Tissue Array Analysis ,Subtraction Technique ,Biomarkers, Tumor ,Tumor Cells, Cultured ,Humans ,Connectin ,Laminin ,RNA, Messenger ,RNA, Small Interfering ,Cell Proliferation ,Oligonucleotide Array Sequence Analysis ,Signal Transduction - Abstract
Studies on the low-abundance transcriptome are of paramount importance for identifying the intimate mechanisms of tumor progression that can lead to novel therapies. The aim of the present study was to identify novel markers and targetable genes and pathways in advanced human gastric cancer through analyses of the low-abundance transcriptome. The procedure involved an initial subtractive hybridization step, followed by global gene expression analysis using microarrays. We observed profound differences, both at the single gene and gene ontology levels, between the low-abundance transcriptome and the whole transcriptome. Analysis of the low-abundance transcriptome led to the identification and validation by tissue microarrays of novel biomarkers, such as LAMA3 and TTN; moreover, we identified cancer type-specific intracellular pathways and targetable genes, such as IRS2, IL17, IFNγ, VEGF-C, WISP1, FZD5 and CTBP1 that were not detectable by whole transcriptome analyses. We also demonstrated that knocking down the expression of CTBP1 sensitized gastric cancer cells to mainstay chemotherapeutic drugs. We conclude that the analysis of the low-abundance transcriptome provides useful insights into the molecular basis and treatment of cancer.
- Published
- 2013
23. [KRAS gene mutation in colorectal cancer]
- Author
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Iván, Roa, Tamara, Sánchez, Alejandro, Majlis, and Kurt, Schalper
- Subjects
Adult ,Male ,Rectal Neoplasms ,DNA Mutational Analysis ,Adenocarcinoma ,Middle Aged ,Proto-Oncogene Proteins p21(ras) ,Young Adult ,Proto-Oncogene Proteins ,Colonic Neoplasms ,Mutation ,ras Proteins ,Humans ,Female ,Chile ,Codon ,Polymorphism, Restriction Fragment Length ,Aged - Abstract
KRAS oncogene is involved in colorectal carcinogenesis in 22 to 45% of cases.To determine the frequency, types and distribution of KRAS mutations in colorectal cancer.KRAS mutations studies were carried out in primary tumors and metastases of colo-rectal cancer from 56 women aged 60 ± 14 years and 53 men aged 61 ± 11 years. Formalin fixed and paraffin embedded tissue samples were evaluated using RFLP (Restriction Fragment Length Polymorphism) and direct sequencing.Primary tumors were located in the colon and rectum in 82 (75.2%) and 24 cases (20%), respectively. In three cases the extraction site of the tumor sample was unknown. In 46 cases (42.2%) KRAS mutations were demonstrated. The main point mutations were located in codon 12 (80.4%), G12D (39.1%), G12V (24.2%), G12S (6.5%), G12A (4.3%); G12C (4.3%), G12R (2.1%) and 19.6% at codon 13 (G13D). No differences were demonstrated in the frequency and distribution of mutations by gender, age, primary versus metastatic tumors or tumor location.In this series, 42% of colorectal cancer tissue samples had KRAS mutations. Their frequency and distribution are similar to those reported in the literature, except for G12C mutation.
- Published
- 2013
24. [Quality of DNA from archival pathological samples of gallbladder cancer]
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Iván, Roa, Gonzalo, de Toro, Tamara, Sánchez, Jeannie, Slater, Anne Marie, Ziegler, Anakaren, Game, Leonardo, Arellano, Kurt, Schalper, and Xabier, de Aretxabala
- Subjects
Quality Control ,Sample Size ,Humans ,Cholecystectomy ,Gallbladder Neoplasms ,DNA, Neoplasm ,Pathology Department, Hospital ,Chile ,Nucleic Acid Amplification Techniques ,Polymerase Chain Reaction - Abstract
The quality of the archival samples stored at pathology services could be a limiting factor for molecular biology studies.To determine the quality of DNA extracted from gallbladder cancer samples at different institutions.One hundred ninety four samples coming from five medical centers in Chile, were analyzed. DNA extraction was quantified determining genomic DNA concentration. The integrity of DNA was determined by polymerase chain reaction amplification of different length fragments of a constitutive gene (β-globin products of 110, 268 and 501 base pairs).The mean DNA concentration obtained in 194 gallbladder cancer samples was 48 ± 43.1 ng/µl. In 22% of samples, no amplification was achieved despite obtaining a mean DNA concentration of 58.3 ng/ul. In 81, 67 and 22% of samples, a DNA amplification of at least 110, 268 or 501 base pairs was obtained, respectively. No differences in DNA concentration according to the source of the samples were demonstrated. However, there were marked differences in DNA integrity among participating centers. Samples from public hospitals were of lower quality than those from private clinics.Despite some limitations, in 80% of cases, the integrity of DNA in archival samples from pathology services in our country would allow the use of molecular biology techniques.
