Sample records for UNIDADES DE REACTIVIDAD (reactivity units)
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1

Evaluación externa de los resultados serológicos en los bancos de sangre de Colombia/ External evaluation of serology results in blood banks in Colombia

Beltrán Durán, Mauricio; Ayala Guzmán, Maribel
2003-03-01

Resumen en español OBJETIVO: Analizar los resultados serológicos obtenidos en los bancos de sangre colombianos que participan en el programa externo de calidad (PEC) con el fin de mejorar la calidad del tamizaje de la sangre según los principales marcadores serológicos de enfermedades infecciosas de posible transmisión sanguínea. MÉTODOS: Se evaluó un panel de seis sueros con diferente reactividad y positividad a anticuerpos contra los virus de la inmunodeficiencia humana (VIH) 1-2, (mas) el virus de la hepatitis C (VHC), Trypanosoma cruzi, Treponema pallidum y el virus linfotrópico de células T humanas (HTLV), y contra el antígeno de superficie del virus de la hepatitis B (HBsAg). Las técnicas de tamizaje utilizadas fueron el ensayo de inmunoadsorción enzimática (ELISA), el inmunoensayo enzimático de micropartículas (MEIA) y la hemaglutinación (HA). Se solicitó a los bancos de sangre participantes que aplicaran a los sueros las pruebas que diariamente realizaban para el tamizaje de unidades de sangre y que enviaran los resultados a la Coordinación Nacional de Bancos de Sangre del Instituto Nacional de Salud de Colombia. RESULTADOS: De 46 bancos de sangre que participaron, 43 (93%) devolvieron los resultados en el plazo indicado. La prueba de ELISA fue la más utilizada (83,02%). Se obtuvo un total de 49 (5%) resultados positivos falsos y 12 (3%) resultados negativos falsos. De estos últimos, 50% correspondieron a la detección de la sífilis; 16,7% a la de la enfermedad de Chagas; 16,7% a la de anticuerpos anti-HBc; 8,3% a la de anticuerpos anti-VHC y 8,3% a la del HBsAg. Ochenta por ciento de los resultados discordantes se presentaron en 23 bancos de sangre con un volumen de menos de 6 000 unidades de sangre al año, y 15% en 5 bancos de sangre con un volumen de 6 000 a 12 000 unidades de sangre al año. De los bancos de sangre que recogían más de 12 000 unidades anuales, solo uno notificó tres resultados positivos falsos. No se notificaron resultados negativos falsos. CONCLUSIONES: El porcentaje de resultados negativos falsos (3%) obtenidos durante el PEC puede considerarse elevado, ya que las pruebas que resultan negativas durante el tamizaje de los bancos de sangre no se repiten y la decisión de declarar una unidad de sangre apta para transfusión se basa en ese único resultado. Es preciso revisar minuciosamente los procedimientos para el tamizaje de la sangre, en particular en aquellos centros que tuvieron un desempeño pobre. Resumen en inglés OBJECTIVE: To analyze the serological results found in Colombian blood banks that participate in the external quality program (EQP) of that country's National Institute of Health, in order to improve the quality of the screening of blood for the main serological markers of transfusion-transmitted infectious diseases. METHODS: Each blood bank received a panel of six sera with different reactivity and positivity to hepatitis B surface antigen (HBsAg), as well as to antibodi (mas) es to HIV 1-2, Trypanosoma cruzi (the causative agent of Chagas' disease), Treponema pallidum (the causative agent of syphilis), hepatitis B core (HBc) antigen, hepatitis C virus (HCV), and human T-lymphotropic virus (HTLV). The screening techniques used were enzyme- linked immunosorbent assay (ELISA), microparticle enzyme immunoassay (MEIA), and hemagglutination. With the panel sera, the participating blood banks were asked to apply the same tests that they use on a daily basis to screen blood units and to send their results to the National Blood Banks Unit of the Colombian National Institute of Health. RESULTS: Of the 46 blood banks participating in the EQP, 43 of them (93%) returned their results within the requested timeframe. The ELISA test was the one that was used most often (83.0%). There were a total of 49 (5%) false positive results and 12 (3%) false negative results. Of those 12 false negative results, 6 of them corresponded to the detection of syphilis, 2 to Chagas' disease, 2 to anti-HBc antibodies, 1 to anti-HCV antibodies, and 1 to HBsAg. Eighty percent of the discordant results came from 23 blood banks that each collected fewer than 6 000 units of blood per year, and 15% came from 5 blood banks that collected 6 000 to 12 000 units per year. One of the blood banks that collected more than 12 000 units annually had three false positive results, and none of those larger blood banks had any false positive results. CONCLUSIONS: The percentage of false negative results (3%) found during the EQP can be considered high, since tests that are negative during blood screening are not repeated, and the decision to declare a unit of blood suitable for transfusion is based on that single result. There is a need to thoroughly review the procedures for screening blood in Colombia, particularly at the centers that performed poorly in this EQP exercise.

