Evaluación de los efectos genotóxicos del herbicida 2,4-D en Piaractus mesopotamicus a través del test de micronúcleos

The herbicide 2,4-D is currently one of the most used agrochemicals in agriculture. The fish are target of contamination, these when being in contact with toxics develop later alterations that can be studied, reason why they are used as models in the evaluation of aquatic ecosystems. There is scarce information about the effects of these pesticides in fish. Because of this, the objective of this work was to evaluate the possible impact of a contamination with 2,4-D, in sub-lethal concentrations in Piaractus mesopotamicus, through the frequency of micronuclei (MN) and alterations in the shape of the nuclei (NMA) in peripheral blood erythrocytes in chronic conditions (70 days). Two trials were conducted, one with the herbicide 2,4-D pure (P) and another with a commercial formulation (2,4-D bitter amine) (FC). Each experience was composed of five aquariums with two specimens in each, where different concentrations of the pesticide were administered (1 ppm, 1.8 ppm, 3.2 ppm, 5.6 ppm and 10 ppm), and in another with well water (control). A total of 4000 cells per individual were analyzed. Through the test MN and NMA the presence of diverse nuclear alterations was evidenced. The mentioned test for P and dilutions 1 ppm, 1.8 ppm, 3.2 ppm, 5.6 ppm of FC did not show significant differences with the control, while the concentration of 10 ppm of FC differed statistically from its control, this could be due to additional components in FC.Los herbicidas están siendo abundantemente utilizados haciendo que los mismos no solo lleguen al organismo específico sino también contaminen el medio ambiente donde son empleados. El herbicida 2,4-D es en la actualidad uno de los agroquímicos más utilizado en la agricultura. Los peces son blanco de la contaminación, éstos al estar en contacto con tóxicos desarrollan posteriormente alteraciones que pueden ser estudiadas, por lo cual son utilizados como modelos en la evaluacion de ecosistemas acuáticos. Existe escasa información acerca de los efectos de estos pesticidas en peces, siendo el actual trabajo el primero en evaluar efectos crónicos. El objetivo de la presente investigación fue evaluar el posible impacto de una contaminación con 2,4-D en concentraciones subletales en Piaractus mesopotamicus, a través de la frecuencia de micronúcleos (MN) y de las alteraciones en la forma de los núcleos (NMA) en eritrocitos de sangre periférica en condiciones crónicas (70 días). Se realizaron dos ensayos, uno con el herbicida 2,4-D puro (P) y otro con una formulación comercial (2,4-D amina Sumargo) (FC). Cada experiencia estuvo compuesta por cinco acuarios con dos ejemplares en cada uno, donde se administraron difererentes concentraciones del plaguicida (1 ppm, 1,8 ppm, 3,2 ppm, 5,6 ppm y 10 ppm), y en otra con agua de pozo (control). Se analizó un total de 4000 células por individuo. A través del test MN y NMA se evidenció la presencia de diversas alteraciones nucleares. El mencionado test para P y las diluciones 1 ppm, 1,8 ppm, 3,2 ppm, 5,6 ppm de FC no mostraron diferencias significativas con el control, mientras que la concentración de 10 ppm de FC se diferenció estadísticamente de su control. El presente trabajo aporta luz de los potenciales efectos nocivos del 2,4-D en el medio ambiente y posibilita nuevos estudios prospectivos y retrospectivos

Anormalidades morfológicas nucleares en hematíes del pez Prochilodus linneatus expuesto al clorpirifos