- Published
- 2013
25. Ports: Definition and study of types, sizes and business models
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Beatriz Amante García, María Goretti, Iván Roa Perera, Yessica Peña, Universitat Politècnica de Catalunya. Departament de Projectes d'Enginyeria, Universitat Politècnica de Catalunya. GIIP - Grup de Recerca en Enginyeria de Projectes: Disseny i Sostenibilitat, and Universitat Politècnica de Catalunya. GIIP - Grup de Recerca en Enginyeria de Projectes: Disseny, Sostenibilitat i Comunicació
- Subjects
Ports ,lcsh:T55.4-60.8 ,Harbors -- Aspectes econòmics ,Ports -- Direcció i administració ,Process (engineering) ,Strategy and Management ,media_common.quotation_subject ,Logística naval ,lcsh:Business ,Business model ,types of ports ,Ports -- Gestió ,Industrial and Manufacturing Engineering ,lcsh:Social Sciences ,Management Models ,concessions ,Order (exchange) ,ddc:650 ,Economics ,lcsh:Industrial engineering. Management engineering ,Concessions ,Ports -- Aspectes econòmics ,Market share ,Marketing ,Harbors -- Management ,Recreation ,Industrial organization ,media_common ,lcsh:Commerce ,Types of ports ,ports ,Harbors--Management ,load ,Port (computer networking) ,lcsh:H ,lcsh:HF1-6182 ,Enginyeria civil::Enginyeria hidràulica, marítima i sanitària::Ports i costes [Àrees temàtiques de la UPC] ,Service (economics) ,Business logistics ,Load ,Loading and unloading ,Economia i organització d'empreses::Direcció d'operacions::Modelització de transports i logística [Àrees temàtiques de la UPC] ,lcsh:HF5001-6182 ,Economia i organització d'empreses::Economia sectorial [Àrees temàtiques de la UPC] ,management models ,Tourism - Abstract
Purpose: In the world today there are thousands of port facilities of different types and sizes, competing to capture some market share of freight by sea, mainly. This article aims to determine the type of port and the most common size, in order to find out which business model is applied in that segment and what is the legal status of the companies of such infrastructure.Design/methodology/approach: To achieve this goal, we develop a research on a representative sample of 800 ports worldwide, which manage 90% of the containerized port loading. Then you can find out the legal status of the companies that manage them.Findings: The results indicate a port type and a dominant size, which are mostly managed by companies subject to a concession model.Research limitations/implications: In this research, we study only those ports that handle freight (basically containerized), ignoring other activities such as fishing, military, tourism or recreational.Originality/value: This is an investigation to show that the vast majority of the studied segment port facilities are governed by a similar corporate model and subject to pressure from the markets, which increasingly demand efficiency and service. Consequently, we tend to concession terminals to private operators in a process that might be called privatization, but in the strictest sense of the term, is not entirely realistic because the ownership of the land never ceases to be public
- Published
- 2013
26. Teneurin protein family: an emerging role in human tumorigenesis and drug resistance
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Bernd Wollscheid, Alejandro H. Corvalan, Iván Roa, Jorge Brañes, and Annemarie Ziegler
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Teneurin ,Cancer Research ,Membrane Glycoproteins ,biology ,Protein family ,EMX2 ,Tenascin ,Nerve Tissue Proteins ,Drug resistance ,medicine.disease_cause ,ZIC1 ,Gene Expression Regulation, Neoplastic ,FGF8 ,Cell Transformation, Neoplastic ,Oncology ,Drug Resistance, Neoplasm ,Cell Line, Tumor ,biology.protein ,medicine ,Cancer research ,Humans ,Carcinogenesis - Abstract
Using a chemoproteomic strategy, we recently demonstrated the expression of teneurin-2, a transmembrane glycoprotein, in the majority of malignant mesothelioma cell lines. This finding was unexpected since no formally organized evidence existed to implicate teneurins in human malignancy. For this reason, here we provide a comprehensive review on the expression of teneurins in human tumors and cell lines. Current evidence supports the aberrant expression of teneurins in various tumor types, their involvement in cancer-related regulatory networks, and their potential participation in drug resistance. Structural attributes of teneurins could enable the detection of shedded forms in body fluids for clinical applications.
- Published
- 2012
27. ERCC1 (excision repair cross-complementing 1) expression in pT2 gallbladder cancer is a prognostic factor
- Author
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Iván, Roa, Xabier, de Aretxabala, Soledad, Lantadilla, and Sergio, Munoz
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Aged, 80 and over ,Male ,Protein Array Analysis ,Kaplan-Meier Estimate ,Middle Aged ,Endonucleases ,Prognosis ,Immunohistochemistry ,DNA-Binding Proteins ,Case-Control Studies ,Humans ,Female ,Gallbladder Neoplasms ,Chile ,Aged ,Neoplasm Staging - Abstract
Gallbladder cancer (GBC) is the main cause of death by malignant tumour in women in Chile. There is no information regarding the role of excision repair cross-complementing group 1 (ERCC1) in GBC. Our aim is to determine the expression and significance of ERCC1 as a prognostic factor in GBC. Tissue microarrays were prepared using 200 surgically resected GBCs and 50 non-malignant gallbladders as controls. In 190 cases, ERCC1 was determined by immunohistochemistry. The correlation between ERCC1 expression and GBC pathological characteristics and patient survival were analysed. Ninety-five percent of the non-malignant gallbladder epithelia showed intense and diffuse ERCC1 expression. GBC cases showed ERCC1 expression in the tumour cells in 100/190 (53%) cases. The best differentiated tumours showed significantly greater expression than the less differentiated (p0.05). Patients with ERCC1-positive status with subserosal carcinomas (pT2) had significantly better survival than ERCC1-negative patients at 20 and 60 months of follow-up (p=0.005), and the probability of dying was 6 times lower for ERCC1-positive than for ERCC1-negative patients. Our preliminary results show that chole-cystectomised patients with GBC in stage pT2 and with ERCC1 expression have significantly better survival than patients at the same stage that did not present ERCC1 expression.