Scientific Electronic Library Online (Spanish)

2

Control de la infección por Trypanosoma cruzi en donantes de sangre de Colombia, 2003/ Control of infection for the Trypanosoma cruzi in blood donors

Beltrán, Mauricio; Bermúdez, María Isabel; Forero, María Cristina; Ayala, Maribel; Rodríguez, Magda Juliana
2005-12-01

Resumen en español Introducción. La enfermedad de Chagas es un problema de salud pública en Latinoamérica. Después de la vectorial, la segunda fuente de transmisión es la transfusional; en Colombia el tamizaje para este marcador es obligatorio en los bancos de sangre desde 1995. Objetivo. Evaluar el comportamiento de algunas estrategias de control de la infección en donantes y estimar el riesgo transfusional por enfermedad de Chagas. Materiales y métodos. Se analizaron los datos de c (mas) obertura de tamizaje y reactividad para anticuerpos anti- Trypanosoma cruzi; los resultados de los bancos de sangre en el Programa de Evaluación Externa del Desempeño de Serología (PEED) y los reportes de los Laboratorios de Salud Pública sobre pruebas confirmatorias de serología en donantes. Resultados. En 2003, los bancos de sangre del país captaron 482.371 unidades, 99,91% fueron analizadas para anti- T.cruzi, resultando reactivas 0,42%. Casanare presentó la mayor reactividad con 107/1.487 (7,2%), de los cuales se confirmaron como positivos 75. En el PEED participaron 45,5% bancos, la totalidad de los cuales utilizó ELISA para tamizaje; se hallaron 1,1% resultados falsos positivos y ningún falso negativo. En 12 departamentos que analizaron 338.563 unidades para anti- T.cruzi, 1.298 casos fueron notificados como reactivos y 1.108 (85,4%) se confirmaron por la prueba de IFI, registrando una positividad de 0,33%. Conclusiones. Aunque la cobertura del tamizaje llegó a 99,91%, existe aún riesgo de infección por T.cruzi. Los casos de T.cruzi en donantes oscilan entre 0 y 50 por cada mil, y como ya se mencionó, Casanare es el departamento con mayor riesgo de adquirir Chagas transfusional. Los bancos participantes en el PEED no mostraron resultados falsos negativos. Resumen en inglés Introduction. Chagas disease is a public health problem in Latin America. Whereas the primary source of transmission is the insect vector, the second is by blood transfusion. Consequently, in Colombia, screening for trypanosomiasis has been obligatory for blood donors since 1995. Objective. The effectiveness ot current strategies for infection control in donors was evaluated in order to estimate the risk of blood stock contamination with Chagas disease. The screening data (mas) came from the blood banks in the Program of External Evaluation in the Performance of Serology and the reports of the Laboratories of Public Health on confirming donor serology tests. Results. In 2003, 482,371 units of blood were collected in all of Colombia Of these, 99.9% were analyzed for anti-T.cruzi reactivity, with a positives of 0.42% detected. The Casanare Province presented the biggest number of reactive donors 107/1,487 (7.2%), with 75 confirmed positive. In the Program of External Evaluation in the Performance of Serology, 45.5% of all banks participated-all used ELISA for screening of anti-T.cruzi. 1.1% false positives and nofalse negatives were indicated in 12 provinces, where 338,563 units were analyzed for anti- T.cruzi, 1,298 units were reactive and 1,108 (85.4%) were confirmed by the IFI test. This indicated a rate of Chagas positives of 0.33%. Conclusions. Although the analysis covered arrived at 99.9% of the blood units, a small degree of infection risk for T.cruzi still remains. The cases of T.cruzi in donors oscillate between 0 and 50 per thousand. This rate is highest in Casanare with a concomitantly high risk for acquisition of transfusional Chagas. ot show negative false results.

