Resumo O objetivo deste trabalho foi avaliar o efeito da salinidade na distribuição de K+ e Na+ e no conteúdo de prolina em cultivares dos capins de Urochloa brizantha e Urochloa decumbens. As plantas foram cultivadas em solução nutritiva e expostas a estresse salino durante nove dias. Foram determinados os comprimentos da parte aérea e das raízes e os conteúdos de prolina, clorofila total, K+ e Na+. O estresse salino reduziu o comprimento da par te aérea da cultivar Marandu, mas não de Xaraés e Basilisk. O conteúdo total de clorofila não foi afetado nas cultivares de U. brizantha, mas aumentou na cultivar Basilisk de U. decumbens. Observou-se acúmulo de prolina em todas as cultivares sob estresse salino, com maior aumento em Marandu. O conteúdo de K+ nos limbos foliares aumentou nas cultivares Marandu e na Basilisk, em condições de estresse. 'Basilisk' apresentou exclusão de Na+ nos tecidos aéreos, enquanto 'Marandu' e 'Piatã', seguidas por 'Xaraés', apresentaram maior acúmulo de Na+ nos limbos foliares. O padrão de distribuição de íons entre as cultivares foi atribuído, principalmente, a diferenças na habilidade para controlar seu transporte da raiz aos tecidos da parte aérea, já que as taxas de absorção foram similarmente afetadas pela salinidade. A tolerância à salinidade em gramíneas do gênero Urochloa está associada à exclusão de Na+ e não ao acúmulo de prolina na parte aérea da planta. K Na decumbens dias U Observouse Observou se 'Basilisk aéreos 'Marandu Piatã, Piatã , 'Piatã' Xaraés, 'Xaraés' atribuído principalmente planta 'Piatã 'Xaraés

Abstract The objective of this work was to evaluate the effect of salinity on Na+ and K+ distribution and on proline content in Urochloa brizantha and Urochloa decumbens grass cultivars. Plants were grown in nutrient solution and subjected to salt stress for nine days. Shoot and root lengths and proline, total chlorophyll, K+, and Na+ contents were determined. Salt stress reduced the shoot length of cultivar Marandu but not of Xaraés and Basilisk. Total chlorophyll content was not affected by salinity in U. brizantha cultivars, but increased in cultivar Basilisk of U. decumbens. Salt-induced proline accumulation was observed in all cultivars, with a higher increase in Marandu. The K+ content in leaf blades increased in the Marandu and Basilisk cultivars under salinity conditions. 'Basilisk' showed Na+ exclusion in shoot tissues, whereas 'Marandu' and 'Piatã', followed by 'Xaraés', exhibited a higher Na+ in leaf blades. The pattern of ion distribution among cultivars was attributed mainly to differences in the ability to control the ion transport from root to shoot, since the rates of ion uptake were similarly affected by salinity. Tolerance to salt stress in grasses of the Urochloa genus is associated to Na+ exclusion and not to proline accumulation in shoot tissues. Na K days determined U Saltinduced induced conditions 'Basilisk tissues 'Marandu Piatã, Piatã , 'Piatã' Xaraés, 'Xaraés' 'Piatã 'Xaraés

RESUMO Objetivo: Avaliar o impacto de um protocolo de manejo da dor e redução do consumo de opioides no consumo geral de opioides e nos desfechos clínicos. Métodos: Estudo em centro único, quasi-experimental, retrospectivo, de coortes antes e depois. Utilizamos uma série temporal interrompida para analisar as alterações no nível e na tendência de utilização de diferentes analgésicos. Foram usadas comparações bivariadas nas coortes antes e depois, regressão logística e regressão quantílica para estimativas ajustadas. Resultados: Incluímos 988 pacientes no período pré-intervenção e 1.838 no período pós-intervenção. O consumo de fentanil teve ligeiro aumento gradual antes da intervenção (β = 16; IC95% 7 - 25; p = 0,002), porém diminuiu substancialmente em nível com a intervenção (β = - 128; IC95% -195 - -62; p = 0,001) e, a partir de então, caiu progressivamente (β = - 24; IC95% -35 - -13; p < 0,001). Houve tendência crescente de utilização de dipirona. A duração da ventilação mecânica foi significantemente menor (diferença mediana: - 1 dia; IC95% -1 - 0; p < 0,001), especialmente para pacientes mecanicamente ventilados por períodos mais longos (diferença no 50º percentil: -0,78; IC95% -1,51 - -0,05; p = 0,036; diferença no 75º percentil: -2,23; IC95% -3,47 - -0,98; p < 0,001). Conclusão: Um protocolo de manejo da dor conseguiu reduzir o consumo de fentanil na unidade de terapia intensiva. Esta estratégia se associou com menor duração da ventilação mecânica.