- Published
- 2010
28. [Association between cholesterolosis and gallbladder cancer]
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Iván, Roa, Xabier, de Aretxabala, Gilda, Ibacache, and Sergio, Muñoz
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Adenoma ,Male ,Cholelithiasis ,Humans ,Female ,Gallbladder Neoplasms ,Middle Aged ,Sex Distribution ,Epidemiologic Methods - Abstract
Cholesterolosis is frequently observed in cholecystectomies performed for lithiasis or chronic cholecystitis.To determine the degree of association between cholesterolosis and gallbladder cancer.In a prospective study of gallbladder cancer, all gallbladders obtained during cholecystectomies were processed for pathological study, following a special protocol. As part of this study, 23,304 surgical samples obtained between 1993 and 2002 were studied, looking for a relationship between cholesterolosis and chronic cholecystitis, adenomas, dysplasia and gallbladder cancer.Seventy nine percent of patients were women. Cholesterolosis was observed in 3123 cases (13.4%). Cholesterolosis was more common in women (14.2%) than in men (10.2%9) (p0.001). In the same period, 29 patients were diagnosed with adenomas (0.12%), 179 cases with dysplasia not associated with gallbladder cancer (0.8%) and 739 gallbladder cancer (3.2%). The frequency of cholesterolosis was 13.8% in chronic cholecystitis, 13.7% in adenomas, 12.1% in dysplasias and 1.35% in patients with gallbladder cancer (p0.01). Of the thirteen cases with gallbladder cancer and cholesterolosis, 10 were early gallbladder carcinomas. Patients with cholesterolosis were 9.2 times less likely td have cancer than those who did not have cholesterolosis.Cholesterolosis has a strong negative association with gallbladder cancer.
- Published
- 2010
29. Ictericia obstructiva secundaria a migración de fragmentos de hepatocarcinoma a la vía biliar
- Author
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Gabriela Rodríguez M, Horacio Ríos R, Roberto Humeres A, Juan Hepp K, Paulina Balbontín M, Rodolfo Armas M, Iván Roa E, and Claudio Navarrete G
- Subjects
Curative resection ,medicine.medical_specialty ,Hepatocarcinoma ,Cirrhosis ,Common bile duct ,Bile duct ,business.industry ,vía biliar ,urologic and male genital diseases ,medicine.disease ,Gastroenterology ,medicine.anatomical_structure ,Hepatocellular carcinoma ,Internal medicine ,medicine ,Surgery ,Tumor growth ,Obstructive jaundice ,business ,Infiltration (medical) ,ictericia obstructiva - Abstract
Obstructive jaundice secondary to hepatocellular carcinoma fragments migrated to common bile duct Obstructive jaundice is a rare presentation of hepatocellular carcinoma (HC), and when it occurs, usually is due to progressive damage from cirrhosis, or extensive tumor infiltration. Tumor growth through the bile duct is being described with increasing frequency as a cause of obstructive jaundice. Rarely, it may be hepa- tocarcinoma fragments that migrate to the bile duct, obstructing it. We present a case of obstructive jaundice due to migration of fragments of hepatocellular carcinoma to the bile duct in a patient treated 7 years before, for an HC with a curative resection.
- Published
- 2010
30. [p53 and p27 gene expression in subserosal gallbladder carcinoma]
- Author
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Iván, Roa E, Soledad, Lantadilla H, Gilda, Ibacache S, and Xabier, de Aretxabala U
- Subjects
Male ,Serous Membrane ,Carcinoma ,Biomarkers, Tumor ,Humans ,Female ,Gallbladder Neoplasms ,Middle Aged ,Tumor Suppressor Protein p53 ,Prognosis ,Cyclin-Dependent Kinase Inhibitor p27 ,Aged - Abstract
Subserosal carcinoma is the stage that presents the greatest difficulty in the diagnosis therapeutic handling and prognosis evaluation.To study the expression of p53 and p27 genes in subserosal gallbladder cancer.One hundred twenty seven tissue samples of subserosal gallbladder cancer (coming from 112 females aged 62+/-13 years and 15 men aged 67+/-17 years) and 50 control samples were selected to construct tissue arrays. p53 and p27 genes were determined by immunohistochemistry.Thirty eight percent of tumors were not detected at the macroscopic examination, 52% and 17% had lymph node and blood vessel involvement, respectively. Fifty six and 46% were positive for p53 and p27, respectively. No association between the expression of both genes and gender, degree of differentiation, lymph node or blood vessel involvement, was observed. Overall five years actuarial survival was 32%. Patients with positive or negative p53 expression had a 22% and 53% survival, respectively (p=0.05). No association between survival and p27 expression was observed.p53 gene expression is a prognostic factor for subserosal gallbladder cancer.
- Published
- 2009
31. [Immunohistochemical expression of Ki-67 as a marker of proliferation in gallbladder mucosa samples with or without cancer]
- Author
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Iván, Roa E, Xabier, Elorza D, Soledad, Lantadilla H, Gilda, Ibacache S, and Xabier de, Aretxabala U
- Subjects
Male ,Ki-67 Antigen ,Mucous Membrane ,Case-Control Studies ,Biomarkers, Tumor ,Humans ,Female ,Gallbladder Neoplasms ,Middle Aged ,Cell Proliferation - Abstract
There is paucity of knowledge on the proliferative features of normal or chronically inflamed gallbladder and the mechanisms of development of gallbladder cancer.To study the proliferation features of non tumoral gallbladder mucosa through the expression of Ki-67 antigen in tissue micro array analysis.The immunohystochemical expression of Ki-67 in tissue micro array was studied in 96 samples of non tumoral gallbladder mucosa (coming from 74 females aged 45+/-16 years and 22 males aged 53+/-16 years) and 102 samples of gallbladder cancer (coming from 84 females aged 62+/- 14 years and 18 males aged 70+/- 13 years).The staining index of Ki-67 expression was 19+/-25% (range 096-8996) in samples of non tumoral mucosa and 46+/-29% (range 396-9896) in gallbladder cancer (p0.01). Ki-67 was expressed in less than 10% of epithelial cells in 55% of non tumoral mucosa samples and 6% of gallbladder cancer samples. Seventy five percent of gallbladder cancer samples had a staining index of more than 20%. An expression of Ki-67 over 20% or 50% was observed in 25% and 15% of non tumoral mucosa samples, respectively.Non tumoral gallbladder mucosa samples have a high proliferation index, measured using Ki-67 immunohystochemical expression. There is a group of samples with cellular hyper-proliferation that maybe related to the pathogenesis of gallbladder cancer.