Scientific Electronic Library Online (Spanish)

3

Time to contact for obstacle avoidance

Alenyà Ribas, Guillem; Nègre, Amaury; Crowley, James L.
2009-01-01

Digital.CSIC (Spain)

6

The role played by the reactive alumina content in the alkaline activation of fly ashes

Fernández-Jiménez, Ana; Palomo Sánchez, Ángel; Sobrados, Isabel; Sanz, J.
2006-04-01

Digital.CSIC (Spain)

8

Stratified scree in the Central Spanish Pyrenees: palaeoenvironmental implications

García-Ruiz, José María; Valero-Garcés, Blas L.; González-Sampériz, Penélope; Lorente, Adrián; Martí Bono, Carlos Enrique; Beguería, Santiago; Edwards, Larry
2001-01-01

Digital.CSIC (Spain)

10

Metal-free access to fully substituted skipped diynes. An efficient chemodifferentiating A2BB' 4CR manifold

Tejedor, David; López-Tosco, Sara; González-Platas, Javier; García-Tellado, Fernando
2007-06-09

Digital.CSIC (Spain)

12

Isolation and structural characterization of the milled wood lignin from Paulownia fortunei wood

Rencoret, Jorge; Marques, Gisela; Gutiérrez Suárez, Ana; Nieto, Lidia; Jiménez-Barbero, Jesús; Martínez Ferrer, Ángel Tomás; Río Andrade, José Carlos del
2009-01-01

Digital.CSIC (Spain)

13

High-resolution seismic stratigraphy of the Galicia Bank Region and neighbouring abyssal plains (NW Iberian continental margin)

Ercilla, Gemma; García-Gil, Soledad; Estrada, Ferrán; Vizcaino, A.; Váquez, J. T.; Díaz, S.; Vilas, Federico
2008-03-11

Digital.CSIC (Spain)

14

High-Pressurized Orange Juice Consumption Affects Plasma Vitamin C, Antioxidative Status and Inflammatory Markers in Healthy Humans

Sánchez-Moreno, Concepción; Cano, M. Pilar; Ancos, Begoña de; Plaza, Lucía; Olmedilla, Begoña; Granado Lorencio, Fernando; Martín, Antonio
2003-07-01

Digital.CSIC (Spain)

15

Evolución tectonoestratigráfica de los Catalánides

Anadón Monzón, Pedro; Colombo Piñol, Ferrán; Esteban Cerdà, Mateu; Marzo Carpio, M.; Robles Orozco, Sergio; Santanach, Pere; Solé Sugrañes, Lluís
1979-01-01

Digital.CSIC (Spain)

17

Evaluación de la respuesta a la tuberculina en estudiantes del área de la salud/ Evaluation of the response to tuberculin among university students in the health field

Arbeláez M., María Patricia; Ocampo, María Clara; Montoya, Javier; Jaramillo, Lina María; Giraldo, Paula María; Maldonado, Andrés; Cano, Erica; Andrés Mejía, Óscar; García, Luis F.
2000-10-01