ABSTRACT Objective: To evaluate the impact of an opioid-sparing pain management protocol on overall opioid consumption and clinical outcomes. Methods: This was a single-center, quasi-experimental, retrospective, before and after cohort study. We used an interrupted time series to analyze changes in the levels and trends of the utilization of different analgesics. We used bivariate comparisons in the before and after cohorts as well as logistic regression and quantile regression for adjusted estimates. Results: We included 988 patients in the preintervention period and 1,838 in the postintervention period. Fentanyl consumption was slightly increasing before the intervention (β = 16; 95%CI 7 - 25; p = 0.002) but substantially decreased in level with the intervention (β = - 128; 95%CI -195 - -62; p = 0.001) and then progressively decreased (β = - 24; 95%CI -35 - -13; p < 0.001). There was an increasing trend in the utilization of dipyrone. The mechanical ventilation duration was significantly lower (median difference: - 1 day; 95%CI -1 - 0; p < 0.001), especially for patients who were mechanically ventilated for a longer time (50th percentile difference: -0.78; 95%CI -1.51 - -0.05; p = 0.036; 75th percentile difference: -2.23; 95%CI -3.47 - -0.98; p < 0.001). Conclusion: A pain management protocol could reduce the intensive care unit consumption of fentanyl. This strategy was associated with a shorter mechanical ventilation duration.

RESUMO Meralgia parestésica é caracterizada por dor, parestesia ou queimação e diminuição da sensibilidade tátil e dolorosa na face anterolateral da coxa. Isto ocorre por uma neuropatia do nervo cutâneo femoral lateral (NCFL). O tratamento conservador é frequentemente bem-sucedido, aliviando os sintomas na maioria dos pacientes. Descrevemos o caso de uma paciente de 44 anos de idade que apresentou os sintomas descritos após uso pós-operatório de malha modeladora por cirurgia estética. dor coxa NCFL. NCFL . (NCFL) bemsucedido, bemsucedido bem sucedido, sucedido bem-sucedido pacientes 4 pósoperatório pós operatório estética (NCFL

ABSTRACT Meralgia paresthetica is characterized by pain, paresthesia or burning sensation, and reduction of tactile and pain sensitivity in the anterolateral surface of the thigh. This disability is caused by a neuropathy of the lateral femoral cutaneous nerve (LFCN). Conservative treatment is often successful at relieving the symptoms in the majority of patients. We describe the case of a 44-year-old patient who presented with these symptoms caused by postoperative use of a surgical girdle after aesthetic surgery. sensation thigh LFCN. LFCN . (LFCN) patients 44yearold yearold 44 year old surgery (LFCN 4

In 1992, a new type of influenza virus appeared in Southeast Asia. This new strain has caused to date, more than 120 cases and over 60 deaths in Cambodia, Vietnam, Indonesia and Thailand. This situation is seen by the experts as the possible genesis of a new influenza pandemic with the corresponding negative effects on the health of the population, international commerce and world economy. In order to face the coming challenge, the World Health Organization (WHO) has asked member countries to develop national preparedness and response plans for an influenza pandemic. Within the framework of the National Committee for Health Security, Mexico has developed a National Preparedness and Response Plan for an Influenza Pandemic with the aim of protecting the health of the population with timely and effective measures. The Plan is based on a risk scale and five lines of action: Coordination, Epidemiological Surveillance, Medical Care, Risk Communication and Strategic Stockpile. It is currently impossible to predict when the next pandemic will start or what will be its impact. Nevertheless, it is fundamental that national and regional health authorities establish measures for protecting the health of the population in case this emergency occurs.

En 1992 apareció en el sureste asiático un nuevo tipo de virus de la influenza, el cual ha ocasionado hasta la fecha más de 120 casos y un poco más de 60 defunciones en humanos en Camboya, Vietnam, Indonesia y Tailandia. Esta situación es considerada por los expertos como la probable génesis de una nueva pandemia de influenza, lo que podría traer graves consecuencias para la salud de la población, así como para la economía y el comercio mundial. Por lo anterior, la Organización Mundial de la Salud (OMS) ha instado a los países miembros a desarrollar planes de preparación y respuesta para hacer frente a esta eventualidad. En el marco del Comité Nacional para la Seguridad en Salud, México ha diseñado el Plan Nacional de Preparación y Respuesta ante una Pandemia de Influenza con objeto de proteger a la población mediante acciones efectivas y oportunas. El Plan utiliza una escala de riesgo y define cinco líneas de acción: Coordinación, Vigilancia Epidemiológica, Atención Médica, Difusión y Movilización Social, y Reserva Estratégica. Si bien es imposible predecir cuándo se presentará la próxima pandemia y su impacto, es fundamental que las autoridades de salud nacionales, estatales y locales establezcan los mecanismos para poner en marcha los componentes del Plan en forma oportuna y garantizar con ello la salud de la población en caso de influenza pandémica.