- Published
- 2009
32. [Natural history of gallbladder cancer. Analysis of biopsy specimens]
- Author
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Iván, Roa E, Sergio, Muñoz N, Gilda, Ibacache S, and Xabier de, Aretxabala U
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Male ,Mucous Membrane ,Time Factors ,Biopsy ,Carcinoma ,Disease Progression ,Gallbladder ,Humans ,Female ,Gallbladder Neoplasms ,Middle Aged ,Precancerous Conditions - Abstract
There is scarcity of knowledge about the development of gallbladder cancer.To study the features of development and progression of gallbladder cancer.Review of histopathological studies of gallbladder obtained in 25,971 cholecytectomies performed in patients aged 45+/- 16 years, 79% females, between 1993 and 2004. Among these, 210 had a dysplasia not associated to cancer and 1,039 had a gallbladder cancer Clinical and morphological parameters of preneoplastic and neoplastic lesions were analyzed. Ninety five percent of patients were followed.All cases of dysplasia were incidental findings. Metaplasia, dysplasia and carcinoma in situ were present in the adjacent mucosa in 66%, 81% y 69% of gallbladder carcinomas, respectively. Twenty five percent of gallbladders studied were carcinomas (mucous carcinoma in 18% and muscular carcinoma in 7%). Ninety two percent of cases had chronic inflammation in the gallbladder wall. Seventy two percent of mucous carcinomas were not detected macroscopically Five years survival of mucous carcinoma was 92%. There was an association between the intensity of the lesion and the age of the patients. The age difference between chronic cholecystitis and gallbladder cancer was 11 years for women and nine for men.From a morphological standpoint, the period in which a dysplasia becomes a carcinoma is approximately 10 years.
- Published
- 2009
33. Carcinoma subseroso de la vesícula biliar (pT2): Valor pronóstico de la expresión de los genes supresores de tumores p53 y p27 en matrices de tejidos
- Author
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Xabier de Aretxabala U, Gilda Ibacache S, Iván Roa E, and Soledad Lantadilla H
- Subjects
Macroscopic examination ,Gynecology ,medicine.medical_specialty ,Pathology ,business.industry ,Serous membrane ,General Medicine ,medicine.disease ,Actuarial survival ,medicine.anatomical_structure ,Carcinoma ,medicine ,business ,Lymph node ,P53 expression - Abstract
Thirty eight percent oftumors were not detected at the macroscopic examination, 52% and 17% had lymph node and bloodvessel involvement, respectively. Fifty six and 46% were positive for p53 and p27, respectively. Noassociation between the expression of both genes and gender, degree of differentiation, lymph node orblood vessel involvement, was observed. Overall five years actuarial survival was 32%. Patients withpositive or negative p53 expression had a 22% and 53% survival, respectively (p =0.05). No associationbetween survival and p27 expression was observed.
- Published
- 2009
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34. Desde la displasia hasta el cáncer de la vesícula biliar
- Author
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Sergio Muñoz N, Xabier de Aretxabala U, Iván Roa E, and Gilda Ibacache S
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Pathology ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Carcinoma in situ ,Gallbladder ,Cancer ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Dysplasia ,Carcinoma ,Medicine ,Cholecystectomy ,Gallbladder Neoplasm ,Gallbladder cancer ,business - Abstract
Background: There is scarcity of knowledge about the development of gallbladder cancer. Aim: To study the features of development and progression of gallbladder cancer. Material and methods: Review of histopathological studies of gallbladder obtained in 25,971 cholecytectomies performed in patients aged 45± 16 years, 79% females, between 1993 and 2004. Among these, 210 had a dysplasia not associated to cancer and 1,039 had a gallbladder cancer Clinical and morphological parameters of preneoplastic and neoplastic lesions were analyzed. Ninety five percent of patients were followed. Results: All cases of dysplasia were incidental findings. Metaplasia, dysplasia and carcinoma in situ were present in the adjacent mucosa in 66%, 81% y 69% of gallbladder carcinomas, respectively. Twenty five percent of gallbladders studied were carcinomas (mucous carcinoma in 18% and muscular carcinoma in 7%). Ninety two percent of cases had chronic inflammation in the gallbladder wall. Seventy two percent of mucous carcinomas were not detected macroscopically Five years survival of mucous carcinoma was 92%. There was an association between the intensity of the lesion and the age of the patients. The age difference between chronic cholecystitis and gallbladder cancer was 11 years for women and nine for men. Conclusions: From a morphological standpoint, the period in which a dysplasia becomes a carcinoma is approximately 10years.