Resumen en español Se realizó un estudio transversal con el fin de evaluar la respuesta a la tuberculina en estudiantes del área de la salud (medicina, odontología, enfermería y bacteriología) en comparación con estudiantes de otras áreas de la Universidad de Antioquia (Medellín, Colombia) en tres niveles, (inicial, intermedio y final) del programa académico. La muestra comprendió 490 estudiantes, 273 del área de la salud y 217 de las otras áreas; la selección se hizo de manera (mas) aleatoria con base en los listados del Departamento de Admisiones y Registros de la Universidad para el segundo semestre de 1998. Se determinó la presencia de cicatriz de vacunación BCG y factores de riesgo de tuberculosis. La tuberculina se evaluó 72 horas después de la aplicación intradérmica de 2 UT de PPD, RT-23. La respuesta a la tuberculina no mostró diferencias por nivel de estudios ni nivel socioeconómico; solo la presencia de cicatriz BCG estuvo significativamente asociada (P=0,007). Estos resultados indican que los estudiantes del área de la salud tienen un contacto reducido con pacientes con tuberculosis o sus muestras durante su formación, lo cual no descarta la tuberculosis como riesgo profesional para el personal de salud. Resumen en inglés A cross-sectional study was done at the University of Antioquia, Medellín, Colombia, to evaluate the response to a tuberculin skin test among students in undergraduate health programs (medicine, odontology, nursing, and bacteriology) as compared to undergraduate students in nonhealth programs. The study included students from the beginning, middle, and end of the university's academic programs. The sample of 490 students included 273 from health programs and 217 from non (mas) health programs. Participants were randomly selected using lists provided by the university registrar, for the second semester of 1998. The presence of a BCG vaccination scar was determined, and all the participants were also questioned about TB-related risk factors. Tuberculin skin test reactivity was evaluated by the size of induration 72 hours after intradermal injection of two tuberculin units of purified protein derivative RT 23. There were no differences in tuberculin reactivity between students from the health programs and from the nonhealth programs, irrespective of the academic level. However, there was a significantly higher proportion of positive skin tests among students with a BCG scar. These results suggest that undergraduate health students do not have extensive contact with TB patients or with clinical samples from such patients. Nevertheless, the results do not rule out TB as an occupational risk for health personnel.

Scientific Electronic Library Online (Spanish)

18

Diferencias de sexo en la prevalencia y severidad de trastornos psiquiátricos en adolescentes de la Ciudad de México/ Sex differences in the prevalence and severity of psychiatric disorders in Mexico City adolescents

Benjet, Corina; Borges, Guilherme; Medina-Mora, María Elena; Méndez, Enrique; Fleiz, Clara; Rojas, Estela; Cruz, Carlos
2009-04-01