In recent years, the monitoring of xenobiotics (chemicals such as pesticides) in the environment has been very important, as the persistence of the biological activity of many of these compounds has been recognized. Chlorpyrifos is an organophosphorus insecticide of broad spectrum, used in agricultural and domestic activities. This pesticide as well as other chemicals may accidentally reach the aquatic ecosystem and the ictic fauna. Fish ingesting contaminated substances subsequently develop alterations due to bioaccumulation, becoming effective indicators of environmental pollution. The purpose of this study was to evaluate the genotoxicity of chlorpyrifos in P. linneatus (Pisces, Prochilodontidae) through the frequency of micronuclei (MN) and nuclear morphology alterations (AMN) in peripheral blood erythrocytes. After acclimatization the fish were divided into two control (C) and treated groups (T1 = 10 μg/l, T2 = 30 μg/l and T3 = 90 μg/l). Three replicates per group (C, T) were performed with a total of 3 animals per fishbowl. The animals remained in the aquariums for a period of 7 days. After this time they were sacrificed with an overdose of anaesthetic to extract blood from the caudal vein. Smears were stained with Giemsa. In the samples analyzed, the number of MN and AMN was determined after observation of 2000 cells per animal. Cells with intact cytoplasmic membrane were considered for the study. The analysis of blood smears in both groups revealed the presence of micronuclei and the following nuclear morphology alterations; notches, lobulated, evaginations, eigth shaped, segmentations and vacuolization nuclei. Individuals T3 showed significant variations in the frequency of MN and AMN with respect to the controls (p<0.05), but not the T1 and T2 specimens. We conclude that chlorpyrifos at a dose of 90 μg/l could be harmful to the environment.Recientemente adquirió importancia el monitoreo de xenobióticos (como pesticidas) en el medio ambiente, debido a la persistencia de la actividad biológica de muchos de ellos. Clorpirifos es un insecticida organofosforado empleado a nivel agrícola y doméstico. Este plaguicida puede alcanzar accidentalmente el ecosistema acuático y la fauna íctica. Al ingerir sustancias contaminadas, los peces desarrollan alteraciones debidas a la bioacumulación, constituyéndose en eficaces indicadores de polución ambiental. El propósito del estudio fue evaluar la genotoxicidad del clorpirifos en P. linneatus (Pisces, Prochilodontidae) a través de la frecuencia de micronúcleos (MN) y de alteraciones de la morfología nuclear (AMN) en eritrocitos de sangre periférica. Los ensayos se realizaron con clorpirifos en su forma pura (Sigma Aldrich). Los peces se dividieron en grupos control (C) y tratados (T1 = 10 μg/l; T2 = 30 μg/l y T3 = 90 μg/l). Se realizaron tres replicas por grupo, con un total de 3 animales por pecera, los cuales permanecieron allí durante 7 días, tras lo cual fueron sacrificados con sobredosis de anestésico. Se extrajo sangre de la vena caudal, realizándose frotis que se colorearon con Giemsa, determinándose el número de MN y AMN luego de la observación de 2000 células por animal. Para el estudio se consideraron las células con sus membranas citoplasmáticas intactas. En ambos grupos, los frotis sanguíneos revelaron la presencia de micronúcleos, así como algunas de las siguientes alteraciones de la morfología nuclear: muesca, lobulación, evaginación, forma de ocho, segmentación y vacuolización nuclear. Los individuos del grupo T3 mostraron variaciones significativas en la frecuencia de MN y AMN respecto a los controles (p<0,05), no así los ejemplares de los tratamientos T1 y T2. Por lo expuesto, surge que el clorpirifos a la dosis de 90 μg/l podría ser nocivo para el medio ambiente

Long-Term Changes in Physical Activity Following a One-Year Home-Based Physical Activity Counseling Program in Older Adults with Multiple Morbidities

This study assessed the sustained effect of a physical activity (PA) counseling intervention on PA one year after intervention, predictors of sustained PA participation, and three classes of post-intervention PA trajectories (improvers, maintainers, and decliners) in 238 older Veterans. Declines in minutes of PA from 12 to 24 months were observed for both the treatment and control arms of the study. PA at 12 months was the strongest predictor of post-intervention changes in PA. To our surprise, those who took up the intervention and increased PA levels the most, had significant declines in post-intervention PA. Analysis of the three post-intervention PA trajectories demonstrated that the maintenance group actually reflected a group of nonresponders to the intervention who had more comorbidities, lower self-efficacy, and worse physical function than the improvers or decliners. Results suggest that behavioral counseling/support must be ongoing to promote maintenance. Strategies to promote PA appropriately to subgroups of individuals are needed

Gadolinium and nephrogenic systemic fibrosis: time to tighten practice

Nephrogenic systemic fibrosis (NSF) is a relatively new entity, first described in 1997. Few cases have been reported, but the disease has high morbidity and mortality. To date it has been seen exclusively in patients with renal dysfunction. There is an emerging link with intravenous injection of gadolinium contrast agents, which has been suggested as a main triggering factor, with a lag time of days to weeks. Risk factors include the severity of renal impairment, major surgery, vascular events and other proinflammatory conditions. There is no reason to believe that children have an altered risk compared to the adult population. It is important that the paediatric radiologist acknowledges emerging information on NSF but at the same time considers the risk:benefit ratio prior to embarking on alternative investigations, as children with chronic kidney disease require high-quality diagnostic imaging