- Published
- 2009
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35. Proliferación celular en la mucosa de la vesícula biliar no tumoral en colecistitis crónicas litiásicas. Expresión de Ki-67 en matrices de tejidos
- Author
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Xabier Elorza D, Iván Roa E, Gilda Ibacache S, Xabier de Aretxabala U, and Soledad Lantadilla H
- Subjects
Pathology ,medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Gallbladder ,medicine ,General Medicine ,Gallbladder Neoplasm ,Gallbladder cancer ,business ,medicine.disease ,Molecular biology ,Staining - Abstract
29% (range 3%-98%) in gallbladdercancer (p
- Published
- 2009
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36. [Cystic tumors of the pancreas]
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Xabier, de Aretxabala, Iván, Roa, Jorge, León, and Fernando, Maluenda
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Adult ,Cholangiopancreatography, Endoscopic Retrograde ,Pancreatic Neoplasms ,Adenocarcinoma, Papillary ,Cholangiopancreatography, Magnetic Resonance ,Humans ,Female ,Middle Aged ,Pancreatic Cyst ,Tomography, X-Ray Computed ,Adenocarcinoma, Mucinous ,Aged - Abstract
Cystic tumors of the pancreas are diagnosed with increasing frequency. The main problems associated with their diagnosis are to determine if they are benign or malignant and to decide their surgical excision or clinical follow-up, since these tumors can be benign, potentially malignant or malignant. Imaging techniques such as CT scan, magnetic resonance and endoscopic ultrasonography are the key procedures that must be performed before adopting a final therapeutic decision. However, 10% of cystic lesions are unable to be categorized even after thorough imaging evaluation. We analyze the characteristics of the more common cystic pancreatic lesions and the means to recognize them.
- Published
- 2008
37. [A pilot experience with a tumor bank]
- Author
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Iván, Roa E and Carmen G, Artigas A
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Cryopreservation ,Male ,Quality Control ,Reverse Transcriptase Polymerase Chain Reaction ,Breast Neoplasms ,Pilot Projects ,Tissue Banks ,Specimen Handling ,Neoplasms ,Humans ,Female ,Tissue Preservation ,Chile ,Nucleic Acid Amplification Techniques - Abstract
Despite having the technical facilities and the knowledge, Chile did not have a tumor bank until recently.To describe the results of the first three years of a tumor bank.All cases stored in a tumor bank from June 2004 to June 2007 were included. Samples were frozen in isopentane, afterwards in liquid nitrogen and finally transferred to freezers at -80 degrees C. Quality controls with DNA and RNA extraction and immunohistochemistry, were per formed.In the study period, 1239 cases were collected and 79% were malignant tumors. In 78% of cases, samples from the tumor and of normal neighboring tissue, were stored. Twenty six percent of samples were from breast cancer and 22% for digestive tumors. Immunohistochemical expression of vimentin was measured in 30 cases and the expression of Ki67 and p53 in 20 cases. Thirteen of 15 breast cancer samples had expression of estrogen receptors. In 30 cases, DNA and RNA extraction was carried out, amplifying B-globin and B-actin. Moreover RNA was extracted from 63 gastric cancer, 30 colon cancer and gallbladder cancer samples, for specific projects.The creation of a tumor bank is feasible, preserving samples of high biological quality.
- Published
- 2008
38. Banco de tumores en Chile, su aporte a la investigación: resultados de un proyecto piloto
- Author
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Iván Roa E and Carmen Gloria Artigas A
- Subjects
Gynecology ,medicine.medical_specialty ,Colorectal cancer ,business.industry ,Gallbladder ,Cancer ,General Medicine ,Nucleic acid amplification technique ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Breast cancer ,medicine ,RNA extraction ,business - Abstract
In the study period, 1239 cases were collected and79% were malignant tumors. In 78% of cases, samples from the tumor and of normal neighaboringtissue, were stored. Twenty six percent of samples were from breast cancer and 22% for digestivetumors. Immunohistochemical expression of vimentin was measured in 30 cases and the expressionof Ki67 an p53 in 20 cases. Thirteen of 15 breast cancer samples had expression of estrogenreceptors. In 30 cases, DNA and RNA extraction was carried out, amplifying s-globin and s-actin.Moreover RNA was extracted from 63 gastric cancer, 30 colon cancer and gallbladder cancersamples, for specific projects.
- Published
- 2008
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39. [Frequency of TEL/AML1 and BCR/ABL fusion genes in children with acute lymphoblastic leukemia]
- Author
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Carmen Gloria, Artigas A, María Elena, Cabrera C, Angélica, Melo A, Eduardo, Páez F, Mónica, Arriagada M, Carmen, Astete A, Iván, Roa E, and Juan Carlos, Roa S
- Subjects
Male ,Adolescent ,Oncogene Proteins, Fusion ,Reverse Transcriptase Polymerase Chain Reaction ,Child, Preschool ,Core Binding Factor Alpha 2 Subunit ,Fusion Proteins, bcr-abl ,Humans ,Infant ,Female ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,Child ,Translocation, Genetic - Abstract
t(12;21) (p12;q22) and t(9;22) (q34;q11) translocations have prognostic significance in acute lymphoblastic leukemia (ALL). The fusion genes TEL/AML1 y BCR/ABL, generated by these translocations, can be easily detected using molecular biology technique.To study the frequency of TEL/AML1 y BCR/ABL fusion genes in children with ALL.Fifty-six children with ALL (age range 1 month- 14 years) were studied, thirty-eight from our Temuco Hospital and 18 from the Metropolitan Region. TEL/AML1 y BCR/ABL fusion genes were detected in bone marrow samples using a reverse transcriptase nested polymerase chain reaction (RT-PCR).TEL/AML 1 and BCR/ABL fusion gene transcripts were detected in 13 (23%) and 2 (4%) children, respectively. No differences in survival were observed between children with positive or negative transcripts for TEL/AML1 fusion gene. However, those positive for BCR/ABL fusion gene, had a significantly lower survival.The frequency of TEL/AML1 and BCR/ABL fusion gene transcripts in these children with ALL is similar to that described by other authors.