Resumen en español Introducción El presente trabajo proporciona datos de la Encuesta Mexicana de Salud Mental Adolescente y tiene el objetivo de estimar las diferencias por sexo de la prevalencia y la severidad en los últimos 12 meses para 17 trastornos psiquiátricos en adolescentes de la Ciudad de México y área metropolitana así como las edades de inicio de dichos trastornos. Material y métodos El diseño de la muestra fue probabilístico y multietápico, ésta estuvo compuesta por (mas) adolescentes entre los 12 y 17 años, residentes del Distrito Federal y área metropolitana. Para ello, se entrevistó a 3005 adolescentes en sus hogares, con una tasa de respuesta de 71 % y se utilizó como instrumento diagnóstico la Entrevista Internacional Diagnóstica Compuesta (WMH-CIDI-A 3.0) aplicada cara a cara, por medio de una computadora portátil, por encuestadores capacitados en los hogares de los participantes. Resultados Los trastornos individuales más frecuentes en ambos sexos fueron las fobias específicas y la fobia social. Para las mujeres, los trastornos más prevalentes en orden decreciente fueron las fobias, la depresión mayor, el trastorno negativista desafiante, la agorafobia sin pánico y la ansiedad por separación. Mientras que en los varones, los trastornos más prevalentes después de las fobias fueron: el trastorno negativista desafiante, el abuso de alcohol y el trastorno disocial. Las mujeres presentaron un mayor número de trastornos y una mayor prevalencia de cualquier trastorno. Los padecimientos con mayor proporción de gravedad fueron los trastornos de ánimo y en menor proporción los trastornos ansiosos. Este patrón fue similar para hombres y mujeres, sin embargo existen diferencias en la proporción de casos graves entre ambos ya que las mujeres tuvieron una mayor proporción de casos de este tipo. Los trastornos que se presentaron en edades de inicio más tempranas fueron los trastornos de ansiedad, seguidos por los trastornos de impulsividad y los trastornos de ánimo. Además los trastornos que se presentaron en edades más tardías fueron los trastornos por uso de sustancias. Las edades de inicio para los trastornos de ansiedad, ánimo y por uso de sustancias son similares entre los sexos, a diferencia de los trastornos de impulsividad en los cuales los hombres tienen edades de inicio más tempranas que las mujeres. Discusión La mayor prevalencia general y severidad de trastornos psiquiátricos en las mujeres comparadas con los varones sugiere que la adolescencia podría ser un periodo de mayor vulnerabilidad para aquellas. Hay teorías biológicas y psicosociales que pretenden explicar la mayor vulnerabilidad de las niñas en la etapa adolescente, entre ellas la teoría de la intensificación del rol de género, la exposición a mayor adversidad y la mayor reactividad del eje hipotálamo-pituitario-adrenal ante el estrés. Los hallazgos de este estudio son relevantes para la práctica clínica así como para la vigilancia epidemiológica en nuestra población ya que sirven para la planificación de servicios y políticas públicas de salud y educación. Resumen en inglés Introduction The first and only nationally representative prevalence estimates of psychiatric disorders in Mexico (the Mexican National Comorbidity Survey) indicate sex differences in the expression of psychopathology and early ages of onset for most disorders, often in the adolescent years. Studies from other countries have shown that sex differences in the pattern of psychopathology vary by life stage, which in part, may be explained by different ages of onset for varyi (mas) ng disorders. These studies also suggest that many of the sex differences in the prevalence of disorders emerge during the adolescent years. However, scarce data is available on the epidemiology of adolescent psychopathology in Mexico, and much less regarding possible sex differences in the patterns of prevalence, severity and ages of onset. The purpose of this report, therefore, is to estimate sex differences in the 12-month prevalence and severity of 17 psychiatric disorders (using DSM-IV diagnostic criteria) as well as ages of onset in adolescents from Mexico City metropolitan area. Materials and methods This article provides data from the Mexican Adolescent Mental Health Survey. This survey has a multistage probability design and is representative of adolescents between 12 and 17 years old who reside in the Mexico City metropolitan area. The final sample included 3 005 adolescents selected from a stratified multistage area probability sample. In all strata, the primary sampling units were census count areas cartographically defined and updated in 2000 by the Mexican National Institute of Statistics, Geography and Informatics (INEGI). Two hundred census count areas were selected with probability proportional to size. Secondary sampling units were city blocks, four of which were selected with probability proportional to size from each census count area. All households within these selected city blocks with adolescents aged 12 to 17 were selected. One eligible member from each of these households was randomly selected using the Kish method of random number charts. The response rate of eligible respondents was 71%. The adolescents were interviewed in their homes by trained lay interviewers using the computerized adolescent version of the World Mental Health Composite International Diagnostic Interview (WHM-CIDI-A 3.0). The average length of the interview was two and a half hours. A verbal and written explanation of the study was given to both parents and adolescents. Interviews were administered only to those for whom signed informed consent from a parent and/or legal guardian were obtained as well as the adolescent