In 1992, a new type of influenza virus appeared in Southeast Asia. This new strain has caused to date, more than 120 cases and over 60 deaths in Cambodia, Vietnam, Indonesia and Thailand. This situation is seen by the experts as the possible genesis of a new influenza pandemic with the corresponding negative effects on the health of the population, international commerce and world economy. In order to face the coming challenge, the World Health Organization (WHO) has asked member countries to develop national preparedness and response plans for an influenza pandemic. Within the framework of the National Committee for Health Security, Mexico has developed a National Preparedness and Response Plan for an Influenza Pandemic with the aim of protecting the health of the population with timely and effective measures. The Plan is based on a risk scale and five lines of action: Coordination, Epidemiological Surveillance, Medical Care, Risk Communication and Strategic Stockpile. It is currently impossible to predict when the next pandemic will start or what will be its impact. Nevertheless, it is fundamental that national and regional health authorities establish measures for protecting the health of the population in case this emergency occurs.

En 1992 apareció en el sureste asiático un nuevo tipo de virus de la influenza, el cual ha ocasionado hasta la fecha más de 120 casos y un poco más de 60 defunciones en humanos en Camboya, Vietnam, Indonesia y Tailandia. Esta situación es considerada por los expertos como la probable génesis de una nueva pandemia de influenza, lo que podría traer graves consecuencias para la salud de la población, así como para la economía y el comercio mundial. Por lo anterior, la Organización Mundial de la Salud (OMS) ha instado a los países miembros a desarrollar planes de preparación y respuesta para hacer frente a esta eventualidad. En el marco del Comité Nacional para la Seguridad en Salud, México ha diseñado el Plan Nacional de Preparación y Respuesta ante una Pandemia de Influenza con objeto de proteger a la población mediante acciones efectivas y oportunas. El Plan utiliza una escala de riesgo y define cinco líneas de acción: Coordinación, Vigilancia Epidemiológica, Atención Médica, Difusión y Movilización Social, y Reserva Estratégica. Si bien es imposible predecir cuándo se presentará la próxima pandemia y su impacto, es fundamental que las autoridades de salud nacionales, estatales y locales establezcan los mecanismos para poner en marcha los componentes del Plan en forma oportuna y garantizar con ello la salud de la población en caso de influenza pandémica.

In early February 2003, the World Health Organization (WHO) began receiving reports of patients with a syndrome characterized by an atypical pneumonia with rapid progression to respiratory failure without an identified cause despite extensive diagnostic workups. Most of these reports pointed out that the outbreak started in Southern China, specifically in the Guandong Province. The initial outbreak in South East Asia has already spread to other Regions in Asia, Europe, North and South America, and South Africa. Many of these cases can be linked through chains of transmission to an index case from the Guandong Province who visited Hong Kong. Although the exact mode of transmission has not been clearly established, the etiology of this syndrome has already been identified. A novel Coronavirus has been identified by electron microscopy and molecular assays in multiple laboratories from respiratory specimens throughout the world. The syndrome has been defined as SARS (Severe Acute Respiratory Syndrome) by WHO, and is characterized by an incubation period between 1 and 10 days (average 5 days) and by a febrile phase that usually lasts approximately 3 days. During the respiratory phase that begins around day 3, patients start developing a dry cough, shortness of breath and hypoxemia. Mechanical ventilatory support is required in about 10 to 40% of cases and the case-fatality rate ranges between 3 and 16%. The laboratory findings in SARS cases include leukopenia, thrombocytopenia, and a rise in transaminases and lactic dehydrogenase levels. Treatment of SARS includes supportive measures and the empiric use of ribavirin. Respiratory isolation, use of respiratory masks, and compulsory hand hygiene constitute the principal preventive measures. The confirmation of a case can be performed at reference laboratories by serologic and molecular assays. From the onset of this epidemic Mexico established a surveillance system as well as clinical guidelines and recommendations for the identification, prevention of secondary spread, and medical management of suspicious and probable cases by health care personnel.