- Published
- 2007
40. Inestabilidad microsatelital en lesiones preneoplásicas y neoplásicas del cuello uterino: Correlación con el genotipo del virus papiloma humano
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Juan Carlos Roa S, Ricardo Martínez S, Sonia Montenegro, Iván Roa E, Angélica Melo A, Italo Capurro V, and Gilda Ibacache S
- Subjects
biology ,medicine.diagnostic_test ,business.industry ,PAPILLOMAVIRUS HUMAN ,Microsatellite instability ,General Medicine ,biology.organism_classification ,medicine.disease ,Virology ,Molecular biology ,Restriction fragment ,Viral genetics ,Biopsy ,Genotype ,biology.protein ,Medicine ,Papillomaviridae ,Dna viral ,business - Abstract
Biopsy samples of cervical lesions were studied. Sixteen hadlow grade lesions, 22 had high grade lesions and 28 had an epidermoid cancer. Viral types wereidentified with polymerase chain reaction, dot-blot hybridization and restriction fragment lengthpolymorphism. MSI was determined using a panel of eight highly informative microsatellites.
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- 2007
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41. [Osteonecrosis associated with the use of biphosphonates: Case report]
- Author
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Timoleón, Anguita C, Jaime, Agurto P, Iván, Roa E, and German, Laissle C
- Subjects
Aged, 80 and over ,Male ,Bone Density Conservation Agents ,Diphosphonates ,Imidazoles ,Osteonecrosis ,Humans ,Pamidronate ,Multiple Myeloma ,Zoledronic Acid ,Jaw Diseases - Abstract
Biphosphonates reduce the risk of skeletal events and are currently part of standards of therapy in myeloma. Recently, zoledronate and pamidronate have been linked to osteonecrosis of the jaw, specially after surgical dental procedures. We report a 84 year-old man with multiple myeloma who developed spontaneous osteonecrosis of both jaws, after 36 months of therapy with zoledronate with a cumulative dose of 136 mg. We discuss the pathogenic mechanisms, and review the recommendations on prevention and management of this new complication for neoplastic patients under prolonged therapy with biphosphonates.
- Published
- 2006
42. [Immunohistochemical expression of the E-cadherin-catenin complex in gastric cancer]
- Author
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Pablo, Guzmán, Juan, Araya, Miguel, Villaseca, Iván, Roa, Angélica, Melo, Sergio, Muñoz, and Juan, Roa
- Subjects
Male ,Kaplan-Meier Estimate ,Middle Aged ,Cadherins ,Immunohistochemistry ,Survival Analysis ,Neoplasm Proteins ,Stomach Neoplasms ,Lymphatic Metastasis ,Humans ,Female ,Neoplasm Invasiveness ,Chile ,alpha Catenin ,beta Catenin ,Neoplasm Staging - Abstract
The E-cadherin/catenin complex plays an essential role in the control of epithelial differentiation. Abnormal expression in tumors correlates with histological grade, advanced stage and poor prognosis.To evaluate the expression pattern of E-cadherin/catenin complex in gastric carcinoma and analyze their association with tumor clinicopathological features and patient survival.Inmunohistochemical staining of E-cadherin, alpha and ss-catenin was performed from paraffin specimens of 65 gastric carcinomas.Abnormal expression of E-cadherin, alpha and ss-catenin was demonstrated in 82%, 85% and 88% of gastric carcinomas, respectively. There was a significant correlation between abnormal expression and Lauren pathological classification and depth of infiltration, but not with tumor stage, positive lymph node metastases and survival.Abnormal expression of E-cadherin, alpha and ss-catenin occurs frequently in gastric carcinoma and correlates with histological grade.
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- 2006
43. Frecuencia de los genes de fusión TEL/AML1 y BCR/ABL en pacientes pediátricos con leucemia linfoblástica aguda
- Author
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María Elena Cabrera C, Angélica Melo A, Iván Roa E, Juan Carlos Roa S, Carmen Astete A, Eduardo Páez F, Carmen Gloria Artigas A, and Mónica Arriagada M
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TEL/AML1 Fusion Protein ,Fusion gene ,ABL ,Oncogene Proteins ,hemic and lymphatic diseases ,breakpoint cluster region ,Chromosomal translocation ,General Medicine ,Biology ,neoplasms ,Fusion protein ,Virology ,Molecular biology - Abstract
TEL/AML 1 and BCR/ABL fusion gene transcriptswere detected in 13 (23%) and 2 (4%) children, respectively. No differences in survival wereobserved between children with positive or negative transcripts for TEL/AML1 fusion gene. However,those positive for BCR/ABL fusion gene, had a significantly lower survival.
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- 2006
- Full Text
- View/download PDF
44. Osteonecrosis asociada al uso de bifosfonatos: A propósito de un caso clínico
- Author
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Jaime Agurto P, Timoleón Anguita C, German Laissle C, and Iván Roa E
- Subjects
medicine.medical_specialty ,Diphosphonates ,Cumulative dose ,business.industry ,Dental procedures ,MEDLINE ,Myeloma ,General Medicine ,medicine.disease ,Surgery ,Zoledronic acid ,stomatognathic system ,medicine ,Osteonecrosis of the jaw ,business ,Complication ,Multiple myeloma ,medicine.drug - Abstract
Biphosphonates reduce the risk of skeletal events and are currently part of standards of therapy in myeloma. Recently, zoledronate and pamidronate have been linked to osteonecrosis of the jaw, specially after surgical dental procedures. We report a 84 year-old man with multiple myeloma who developed spontaneous osteonecrosis of both jaws, after 36 months of therapy with zoledronate with a cumulative dose of 136 mg. We discuss the pathogenic mechanisms, and review the recommendations on prevention and management of this new complication for neoplastic patients under prolonged therapy with biphosphonates.