Elevated hemostasis markers after pneumonia increases one-year risk of all-cause and cardiovascular deaths

Background: Acceleration of chronic diseases, particularly cardiovascular disease, may increase long-term mortality after community-acquired pneumonia (CAP), but underlying mechanisms are unknown. Persistence of the prothrombotic state that occurs during an acute infection may increase risk of subsequent atherothrombosis in patients with pre-existing cardiovascular disease and increase subsequent risk of death. We hypothesized that circulating hemostasis markers activated during CAP persist at hospital discharge, when patients appear to have recovered clinically, and are associated with higher mortality, particularly due to cardiovascular causes. Methods: In a cohort of survivors of CAP hospitalization from 28 US sites, we measured D-Dimer, thrombin-antithrombin complexes [TAT], Factor IX, antithrombin, and plasminogen activator inhibitor-1 at hospital discharge, and determined 1-year all-cause and cardiovascular mortality. Results: Of 893 subjects, most did not have severe pneumonia (70.6% never developed severe sepsis) and only 13.4% required intensive care unit admission. At discharge, 88.4% of subjects had normal vital signs and appeared to have clinically recovered. D-dimer and TAT levels were elevated at discharge in 78.8% and 30.1% of all subjects, and in 51.3% and 25.3% of those without severe sepsis. Higher D-dimer and TAT levels were associated with higher risk of all-cause mortality (range of hazard ratios were 1.66-1.17, p = 0.0001 and 1.46-1.04, p = 0.001 after adjusting for demographics and comorbid illnesses) and cardiovascular mortality (p = 0.009 and 0.003 in competing risk analyses). Conclusions: Elevations of TAT and D-dimer levels are common at hospital discharge in patients who appeared to have recovered clinically from pneumonia and are associated with higher risk of subsequent deaths, particularly due to cardiovascular disease. © 2011 Yende et al

Rendimiento neto, humedad, cenizas y minerales en hígado y músculos de pollos sometidos a estrés en temporadas estival e invernal

Para evaluar los efectos del estrés sobre la calidad de la canal de polloscriados en jaulas, se compararon lotes control (C) y experimental (E) durante las temporadasestival e invernal. Las aves eran machos provenientes del cruzamiento Rhode Island x PlymouthRock Barrada. El lote E (n = 4) fue sometido 2 veces por semana a maniobras inductorasde estrés, consistentes en sujeción, hacinamiento e inversión corporal durante todo el ciclode crianza, mientras que el lote C (n = 4) continuó su desarrollo en condiciones normales. Lasaves fueron sacrificadas a los 55 días. Se evaluaron los pesos corporales, así como el peso decanal, hígado y músculos de pata y pechuga. Se determinó el rendimiento, humedad, cenizas,macrominerales (Ca, Mg, K) y microminerales (Cu, Fe, Zn) en hígado y músculos. El análisisde la variancia no reveló diferencias significativas atribuibles al estrés, pero en la mayoría delas variables productivas estudiadas (peso final, rendimiento de pata, porcentaje de humedaden pechuga y proporciones de hígado y desperdicios con respecto al peso corporal), se registrarondiferencias significativas entre temporadas (p < 0,05). Cenizas y minerales tambiénfueron significativamente distintos entre temporadas. En período estival se hallaron valoresmás altos de cenizas en hígado y pata, Ca en hígado, Mg en pechuga y pata, Zn en hígado ypechuga y K en hígado, pechuga y pata. Se concluye que las condiciones ambientales fueroncapaces de provocar mayores modificaciones que las atribuidas al estrés

Patterns and Predictors of Stress Testing Modality after Percutaneous Coronary Stenting: Retrospective Analysis using Data from the NCDR®

We evaluated temporal trends and geographic variation in choice of stress testing modality post-PCI, as well as associations between modality and procedure use after testing

Impact of choice of imaging modality accompanying outpatient exercise stress testing on outcomes and resource use after revascularization for acute coronary syndromes

Exercise stress testing is commonly obtained after percutaneous coronary intervention (PCI) performed for acute coronary syndromes (ACS). We compared the relationships between exercise echocardiography and nuclear testing after ACS-related PCI on outcomes and resource use