A principios de febrero de 2003 la Organización Mundial de la Salud comenzó a recibir reportes de pacientes con un síndrome caracterizado por neumonía atípica, con rápida progresión hacia insuficiencia respiratoria sin una causa identificada. Los casos aparentemente se iniciaron en el sur de China y se han diseminado a otras regiones en Asia, Europa, Sudáfrica, Norte América y Sur América. La causa de este síndrome es una nueva variedad de Coronavirus, aislado en secreciones respiratorias y en otras. El síndrome ha sido definido en inglés como SARS (Severe acute respiratory syndrome) por la Organización Mundial de la Salud y se caracteriza por un periodo de incubación de 1 a 10 días (promedio de cinco días), una fase febril prodrómica que aparece entre los días 1 a 3. Posteriormente, aparecen síntomas respiratorios como tos, disnea, y signos como hipoxemia, que en 10 a 40% de los casos requieren de ventilación mecánica. La tasa de letalidad ha variado de 3% hasta 16%. Los hallazgos de laboratorio incluyen trombocitopenia, leucopenia, elevación de creatinin-fosfokinasa, y, en ocasiones, de transaminasas hepáticas y deshidrogenasa láctica. El tratamiento incluye medidas de apoyo; la utilización empírica del antiviral ribavirina es controvertida, debido a que hasta el momento no existe un tratamiento específico. Se recomienda el aislamiento respiratorio de los pacientes, la utilización de máscaras protectoras y el lavado estricto de manos como principales medidas de prevención. Desde el inicio de esta epidemia México estableció un sistema de vigilancia, así como recomendaciones al personal de salud para la identificación, prevención de casos secundarios y manejo clínico de casos sospechosos.

In early February 2003, the World Health Organization (WHO) began receiving reports of patients with a syndrome characterized by an atypical pneumonia with rapid progression to respiratory failure without an identified cause despite extensive diagnostic workups. Most of these reports pointed out that the outbreak started in Southern China, specifically in the Guandong Province. The initial outbreak in South East Asia has already spread to other Regions in Asia, Europe, North and South America, and South Africa. Many of these cases can be linked through chains of transmission to an index case from the Guandong Province who visited Hong Kong. Although the exact mode of transmission has not been clearly established, the etiology of this syndrome has already been identified. A novel Coronavirus has been identified by electron microscopy and molecular assays in multiple laboratories from respiratory specimens throughout the world. The syndrome has been defined as SARS (Severe Acute Respiratory Syndrome) by WHO, and is characterized by an incubation period between 1 and 10 days (average 5 days) and by a febrile phase that usually lasts approximately 3 days. During the respiratory phase that begins around day 3, patients start developing a dry cough, shortness of breath and hypoxemia. Mechanical ventilatory support is required in about 10 to 40% of cases and the case-fatality rate ranges between 3 and 16%. The laboratory findings in SARS cases include leukopenia, thrombocytopenia, and a rise in transaminases and lactic dehydrogenase levels. Treatment of SARS includes supportive measures and the empiric use of ribavirin. Respiratory isolation, use of respiratory masks, and compulsory hand hygiene constitute the principal preventive measures. The confirmation of a case can be performed at reference laboratories by serologic and molecular assays. From the onset of this epidemic Mexico established a surveillance system as well as clinical guidelines and recommendations for the identification, prevention of secondary spread, and medical management of suspicious and probable cases by health care personnel.

A principios de febrero de 2003 la Organización Mundial de la Salud comenzó a recibir reportes de pacientes con un síndrome caracterizado por neumonía atípica, con rápida progresión hacia insuficiencia respiratoria sin una causa identificada. Los casos aparentemente se iniciaron en el sur de China y se han diseminado a otras regiones en Asia, Europa, Sudáfrica, Norte América y Sur América. La causa de este síndrome es una nueva variedad de Coronavirus, aislado en secreciones respiratorias y en otras. El síndrome ha sido definido en inglés como SARS (Severe acute respiratory syndrome) por la Organización Mundial de la Salud y se caracteriza por un periodo de incubación de 1 a 10 días (promedio de cinco días), una fase febril prodrómica que aparece entre los días 1 a 3. Posteriormente, aparecen síntomas respiratorios como tos, disnea, y signos como hipoxemia, que en 10 a 40% de los casos requieren de ventilación mecánica. La tasa de letalidad ha variado de 3% hasta 16%. Los hallazgos de laboratorio incluyen trombocitopenia, leucopenia, elevación de creatinin-fosfokinasa, y, en ocasiones, de transaminasas hepáticas y deshidrogenasa láctica. El tratamiento incluye medidas de apoyo; la utilización empírica del antiviral ribavirina es controvertida, debido a que hasta el momento no existe un tratamiento específico. Se recomienda el aislamiento respiratorio de los pacientes, la utilización de máscaras protectoras y el lavado estricto de manos como principales medidas de prevención. Desde el inicio de esta epidemia México estableció un sistema de vigilancia, así como recomendaciones al personal de salud para la identificación, prevención de casos secundarios y manejo clínico de casos sospechosos.