- Published
- 2006
- Full Text
- View/download PDF
45. Expresión inmunohistoquímica del complejo E-caderina-catenina en cáncer gástrico: Relación con variables clínico-morfológicas y sobrevida de pacientes
- Author
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Iván Roa E, Miguel Villaseca H, Pablo Guzmán G, Juan Araya O, Sergio Muñoz N, Angélica Melo A, and Juan Carlos Roa S
- Subjects
Alpha catenin ,Stomach neoplasms ,Beta catenin ,E-cadherin ,General Medicine ,Biology ,Molecular biology - Abstract
Background: The E-cadherin/catenin complex plays an essential role in the control of epithelial differentiation. Abnormal expression in tumors correlates with histological grade, advanced stage and poor prognosis. Aim: To evaluate the expression pattern of E-cadherin/catenin complex in gastric carcinoma and analyze their association with tumor clinicopathological features and patient survival. Material and Methods: Inmunohistochemical staining of E-cadherin, alpha and ß-catenin was performed from paraffin specimens of 65 gastric carcinomas. Results: Abnormal expression of E-cadherin, alpha and ß-catenin was demonstrated in 82%, 85% and 88% of gastric carcinomas, respectively. There was a significant correlation between abnormal expression and Lauren pathological classification and depth of infiltration, but not with tumor stage, positive lymph node metastases and survival. Conclusion: Abnormal expression of E-cadherin, alpha and ß-catenin occurs frequently in gastric carcinoma and correlates with histological grade (Rev Méd Chile 2006; 134: 1002-9).
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- 2006
46. [Frequency of K-ras mutation in biliary and pancreatic tumors]
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Juan Carlos, Roa, Leonardo, Anabalón, Oscar, Tapia, Angélica, Melo, Xabier, de Aretxabala, and Iván, Roa
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Adult ,Aged, 80 and over ,Male ,Carcinoma ,Middle Aged ,Polymerase Chain Reaction ,Survival Analysis ,Pancreatic Neoplasms ,Genes, ras ,Sex Factors ,Mutation ,Humans ,Female ,Gallbladder Neoplasms ,Codon ,Polymorphism, Restriction Fragment Length ,Aged - Abstract
The ras gene family (H-ras, N-ras and K-ras) are oncogenes that mutate frequently in human cancer, specially in tumors of the biliary tract and pancreas.To determine the frequency of K-ras gene codon 12 mutation in pancreatic and biliary tumors.Samples of 35 gallbladder, 15 ampulla of Vater, 10 biliary tract and 9 pancreatic tumors, were analyzed. The tumor tissue was microdissected from paraffin embedded biopsies. The mutation was detected by a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).Overall, 46% of samples had K-ras gene mutations. Mutation frequency was 80, 56, 50 and 29% for ampulla of Vater, pancreatic, biliary tract and gallbladder tumors, respectively. When compared with the rest, gallbladder tumors had a significantly lower frequency of the mutation. Median survival for biliary tract tumors was 6 months, compared with 65 months for gallbladder tumors (p0.05).Gallbladder carcinoma had the lower frequency of K-ras mutation, when compared with pancreatic, biliary tract and ampulla of Vater tumors.
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- 2006
47. Promoter methylation profile in gallbladder cancer
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Sergio Muñoz, Juan Carlos Roa, Leonardo Anabalón, Iván Roa, Juan Carlos Araya, Xavier de Aretxabala, Oscar Tapia, Barbara G. Schneider, and Angélica Melo
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Adult ,Male ,Adenomatous Polyposis Coli Protein ,Biology ,Adenocarcinoma ,medicine.disease_cause ,CDH1 ,FHIT ,CDKN2A ,Antigens, CD ,medicine ,Humans ,Genetic Predisposition to Disease ,Gallbladder cancer ,Chile ,Promoter Regions, Genetic ,Cyclin-Dependent Kinase Inhibitor p16 ,Adaptor Proteins, Signal Transducing ,Aged ,Aged, 80 and over ,Gastroenterology ,Nuclear Proteins ,Promoter ,Methylation ,DNA, Neoplasm ,DNA Methylation ,Middle Aged ,medicine.disease ,Cadherins ,Immunohistochemistry ,Survival Analysis ,Acid Anhydride Hydrolases ,Neoplasm Proteins ,Gene Expression Regulation, Neoplastic ,DNA methylation ,Cancer research ,biology.protein ,Female ,Gallbladder Neoplasms ,Carcinogenesis ,Carrier Proteins ,MutL Protein Homolog 1 ,Follow-Up Studies - Abstract
Methylation in the promoter region of genes is an important mechanism of inactivation of tumor suppressor genes. Our objective was to analyze the methylation pattern of some of the genes involved in carcinogenesis of the gallbladder, examining the immunohistochemical expression of proteins, clinical features, and patient survival time.Twenty cases of gallbladder cancer were selected from the frozen tumor bank. The DNA extracted was analyzed by means of a methylation-specific polymerase chain reaction test for the CDKN2A (p16), MLH1, APC, FHIT, and CDH1 (E-cadherin) genes. Morphological and clinical data and follow-up information were obtained.All cases were in an advanced stage: histologically moderate or poorly differentiated tumors (95%). Methylation of the promoter area of genes was observed in 5%, 20%, 30%, 40%, and 65% of cases, and an altered immunohistochemical pattern (AIP) in 5%, 35%, 21%, 25%, and 66% for the MLH1, CDKN2A, FHIT, APC, and CDH1 genes, respectively. The Kappa concordance index between methylation of the promoter area and AIP for the MLH1 and CDH1 genes was very high (K0.75) and substantial for APC (K0.45). No correlation was found between survival time and the methylation of the genes studied.The high frequency of gene methylation (with the exception of MLH1) and the high agreement between AIP and methylation of the gene promoter area for the MLH1, APC, and CDH1 genes suggest that the inactivation of tumor suppressor genes and of the genes related to the control of cellular proliferation through this mechanism is involved in gallbladder carcinogenesis.