agreement. Because of the stratified multistage sampling design, data was subsequently weighted to adjust for differential probabilities of selection and non-response. Post-stratification to the total Mexico City Metropolitan Area adolescent population according to the year 2000 Census in target age and sex ranges were also performed. For prevalence estimates, due to this complex sample design and weighting, estimates of standard errors for proportions were obtained by the Taylor series linearization method using the SUDAAN software. Sex differences were evaluated using Wald χ² tests. Statistical significance was based on two-tailed design tests evaluated at the .05 level of significance. Ages of onset for psychiatric disorders were estimated using discrete time survival analyses with person-years as the unit of analysis which in this article are presented as Kaplan-Meier curves. Results The most prevalent individual disorders in both sexes were specific phobia (15.6% for males, 26.1% for females) and social phobia (10.0% for males, 12.4% for females). For females, the most frequent disorders that follow in magnitude after these two types of phobias are, in decreasing order, major depression (7.6%), oppositional defiant disorder (6.9%), agoraphobia without panic (4.7%) and separation anxiety disorder (3.6%). On the other hand, for males, the most frequent disorders after specific and social phobia are oppositional defiant disorder (3.7%), alcohol abuse (3.4%) and conduct disorder (3.3%). Overall, females reported a larger number of disorders and a greater prevalence of any disorder. With regards to disorder severity, mood disorders have the greatest proportion of severe cases and anxiety disorders the smallest proportion of severe cases. While this pattern is found for both males and females, there are sex differences in severity such that females have a greater proportion of severe cases overall (25.5% were severe cases compared to 18.9% for males). The earliest ages of onset were found in anxiety disorders, followed by impulse control disorders, and mood disorders with substance use disorders having the latest ages of onset. The ages of onset for anxiety, mood and substance use disorders are similar between males and females. However, males developed at earlier ages the onset of impulse control disorders than females, and this is due primarily to oppositional defiant disorder rather than to attention deficit hyperactivity disorder or to conduct disorder. Discussion The greater overall prevalence and severity of psychiatric disorders in adolescent females in comparison to adolescent males suggests that adolescence may be a period of greater vulnerability for females. Our findings with regards to a higher prevalence of mood and anxiety disorders in adolescent females in comparison to males are consistent with those reported in the international literature. However, our findings of more impulse control disorders in females than males are inconsistent with most international reports excepting a study of Finnish adolescents in which adolescent girls reported more internalizing and externalizing disorders than their male counterparts. The greater prevalence of impulse control disorders in our study is due to oppositional defiant disorder, not attention deficit hyperactivity or conduct disorder. The lack of sex differences in substance use disorders is consistent with recent findings in Mexican adolescents which show a narrowing of the sex gap difference in substance use. There are both biological and psychosocial theories which may explain the greater vulnerability in adolescent girls such as gender role intensification and socialization during adolescence; a higher exposure to adversity, stress and negative life events; as well as a greater reactivity of the hypothalamic-pituitary-adrenal axis when confronted with stress. Study limitations include the willingness of participants to disclosure sensitive or potentially embarrassing information as well as potential sex differences in willingness. While females reported more disorders and greater severity of disorders overall, sex differences in response style are not likely, since females reported more of many, but not all disorders. A further limitation is the use of trained lay interviewers instead of clinicians. The development and use of fully structured diagnostic instruments such as the CIDI have greatly helped to tackle this limitation in general population surveys and data suggest that diagnoses provided by these fully structured instruments approximate adequately clinical diagnoses. Keeping in mind these limitations, the results of this study are relevant for clinical practice as well as for the epidemiological surveillance of our population to guide service planning and public health policy.

Scientific Electronic Library Online (Spanish)

19

Decreased Levels of Plasma Vitamin C and Increased Concentrations of Inflammatory and Oxidative Stress Markers After Stroke

Sánchez-Moreno, Concepción; Dashe, John F.; Scott, Tammy; Thaler, David; Folstein, Marshal F.; Martín, Antonio
2004-01-01

Digital.CSIC (Spain)

22

Cinemática y paleoesfuerzos en la zona de falla transcurrente de Jebha-Chrafate (Rif septentrional, Marruecos)

Benmakhlouf, M.; Galindo-Zaldívar, Jesús; Chalouan, Ahmed; Sanz de Galdeano, Carlos; Ahmamou, M.; López-Garrido, A. C.
2005-01-01

Digital.CSIC (Spain)

23

Cenozoic deformational structures on the Galicia Bank Region (NW Iberian continental margin)

Vázquez, Juan T.; Medialdea, Teresa; Ercilla, Gemma; Somoza, Luis; Estrada, Ferrán; Fernández Puga, M. C.; Gallart Muset, Josep; Gràcia i Mont, Eulàlia; Maestro, A.; Sayago, M.
2008-03-11

Digital.CSIC (Spain)