Objective. To assess the genotoxic activity of N-nitroso diethylamine (NDEA), maleic hydrazide (MH), and ethyl methane sulfonate (EMS) using two systems: the comet assay on nuclei from Tradescantia, and the pink mutation test on Tradescantia staminal hairs (clone 4430). Material and Methods. Tradescantia cups was obtained from Laboratorio de Citogenética y Mutagénesis del Centro de Ciencias de la Atmósfera de la Universidad Nacional Autónoma de México and treated with: N-nitroso diethylamine (NDEA) at 1, 5, 10 mM, maleic hidrazide (MH) at 1, 5, 10 mM and ethyl methane sulfonate (EMS) at 15, 30 and 45 mM; and used in both pink mutation assay and comet assay using cellular nuclei from Tradescantia staminal hairs. The observation of staminal hair was realized along eight days (6-14) after treatment), flowers produced day 14 after treatment were utilized done according to Underbrink. In previous reports on plants, were comet assay was used, breaking cellular wall and separating by centrifugation gradient are necessary. Here, nuclei from staminal hairs were obtained by squashing the cells (is not necessary to utilize to break special procedure cellular wall), collected using a nylon mesh of 80Mm and next the comet assay was applied. Student's T test was the statistical test used for analyzing the comet assay data. Results. Both assays showed a great sensitivity to the studied mutagens. A relationship between the dose-pink event and the dose-tail length was evident. Even though the Tradescantia mutation assay is a sensitive test with MH and EMS, low doses of NDEA were not able to induce a significant increase in the pink event frequencies; however, the comet assay was able to detect the mutagenic effect of NDEA at the same dose. Thus, it is clear that the comet assay is highly sensitive to the lowest dose of chemical mutagens. Conclusions. The comet assay on nuclei from Tradescantia staminal hairs is a useful tool to monitor genotoxic agents; it is simple, highly sensitive, and faster than the pink mutation test. The English version of this paper is available too at: <A HREF="http://www.insp.mx/salud/index.html">http://www.insp.mx/salud/index.html </A>

Objetivo. Evaluar la genotoxicidad de N-nitroso dietilamina (NDEA), hidrazida málica (MH) y etil metano sulfonato (EMS), en núcleos de Tradescantia (clona 4430) por medio de la prueba del cometa y de la prueba de mutación rosa, en los pelos estaminales de la misma planta. Material y métodos. Las plantas de Tradescantia (clon 4430) fueron obtenidas del Laboratorio de Citogenética y Mutagénesis del Centro de ciencias de la Atmósfera de la Universidad Nacional Autónoma de México, tratadas con NDEA a 1, 5, 10 mM, MH a 1, 5, 10 mM y EMS a 15, 30 y 45 mM, y utilizadas en la prueba de mutación rosa y en la del cometa, en núcleos celulares de los pelos estaminales. En la primera, la lectura de los pelos estaminales se realizó de acuerdo con el método de Underbrink. En otros estudios, que han aplicado la prueba del cometa en plantas, existe la necesidad de romper la pared celular y separar los núcleos por gradiente de centrifugación; en este caso, los núcleos de las células de los pelos estaminales fueron extraídos por aplastamiento sin aplicar un procedimiento especial para romper la pared, colectados por filtración en una malla de nylon y sometidos a la prueba del cometa. La prueba t de Student se usó para analizar los datos obtenidos. Resultados. Ambas pruebas presentaron una gran sensibilidad a los mutágenos estudiados y hubo una relación evidente dosis-eventos rosa / longitud de la cauda. Aunque la prueba de mutación rosa en Tradescantia fue muy sensible a MH y EMS, no se detectaron dosis bajas de NDEA; en cambio, la prueba del cometa en la misma planta permite detectar fácilmente la actividad de todos los agentes estudiados. Conclusión. La prueba del cometa en los núcleos de las células de los pelos estaminales de Tradescantia es una útil herramienta para los estudios de monitoreo. Además, es simple, sensible y más rápida que la prueba de mutación rosa en la misma planta. El texto completo en inglés de este artículo también está disponible en: <A HREF="http://www.insp.mx/salud/index.html">http://www.insp.mx/salud/index.html </A>