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- 2006
48. Gallstones and gallbladder cancer-volume and weight of gallstones are associated with gallbladder cancer: a case-control study
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Iván Roa, Juan Carlos Roa, Sergio Muñoz, Gilda Ibacache, Juan Carlos Araya, and Xabier de Aretxabala
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Male ,medicine.medical_specialty ,Gallbladder Dysplasia ,medicine.medical_treatment ,Gallstones ,Body weight ,Gastroenterology ,Risk Factors ,Internal medicine ,Cholecystitis ,Medicine ,Humans ,Cholecystectomy ,Obesity ,Risk factor ,Gallbladder cancer ,Analysis of Variance ,business.industry ,Gallbladder ,Case-control study ,General Medicine ,medicine.disease ,medicine.anatomical_structure ,Oncology ,Case-Control Studies ,Chronic Disease ,Regression Analysis ,Surgery ,Female ,Gallbladder Neoplasms ,business - Abstract
Background Gallstones are considered the most important risk factor for gallbladder cancer. Aim To identify differences in the number, weight, volume, and density of gallstones associated with chronic cholecystitis (CC), gallbladder dysplasia (GD), and gallbladder cancer (GBC). Methods A total of 125 cases were selected, of which 93 had gallstones associated with GBC and 31 had gallstones associated with GD. The controls were those with CC, matched by sex and age. The number, weight, volume, and density of these gallstones were examined in order to determine differences and relative cancer risk. Results Number: Multiple gallstones were present in over 76% of cases (GBC and GD) and controls (P = ns). The average number of multiple stones was 21 in GBC versus 14 in controls (P
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- 2006
49. [Promoter methylation profile in gastric cancer]
- Author
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Juan Carlos, Roa, Leonardo, Anabalón, Iván, Roa, Oscar, Tapia, Angélica, Melo, Miguel, Villaseca, and Juan Carlos, Araya
- Subjects
Adult ,Aged, 80 and over ,Male ,Stomach Neoplasms ,Humans ,Female ,Genes, Tumor Suppressor ,DNA Methylation ,Middle Aged ,Promoter Regions, Genetic ,Nucleic Acid Amplification Techniques ,Polymerase Chain Reaction ,Aged - Abstract
Promoter genomic DNA methylation is an important inactivation mechanism of tumor suppressor genes. This genetic-molecular pathway for cancer may separate a subset of patients with different prognoses and eventually different responses to specific therapies.To analyze the methylation pattern of important genes related to different carcinogenic mechanisms in patients with gastric cancer (GC) and the relationship with its morphological features and biological behavior.Forty-seven fresh-frozen GC samples were selected. The methylation-specific PCR (MSP) test was used to analyze promoter methylation status for genes MLH1, CDKN2A (p16), APC, CDH1 (Cadherin E) and FHIT. Follow-up and complete morphological features were obtained for all cases.We found methylation in at least one of the genes studied in 83% of the cases. The frequencies of promoter hypermethylation of MLH1, CDKN2A, APC, CDH1 and FHIT were 31%, 43%, 46%, 80% y 62%, respectively. We found a relationship between APC methylation and good histological differentiation (p =0.03); CDH1 methylation with diffuse type by Lauren and 3 or more metastasic lymph nodes (p0.05); FHIT, CDKN2A and CDH1 methylation and female condition (p0.04). We also found a non-significant relationship between CDKN2A methylation and better survival (p =0.07).The high frequency promoter methylation found confirms its importance in gastric carcinogenesis. The finding of alterations in the methylation pattern of genes studied and its association with prognostic factors is a helpful tool in the search for new criteria in clinical and therapeutic decision making.
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- 2005
50. [Detection of human papilloma virus in cytologic samples or biopsies of the cervix]
- Author
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Angélica, Melo, Iván, Roa, Sonia, Montenegro, Italo, Capurro, and Juan Carlos, Roa
- Subjects
Vaginal Smears ,Paraffin Embedding ,Tissue Fixation ,Biopsy ,DNA, Viral ,Humans ,Female ,Cervix Uteri ,Papillomaviridae ,Polymerase Chain Reaction ,Polymorphism, Restriction Fragment Length ,Globins - Abstract
The DNA quality for the detection and typification of Human Papilloma Virus (HPV) varies according to the type of sample in which it is studied. This may affect the sensitivity and specificity of the method employed.To study the yield and specificity of HPV detection and typification in uterine cervical samples obtained by cervical brushing fresh frozen and formalin fixed tissue.Cytological, fresh frozen and fixed tissue samples from 44 patients (nine with low grade lesions and 35 with high grade lesions) were studied. Nested polymerase chain reaction for genes E6/E7 was used to typify HPV groups as low risk or high risk.Of all the cytological samples obtained by brushing 84% of fixed samples and 43% of fresh frozen samples were positive for HPV. The yields were significantly different when comparing brushing with fixed tissue or fresh frozen tissue and fixed tissue with fresh frozen tissue (p0.05). The frequency of high risk HPV fluctuated from 41% in fresh frozen tissue to 98% in cytological samples. Low risk HPV was detected in 16% of fresh frozen tissue and 68% of cytological samples. A mixed infection was detected in 66%, 41% and 14% of cytological, fresh frozen and fixed tissue samples respectively.Cytological samples obtained by brushing had the highest yield for the detection of cervical infection with HPV.
- Published
- 2005
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