Objective. To assess the genotoxic activity of N-nitroso diethylamine (NDEA), maleic hydrazide (MH), and ethyl methane sulfonate (EMS) using two systems: the comet assay on nuclei from Tradescantia, and the pink mutation test on Tradescantia staminal hairs (clone 4430). Material and Methods. Tradescantia cups was obtained from Laboratorio de Citogenética y Mutagénesis del Centro de Ciencias de la Atmósfera de la Universidad Nacional Autónoma de México and treated with: N-nitroso diethylamine (NDEA) at 1, 5, 10 mM, maleic hidrazide (MH) at 1, 5, 10 mM and ethyl methane sulfonate (EMS) at 15, 30 and 45 mM; and used in both pink mutation assay and comet assay using cellular nuclei from Tradescantia staminal hairs. The observation of staminal hair was realized along eight days (6-14) after treatment), flowers produced day 14 after treatment were utilized done according to Underbrink. In previous reports on plants, were comet assay was used, breaking cellular wall and separating by centrifugation gradient are necessary. Here, nuclei from staminal hairs were obtained by squashing the cells (is not necessary to utilize to break special procedure cellular wall), collected using a nylon mesh of 80Mm and next the comet assay was applied. Student's T test was the statistical test used for analyzing the comet assay data. Results. Both assays showed a great sensitivity to the studied mutagens. A relationship between the dose-pink event and the dose-tail length was evident. Even though the Tradescantia mutation assay is a sensitive test with MH and EMS, low doses of NDEA were not able to induce a significant increase in the pink event frequencies; however, the comet assay was able to detect the mutagenic effect of NDEA at the same dose. Thus, it is clear that the comet assay is highly sensitive to the lowest dose of chemical mutagens. Conclusions. The comet assay on nuclei from Tradescantia staminal hairs is a useful tool to monitor genotoxic agents; it is simple, highly sensitive, and faster than the pink mutation test. The English version of this paper is available too at: <A HREF="http://www.insp.mx/salud/index.html">http://www.insp.mx/salud/index.html </A>

Objetivo. Evaluar la genotoxicidad de N-nitroso dietilamina (NDEA), hidrazida málica (MH) y etil metano sulfonato (EMS), en núcleos de Tradescantia (clona 4430) por medio de la prueba del cometa y de la prueba de mutación rosa, en los pelos estaminales de la misma planta. Material y métodos. Las plantas de Tradescantia (clon 4430) fueron obtenidas del Laboratorio de Citogenética y Mutagénesis del Centro de ciencias de la Atmósfera de la Universidad Nacional Autónoma de México, tratadas con NDEA a 1, 5, 10 mM, MH a 1, 5, 10 mM y EMS a 15, 30 y 45 mM, y utilizadas en la prueba de mutación rosa y en la del cometa, en núcleos celulares de los pelos estaminales. En la primera, la lectura de los pelos estaminales se realizó de acuerdo con el método de Underbrink. En otros estudios, que han aplicado la prueba del cometa en plantas, existe la necesidad de romper la pared celular y separar los núcleos por gradiente de centrifugación; en este caso, los núcleos de las células de los pelos estaminales fueron extraídos por aplastamiento sin aplicar un procedimiento especial para romper la pared, colectados por filtración en una malla de nylon y sometidos a la prueba del cometa. La prueba t de Student se usó para analizar los datos obtenidos. Resultados. Ambas pruebas presentaron una gran sensibilidad a los mutágenos estudiados y hubo una relación evidente dosis-eventos rosa / longitud de la cauda. Aunque la prueba de mutación rosa en Tradescantia fue muy sensible a MH y EMS, no se detectaron dosis bajas de NDEA; en cambio, la prueba del cometa en la misma planta permite detectar fácilmente la actividad de todos los agentes estudiados. Conclusión. La prueba del cometa en los núcleos de las células de los pelos estaminales de Tradescantia es una útil herramienta para los estudios de monitoreo. Además, es simple, sensible y más rápida que la prueba de mutación rosa en la misma planta. El texto completo en inglés de este artículo también está disponible en: <A HREF="http://www.insp.mx/salud/index.html">http://www.insp.mx/salud/index.html </A>